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SEISM is a compact ECR ion source operating at 60 GHz developed up to 2014. The prototype uses a magnetic cusp to confine the plasma. This simple magnetic geometry was chosen to allow the use of polyhelix coils (developed at the LNCMI, Grenoble) to generate a strong magnetic confinement featuring a closed ECR surface at 2.1 T. The plasma is sustained by a 300 kW microwave pulse of 1 ms duration and with a 2 Hz repetition rate. Previous experiments at LNCMI have successfully demonstrated the establishment of the nominal magnetic field and the extraction of ion beams with a current density up to ~ 1A/cm². The presence of "afterglow" peaks was also observed, proving the existence of ion confinement in a cusp ECR ion source. The last run was prematurely stopped but the project restarted in 2018 and new experiments are planned in 2021. A new transport beam line has been designed to improve ion beam transport towards the beam detectors. Short- and long-term research plans are presented, including numerical simulations of the beam transport line and future upgrades of the ion source with the main goal to transform the high current density measured into a real high intensity ion beam., Proceedings of the 24th International Workshop on ECR Ion Sources, ECRIS2020, East Lansing, MI, USA

International audience; Various optimization tools have been used in industry to facilitate production planning at different levels of aggregation. Choosing the interoperability mechanisms of these systems, such as the planning frequencies, the information passed between them and the interpretation that other systems must make of them, has always been a challenge. This work focusses on production planning at the tactical and operational levels in North American sawmills, a commodity industry characterized by volatile prices and a divergent production process with coproduction. In this context, tactical planning produces aggregated plans, and information from these plans can be used as targets and/or constraints at the operational level (e.g., quantities to be produced/kept in stock per product and per period, sales targets, etc.). A simulation of this production system was therefore developed, encompassing the planning process and the market dynamic, to compare and evaluate the impact of different coordination approaches on business economic performance. Results showed that the type of information which should be shared from the tactical level to the operational level varies according to several factors, including the company’s order acceptance policy, price seasonality, and the presence or absence of overcapacity on the market

IF=3.954; International audience; This editorial introduces the special issue in the Elsevier journal Computers in Industry that analyses how the digital transformation of manufacturing is speeded up by two important drivers: cloud services and resource virtualization, which are vital for implementing the main building blocks - Cyber Physical Production Systems and Industrial Internet of Things - in the “Industry of the future” framework. The context of this special issue is firstly presented, with a specific focus on the federative concept of Industry 4.0. A framework characterizing research activities led in the field of the digital transformation of manufacturing processes and systems is then introduced. This framework is used to present and position the 12 papers composing the special issue. Perspectives are finally introduced as a guideline for future work in the digital transformation of manufacturing through cloud services and resource virtualization

International audience; It is now accepted that using multi-agent systems (MAS) improve the reactivity to treat perturbation(s) within flexible manufacturing system. Intelligent algorithms shall be used to address these perturbation(s) and all smart decision entities within their environment have to continuously negotiate until their common and final goal is achieved. This paper proposes a negotiation-based control approach to deal with variability on a manufacturing system. It has initially formulated and modeled an environment in which all contributing entities or agents operate, communicate, and interact with each other productively. Then after, simulation and applicability implementation experiments on the basis of full-sized academic experimental platform have been conducted to validate the proposed control approach. Product and resource entities negotiate considering different key performance measures in order to set best priority-based product sequencing. This has been done with expectations that the applicability of the negotiation-based decision-making will be more adaptable to deal with perturbation(s) than another alternative decision-making approach called pure reactive control approach. The result showed that negotiation among the decisional entities has brought significant improvement in reducing makespan and hence conveyed better global performance of a manufacturing system.

It is now accepted that using the multi-agents system (MAS) augments the reactivity to treat disturbances within flexible manufacturing system. Each agent could have different capability (evolution, learning, etc.) and the whole physical and control system, based on the agent interaction, could lead emerging behaviors to dynamically adapt a production schedule. Intelligent control algorithms shall be used to define these variables and all smart entities within their environment have to continuously negotiate for their final common goal. This paper proposes a negotiation-based reactive control approach to deal with the variability on manufacturing processes. A simulation experiment on the basis of full sized academic experimental platform was used to test how the negotiation-based reactive control approach could optimize priority based product sequencing. The product and resource agents have been built to negotiate considering different production performance measures. This has been done with expectations that the applicability of the negotiation-based reactive decision making process will be more adaptable to a production change than myopic decisions.

International audience; The North American lumber industry produces mostly commodity products (i.e. products with standard dimensions and properties). However, some customers also want products showing very specific characteristics. Because sawing involves co-production (many different types of lumbers are obtained from a single tree), sawmills do not know how the introduction of a new " speciality " product will affect quantities for the other products they also produce. We propose a simulation-optimisation based framework to tackle the kinds of problems such as these, where classical formulations cannot be used. A log breakdown simulator is used in combination with a tactical planning model in order to realise Sales and Operations Planning. The plan gives the information to the decision maker about which orders for speciality products should be accepted, what to produce and when, as well as the equipment settings to use and the raw material to buy/consume at each period. Through an industry-inspired case study, we show how the framework can lead to substantial benefits.

Development of future industry has become an active research area in the recent years. A structured national workgroup, called IMS2, has emerged in France over the last decade. The aim of this paper is, regarding four highlighted general research topics (namely agility, new technologies, sustainability, and industrial dissemination), to synthetize the general research works on intelligent manufacturing and to demonstrate the principal contributions developed within the framework of this national workgroup. After a critical evaluation of the proposed approaches toward alternative solutions, this paper suggests a 2030 roadmap for the workgroup.

International audience; The emergence of Cyber Physical System has dramatically impacted the use of traditionally centralized control system in responding to unexpected events. Rush order is quite common unexpected event in the current dynamic market characteristics and has significant perturbing ability to a centrally predictive schedule. This paper is aimed to propose a Consensus algorithm for Multi-agent based Manufacturing system (CoMM) to control the rush order and henceforth minimize a makespan. Consensus is an algorithmic procedure applied in control theory which allows convergence of state between locally autonomous agents collaborating for their common goal. Leader-Follower communication approach was used among the multi-agent to deal with the perturbing event. Each agent decides when to broadcast its state to neighbor agents and the controlling decision depends on the behavior of this state. The consensus algorithm is initially modeled by networking all contributing agents. After this, it is validated with simulation experiment based on academic full-sized application platform called TRACILOGIS platform. The results showed that the consensus algorithm has significantly minimized the impact of rush order on makespan of manufacturing orders launched on a system.

