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Professore Ordinario
Dipartimento di Scienze e Metodi dell'Ingegneria

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2022 - Circularity Performances of the Production of a Cement Mortar Reinforced with Recycled Synthetic Fibers [Capitolo/Saggio]
Marinelli, Simona; Butturi, Maria Angela; Rimini, Bianca; Gamberini, Rita

Forced by environmental implications and by legislation requirements, the cement sector is moving towards more circular economy practices, with the primary aim to enhance the sector sustainability. This commitment translates into product technology innovation, but also into innovative development perspectives for the industries involved in the supply chain. Moreover, dealing with recycled materials can modify the interaction among stakeholders from a conventional supply chain to an industrial symbiosis approach, where companies mutually exchange products and by-products into circular interactions. The purpose of this article is to investigate the circularity performances deriving from the production of a cement mortar reinforced with recycled synthetic fibers coming from artificial turf carpets. From the collection of artificial turf carpets at the end-of-life stage it is possible to recover several materials: plastic fibers used in the cement mortar, and in addition, silica sand, rubber, and bituminous membrane. The production of the innovative reinforced cement mortar leads to the connection between industries belonging to different sectors and consequently to uneven economic and environmental implications. Starting from the available literature, this study aims at evaluating the circularity potential of the unusual interactions among companies to support the development of an effective strategy, reducing environmental and economic pressures.

2022 - How the type of customer can influence the product attributes: Application of house of quality with multi-user information to improve the functions of a waste collection and treatment service management software [Relazione in Atti di Convegno]
Coruzzolo, A. M.; Marinello, S.; Lolli, F.; Gamberini, R.

2021 - An open innovation B2B web platform design: Application of the QFD approach for the definition of its primary functions [Articolo su rivista]
Marinello, S.; Lolli, F.; Gamberini, R.

Global markets and the concept of innovation require modern companies to quickly adapt to two very relevant paradigms: digital innovation and open innovation. Therefore, the use of digital technologies and the development of open collaboration networks have radically changed the nature of the organisation of innovation and of the managerial approach and strategic choices. The objective of this paper is to describe the approach adopted to define the main functionalities of a digital Business to Business (B2B) platform for the development of new commercial collaborations between Small and Medium-sized Enterprises (SMEs). The approach of Quality Function Deployment and its House of Quality tool have been applied to support the combination of customer and technical needs. The prioritisation of the technical characteristics of the platform has identified in the ‘system for managing orders’ and ‘systems to speed up processes’ the main functions to be developed with greater attention within the platform.

2021 - Circular design options for wearables integrated sportswear to be employed in adverse outdoor conditions [Relazione in Atti di Convegno]
Butturi, M. A.; Barbi, S.; Marinelli, S.; Montorsi, M.; Gamberini, R.

The fashion industry is increasingly committed in improving the sustainability and circularity of its products in a perspective strongly oriented towards technological innovation. To meet these goals, several strategies are used, mainly focusing on product design and production processes. The study of materials suitable for reuse and recycle, the “design for disassembly” of garments, the setup of reverse supply chain to recover the products, and the raising of consumers’ awareness and involvement are some of the most challenging strategies. In this perspective, smart textiles and wearable technologies put together the issues of both the fashion and electronic industry, through a wide range of possible integration strategies, increasing the complexity of the circular system to be designed. Sportswear represents an ideal context to develop wearable technologies, having a target of customers interested in technological innovations and willing to spend more efforts for increasing their performances and safety. Starting from an in-depth analysis of the available literature on the topic, this study aims at analyzing and discussing the possible design strategies for the development of circular wearable technologies, presenting a brief case study on the integration of wearables into a sport shirt, specially designed to increase cyclists and runners’ safety, including athletes with disability, in adverse environmental conditions. The various options are discussed taking into account the different stakeholders’ view, namely the technology developers, the electronic and fashion manufacturers, the fashion retailers and the end users’ needs and objectives. Lastly, an application framework to support the industrialization of the considered smart apparels is presented, providing useful hints to increase the circularity of both smart garments and wearable devices.

2021 - Coffee capsule impacts and recovery techniques: A literature review [Articolo su rivista]
Marinello, S.; Balugani, E.; Gamberini, R.

The recently developing coffee market has been characterized by profound changes caused by new solutions and technologies for coffee preparation. The polylaminate materials that compose most popular capsules make them a type of waste that is difficult to manage and recycle. This paper analyses the scientific references that deal with studying and improving the management processes of waste coffee capsules, as well as the studies that have analysed their environmental impact. Through a bibliographic review, some encouraging aspects emerged in the recovery of materials that can be adequately recycled (plastics and metals), as well as their possible use for the production of biogas and energy recovery. The need to manually separate the components that make up the capsule still represents one of the main challenges. Many efforts are still needed to favour the environmental sustainability of this waste from a strategic, technological and consumer empowerment point of view.

2021 - Dimensionality reduced robust ordinal regression applied to life cycle assessment [Articolo su rivista]
Balugani, E.; Lolli, F.; Pini, M.; Ferrari, A. M.; Neri, P.; Gamberini, R.; Rimini, B.

Life Cycle Assessment quantifies the multi-dimensional impact of goods and services and can be handled by Multi-Criteria Decision Analysis. In Multi-Criteria Decision Analysis, Robust Ordinal Regression manages all the compatible preference functions at once when assessing a set of alternatives and a group of preferences on reference alternatives. Robust Ordinal Regression is thus a versatile method of reducing the cognitive effort required by decision makers for eliciting their preference structures in Life Cycle Assessment, although it does not directly operate on noisy alternatives and requires Stochastic Multicriteria Acceptability Analysis to deal with such scenarios. We propose integrating a dimensionality reduction technique, Principal Component Analysis, and Robust Ordinal Regression methods, to reduce the problem dimensionality and ensure the actual problem features are considered. A generated dataset, a dataset from literature and a Life Cycle Assessment case study are used to test the effectiveness of the proposed methods.

Coruzzolo, A. M.; Lolli, F.; Gennari, F.; Marinello, S.; Gamberini, R.

An increasing freight demand is putting pressure on the freight transport network, forced to pay high costs to ensure compliance with the conditions and delivery times, as well as to grow towards environmental sustainability. The purpose of this paper is to analyse the main drivers for choosing the type of transport in the planning of distribution logistics through the application of the Multinomial Logit Model (MLN) under the objective of CO2 emission minimisation in order to identify the most sustainable transport solution as a function of distance along the same lines as Hoover’s diagrams. The approach has been applied to a real case study (the logistics department of an Italian manufacturing company) in order to define the mode of transport that minimises the quantity of carbon dioxide emitted and therefore to analyse the effect that this modal shift strategy has on the other selection drivers. The results were encouraging in guiding the application of a modal shift strategy and the change to more sustainable transport modes: 62.5% of the company’s transport shipments should be transferred from road to a different mode, with an overall reduction of 41% of CO2 emissions, without any impact on costs and delivery time.

2021 - Estimating the circularity performance of an emerging industrial symbiosis network: The case of recycled plastic fibers in reinforced concrete [Articolo su rivista]
Marinelli, S.; Butturi, M. A.; Rimini, B.; Gamberini, R.; Sellitto, M. A.

In recent times, the construction industry has been handling circular economy strategies in order to face the most important challenges in the sector, namely the lack of raw materials and the environmental impacts derived from all the processes linked to the entire supply chain. The industrial symbiosis approach represents an effective strategy to improve the circularity of the construction industry. This study analyses the circularity performance of an emerging industrial symbiosis network derived from the production of a cement mortar reinforced with recycled synthetic fibers coming from artificial turf carpets. From the collection of artificial turf carpets at the end-of-life stage it is possible to recover several materials, leading to potential unusual interactions between industries belonging to different sectors. A suitable indicator, retrieved from the literature, the Industrial Symbiosis Indicator (ISI), has been used to estimate the level of industrial symbiosis associated with increasing materials recirculation inside the network. Four scenarios—ranging from perfect linearity to perfect circularity—representing growing circularity were tested. Findings demonstrate that the development of an effective industrial symbiosis network can contribute to improving the circular approach within the construction sector, reducing environmental and economic pressures.

2021 - How changes in human activities during the lockdown impacted air quality parameters: A review [Articolo su rivista]
Marinello, S.; Butturi, M. A.; Gamberini, R.

The health emergency linked to the spread of COVID-19 has led to important reduction in industrial and logistics activities, as well as to a drastic changes in citizens' behaviors and habits. The restrictions on working activities, journeys and relationships imposed by the lockdown have had important consequences, including for environmental quality. This review aims to provide a structured and critical evaluation of the recent scientific bibliography that analyzed and described the impact of lockdown on human activities and on air quality. The results indicate an important effect of the lockdown during the first few months of 2020 on air pollution levels, compared to previous periods. The concentrations of particulate matter, nitrogen dioxide, sulfur dioxide and carbon monoxide have decreased. Tropospheric ozone, on the other hand, has significantly increased. These results are important indicators that can become decision drivers for future policies and strategies in industrial and logistics activities (including the mobility sector) aimed at their environmental sustainability. The scenario imposed by COVID-19 has supported the understanding of the link between the reduction of polluting emissions and the state of air quality and will be able to support strategic choices for the future sustainable growth of the industrial and logistics sector.

2021 - Improvement of the clinical-care pathway of inguinal hernia surgery: a mathematical model for implementing a feasibility study [Relazione in Atti di Convegno]
Marinello, Samuele; Coruzzolo, ANTONIO MARIA; Mazzi, Giovanni; Gamberini, Rita

The best public sector performance has long been a topic at the core of political, social and economic debate. Public management policies and the growing adoption of corporate governance principles support the transition towards models capable of guaranteeing greater control of results in terms of efficiency, effectiveness, and outcome. Healthcare systems are an example of public service. Due to their high management costs, healthcare systems are often under pressure, especially when there is a need to widen access, to improve their efficiency and their care quality and to reduce inequalities. Operations Management (OM) approaches actively support this path. This article describes a retrospective analysis, in which a surgical rescheduling plan of a hospital in northern Italy (consisting of 6 structures distributed throughout wide provincial area serving over 530,000 inhabitants) has been produced, with particular reference to inguinal hernia surgery as health service subject to optimization. The current situation ("as is" scenario) is characterized by a strong concentration of complex and urgent surgical interventions in two hospital facilities of the hospital network, which are further burdened by less complex planned interventions. A linear integer model has been developed, to determine a possible optimized scenario for the redistribution of surgical interventions, trying to leave complex and urgent cases in the two reference structures, but relieving them of the other cases through a better distribution in the other structures of the network. The costs were the driver used for the scheduling, which resulted to be considerably reduced in the new proposed configuration.

2021 - Indicators for sustainable touristic destinations: a critical review [Articolo su rivista]
Marinello, S.; Butturi, M. A.; Gamberini, R.; Martini, U.

Globally, tourism is currently one of the fastest-growing industries, with strong impacts on territories, from an environmental, economic and social point of view. The increase in the number of tourists who flock to destinations requires greater attention to sustainability through tools (indicators) such as strategic destination management support. This paper, through the review of 104 scientific papers, aims to analyze the structure and evolution of the evaluation and monitoring of sustainable tourism through the use of sets of indicators. In particular, the study favors the understanding of the most significant aspects of sustainable tourism that the literature suggests to analyze, evaluating how these vary in relation to the type of destination and the time period of the study. The results contribute to the understanding of the theoretical and operational aspects which, today, are considered representative of the concept of sustainable tourism, improving the sustainable management of territories.

2021 - Multi-criteria decision making approaches applied to waste electrical and electronic equipment (WEEE): A comprehensive literature review [Articolo su rivista]
Marinello, S.; Gamberini, R.

The global demand for electrical and electronic equipment has undergone continuous growth in recent years due to the effect of industrialization and technological development. This indicates substantial quantities of e-waste that need to be managed properly to reduce their environmental impact and to avoid inappropriate forms of disposal. The purpose of this paper is to review the most popular multi-criteria decision-making approaches applied to the management of waste electrical and electronic equipment, analyzing how they are used to contribute to the improvement of management strategies along the entire supply chain. For this purpose, a methodological protocol for the collection, selection, and analysis of the scientific literature was applied, identifying 44 papers on which to conduct this study. The results showed that numerous authors have developed multi-criteria approaches, with particular attention to recycling phase. The analytic hierarchy process is the most widespread multi-criteria approach, often coupled with VIKOR, DELPHI, and TOPSIS methods. The numerous decision making criteria adopted cover different reference dimensions: environmental, economic, social, technical, and legal. Considering environmental aspects also in decision making processes means enhancing the relevance of this dimension, as well as encouraging practices that reduce the impact of toxic substances on the environment and living organisms.

2021 - The Impact of the COVID-19 Emergency on Local Vehicular Traffic and Its Consequences for the Environment: The Case of the City of Reggio Emilia (Italy) [Articolo su rivista]
Marinello, Samuele; Lolli, Francesco; Gamberini, Rita

first_pagesettings Open AccessArticle The Impact of the COVID-19 Emergency on Local Vehicular Traffic and Its Consequences for the Environment: The Case of the City of Reggio Emilia (Italy) by Samuele Marinello 1,*OrcID,Francesco Lolli 1,2 andRita Gamberini 1,2OrcID 1 En&Tech Interdepartmental Center, University of Modena and Reggio Emilia, 42124 Reggio Emilia, Italy 2 Department of Sciences and Methods for Engineering, University of Modena and Reggio Emilia, 42122 Reggio Emilia, Italy * Author to whom correspondence should be addressed. Sustainability 2021, 13(1), 118; Received: 3 December 2020 / Revised: 21 December 2020 / Accepted: 22 December 2020 / Published: 24 December 2020 (This article belongs to the Special Issue 8th World Sustainability Forum—Selected Papers) Download PDF Browse Figures Abstract The COVID-19 health emergency has imposed the need to limit and/or stop non-essential economic and commercial activities and movement of people. The objective of this work is to report an assessment of the change in vehicle flows and in air quality of a specific study area in the north of Italy, comparing the periods February–May 2020 and February–May 2019. Circulating vehicles have been measured at nine characteristic points of the local road network of the city of Reggio Emilia (Italy), while atmospheric pollutant concentrations have been analysed using data extracted from the regional air quality monitoring network. The results highlight a rapid decline in the number of vehicles circulating in 2020 (with values of up to −82%). This has contributed to a reduction in air concentrations of pollutants, in particular for NO2 and CO (over 30% and over 22%, respectively). On the other hand, O3 has increased (by about +13%), but this is expected. Finally, the particulate matter grew (about 30%), with a behaviour similar to the whole regional territory. The empirical findings of this study provide some indications and useful information to assist in understanding the effects of traffic blocking in urban areas on air quality.

2021 - Understanding the Demand Driven Material Requirements Planning Scope of Application: a Critical Literature Review [Relazione in Atti di Convegno]
Butturi, MARIA ANGELA; De Rosa, Giuseppina; Balugani, Elia; Gamberini, Rita

The supply chains complexity generated by the dynamic market demand imposes the improvement of the classical production control systems. A recently introduced method, the Demand Driven Material Requirements Planning (DDMRP), is proposed as an upgrade of the Material Requirements Planning (MRP), widely used in industry, capable of overcoming the nervousness of MRP environment and the bullwhip effect affecting supply chains under uncertainties. The DDMRP approach, however, is still not well established since the conditions for its application are still little investigated. Thus, this study aims at reviewing the existing scientific literature concerning DDMRP method in order to critically analyse its main scope of application as well as its real practical performance. From the reviewed literature three main research lines emerged: DDMRP basic principles, comparison with other methodologies, and case studies. The analysis of both research oriented papers and case studies points out some critical issues that are limiting the diffusion of the DDMRP method, including the additional costs necessary to adapt the in use control and planning software. The main criticality of the method is recognized to be the high subjectivity affecting the positioning of the buffers, and the need for classifying the suitable sectors of application.

2021 - Waste Management and Covid-19: What does the Scientific Literature Suggest? [Relazione in Atti di Convegno]
Marinello, Samuele; Lolli, Francesco; Gamberini, Rita

The studies conducted on the effects of the health emergency due to COVID-19 have shown heavy consequences on human activities (industrial production, economic activities, tourism), but also interesting improvements for the quality of different environmental matrices (water, air, soil). The waste management sector, which represents an essential public utility service, has suffered very negative consequences. In fact, the global change in the behavior and habits of citizens and the variations in industrial, production and economic processes in general have altered the consolidated dynamics that governed the production and treatment of waste, putting them in crisis. This review intends to provide a structured and critical evaluation of the recent scientific literature about the study of the effect of health emergency on the waste management sector. The results reported showed a general common trend towards a significant increase in the production of hazardous medical waste and packaging plastics, while the increasing or decreasing trend in household waste does not appear uniform. Industrial waste and those associated with public areas and events are decreasing. The recovery and recycling sector suffered a sharp slowdown. In the face of various gaps and criticalities highlighted by the analyzed authors, various possible solutions to improve waste management during emergency situations such as that of COVID-19 have been identified and reported in this review work.

2020 - A second life for cigarette butts? A review of recycling solutions [Articolo su rivista]
Marinello, S.; Lolli, F.; Gamberini, R.; Rimini, B.

Trillions of cigarettes are smoked annually making cigarette butts one of the most common types of litter in the world. Due to the materials and toxic substances that they contain, this waste carries a very harmful risk for the environment and for living organisms (including humans). Only a few - barely sustainable - solutions have tried to tackle this waste and alternative solutions to landfilling and incineration are needed. Identifying the best methodological solutions and technologies for recycling this kind of waste in terms of results and applicability to real contexts would reduce the presence of dangerous materials in the environment and ecosystems and would promote the recovery of materials in line with the circular economy and sustainable development. The objective of this review was to collect and analyze the alternative solutions available in the literature for the recovery and recycling of the materials in cigarette butts, considering them as possible sources of secondary raw materials applicable to contexts of common interest. Several papers were selected and the results obtained by the authors are presented in terms of type of treatment process (physical, chemical or both), product derived (in solid, liquid or gaseous form) and its possible use in different sectors (e.g. construction, electronics, energy, chemistry and environmental protection). The main results, together with the advantages and disadvantages are highlighted and proposals for further research are outlined.

2020 - Data on the environmental performance analysis of a dual-source heat pump system [Articolo su rivista]
Marinelli, S.; Butturi, M. A.; Lolli, F.; Rimini, B.; Gamberini, R.

This data article reports supplementary input and output data related to the research article “Environmental performance analysis of a dual-source heat pump system” on the life cycle assessment evaluation of an heat pump prototype, able to use alternatively the air and the ground as external heat sources. Primarily, the present article shows the life cycle inventory input data of the system under study and of the conventional air and ground heat pump systems, which were used for comparison. Secondly, complete numerical results are exposed, which are showed only graphically and in an aggregated form in the main article. Data include normalised and unaggregated environmental impacts of each investigated life cycle phase. The article also reports the complete results of the sensitivity analysis conducted using different assumptions on the energy mix and on the energy use.

2020 - Ecotoxicity of Plastics from Informal Waste Electric and Electronic Treatment and Recycling [Articolo su rivista]
Butturi, MARIA ANGELA; Marinelli, Simona; Gamberini, Rita; Rimini, Bianca

Plastic materials account for about 20% of waste electrical and electronic equipment (WEEE). The recycling of this plastic fraction is a complex issue, heavily conditioned by the content of harmful additives, such as brominated flame retardants. Thus, the management and reprocessing of WEEE plastics pose environmental and human health concerns, mainly in developing countries, where informal recycling and disposal are practiced. The objective of this study was twofold. Firstly, it aimed to investigate some of the available options described in the literature for the re-use of WEEE plastic scraps in construction materials, a promising recycling route in the developing countries. Moreover, it presents an evaluation of the impact of these available end-of-life scenarios on the environment by means of the life cycle assessment (LCA) approach. In order to consider worker health and human and ecological risks, the LCA analysis focuses on ecotoxicity more than on climate change. The LCA evaluation confirmed that the plastic re-use in the construction sector has a lower toxicity impact on the environment and human health than common landfilling and incineration practices. It also shows that the unregulated handling and dismantling activities, as well as the re-use practices, contribute significantly to the impact of WEEE plastic treatments.

2020 - Environmental performance analysis of a dual- source heat pump system [Articolo su rivista]
Marinelli, S.; Lolli, F.; Butturi, Maria Angela; Rimini, B.; Gamberini, R.

Using all phases of a life cycle assessment (LCA), this paper analyses the environmental impact of a dualsource heat pump (DSHP) system that uses either the air or the ground as external heat sources. Data on the production were provided by the manufacturer of the heat pump prototype. The use phase was considered by evaluating the seasonal and annual energy performance of the system, using dynamic simulations. The system maintenance and end-of-life were modelled in accordance with the current regulations and statistical data in this sector. The Ecoinvent database was used as a reference for background data. The ReCiPe, CED and IPCC 100a impact methods were used to assess the environmental impact categories. The results were compared with those of conventional air and ground source heat pump systems. A sensitivity study on the influence of the energy in the use phase was carried out in terms of a variation in energy use and for different energy mixes, including photovoltaic energy. The results demonstrated the environmental validity of the technology in comparison with the two conventional heat pumps used for residential applications in different conditions. The results could be used by heat pump manufacturers to improve the design and performance of their products, by designers in the selection of thermal technologies, and by researchers involved in the study of similar emerging renewable energy technologies.

