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This paper presents an innovative Universal Multi-Parametric Model for designing devices using Magneto Rheological Fluids based on the explication of relationships between the functional requirements and the corresponding combination of related properties (chemical and physical)A rationale thus results to select the best MRF for a specific application. This might constitute a useful tool providing organized knowledge on the MRF world for scholars and practitioners approaching to the world of MRF technology as well as a support to engineers/designers during the early design tasks. more...

With the constant increase of energy costs and environmental impacts, improving the process efficiency is considered a priority issue for the manufacturing field. A wide knowledge about materials, energy, machinery, and auxiliary equipment is required in order to optimize the overall performance of manufacturing processes. Sustainability needs to be assessed in order to find an optimal compromise between technical quality of products and environmental compatibility of processes. In this new Industry 4.0 era, innovative manufacturing technologies, as the additive manufacturing, are taking a predominant role. The aim of this work is to give an insight into how thermodynamic laws contribute at the same time to improve energy efficiency of manufacturing resources and to provide a methodological support to move towards a smart and sustainable additive process. In this context, a fundamental step is the proper design of a sensing and real-time monitoring framework of an additive manufacturing process. This framework should be based on an accurate modelling of the physical phenomena and technological aspects of the considered process, taking into account all the sustainability requirements. To this end, a thermodynamic model for the direct laser metal deposition (DLMD) process was proposed as a test case. Finally, an exergetic analysis was conducted on a prototype DLMD system to validate the effectiveness of an ad-hoc monitoring system and highlight the limitations of this process. What emerged is that the proposed framework provided significant advantages, since it represents a valuable approach for finding suitable process management strategies to identify sustainable solutions for innovative manufacturing procedures. more...

Metal additive manufacturing is growing its impact on high-tech industrial sectors so far. The capability to recover and repair worn components, with costs that are gradually more affordable, is giving a boost to the development of these technologies. The direct laser metal deposition (DLMD) technology is taking a leading role in this domain. Manufacturing components, with high mechanical properties, require a careful process design and a continuous control. The monitoring of the thermal field thus assumes a crucial role in processes in which high-power sources are involved. Thermal treatments influence the microstructure, morphology and the grain size of the depositions indeed, which determine high-performance standards. In this work, an ytterbium fibre laser source was used to build single-track depositions of a nickel-based superalloy powder on a substrate of the same material. Temperature field monitoring was performed using a high-frequency (100 Hz) IR thermal camera, allowing an accurate monitoring of peeks temperature, thermal cycles and thermal gradients. Thermal data and process parameters were compared with metallographic analysis to capture the relation between the geometrical and microstructural characteristics of clads. The study focuses on the influence of the powder feed rate and energy density on thermal parameters. An innovative approach to the solidification map method, commonly implemented with numerical simulations of welding and additive manufacturing, has been successfully applied to experimental data giving results consistent with the literature. more...

The direct laser metal deposition (DLMD) is an emerging technology in the additive manufacturing field, which is becoming widely adopted in several industrial applications. The optimal selection of process parameters is critical, given the cost of physical tests and the requirement for high-quality manufacturing. Correct forecasting of process parameters using predictive physical models is a viable alternative to shorten the setup phase and improve the sustainability. In this paper, firstly, several models available so far in the literature are reviewed, and then, a general model is derived to evaluate the best combination of process parameters in single track operations. The proposed phenomenological model allows simple forecasting based on three main process parameters: laser power (P), powder feed rate (F) and translation speed (V). An innovative approach is proposed to generalise the model and overcome the “try and error” method used in numerous works to determine the exponents (α, β, γ). The model was designed considering the physical parameters which best explained the variability of the exponents: the thermal diffusivity of the base material and the density of the powder material. The best ranges of the process parameter exponents are suggested to establish the most suitable combined parameters for the prediction of geometric characteristics of the clad. The potentialities of the model are proven based on an experimental case performed over a commercially available Nickel-based super-alloy powder. New formulations are recommended, which are in good agreement with the behaviours defined in the literature, as shown in the test case. more...

