88 research outputs found
Environnement de simulation GDEVS compatible HLA
National audienceDeux des enjeux actuels de la simulation sont la réutilisation de modÚles et la composition de simulations globales distribuées à partir de simulateurs répartis. Cette publication présente un environnement contribuant à modéliser et simuler de façon distribuée un systÚme. Cet environnement utilise les concepts de spécification DEVS développés par B.P. Zeigler et la généralisation GDEVS définie par N. Giambiasi permettant ainsi d'utiliser les performances de la simulation à événements discrets. Il permet également la composition de modÚles à partir d'éléments stockés en bibliothÚques, évitant le redéveloppement de simulations existantes. De plus, la structure de simulation choisie est « mise à plat », réduisant ainsi l'échange de messages entre les composants par rapport à la structure des simulateurs DEVS existants. Enfin, sa compatibilité avec la norme HLA, grùce à l'utilisation de mécanismes de synchronisation d'échange des messages, lui permet de s'intégrer dans des simulations globales hétérogÚnes compatibles HLA
Product-service systems scenarios simulation based on G-DEVS/HLA: Generalized discrete event specification/high level architecture
International audienceIn the past decade, personal customers expected manufacturing companies to provide them with a physical product with, nonetheless, some basic additional services. Currently, customers expect a more comprehensive solution, integrating both a physical product and non-physical services, which explains why companies have started to propose Product-Service Systems (PSS). The underlying objective of profitability can be attained if the system is designed, based on system use, to avoid waste, and if services are developed jointly with products. Although all the requisite conditions are well-known, the optimal way to satisfy them is not formalized or even guided by any clear methodology. This paper proposes to create PSS models to be simulated in different service scenarios based on G-DEVS/HLA. The simulation results provide pointers to help decision maker choose between several PSS design scenarios to be manufactured. A case study from the toy industry is used to illustrate the proposed methodology
UN ENVIRONNEMENT G-DEVS/HLA :<br />APPLICATION A LA MODELISATION ET SIMULATION DISTRIBUEE DE WORKFLOW
The researches of this thesis are divided in:â the proposition of conservative distributed simulation algorithms of models DEVS / G-DEVS,â the definition and the realization of a G-DEVS modeling and simulation (M&S) environment HLA compliant implementing the proposed algorithms,â the application of the environment in the M&S of Workflow.First, we introduced a G-DEVS distributed root coordinator component, including an algorithm of commu-nication with the RTI HLA based on the mechanism of conservative synchronization and using positive Looka-head. Then, we proposed two original algorithms for the computation of Lookahead concerning the current state of a G-DEVS model. These algorithms, based on the analysis of the variation domain of the âlifetimeâ function of the model, increase the performances of the distributed simulation as the led experiments illustrate it.Based on these approaches, we developed a distributed G-DEVS / HLA M&S environment. This environ-ment was integrated into an application of Workflow. The possibilities offered by the environment were illus-trated by the study of company's real cases of Workflow.Les travaux de cette thĂšse portent sur :â la proposition d'algorithmes de simulation distribuĂ©e conservative de modĂšles DEVS / G-DEVS,â la dĂ©finition et la rĂ©alisation d'un environnement de modĂ©lisation & simulation (M&S) G-DEVS com-patible HLA implĂ©mentant les algorithmes proposĂ©s,â l'application de l'environnement Ă la M&S de Workflow.Dans un premier temps, nous avons introduit un composant coordinateur racine G-DEVS distribuĂ©, incluant un algorithme de communication avec le RTI HLA basĂ© sur le mĂ©canisme de synchronisation conservative et utilisant un Lookahead positif. Nous avons ensuite proposĂ© deux algorithmes originaux pour le calcul d'un Loo-kahead relatif Ă l'Ă©tat courant d'un modĂšle G-DEVS. Ces algorithmes, basĂ©s sur l'analyse du domaine de varia-tion de la fonction « durĂ©e de vie » du modĂšle, augmentent les performances de la simulation distribuĂ©e comme l'illustrent les expĂ©riences menĂ©es.BasĂ© sur ces approches, nous avons dĂ©veloppĂ© un environnement de M&S distribuĂ© G-DEVS / HLA. Cet environnement a Ă©tĂ© intĂ©grĂ© Ă une application de Workflow. Les possibilitĂ©s offertes par l'environnement ont Ă©tĂ© illustrĂ©es par l'Ă©tude de cas rĂ©els d'entreprises
Unified Reversible Life Cycle for Future Interoperable Enterprise Distributed Information Systems
Best Paper AwardInternational audienceThis paper aims at improving the re-implementation of existing information systems when they are called to be involved in a system of systems, i.e. a federation of enterprise information systems that interoperate. The idea is reusing the local experiences coming from the development of the original information system with the process of Model Discovery and Ontological approach. We give first, a review of ongoing researches on Enterprise Interoperability. The MDA can help to transform concepts and models from the conceptual level to the implementation. The HLA standard, initially designed for military M&S purpose, can be transposed for enterprise interoperability at the implementation level, reusing the years of experiences in distributed systems. From these postulates, we propose a MDA/HLA lifecycle to implement distributed enterprise models from the conceptual level of federated enterprise interoperability approach. In addition to this classical development, we propose a model reversal methodology to help re-implement the legacy information system, in order to achieve the interoperability with other systems
Building a high-level architecture federated interoperable framework from legacy information systems
International audienceThis paper aims at improving the re-implementation of existing information systems when they are called to be involved in a system of systems, i.e. a federation of enterprise information systems that interoperate. The idea is reusing the local experiences coming from the previous development of the existing information system with the process of model discovery. To avoid redeveloping the entire system when the enterprise needs to cooperate with others, this approach proposes to create local interfaces to code and decode information. The interfaces are instantiated by using models discovered. The interfaces are developed in accordance with the high-level architecture (HLA) standard that proposes message interoperability and synchronisation mechanisms among distributed systems. First, this paper recalls the strong points of model-driven architecture (MDA)/architecture-driven modernisation methodologies for model transformation from conceptual level to implementation and the HLA standard. Then, a MDA and HLA framework is proposed to implement distributed enterprise components from the conceptual level through a federated enterprise interoperability approach. In addition, a model reversal methodology is developed under the framework to guide the re-implementation of legacy information systems to achieve desired interoperability with other systems. To extend the scope of the approach, implemented Web services are combined with HLA in order to facilitate the use of HLA in large distributed execution. This paper ends with an implementation example for validating the approach