Les systemes MRP ont evolue a la fin des annees 1990 vers des modules « Advanced Planning Systems » ( APS ). Cet article decrit dans une premiere partie comment ces outils repondent a differentes situations de planification strategique, tactique et operationnelle (conception de reseaux, planification sous contraintes, plan d’allocations et de transport, remise de delais). La seconde partie presente leur contribution en termes de synchronisation des decisions selon les niveaux de planification et les maillons de la supply-chain. A travers 3 exemples, la derniere partie contrebalancera ces avantages par leur principal inconvenient : l’accroissement de la variabilite.

Laser plasma acceleration (LPA) with up to several GeV beam in very short distance appears very promising. The Free Electron Laser (FEL), though very challenging, can be viewed as a qualifying application of these new emerging LPAs. The energy spread and divergence, larger than from conventional accelerators used for FEL, have to be manipulated to fulfil the FEL requirements. On the test experiment COXINEL (ERC340015), the beam is controlled in a manipulation [1,2] line, using permanent magnet quadrupoles of variable strength [3] for emittance handing and a decompression chicane equipped with a slit for the energy selection, enabling FEL amplification for baseline reference parameters [2]. The electron position and dispersion are independently adjusted [4]. The measured spontaneous emission radiated by a 2 m long 18 mm period cryo-ready undulator exhibits the typical undulator spatio-spectral pattern, in agreement with the modelling of the electron beam travelling along the line and of the afferent photon generation. The wavelength is easily tuned with undulator gap variation. A wavelength stability of 2.6% is achieved. The undulator linewidth can be controlled., Proceedings of the 39th Free Electron Laser Conference, FEL2019, Hamburg, Germany

The recent spectacular development of laser plasma ac- celerators that now can deliver GeV electron beams in an extremelyshortdistancemakesthemverypromising. Ap- plications for light sources based on undulator radiation and free electron laser appear as an intermediate step to move from an acceleration concept to an accelerator qual- ification. However, the presently achieved divergence and energy spread require some electron beam manipulations. The COXINEL test line was designed for enabling Free Elec- tron Laser operation with baseline reference parameters. It comprises variable permanent magnet quadrupoles for di- vergence handling, a magnetic chicane for electron energy sorting, a second set of quadrupole for chromatic focusing and an undulator for synchrotron radiation emission and/or free electron laser gain medium. The transport along the line is controlled [1]. The synchrotron radiation emitted by the undulator radiation is studied under different conditions of detection (CCD camera, spectrometer), electron beam manipulation and undulator parameters. These observations pave the way towards Laser Plasma Acceleration based Free Electron Laser., Proceedings of the 10th Int. Particle Accelerator Conf., IPAC2019, Melbourne, Australia

International audience; In wireless sensor networks, the aim of storage protocols is to efficiently replicate data across nodes and to improvedata collection and querying by sinks. Among them, in-network storage protocols replicate data in a set of nodes thatdepends on some characteristics such as network topology and geographic location. Researchers have proposed varioustechniques to implement in-network storage. In this article, we summarize and highlight the key ideas of existing proto-cols which are further classified into three categories (reactive, unstructured proactive, and structured proactive) basedon topology, load balancing, transmission strategy, and reliability. Benefits and drawbacks of each protocol are studiedand compared with different requirements. Finally, future research directions are provided for efficient in-network stor-age in wireless sensor network.

International audience; A communicating object, or connected object, is a key element of the Internet of Things to shift a perceptible real world into a wide digital virtual world known as the cyber-physical system. Knowing that sustainability, safety, and logistic issues are among the significant goals and challenges of modern industrial enterprises, the communicating object can be a rele- vant concept to guarantee safety performance in logistics and warehouse management. This article presents the impacts and advantages of the communicating object in smart logistics and the design of a communicating object model inspired from Internet of Things European research projects, which controls and monitors safety risks in a hazardous and chemi- cal industrial context. Generic safety-based scenarios are presented, which rely on a set of negotiated interaction mechanisms for storage and picking. The relevant deployment of intelligence in a warehouse management system leads to propose a new concept called ‘‘IoT-controlled Safe Area.’’ Our contribution is to bring informational, communica- tional, and decisional capabilities close to the warehousing physical world thanks to the communicating object. This enables achieving safety assurance with a decrease in the decision-making delay and an increase in the solving efficiency of local and dynamic disruptions, while avoiding inherent shortcomings of the warehouse management system centraliza- tion. For this, an industrial implementation is presented.

Editorial du Numéro spécial : Emerging ICT concepts for smart, safe and sustainable industrial systems; International audience; This editorial introduces the special issue on Emerging Information and Communication Technology (ICT) concepts for smart, safe and sustainable industrial systems in the Elsevier journal Computers in Industry. The 13 papers in this special issue were selected because of their high quality and also because they propose emerging ICT solutions that address at least one of the three dimensions we suggest are basic requirements to design usable future Industrial Systems that must be safe, smart and sustainable. Previous global discussions about the state of the art with regard to the topic of this special issue are provided, as well as exploratory guidelines for future research in this area.

National audience; Quality policy has an impact on the production flows control by the way of the reworks rate. The using of a quality management approach, as TQM, is useful but however often inadequate. The proposed approach must be seen as a supplement to such quality management. This approach is broken down into two steps. The goal of the first one is to reduce the reworks rates by tuning optimally and on line the process in function of the lot characteristics and the values of the environmental factors. This tuning uses a model linking the different influent factors with the default occurrence. This model is extracted from the production dataset by using a learning approach. It is used to simulate an experimental design in order to find the optimal tuning of the controllable parameters. The second step evaluates the impact of the residual reworks rates on the production flows. It uses a combination of different indicators in order to obtain a cartography of the considered workshop that highlights different workshop behavior areas. The final goal is to associate the good production control rule to each of these areas. All this approach is applied to the case of a manufacturer of high-finished lacquered panels.; Le pilotage de la production est fortement dépendant des opérations relatives à la qualité des produits obtenus, car la non-qualité engendre des reprises qui vont fortement perturber les flux de production (boucles de retour, attentes, reprises, …). Si la mise en place d'une approche de management de la qualité telle que la TQM est indispensable dans cette optique, elle est malheureusement bien souvent insuffisante. La méthodologie proposée dans cet article arrive en appui et complément d'une telle démarche et repose sur deux étapes principales. La première a pour but de limiter la non-qualité, et donc réduire les taux de reprises, en déterminant, en-ligne, le réglage optimal du processus en fonction des caractéristiques du lot considéré et de l'état de l'environnement. Ce réglage repose sur l'utilisation d'un modèle reliant les différents facteurs au risque d'occurrence des défauts générant une non-qualité. Ce modèle est construit par apprentissage à partir des données de production. Il est utilisé dans un deuxième temps pour simuler un plan d'expériences afin de déterminer les réglages optimaux des paramètres contrôlables. La deuxième étape consiste à évaluer l'impact des taux de reprises résiduels sur la perturbation des flux. Une combinaison d'indicateurs est proposée qui permet de mettre en évidence différentes zones de comportement de l'atelier, l'objectif étant d'associer une règle de pilotage optimale à chacune de ces zones. L'ensemble de l'approche est déployée sur un cas industriel dans l'entreprise Acta-Mobilier, fabricant de panneaux laqués haut de gamme pour les cuisinistes, stands, mobiliers de magasins….