The effect of mixing suspended nanoparticles into a bi-disperse magneto-rheological fluid on sedimentation phenomena is explored. A reference bi-disperse MRF has been modified using a ferrofluid containing magnetite nanoparticles of two shapes (spheres or hexagonal platelets) suspended in paraffin-oil as carrier fluid. The reference MRF was prepared with a mixture of two diameter sizes for the micrometric particles. The reference MRF was also prepared using two different grades of carbonyl-iron micrometric particles (herein these will be referred to as HARD and SOFT), which differ each other for their mechanical properties. The experiment monitored the evolution with time of the sediment-supernatant interface. This experiment showed that the presence of nanoparticles (particularly the spherical ones) slows down the sedimentation effects in terms of ratio and rate, independently of the other characteristics of the fluid. This study also showed that fluids based on SOFT carbonyl iron powders, in presence of nanospheres, are more stable than HARD carbonyl iron powder based fluids, since their sedimentation rate slows down in the long term. At the same time, HARD particle-based magnetorheological fluids show smaller sedimentation ratios than SOFT based fluids. more...

International audience; A Cyber-Physical-Social System (CPSS) is an emerging research trend that focuses on integrating the social dimension into Cyber-Physical System (CPS). The CPSS consists of social, physical, and cyberspaces. There is a lack of influential theories and design approaches to reach a unified structure of a CPSS. Furthermore, the impacts of a CPSS on the sustainability performance of systems and processes are still unexplored. The paper addresses this latter research issue by evaluating case studies on CPSSs discussed in the literature. more...

International audience

Sustainability of buildings and constructions is almost a mandatory feature nowadays. New low-cost solutions are quite often pursued for increasing the structural and aesthetic quality of the manufactured units. This paper discusses a new idea of a modular component easy-to-assemble for low-cost structural arches on site, mainly for civil building applications. The related producibility issues are also discussed by presenting an appropriate manufacturing process able to propose a modular technology that could be easily implemented at industrial level, thus widening the use of easy-to-mount arches for civil buildings. The new concept of dimension stones, the different and appropriate use of materials may allow the reduction of resource consumption and assure the sustainability of the arches according to the proposal here discussed. The idea of a new assembled modular arch is here supported by scientific and technical evidences to show the potentialities for its use in real applications. The prototype of this modular arch has been subjected to static experimental tests whose results are discussed also by means of a numerical model able to predict the actual behaviour. more...

International audience; The digital twin has received strong interests from researchers and industries since it allows predictive manufacturing by integrating the cyber and the physical space. An important prerequisite for the cyber-physical integration is a proper and highly-accurate digital model. Considering the complexity of digital modelling, the paper aims at developing and using predefined modelling patterns to enable building digital models independently of the specific application domain. The idea is explored and validated on a real case study by designing a set of patterns to create a digital twin model prototype adopted to control and optimize the manufacturing system taken into account. more...

International audience; Manufacturing enterprises are facing the need to align themselves to the new information technologies (IT) and respond to the new challenges of variable market demand. One of the key enablers of this IT revolution toward Smart Manufacturing is the digital twin (DT). It embeds a “virtual” image of the reality constantly synchronized with the real operating scenario to provide sound information (knowledge model) to reality interpretation model to draw sound decisions. The paper aims at providing an up-to date picture of the main DT components, their features and interaction problems. The paper aims at clearly tracing the ongoing research and technical challenges in conceiving and building DTs as well, according to different application domains and related technologies. To this purpose, the main questions answered here are: ‘What is a Digital Twin?’; ‘Where is appropriate to use a Digital Twin?’; ‘When has a Digital Twin to be developed?’; ‘Why should a Digital Twin be used?’; ‘How to design and implement a Digital Twin?’; ‘What are the main challenges of implementing a Digital Twin?’. This study tries to answer to the previous questions funding on a wide systematic literature review of scientific research, tools, and technicalities in different application domains. more...