2020 - Evaluating the environmental benefit of energy symbiosis networks in eco-industrial parks [Relazione in Atti di Convegno]
Marinelli, Simona; Butturi, MARIA ANGELA; Rimini, Bianca; Gamberini, Rita; Marinello, Samuele

In order to evaluate the environmental benefits of energy industrial symbiosis networks with the inclusion of renewable technologies, a model that minimises greenhouse gases emissions has been developed. A validation of the model has been carried out comparing the results with those calculated with a life cycle assessment of a reference case. The study demonstrates that energy industrial symbiosis networks integrating renewable energy technologies have the potential to significantly reduce greenhouse gases emissions and suggests a methodology to optimise energetic symbiosis connections inside eco-industrial parks.

2020 - Roadway tunnels: A critical review of air pollutant concentrations and vehicular emissions [Articolo su rivista]
Marinello, S.; Lolli, F.; Gamberini, R.

Air quality is a widespread problem with the presence of pollutants in indoor and outdoor environments that generate significant consequences for the population, ecosystems and exposed materials. Vehicular traffic is one of the main sources of air pollutants and, therefore, needs to be studied and analysed in detail. This review reported the results of studies conducted on tunnels, in particular for the measurement of concentrations and the definition of emission factors. The characteristics of the tunnels, available ventilation systems, type of vehicular traffic, and geographical distribution, in addition to concentrations and emission factors, are discussed. Light-duty vehicles are the most frequent category in the case studies. Between the fuels used, gasoline is by far the most widespread. Pollutant concentrations concentrations can reach very high levels. For example, atmospheric particulates (with an aerodynamic diameter of 10 µm) and nitrogen dioxide have also reached levels of 1490 µg/m3 and 4982 µg/m3, respectively.

2020 - The application of a Quality Function Deployment approach for the design of a B2B web platform [Relazione in Atti di Convegno]
Marinello, Samuele; Gamberini, Rita; Lolli, Francesco

2020 - Urban-industrial symbiosis to support sustainable energy transition [Articolo su rivista]
Butturi, MARIA ANGELA; Gamberini, Rita

Despite the growing interest in the field of urban–industrial symbiosis as well as in sustainable energy solutions at the city level, a research gap is recognized in terms of analyzing the advantages of energy symbiosis networks between industrial and urban areas integrating renewable energy systems. The urban–industrial symbiosis can support both urban transition toward sustainability and industrial green innovation through creating advantageous relationships in the framework of a common low-carbon strategy between industrial districts and neighboring urban areas. Urban–industrial symbiosis extends the concept of industrial symbiosis, a part of the industrial ecology field, to urban–industrial synergies. Taking advantage of the geographic proximity, it promotes the exchanges of waste, resources, and energy between urban and industrial areas, as well as the sharing of infrastructure. Thus, the paper aims at presenting an in-depth analysis of the main urban–industrial symbiosis schemes based on low-carbon energy flows between industries and cities, investigating the energy synergies potential. It introduces the concept and outline of sustainability-driven framework with the aim of modeling urban–industrial energy symbiosis networks integrating renewable energy sources from a multi-stakeholder point of view and supporting decision-making on the economic, environmental, and social sustainability of the energy synergies.

2019 - A periodic inventory system of intermittent demand items with fixed lifetimes [Articolo su rivista]
Balugani, Elia; Lolli, Francesco; Gamberini, Rita; Rimini, Bianca; Babai, M. Z.

Perishable items with a limited lifespan and intermittent/erratic consumption are found in a variety of industrial settings: dealing with such items is challenging for inventory managers. In this study, a periodic inventory control system is analysed, in which items are characterised by intermittent demand and known expiration dates. We propose a new inventory management method, considering both perishability and intermittency constraints. The new method is a modification of a method proposed in the literature, which uses a periodic order-up-to-level inventory policy and a compound Bernoulli demand. We derive the analytical expression of the fill rate and propose a computational procedure to calculate the optimal solution. A comparative numerical analysis is conducted to evaluate the performance of the proposed solution against the standard inventory control method, which does not take into account perishability. The proposed method leads to a bias that is only affected by demand size, in contrast to the standard method which is impacted by more severe biases driven by intermittence and periods before expiration.

2019 - Corrigendum to “Preparation for reuse activity of waste electrical and electronic equipment: Environmental performance, cost externality and job creation” (Journal of Cleaner Production (2019) 222 (77–89), (S0959652619306870), (10.1016/j.jclepro.2019.03.004)) [Articolo su rivista]
Pini, M.; Lolli, F.; Balugani, E.; Gamberini, R.; Neri, P.; Rimini, B.; Ferrari, A. M.

The authors regret some errors with the notation of decimals in tables 8, 11, 12, 13 and 14. Following, the authors report the correct number values per each of the above mentioned tables. Table 8 Repair time spent for preparing for reuse of WEEE.

2019 - Experimental plant for the cultivation of microalgae in photobioreactors for energy production [Relazione in Atti di Convegno]
Marinello, Samuele; Gamberini, Rita; Bastone, Loredana; Civitelli, Donatella; Buttafuoco, Gabriele; Gabriele Anna, Lia; Proietti, Luca; Vincenti, Enrico; Zarlenga, Gaetano; Vallerotonda, Martina; Femia, Stefano; Fuda, Giampietro; Lopresto, Catia; Calabrò, Vincenza; Arcuri, Natale; Bruno, Rosalinda

The continuous research of alternative and sustainable energy solutions with respect to fuels deriving from oil has led the current industrial and scientific system to analyze and develop approaches and technologies capable of enhancing materials of different nature for the production of biofuels. Algae are an alternative widely studied for this purpose, not only respect to the production of fossil fuels, but also respect to first-generation biofuels that use higher plants produced by normal cultivation methods. There are many plant solutions tested and disseminated internationally, operating in both outdoor and indoor environments. One of the most widespread criticisms is the inability to supply biodiesel quantities suitable for a production scale and with a positive economic and energy balance. This paper describes the results of a 4-years experimental research project oriented to the development of a low-scale demonstration plant of a complete advanced energy system based on the massive cultivation of microalgae and their treatment aimed at competitive production and sustainable bio-oil and biogas having requisites of suitability and compatibility with the relevant reference markets. The article intends to focus on a specific technological macro-component, completely studied and realized during the research project: the transparent, fully closed tubular photobioreactor (PBR) made of plastic material operating in continuous and in outdoor environments used for algal cultivation at low cost and high efficiency. The experimental plant was developed with the aim of providing a contribution to the main critical situations spread in this field, in particular: the need to reduce costs of the components of the plant and of the input resources necessary for the functioning of the system (energy, fertilizers, CO2, water, etc), as well as to maximize its modularity, reproducibility and exportability in other territorial contexts.

2019 - Life Cycle Thinking (LCT) applied to residential heat pump systems: A critical review [Articolo su rivista]
Marinelli, Simona; Lolli, Francesco; Gamberini, Rita; Rimini, Bianca

Heat pump technology is widely considered to be one of the promising opportunities for energy-efficient and low-carbon solutions for buildings and construction. However, sustainability is not always an intrinsic feature of all heat pumps. According to the Life Cycle Thinking approach, to assess the complete sustainability of a technology, a direct evaluation of the environmental, economic and social aspects over the entire life cycle is needed. Due to the growing interest in this technology, the present review summarizes the existing contributions on the sustainability of heat pump systems for residential heating and cooling using the Life Cycle environmental and Social Assessment and Life Cycle Costing. The main results are highlighted, then the data input, methodological assumptions and evaluation criteria are analyzed. The study reveals how to improve the sustainability of HP devices from a life cycle thinking approach.

2019 - Machine learning for multi-criteria inventory classification applied to intermittent demand [Articolo su rivista]
Lolli, F.; Balugani, E.; Ishizaka, A.; Gamberini, R.; Rimini, B.; Regattieri, A.

Multi-criteria inventory classification groups inventory items into classes, each of which is managed by a specific re-order policy according to its priority. However, the tasks of inventory classification and control are not carried out jointly if the classification criteria and the classification approach are not robustly established from an inventory-cost perspective. Exhaustive simulations at the single item level of the inventory system would directly solve this issue by searching for the best re-order policy per item, thus achieving the subsequent optimal classification without resorting to any multi-criteria classification method. However, this would be very time-consuming in real settings, where a large number of items need to be managed simultaneously. In this article, a reduction in simulation effort is achieved by extracting from the population of items a sample on which to perform an exhaustive search of best re-order policies per item; the lowest cost classification of in-sample items is, therefore, achieved. Then, in line with the increasing need for ICT tools in the production management of Industry 4.0 systems, supervised classifiers from the machine learning research field (i.e. support vector machines with a Gaussian kernel and deep neural networks) are trained on these in-sample items to learn to classify the out-of-sample items solely based on the values they show on the features (i.e. classification criteria). The inventory system adopted here is suitable for intermittent demands, but it may also suit non-intermittent demands, thus providing great flexibility. The experimental analysis of two large datasets showed an excellent accuracy, which suggests that machine learning classifiers could be implemented in advanced inventory classification systems.

2019 - On the elicitation of criteria weights in PROMETHEE-based ranking methods for a mobile application [Articolo su rivista]
Lolli, Francesco; Balugani, Elia; Ishizaka, Alessio; Gamberini, Rita; Butturi, Maria Angela; Marinello, Samuele; Rimini, Bianca

Today, almost everybody has a smartphone and applications have been developed to help users to take decisions (e.g. which hotel to choose, which museum to visit, etc). In order to improve the recommendations of the mobile application, it is crucial to elicit the preference structures of the user. As problems are often based on several criteria, multicriteria decision aiding methods are most adequate in these cases, and past works have proposed indirect eliciting approaches for multicriteria decision aiding methods. However, they often do not aim of reducing as much as possible the cognitive efforts required by the user. This is prerequisite of mobile applications as they are used by everybody. In this work, the weights to assign to the evaluation criteria in a PROMETHEE-based ranking approach are unknown, and therefore must be elicited indirectly either from a partial ranking provided by the user or from the selection of his/her most preferred alternative into a subset of reference alternatives. In the latter case, the cognitive effort required by the decision-maker is minimal. Starting from a linear optimisation model aimed at searching for the most discriminating vector of weights, three quadratic variants are proposed subsequently to overcome the issues arising from the linear model. An iterative quadratic optimisation model is proposed to fit the real setting in which the application should operate, where the eliciting procedure must be launched iteratively and converge over time to the vector of weights, which are the weights that the user implicitly assigns to the evaluation criteria. Finally, three experiments are performed to confirm the effectiveness and the differences between the proposed models.

2019 - Preparation for reuse activity of waste electrical and electronic equipment: Environmental performance, cost externality and job creation [Articolo su rivista]
Pini, Martina; Lolli, Francesco; Balugani, Elia; Gamberini, Rita; Neri, Paolo; Rimini, Bianca; Ferrari, Anna Maria

The European Waste Electrical and Electronic Equipment system introduced measures to encourage both the reduction of the amount of electronic waste and its separation to prepare for reuse. The aim of this study is compare the environmental performance, cost externality and job creation of the whole life cycle of new and reconditioned electrical and electronic equipment by adopting Life Cycle Assessment methodology. Five electrical and electronic equipment categories were investigated and the data collection was made on an Italian context. The refurbishing of breakdown electrical and electronic equipment was assessed by considering different sets of faulty components (Scenario A and B) and a total of 25 scenarios were studied. Moreover, both attributional and consequential life cycle inventory modelling framework were adopted to represent the investigated scenarios. The outcomes highlighted that the preparation for reuse process leads to obtaining a sustainable electronic device than the new one, depending on which set of components are replaced. Adopting Scenario B with the attributional model, the environmental damage of reconditioned electrical and electronic equipment decreases compared to the new one. Conversely, the consequential approach determines an environmental credit for all repaired electronic devices except for one category; in particular, Scenario A produced the largest environmental advantage. The analyses of external costs and social aspects confirm that the preparation for reuse activity allows to obtain a more sustainable product than a new one. For these two latter aspects, the results showed a turnaround passing from attributional model to consequential one. Noting the variability in results adopting both different life cycle inventory modelling framework and set of replaced components, the Life Cycle Assessment practitioner, that conducted the study, should help the decision-makers to determine which scenario is more sustainable accomplishing an adequate choice.

2019 - Quality cost-based allocation of training hours using learning-forgetting curves [Articolo su rivista]
Lolli, Francesco; Balugani, Elia; Gamberini, Rita; Rimini, Bianca

The training of suppliers and inbound quality inspectors is a common strategy to increase the quality performance of the supply chain but, under budget constraints, these actors compete for a limited amount of training hours. The proposed model aims to allocate the available training hours so as to minimise a total quality cost function composed of prevention, appraisal, and failure costs; it also sets the inspection rates defining the inspection policies assigned to suppliers. The relationship between decision variables and costs is expressed through organisational and individual learning-forgetting curves, for suppliers and quality inspectors respectively, and the effect of the training hours on quality improvement is measured in terms of failure rates. To the best of our knowledge, a total quality cost model with such decision variables is new in the related literature, as it is a model including both organisational and individual learning-forgetting phenomena. A nonlinear optimisation approach was adopted to solve this complex problem. The experimental section includes a decision trees analysis of simplified scenarios in order to interpret the model functioning, as well as a complex numerical example to extrapolate managerial insights.

2019 - Renewable energy in eco-industrial parks and urban-industrial symbiosis: A literature review and a conceptual synthesis [Articolo su rivista]
Butturi, M. A.; Lolli, F.; Sellitto, M. A.; Balugani, E.; Gamberini, R.; Rimini, B.

Replacing fossil fuels with renewable energy sources is considered as an effective means to reduce carbon emissions at the industrial level and it is often supported by local authorities. However, individual firms still encounter technical and financial barriers that hinder the installation of renewables. The eco-industrial park approach aims to create synergies among firms thereby enabling them to share and efficiently use natural and economic resources. It also provides a suitable model to encourage the use of renewable energy sources in the industry sector. Synergies among eco-industrial parks and the adjacent urban areas can lead to the development of optimized energy production plants, so that the excess energy is available to cover some of the energy demands of nearby towns. This study thus provides an overview of the scientific literature on energy synergies within eco-industrial parks, which facilitate the uptake of renewable energy sources at the industrial level, potentially creating urban-industrial energy symbiosis. The literature analysis was conducted by arranging the energy-related content into thematic categories, aimed at exploring energy symbiosis options within eco-industrial parks. It focuses on the urban-industrial energy symbiosis solutions, in terms of design and optimization models, technologies used and organizational strategies. The study highlights four main pathways to implement energy synergies, and demonstrates viable solutions to improve renewable energy sources uptake at the industrial level. A number of research gaps are also identified, revealing that the energy symbiosis networks between industrial and urban areas integrating renewable energy systems, are under-investigated.

2018 - A Fuzzy Logic Control application to the Cement Industry [Relazione in Atti di Convegno]
Sellitto, M. A.; Balugani, Elia; Gamberini, R.; Rimini, B.

A case study on continuous process control based on fuzzy logic and supported by expert knowledge is proposed. The aim is to control the coal-grinding operations in a cement manufacturing plant. Fuzzy logic is based on linguistic variables that emulate human judgment and can solve complex modeling problems subject to uncertainty or incomplete information. Fuzzy controllers can handle control problems when an accurate model of the process is unavailable, ill-defined, or subject to excessive parameter variations. The system implementation resulted in productivity gains and energy consumption reductions of 3% and 5% respectively, in line with the literature related to similar applications.

2018 - A human-machine learning curve for stochastic assembly line balancing problems [Relazione in Atti di Convegno]
Lolli, F.; Balugani, E.; Gamberini, R.; Rimini, B.; Rossi, V.

The Assembly Line Balancing Problem (ALBP) represents one of the most explored research topics in manufacturing. However, only a few contributions have investigated the effect of the combined abilities of humans and machines in order to reach a balancing solution. It is well-recognized that human beings learn to perform assembly tasks over time, with the effect of reducing the time needed for unitary tasks. This implies a need to re-balance assembly lines periodically, in accordance with the increased level of human experience. However, given an assembly task that is partially performed by automatic equipment, it could be argued that some subtasks are not subject to learning effects. Breaking up assembly tasks into human and automatic subtasks represents the first step towards more sophisticated approaches for ALBP. In this paper, a learning curve is introduced that captures this disaggregation, which is then applied to a stochastic ALBP. Finally, a numerical example is proposed to show how this learning curve affects balancing solutions.

2018 - Clustering for inventory control systems [Relazione in Atti di Convegno]
Balugani, E.; Lolli, F.; Gamberini, R.; Rimini, B.; Regattieri, A.

Inventory control is one of the main activities in industrial plant management. Both process owners and line workers interact daily with stocks of components and finite products, and an effective management of these inventory levels is a key factor in an efficient manufacturing process. In this paper the algorithms k-means and Ward's method are used to cluster items into homogenous groups to be managed with uniform inventory control policies. This unsupervised step reduces the need for computationally expensive inventory system control simulations. The performance of this methodology was found to be significant but was strongly impacted by the intermediate feature transformation processes.

2018 - DEASort: Assigning items with data envelopment analysis in ABC classes [Articolo su rivista]
Ishizaka, Alessio; Lolli, Francesco; Balugani, Elia; Cavallieri, Rita; Gamberini, Rita

Multi-criteria inventory classification groups similar items in order to facilitate their management. Data envelopment analysis (DEA) and its many variants have been used extensively for this purpose. However, DEA provides only a ranking and classes are often constructed arbitrarily with percentages. This paper introduces DEASort, a variant of DEA aimed at sorting problems. In order to avoid unrealistic classification, the expertise of decision-makers is incorporated, providing typical examples of items for each class and giving the weights of the criteria with the Analytic Hierarchy Process (AHP). This information bounds the possible weights and is added as a constraint in the model. DEASort is illustrated using a real case study of a company managing warehouses that stock spare parts.

2018 - Distributed renewable energy generation: a critical review based on the three pillars of sustainability [Relazione in Atti di Convegno]
Butturi, MARIA ANGELA; Lolli, Francesco; Balugani, Elia; Gamberini, Rita; Rimini, Bianca

Reducing emissions responsible for the climate change is recognized as a strategic goal at European and global level. A higher deployment of renewable energy sources is considered as essential for a low-carbon transition, towards a more sustainable energy system. The 2030 Framework for Climate and Energy sets out the European Union target for 2030 of at least 27% for the share of renewable energy consumption. A high share of renewables requires a new flexible and integrated electricity system to ensure grid stability and match supply and demand. The advances in technologies for renewable electricity and heating production, efficient storage solutions, and advanced ICT allow flexible electrical infrastructures: distributed renewable energy generation is now widely recognized as the main pathway towards an effective integration of discontinuous sources into the energy system. The discussion on renewable energy sources introduction in the energy system has long been focused on technical, economic and policy issues, but the transition to a distributed renewable energy generation approach demands a change of perspective, considering a multi-sectoral sustainability view and the need for multi-stakeholder action. Purpose of this research is reviewing the more recent scientific papers on the distributed renewable energy generation approach, focusing on how all the three key sustainability dimensions, environmental, economic and social, are evaluated and managed in a multi-criteria perspective. The sustainability indicators suggested in literature are classified and discussed to build up an up-to-date and comprehensive set of sustainability related criteria, suitable for future research applications and for supporting decision making processes.

2018 - New and Reconditioned Electrical and Electronic Equipment. How does change the environmental performance? [Abstract in Atti di Convegno]
Pini, Martina; Neri, Paolo; Gamberini, Rita; Rimini, Bianca; Lolli, Francesco; Ferrari, Anna Maria

The scope of this study, carried out within the LIFE12 ENV/IT001058 - "WEEENmodels" project, was to compare the environmental performance of the life cycle of new electrical and electronic equipment (EEE) and the reused one through the Life Cycle Assessment (LCA) methodology. Different set of replaced components have been evaluated in order to understand which determines the best solution. Finally, both attributional and consequential LCI (Life Cycle Inventory) modelling have been implemented. A representative product has been considered for each WEEE group, assuming that it generates the same environmental damage of the other products belonging to the same category. In particular, the following representative products have been selected: refrigerator (R1), washing machine (R2), cathode ray tube (CRT) (R3), laptop (R4) and fluorescent lamp (R5). In addition, in the use phase, lower performance of reconditioned EEE has been taken into account, e.g. higher energy consumptions. The lifespan of the reused product has been supposed to be equal to half-life time of an equivalent new product. This study evaluated different set of replaced components for each WEEE category in order to examine how the environmental performance can vary adopting different maintenance choices in the reconditioning step. In particular, Scenario A represents the set of replaced components, which damage more frequently; Scenario B is just an alternative set of replaced components. The environmental comparison between new and reused WEEE, adopting attributional LCI modelling, showed that Scenario B produces a damage decrease for all WEEE categories. Moving on the consequential LCI modelling, the environmental comparison highlighted for both scenarios a considerable damage reduction for the reused EEE respect the new one. In addition, Scenario B determined the best environmental performance. Furthermore, for the reused R1, R2, R3 the analysis of results carried out environmental credits. This is due to the avoided burdens associated to the manufacturing of the new EEE, since the system boundaries have been enlarged until to considering the avoided production of the new product. Attributional and consequential LCI modelling performed different LCIA results. Following the methodological guidance for the identification of the most adequate LCI modelling framework presented by Laurent et al., 2014, it would recommend to adopt consequential LCI modelling. But we suggest to LCA practitioner to focus also the attention on the request of who commissioned the project, which often in the waste field are local administrations. Generally, they wants a snapshot of the real effects that waste management policies provoke on human health and environment. For this reason, attributional LCI modelling would be the proper LCI modelling to achieve this scope. Considering this LCI modelling the Scenario B determines the best environmental performance.