The rapid development of Internet of Things has triggered the multiplication of communication nodes based on Radio-Frequency Identification (RFID) and Wireless Sensor Networks (WSNs) in various domains such as building, city, industry, and transport. These communication nodes are attached to a thing or directly included in the material of the thing to form a communicating material. In communicating material, one of the desired objectives is to merge the logical data with its physical material, thus simplifying the monitoring of its life cycle, the maintenance operations, and the recycling process. In this context, the initial form of the communicating material can evolve during its lifecycle. It can be split, aggregated with other materials, or partially damaged. However, the entire information in the material should always be accessible after each change. Thus, the objective of this research is to develop specific algorithms for efficient dissemination of information in the material in order to limit information losses. Two dissemination algorithms hop-counter-based and probabilistic-based are proposed for storing data by using WSNs, and non-localized and localized storage is considered. Non-localized storage ensures that information can be retrieved from each piece of the material by using a uniform data replication process. Localized storage ensures that the information is stored in a limited region of the material. Castalia/OMNeT++ simulator is used to compare the performance of the proposed algorithms with other similar protocols such as DEEP, Supple, and RaWMS. This work focuses on the definition of new communicating materials (e.g. concrete and wood brick) using Wireless Sensor Networks.In this article, thousands of micro-sensors nodes are embedded into the material. Thus, the data could be stored in the memory of sensor nodes.New unstructured proactive data dissemination algorithms are developed to store the information in the communicating materials.A simulation study is developed using Castalia/OMNeT++ Tools.The solutions are compared with the most known unstructured proactive data dissemination protocols for Wireless Sensor Networks.

International audience; Sawmilling activities in softwood mills (i.e., wood-sawing, drying, and finishing) cannot be efficiently planned at the operational level in a centralized manner because of the complexity of the production process. Sawmills plan their activities in a decentralized manner (although they try to coordinate them). Thus, specific mathematical models have been developed over the years to support planning for each activity. In the literature, these planning models are usually evaluated and tested independently, or connected using heuristics and evaluated for a fixed demand–planning horizon, assuming a known demand for the entire planning period. In this study, we simulate the use of planning models for decentralized sawmill production, but in a context where new orders arrive randomly and replanning is carried out periodically using a rolling horizon. We also simulated and evaluated different coordination mechanisms at the operational level, highlighting that previously published coordination mechanisms for decentralized planning of sawmilling operations may lead to a low order-fill rate when used in such a dynamic environment. We then propose a more advanced push–pull coordination mechanism based on the concept of decoupling point, revealing that this new mechanism may be more appropriate regarding the market characteristics considered in the study, while leading to a sales increase and reduced inventory. Actual numbers vary depending on specific market conditions.Lumber production for softwood mills involves three main production stages: sawing, drying, and finishing. Many products are generated from a single raw material, so the process is known as divergent (from one log several products are obtained) with uncontrolled coproduction, which means that several products are produced at the same time (see Öner and Bilgic 2008) and each change made at a production stage affects the following phases. Sawing, drying, and finishing operations are typically planned using different models in a decentralized environment. Even though these three activities share the same goal, they may lack coherence because each unit is optimized independently (Gaudreault et al. 2010). This could explain why this industry often suffers from a low order-fill rate, high inventory, and significant lead time. Planning these operations using a centralized approach (based on a single coordinator responsible for establishing a centralized plan that must be followed by the planners of each subsystem) limits the specific operational details that can be taken into account (Gaudreault et al. 2010). Furthermore, Gaudreault et al. (2009) mentioned that centralized approaches cannot be used because of the complexity of the process involved, and highlighted the fact that there are not enough powerful computers able to process this data system. Thus, in order to keep the system decentralized (based on the fact that each unit is responsible for its own planning) while ensuring customer demand satisfaction, the lumber production process may be synchronized using efficient coordination mechanisms. These coordination mechanisms can be tools, agreements, and information that are used to ensure the coordination of the entire production process (Arshinder et al. 2011).This research focuses on the coordination of these production stages in order to increase the volume of sales and decrease the average inventory. A simulation approach inspired from Dumetz et al. (2016) is proposed to simulate the entire softwood sawmilling production process at the operational level and evaluate the use of different coordination mechanisms, based on different order acceptance policies. The planning processes are further simulated by integrating mathematical optimization models for each processing activity.In particular, two coordination mechanisms reported by Gaudreault et al. (2010) as being effective for the sawmilling industry are analyzed. In their original article, the authors evaluated these mechanisms using static data sets, namely a fixed planning horizon as well as a fixed and known demand (that is, a set of orders that is known in advance, before planning) for the whole planning horizon. Two mechanisms were already tested and showed good results in a particular context; therefore, we wanted to evaluate such coordination mechanisms with a more realistic dynamic order arrival process, which calls for periodic production replanning (rolling horizon) as well as the implementation of order acceptance policies (i.e., Available-to-Promise, Capable-to-Promise, and Stock). The environment is then considered to be dynamic because new orders arrive from one week to another and they must be taken into account. Results show that in this dynamic context, using the aforementioned mechanisms leads to poor performance, which may be explained by the high level of coproduction that affects coordination. A hybrid push–pull coordination mechanism, taking into account the decoupling point concept, is therefore proposed and evaluated. Simulation reveals that such a mechanism may lead to a higher order acceptance rate as well as a lower inventory. From an industrial point of view, this study provides information regarding how better coordination can be achieved in a decentralized production system with coproduction.The remainder of this article is organized as follows. “Preliminary Concepts” introduces preliminary concepts about the North American lumber industry and coordination in supply chains and the coordination mechanisms evaluated. “Assessing Coordination Mechanisms in a Dynamic Context” describes the simulation framework needed to carry out the experiments and presents the experiments and the results. Finally, “Conclusions” concludes the article.