Direct metal laser deposition (DMLD) is an additive manufacturing technique suitable for coating and repair, which has been gaining a growing interest in 3D manufacturing applications in recent years. However, its diffusion in the manufacturing industry is still limited due to technical challenges to be solved—both the sub-optimal quality of the final parts and the low repeatability of the process make the DMLD inadequate for high-value applications requiring high-performance standards. Thus, real-time monitoring and process control are indispensable requirements for improving the DMLD process. The aim of this study was the optimization of deposition strategies for the fabrication of thin walls in AISI 316L stainless steel. For this purpose, a coaxial monitoring system and image processing algorithms were employed to study the melt pool geometry. The comparison tests carried out highlighted how the region-based active contour algorithm used for image processing is more efficient and stable than others covered in the literature. The results allowed the identification of the best deposition strategy. Therefore, it is shown how this monitoring methodology proved to be suitable for designing and implementing the right building strategy for DMLD manufactured 3D components. A fast and stable image processing method was achieved, which can be considered for future closed-loop monitoring in real-time applications. more...

International audience

Today, the Life Cycle Assessment (LCA) is the most employed tool for assessing the sustainability of products and processes, both from an environmental, social and economic point of view. Exergy is defined by literature as the amount of useful work that can be derived from a real system when it is brought into equilibrium with its environment. In the literature, it is considered an outstanding concept that can be applied to enhance the effectiveness of ordinary evaluation models such as LCA. The literature proposes a variety of hybrid approaches that combine Exergetic Analysis (EA) and LCA with different combination frameworks. The aim of this paper is to describe the potential of each hybrid method and to characterize the degree of interoperability between EA and LCA that each of them can provide. Nevertheless, there are drawbacks that seem to be too challenging to overcome: a variety of inconsistencies in the interpretation of the results due to the difficulty of the inventory phase and the ambiguity in the choice of the correct alternative in the standard databases; the link with old techniques that refers to obsolete approaches in finding data that suit to the updated goals and scopes; the difficulty in conducting an assessment affected by the least possible uncertainty. Following a theoretical overview of the principles of each hybrid method that binds EA and LCA, the authors want to provide a review from a completely different point of view than the state-of-the-art literature, on how effectively EA and LCA can interact with each other in order to provide a more holistic view of the system/process to be assessed. The fascinating circumstance that emerges from the review is that any exergy approach would be more effective if joined (not replaced) to the standard LCA, because it turned out to be complementary. This theory has long been developed by many authors in their case studies as a confirmation of what Gutowski wrote years ago: no single alternative criteria or subsidiary model, independently of how well aggregated, may offer a suitable answer for all conditions. Specifically, through this review, the practitioners would be able to choose the best suited hybrid methodology, according to their aims, join the outcomes together and achieve a transdisciplinary knowledge of the behavior of the study case system, in order to design the best improvement strategies. more...

International audience; This article presents and compares the characteristics of most studied energy storage techniques, their technological development status, and performances highlighting the advantages of Vanadium redox flow battery. In more details, this article aims to describe the principal characteristics and the challenges of the vanadium redox flow battery. The challenges focus on three different aspects, namely membrane development, electrolyte optimization and electrode development underlining the precipitation problems of the vanadium ions, transportation issues and costs in vanadium redox flow batteries. Different methods and solutions have been presented in this article for overcoming these problems, defining also progress in the large-scale vanadium redox flow battery. more...

This review critically evaluates the latest trends in fuel cell development for portable and stationary fuel cell applications and their integration into the automotive industry. Fast start-up, high efficiency, no toxic emissions into the atmosphere and good modularity are the key advantages of fuel cell applications. Despite the merits associated with fuel cells, the high cost of the technology remains a key factor impeding its widespread commercialization. Therefore, this review presents detailed information into the best operating conditions that yield maximum fuel cell performance. The paper recommends future research geared towards robust fuel cell geometry designs, as this determines the cell losses, and material characterization of the various cell components. When this is done properly, it will support a total reduction in the cost of the cell which in effect will reduce the total cost of the system. Despite the strides made by the fuel cell research community, there is a need for public sensitization as some people have reservations regarding the safety of the technology. This hurdle can be overcome if there is a well-documented risk assessment, which also needs to be considered in future research activities. more...