Lookahead Computation in G-DEVS/HLA Environment
International audienceIn this article, we present new methods to evaluate lookahead of DEVS/G-DEVS federates participating in a HLA federation. We propose first an algorithm to compute the lookahead according to the current state of a DEVS/G-DEVS model. This solution is designed for models with lifetime function depending on one state variable. Then, we extend this computation to models with lifetime functions defined with several state variables. We use the Dijkstra graph theory search to compute the different values of state variables and a mathematical function analysis to determine the lookahead for the model states. Finally, we illustrate with an example how this solution extends the range of DEVS/G-DEVS models that can be involved into distributed simulations and we present some simulation results
A Harmonized and Reversible Development Framework for HLA-Based Interoperable Application
International audienceEnterprise collaboration is becoming more and more important because of the globalized economic context. The competitiveness of enterprises depends not only on their internal productivity and performance, but also on their ability to collaborate with others. This necessity leads to the development of interoperability, which makes it possible to improve collaborations between enterprises. Therefore, more and more networked enterprises are being developed. Further, enterprise interoperability is one of the most suitable solutions to total enterprise integration
SMACKDOWN: Adventures in Simulation Standards and Interoperability
International audienceThe paucity of existing employer-driven simulation education and the need for workers broadly trained in Modeling & Simulation (M&S) poses a critical need that the simulation community as a whole must ad-dress. This paper will describe how this need became an impetus for a new inter-university activity that allows students to learn about simulation by doing it. The event, called Smackdown, was demonstrated for the first time in April at the Spring Simulation Multi-conference. Smackdown is an adventure in in-ternational cooperation. Students and faculty took part from the US and Europe supported by IEEE/SISO standards, industry software and National Aeronautics and Space Administration (NASA) content of a re-supply mission to the Moon. The developers see Smackdown providing all participants with a memora-ble, interactive, problem-solving experience, which can contribute, importantly to the workforce of the fu-ture. This is part of the larger need to increase undergraduate education in simulation and could be a prime candidate for senior design projects
Environnement G-DEVS/HLA pour la simulation distribuée de systÚmes de production multiprocessus
International audienceThis paper presents a simulation environment for manufacturing systems integrating control processes and operational processes. From the operational processes specification according to the JIS Z 8206 norm and from the control processes as Workflows standards, distributed G-DEVS models are generated. At first, the transformation of a process in G-DEVS models is described. Then, the implementation of a global simulation of the set of these models via an HLA architecture allowing interconnection and interoperability between the model components is presented. An illustration of the use of this environment is given in the microelectronic field. We conclude by the application of this approach to the study of the synchronizations between production lines and to the implementation of coupling between simulation and reality
ModĂšle dâanalyse de la valeur de lâinnovation des systĂšmes de produit-service
RĂ©sumĂ© â LâĂ©conomie traditionnelle basĂ©e sur la vente dâun produit Ă un client est actuellement remise en question par lâintĂ©rĂȘt grandissant de ce dernier pour la valeur dâusage du produit au-delĂ de sa valeur dâĂ©change. En consĂ©quence, les industriels doivent dorĂ©navant considĂ©rer la satisfaction dâun besoin par la proposition dâun couple produit et service (PSS). Le traitement simultanĂ© de ces deux enjeux permettra d'amĂ©liorer la position dans la chaĂźne de valeur, dâaccroĂźtre la valeur ajoutĂ©e de lâoffre et d'amĂ©liorer le potentiel d'innovation de lâentreprise productrice de la solution PSS. Le challenge se situe donc dans lâoptimisation du ratio valeur dâusage/prix de lâoffre PSS pour le client et Ă©galement pour lâindustriel. Nous proposons dans cette contribution les prĂ©mices dâun modĂšle dâanalyse de la valeur de lâinnovation des systĂšmes de produits et services. Nous avons pour cela identifiĂ© les fonctions attendues dâun PSS pour le client et celles attendues par le fournisseur de la solution. Ces fonctions rapportĂ©es au coĂ»t global du systĂšme permettent de dĂ©terminer la valeur de lâoffre pour les protagonistes et dâaider Ă la dĂ©cision du dĂ©veloppement effectif de lâoffre. Abstract - The traditional economy based on selling products to clients is currently challenged by the growing user interest for the product use value than the product exchange value. Consequences for manufacturers are significant because they must now extend their skills to the fulfillment of a need through the delivery of an integrated set of products and services (PSS). The added service will improve the position in the value chain of the product, increase the added value of the offer and improve the innovation potential. These benefits of the PSS can be obtained considering the global design collaboration and the engineering work necessary to design and deliver PSS. The challenge therefore lies in optimizing the ratio value of use to cost of the PSS for the user as well as for the industry. We propose in this article the foundation of a model for analyzing the value of a PSS innovation. The model is built upon the list of function expected by the user and those expected by the provider of the system. Each list related to the system whole costs will give an idea of the value of the offer for each stakeholder and aggregating the value an aid to decide whether the development is to be launched or not
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