2018 - Novel biocompatible PBS-based random copolymers containing PEG-like sequences for biomedical applications: From drug delivery to tissue engineering [Articolo su rivista]
Fabbri, M.; Guidotti, G.; Soccio, M.; Lotti, N.; Govoni, M.; Giordano, E.; Gazzano, M.; Gamberini, R.; Rimini, B.; Munari, A.

A series of random poly(butylene succinate)-based copolymers, (poly(butylene/triethylene succinate) (P(BSmTESn)), containing ether-oxygen atoms were successfully synthesized by melt polycondensation of succinic acid and 1,4-butanediol in the presence of triethylene glycol (TEG) (TEG content up to 40 mol%). The copolymers were characterized from the molecular, thermal, structural and mechanical point of view. Hydrolytic degradation studies were performed under physiological conditions. The biocompatibility of the samples under investigation through indirect and direct biocompatibility studies was investigated by using embryonic rat cardiac H9c2 cells. To evaluate the potential of these polymers also for controlled drug delivery systems, the diffusion profile of Dexamethasone, an anti-inflammatory drug, through nanoparticles prepared by oil-in-water miniemulsion process was investigated. Results showed that solid-state properties could be tailored nicely by simply varying copolymer composition. Crystallinity degree and hydrophobicity significantly decreased with the increase of triethylene succinate co-unit (TES) mol%. Moreover, hydrolytic degradation of PBS, depending on polymer crystallinity degree and hydrophilicity, was remarkably improved: the copolymer containing 40 mol% of triethylene succinate co-unit after 200 days lost over 22% of its initial weight. The newly developed biomaterials showed lack of cell cytotoxicity. Among them, PBS and the copolymers containing up to 20 mol% of TES co-units sustained a better cell adhesion and proliferation. In addition, such copolymers induced muscle phenotype commitment in H9c2 cells cultured onboard. Lastly, the release profile of Dexamethasone obeyed to a first order kinetic law, the copolymer richest in TES co-unit content showing the highest encapsulation capability and the fastest drug release kinetics. Anyway, PBS and the copolymers containing up to 20 mol% of TES co-unis sustained a better cell adhesion and proliferation, with the copolymers characterized by a myosin heavy chain expression, which appeared to be up to twofold increased on respect to the one of PBS homopolymer.

Gamberini, R.; Ruggerini, T.; Lolli, F.

The problem of studying a plant layout is frequently tackled in literature. Nevertheless, approaches specifically dedicated to predefined market fields are rare. Usually, methodologies available for a wide variety of companies are studied and adopted, disregarding those details typical of each economical sector. On the contrary, in this paper, customized guidelines for the design of a plant layout of a foundry are proposed, in order to support such a critical productive environment where automated equipment, characteristic of Industry 4.0, are integrated with manual activities. Specifically, the casting area is studied. The long term design is supported by a medium term analysis, focused on the products turnover into the casting moulds. The application to a real life case study is finally described in order to assess the performance of the proposed approach.

2018 - The training of suppliers: A linear model for optimising the allocation of available hours [Articolo su rivista]
Lolli, Francesco; Gamberini, Rita; Gamberi, Mauro; Bortolini, Marco

The cost of quality represents a relevant item in total manufacturing costs. The learning process is incorporated into contemporary models because of its impact on unitary production costs through both autonomous (learning by doing) and induced (learning by means of proactive actions) learning processes. A learning model with time-varying learning rate is proposed in order to establish the relationship between quality improvements and training hours to allocate to suppliers. The performance indicator adopted is the rate of non-conforming units, rather than the more traditional process variance. This enables definition of a novel total cost function, which can be minimised for the best allocation of training hours to suppliers during a single learning cycle. A novel criterion also emerges for the evaluation of suppliers in terms of investment opportunity. Finally, a case study was carried out in order to verify the applicability of this model to real industrial settings.

2017 - A multicriteria framework for inventory classification and control with application to intermittent demand [Articolo su rivista]
Lolli, Francesco; Ishizaka, Alessio; Gamberini, Rita; Rimini, Bianca

Several papers have studied inventory classification in order to group items with a view to facilitating their management. The generated classes are then coupled with the specific reorder policies composing the overall inventory control system. However, the effectiveness of inventory classification and control system is strictly interrelated. That is to say, different classification approaches could show different performance if applied to a different set of reorder policies, and vice versa. Furthermore, when the cost structure is subjected to uncertainty, a pure cost-based analysis of the inventory control system could be corrupted. This paper presents a multicriteria framework for the concurrent selection of the item classification approach and the inventory control system through a discrete-event simulation approach. The key performance indicators provided by the simulator (i.e., average holding value, average number of backorders, and average number of emitted orders) are indicative of the multidimensional effectiveness of the adopted inventory control system when coupled with a specific classification approach. By this way, a multicriteria problem arises, where the alternatives are given by exhaustively coupling the item classes, which are generated by different classification approaches, with the reorder policies composing the inventory system. An analytical hierarchy process is then used for selecting the best alternative, as well as for evaluating the effect of the weights assigned to the key performance indicators through a sensitivity analysis. This approach has been validated in a real case study with a company operating in the field of electrical resistor manufacturing, with a view of facilitating the management of items showing intermittent demand.

2017 - AHP-K-GDSS: A new sorting method based on AHP for group decisions [Relazione in Atti di Convegno]
Ishizaka, Alessio; Lolli, Francesco; Gamberini, Rita; Rimini, Bianca; Balugani, Elia

Some public buildings need for energy requalification intervention as they are responsible for a significant share of energy consumption and other related CO2 emissions. With tight budget constraints choices have to be made. To solve this problem a group sorting decision support system based on the analytic hierarchy process, the Kmeans algorithm has been developed. The system aims at sorting alternatives into ordered classes of importance. A case study carried out in an Italian municipality allowed us to verify the validity of our new method in a real setting.

2017 - Decision Trees for Supervised Multi-criteria Inventory Classification [Relazione in Atti di Convegno]
Lolli, Francesco; Ishizaka, Alessio; Gamberini, Rita; Balugani, Elia; Rimini, Bianca

A multi-criteria inventory classification (MCIC) approach based on supervised classifiers (i.e. decision trees and random forests) is proposed, whose training is performed on a sample of items that has been previously classified by exhaustively simulating a predefined inventory control system. The goal is to classify automatically the whole set of items, in line with the fourth industrial revolution challenges of increased integration of ICT into production management. A case study referring to intermittent demand patterns has been used for validating our proposal, and a comparison with a recent unsupervised MCIC approach has shown promising results.

2017 - FMECA-based optimization approaches under an evidential reasoning framework [Relazione in Atti di Convegno]
Lolli, F.; Gamberini, R.; Balugani, E.; Rimini, B.; Mai, Francesco

One of the major shortcomings of traditional failure modes, effects and criticality analysis is the absence of any interconnection between failure ranking and a procedure for selecting the most critical maintenance/improvement tasks to be carried out. This limits the potential of FMECA for implementation in real environments. In order to bridge this gap, three different 0-1 knapsack models have been formulated. The first aims to select the failures in order to maximise cost savings. The second enriches the selection problem by also taking into account the probabilities of solving the failures with a set of maintenance tasks. The third aims to select the maintenance tasks to maximise the expected profit. In particular, the last two models make use of an evidential reasoning framework to deal with the epistemic uncertainty related to these probabilities. A dataset from a manufacturer of lift winches has been used to validate this proposal, as well as to comment on the need for group decision support systems that are capable of converting the FMECA ranking into maintenance tasks in real environments.

2017 - Health Risk Assessment per esposizione occupazionale a sostanze chimiche cancerogene e non cancerogene nel riciclo di rifiuti di apparecchiature elettriche e elettroniche (RAEE): dati dal progetto WeeenModels. [Abstract in Atti di Convegno]
Modenese, A; Ferrari, Am; Gamberini, R; Grasselli, L; Neri, P; Pini, M; Rimini, B; Vinceti, M; Violi, F; Gobba, F.

Health Risk Assessment per esposizione occupazionale a sostanze chimiche cancerogene e non cancerogene nel riciclo di rifiuti di apparecchiature elettriche e elettroniche (RAEE): dati dal progetto WeeenModels.

2017 - Inventory control system for intermittent items with perishability [Relazione in Atti di Convegno]
Balugani, E.; Lolli, F.; Gamberini, R.; Rimini, B.

Perishable items, with a limited lifespan and a known expiration date, are found in a variety of industrial settings. From the food to the pharmaceutical industries, the supply chains specialize their inventory control systems to handle the added complexity. These efforts are enhanced when the items present also an intermittent consumption, characterized by frequent periods without demand mixed to highly variable positive demand events. In this paper, a novel periodic inventory control system aims at bridging the gap between these two product features, managing intermittent items with expiration dates. The proposed system performs a combinatorial analysis evaluating all the demand scenarios before and after an expiration date to measure the expected fill rate. An optimization algorithm then sets the order quantity, using mathematical properties of the system to define efficient search boundaries.

2017 - Life Cycle Assessment of a Nano-TiO2 Functionalized Enamel Applied on a Steel Panel [Articolo su rivista]
Pini, Martina; Neri, Paolo; Gamberini, Rita; Rimini, Bianca; Marinelli, Simona; Ferrari, Anna Maria

In the building sector today, enamelled steel products are largely used because of their longevity and aesthetic qualities. In recent years, the considerable improvement in the chemical frit composition for enamelling has led to the development of TiO2 nanoparticle functionalized coatings. Thanks to the photo-catalytic and super-hydrophilic properties of TiO2, it is possible to obtain both self-cleaning and self-sterilizing surfaces. The benefits of these nanoparticles were substantiated, but their risk to the environment and human health is still being assessed. This study analyses the environmental performance of enamelled steel panels that are nano-TiO2 functionalized, using a life cycle assessment methodology. It applies the previously defined (but still preliminary) human toxicity indicators for TiO2 nanoparticles to the life cycle impact assessment (LCIA) stage, representing an early attempt to evaluate the human health risks caused by these new materials through LCA study.

2017 - Micro-structured 3D-electrospun scaffolds of biodegradable block copolymers for soft tissue regeneration [Articolo su rivista]
Fabbri, M.; García-Fernández, L.; Vázquez-Lasa, B.; Soccio, M.; Lotti, N.; Gamberini, R.; Rimini, B.; Munari, A.; San Román, J.

The present article describes the application of a poly(ethylene terephthalate) mesh as template for the preparation of micro-structured fibres mat by electrospinning of biodegradable triblock copolymers based on polylactic acid and poly(butylene succinate/azelate) random copolymer. These copolymers present and excellent controlled biodegradation process in physiological conditions, with interesting applications in targeting and controlled release of different drugs. After the application of the poly(ethylene terephthalate) mesh in the electrospinning process, the detachment of the template provides a specific oriented microfibres mat, that affect to the adhesion and proliferation of cell seeded on the networks. In addition, the microfibres mats were loaded with dexamethasone as anti-inflammatory drug. The release of the drug takes place in a controlled relative short period due to the formation of drug crystals on the surface of the fibres during the electrospinning process. This issue can be restrained by acting on the triblock copolymer composition, improving the drug-polymer compatibility. Copolymerization also allows the modulation of the biodegradation rate. The biodegradable scaffolds under investigation can be therefore considered very promising for regenerative medicine and soft tissue engineering.

2017 - On the Analysis of Effectiveness in a Manufacturing Cell: A Critical Implementation of Existing Approaches [Articolo su rivista]
Gamberini, Rita; Galloni, Luca; Lolli, Francesco; Rimini, Bianca

OEE (Overall Equipment Effectiveness) is a widely used indicator in the evaluation of effectiveness of manufacturing systems. However, several authors published alternative approaches for its computation, complicating the implementation step for practitioners. This study analyses the literature regarding OEE, selects four main methodologies for its evaluation and examines the underlying differences between them. A real life case study is analysed to illustrate problems arising during data collection and the differences in results obtained, together with traceable conclusions for improving the performance of production systems, both in traditional and in innovative industrial plants, following Industry 4.0 principles.

2017 - Requalifying public buildings and utilities using a group decision support system [Articolo su rivista]
Lolli, Francesco; Ishizaka, Alessio; Gamberini, Rita; Rimini, Bianca; Balugani, Elia; Prandini, Laura

Public buildings and utilities are responsible for a significant share of energy consumption and other related CO2 emissions. There is therefore an acute need for energy requalification interventions. Unfortunately, municipalities are under tight budget constraints, but decisions have to be made. A new hybrid group decision support system has been proposed in a bid to provide them with firm, transparent support. The system is based on a combination of the analytic hierarchy process, the K- means algorithm, and the 0-1 knapsack model. The first two methods aim at sorting alternatives into ordered classes of importance. To help in this task, the Bezier curve-fitting approach is used to construct the preference functions of decision-makers based on reference points. Then, the knapsack model selects the alternatives from the generated classes while complying with the budget constraints. A case study carried out in an Italian municipality allowed us to verify the validity of our new method in a real setting, and to highlight the advantages of an automatic sorting procedure in practice.

2017 - Single-hidden layer neural networks for forecasting intermittent demand [Articolo su rivista]
Lolli, Francesco; Gamberini, Rita; Regattieri, A.; Balugani, Elia; Gatos, T.; Gucci, S.

Managing intermittent demand is a vital task in several industrial contexts, and good forecasting ability is a fundamental prerequisite for an efficient inventory control system in stochastic environments. In recent years, research has been conducted on single-hidden layer feedforward neural networks, with promising results. In particular, back-propagation has been adopted as a gradient descent-based algorithm for training networks. However, when managing a large number of items, it is not feasible to optimize networks at item level, due to the effort required for tuning the parameters during the training stage. A simpler and faster learning algorithm, called the extreme learning machine, has been therefore proposed in the literature to address this issue, but it has never been tried for forecasting intermittent demand. On the one hand, an extensive comparison of single-hidden layer networks trained by back-propagation is required to improve our understanding of them as predictors of intermittent demand. On the other hand, it is also worth testing extreme learning machines in this context, because of their lower computational complexity and good generalisation ability. In this paper, neural networks trained by back-propagation and extreme learning machines are compared with benchmark neural networks, as well as standard forecasting methods for intermittent demand on real-time series, by combining different input patterns and architectures. A statistical analysis is then conducted to validate the best performance through different aggregation levels. Finally, some insights for practitioners are presented to improve the potential of neural networks for implementation in real environments.

2017 - Stochastic assembly line balancing with learning effects [Relazione in Atti di Convegno]
Lolli, Francesco; Balugani, Elia; Gamberini, Rita; Rimini, Bianca

Human learning is nowadays taken into account in several research fields, including the assembly line balancing problem. Despite the plethora of contributions and different approaches to solving the problem, the autonomous learning phenomenon, that is to say, the time-dependent or position-dependent reduction of assembly task times due to repetition, should also be explored using stochastic models which, to the best of our knowledge, have been disregarded. In this paper, a well-established cost-based stochastic balancing heuristic has been coupled with a time-dependent learning curve in order to investigate the role of learning in the rebalancing of assembly lines with repetitive tasks. Finally, a real case study has been conducted with the aim of demonstrating the applicability of our proposal.

2016 - A learning model for the allocation of training hours in a multistage setting [Articolo su rivista]
Lolli, Francesco; Gamberini, Rita; Giberti, Claudio; Gamberi, Mauro; Bortolini, Marco; Bruini, Emanuele

In line with the continuous improvement theory, the learning phenomenon is often incorporated into models for predicting the evolution of the unitary quality costs. In this paper, the quality metric predicted is the rate of supplied non-conforming units through a learning process with autonomous and induced sources of experience. The former is simply learning by doing, i.e. supplying, whilst the latter is driven by the allocation of training hours to suppliers. A revised learning model with time-varying learning rates is proposed for embracing both these effects into a multistage assembly/production setting. A single-period prevention–appraisal–failure cost function is achieved, and the sample inspection rates adopted among suppliers are also considered in order to evaluate their effect. If these sample rates are given, the goal of allocating the training hours among suppliers is pursued by means of integer linear programming. Otherwise, a mixed-integer quadratic problem arises for the concurrent allocation of training hours and inspection sample rates among suppliers. A case study is finally carried out for demonstrating the applicability of the model, as well as for providing managerial insights.

Lolli, Francesco; Gamberini, Rita; Pulga, Francesco; Rimini, Bianca

This paper aims to present a modified failure mode and effects analysis (FMEA) in order to make the assignment of the scores for the occurrence factor more robust, and to link the FMEA chart directly to the maintenance activities. A well-known clustering algorithm (i.e. K-Means), along with a normalisation approach, are applied and compared for the assignment of the occurrence scores. Subsequently, the relationship between failures and maintenance operations is made explicit by a correlation matrix. Finally, the K-Means algorithm is applied to the maintenance operations again in order to sort them into priority classes. It is found that this revised FMEA approach improves the standard one due to its more rigorous mathematical formulation and lean applicability in real operating environments. A real case study is introduced in order to show the applicability of this approach to the quality control of a blow moulding process. It is found that this approach reveals a high potentiality for dealing with real issues. The paper provides a further step towards bridging the gap between theory and practical application of the FMEA approach.

2016 - A simulative approach for evaluating alternative feeding scenarios in a kanban system [Articolo su rivista]
Lolli, Francesco; Gamberini, Rita; Giberti, Claudio; Rimini, Bianca; Bondi, Federica

In accordance with the lean production philosophy, an assembly line may be supplied by means of a kanban system, which regulates and simplifies the flow of materials between the lines and the warehouses. This paper focuses on evaluation of feeding policies that differ from each other in term of the number of kanbans managed per feeding tour. A pure cost-based approach is thus proposed, which considers both inline inventories along with handling costs proportionate to the number of operators involved in the parts-feeding process. A multi-scenario simulative approach is applied in order to establish the number of operators required to avoid inline shortages. The scenario minimising total cost is then selected. The innovation introduced is a model for describing kanban arrivals and their requests for feeding, improving the potential of the simulation to describe real-life environments. Lastly, a case study from the automotive industry is presented in order to highlight the applicability of the proposed approach as well and the effects of alternative feeding policies on the total cost incurred.

2016 - An international partnership for the sustainable development of municipal solid waste management in Guinea-Bissau, West Africa [Relazione in Atti di Convegno]
Ferrari, Katia; Cerise, Streng; Gamberini, Rita; Rimini, Bianca

Most of the developing countries are facing great challenges to manage the increasing quantity of waste produced in the urban areas, that are growing at a very high rate. This paper presents the preliminary results of a technical study aiming at designing the first municipal master plan for the management of urban solid waste in the capital city of Guinea-Bissau, through a sustainable development international partnership. The project is led by the municipality of Bissau. It involves an Italian private enterprise, responsible for the technical transfer of knowledge and experience and count with the support of an international association, which plays the role of cultural bridge to guarantee the translation of innovative knowledge in local and feasible solutions for the African country. The final product of this international partnership should be a master plan, capable to design the waste management strategy for Bissau for the next 10 years, based on accurate data collected about the production and composition of waste in Bissau. The plan would be able to support the local policy makers to create an integrated waste management system, proper for the local characteristics and challenges. Irregular collection service, due to the lack of financial resources, together with a week awareness of the local population about the health and environmental risks related with the current practice of open dumping and burning are the major constrains. The identification of a proper location for a sanitary landfill to substitute the open dumpsite actually used to dispose the unsorted waste, the implementation of an efficient and economically feasible collection system are the current priorities. Future efforts should envisage how to improve and formalize the recycling and reusing activities, that have been realized nowadays informally by waste pickers in armful conditions.

2016 - Analisi LCA di un possibile scenario di riuso delle apparecchiature elettriche ed elettroniche dismesse: il progetto WEEENMODELS [Relazione in Atti di Convegno]
Pini, Martina; Gamberini, Rita; Lolli, Francesco; Neri, Paolo; Rimini, Bianca; Signori, Alessandra; Ferrari, Anna Maria

Il sistema europeo di raccolta dei rifiuti da apparecchiature elettriche ed elettroniche (RAEE) ha introdotto misure volte a incentivare la separazione dei RAEE da preparare per il riutilizzo. Obiettivo dello studio, svolto nell’ambito del progetto LIFE12 ENV/IT001058 – “WEEENMODELS”, è la valutazione ambientale di un possibile scenario di riuso di apparecchiature elettriche ed elettroniche dismesse e l’elaborazione di un calcolo approssimato per valutare gli effetti locali e indoor delle emissioni da esso generate.