International audience; Manufacturing enterprises are presently facing with an array of industry 4.0 (I4.0) challenges. "Digital requirements" need to be really assessed by an accurate analysis and deep understanding of the operational and technological criticalities in the manufacturing operations. It is required to structure a monitoring strategy for industry 4.0 that contains: 1. The definition of the measuring parameters. 2. The application of the sensor. 3. The execution of the measurement. The goal in fact is to present and to analyse the monitoring strategy adopted in a design for the digital transformation of a real Italian SME company: Master Italy s.r.l. Master Italy s.r.l. is a SME Italian company producing small accessories for civil window frames, is here considered to implement a monitoring strategy. The monitoring strategy is a hybrid approach between the life cycle analysis (LCA) and the exergetic analysis (EA) based on the evaluation of the mass balance (Fig.1.) and the energy balance (Fig.2.). LCA is an analytical tool used to quantify and to interpret the flows to-and-from the environment through the whole life cycle of a product, process or service. LCA appreciates quantities of elements flowing in the processes (say, energy, materials, etc.) but it depends on standard databases. The exergetic analysis is a thermodynamic method [1] that permits to: • Evaluate the quality of energy usage. • Identify and quantify the energy inefficiency of the process. Life cycle analysis (LCA) enables to identify the critical manufacturing process and the critical product of the company in terms of resource consumption and pollutions (green line). The critical process and the critical product in analysis are respectively the die casting aluminium and the steel corner (Fig.1 and Fig.2). The exergetic analysis allows to: 1. Split the manufacturing process in different subsystems. 2. Identify the critical subsystem evaluating the contribute of the exergy loss (E xloss). 3. Define the critical parameters to control. Die casting is a metal casting process that is characterized by forcing molten metal under high pressure into a mould cavity. The injection cycle of die casting aluminium process is composed by four different phases: 1. Melting: the aluminium enters at the solid state and exits at the molten state. 2. Injection: the molten aluminium is transferred, thought a plunger, into a chamber where it is injected into the mould. 3. Moulding: the molten aluminium solidifies in the mould cavity. 4. Extraction: an ejection mechanism pushes the casting out of the mould cavity. The optimization criterion of the monitoring strategy is to minimize the term E xloss , since the exergy loss is proportional to the generated entropy and this one is responsible for the less-than-theoretical efficiency of the system. The application of the exergetic analysis shows that the moulding phase (Subsystem 3) is the critical subsystem because the exergy loss is highest than other subsystems (Fig.1 and Fig.2). The first goal of the monitoring strategy, for Industry 4.0 implementations, is to select and to define where, what and why to sensorize (red rectangle). more...

International audience; Despite the recent growing interest in the " factory smartness " , still there are few small and medium enterprises (SMEs) that adopt effective I4.0 solutions. The main reasons can be related to the lack of formalized processes, lack of ICT knowledge as well as low-cost commercial systems. To cope with these issues, this work focuses on the development and the application of an approach to provide SMEs with a multipurpose , modular, knowledge-based system: the main aim is to provide a modular and extensible system that can be incrementally implemented without requiring a huge initial investments. This system is based on a core design-knowledge metamodel. From this core metamodel, multi-purposes modules can be built: in this paper, we present modules for the traceability support, the AR-powered assembly support, the machine-to-machine control and the data analysis support. more...

