Un développement d'un système débute par la constitution, dans la phase de spécification des besoins, d'un cahier des charges dans lequel un ensemble de scénarios d'utilisation du système est défini avec les contraintes auxquelles il doit obéir, dans lequel chaque scénario est un simple exemple d'exécution du système à concevoir. Une fois que tous les scénarios sont précisés, on obtient une description complète des interactions entre les composants. Toutefois, cette spécification n'est pas directement implémentable, car il est difficile, surtout pour les systèmes les plus complexes, d'apercevoir le comportement d'un système dans sa globalité directement à partir des scénarios. C'est pour cela que ces derniers sont souvent intégrés à d'autres modèles, utilisés dans la conception détaillée, qu'on appelle "les modèles de comportement", en particulier les machines à états [Harel 87] qui permettent de passer de la vue partielle à la vue globale du système afin de répondre à différents problèmes comme la validation du comportement ou la détection des inconsistances au sein du système. Notre thèse a pour but, d'une part, de recenser et étudier différents langages de scénarios, particulièrement les diagrammes de séquences UML et les diagrammes MSC's, et d'autre part de proposer une méthode se synthèse automatique permettant de générer des modèles exécutables à évènements discrets DEVS [Zeigler 76] à partir d'une base de scénarios décrivant le comportement fonctionnel du système. Les modèles obtenus sont déterministes et avec une sémantique formelle qui garantit une interprétation unique de chaque élément des modèles. / A development of a system begins with the constitution, in the phase of requirements analysis, a specification in which a set of scenarios describing the behavior of the system is defined with the constraints that it must obey, where each scenario is a partial representation of the system behavior. However, this specification is not directly implementable, because it is difficult, especially for more complex systems, to observe the global behavior of a system directly from scenario. That is why they are often integrated with other models used in the detailed design, called "behavioral models", in particular State Machines [Harel 87], who allow to move from partial to global view of the system in order to answer different problems such as validation of the behavior or the detection of system inconsistencies. Our thesis aims, firstly, to study different languages of scenarios, especially UML sequence diagrams, and MSC's (Message Sequence Charts), and secondly to propose an automatic synthesis method who generate executable discrete event DEVS models [Zeigler 76] from scenarios describing the desired behavior of a system. The resulting models are executable and deterministic with a formal semantics that ensures a unique interpretation of each element of models. The use of final models simulation traces, taking into account the coverage of the simulation compared to the number of states and transitions visited, allow validating the behavior.

L'étude présentée dans ce mémoire concerne le diagnostic des machines électriques à l'aide d'une association innovante entre la modélisation à évènements discrets, la Simulation Comparative et Concurrente (SCC) et les Réseaux de Neurones Artificiels (RNAs). Le diagnostic des machines électriques est effectué à partir d'une analyse temporelle des signaux statoriques et rotoriques à l'aide de réseaux de neurones de type Feed-Forward. Afin de comparer les différentes configurations de ces réseaux de neurones, l'approche proposée dans ce document utilise la simulation comparative et concurrente implémentée grâce au formalisme à évènements discrets DEVS (Discrete EVent system Specification). L'intégration des algorithmes de la SCC et des RNAs au sein du formalisme DEVS a été effectuée de manière générique et indépendamment du simulateur en développent des extensions et une librairie de modèles dans l'environnement de modélisation et de simulation à évènements discrets DEVSimPy. L'application de cette nouvelle solution pour le diagnostic des machines électriques permet de détecter les défauts à partir d'une architecture logiciel facilement portable sur des systèmes embarqués de type FPGA. / This thesis deals with the time-domain analysis of the electrical machines fault diagnosis due to early short-circuits detection in both stator and rotor windings. It also introduces to the Discrete EVent system Specification (DEVS) a generic solution to enable concurrent and comparative simulations (CCS). The DEVS-based CCS is an extension introduced using an aspect-oriented programming (AOP) to interact with the classic DEVS simulator. A new DEVS-based artificial neural network (ANN) is also introduced with a separation between learning and calculation models. The DEVS-based CCS is validated on the proposed ANN DEVS library inside the DEVSimPy environment. The concurrent ANN contributes in the time-domains analysis for the electrical machine fault diagnosis. This new method is based on data coming directly from the sensors without any computation but with a new dedicated preprocessing technique. Later, some enhancements are brought to the artificial neural network based on a new multistage architecture reducing the training time and errors compared to the single ANN. The new architecture and techniques has been validated on real data sixteen non-destructive windings faults analysis and localization.