2016 - Assessing cancer risk from heavy metal exposure in recycling waste of electrical and electronic equipment: preliminary results from the Weeenmodels European Life Programme. [Abstract in Atti di Convegno]
Violi, Federica; Modenese, Alberto; Gobba, Fabriziomaria; Ferrari, Anna Maria; Rimini, Bianca; Gamberini, Rita; Pini, M; Neri, P; Filippini, Tommaso; Grasselli, Luigi; Montanari, P; Vinceti, Marco

Introduction The growing amount of waste derived from electrical and electronic equipment (WEEE) poses significant challenges to waste management, due to the presence of toxic chemicals with environmental and health implications for the general population and for occupationally-exposed workers. Methods Based on an toxicological and epidemiologic evaluation, we carried out a health risk assessment to evaluate the cancer risk deriving from environmental and occupational exposure to heavy metals released during different WEEE recycling procedures (electronic scrap in blister copper, treatment of metals recovery in copper smelter, treatment of shredding, pyrometallurgical treatment of Li-ion battery). We considered the typical WEEE production in a municipality of 150.0000 inhabitants, carrying out a Life Cycle Assessment. Outdoor (1km2 around a treatment plant) and indoor (for a factory volume of 3200m3) emissions generated during the WEEE recycling procedures were computed. In particular, we estimated the amount of Cd, Ni and As inhaled by the potentially exposed population. We computed the cancer risk due to inhalation of these heavy metals in residents and workers using the methodology proposed by the California Office of Environmental Health and Hazard Assessment Results For the metals considered, our results showed negligible cancer risk (from 2,21x10-11 to 4,31x10-08) for the general population around the plant. On the converse, occupational exposures linked to specific procedures were associated with a cancer risk of 1,42x10-3 for workers in the shredding procedures mainly due to Ni exposure, and of 4,68x10-4 for workers with electronic scrap and exposed to As. Conclusions Based on our preliminary results from an integrated toxicological and epidemiologic approach, WEEE life cycle may be linked to health risks for workers in the recycling procedures, while it does not seem to adversely affect health of the general population around the treatment plants.

2016 - Assessing Cancer Risk from Heavy Metals in Recycling Waste Electrical and Electronic Equipment: Preliminary Results from the WEENMODELS European Life Programme [Abstract in Rivista]
Violi, Federica; Modenese, Alberto; Gobba, Fabriziomaria; Ferrari, Anna Maria; Rimini, Bianca; Gamberini, Rita; Pini, Martina; Neri, Paolo; Filippini, Tommaso; Grasselli, Luigi; Montanari, Pinuccia; Vinceti, Marco

Introduction The growing amount of waste derived from electrical and electronic equipment (WEEE) poses significant challenges to waste management, due to the presence of toxic chemicals with environmental and health implications for the general population and for occupationally-exposed workers. Methods Based on an toxicological and epidemiologic evaluation, we carried out a health risk assessment to evaluate the cancer risk deriving from environmental and occupational exposure to heavy metals released during different WEEE recycling procedures (electronic scrap in blister copper, treatment of metals recovery in copper smelter, treatment of shredding, pyrometallurgical treatment of Li-ion battery). We considered the typical WEEE production in a municipality of 150.0000 inhabitants, carrying out a Life Cycle Assessment. Outdoor (1 square km around a treatment plant) and indoor (for a factory volume of 3200 m3) emissions generated during the WEEE recycling procedures were computed. In particular, we estimated the amount of Cd, Ni and As inhaled by the potentially exposed population. We computed the cancer risk due to inhalation of these heavy metals in residents and workers using the methodology proposed by the California Office of Environmental Health and Hazard Assessment Results For the metals considered, our results showed negligible cancer risk (from 2,21x10-11 to 4,31x10-08) for the general population around the plant. On the converse, occupational exposures linked to specific procedures were associated with a cancer risk of 1,42x10-3 for workers in the shredding procedures mainly due to Ni exposure, and of 4,68x10-4 for workers with electronic scrap and exposed to As. Conclusions Based on our preliminary results from an integrated toxicological and epidemiologic approach, WEEE life cycle may be linked to health risks for workers in the recycling procedures, while it does not seem to adversely affect health of the general population around the treatment plants.

Violi, Federica; Modenese, Alberto; Gobba, Fabriziomaria; Ferrari, Anna Maria; Rimini, Bianca; Gamberini, Rita; Pini, Martina; Neri, Paolo; Filippini, Tommaso; Grasselli, Luigi; Montanari, Pinuccia; Vinceti, Marco

Background and objectives: When electrical and electronic equipment reaches its end of life, it becomes ‘Waste Electrical and Electronic Equipment’ (WEEE). The growing amount of this type of waste has posed significant challenges to waste management, since WEEE contains a whole range of toxic chemicals having relevant environmental and health implications. The WEEE life cycle may expose the general population and workers to various toxic chemicals, such as heavy metals. We conducted a health risk assessment to evaluate the cancer risk derived from environmental and occupational exposure to trace elements from different recycling procedures (electronic scrap in blister copper, treatment of metals recovery in copper smelter, treatment of shredding, pyrometallurgical treatment of Li-ion battery). We considered the typical production of WEEE in a municipality of 150.0000 inhabitants, where a Life Cycle assessment (LCA) was carried out. Methods: Outdoor (1km2 around a WEEE treatment plant) and indoor (factory volume of 3200m3) emissions generated from the above-mentioned procedures were computed, to perform a health risk assessment for occupationally-exposed workers and for the general population around the plant. Dose of the heavy metals cadmium, nickel, arsenic inhaled by the potentially exposed population was estimated using the values obtained through a toxicological model. Cancer risk due to inhalation was calculated using the method proposed by the California Office of Environmental Health and Hazard Assessment. Results and Conclusions: For the heavy metals considered, generated from WEEE treatment, these preliminary results show negligible cancer risk for the general population. On the converse, some risks may be present for occupational exposures linked to specific procedures (from cancer risk of 1,42x10-3 for men working in shredding procedure and exposed to nickel to cancer risk of 4,68x10- 4 for women working with electronic scrap and exposed to arsenic).

2016 - Design of fully aliphatic multiblock poly(ester urethane)s displaying thermoplastic elastomeric properties [Articolo su rivista]
Fabbri, Martina; Soccio, Michelina; Gigli, Matteo; Guidotti, Giulia; Gamberini, Rita; Gazzano, Massimo; Siracusa, Valentina; Rimini, Bianca; Lotti, Nadia; Munari, Andrea

By the combination of prepolymers with very different physical/chemical properties, better performance materials can be obtained. In the present study, three hydroxyl-terminated fully aliphatic polyesters have been chain extended to prepare new multiblock poly(ester urethane)s (PEU) displaying thermoplastic elastomeric characteristics. Poly(butylene succinate), poly(1,4-cyclohexylenedimethylene-1,4-cyclohexanedicarboxylate), and poly(neopentyl glycol adipate) have been respectively used as soft-hard, hard and soft segment. The evaluation of molecular, thermal, and mechanical properties and hydrolytic degradation profile permitted to correlate the behavior of the so-obtained materials with their molecular structure, and highlighted that it is possible to nicely tune the final characteristics of this class of PEUs by just varying the mutual amount of the three segments.

2016 - Esposizione occupazionale negli addetti alle attività di riciclo e riuso dei rifiuti di apparecchiature elettriche e elettroniche (RAEE): dati preliminari dal progetto WEEENMODELS. [Abstract in Atti di Convegno]
Modenese, A.; Violi, F.; Pini, M.; Gioia, T. C.; Ferrari, A. M.; Gamberini, R.; Grasselli, L.; Montanari, G.; Neri, P.; Rimini, B.; Vinceti, M.; Gobba, F.

Esposizione occupazionale negli addetti alle attività di riciclo e riuso dei rifiuti di apparecchiature elettriche e elettroniche (RAEE): dati preliminari dal progetto WEEENMODELS.

2016 - Key strategic actions to improve the challenge of hazardous waste management in Mozambique [Articolo su rivista]
Ferrari, Katia; Gamberini, Rita; Rimini, Bianca; Abacassamo, Hafido

Waste management is an international issue with a global impact. Industrialised and emerging countries increasingly need raw materials to feed their industries: natural gas, oil, coal, precious minerals and metals. Most African countries are rich in raw materials, which they are powerless to trade on but eager to negotiate with. However, they have difficulty managing the negative effect that these trades produce, due to poor environmental regulations, inadequate waste disposal infrastructures, lack of technology and public bodies with little experience and resources. This situation makes it challenging for some African governments to manage the increasing quantity and types of waste, resulting from the extracting industries and growing urbanization. Furthermore, the benefits are not fairly distributed, whilst the negative impacts, both environmental and socio-economic, of a failing waste management system are widespread and global. We have studied the situation of hazardous waste management in Mozambique as a case study. Mozambique is one of the poorest countries in the world, but is rich in natural resources, which are being exploited by several global companies in recent years, and with insufficient waste management infrastructure. After the analysis of the local condition, this paper aims to trace guidelines to support different stakeholders to make the first coordinated steps towards a better management of hazardous waste.

2016 - Modelling production cost with the effects of learning and forgetting [Relazione in Atti di Convegno]
Lolli, Francesco; Messori, Michael; Gamberini, Rita; Rimini, Bianca; Balugani, Elia

Defining a dynamic model for calculating production cost is a challenging goal that requires a good fitting ability with real data over time. A novel cost curve is proposed here with the aim of incorporating both the learning and the forgetting phenomenon during both the production phases and the reworking operations. A single-product cost model is thus obtained, and a procedure for fitting the curve with real data is also introduced. Finally, this proposal is validated on a benchmark dataset in terms of mean square error.

2016 - New fully bio-based PLLA triblock copoly(ester urethane)s as potential candidates for soft tissue engineering [Articolo su rivista]
Fabbri, Martina; Soccio, Michelina; Costa, Michela; Lotti, Nadia; Gazzano, Massimo; Siracusa, Valentina; Gamberini, Rita; Rimini, Bianca; Munari, Andrea; García Fernández, Luis; Vázquez Lasa, Blanca; San Román, Julio

Novel fully bio-based poly(lactic acid) copoly(ester-urethane)s have been successfully synthesized. The new system is composed of a series of A-B-A triblock copolymers, where A, hard block, is poly(lactic acid) and B, soft block, is an ad hoc designed random aliphatic copolyester, poly(butylene succinate/azelate), characterized by high flexibility. Triblock units are joined by hexamethylene diisocyanate, known chain extender that allows the obtaining of polymers with high molecular weights. The samples synthesized were subjected to a detailed molecular, thermal, structural and mechanical characterization.The results obtained, show that copolymerization leads to better mechanical response with respect to poly(lactic) acid homopolymer. Moreover, the presence of the soft block in the main polymer chain facilitates the process of biodegradability. Nanoparticles of selected copolymers fabricated by using the nanoprecipitation method showed rounded morphology and average hydrodynamic diameters around 180 nm. Cellular behavior was assessed using human fibroblasts in vitro assays and results showed absence of cytotoxicity and a good cellular adhesion and proliferation on all the copolymer surfaces.

2016 - Poly(butylene succinate)-based polyesters for biomedical applications: A review [Articolo su rivista]
Gigli, Matteo; Fabbri, Martina; Lotti, Nadia; Gamberini, Rita; Rimini, Bianca; Munari, Andrea

This contribution aims to provide an overview on the use of poly(butylene succinate) (PBS) and its copolymers in biomedicine, with particular attention to emerging topics, such as controlled drug release and tissue engineering. Indeed, PBS is a well-known aliphatic polyester, given its interesting thermo-mechanical properties and the proven biodegradability, combined with acceptable raw material and production costs. Moreover, the reactants employed in the synthesis can be obtained also from renewable resources, making PBS a fully bio-based and sustainable polymer. Although its commercialisation is mainly devoted to biodegradable packaging, the use of PBS in the biomedical field has recently attracted considerable attention. The synthetic strategies adopted and the solid-state properties, together with data on the biodegradation rate and biocompatibility of this class of polyesters are here reported and compared. Finally, the envisioned applications have been described.

2016 - Solving the group sorting problem with an AHP-based approach [Relazione in Atti di Convegno]
Lolli, Francesco; Ishizaka, Alessio; Gamberini, Rita; Rimini, Bianca

Multi-criteria decision making represents an extended branch of decision sciences which is highly applicable to several real settings. In particular, the question of ranking has attracted wide attention from researchers in the last few decades, through approaches based on different multi-criteria methods. However, ranking alternatives does not solve the question of sorting them into priority classes. When alternatives need to be classified into ordered classes, a sorting method has to be applied, but much less attention has been paid to investigating this kind of problem, especially in the case of multiple decision-makers asked to give subjective scores to different alternatives based on qualitative criteria. In this paper, a new Analytic Hierarchy Process (AHP)-based group sorting method is defined, with the aim of achieving ordered classification without asking the decision-makers to provide limiting profiles. The resulting group sorting approach is validated with a numerical example.

2016 - The waste hierarchy: A strategic, tactical and operational approach for developing countries. the case study of Mozambique [Articolo su rivista]
Ferrari, Katia; Gamberini, Rita; Rimini, Bianca

Waste management in Europe is shaped by the waste hierarchy, which guides the legislation and policy of the Member States. This hierarchy applies the following order of priority: (1) prevention; (2) preparing for reuse; (3) recycling; (4) other recovery; (5) disposal. The wide acceptance of this principle in Europe comes from a yearly developed pathway that should not be exported to other countries without consideration of the local framework. Poverty is widespread in most African countries, with the majority of the population surviving on less than 2 US dollars a day and the average waste production per capita being about half the quantity produced in Europe. However, municipal solid waste management is still inadequate throughout the region, with open waste burning and dumping being the only method of disposal in enormous cities. These in turn arise without any planning or basic infrastructure such as roads, sewers or waste landfills. We used the case study of Mozambique to define a strategic, tactical and operational approach for the implementation of the waste hierarchy and to customize it to the local situation. Like other African countries, the major weaknesses in the performance of waste management are the poor legal framework, the lack of institutional structures and the ineffective and poorly coordinated initiatives of the international stakeholders. We propose an interpretation of the waste hierarchy in order to compensate for local deficiencies and to define a local framework for the policy makers whereby prevention is no longer a priority in the short term, in order to stress the awareness and the collection. These are consolidated steps of waste management in industrialized countries but which still pose a challenge in developing nations.

2016 - Waste treatment: an environmental, economic and social analysis with a new group fuzzy PROMETHEE approach [Articolo su rivista]
Lolli, Francesco; Ishizaka, Alessio; Gamberini, Rita; Rimini, Bianca; Ferrari, Anna Maria; Marinelli, Simona; Savazza, Roberto

Most complex decisions involve several stakeholders and therefore need to be solved using a group multi-criteria decision method. However, stakeholders or decision-makers often have divergent views, especially in the environmental sector. In order to integrate this divergence, a new group fuzzy PROMETHEE approach is introduced to combine the traditional environmental criteria of life cycle assessments with social and economic criteria. The modelling of uncertainty within the group of decision-makers using a fuzzy approach makes this method unique. The proposed fuzzy approach differs significantly from the standard one. The decision-makers express their judgments in crisp forms. In order to take into account the intrinsic dispersion of judgments within the group, a posteriori fuzzification procedure is applied. The crisp values are not simply aggregated; they are converted into a triangular fuzzy number based on the given evaluations. As a consequence, the definition of fuzzy membership functions, as required in standard fuzzy logic, is not required, which simplifies the process and makes it more reliable. The new approach is illustrated with a real case study concerning the selection of the best waste treatment solution in a natural park from among a traditional incinerator and an innovative integrated plant.

2015 - A bi-objective heuristic for supporting fire stations to respond quickly and efficiently in case of micro calamities [Articolo su rivista]
Lolli, Francesco; Pergreffi, A.; Gamberini, Rita; Rimini, Bianca; Regattieri, A.

Among the wide set of requests of interventions sent to a fire station, the so called ‘micro calamities’ may play a significant role. They are characterized by simultaneous requests of low severity mark from a spread area. These events are completely comparable to those referring to the post-crisis humanitarian logistics. A pure cost-based approach does not fit with this operative issue, as well as a pure minimum latency approach, which is typically applied in the previous acute phases. Thereby, a bi-objective problem is formulated and solved by means of an ‘a priori’ scalarization heuristic. A case study shows the applicability of the proposed approach and indicates the opportunity of further investigations.

2015 - An innovative method to optimize the maintenance policies in an aircraft: general framework and case study [Articolo su rivista]
Regattieri, A.; Giazzi, A.; Gamberi, M.; Gamberini, Rita

Maintenance policies applied to aircrafts are governed by a mix of airworthiness authorities’ regulations and choices of suppliers and users. This allows airlines to use different strategies to minimize the total costs of maintenance. In this paper, a new approach that integrates the failure and reparation processes, such as modelling, optimization algorithms, and simulation methods, is proposed to define the best maintenance strategies for complex systems. A case study of an airline carrier is presented. In particular, several critical components for the A320 aircraft family are considered. The impact of the spare parts inventory management is discussed. Different preventive maintenance policies are tested and simulated. With the new policies, the average availability of the aircraft is satisfactory and the total annual cost is reduced to a value of approximately 20% in comparison with the previous policies adopted by the company.

2015 - FlowSort-GDSS - A novel group multi-criteria decision support system for sorting problems with application to FMEA [Articolo su rivista]
Lolli, Francesco; Ishizaka, Alessio; Gamberini, Rita; Rimini, Bianca; Messori, Michael

Failure mode and effects analysis (FMEA) is a well-known approach for correlating the failure modes of a system to their effects, with the objective of assessing their criticality. The criticality of a failure mode is traditionally established by its risk priority number (RPN), which is the product of the scores assigned to the three risk factors, which are likeness of occurrence, the chance of being undetected and the severity of the effects. Taking a simple "unweighted" product has major shortcomings. One of them is to provide just a number, which does not sort failures modes into priority classes. Moreover, to make the decision more robust, the FMEA is better tackled by multiple decision-makers. Unfortunately, the literature lacks group decision support systems (GDSS) for sorting failures in the field of the FMEA. In this paper, a novel multi-criteria decision making (MCDM) method named FlowSort-GDSS is proposed to sort the failure modes into priority classes by involving multiple decision-makers. The essence of this method lies in the pair-wise comparison between the failure modes and the reference profiles established by the decision-makers on the risk factors. Finally a case study is presented to illustrate the advantages of this new robust method in sorting failures.

2015 - Retrofitting of R404a commercial refrigeration systems using R410a and R407f refrigerants [Articolo su rivista]
Bortolini, Marco; Gamberi, Mauro; Gamberini, Rita; Graziani, Alessandro; Lolli, Francesco; Regattieri, Alberto

This paper presents an experimental analysis about the retrofitting of two commercial stationary refrigeration systems marketed by an Italian leading company. Such systems operate both at medium temperature (MT), i.e. [-5; 10]°C, and low temperature (LT), i.e. [-25; -15]°C, and they are originally designed to work with hydrofluorocarbon (HFC) R404a, known as a high global warming potential (GWP) fluid (GWP = 3922). The goal is to investigate the performances of HFC R410a (GWP = 2088) and R407f (GWP = 1825), chosen as effective alternatives to HFC R404a. Such fluids are compatible with the refrigeration systems, non-flammable and easy-available. Furthermore, they meet the European Union (EU) restrictions in force in the next future, so that they are suitable to start the transition toward efficient and eco-friendly refrigeration systems. The experimental campaign shows the feasibility of adopting R407f and R410a for the MT refrigeration system and R407f fluid for the system operating at LT.

2015 - The effect of plasma surface modification on the biodegradation rate and biocompatibility of a poly(butylene succinate)-based copolymer [Articolo su rivista]
Fabbri, Martina; Gigli, Matteo; Costa, Michela; Govoni, Marco; Seri, Paolo; Lotti, Nadia; Giordano, Emanuele; Munari, Andrea; Gamberini, Rita; Rimini, Bianca; Neretti, Gabriele; Cristofolini, Andrea; Borghi, Carlo A.

In this contribution, a poly(butylene succinate)-based copolymer containing thioether linkages (P(BS85BTDG15)) has been synthesized and characterized from the molecular, thermal and mechanical point of view. The results have been compared to the parent homopolymer. Films obtained both by PBS and P(BS85BTDG15) have been subjected to surface modification by means of non-thermal plasma surface treatment and the effect on physic/mechanical properties has been considered. Hydrolytic degradation rate under physiological conditions and in vitro biocompatibility of treated and non-treated polymeric films have been also investigated. The introduction of thioether linkages and the plasma etching enhanced the polymer surface wettability, thus resulting in an increased hydrolytic degradation rate. On the other hand, bulk properties were not significantly affected. Biocompatibility assays highlighted the absence of potentially cytotoxic products into the culture medium and proved that the investigated polymeric films can support cell adhesion and proliferation.