Le principe du juste a temps (JAT, en anglais JIT « Just In Time ») consiste a fournir au client le nombre de produits qu’il demande au moment ou il le souhaite, a l’endroit desire et dans le standard de qualite et de couts fixes . Cela implique en premier lieu que l’ensemble de la production soit assujetti a la demande du client (interne ou externe). Dans les faits, ce principe conduit les entreprises a « faire vite pour vendre vite », car les demandes clients sont de plus en plus variees et leurs delais de livraison de plus en plus courts. Des la demande percue, la mise en production, ou tout au moins l’assemblage, doit etre realisee. Par ailleurs, il s’agit aussi de preserver les marges face aux nouvelles formes de concurrence. L’entreprise doit alors chercher a « produire au cout global le plus bas » sans pour autant reduire la qualite de ses produits ou services attendus par ses clients. La seule solution sera alors de « bien faire du premier coup » les specifications edictees par le client et ainsi assurer sa fidelite. Cependant, un regard rapide sur l’histoire nous montre que les hommes ont toujours su produire des « objets de qualite ». Dans le contexte industriel actuel, ce qui nous differencie du passe tient dans la definition meme de la qualite, d’une part, et dans la repetitivite et la vitesse, d’autre part. Ces contraintes conduisent a la generation d’ecarts entre la cible visee et ce qui est effectivement realise. Le probleme est donc de minimiser et de maitriser ces ecarts. Le vecteur essentiel de succes est evidemment l’individu : « rien n’est possible sans les hommes ». Il conviendra alors d’assurer leur participation, leur adhesion aux concepts du JAT et en particulier aux principes qui conduisent a la recherche d’une amelioration continue. Le juste a temps conduit a eliminer tous les gaspillages . Cela signifie que « si vous n’avez pas besoin de quelque chose maintenant, alors ne le faites pas ».

En gestion des stocks, on distingue deux types d’articles : ceux qui font l’objet d’une demande dependante et ceux qui font l’objet d’une demande independante . Une demande est dite dependante si elle peut etre deduite de la demande d’un autre article. Une demande est dite independante dans le cas contraire, c’est-a-dire quand elle est emise par un client : il s’agit typiquement de produits finis et de pieces de rechange. L’exemple le plus simple d’une demande dependante est celui des composants d’un produit fini. La connaissance des nomenclatures et des caracteristiques de fabrication du produit fini permet de deduire les quantites exactes de chacun des composants dont il convient d’assurer la fabrication ou l’approvisionnement (voir article « Flux pousses : MRP et DRP » THOMAS (A.), LAMOURI (S.) - Flux pousses : MRP et DRP. ). De la demande prevue du produit fini, on peut donc deduire la demande de chacun des composants. En theorie, on peut deduire de l’ensemble des demandes independantes les besoins, en nombre et dans le temps, des articles a demande dependante. MRP2 gere les demandes dependantes ; les articles a demande independante sont geres de facon differente et c’est l’objet du present texte . Le decisionnaire en production se trouve en permanence face au dilemme suivant : d’une part, avoir un taux de service client proche de 100 % (ce qui signifie stocker toutes sortes de produits finis a chaque instant) et, d’autre part, se conformer aux obligations de l’analyse financiere qui le conduisent a pousser l’ensemble des acteurs vers une minimisation du niveau des stocks. En fait, si l’on etait capable d’avoir une demande absolument reguliere et, pour le meme volume, si les previsions commerciales etaient toujours « justes » et refletant par anticipation la demande reelle client, on serait alors capable de repondre tres exactement a l’ensemble des besoins. Les stocks perdraient leur raison d’etre. La realite est tout autre : la demande est versatile. Le probleme consiste alors a adapter la capacite de l’outil de production pour permettre de repondre a la somme des besoins. Par voie de consequence, le volume de la production variera en essayant de suivre le rythme des ventes, ce qui conduira inevitablement a la constitution de stocks tout au long de la chaine logistique pour servir de tampon entre ces deux fonctions. Par ailleurs, le quotidien d’un poste de travail est rempli de multiples dysfonctionnements (ralentissement, panne machine, retouche, rebut...). Les stocks deviennent alors l’outil qui permet au gestionnaire de ne pas arreter la production sur les autres postes de charge, l’aidant ainsi a respecter ses objectifs de productivite. L’inconvenient, par contre, est qu’a la lecture des indicateurs de fin de journee ils cachent systematiquement les aleas qui sont survenus. Ils sont donc un frein important a la demarche de progres permanent parce qu’ils empechent de voir l’ensemble des problemes qui surviennent dans le systeme. En allant encore plus en avant dans les « effets en cascade » que les stocks peuvent induire, on pourra citer le fait que plus on a de stock dans le systeme de production, plus on induit sur celui-ci de la lenteur et de l’inertie. On constate que la reduction des stocks permet des economies d’echelle, au-dela de la diminution des immobilisations, en abaissant les couts de production. De plus, si les stocks presentent des avantages de regulation face a toutes les variabilites agissant sur le systeme, ils ont par ailleurs, certains inconvenients comme la rigidification de la production, l’augmentation du delai global moyen ou encore l’immobilisation de moyens financiers (ils representent environ 30 a 40 % des capitaux immobilises). On peut donc dire pour resumer que, si les stocks jouent un role positif de regulation du systeme de production, ils ont plusieurs inconvenients. Le role du gestionnaire en production est donc de trouver un compromis permettant d’obtenir un resultat globalement positif pour un cout minimal. Pour trouver cet optimal, il faut aller plus en avant dans l’analyse des stocks.