The manufacturing trend nowadays seems to be in contrast with the ecosystem needs, as it is based on the exploitation of limited natural resources. A new paradigm is now driving manufacturing in the direction of sustainability: the green and circular thinking. This latter can now guide SMEs in optimizing its processes and products to be more eco-friendly, and this in turn may lead to significant competitive advantages. The purpose of the study is to analyze the environmental lifecycle performance of a 100% PET fabric used for the outer cover of bed mattresses made by an Italian company, with looms of recent technology (2009–2010). The emissions defined in the community labeling system for textile products and mattresses have been taken into account as well as the mid and final impact categories established by the guidelines for the Product Environmental Footprint developed by European. Results show that the fiber and yarn production processes are the most impacted due to transport from China and the use of Chinese electricity grid mix (rich in coal). Furthermore, the disposal of fabric is another environmental critical point. In order to evaluate the improvements in the environmental sustainability of supply of PET yarns and the disposal phase, a number of scenarios were analysed, while a Monte Carlo simulation was performed to evaluate the sensitivity of the results respect to data uncertainty. A number of recommendations for the textile sector are provided, useful to assure sustainability of production. Critical points to achieve environmental labeling are highlighted and new data about textile, not already available in databases and literature, are provided due to the company's engagement. Finally, hints on the best recycling process of the product are given. more...

The increasing rate of production and diffusion of photovoltaic (PV) technologies for industrial and domestic applications urges improvement of the sustainability of their demanufacuring processes in order to reduce the amount of electronic wastes. Sustainability of demanufacturing processes concerns the reduction of energy consumption, the reduction of polluting substances as well as the reduction of the effort spent in recovery of the components. No optimal process exists so far, provided a number of different approaches have been devised. A promising choice relies on the use of thermo-mechanical treatments for inducing a delamination process where interfacial bonding between layers are weakened and, finally, broken inducing delamination of the layers. In this view, the paper presents a preliminary theoretical industrialization study. We introduce a mathematical model based of the equations of thermo-elasticity to prove the feasibility of the technological process; the results of a Finite Element (FE) Analysis are then discussed to show the validity of the new sustainable demanufacturing process endeavouring the delamination process. The analysis is performed searching the optimal thermally induced cycles at cryogenic temperatures. more...

The reliance on fossil fuels is one of the most challenging problems that need to be dealt with vigorously in recent times. This is because using them is not sustainable and leads to serious environmental issues, such as: air pollution and global warming. This condition affects economic security and development. An alternative to fossil fuel is highly possible which will be more environmentally friendly, sustainable and efficient as well. Among all the different technologies associated with renewable energy, fuel cell technologies represent one of the most promising technological advancement to curb the situation. In this paper, an overview of the technology and its advantages and disadvantages compared with competitive technologies was revealed. The application of different fuel cell types in the stationary and portable sectors was covered. Furthermore, recent challenges and promising developments of current fuel cell technologies in different studied applications were reviewed. Some possible solutions to the challenges were named in this paper for both the portable and stationary fuel cell applications. The paper further seeks to expose the world to the current progress made in the fuel cell industry up to date and possible areas that needs intensified research and modifications to make the fuel cell industry more vibrant and buoyant. more...

In this paper, hybrid laser-MAG (metal active gas) welding of twinning-induced plasticity (TWIP) and dual-phase (DP) steels with austenitic stainless steel (AISI316) was simulated by means of the finite element method. A thermo-mechanical model, which uses a 3D heat sources, was developed using the software Simufact Welding. The calculated dimensions, shape and distortion of the weld were compared with the experimental results, thence the model was validated. The metallurgical transformations for the DP steel were evaluated using the continuous cooling transformation (CCT) diagram and the calculated cooling rate. The numerical model predicted accurately the shape of the molten pool, the thermal cycles as well as the geometrical distortion of the butt weld. Therefore, the numerical model showed a good reliability and its potential for further development. more...