Lolli, Francesco; Gamberini, Rita; Regattieri, A.; Rimini, Bianca

Managing intermittent demand represents a very critical task in term of forecasting and stock control due to the variability both of demand sizes and demand arrivals. In this pa-per the forecasting issue is tackled by comparing different extrapolative forecasting ap-proaches. In particular, the SARIMA model (Seasonal Autoregressive Integrated Moving Average) is applied on 60 real time series by means of the TRAMO-SEATS procedure, which is a versatile and automatic procedure allowing a quick identification of the best performing SARIMA model for each item. The forecasting performances are then compared with those obtained by the well-known methods of Croston and Syntetos-Boylan, which represent two modified versions of the simple exponential smoothing specifically introduced for estimating the mean demand per period in case of intermittent demand profiles. Furthermore, the aggre-gation of forecasts in lower-frequency ‘time buckets’ is implemented in order to evaluate how these methods behave on aggregated time horizons.

Ferrari, Anna Maria; Spinelli, Rosangela; Gamberini, Rita; Neri, P.; Pini, Martina; Rimini, Bianca

The mission of sustainable development exerted the pressure demanding for the adoption of proper methods to protect the environment across all industries, including construction. Waste management is considered an urgent problem that needs to be addressed by identifying favorable solutions to minimize its environmental burden. Recycling is one of the strategies inducing the minimization of waste directed to landfill sites, by promoting their reuse, along with reducing demand for new raw materials. In the construction field, the request of aggregates generates a strong impact on the territory because of a mining activity, which can be planned and regulated with great difficulty. It is more and more relevant to focus on the qualitative and quantitative evaluation of contribution that the secondary aggregates, obtained by valorization of waste, can lead to the fulfillment of the needs of the construction industry. For this reason it is necessary to assess, in terms of a technical and environmental point of view, the industrial processes to obtain the secondary raw materials available for use and to compare them with the production of natural aggregates by mining activity. This paper aims to compare the environmental impact due to the production of adhesive for the laying of baked clay, obtained by the manufacturing of baked waste and natural aggregates, by paying attention on the main environmental burdens which characterize the production of natural and recycled aggregates. As a result, the recycling process leads to an increase in environmental impact compared to the production of natural sand as the energy consumption in the recycling process reduces the benefits of saving raw materials. However, the ceramic waste recycling leads to a decrease of the overall potential damage of 44% compared to landfilling.

Gamberini, Rita; Galloni, Luca; Rimini, Bianca

La Direttiva europea 2008/98/CE rappresenta il riferimento per la definizione di misure volte a proteggere l’ambiente e la salute umana prevenendo o riducendo gli impatti negativi della produzione e della gestione dei rifiuti e limitando gli impatti complessivi dell’uso delle risorse. La sua emanazione è preceduta da un ampio confronto all’interno della Comunità Europea (CE), le cui tracce sono evidenti: - nella decisione n. 1600/2002/CE che istituisce il Sesto programma comunitario di azione in materia di ambiente e sollecita l’estensione o la revisione della normativa in vigore, in particolare al fine di chiarire la distinzione tra ciò che è rifiuto e ciò che non lo è, nonchè di promuovere lo sviluppo di misure in materia di prevenzione e gestione dei rifiuti, compresa la definizione di obiettivi. Peraltro, la necessità di fornire una definizione di “rifiuto” è ribadita nella comunicazione del 27 Maggio 2003 e nella successiva risoluzione del 20 Aprile 2004 - nella direttiva 2000/53/CE che contribuisce a diffondere principi quali “chi inquina paga”, nonchè la necessità di una fase di progettazione dei prodotti in vista del loro riciclaggio e recupero e il conseguente perseguimento di obiettivi prefissati in termini di reimpiego, riciclaggio e recupero dei rifiuti - nella direttiva 2002/96/CE (ora recente-mente aggiornata dalla direttiva 2012/19/UE), che applica i summenzionati concetti al settore dei RAEE, cioè dei Rifiuti di Apparecchiature Elettriche ed Elettroniche. In tale ambito, si sviluppa nella direttiva 2008/98/CE una forte attenzione a una fase innovativa nella gestione dei rifiuti: la preparazione al riutilizzo, intendendo con tale termine le operazioni di controllo, pulizia e riparazione attraverso cui prodotti o componenti di prodotti diventati rifiuti sono preparati in modo da poter essere reimpiegati senza altro pretrattamento. Particolarmente adatti a questa tipologia di trattamento sono i rifiuti ingombranti, i rifiuti di apparecchiature elettriche ed elettroniche, gli abiti usati. Nel proseguo, l’attenzione sarà rivolta ai rifiuti di apparecchiature elettriche ed elettroniche, per i quali sono già attive sul territorio europeo imprese appartenenti a reti per la preparazione al riutilizzo e per i quali diventa cruciale il tema della previsione della vita utile e conseguentemente della definizione della più opportuna politica di revisione e di sostituzione dei componenti. Nasce così una nuova sfida e un nuovo ambito di applicazione per la teoria della affidabilità e per le competenze ad essa connesse, inclusa la capacità di definizione di standard consolidati. Cruciale è inoltre la loro integrazione con le metodologie per l’analisi del ciclo di vita dei prodotti. Nei paragrafi successivi, quindi, sarà presentata la recente specifica tecnica PAS 141:2011, definita nel Regno Unito per regolamentare la preparazione al riutilizzo di apparecchiature elettriche ed elettroniche, per arrivare poi a concentrarsi su recenti modelli per valutare la vita utile residua di apparecchiature elettriche ed elettroniche usate.

Gamberini, Rita; Lolli, Francesco; Regattieri, A.; Rimini, Bianca

Irregular and sporadic demand profiles frequently occur in different contexts characterised either by a large fragmentation of client requests within a broad product mix or when new products are introduced. Their optimal management often requires the definition of approaches based on Key Performance Indicators (KPI) other than costs, which in the aforementioned situations are characterised by uncertainty. Specifically, holding costs and stock-out costs are difficult to quantify. This paper examines 104 dynamic re-order policies in an environment where demand patterns with very low demand frequency and demand size equal to very few items are required by customers. Furthermore, the cost structure is uncertain. The aforementioned alternative management approaches are experimentally compared in terms of the average inventory level, average and maximum lost demand and average number of stock-out they can ensure.

Fabbri, Martina; Gigli, M.; Gamberini, Rita; Lotti, N.; Gazzano, M.; Rimini, Bianca; Munari, A.

In this contribution a new class of aliphatic poly(butylene succinate) (PBS)-based poly(ester urethane)s has been synthesized and characterized from the molecular, thermal and mechanical point of view. Hydrolytic degradation studies under physiological conditions have been conducted to assess their biodegradation rate. To obtain copolymers showing both thermoplastic and elastomeric properties, the chain-linking strategy has been considered. In particular, two hydroxyl-terminated oligomers have been synthesized by melt polycondensation: poly(butylene succinate) (PBS), as a "hard segment", and two poly(butylene adipate/diglycolate) P(BAmBDGn) random copolymers as a "soft segment". The introduction of ether-linkages along the PBA chain permitted to depress its crystallinity degree and to enhance the wettability. Multiblock copolymers were finally obtained by chain extending with hexamethylene diisocyanate each P(BAmBDGn) copolymer with two different mass percentages of PBS: 30% and 50%. All copolymers maintained good thermal stability and were characterized by melting temperatures above 100 °C. Elastic modulus (E) and stress at break (σb) varied with the chemical composition: the higher the PBS amount, the higher E and σb. No yield and very high elongations at break were observed. Hydrolytic degradation studies highlighted an increase of the degradation rate with the increase of the BDG content.

Gamberini, Rita; Castagnetti, E.; Lolli, Francesco; Rimini, Bianca

In this paper the problem of allocating and scheduling jobs on parallel unrelated machines is studied. Jobs are grouped in families of similar items. A sequence dependent setup is required between batches of jobs belonging to the same and different families, even if in the first case lower time is required. The size of batches is not known a-priori, hence the problem is divided in two different sub-problems: a) the allocation of volumes of work on each machine and b) subsequently the scheduling of each item. The focus of the paper is on the first step and consequently on the pre-assignment problem. Three different solving approaches are implemented in several real-life case studies.

Pini, Martina; Ferrari, Anna Maria; Gamberini, Rita; Neri, P.; Rimini, Bianca

Purpose Ceramic tiles play a strategic role in the Italian market; currently, the Italian production is of 367.2 million m2 (Confindustria Ceramica 2012). In 2009, Italy was positioned as the world’s fourth largest producer of ceramic tiles, producing 368 million m2 of the world’s total production of 1,735 million m2 Giacomini (Ceram World Rev 88:52–68, 2010). Therefore, there is an ongoing effort to create innovations in the products offered and their manufacturing processes, in order to better compete on the market and to create eco-friendly products. Recently, the Italian Ceramic District has increased its focus on environmental issues with the aim of protecting natural resources and reducing the energy and material consumption. For this reason, a new product was born in the Italian Ceramic District, namely, a large thin ceramic tile (dimensions 1,000 mm × 3,000 mm × 3.5 mm) reinforced with a fibreglass backing, which gives the product excellent resistance and flexibility properties. The aim was to manufacture a new product with lower environmental impact than the traditional one. The production of a large thin ceramic tile requires, in fact, a lower quantity of materials, transports and energy consumptions comparing to the same metres square of traditional ceramic tile. At the present, no comparative life cycle assessment (LCA) studies have been performed between traditional and innovative ceramic stoneware tiles. This study analyses, for the first time, a life cycle of the innovative ceramic product (porcelain stoneware) developed by a company of the Italian Ceramic District. Methods The analysis is performed using the LCA methodology, in order to identify environmental impacts, energy consumption and CO2 equivalent emissions that occur during extraction of raw materials, transportation, production, material handling, distribution and end-of-life stages within a cradle to grave perspective. Results and conclusions LCA analysis indicates that the highest environmental impact mainly affects the respiratory inorganics impact category due to base slip production (27.62 %), caused by the transport of the raw materials and by non-renewable impact category due to both the pasting phase (21.31 %) and the two-component adhesive manufacture. The major greenhouse gas (GHG) emissions are related to the production of polyurethane, a component of the adhesive used in the pasting stage, and to the natural gas consumption in the firing process.

Lolli, Francesco; Ishizaka, A.; Gamberini, Rita

Multi-Criteria Inventory Classification (MCIC) groups inventory items with respect to several criteria, in order to facilitate their management. This paper introduces a new hybrid method based on AHP and the K-means algorithm. On benchmarking data, it provides a clearly higher clustering validity index than previous sorting methods. However, as with previous methods, it is a full compensatory method. This means that an item scoring badly on one or more key criteria may still be placed in the best class because these bad scores are compensated. In order to prevent these hidden bad scores, a new variant method is introduced: AHP-K-Veto. The sorting is performed on each single criterion, where a veto system prevents an item evaluated as high/bad on at least one criterion to be top/bottom ranked in the global aggregation. This veto system is an assurance against hidden problems but slightly worsens the clustering validity index.

Lolli, Francesco; Gamberini, Rita; Regattieri, A.; Rimini, Bianca; Morsiani, M.

The liaison between forecasting and inventory control represents a promising research field even if they have been often considered as independent problems. Otherwise, this paper follows a recent set of works that proved the importance of simultaneously considering both aspects. As a consequence, the choice of the best-performing approach should not consider only the accuracy of forecasts, but also the effects of forecasting methods on re-order policies. In particular, this paper deals with different periodic inventory control methodologies, with different lead times and safety stocks. The application to intermittent demand patterns is studied. The best Seasonal Autoregressive Integrated Moving Average (SARIMA) forecasting models are initially automatically identified by the TRAMO-SEATS software and results obtained are subsequently used for tuning periodic review inventory control approaches. The experimental analysis is performed on a real data set of 40 time series. A discrete-event simulation finally shows the obtained effects. Two features of this paper are remarkable. The former is that the intermittent data set is not pseudo-random generated and thus assumptions on the best-fitting demand distribution are not required. The latter regards the full automation of the TRAMO-SEATS software, which indicates its ability of being applied also in real industrial environments.

Gamberini, Rita; Galloni, Luca; Rimini, Bianca; Luppi, M.

The European Directive 2008/98/EC on Waste provides guidelines for ensuring sustainable waste management. Specifically, a hierarchy for ranking the available management options is established. Highest priority is given to waste prevention, followed by re-use and, only after that, recycling and recovery of materials, energy recovery through incineration and finally, disposal in landfills. However, even the second highest priority, reuse, is often overlooked in favor of recycling, given the existence of well-established technologies. In this paper, re-use of post-consumer textile waste is studied, by specifying the main steps supporting such a sustainable process and by outlining the magnitude of the expected impact. Finally, a case study is presented.

2014 - Progetto di restauro dell’ex sinagoga di Ostiano (CR): verso una valutazione di sostenibilità [Poster]
Marinelli, Simona; Ferrari, Anna Maria; Gamberini, Rita; Maramotti, Anna; Neri, Paolo; Riccardi, Maria Pia; Settembre Blundo, Davide; Rimini, Bianca

Ostiano, comune in provincia di Cremona, ospitò fino agli anni Trenta una numerosa comunità israelitica, erede di una migrazione risalente al XV secolo. La Sinagoga è sita all’interno del complesso castellano (Fig. 1) del paese, a due passi dal Teatro Gonzaga. Varcato l’antico ingresso si è come attirati dalla grande casa che sorge sul lato di sinistra. La costruzione, nonostante il pessimo stato conservativo, mostra ancora nobiltà di forme. Venne edificata all’inizio del Cinquecento come dimora del rappresentante del potere gonzaghesco, poi rimase ad uso del governatore sino al 1619 quando Francesco Gonzaga, marchese di Ostiano e Vescovo di Mantova, la donava in parti uguali alla parrocchia e al convento francescano dei Santi Gaudenzio e Alessadro. Perduta la sua funzione di residenza, nel 1731 i due enti proprietari la cedevano alla fiorente comunità ebraica locale. Una volta ottenuto l’uso della casa la comunità israelitica iniziò una vasta opera di ristrutturazione. L’edificio venne modificato radicalmente, sopraelevato per creare il matroneo ad uso cultuale: nasceva così la sinagoga. All’epoca della fondazione risalgono gli ambienti del piano terra, composti da due sontuosi saloni e altri vani, tutti ambienti decorati con armoniosi soffitti a volta o a ombrello. Si tratta di ampi spazi, circa 700 mq su tre piani; la sinagoga sorgeva nel sopralzo. L’elegante facciata presenta due balconi.L’analisi del ciclo di vita del restauro del caso oggetto di studio sarà effettuata considerando i materiali che costituiscono l’involucro e le partizioni interne, dall’estrazione delle materie prime, alla produzione dei manufatti, all’assemblaggio in cantiere sino allo scenario di fine vita. Saranno inclusi tutti i trasporti dai vari impianti produttivi sino al cantiere e allo smaltimento finale e saranno incluse tutte le energie impiegate sia per la messa in opera nella fase di cantiere, sia per la fase d’uso dell’intero edificio (riscaldamento e condizionamento, ventilazione forzata, illuminazione artificiale, uso delle utenze) per un tempo di vita utile stimato dell’edificio restaurato pari a 100 anni. Il Metodo di valutazione d’impatto utilizzato sarà IMPACT 2002 + modificato con indicatori culturali ed economici per garantire una maggiore rappresentatività del sistema studiato e al fine di considerare i vantaggi che possono provenire dal restauro e dalla valorizzazione di un edificio storico.

Regattieri, A.; Santarelli, G.; Gamberi, M.; Gamberini, Rita

This paper focuses on the analysis of the internal flow traceability of goods (products and/or packages) along the supply chain by Radio Frequency IDentification (RFID) technology. Traditionally, the traceability system is performed through the asynchronous fulfilment of checkpoints (i.e. doorways) by materials. In such cases, the tracking is manual, executed by operators that manually trace the path. Often companies are not aware of the inefficiencies due to these traceability systems such as low precision and accuracy in measurements (i.e. no information between doorways), more time spent by operators and costs (due to the full effort of operators who have to search for the good positions and movements). In order to overcome these limitations, automatic identification procedures have been introduced in many service industries, purchasing and distribution logistics, manufacturing companies and material flow systems. Automatic identification procedures can also be applied to the packaging of products, instead of to each item contained in the package. Sometimes products are very expensive and packages contain important and critical goods (for example dangerous or explosive materials), thus the tracking of goods – and packages in particular – is a critical function. In order to analyse the traceability of the packaging system, the authors have developed an innovative system based on RFID-UWB technology. A prototype of this system has been realised and used for an experimental research that has consisted of several tests (static and dynamic), tracing the position (static) and movements (dynamic) of products and in particular packages in indoor environments, in continuous and in real time.

Gamberini, Rita; Meli, M.; Galloni, Luca; Rimini, Bianca; Lolli, Francesco

Assembly lines managed by means of lean production philosophy are usually characterized by workstations with inline stock areas, supplied by means of items contained in a larger supermarket zone. Furthermore, inline components necessities are usually showed by means of the use of kanbans. In this work, the number of kanbans and the number of carriers serving the line are computed by means of Erlang-C approach, in order to minimize a total cost function obtained as the sum of an estimation of cost of inline stock and of cost of refilling operations. Specifically, the Erlang-C approach is adopted since assures fast re-design of the system when variations in input data occur. Finally, a real-life case study in a company manufacturing items for the automotive market field is presented in order to highlight the approach potentialities when alternative scenarios are studied.

Piccinini, P.; Gamberini, Rita; Prati, A.; Rimini, Bianca; Cucchiara, Rita

The costs associated with the management of healthcare systems have been subject to continuous scrutiny for some time now, with a view to reducing them without affecting the quality as perceived by final users. A number of different solutions have arisen based on centralisation of healthcare services and investments in Information Technology (IT). One such example is centralised management of pharmaceuticals among a group of hospitals which is then incorporated into the different steps of the automation supply chain. This paper focuses on a new picking workstation available for insertion in automated pharmaceutical distribution centres and which is capable of replacing manual workstations and bringing about improvements in working time. The workstation described uses a sophisticated computer vision algorithm to allow picking of very diverse and complex objects randomly available on a belt or in bins. The algorithm exploits state-of-the-art feature descriptors for an approach that is robust against occlusions and distracting objects, and invariant to scale, rotation or illumination changes. Finally, the performance of the designed picking workstation is tested in a large experimentation focused on the management of pharmaceutical items.

Rimini, Bianca; Gamberini, Rita; Bianchi, M.; Lolli, Francesco

La progressiva diffusione delle logiche di gestione delle singole aziende o delle supply chain basate sui principi del Total Quality Management e del Lean Thinking hanno portato ad un cambio di prospettiva, non più focalizzato sul prodotto, ma sulla customer satisfaction e sulle caratteristiche dei processi (interni o esterni all’impresa, di stampo produttivo o organizzativo o legato alla gestione di servizi per il cliente) che permettono di perseguirla. Tale cambiamento è evidente anche analizzando le novità imposte dalla normativa UNI EN ISO 9001: 2000 e dai suoi successivi aggiornamenti. Obiettivo quindi di ogni sistema produttivo diventa la proposta sul mercato di prodotti e servizi con requisiti di qualità tali da soddisfare clienti sempre più esigenti. Risultato questo perseguibile solo con un forte orientamento ad esso di tutte le componenti aziendali e con un significativo monitoraggio delle componenti di costo legate alla non completa soddisfazione dei requisiti di qualità. Tali componenti di costo nel seguito verranno sinteticamente denominate Non-Conformity-Costs (NCCs). Il framework di riferimento per lo studio è la normativa ISO 10014:2006 Quality management – Guidelines for realizing financial and economic benefits e la pubblicazione proposta da Feigenbaum nel 1991, che suddivide NCCs mediante il modello PAF – Prevention Appraisal Failure, cioè in base alla loro pertinenza con azioni di prevenzione, controllo o conseguenti alla gestione di un guasto (o più in generale di un difetto). Il presente lavoro descrive i risultati conseguenti al monitoraggio dei NCCs all’interno della supply chain di una azienda manifatturiera operante sul territorio nazionale ed internazionale e l’effetto di una corretta formazione degli operatori coinvolti nel processo, al fine di ridurre la frequenza di presentazione dei guasti e dei difetti.

Marinelli, Simona; Gamberini, Rita; Rimini, Bianca; Ferrari, Anna Maria; Neri, P.; Montorsi, Luca; Milani, Massimo

L'obiettivo dello studio è la valutazione di impatto ambientale di porzioni incrementali di raccolta differenziata, provenienti dal circuito dei Rifiuti Solidi Urbani (RSU) prodotti all'interno di aree dedicate a parco naturale. Mediante l'approccio LCA (LIfe Cycle Assessment) sono stati confrontati diversi sistemi di gestione e trattamento. Si è comparata la tradizionale gestione mediante incenermento con i risultati ottenuti da un innovativo sistema integrato, in grado di fornire energia. I primi risultati dimostrano che l'impatto ambientale è migliorato e che esso diminuisce in maniera considerevole all'aumentare dell'ammontare di rifiuti differenziati trattati.

Fabbri, Martina; Gamberini, Rita; Gigli, M.; Lotti, N.; Rimini, Bianca

The development of an eco-friendly item implies the design of a sustainable material. Such a liaison is crucial in the biomedical field, where disposable devices are used in a broad range of applications, i.e. blisters, sutures, implants, scaffolds for tissue engineering and controlled drug delivery systems. As a consequence, the choice of biodegradable and healthy solutions, given their contact with human body, is a fundamental pre-requisite. In this view, this paper compares a set of noteworthy existing PBS-based biodegradable polyesters in order to summarize their main properties and support designers during the material selection step, by following a life cycle thinking perspective.