Recent advances in Laser Plasma Acceleration techniques (LPA) are now able to generate strong accelerating gradients (GV.m⁻¹); however the produced electron beam thus still presents a large energy spread (%) and a large divergence (mrad). The COXINEL project (ERC Advanced Grant 350014, PI. M.E. Couprie), aims at qualifying, in replacement of a conventional accelerator, a Laser Plasma Accelerator, for a Free Electrons Laser application. To achieve the required properties, the electron beam must be manipulated using a transport line. This line consists in a first triplet of permanent magnets quadrupoles of variable gradient which focuses the beam and allows for the control of the initial divergence. An electromagnetic chicane then reduces the slice energy spread by lengthening the beam longitudinally. A restricted energy range can then be selected by inserting a slit inside the chicane. Finally, a quadruple of electromagnetic quadrupoles provides the final focus in an undulator. The thesis deals on the study of electron beam transport produced by LPA along this line. Different electron production regimes have been used: ionization injection, gas cell. The transport was controlled using a new alignment and pointing compensation method for the initial electron beam by adjusting independently the beam position and dispersion at different location on the line. A fine adjustment of the transported energy was carried out by adjusting the quadrupole gradient. The produced beam was transported along the line and was characterized in terms of transverse distribution, emittance and energy. Experimental results were then successfully compared with numerical simulations. This work paves the way for the observation of undulator radiation, a preliminary step before Free Electron Laser amplification.; Les récents progrès en termes de techniques d’accélération par interaction Laser Plasma (LPA) permettent aujourd’hui de générer de forts gradients accélérateurs (GV.m⁻¹); cependant, les faisceaux d’électrons ainsi produits présentent encore une grande dispersion énergie (%) et une divergence élevée (mrad). Le projet COXINEL (ERC Advanced Grant 350014, PI. M.E. Couprie), vise à qualifier, en remplacement d’un accélérateur conventionnel, un accélérateur Laser Plasma, dans le but d’une application de Laser à Électrons Libres. Pour atteindre les propriétés requises, le faisceau d’électrons doit être manipulé à l’aide d’une ligne de transport. Cette ligne est constituée d’un premier triplet de quadrupôles à aimants permanents de gradient variable qui focalise le faisceau et permet la maîtrise de la divergence initiale. Une chicane électromagnétique réduit ensuite la dispersion en énergie par tranche en allongeant longitudinalement le faisceau. Une gamme d’énergie restreinte peut être ensuite sélectionnée via l’insertion d’une fente dans la chicane. Enfin, un quadruplet de quadrupôles électromagnétiques fournit la focalisation finale dans un onduleur. Le travail de thèse porte sur l’étude du transport des faisceaux d’électrons produit par LPA le long de cette ligne. Différents régimes de production d’électrons ont été utilisés : injection par ionisation, cellule de gaz. La maîtrise du transport a été obtenue à l’aide d’une nouvelle méthode d’alignement et de compensation de dérive de pointé initial des électrons en réglant de manière indépendante la position et la dispersion du faisceau à différents endroits de la ligne. Un réglage fin de l’énergie transportée a été effectué en ajustant le gradient des quadrupôles. Les faisceaux produits ont été transportés le long de la ligne et caractérisés en termes de distribution transverse, d’émittance et d’énergie. Les résultats expérimentaux ont ensuite été comparés avec succès aux simulations numériques. Ce travail ouvre la voie à l’observation de rayonnement de l’onduleur, étape préliminaire à une amplification Laser à Électrons Libres.

International audience; The need of building process industrialization has seed up the use of new Information Technologies to enhance the productivity and quality of building projects. In particular, the use of the Building Information Modeling (BIM) assets and real time follow-up based on the Cyber Physical System paradigm could be a source of valuable data to support planning and monitoring activities throughout the building life cycle. In the context of process industrialization one challenging issue is the transformation of design data into manufacturing data. The main contribution of this paper is the automatic transformation from engineering bills of material (e-BOM) to manufacturing (m-BOM) ones based on routing sheets and resources’ availability status. Illustrated by an actual prefabricated building case study, a methodological approach to dynamically adapt the e-BOM to m-BOM supported by a generic BOM and its implementation architecture are proposed.

International audience; In recent times, the manufacturing processes are faced with many external or internal (the increase of customized product rescheduling , process reliability,..) changes. Therefore, monitoring and quality management activities for these manufacturing processes are difficult. Thus, the managers need more proactive approaches to deal with this variability. In this study, a proactive quality monitoring and control approach based on classifiers to predict defect occurrences and provide optimal values for factors critical to the quality processes is proposed. In a previous work (Noyel et al. 2013), the classification approach had been used in order to improve the quality of a lacquering process at a company plant; the results obtained are promising, but the accuracy of the classification model used needs to be improved. One way to achieve this is to construct a committee of classifiers (referred to as an ensemble) to obtain a better predictive model than its constituent models. However, the selection of the best classification methods and the construction of the final ensemble still poses a challenging issue. In this study, we focus and analyze the impact of the choice of classifier types on the accuracy of the classifier ensemble; in addition, we explore the effects of the selection criterion and fusion process on the ensemble accuracy as well. Several fusion scenarios were tested and compared based on a real-world case. Our results show that using an ensemble classification leads to an increase in the accuracy of the classifier models. Consequently, the monitoring and control of the considered real-world case can be improved.

The ERC Advanced Grant COXINEL aims at demonstrating free electron laser amplification, at a resonant wavelength of 200 nm, based on a laser plasma acceleration source. To achieve the amplification, a 10 m long dedicated transport line was designed to manipulate the beam qualities. It starts with a triplet of permanent magnet with tunable gradient quadrupoles (QUAPEVA) that handles the highly divergent electron beam, a demixing chicane with a slit to reduce the energy spread per slice, and a set of electromagnetic quadrupoles to provide a chromatic focusing in a 2 m long cryogenic undulator. Electrons of energy 176 MeV were successfully transported throughout the line, where the beam positioning and dispersion were controlled efficiently thanks to a specific beam based alignment method, as well as the energy range by varying the slit width. Observations of undulator radiation for different undulator gaps are reported., Proceedings of the 60th ICFA Advanced Beam Dynamics Workshop on Future Light Sources, FLS2018, Shanghai, China

We present the magnetic and the mechanical design of tunable high gradient permanent magnet (PM) quadrupoles. The tunable gradient of the so-called QUAPEVAS extends from 100T/m up to 200T/m. Seven of them with various lengths, ranging from 26mm up to 100mm, for different integrated quadrupole strengths were manufactured. The measured magnetic performance of these devices is also reported. These devices were successfully developed to transport laser plasma accelerated electron beam. Such applications have however less stringent multipole harmonic content constraints than diffraction limited Light sources. Trails for lowering the multipole harmonics will be discussed., Proceedings of the 60th ICFA Advanced Beam Dynamics Workshop on Future Light Sources, FLS2018, Shanghai, China

International audience; One of the primary factors that impact the master production scheduling performance is demand fluctuation, which leads to frequently updated decisions, thereby causing instability. Consequently, global cost deteriorates, and productivity decreases. A reactive approach based on parametric mixed-integer programming is proposed that aims to provide a set of plans such that a compromise between production cost and production stability is ensured. Several stability measures and their corresponding mixed-integer programming model are proposed. An experimental study is performed to highlight the effectiveness of the reactive approach with regard to the proposed performance measures. It is observed that an improvement in stability does not mean a significant increase in the total production cost. Furthermore, the procedure yields a set of plans that in practice would enable flexible management of production.

International audience; Production planning and control and more generally taking a decision in the context of production systems often consider that input information are known, static and predictable. However, uncertainties on data and perturbations are recorded in the genetic of every production system. For instance, it is impossible to know exactly the level of the demand for a product, the availability of resources, etc. Dealing with this issue asks the question of the ability to take robust decisions against uncertainty (off-line) or the ability to be flexible (on-line). This paper proposes to analyze how Product Driven Systems – as reactive systems against unpredicted perturbations – can be part of operational research solution process against perturbations. Moreover, an overview of models and approaches for dealing with uncertainty in Operational Research is given and a first proposition is made for applying these elements into PDS as decision-making-against-perturbations engines.