The number of scientific papers in the field of Sustainable Manufacturing (SM) shows a strong growth of interest in this topic in the last 20 years. Despite this huge number of publications, a clear statement of the profound meaning of Sustainable Manufacturing, or at least a strong theoretical support, is still missing. The 6R framework seems to be a first attempt to rationalize this issue, as it is an axiomatic identification of its true nature. Recognizing the pursuing of one or more of the Reduce-Recycle-Reuse-Recover-Redesign-Remanufacture principles allows users to identify if any manufacturing action is in the right direction of sustainability. In the paper, the authors speculate on the use of this framework and its possible extension by referring to all the existing scientific contributions on Sustainable Manufacturing in the SCOPUS® databases as a source of data. Starting from the measurement of the distribution of the scientific papers allocated onto the 6Rs dimensions, by using both author keywords and automatically extracted multiword from texts, the distribution of the scientific papers among the 6R was derived. A new framework is proposed based on analytical text tools to compare the affinity of the applied research activities of the Italian Technologist network SOSTENERE to sustainable manufacturing and provide also a benchmarking view to describe the Italian way to SM with respect to the rest of existing applications. more...

Among the enabling technologies of the fourth industrial revolution, additive manufacturing (AM) is considered as a key factor for the success of the new production paradigm.

Part 14: Data Management for Collaboration in Value Creation Networks; International audience; The digital transformation of collaborative networked manufacturing enterprises requires building and applying digital models representing the set of resources and processes knowledge. Modelling such digital copy of the physical system to perform real-time validation and optimization is quite complex and thus needs a big amount of data and some modelling patterns representing the operational semantics of the modelled elements. Generally, the modelling action has a specific application type. For this reason, the core challenge of the digital transformation modelling is to create a modular "digital model", namely a decomposable and re-composable model, towards different applications. The authors propose an approach based on the combination of data-driven and model-driven approaches, to identify and formalize modelling patterns, that combine for developing a modular executable model of the studied system. more...

International audience; Manufacturing organizations are facing the urge to adopt new strategies like sustainability to be able to respond to the market and customer's demand for sustainable products due to the scarcity of the natural resources or government policies. To serve this purpose, the main questions risen are "How sustainability is defined through its dimensions? and What sub-dimensions can denominate sustainable manufacturing? Focusing on the questions, this study is cantered by a systematic literature review based on sustainability, its dimensions and subdimensions to investigate sustainability in manufacturing and the domains on which manufacturers can act on to be more "sustainable". Although the literature is more focused on the three traditional dimensions of sustainability namely: environmental, economic and social, a more detailed look through the dimensions is needed to help manufacturing organizations sketch their own sustainable strategies on more specific issues. The study of the dimensions led to a hierarchy of importance for the traditional three, in which environmental dimension of sustainability showed to be conspicuous. Therefore, the dimension was chosen for the further analysis conducted by Formal Concept Analysis (FCA) on its sub-dimensions to explore the trends in their combination by manufacturers while trying to reach sustainability. more...

Electrical energy production from renewable sources has dramatically grown in the recent years in the developed countries, putting the hard problem to be solved of supply discontinuity. How to reach high efficiency and reliability of electrical energy storage system is thus now one of the most challenging goals to be reached: among all, one of the most simple and widespread to use is the electrochemical storage systems. This paper analyzes the sustainability of a small vanadium redox flow battery performed by an LCA approach. This electrical energy storage system was selected for its significant advantages in use, such as the almost infinite lifetime of the vanadium electrolytes, which represent a potentially significant advantage in terms of a sustainable future made of less fossil fuels and more renewable energy. In fact, the LCA analysis performed shows that the production of the battery has a moderate impact, including the effect toxicity while at the end of life, the material and the electrolyte are completely reusable with a small fraction that goes to landfill disposal. more...

International audience; Organizations are struggling to survive in today's competitive market. They are mostly obliged to meet customers' expectations and demand for sustainable products from one side and comply with governmental rules and regulations regarding energy, resources, materials, etc. on the other side. Therefore, measuring their sustainability performance and trying to keep up with the competitors is essential for their future development. Consequently, organizations' perception of operational sustainability can reveal their strategies on how to be sustainable, endeavouring the three pillars of economic, environmental and social. The present work investigates the role of indicators' choice and their meaning for sustainability assessment of manufacturing organizations. To this point, an analysis is conducted on the sustainability assessment of 100 manufacturing organizations using GRI indicators for assessing their sustainability state. A Formal Concept Analysis was run to look over the indicators and their interpretations to reach a given degree of sustainability of the organization. more...