2013 - Comparative life cycle assessment of traditional and innovative ceramic stoneware tiles [Abstract in Atti di Convegno]
Pini, Martina; Gamberini, Rita; Rimini, Bianca; Neri, Paolo; Ferrari, Anna Maria

Ceramic tiles are widely used as building materials. It has been estimated that the contribution of all types of ceramic materials included in a building constitute about the 50% of the whole used materials. Recently, in the Sassuolo Ceramic District has increased the attention toward the environmental issues with the aim of protecting natural resources and of reducing energy and material consumptions. This issue results in the production of an innovative ceramic stoneware slab with only 3.5 mm of thickness reinforced with a fiberglass blanket. The aim of the present study is to compare the environmental impact of a traditional ceramic stoneware tile with a thin reinforced ceramic stoneware tile. The functional units chosen for this study is 1 m2 for both the traditional porcelainized stoneware tile and the innovative ones. The LCA study has been performed using the SimaPro 7.3.3 software and IMPACT 2002+ impact assessement method. The system boundaries for the analysis include the upstream and downstream phases, from raw material extraction to the end of life of the product, thus obtaining “a cradle to grave” overview. The analysis of the results shows that the traditional porcelainized stoneware tile determinates a major impact (11.88 mPt) than the innovative ceramic stoneware tile (7.469 mPt), in particular the total damage decreases of 37.13%. The damage assessment indicates: • a decrease of 50.16% in Human Health category thanks to the reduction of NOx emissions (-36.37%) generated by transports of raw materials, • a reduction of 28.85% in Resources category thanks to the saving of natural gas consumption (-10%) in the firing phase, • a decrease of 22.42% in Climate Change category caused by the CO2 emissions reduction (-23.33%) in the firing process, • a reduction of 52.52% in Ecosystem Quality category thanks to the Zinc emissions reduction (-54.9%) generated by the transports. In conclusion the innovative ceramic stoneware tile allows to save energy consumptions, to reduce the raw materials and to decrease the transports compared to the traditional system.

Gamberini, Rita; Rimini, Bianca; Nicandri, P.

Thousands of tonnes of Municipal Solid Waste (MSW) are produced every day, and consignment to landfill represents the most common disposal choice. However, sanitary problems and the increasing demand for dedicated spaces have directed the efforts of researchers and practitioners towards the study of alternative approaches to waste management. Composting is one possible way to treat the organic portion of MSW, and the efficient design and management of composting plants ensure that they are economically sustainable. Analyzing established or pioneering solutions allows guidelines to be drawn up for the design of new plants and/or the management of existing ones. In this paper, a set of engineering indices for the technical and economic analysis of composting plants is first presented and then applied to data collected from 10 existing plants, divided into two subgroups: plants mainly composting the organic fraction of household solid waste, with reduced levels of the organic fraction of agro-industrial waste, green waste and sludge (named Group A), and plants only composting green waste (named Group B). For Group A plants, more complex technological solutions are required, given the need to manage larger portions of untreated waste and leachate, along with odor problems. This means that the need for space (particularly covered space), facilities, operators, and initial investment is greater and annual operating costs are higher. However, Group A plants can also charge more for processing waste.

Marinelli, Simona; Gamberini, Rita; Rimini, Bianca; Ferrari, Anna Maria; Neri, P.; Milani, Massimo; Montorsi, Luca

All’interno del progetto RELS è stata valutata l’applicabilità di un impianto integrato che accoppia un processo di digestione anaerobica e di gassificazione, unitamente a un processo per il recupero delle acque reflue in modo da valorizzare energeticamente la frazione organica dei rifiuti solidi urbani, così come la parte non riciclabile della raccolta differenziata. L’energia elettrica prodotta viene immessa in rete, mentre la parte di energia termica rimanente rispetto ai bisogni interni dell’impianto stesso può essere messa a disposizione in funzione delle necessità del territorio. La presenza come partner del Parco delle Foreste Casentinesi ha permesso di raccogliere informazioni e dati sulla raccolta di rifiuti nell’area del parco e nei comuni che afferiscono al parco stesso. Nel progetto RELS sono stati analizzati diversi scenari e configurazioni d’impianto in modo da identificare quale soluzione progettuale meglio si adatta alle esigenze del territorio.

2013 - Life Cycle Assessment of a nanoTiO2 glazed steel panel [Relazione in Atti di Convegno]
Marinelli, Simona; Gamberini, Rita; Neri, Paolo; Pini, Martina; Rimini, Bianca; Ferrari, Anna Maria

Titanium dioxide is one of the most important and common photocatalyst because of its outstanding efficiency (even under weak solar irradiation), compatibility with a large number of materials and good stability. With the development of TiO2 nanomaterials, its uses ranges over a variety of fields such as functional coating photoelectrolysis, photocatalysis, dye sensitized solar cells, gas sensor, optical fibers, electrochromic material for display devices, biomedical fields, etcThe present study concerns the ecodesign of industrial scale up of nanoTiO2 glazed steel panel production performed by LCA (Life Cycle Assessment) methodology. The functional unit chosen for this study is 1 m2 of steel panel (size 1000 mm x 1000 mm x 1 mm) on which is applied glaze funzionalized with TiO2 nanoparticles. The system boundaries of the entire life-cycle include production, distribution/installation, use and end of life phases, thus obtaining “a cradle to the grave” overview. The LCA study has been performed using the SimaPro7.3.3 software and IMPACT 2002+ impact assessment method. The phase of the life cycle with the highest environmental impact is the production (34.42% of the total damage) due to Nitrogen oxides (28.82%) and Particulates < 2.5m (21.16%) air emissions. In particular, the application of white funzionalized glaze step has the higher environmental load (74.2% of the production damage), followed by the grund application step (20.78%) and by the production of the white glaze through a wet grinding of frits mixture and nanoTiO2 solution with alumina balls (3.65%). Regarding the others life cycle phases, the impact of usage step (27.43% of the total damage) is caused by CO2 emissions (52.05%) and the end of life step (13.09% of the total damage) affects with Nitrogen oxide and Particulates, <100nm (indoor) air emissions

Gamberini, Rita; DEL BUONO, D.; Lolli, Francesco; Rimini, Bianca

The definition and utilisation of engineering indexes in the field of Municipal Solid Waste Management (MSWM) is an issue of interest for technicians and scientists, which is widely discussed in literature. Specifically, the availability of consolidated engineering indexes is useful when new waste collection services are designed, along with when their performance is evaluated after a warm-up period. However, most published works in the field of MSWM complete their study with an analysis of isolated case studies. Conversely, decision makers require tools for information collection and exchange in order to trace the trends of these engineering indexes in large experiments. In this paper, common engineering indexes are presented and their values analysed in virtuous Italian communities, with the aim of contributing to the creation of a useful database whose data could be used during experiments, by indicating examples of MSWM demand profiles and the costs required to manage them.

Gamberini, Rita; Consoli, D.; Lolli, Francesco; Rimini, Bianca

For ceramic tile manufacturers, warehouse management represents an extremely critical issue due to the necessity of storing pallets in an open yard by stacking them according to specific storage rules. In particular, pallets belonging to the same production batch must be stored in adjacent bins because customer orders must be collected from the same batch. Hence, a high fragmentation of the yard must be avoided. In order to free the bins that are to be assigned to the batches, shuffling operations must be performed before the batches are delivered by the production lines. In this paper, a shuffling algorithm is presented with the aim of designing a useful and flexible tool that may be integrated into a Warehouse Management System.

Gamberini, Rita; Galloni, Luca; Rimini, Bianca

The Overall Equipment Effectiveness (OEE) is a useful tool for evaluating the time that manufacturing resources spend on adding value operations and for idle or waste time, whose elimination or at least whose reduction is progressively recommended. In this paper, four alternative approaches for OEE evaluation are reviewed and commented on in order to guide practitioners in the choice preceding their adoption. Specifically, in accordance with data required for the computation and results assured by the implementation, a preferable operating field is suggested.

Pini, Martina; Ferrari, Anna Maria; Gamberini, Rita; Iannotti, Mario; Rimini, Bianca

L’obiettivo dello studio è la valutazione comparativa del danno ambientale dovuto al ciclo di vita dei processi di macinazione a secco e a umido di impasti ceramici per la produzione del grès porcellanato prodotto in Egitto. L’analisi ha evidenziato come la tecnologia di macinazione a secco comporti una riduzione del danno ambientale del 25% rispetto alla macinazione a umido principalmente a causa dell’utilizzo del deflocculante.

Gamberini, Rita; Rimini, Bianca; Dell'Amico, Mauro; Lolli, Francesco; Bianchi, M.

Order picking related costs may account for up to 65% of the total expense of warehouse management. Hence, the implementation of robust design and optimization procedures for planning picking is addressed by researchers and practitioners.In this chapter the case of warehouses served by humans, in picker-to-parts systems, with a discrete picking organization is studied. Specifically, the case of orders including multiple different items, located in different aisles and requiring more than one forklift load to completely satisfy customer requests is analyzed, with the aim of minimizing the time for retrieving an order. Specifically, two aspects are studied:•the grouping of orders into a finite number of forklift missions, by assuring that each required item is picked in the required amount•the optimization of the routing to be followed by handling facilities in accordance with the objective of minimizing the total travelled distance and the computation of the number of handling facilities necessary for serving the warehouse aisles.

Gamberini, Rita; Galloni, Luca; Rimini, Bianca

La crescente attenzione verso le tematiche ambientali e la sicurezza degli operatori hanno portato recentemente le aziende a focalizzare la loro attenzione all’uso più efficace degli impianti di produzione e alla prevenzione dei guasti. Alla politica di gestione della ma-nutenzione "a guasto", cioè alla realizzazione degli interventi di manutenzione solo in se-guito a momenti di fermo, fa seguito lo svi-luppo di politiche di manutenzione preventiva, lo sviluppo di approcci di gestione degli interventi basati sulla analisi statistica del comportamento degli impianti, al fine di pre-vederne il malfunzionamento e quindi di anti-cipare le attività di manutenzione in periodi di fermo già schedulati. La manutenzione preventiva, tuttavia, richiede risorse per essere implementata in maniera efficiente, a causa della mole di dati necessa-ria per avere una affidabile previsione dei modi e dei tempi di guasto e per la loro suc-cessiva elaborazione. Ne consegue che stru-menti atti a selezionare gli interventi a mag-giore impatto sull'efficienza complessiva del sistema in analisi risultano particolarmente interessanti e attrattivi. Uno strumento a disposizione dei decision makers è l'indice OEE - Overall Equipment Effectiveness, fortemente influenzato dalle politiche di manutenzione preventiva implementabili in azienda. Tale legame costituisce il focus del paper.

Gamberini, Rita; Bicchierini, E.; Lolli, Francesco; Rimini, Bianca; Regattieri, A.; Galloni, Luca

The Assembly Line Balancing Problem (ALBP) consists in assigning tasks to operators engaged on a line in such a way that the final item is produced according to a pre-determined production rate and by optimizing pre-defined objective functions. In the literature, a wide range of algorithms claiming to solve ALBP are found, however almost all of them consider this problem from a mathematical standpoint, thus disregarding details which are useful for ensuring the correct implementation of proposed solutions in real-life environments. Authors have gradually narrowed the gap between theory and practice by introducing stochastic operating times when manual operations are executed, or by describing more and more complex versions of the problem, usually known by the term GALBP (Generalized Assembly Line Balancing Problem), where a wide variety of objective functions and constraints are managed. By researching such an area, this paper will investigate the case of redesigning a manufacturing area dedicated to the production of heavy and voluminous items by highlighting the characteristics and peculiarities of the problem. Finally, a real-life case study is solved.

Gebennini, Elisa; Grassi, Andrea; Rimini, Bianca; Gamberini, Rita

In a variety of industrial sectors rack storage is adopted for holding stock-keeping units (SKUs) between production (or purchasing from external supplier) and delivery. It is well known that, among the different types of rack storage, racks accessed in a Last-In-Fist-Out manner are the most economically convenient solutions. Nevertheless, especially when product shelf-life is critical as occurs in the food industry, the design of LIFO storage systems is not trivial. Thus, this paper presents an approach able to take into consideration two different measures for assessing the performance of a storage system, with the aim of assigning each item type in inventory to the optimal type of lane racks. Lastly, a significant case study from the food industry is discussed.

Gamberini, Rita; Lolli, Francesco; Rimini, Bianca; Torelli, M.; Castagnetti, E.

The problem of allocating jobs to a set of parallel unrelated machines in a make to stock manufacturingsystem is studied. The items are subdivided into families of similar products. Sequence-dependent setupsarise when products belonging both to the same family and to different families are sequenced. Restrictionson the number of available setups should be considered. The availability of planning batch production exists.Nevertheless, batch size is not known a priori. Hence, a solving approach considering both a preassignmentprocedure and a scheduling algorithm is proposed. Specifically, the focus of the paper is on thepre-assignment methodology: a pre-assignment model (solved by a commercial solver) and two heuristicsare presented and compared, in order to minimize the average idle residual capacity during the planninghorizon, while considering pejorative factors related with the split volumes of the same product on differentmachines, unsatisfied demand along with demand produced in advance in each time period. The applicationto a case study is finally described in order to assess the performance of the proposed approach.

Ferrari, Anna Maria; Barbieri, Luisa; Gamberini, Rita; Rimini, Bianca; Neri, P.; Pini, Martina

Life-Cycle Assessment (LCA) has been recognized as a valuable tool to investigate the environmental load of products as well as processes and services by evaluating energy, water and materials usage and environmental releases. On the basis of an LCA analysis it is possible to point out the critical stages of the life cycle and to improve the environmental performance of the investigated system. This research aims to evaluate the life cycle impact of a hard chrome plating process in order to identify the criticalities and to provide alternative solutions for reducing the environmental loads.

Lolli, Francesco; Gamberini, Rita; Regattieri, A.; Rimini, Bianca; Grassi, Andrea; Belluti, P.

Managing sporadic and irregular demand patterns represents a relevant issue in several industrial contexts. Two main aspects have to be underlined due to their prominence: the former is the problem of forecasting future demand profiles, and the latter choosing and determining the best re-order policy to be applied, in accordance with information gained during the forecasting step. In this paper the former issue is discussed, by focusing on the management of items with sporadic and irregular demand patterns that also present a seasonality component. TRAMO-SEATS is a versatile procedure that allows quick identification of the best SARIMA forecasting model from an available set. Results obtained by its implementation are compared with those obtained by the Croston (1972) and Syntetos-Boylan (2005) methods, which represent two modified versions of simple exponential smoothing, introduced in literature for forecasting mean demand size per period specifically in case of irregular and sporadic demand profiles. In particular, two items are analysed, with the aim of demonstrating that when the strict hypothesis required by Croston’s and Syntetos-Boylan’s approaches fails, alternative forecasting methods could be required. TRAMO-SEATS represents a promising and user-friendly option.

Gamberini, Rita; Lolli, Francesco; Rimini, Bianca

Managing irregular and sporadic demand patterns is a fundamental task in several real life contexts, such as spare parts consumption, multi-echelon supply chains or start-up production. This work is a study of re-order policies and stock inventory management approaches aimed at optimizing pre-defined performance indexes. Specifically, given a firm operating in the field of electric resistance manufacturing, the focus is on the application of different item clustering methods, in order to define groups of items with similar behavior that require similar management approaches. The work offers a framework for the comparative evaluation of two different item clustering methods, by means of a simulative approach, available when product demand profiles are irregular and sporadic. In order to compare them, a multi-criteria technique is preferable because of the high uncertainty of the cost structure. Hence, after running the simulation, three Key Performance Indicators (KPI) are estimated: the average inventory level, the average number of backorders that occurred and the average number of emitted orders. Finally, some conclusions are drawn by defining a field of implementation for each clustering approach studied.

Gamberini, Rita; Rimini, Bianca; Galloni, Luca; Baroni, A.

Cathode Ray Tubes (CRTs) adopted in TV sets and computer monitors represent a consistent portion of Waste Electrical and Electronic Equipment (WEEE). In comparison with the recycling of WEEE such as refrigerators or washing machines, the recovery process for CRT containing devices is very difficult. CRTs are composed of four types of glass (panel, funnel, neck and frit seal) with different compositions. Furthermore, dangerous substances are contained within (i.e. lead, barium, strontium and fluorescent dust). Hence, the need to define robust processes for the design and implementation of efficient facilities for CRT cutting arises. This work describes steps guiding the design and the experimental optimal setting of a prototype facility for water-jet cutting of CRTs, in order to obtain recyclable high quality glass. Initially, a version of the cutting facility with manual movement of the cutting tool is set, in order to evaluate expectable cutting results. Subsequently, a detailed setting of automated movement of the cutting tool is carried out, in order to improve the quality of obtainable glass. As a consequence, a water-jet cutting facility which guarantees the cutting of high quality CRTs is finally set and a prototype is implemented.

Rimini, Bianca; Grassi, Andrea; Gamberini, Rita; Gebennini, Elisa

This paper deals with analytical models of manufacturing serial lines where adjacent line stages (i.e. machines or work-stations) are decoupled by a finite buffer. Specifically, the aim is to take into account the inherent uncertainty arising from unpredictable, or predictable but not constant, disruptions of the manufacturing process. As regards production lines, since times to failure and times to repair can generally be assumed to be exponentially (or geometrically) distributed, Markov process models are suitable for performance assessment. On the other hand, Bernoulli process models are more appropriate in case of assembly lines. This work discusses some of the most popular Markov and Bernoulli models of manufacturing lines; then, an interesting extension, called “restart policy”, is presented. The new models with restart policy can be applied to a number of industrial production and assembly systems when it is important to reduce the probability of blocking events.

Rimini, Bianca; Grassi, Andrea; Gamberini, Rita; Gebennini, Elisa; Lolli, Francesco; Ferrara, A.

The paper describes a study of designing rack storage systems managed according to a Last-In Fist-Out (LIFO) policy. The system is supposed to house a number of cyclic items (i.e. characterized by batch production and continuous deliveries policies). This kind of behaviour is common for high-consumption products in the food industry, such as pasta and bakery products.The aim of the study is to define a static design solution by assigning each item to a number of LIFO racks so that the overall system performance results are satisfactory. The dynamic behaviour is kept under control by adopting automated material handling devices such as Automated Guided Vehicles (AGVs).This paper is an extension of a previous work by Ferrara et al. (2011), here named the single-allocation procedure, by allowing each item to be assigned to two different rack typologies (double-allocation solution).The convenience of the double-allocation solution in comparison with the single-allocation one is proven by a significant case study from the food industry.

Rimini, Bianca; Gamberini, Rita; Grassi, Andrea; Galloni, Luca; DE ROSA, A.; Reggiani, E.

Waste collection is a problem frequently attracting the interest of both academics and practitioners due to a continuously increasing number of laws addressing its efficiency and effects on humans and the environment when inefficiencies occur. In recent years, interesting results have been achieved through the use of innovative underground collection systems. Main expected effects are connected with improvements in pollutant and noise emissions during waste collection and transport, low obstruction to traffic during waste collection, small space requirement for collecting bins. Nevertheless, the design, production and installation process for these underground systems still remains a crucial aspect, given the strict deadlines that must be respected. Difficulties arise when customizations are required. Hence, project management is a key issue for ensuring expected results in terms of time, costs and perceived quality. In this paper, steps characterising project management in the field of underground waste collection systems, especially focusing on customised items, is analysed. Data obtained in a case study is commented on.

Regattieri, A.; Gamberini, Rita; Lolli, Francesco; Manzini, R.

Queues of people, products and machines frequently occur in many production and service systems, resulting in significant inefficiencies. This paper discusses the significant impact on these problems of the queuing theory introduced by Erlang and Kendall. A methodology based on the M/M/m queuing model (including a validation phase through a goodness-of-fit test) is proposed. This methodology makes parametric analyses of system performance according to the different possible ranges of input parameters. It helps solve several typical problems found in production systems (e.g., resource design, traffic and logistics analysis) and services (e.g., optimal design and management). There is a good tradeoff between the robustness of the results, coherence with real industrial systems and mathematical complexity. A real-world application involving the design optimisation of a passenger security screening system in an international airport is presented. In particular, the optimal number of security gates in the design is discussed.

Gamberini, Rita; Rimini, Bianca; Galloni, Luca; Baroni, A.

The treatment of Waste Electrical and Electronic Equipment (WEEE) is a topic of interest for researchers and practitioners due to directives and laws addressing Electrical and Electronic Equipment (EEE) end of life management along with the necesity of executing optimal management in order to assure profit to companies operating in such a field. Nevertheless, only recent contributions have proposed technologies and operative procedures for WEEE treatment. As a consequence wide data bases concerning occuring failures are rare. In this paper data concerning failures occuring in a WEEE treatment plant operating in Modena (Italy) are collected for a period nine months. Specifically, technologies and operative procedures for the treatment of Cathode Ray Tube (CRT) containing devices (i.e. televisions and computer monitors) and refrigerating devices are studied. Finally, corrective actions and modifications in adopted facilities and operative procedures are proposed, by supporting the study with the assessment of the environmetal impact associated with the presence or the absence of the main failures.