Part 1: Building Information Modeling; International audience; In order to ensure a reliable building life cycle management, it is es-sential to generate an accurate and up-to-date referential mock-up that will be used for renovation, extension and maintenance. Based on this statement, we carried out, in a previous work, a research study in the sake of reconstructing a 3D CAD model from a point cloud acquired using a Lidar. This point cloud is pro-cessed automatically to detect planes and contours and to generate the 3D CAD model. However, during the life cycle of the project, different actors from differ-ent fields intervene on the building, which creates several communication con-flicts, and this means a loss of time, energy and money. In order to ensure a con-structive collaboration and a simplified data exchange between the different con-tributors in the building, we continued our work to propose, in this paper, an au-tomatic conversion of a point cloud to a 3D BIM file. This conversion induces the passage to the standard IFC format and the integration of a valuable knowledge in it. To do so, an automatic classification of contours into architec-tural elements is proposed. It consists in defining a hierarchical classification rule reproducing the human reasoning for classifying the architectural elements. Then, based on the classified set of polygons, an automatic generation of 3D IFC model is proposed.

Since the laser invention, the advent of X-ray Free Electron Lasers (FEL) half a century later, opens new areas for matter investigation. In parallel, the spectacular development of laser plasma acceleration (LPA) with several GeV beam acceleration in an extremely short distance appears very promising. As a first step, the qualification of the LPA with a FEL application sets a first challenge. Still, energy spread and beam divergence do not meet the state-of-the-art performance of the conventional accelerators and have to be manipulated to fulfill the FEL requirement. We report here on the undulator spontaneous emission measured after a transport manipulation electron beam line, using variable permanent magnet quadrupoles of variable strength for emittance handing and a demixing chicane equipped with a slit for the energy spread. Strategies of control electron beam position and dispersion have been elaborated. The measured undulator radiation provides an insight on the electron beam properties., Proceedings of the 9th Int. Particle Accelerator Conf., IPAC2018, Vancouver, BC, Canada

Nowadays complex control systems are rising and especially hybrid control architectures which are developed to face the manufacturing control challenges that occur with the last industrial revolution and the emerging of industry 4.0. This work presents an application, on a testing platform, of a scheduling algorithm, with multi-criteria objectives, developed for Acta-Mobilier company suffering from high rework rate. This algorithm will inscribe itself in a hybrid control system based on smart entities. The main objective is to validate the contribution of the proposed algorithm in a disturbed environment. The platform, implemented with a multi-agent's system, allows to measure the reliability of the proposed algorithm used on a complex system in the particular case of high rework rate.

Published in Service Orientation in Holonic and Multi-Agent Manufacturing, Borangiu T., Trentesaux D., Thomas A., Cardin O. (eds). Studies in Computational Intelligence, vol 762, pp. 395-406, Springer, Cham; International audience; In order to deploy AGVs in industry, it is mandatory to consider the tradeoff between the smartness and the embeddability. This paper aims to make the manufacturing research community more sensitive about this tradeoff and its consequences. Nowadays, AGVs are widely chosen by manufacturers to implement flexible material-handling systems which are necessary to cover the industrial requirements. However, many issues, presented in this paper, must be tackled to deploy these AGVs. A tradeoff-oriented procedure is proposed by considering these issues in flexible manufacturing system applications. Then, an approach is proposed to illustrate this procedure by providing simulation and experimental results. This approach is also used to roughly describe the smartness/embeddability tradeoff.

Published in Service Orientation in Holonic and Multi-Agent Manufacturing, Borangiu T., Trentesaux D., Thomas A., Cardin O. (eds). Studies in Computational Intelligence, vol 762, p. 127-136, Springer, Cham; International audience; Years ago, advances in electronics led to electronic components such as RFID, capable to identify a product via a unique identification number. This capacity gave rise to PLIM systems (Product LifeCycle Information Systems), which are information systems ensuring the retrieval of product information wherever and whenever during the product’s lifecycle. However, this article shows that such systems are not yet prepared to treat massive data, generated by IoT infrastructure. To solve this issue, situation awareness is a possible answer. In this paper, this notion is detailed and presented via different examples taken from the literature. Yet, the needed tools to support situation awareness in PLIM systems are still lacking, because there are still some scientific and technical challenges to solve. These challenges are detailed in this paper as well.

Published in Service Orientation in Holonic and Multi-Agent Manufacturing, Borangiu T., Trentesaux D., Thomas A., Cardin O. (eds). Studies in Computational Intelligence, vol 762, p. 79-92, Springer, Cham; International audience; Commercial aircrafts use black-box required for crash investigation purposes. While black-box can be easily recovered in crash events on land, the same does not apply to crash events in great deep ocean water. This paper presents a new solution towards solving black-box data loss on ocean crash using a paradigm called communicating materials. The solution is developed through uniformly integrating hundreds of micro sensors nodes in the aircraft structure. The nodes could then construct a Wireless Sensor Network (WSN) inside the aircraft. When a crash is detected by the aircraft system, the black-box data could be stored in all nodes using data storage protocol for WSN. Since nodes are uniformly deployed in the whole aircraft structure, investigators could thus gather preliminary crash causes information from the nodes inside any floated aircraft wreckage in the ocean. This solution was evaluated using Castalia simulator in terms of reliability, storage capacity, and energy efficiency.

In order to ensure an overall efficient production performance, the industrial experiences and research activities have demonstrated the interest of hybrid control systems, which couple a predictive scheduling with a distributed reactive control. In this context, it is commonly accepted that using the multi-agent systems (MAS) paradigm enhances the reactivity to treat disturbances and improves the decision making process of a shop floor. Each agent can have different capabilities (evolution, learning etc.) and the whole system, based on the agent interaction, leads emerging behaviours to dynamically adapt the production schedule. This paper is aimed to develop and simulate a negotiation scenario to deal with disturbed manufacturing processes. The scenario was implemented on the basis of TRACILOGIS test-bed platform. The negotiation protocol consists in setting the best sequential priority based on some performance indicators. This protocol is compared with a purely reactive production mode.