Cette thèse se situe dans le contexte de l’importante mutation stratégique qu’opère l’Industrie européenne face à l’émergence de nouveaux Marchés. Une caractéristique majeure de ces nouveaux Marchés est la grande variabilité des besoins clients. Cette mutation remplace le produit manufacturé, au coeur des stratégies Métier, par ses services d’accompagnement, en réponse aux nouvelles exigences des clients. Ainsi, les processus Métier, initialement pensés,construits et pilotés autour du produit, doivent aujourd’hui être revus et complétés de manière à intégrer les services. C’est cette question que veut traiter la thèse, à travers une proposition d’architecture d’ingénierie des services dirigée par les modèles, supportée par un environnement logiciel appelé SLMToolBox qui permet la semi automatisation d’une partie de la gestion du cycle de vie d’un service (modélisation, simulation et évaluation de performances). Ce travail de recherche était dans le cadre de projet MSEE, un projet européen de recherche et développement en collaboration avec 18 partenaires de 9 pays européen. Le but de ce projet est de faire évoluer le concept de SSME (Service Science Management and Engineering) vers des systèmes de production et des usines du futur, i.e. d'un point de vue méthodologique, pour adapter, modifier et étendre les concepts de SSME pour les rendre applicables à des entreprises traditionnellement orientées vers une production orientée produit et d'un point de vue implantation, d'instancier les architectures et les plateformes orientées vers les services liés au futur internet pour des systèmes globaux de production de services.La thèse à apporter plusieurs résultats (MDSEA, Etended Actigram Star EA*, Transformation de modèle, simulation, et SLMToolBox) pour répondre aux besoins de servitization. / In today’s world of business, manufacturers are facing many challenges. Business strategiesivare changing and manufacturers are entering new markets and striving to meet new andchanging customer needs. Manufacturers are outsourcing more components and services tosuppliers around the world, restructuring their internal operating and information systems, andre-engineering production processes to eliminate waste and lower costs. They are changingthe nature of their organizations by partnering with other companies in complex supply chainsand business networks that now extend globally. Manufacturing is being redefined by changesin market place and how companies react to them. As a result, many manufacturers wanted tomake the shift to services as a solution, but they find themselves trapped in the world ofproducts. At the end of the nineties, the concept of Service in Manufacturing appeared and theevolution from an economy of products towards an economy of services surrounding productsbecame more and more important in manufacturing. The process of creating value by addingservices to a tangible product has first been called “servitization”. Based on the problematic ofServitization and service system engineering and in order to reduce effort and time in servicesystem engineering, this thesis (as being part of the MSEE project) contributed in thedevelopment of solutions. The contribution of the thesis’s result can be classified into relatedand connected pillars. The first pillar is the participation in the development of the ModelDriven Service Engineering Architecture (MDSEA) which permits Virtual ManufacturingEnterprises (VME) to model their service systems (AS-IS and TO-BE models) starting frommodeling the system from business experts angle and then adding more details to reach thedevelopers and technical experts angle. The second pillar is the development of a modelingand simulation tool, the SLMToolBox. This tool is a partial implementation of MDSEA andits name Service Lifecycle Management ToolBox implies a role in the service’s lifecycle. Thethird pillar is the development of a DEVS graphical editor and simulator integrated in theSLMToolBox.