Gamberini, Rita; Lolli, Francesco; Rimini, Bianca; Sgarbossa, F.

Items with irregular and sporadic demand profiles are frequently tackled by companies, given the necessity of proposing wider and wider mix, along with characteristics of specific market fields (i.e. when spare parts are manufactured and sold). Furthermore, a new company entering into the market is featured by irregular customers orders. Hence, consistent efforts are spent with the aim of correctly forecasting and managing irregular and sporadic products demand. In this paper, the problem of correctly forecasting customers orders is analyzed by empirically comparing existing forecasting techniques. The case of items with irregular demand profiles, coupled with seasonality and trend components, is investigated. Specifically, forecasting methods (i.e. Holt-Winters approach and (S)ARIMA) available for items with seasonality and trend components are empirically analyzed and tested in the case of data coming from the industrial field and characterized by intermittence. Hence, in the conclusions section, well performing approaches are addressed.

Gamberini, Rita; Gebennini, Elisa; Manzini, R.; Ziveri, A.

The planning activity of Waste Electrical and Electronic Equipment (WEEE) collection networks is a topic of interest for researchers and managers, due to both the complexity of the problem and its important practical implications, in accordance with the guidelines that recent laws have addressed in a large number of industrialized countries. Nevertheless, even if these new legislation directives aim to reduce the critical effects of human activities on the environment, approaches for coupling the planning phase of a WEEE transportation network with the analysis of its environmental impact are rare in literature. Specifically, in this paper, a WEEE transportation network in the North of Italy (precisely, in the Reggio Emilia district) is addressed by means of an integrated solution approach. The methodological steps regard the following topics: data collection techniques, vehicle routing methods and heuristic procedures for creating different system scenarios, simulation modelling for obtaining solutions satisfying technical performance measures, LCA methodology for assessing the environmental impact of such solutions, multi-criteria decision methods for selecting the best choice under the joint technical and environmental perspective.

Gamberini, Rita; Galloni, Luca; Paese, S.; Rimini, Bianca

Waste collection is a problem recently involving researchers and practitioners. In order to address the adoption of well performing solutions, the necessity of technically and economically evaluating alternative waste management systems arises. Furthermore, the analysis of the effect following their adoption attracts interests, specifically in the field of sustainable development, due to both an increasing number of laws and directives directing the computation of the impacts on humans and the environment along with the increasing environmentally-consciousness of consumers. In this paper a user-friendly methodology that compares waste collection systems is described. Specifically, technical, economical and environmental performance indexes are evaluated (such as: pollutant emissions during waste transport and collection, noise during waste transport and collection, obstructions to traffic during collection, visual impact and space of bins, costs). Each aspect is qualitatively and quantitatively defined. An operative tool is created, implementing the described approach. Finally a case study is analysed, in order to demonstrate the effectiveness of the proposed approach. Specifically, traditional bulky-bins and innovative underground collection systems are compared.

Grassi, Andrea; Gamberini, Rita; Mora, C.; Rimini, Bianca

Risk assessment constitutes a critical phase of the safety management process. It basically consists of evaluating the risks involved in the execution of working activities, so as to provide the managers with information suitable to address intervention measures. The most important activity in risk assessment is the risk evaluation task but, despite its importance, national and international regulations have never formalized a standard methodology for addressing it, leaving companies complete freedom to adopt the approach they consider appropriate. As a consequence, companies generally settle on the use of simple methodologies which frequently are not able to emphasize all the main aspects affecting risk in the workplace and to produce a precise ranking of hazardous activities. In this paper, a new methodology for risk evaluation is then proposed with the aim to overcome limitations of the classical approaches. In particular, new factors are introduced to take into account effects of human behavior and environment on risk level, other than the classical injury magnitude and occurrence probability of an accident. The proposed methodology also integrates an estimative approach based on the fuzzy logic theory, which permits more coherence in the evaluation process, producing a very suitable final rank of hazardous activities. Finally, an actual case study is reported to show the capabilities of the new risk evaluation model.

2009 - A multiple single-pass heuristic algorithm solving the stochastic assembly line rebalancing problem [Articolo su rivista]
Gamberini, Rita; Gebennini, Elisa; Grassi, Andrea; Regattieri, A.

Assembly line rebalancing is a problem companies are frequently confronted with as continuous changes in product features and volume demand caused by the volatility of modern markets result in re-definition of assembly tasks and line cycle time fluctuations. Consequently, managers are forced to adjust the balancing of their lines in order to adapt to the new conditions while trying to minimise both increases in completion costs and costs related to changes in task assignment. In particular, when modifications are made to line balancing, costs are incurred for operator training, equipment switching and moving, and quality assurance. The stochastic assembly line rebalancing problem is essentially composed of a multi-objective problem in which two joint objectives, total expected completion cost of the new line and similarity between the new and the existing line, must be optimised. Consequently, this paper presents a multiple single-pass heuristic algorithm developed for the purpose of finding the most complete set of dominant solutions representing the Pareto front of the problem. The operative parameters of the heuristic are set as a result of a great deal of experimentation. Moreover, a multi-objective genetic algorithm is developed and then compared with the proposed heuristic in order to demonstrate its effectiveness. Finally, an illustrative case study is presented.

Gamberini, Rita; Lolli, F.; Rimini, Bianca; Torelli, M.

The problem of allocating jobs to a set of parallel unrelated machines in a make to stock manufacturing system is studied. The items are subdivided into families of similar products. Sequence-dependent setups arise when products belonging both to the same family and a different family are sequenced. Restrictions on the number of available setups should be considered. The availability of planning batch production exists. Nevertheless, batch size is not known a priori. Hence, a solving approach considering both a pre-assignment procedure and a scheduling algorithm is proposed. Specifically, the focus of the paper is on the pre-assignment methodology: a pre-assignment model (solved by a commercial solver) and two heuristics are presented and compared, in order to minimize the average idle residual capacity during the planning horizon, while considering pejorative factors related with the split volumes of the same product on different machines, unsatisfied demand along with demand produced in advance in each time period. The application to a case study is finally described in order to asses the performance of the proposed approach.

Gamberini, Rita; Gebennini, Elisa; Rimini, Bianca

The content of hazardous components in Waste arising from Electrical and Electronic Equipment (WEEE) is a major concern that urges governments and industry to take measures to ensure proper treatment and disposal. Thus, the European Union issued directives to encourage reuse, recycling and other proper forms of recovery of such waste while companies and academics are still studying methods and technologies for optimizing recovery processes. This paper presents an analysis of the logistics process assuring the correct collection, handling, transportation and storing of WEEE. The experience comes from an Italian WEEE treatment plant (TRED Carpi S.r.l.) where a new kind of container has been introduced in order to improve the logistics system. An evaluation framework is described and used in order to compare different system configurations and assess the advantages emerging from adopting proper equipments for WEEE transport and handling.

Gebennini, Elisa; Gamberini, Rita; Manzini, R.

The design and management of a multi-stage production–distribution system is one of the most critical problems in logistics and in facility management. Companies need to be able to evaluate and design different configurations for their logistic networks as quickly as possible. This means coordinating the entire supply chain effectively in order to minimize costs and simultaneously optimize facilities location, the allocation of customer demand to production/distribution centers, the inbound and outbound transportation activities, the product flows between production and/or warehousing facilities, the reverse logistics activities, etc.Full optimization of supply chain is achieved by integrating strategic, tactical, and operational decision-making in terms of the design, management, and control of activities. The cost-based and mixed-integer programming model presented in this study has been developed to support management in making the following decisions: the number of facilities (e.g. warehousing systems, distribution centers), the choice of their locations and the assignment of customer demand to them, and also incorporate tactical decisions regarding inventory control, production rates, and service-level determination in a stochastic environment. This paper presents an original model for the dynamic location–allocation problem with control of customer service level and safety stock optimization. An experimental analysis identifies the most critical factors affecting the logistics cost, and to finish, an industrial application is illustrated demonstrating the effectiveness of the proposed optimization approach.

Gamberini, Rita; Rimini, Bianca; Lolli, Francesco

In diversi settori della produzione industriale si sta sempre piùaffermando l’esigenza di progettare e produrre prestandoattenzione all’impatto ambientale. In questo contesto si collocala direttiva RoHS (Restriction of the use of HazardousSubstances), finalizzata a ridurre o eliminare l’utilizzo di alcunesostanze definite come genericamente pericolose. Questo articolo affronta l’analisi sperimentale dei costi di adeguamento alla suddetta direttiva in un’impresa di piccole-medie dimensioni che realizza cablaggi su commessa, nella quale la direttiva ha significativamente modificato i cicli tecnologici di saldatura, che tradizionalmente venivano effettuati con leghe di saldatura al piombo ora bandite dal mercato. In particolare, si è focalizzata l’attenzione sulle voci di costo di adeguamento alla direttiva che sono risultate più significative: costi di modifica dei cicli tecnologici e costi di stoccaggio. I risultati ottenuti confermano l’elevata incidenza sui costi di produzione che la direttiva RoHS genera nel caso di una piccola-media impresa.

Gamberini, Rita; Galloni, Luca; Rimini, Bianca; Beltrami, F.; Ori, M.

Waste collection services are usually executed by companies who win a public offer published by communities. Hence, the necessity of evaluating and comparing different methodologies for executing the services arises. Nevertheless, input data (i.e. the amount and the frequency of conferred waste, approaches adopted for service design, the service level satisfying community citizens) are often uncertain, as are the performance indexes strictly related with them. Alternatively, a comparison of output data, featuring the proposed services, can be carried out, in order to address future decisions.In this paper a monitoring scheme is proposed, in order to define data that need to be traced, along with results that can be obtained. Finally, a case study is analysed, in order to support the applicability and the effectiveness of the introduced approach.

Gamberini, Rita; Gebennini, Elisa; Rimini, Bianca; Spadaccini, E.; Zilocchi, D.

Low cost automation and poka yoke philosophy assure good results when applied to manufacturing processes with a high incidence of human operators, with a low availability of time for solution implementation and with expensive effects associated with errors in executing operative procedures. Hence, their joint adoption is addressed in order to access the benefits they bothguarantee. Specifically, in this paper, the case of a manufacturing line for heat exchangers is studied. Operative tools are redesigned in accordance with both low cost automation and poka yoke philosophy principles. Furthermore, since poka yoke solutions are subdivided between those preventing errors and those detecting them, the former are preferred. It emerges that LCA and poka yoke solutions adopted induce consistent improvements in the line productivity.

Gebennini, Elisa; Dallari, S.; Grassi, Andrea; Perrica, G.; Fantuzzi, Cesare; Gamberini, Rita

Automated Guided Vehicle (AGV) logistic handling systems are widely adopted when high transportation capacity and quality of service are the most important characteristics to reach. A large number of mathematical approaches have been developed in yearsto address AGV systems design and control. Nevertheless, proper performance estimations have to consider the peculiar aspects of the real environment in which the AGV system operates. A simple and effective approach to the stochastic features modelling is the discrete event simulation of the real system. This paper presents a conceptual approach that lead the analyst to set up consistent simulative models to address AGV systems design and performance estimation when applications in end-of-line logistics areconsidered.

Gamberi, M.; Gamberini, Rita; Manzini, R.; Regattieri, A.

This paper presents a new approach to evaluating the suitability of implementing a batch-production-oriented manufacturing line. The Characteristic Curve (CC) as introduced by Deming [Deming, D.D., 1959. When to shift to straight-line production. Harvard Business Review 38, 62–68.] is an efficient tool for determining the number of machines belonging to each station in single-model production lines. Because such an approach does not consider set-up times, it is inappropriate for batch-production-oriented lines. A new methodology is presented named Distributed Set-up times Characteristic Curve (DSCC) which enables application of the CC to manufacturing lines organized on a batch-production system. The innovation introduced is an analytical model able to consider frequent set-ups, such as those caused by batch switching. The importance of the proposed technique for production system designers is the speed of analysis and the possibility of avoiding simulations as presented in the case study application, where the optimal organization of a steel pipe manufacturing line is explored. Specifically, by analyzing technical and economical performance indicators, the optimal number of laser bits, curling machines, bar folders and welders belonging to manufacturing stations, along with the suggested size of production batches to be adopted, are evaluated.

Gamberini, Rita; Grassi, Andrea; Mora, C.; Rimini, Bianca

The optimal utilization of storage capacity is a key issue for companies with undersized warehouses, especially in situations where storage areas are expensive (i.e. warehouses with refrigeration systems). Since package size influences storage area design, in this paper an approach for jointly configuringsecondary packages, pallets and storage racks is introduced. In particular, the multi-item model version of the problem is studied. Three alternative storage policies are explored: random, class-based, and dedicated locations. Finally, a case study highlights the relevance of the proposed methodology to real-life situations.

Gamberini, Rita; Gebennini, Elisa; Grassi, Andrea; Mora, C.; Rimini, Bianca

An increased interest towards environmental respect amongstconsumers, managers and researchers is registered, owing both to changing sensitivity and guidelines described in technical regulations. In this scenario, the European Union (EU) directives 2002/96/EC and 2003/108/EC, controlling the management of Wastes of Electric and Electronic Equipments (WEEE) are well-inserted. Companies producing Electric and Electronic Equipments (EEE) become responsible for end of life steps of their products. Hence, great efforts are made to optimise both recovery networks and remanufacturing and recycling processes. This paper proposes an innovative model for recovery network management. Included is a case study.

Regattieri, A.; Gamberini, Rita; Lolli, F.; Manzini, R.

Queues of people, products, and machines frequently occur in many production systems (goods manufacturing and service supply) and result in significant inefficiencies. For example, machines waiting to be repaired may result in lost production, vehicles forced to wait before being unloaded may delay subsequent shipments, and people made to wait for a service (i.e. bank, hospital, supermarket) may become frustrated which could result in lost future business. This paper discusses the tremendous positive impact of queuing theory (introduced by Erlang and Kendall) on the problems typically found in production systems (e.g. optimal design, resources rationalization, traffic and logistics analysis). The fundamental models in this theory are discussed and then applied to the design and optimization of production systems. Finally, a real world application of M/M/n queuing theory is presented involving design optimization of a passenger security screening system in an international airport.

Manzini, R.; Gamberini, Rita

Nowadays global and extended markets have to process and manage increasingly differentiated products, with shorter life cycles, low volumes and reducing customer delivery times. Moreover several managers frequently have to find effective answers to one of the following very critical questions: in which kind of facility plant and in which country is it most profitable to manufacture and/or to store a specific mix of products? What transportation modes best serve customer points of demand, which can be located worldwide? Which is the best storage capacity of a warehousing system or a distribution center (DC)? Which is the most suitable safety stock level for each item of a company’s product mix? Consequently logistics is assuming more and more importance and influence in strategic and operational decisions of managers of modern companies operating worldwide.The Council of Logistics Management defines logistics as “the part of supply chain process that plans, implements and controls the efficient, effective flow and storage of goods, services, and related information from the point of origin to the point of consumption in order to meet customers’ requirements”. Supply Chain Management (SCM) can be defined as “the integration of key business processes from end-user through original suppliers, that provides product, service, and information that add value for customers and other stakeholders”. In the modern competitive business environment the effective integration and optimization of the planning, design, management and control activities in SCs are one of the most critical issues facing managers of industrial and service companies, which have to operate in strongly changing operating conditions, where flexibility, i.e. the ability to rapidly adapt to changes occurring in the system environment, is the most important strategic issue affecting the company success. As a consequence the focus of SCM is on improving external integration known as “channel integration”, and the main goal is the optimization of the whole chain, not via the sum of individual efficiency maximums, but maximising the entire system thanks to a balanced distribution of the risks between all the actors. The modelling activity of production and logistic systems is a very important research area and material flows are the main critical bottleneck of the whole chain performance. For this reason in the last decade the great development of research studies on SCM has found that new, effective supporting decisions models and techniques are required. In particular a large amount of literature studies deal with facility management and facility location (FL) decisions, e.g. the identification of the best locations for a pool of different logistic facilities (suppliers, production plants and distribution centers) with consequent minimization of global investment, production and distribution costs. FL and demand allocation models and methods object of this chapter are strongly associated with the effective management and control of global multi-echelon production and distribution networks. A few studies propose operational models and methods for the optimization of SCs, focusing on the effectiveness of the global system, i.e. the whole chain, and the determination of a global optimum. The purpose of this chapter is the definition of new perspectives for the effective planning, design, management , and control of multi-stage distribution system by the introduction of a new conceptual framework and an operational supporting decision platform. This framework is not theoretical, but deals with the tangible Production Distribution Logistic System Design (PDSD) problem and the optimization of logistic flow within the system. As a consequence the proposed optimization models have been applied to real case studies or to multi-scenarios experimental analysis, and the obtained results are properly discussed.

Gamberini, Rita; Regattieri, A.

Double pressing systems have recently been introduced to speed up and improve the pressing step of porcelain stoneware tiles. In this paper, double pressing systems using discontinuous pre-compaction are analysed, both technically and economically. Two operative conditions are considered: the traditional forming of tiles during pressing is compared with the innovative production of a unique large-sized slab, subsequently customized according to market requirements. Furthermore, manufacturing conditions are explored with infrequent or frequent production runs, due to increasingly smaller production batches, in order to evaluate which production process is more suitable when changing operative conditions are managed.The analysis is carried out experimentally, by collecting data in existing pilot plants, producing batches of products of different size and colour. Details are provided concerning the technical characteristics of the systems, along with costs per manufactured square metre for investments, personnel, maintenance, spare parts and electric power. A case in which some production days are reserved for each manufactured batch is compared to a case in which production runs are repeated more frequently in a day.Manufacturing large-sized slabs and customization has shown to be an efficient solution for companies operating in changing markets. Further research should study double pressing systems using continuous pre-compaction. The proposed analysis, by presenting an evaluation process and sharing data collected experimentally, provides innovative support for addressing decision makers when new pressing systems for porcelain stoneware tiles are selected.

Gamberini, Rita; Grassi, Andrea; Regattieri, A.

Assembly line re-balancing is a problem frequently tackled by companies, as continuous changes in product features and volume demand caused by the volatility of today’s markets produce assembly tasks re-definition and line cycle time fluctuations. Hence, managers have to adapt the balancing of their lines to accomplish with the new conditions, while trying to keep to a bare minimum increases in completion costs and in costs related to changes in tasks assignment. In particular, modifications in line balancing impact on operators training, equipment switching and moving, along with quality assurance. The stochastic assembly line re-balancing problem basically consists in a multi-objective problem where two objectives, total expected completion cost of the new line and similarity between the new and the existing line, have to be jointly optimized. In this paper, a multiple single-pass heuristic algorithm is consequently developed with the aim to find the most complete set of dominant solutions representing the Pareto front of the problem. Multiple single-pass procedures iterate the execution of single-pass algorithms, in order to generate a set of solutions, rather than to create a unique purpose. Given such a set, the best-performing solutions, in accordance with the multi-objective nature of the problem, are presented to the line designer, who selects the final assembly line balancing considering also additive factors that can be hardly inserted in a mathematical approach (i.e. simplicity of learning re-assigned tasks, time requested for the re-allocation of tools necessary for executing re-assigned tasks, experience requested for maintenance of tools necessary for executing re-assigned tasks). By means of a wide experimentation including comparisons with a multi-objective genetic algorithm, the behaviour of the proposed methodology is set and optimized.

Gamberini, Rita; Gebennini, Elisa; Grassi, Andrea; Rimini, Bianca

Ogni anno in Italia vengono dismessi alcuni milioni di elettrodomestici usati, di cui una percentuale significativa è costituita da apparati refrigeranti obsoleti, quali frigoriferi, congelatori e condizionatori. All’interno della macrocategoria dei rifiuti da apparecchiature elettriche ed elettroniche (RAEE), il frigorifero si presenta come un elettrodomestico particolarmente critico a fine vita. La ragione di ciò risiede nelle problematiche connesse al trattamento dei CloroFluoroCarburi dannosi per l’ozono stratosferico, degli oli esausti contenuti nel compressore e degli interruttori al mercurio. Tali considerazioni pongono in evidenza il problema dello smaltimento dei RAEE in impianti conformi alle norme vigenti in modo da evitare la contaminazione ambientale. La gestione del recupero dei RAEE in un impianto di trattamento si basa infatti sull’implementazione di metodologie di lavorazione in grado di intercettare e recuperare i CloroFluoroCarburi ed altre sostanze dannose mediante procedimenti di triturazione in ambiente controllato; tale tecnologia consente inoltre di ridurre la quantità di rifiuti destinati alle discariche e di recuperare materiali, quali rame, alluminio e ferro. Il presente studio riguarda l’analisi di un impianto di trattamento di RAEE eseguita presso il centro Tred Carpi S.r.l (Fossoli, Modena). Dapprima viene esaminato l’intero ciclo di lavorazione del frigorifero per poi focalizzasi sul dimensionamento di alcune attrezzature specifiche. Infine si procede alla valutazione dei costi e dei ricavi connessi a tutte le attività che sono indispensabili per il corretto funzionamento di un centro di trattamento di RAEE attualmente operativo: il valore aggiunto dello studio proposto consiste infatti nel presentare dati difficilmente reperibili in letteratura relativi a operazioni, attrezzature e personale di supporto all’impianto di triturazione e separazione vero e proprio, unitamente alle stime dei ricavi ottenibili dalla vendita dei materiali recuperati.