Recent advances in Laser Plasma Acceleration techniques (LPA) are now able to generate strong accelerating gradients (GV.m⁻¹); however the produced electron beam thus still presents a large energy spread (%) and a large divergence (mrad). The COXINEL project (ERC Advanced Grant 350014, PI. M.E. Couprie), aims at qualifying, in replacement of a conventional accelerator, a Laser Plasma Accelerator, for a Free Electrons Laser application. To achieve the required properties, the electron beam must be manipulated using a transport line. This line consists in a first triplet of permanent magnets quadrupoles of variable gradient which focuses the beam and allows for the control of the initial divergence. An electromagnetic chicane then reduces the slice energy spread by lengthening the beam longitudinally. A restricted energy range can then be selected by inserting a slit inside the chicane. Finally, a quadruple of electromagnetic quadrupoles provides the final focus in an undulator. The thesis deals on the study of electron beam transport produced by LPA along this line. Different electron production regimes have been used: ionization injection, gas cell. The transport was controlled using a new alignment and pointing compensation method for the initial electron beam by adjusting independently the beam position and dispersion at different location on the line. A fine adjustment of the transported energy was carried out by adjusting the quadrupole gradient. The produced beam was transported along the line and was characterized in terms of transverse distribution, emittance and energy. Experimental results were then successfully compared with numerical simulations. This work paves the way for the observation of undulator radiation, a preliminary step before Free Electron Laser amplification., Les récents progrès en termes de techniques d’accélération par interaction Laser Plasma (LPA) permettent aujourd’hui de générer de forts gradients accélérateurs (GV.m⁻¹); cependant, les faisceaux d’électrons ainsi produits présentent encore une grande dispersion énergie (%) et une divergence élevée (mrad). Le projet COXINEL (ERC Advanced Grant 350014, PI. M.E. Couprie), vise à qualifier, en remplacement d’un accélérateur conventionnel, un accélérateur Laser Plasma, dans le but d’une application de Laser à Électrons Libres. Pour atteindre les propriétés requises, le faisceau d’électrons doit être manipulé à l’aide d’une ligne de transport. Cette ligne est constituée d’un premier triplet de quadrupôles à aimants permanents de gradient variable qui focalise le faisceau et permet la maîtrise de la divergence initiale. Une chicane électromagnétique réduit ensuite la dispersion en énergie par tranche en allongeant longitudinalement le faisceau. Une gamme d’énergie restreinte peut être ensuite sélectionnée via l’insertion d’une fente dans la chicane. Enfin, un quadruplet de quadrupôles électromagnétiques fournit la focalisation finale dans un onduleur. Le travail de thèse porte sur l’étude du transport des faisceaux d’électrons produit par LPA le long de cette ligne. Différents régimes de production d’électrons ont été utilisés : injection par ionisation, cellule de gaz. La maîtrise du transport a été obtenue à l’aide d’une nouvelle méthode d’alignement et de compensation de dérive de pointé initial des électrons en réglant de manière indépendante la position et la dispersion du faisceau à différents endroits de la ligne. Un réglage fin de l’énergie transportée a été effectué en ajustant le gradient des quadrupôles. Les faisceaux produits ont été transportés le long de la ligne et caractérisés en termes de distribution transverse, d’émittance et d’énergie. Les résultats expérimentaux ont ensuite été comparés avec succès aux simulations numériques. Ce travail ouvre la voie à l’observation de rayonnement de l’onduleur, étape préliminaire à une amplification Laser à Électrons Libres.

International audience; The quality requirement is an important issue for modern companies. Many tools and philosophies have been proposed to monitor quality, including the seven basic tools or the experimental design. However, high quality requirement may lead companies to work near their technological limit capabilities. In this case, classical approaches to monitor quality may be insufficient. That is why on line quality monitoring based on the neural network prediction model has been proposed. Within this philosophy, the dataset is used in order to determine the optimal setting considering the operating point and the product routing. An inverse model approach is proposed here in order to determine directly the optimal setting in order to avoid defects production. A comparison between the use of a classical multi-inputs multi-outputs NN model and a sequence of different multi-inputs single-output NN models is performed. The proposed approach is tested on a real application case.

International audience; A Cryogenic Permanent Magnet Undulator (CMPU) is capable of achieving high brightness radiation at short wavelengths, by taking advantage of the permanent magnets' enhanced performance at low temperature. A CPMU of period 18 mm (U18) that has been built at Synchrotron SOLEIL is used for the COXINEL project to demonstrate Free Electron Laser (FEL) at 200 nm using a laser plasma acceleration source. Another undulator of period 15 mm (U15) is currently being built to replace U18 undulator for FEL demonstration at 40 nm. A new method is also introduced, using SRWE code, to compute the spectra of the large energy spread beam (few percent) taking into account the variation of the Twiss parameters for each energy slice. The construction of U18 undulator and the magnetic measurements needed for optimization, as well as the mechanical design of U15, are presented.

The ERC Advanced Grant COXINEL aims at demonstrating free electron laser (FEL) at 200 nm, based on a laser-plasma accelerator (LPA). To achieve the FEL amplification a transport line was designed to manipulate the beam properties. The 10 m long COXINEL line comprises a first triplet of permanent-magnet variable-strength quadrupoles (QUAPEVA), which handles the large divergence of LPA electrons, a magnetic chicane, which reduces the slice energy spread, and finally a set of electromagnetic quadrupoles, which provides a chromatic focusing in a 2-m undulator. Electrons were successfully transported through the line from LPA with ionization-assisted self-injection (broad energy spectra up to~250 MeV, few-milliradian divergence)., Proceedings of the 38th Int. Free Electron Laser Conf., FEL2017, Santa Fe, NM, USA

International audience; Commercial aircrafts use black box comprising a Flight Data Recorder (FDR) required for crash investigation purposes. While FDR can be easily recovered in crash events on land, the same does not apply to crash events in great deep ocean water. This paper presents a new solution towards solving FDR data recovery using a paradigm called "communicating materials". The solution is developed through uniformly integrating hundreds of tiny sensor nodes in the aircraft structure. The nodes could then construct a Wireless Sensor Network (WSN) inside the aircraft. Thus, the latest FDR data could be stored in the nodes using data storage protocol for WSN. The proposed storage protocol uses the probabilistic-based flooding scheme to forward data to all nodes inside the aircraft structure within the lowest delay. To improve reliability and collision-avoidance of flooding, different complementing corrective measures are used based on neighborhood information. The protocol is evaluated using Castalia/OMNeT++ simulator.

International audience; A new area is coming with communicating materials able to provide diverse functionalities to users all along the product lifecycle, during the design, manufacturing, use and dismantling phases. These materials can track their own evolution all along the product lifetime, gather helpful information and thus allow information continuum at all time and everywhere. Usually, these functionalities are fulfilled via the integration of specific electronic components into the material (wireless sensors nodes, RFID tags). The present paper forms part of this framework in considering that thousands of micro-sensor nodes are integrated into a precast concrete. Data management in the integrated sensor nodes requires Wireless Sensor Network (WSN) protocols development. We recently developed a data storage protocol, called USEE, for communicating materials. To extract this information, we recently developed also a data retrieval protocol, called RaWPG. In this paper, the performances of these protocols are evaluated on the case study of the precast concrete lifecycle management.