Assessing sustainability of manufacturing is a fundamental prerequisite to the improvement of efficiency or effectiveness of manufacturing processes. The LCA is used to estimate the resource consumption along the life-cycle, while the exergy analysis introduces hints about the quality of resource consumption. The hybrid analysis descending from combining these two approaches has been proved to be a powerful tool to recognize the process optimization opportunities, as well as improvements and/or innovation paths of manufacturing processes. The incoming Industry 4.0 paradigm, providing new on-time information on the process status, is going to strongly improve this approach. The article analyzes the existing hybrid approaches and their potential features by the grace of an industrial case of an Italian SME where the Industry 4.0 is taking place. The company redesigned its sensing systems and partially the manufacturing organization as a function of the manufacturing predictability. more...

Decision concerning manufacturing process design and management, under sustainable constraints, are difficult to draw when taking into account variability of process conditions. Life-cycle analysis and exergetic analysis are even more jointly adopted to improve the accuracy of resource use efficiency – the so-called hybrid approach – even though these are based on the assumption of constant operating conditions. The paper discussed a new idea to take into account variability in hybrid exergetic LCA due to contingent conditions, by proposing an exergetic control-chart (ExCC) scheme to formalise the variable conditions. The idea behind the ExCC approach is that manufacturing sustainability analysis may change its outcomes when taking into account this ‘dynamic’ point of view. The control-charting scheme here proposed provides a mean to formalise explicitly the effects of variability in time, under the real operating conditions. The main advantage of the approach is to allow a more complete view of the process and to drive hints for improvements or innovations of processes. A real industrial case here presented of an Italian SME explains the potentialities of the idea as well as the limits of the current hybrid approaches available. more...

The development and implementation of the smart factory paradigm seems to be a must almost widespread all over the Western manufacturing companies so far. This article explores the application of exergetic analysis models as a feasible approach to customize such an announced paradigm shift: the implementation criteria as well as the true expected benefits are, in fact, far to be clearly understood or even perceived. An Italian medium enterprise located in the south of Italy operating in the automotive sector is adopted as a test bench. The standard use of exergetic model was adopted to assess and improve the sustainability of the manufacturing processes performed by the company, namely: turning, milling, grinding, plating and dehydrogenation. This thermodynamic view of the processes, on the other hand, represented a guideline to design a smart factory solution, and thus to structure the critical variables and the paths to digitalize processes for the intelligent control of the core production processes. more...

Published in IFAC-PapersOnline, 51(11):921-926, 2018; International audience; Six sigma is a well-assessed methodology for optimizing the performance of the enterprise through the reduction of the variability of their process outputs. Six sigma implementation consists of the development of the DMAIC phases to improve existent processes. Each phase of this methodology adopts statistical as well as qualitative tools to fix variability sources and assess the process to a six sigma level of quality. However, there is a lack of an implementation model on how to guide effectively the implementation of the methodology DMAIC. This is particularly true for SMEs that not have enough human resources for supporting the needed knowledge. To answer to this limitation of six sigma, the objective of this paper is to present a framework to support the implementation of six sigma approach in SMEs. This framework is formalized by a meta-model, which is based on different studies on six sigma, its phases and its tools. This framework aims to propose a solution to validate the passage between the DMAIC phases defining the requirements to be satisfied during each phase. more...