Grassi, Andrea; Gebennini, Elisa; Goldoni, G.; Fantuzzi, Cesare; Gamberini, Rita; Nevin, R.; Rimini, Bianca

The paper presents advanced issues in modelling and simulation of complex packaging line. In particular, we developed a theoretical model of a line with two machines and a buffer, which is a simplified version of a real packaging line from Tetra Pak company. The paper reports also about simulation results that confirm theoretical supposals.

Melacini, M.; Gamberini, Rita

I prodotti del sistema moda (vestiti, accessori,…) sono da sempre caratterizzati da un’estrema volatilità delle vendite, che si traduce in un numero significativo di articoli invenduti al termine della stagione. In questo articolo si presenta un magazzino, che, gestendo in maniera efficace ed efficiente la raccolta dei resi di stagione, ha consentito di trasformare una voce di costo in un’occasione diprofitto per l’azienda.

Gebennini, Elisa; Gamberini, Rita; Manzini, R.; Mora, C.

The design and management of a multi-stage production/distribution system is one of the most critical problem in logistics and in facility management. This manuscript deals with the so called facility location-allocation problem, i.e. with the simultaneous decisions regarding the design, management, and control of a distribution network. In particular the logistic problem object of this study deals with the determination of the number of facilities (e.g. production plants, warehousing systems, distribution centers, etc.), the choice of their locations and the assignment of customers demand to them, incorporating also tactical decisions regarding inventory control, production rates and service level determination.The purpose is to design, test, and compare innovative cost-based models and solutions for the dynamic (i.e. multi-period) location allocation problem (LAP) with safety stock levels determination and customer service level optimization. An experimental analysis conducted on an industrial application is presented and discussed.

Gamberini, Rita; Gebennini, Elisa; Grassi, Andrea; Mora, C.; Rimini, Bianca

La gestione del fine vita dei Rifiuti di Apparecchiature Elettriche ed Elettroniche (RAEE) è regolamentata, in Italia, dal D.Lgs. n. 151 del 25 Luglio 2005, che recepisce le direttive europee 2002/96/CEE e 2003/108/CEE. Le nuove direttive, facendo ricadere la responsabilità del recupero sui produttori di Apparecchiature Elettriche ed Elettroniche (AEE) e stabilendo l’obbligo, da parte dei rivenditori, di accettare gli elettrodomestici dismessi in seguito all’acquisto di nuovi prodotti, aumentano la complessità gestionale delle operazioni di raccolta. Emerge, quindi, la necessità di definire una metodologia in grado di ottimizzare le esistenti reti di recupero organizzando le attività di raccolta considerando le esigenze imposte dalla nuova normativa. Nel seguito, si presenta lo studio effettuato in collaborazione con TRED Carpi S.r.l., al fine di ottimizzare la raccolta dei RAEE nella provincia di Reggio Emilia.

Gamberini, Rita; Grassi, Andrea; Rimini, Bianca

In this paper a new heuristic for solving the assembly line re-balancing problem is presented. The method is based on the integration of a multi-attribute decision-making procedure, named ‘‘Technique for Order Preference by Similarity to Ideal Solution’’ (TOPSIS), and the well-known Kottas and Lau heuristic approach. The proposed methodology does not focus on the balancing of a new line, rather it takes into account the more interesting current industrial aspect of rebalancing an existing line, when some changes in the input parameters (i.e. product characteristics and cycle time) occur. Hence, the algorithm deals with the assembly line balancing problem by considering the minimization of two performance criteria: (i) the unit labour and expected unit incompletion costs, and (ii) tasks re-assignment. Particularly, the latter objective addresses the problem of keeping a high degree of similarity between previous and new balancing, in order to avoid costs related to tasks movements: operators training, product quality assurance, equipment installation and moving. To assess the performance of the presented approach a comparison with the original Kottas and Laumethodology is carried out. The results demonstrate the capability of the proposed algorithm of dealing with the multiobjective nature of the re-balancing problem. Solutions with advantages both in workload re-assignment, implying beneficial effects on the costs factors affected by tasks movements, and in completion costs are obtained in almost half of all problems solved. In the other cases, trade-off balancings with low increases in completion costs are presented.

Gamberini, Rita; Grassi, Andrea; Mora, C.; Rimini, Bianca

Performance and efficiency of production systems is hugely influenced by the capability to efficiently manage material flows. Even if today’s approaches are oriented towards applying lean-agile paradigms, in several industrial contexts, which are characterized by high complexity and personalization of products together with high volatility in demand, production scheduling remains one of the most profitable techniques for achieving acceptable levels of efficiency. As a matter of fact, the consistent amount of models proposed by scientific literature is not able to address the majority of aspects and constraints involved in real industrial contexts scheduling, while, on the other hand, commercial scheduling softwares mainly act as a simple task loader, thus not allowing to obtain high system performances. Within the aim of reducing this gap, a new framework for addressing job shop scheduling in real industrial contexts is presented in this paper. In particular, the classical graph representation of the job shop problem is extended to include constraints and characteristics typically found in a real shop floor. Moreover, new strategies are proposed to solve the problem and a representative case is reported to show the suitability of the new approach. Finally, guidelines are reported to address future developments.

Gamberini, Rita; Grassi, Andrea; Mora, C.

Flow-shop systems with machine bypass represent production approaches currently widely adopted in several industrial fields (i.e. electronic and belt industries). As a consequence of differences in the manufacturing process, in those systems, jobs are not forced to stop by each machine. Moreover, if a job does not need processing on a machine, it can skip that machine and the very job eventually residing there. In this paper, a new heuristic for solving the flow-shop scheduling problem with machine bypass is presented. The algorithm is able to manage several scheduling performance measures, finding a set ofnon-dominated solutions representing the Pareto front. The heuristic integrates a priority rule and a local search procedure with a Multi Attribute Decision Making (MADM) technique in such a way as to drive the search direction towards good trade-off solutions. To show the effectiveness of the proposed approach some computational results are presented.

Gamberini, Rita; Grassi, Andrea; Mora, C.; Rimini, Bianca

Strategic reasons have led companies to keeping warehouses, such as providing inventories for rapidly satisfying changeable customers demand, along with protecting against unexpected delays in the manufacturing process. However, warehouses involve costs, due to both their construction and their management. Hence, the optimal saturation of the available storage space is an important issue to be pursued. Since packages dimensions and features strictly influence pallet loading configuration, which affects warehouses capacity, in this paper an algorithm for concurrent package and warehouse design in accordance with the design for logistics principles is presented. Particularly, the case of random storage policy is considered, as a common method to manage warehouses. Finally, an application in an Italian pasta manufacturing company is presented.

Gamberini, Rita; Gamberi, M.; Manzini, R.; Regattieri, A.

Several economic studies carried out during the last years have highlighted that the porcelain stoneware tile is capturing great market’s shares. This product combines significant mechanical properties with the possibility to obtain special surface decorations. Hence, the optimization of its production process is cause of great efforts by manufacturers.This paper presents the results of a study, developed in partnership with an international group which produces facilities for Ceramics, focused on the innovation of porcelain stoneware tile production process.The main idea is to customize ceramic products (tiles) obtained from a single large-sized slab. Hence, either cutting facilities for un-dried and unfired tiles or for fired tiles are adopted. Moreover, the substitution of traditional presses with innovative double pressing systems is explored.Particularly, a comparison both in technical and economic perspective between the traditional production process and manufacturing systems coupling the aforementioned innovations are presented.

Gamberini, Rita; Grassi, Andrea; Mora, C.; Rimini, Bianca

The recovery, recycle and remanufacturing of a product at the end of its life is recently receiving much attention, due to the growing interest in the reverse supply chain. Greater attention to the environment, the development of waste regulations and competition in industry as regards product recovery lead to the creation of reverse logistics networks. This paper deals with the evaluation of the environmental and social impact of the reverse supply chain, through the use of Life Cycle Analysis methodology, the results of which can be used for policy and strategy decision-making. This paper investigates the reverse supply chain of electrical and electronic equipment (RAEE) and in particular it concerns the life cycle assessment of an household refrigeration, in order to analyze the environmental and economical impact of its closed supply chain.

Regattieri, A.; Gamberi, M.; Gamberini, Rita; Manzini, R.

This paper deals with effective forecasting methods for typically lumpy demand for aircraft spare parts, and analyzes the behavior of forecasting techniques when dealing with lumpy demand. Twenty forecasting techniques are considered and tested and historical data from Alitalia are used to analyze and compare their performance. The results demonstrate that item lumpiness is the dominant parameter and show that demand forecasting for lumpy items is a complex problem; results from previous studies are not very accurate. The best approaches are found to be weighted moving averages, the Croston method, and exponentially weighted moving average models.

Gamberini, Rita; Grassi, Andrea; Mora, C.; Rimini, Bianca

Il settore delle lavorazioni meccaniche per conto terzi e della realizzazione di componenti meccanici su commessa, è da sempre caratterizzato da scarsa ripetibilità dei prodotti e dalla necessità di seguire le specifiche del cliente, spesso note solo dopo l’acquisizione dell’ordine. In questo contesto, caratterizzato da produzione intermittente o frammentaria e da volumi di produzione medio-bassi, risulta essere fondamentale l’implementazione della programmazione e del controllo della produzione e la attendibilità dei dati di ingresso dello schedulatore a capacità finita, relativi ai tempi di lavorazione e di collaudo. In particolare le fasi di collaudo e di controllo qualità presentano un’elevata criticità per la realizzazione di componenti high tech di lavorazione meccanica, sia perché devono essere schedulate in più punti del ciclo tecnologico, sia per l’elevata difficoltà di stimarne la durata. Esse, infatti, sono fortemente dipendenti dall’esperienza e dalla capacità dell’operatore e risultano essere apparentemente non correlate alle caratteristiche del pezzo. In questa memoria viene presentata una metodologia pratica ed innovativa che permette la stima dei tempi di collaudo di un componente a partire dal suo disegno costruttivo, in funzione delle caratteristiche tecniche del pezzo. La determinazione di tempi standard e la valutazione a priori dei tempi relativi alle fasi di progettazione, programmazione e di running dell’operazione di collaudo di componenti meccanici, permettono di ottenere una buona stima dei tempi necessari per eseguire il controllo qualità, in funzione della schedulazione dell’intero processo produttivo. L’applicazione di questa metodologia ad un’azienda di medie dimensioni, che opera nel settore delle lavorazioni meccaniche di piccola serie e di prototipi, ha dimostrato la bontà della stima dei tempi di collaudo, ottenuti a partire dai disegni costruttivi dei componenti presi in esame.

Gamberini, Rita; Grassi, Andrea; Mora, C.; Rimini, Bianca

Già da parecchi anni, le piccole-medie imprese del settore italiano delle vernici si sono orientate verso una produzione di tipo batch, per fronteggiare le pressanti richieste, da parte del mercato, di ampliamento del mix produttivo, di riduzione della quantità da produrre per tipologia di prodotto e di tempi di consegna sempre più restrittivi. Questo ha portato al conseguente aumento dei livelli di scorta di prodotti finiti, per garantire un elevato livello di servizio al cliente. La contemporanea esigenza di raggiungere la riduzione dei costi di capitale immobilizzato rende necessaria l’adozione di un sistema produttivo che permetta di abbattere i tempi di attraversamento del prodotto. In questo contesto si inseriscono i paradigmi della lean production e dell’agile manufacturing che, tra le altre cose, puntano alla riduzione dei tempi di risposta, al raggiungimento di un elevato livello qualitativo e alle riduzione del capitale immobilizzato. La filosofia del modello ibrido di lean-agile manufacturing è stata quindi applicata in un colorificio reggiano di piccole-medie dimensioni. L’individuazione di un punto di disaccoppiamento, tramite l’analisi critica delle composizioni chimiche, ha permesso di suddividere il processo produttivo in due fasi. La prima consiste nella realizzazione di un premiscelato, comune a diversi codici di prodotto finito, mentre l’altra riguarda la personalizzazione del prodotto in presenza delle precise specifiche del cliente. Per rendere efficace il processo produttivo così ottenuto, si è quindi proceduto ad una sua riconfigurazione, allo scopo di identificare le potenzialità produttive e le necessità di stoccaggio del premiscelato stesso. I vantaggi della modularizzazione del prodotto si esplicitano in una maggiore rapidità di risposta e nel miglioramento del controllo qualitativo del processo. Per migliorare ulteriormente la qualità percepita dal cliente si è inoltre introdotta una classificazione dei prodotti secondo fasce di tonalità omogenee, che permettono la consegna di vernici di colore uniforme al medesimo cliente.

Manzini, R.; Ferrari, E.; Gamberi, M.; Gamberini, Rita; Pareschi, A.; Regattieri, A.

This paper concerns with the evaluation of the fulfilment process in an inventory/distribution multi-echelon system by the application of dynamic simulation. The generic supply chain is made of one or more warehouses, N-retailers and several customers. The performance of the generic fulfilment logistic channel, expressed in terms of customer service level and overall costs, depends on the behaviour of each one of itsentity (supplier, warehouse, retailer, etc.), on the adopted strategies and policies (reorder policy, centralization vs. decentralization, safety stocks management, order batching, replenishment time, lot sizing) and finally on the neighbourhood operating conditions (demand rate, holding and replenishment costs, supply lead times). A factorial analysis on the most critical factors affecting the performance of the whole system is conducted.

Gamberini, Rita; Grassi, Andrea; Mora, C.; Rimini, Bianca

Gli aspetti inerenti il consumo e l’approvvigionamento di energia elettrica e termica stanno rivestendo un ruolo sempre più importante nel sistema ospedaliero. In tale settore, in passato è stata quasi esclusivamente rivolta attenzione verso la qualità del servizio offerto, mentre oggigiorno, anche come conseguenza dei sempre più restrittivi vincoli di spesa, si comincia a prendere atto che alcuni interventi per il contenimento dei costi dell’energia possono essere posti in opera senza portare ad una riduzione del livello di servizio. In quest’ambito, l’adozione di impianti di cogenerazione per la produzione combinata di energia elettrica e termica rappresenta una valida alternativa all’impiego dei tradizionali metodi di approvvigionamento. Per contro, la loro installazione comporta un notevole esborso iniziale. La realizzazione di una buona progettazione e di una corretta valutazione dei tempi di recupero dell’investimento diventano quindi fondamentali per poter mettere in luce la reale convenienza che deriva dall’adozione di tali sistemi. Nella presente memoria è quindi presentato lo studio di fattibilità di un impianto di cogenerazione a gas naturale destinato a servire un importante ospedale situato in Umbria. Lo studio, dopo aver affrontato in una prima fase tutti gli aspetti tecnici e progettuali, mostra come la soluzione cogenerativa possa portare a notevoli convenienze economiche con tempi di recupero dell’investimento più che accettabili.

Gamberini, Rita; Grassi, Andrea; Gamberi, M.; Manzini, R.; Regattieri, A.

Despite the most of the published papers regarding the assembly line balancing problem consider straight-lines configurations, an increasing number of researchers recently point up advantages related with U-shaped lines. Literature presents only a few number of algorithms for balancing such a line type. The main difference between the straight-lines and the U-shaped lines models concerns the identification of the available operations to be assigned to a station. In the former case, each task can be assigned to a station only after its predecessors have been allocated, whereas in the latter, available operations are those whose both predecessor and successor tasks are assigned. Thus, solving approaches to balance a U-shaped line can be obtained by the application of modified techniques for straight-lines. In this paper an innovative heuristic methodology is proposed for solving the U-shaped version of the balancing problem with the aim of minimizing both labour and incompletion costs. Moreover, an algorithm for re-balancing an existing line is presented. An existing balance may change in order to accommodate modifications in cycle time, tasks completion times, precedence constraints. The necessity of a procedure for minimizing differences between the new and the initial balancing solutions is emphasized in accordance with tasks movements which involve several time consumption and costs in changing system configuration, moving and installing equipments, preparing workers, etc. The proposed model is based on a multi-objective approach to obtain valuable compromises between costs minimization and tasks re-assignment. Finally a wide experimentation in a large family of simulated scenarios is carried out to assess the suitability of the proposed procedures.

Gamberi, M.; Manzini, R.; Bevilacqua, M.; Gamberini, Rita

La variabilità del mercato odierno richiede una continua evoluzione ed innovazione dei prodotti offerti ed una loro sempre più spinta diversificazione. L’introduzione del concetto d’automazione flessibile ha segnato il passaggio da politiche aziendali mirate alla produzione di grandi volumi di merci standardizzate a politiche “market-oriented”, all’interno delle quali ci si scontra sovente con una personalizzazione sempre più spinta dei prodotti offerti con il fine di soddisfare segmenti di mercato diversificati. In quest’ottica, l’obiettivo del presente lavoro è quello di proporre un nuovo approccio alla “curva caratteristica di prodotto” per estendere tale metodo di analisi alle situazioni aziendali che nella pratica si osservano più di frequente: decidere la convenienza del passaggio da una politica di produzione di tipo job-shop ad una di tipo flow-shop nel caso di produzione monoprodotto a lotti. In tale memoria, si è cercato di adattare il modello di Deming, di CCT (produzione monoprodotto in linea) a condizioni aziendali in cui i tempi di fermo impianto (per set-up, manutenzione ecc.) non possono essere trascurati nella normale pianificazione della produzione: lotto singolo monoprodotto ma con tempo di set-up rilevante rispetto al tempo disponibile e multilotto monoprodotto con fermo impianto obbligato tra due lotti consecutivi.

Gamberini, Rita; Grassi, Andrea; Mora, C.; Rimini, Bianca

In questa memoria è presentata una metodologia innovativa per la valutazione del rischio nell’ambito della gestione della sicurezza industriale. Oggigiorno il rischio di un evento è generalmente valutato mediante il prodotto di due indici numerici, di cui uno rappresentante la probabilità di accadimento e l’altro indicativo della magnitudo dei danni conseguenti all’evento stesso. Questo modo di affrontare il problema presenta diversi limiti in termini di completezza e di robustezza dell’analisi, in quanto: (i) oltre alla frequenza di accadimento ed alla magnitudo, vi sono fattori di natura umana e ambientale che devono essere considerati al fine di ottenere una più efficace valutazione del rischio, (ii) le valutazioni dei diversi fattori sono spesso affette da incertezza, e quindi non dovrebbero essere analizzate secondo i rigidi canoni della matematica classica e (iii) un indice di rischio calcolato come prodotto di più fattori presenta una scarsa significatività in quanto, non essendo in scala lineare, risulta notevolmente suscettibile alle variazioni dei singoli giudizi. Al fine di superare i suddetti limiti, è stato esteso il modello di rischio classico identificando nuovi fattori di valutazione ed è stata adottata una nuova metodologia di analisi, basata sull’integrazione di una tecnica multi attributo (Technique for Order Preference by Similarity to Ideal Solution, TOPSIS) con la matematica fuzzy. La metodologia sviluppata costituisce quindi uno strumento affidabile, in grado di fornire la classificazione di un insieme di eventi di rischio rispetto a più fattori di analisi, anche se suscettibili ad incertezze di valutazione. Per dimostrare l’applicabilità e l’efficacia del metodo proposto è infine riportato un esempio concreto riguardante la gestione della sicurezza in un’industria alimentare.

Gamberini, Rita; Grassi, Andrea; Mora, C.; Rimini, Bianca

La memoria presenta un algoritmo innovativo per il bilanciamento delle linee di montaggio manuali, di tipo Single-Model a cadenza imposta, operanti su prodotti soggetti a modifiche, come conseguenza di personalizzazioni richieste dal mercato. La complessità del problema nasce dalla necessità di riassegnare i carichi di lavoro alle stazioni costituenti la linea ogni volta che si deve abbandonare la realizzazione di un prodotto per avviare la produzione di una versione differente e, contemporaneamente, dalla necessità di ridurre i tempi di risposta del sistema produttivo. A tal fine, il bilanciamento della linea dovrà essere ridefinito limitando le variazioni nei gruppi di operazioni assegnate alle stazioni nella precedente configurazione, mantenendo comunque contenuti i costi. La metodologia proposta contempla questo obiettivo ricercando le soluzioni che minimizzano sia (i) i costi totali attesi di montaggio che (ii) le modifiche nell’assegnazione delle operazioni alle stazioni. Il modello è basato sull’integrazione di una tecnica multi obiettivo, denominata Technique for Order Preference by Similarity to Ideal Solution (TOPSIS), con il noto euristico di Kottas e Lau. In particolare, è stata adottata la versione Multiple Single-Pass al fine di ottenere diverse soluzioni candidate, tra le quali il decisore possa scegliere quella che più si addice alle sue esigenze. L’efficacia dell’approccio proposto è evidenziata mediante la simulazione di una linea di assemblaggio di gruppi elettrogeni, in cui, per assecondare nuove richieste del mercato, si sostituisce il prodotto realizzato con una versione caratterizzata da requisiti di maggiore leggerezza.