International audience; The impacts of using different order acceptance policiesin manufacturing sectors are usually well known and documented in the literature. However, for industries facing divergentprocesses with co-production (i.e. several products produced at the same time from a common raw material),the evaluation, comparison, and selection of policiesare not trivial tasks. This paperproposesa framework to enable this evaluation. Using a simulation model that integrates a custom-builtERP, we compare and evaluate different order acceptance policiesin various market conditions. Experiments are carried outusing a case from the forestproducts industry. Results illustrate how and when different market conditions related to divergent/co-production industries may call for Available-To-Promise (ATP), Capable-To-Promise (CTP),and other known strategies. Especially, we show that advanced order acceptance policies like CTP may generate a better income for certain types of market and, conversely to typical manufacturing industries, ATP performs better than other strategies for a specific demand patterns.

COXINEL experiment aims at demonstrating free electron laser (FEL) amplification with a laser plasma accelerator (LPA). For COXINEL, a dedicated 8 m transport line has been designed and prepared at SOLEIL. We present here LPA beam transport results around 180 MeV through this line. Different electron beam optics were applied., Proceedings of the 8th Int. Particle Accelerator Conf., IPAC2017, Copenhagen, Denmark

A new area is coming with communicating materials which is able to provide diverse functionalities to users all along the product lifecycle. These materials can track their own evolution all along the product lifetime, gather helpful information and thus allow information continuum at all time and everywhere. These functionalities are fulfilled via the integration of thousands of specific electronic components into the product’s material. This paper forms part of this framework in considering that thousands of micro-sensor nodes are integrated into the material. Specific wireless sensor network (WSN) storage protocols were recently proposed for communicating materials, that uniformly replicate information in the integrated nodes. To extract this information during the product lifecycle, a dedicated WSN data retrieval protocol called random walk and pull gossip data retrieval protocol (RaWPG) is presented in this paper. Unlike well-known literature protocols, RaWPG avoids request flooding because all data are uniformly replicated in WSN. With usual protocols, this may lead to high response duplication rate. RaWPG employs three mechanisms. First, the random walk is used as multihop process to forward the request to further nodes. Then, the pull gossip mechanism is added to interrogate the neighbor nodes during each hop. Finally, a mechanism called farthest neighbor selection is added. Only the farthest and most powerful neighbor is selected as next hop for improving the transmission reliability of request and response messages. The performances of the proposed protocol are evaluated based on a case study, and compared to results obtained with classic approaches issued from the literature.

International audience; The amount of data output in our environment is increasing each day, and the development of new technologies constantly redefines how we interact with information. In the context of PLM (Product Lifecycle Management), it is not uncommon to use intelligent products to ensure an information continuum all along the product life cycle (e.g. for traceability purposes). However, it is not that easy to identify what information should be stored on the product. To answer this question, this paper proposes a data dissemination process to select context- sensitive information from the database, that must be stored/replicated on the product (especially if the product is made of "communicating material"). Our approach uses the fuzzy AHP theory for aggregating points of view from different actors. The data dissemination process is then applied on a case study to embed context-sensitive information on a "communicating textile".

International audience; In recent years, some scholars claimed the usage of intelligent products to make systems more efficient throughout the Product Life Cycle (PLC). Integrating intelligence and information into products themselves is possible with, among others, auto-ID technologies (barcode, RFID,...). In this paper, a new kind of intelligent product is introduced, referred to as "communicating material" paradigm. Through this paradigm, a product is i) capable of embedding information on all or parts of the material that it is made of, ii) capable of undergoing physical transformations without losing its communication ability and the data that is stored on it. This new material is used in our study to convey information between the different actors of the PLC, thus improving data interoperability, availability and sustainability. Although "communicating materials" provide new abilities compared to conventional products, they still have low memory capacities compared to product databases that become larger and larger. An information dissemination framework is developed in this paper to select the appropriate information to be stored on the product, at different stages of the PLC. This appropriateness is based on a degree of data relevance, which is computed by taking into account the context of use of the product (actor's expectations, environment,...). This framework also provides the tools to split information on all or parts of the material. A case study is presented, which aims at embedding context-sensitive information on "communicating textiles".

International audience; Simulation is a useful tool for the evaluation of a Master Production/Distribution Schedule (MPS). The goal of this paper is to propose a new approach to designing a simulation model by reducing its complexity. According to the theory of constraints, a reduced model is built using bottlenecks and a neural network exclusively. This paper focuses on one step of the network model design: determining the structure of the network. This task may be performed by using the constructive or pruning approaches. The main contribution of this paper is twofold; it first proposes a new pruning algorithm based on an analysis of the variance of the sensitivity of all parameters of the network and then uses this algorithm to reduce the simulation model of a sawmill supply chain. In the first step, the proposed pruning algorithm is tested with two simulation examples and compared with three classical pruning algorithms fromthe literature. In the second step, these four algorithms are used to determine the optimal structure of the network used for the complexity-reduction design procedure of the simulation model of a sawmill supply chain.

International audience; Product quality level is become a key factor for companies' competitiveness. A lot of time and money are required to ensure and guaranty it. Besides, motivated by the need of traceability, collecting production data is now commonplace in most companies. Our paper aims to show that we can ensure the required quality thanks to an "on-line quality approch" and proposes a neural network based process to determine the optimal setting for production machines. We will illustrate this with the Acta-Mobilier case, which is a high quality lacquerer company.

Manufacturing planning and control systems (MPCS) incorporate processes that consider several levels of product aggregation and different time horizons for decision making. The decisions rendered on each level do not always have similar objectives. In the context of intelligent manufacturing systems (IMS), the coordination of decisions on different levels is a fundamental problem. Extensive research on IMS, specifically regarding coordination among decision levels in product-driven control systems (PDCS), is nonexistent. Therefore, simulations of the planning and control processes are proposed to analyze the coordination of multilevel objectives. The proposed implementation simulates the coordination between tactical and operational levels. At the tactical level, production plans are obtained through a system based on advanced planning and scheduling (APS). At the operational level, a decentralized system, which is based on distributed decision rules, is implemented. The simulation considers decentralized decisions that are managed by production lots, which are modeled as holons, and based on an industrial study case. The results indicate that coordination is feasible and highlight the importance of the reactivity caused by the distributed decisions made by the active lots. The proposed simulation schema can also be used to compare conventional and holonic collaborative approaches.