International audience; Highly customized products with shorter life cycles characterize the market today: the smart manufacturing paradigm can answer these needs. In this latter production system context, the interaction between production resources (PRs) can be swiftly adapted to meet both the variety of customers' needs and the optimization goals. In the scientific literature, several architectural configurations have been devised so far to this aim, namely: hierarchical, heterarchical or hybrid. Whether the hierarchical and heterarchical architectures provide respectively low reactivity and a reduced vision of the optimization opportunities at production system level, the hybrid architectures can mitigate the limit of both the previous architectures. However, no hybrid architecture can ensure all PRs are aware of how orienting their behavior to achieve the optimization goal of the manufacturing system with a minimal computational effort. In this paper, a new " hybrid architecture " is proposed to meet this goal. At each order entry, this architecture allows the PRs to be dynamically grouped. Each group has a supervisor , i.e. the optimizer, that has the responsibility: 1) to monitor the tasks on all the resources, 2) to compute the optimal manufacturing parameters and 3) to provide the optimization results to the resources of the group. A software prototype was developed to test the new architecture design in a simulated flow-shop and in a simplified job shop production. more...

To assess the sustainability of waste management scenario with energy recovery, it is necessary to carry out an adequate analysis of all influential criteria. The main problem in the analysis is to determine the indicators that clearly and fully sublimate the most important influential factors. The model for the assessment of the sustainability of waste treatment scenarios based on multi-criteria analysis AHP (analytic hierarchy process) method is developed. The model predicts an increase in the number of indicators, if it found that a selected number of indicators are not sufficient to distinguish between scenarios and new criterion for the selection of indicators: the relevance of the indicator for certain waste treatment. The model is verified in the case study the city of Nis. Four scenarios were selected and examined: business as usual scenario (landfilling of waste) and the other are created as scenarios with energy recovery and recourses preserving: composting organic waste with recycling inorganic waste, incineration of waste and anaerobic digestion of waste. The assessment of the sustainability of waste treatment scenarios was made in several steps. It is found that the best sustainable scenario is composting of organic and recycling of inorganic waste. more...

The paper proposes a methodology for the optimal dispatch of energy sources in hybrid and isolated energy systems. The proposed approach is based on the formulation and solution of a nonlinear discrete optimization problem aimed at optimizing input and output time trajectories for a set of combined generating and storage technologies. Loads and interruptible loads are among controlled variables, and are modeled according to their interruption costs. The approach is general enough to be applied to any hybrid system configuration and was developed having in mind the complex hybrid system architectures comprising several competing storage technologies (battery, pumping, and hydrogen). Test results are aimed at showing the feasibility of the proposed methodology, comparing optimal trajectories to suboptimal system behavior given by load-following strategies. more...

Optimisation problem concerning material flows, to increase the efficiency while reducing relative resource consumption is one of the most pressing problems today. The focus point of this study is to propose a new visual benchmarking approach to select the best material-flow path from the depot to the production lines, referring to the well-known Capacitated Vehicle Routing Problem (CVRP). An example industrial case study is considered to this aim. Two different solution techniques were adopted (namely Mixed Integer Linear Programming and the Ant Colony Optimization) in searching optimal solutions to the CVRP. The visual benchmarking proposed, based on the persistent homology approach, allowed to support the comparison of the optimal solutions based on the entropy of the output in different scenarios. Finally, based on the non-standard measurements of Crossing Length Percentage (CLP), the visual benchmarking procedure makes it possible to find the most practical and applicable solution to CVRP by considering the visual attractiveness and the quality of the routes. more...

The increasing rate of production and diffusion of photovoltaic (PV) technologies for industrial and domestic applications urges improvement of the sustainability of their demanufacturing processes in order to reduce the amount of electronic wastes. Sustainability of demanufacturing processes concerns the reduction of energy consumption, the reduction of polluting substances as well as the reduction of the effort spent in recovery of the components. There is not an optimal process so far, provided a number of different approaches have been devised (see e.g. [1, 2, 3]). A promising choice relies on the use of thermo-mechanical treatments for inducing a delamination process where interfacial bonding between layers are weakened and, finally, broken inducing separation of the layers [4]. In this paper we present a preliminary industrialization study, based on Finite Element (FE) Analysis, to prove the validity of the new sustainable demanufacturing process endeavouring the delamination process. The analysis is performed searching the optimal thermally induced cycles at cryogenic temperatures. We finally show that it is possible to induce the delamination according to specific operating temperatures. more...