L’étude des phénomènes de la diffusion d’information à grand échelle est un domaine récent. La diffusion d’information est définie comme le processus de communication par lequel une idée ou une information se propage dans une population et qui peut impacter le comportement des individus. Les institutions, tout comme les entreprises, cherchent à comprendre et à prévoir l’impact de la propagation d’information sur les individus. Une approche de modélisation et simulation permet de mieux comprendre ce processus social et de répondre à ces questions. La modélisation et la simulation à base d’agents offre une approche puissante pour modéliser un tel processus social. Toutefois, les modèles actuels simplifient fortement les facteurs culturels et les informations représentées dans le modèle ainsi que les différents liens interconnectant les individus. Ces éléments sont centraux et déterminants pour le processus de propagation. Afin d'améliorer les modèles de propagation, nous explorons dans cette thèse une représentation de la population plus réaliste. Nous proposons une architecture de modélisation et simulation permettant de simuler les phénomènes de propagation au sein des réseaux sociaux multiplexes et dynamiques basée sur le formalisme DEVS. / The study of information dissemination phenomena of large-scale is a new field. Diffusion of information is defined as the communication process by which an idea or information spreads within a social system and that can impact the behaviour of individuals. Institutions and firms search to understand and predict the impact of information propagation on individuals. Agent-based modelling is a powerful approach for studying such a collective process. However, existing models oversimplify adopters' cultural attributes, different type of link and information content, despite the evidence of their central role in diffusion process. In this thesis, we challenge the feasibility and utility of a more realistic representation of population. We use the DEVS formalism, extended by DS-DEVS and PDEVS in order to simulate the propagation phenomena within a multi-layer social network (MSN).

Cette thèse propose une approche d’ingénierie consistant à paralléliser des simulateurs DEVS existants, sans être obligé de modifier les algorithmes de l’implémentation initiale, mais en injectant des composants additionnels adaptés au protocole de communication intercomposants en vigueur. Les algorithmes de simulation de ces nouveaux composants appelés « Manteaux », sont définis. Une démarche d’ingénierie permettant de systématiser le passage d’une implémentation à sa contrepartie parallèle et distribuée est ensuite proposée. Cette démarche s’appuie sur les principes de méta modélisation et de transformation de modèles inspirés de l’Ingénierie Dirigée par les Modèles (IDM). Sa généricité en garantit la réutilisabilité avec tout simulateur séquentiel DEVS. / This thesis proposes an engineering approach to parallelize existing DEVS simulators without having to modify the algorithms of the initial implementation, but by injecting additional components suitable for inter-component communication protocol into force. The simulation algorithms of these new components called "Coats" are defined.An engineering approach to systematize the passage from one implementation to its counterpart parallel and distributed is then proposed. This approach is based on metamodeling and models transformation principles inspired of Model Driven Engineering (MDE). Its genericity guarantees the reusability with any sequential DEVS simulator.

Wildfires have significant impact on both ecosystems and human society. To effectively manage wildfires, simulation models are used to study and predict wildfire spread. The accuracy of wildfire spread simulations depends on many factors, including GIS data, fuel data, weather data, and high-fidelity wildfire behavior models. Unfortunately, due to the dynamic and complex nature of wildfire, it is impractical to obtain all these data with no error. Therefore, predictions from the simulation model will be different from what it is in a real wildfire. Without assimilating data from the real wildfire and dynamically adjusting the simulation, the difference between the simulation and the real wildfire is very likely to continuously grow. With the development of sensor technologies and the advance of computer infrastructure, dynamic data driven application systems (DDDAS) have become an active research area in recent years. In a DDDAS, data obtained from wireless sensors is fed into the simulation model to make predictions of the real system. This dynamic input is treated as the measurement to evaluate the output and adjust the states of the model, thus to improve simulation results. To improve the accuracy of wildfire spread simulations, we apply the concept of DDDAS to wildfire spread simulation by dynamically assimilating sensor data from real wildfires into the simulation model. The assimilation system relates the system model and the observation data of the true state, and uses analysis approaches to obtain state estimations. We employ Sequential Monte Carlo (SMC) methods (also called particle filters) to carry out data assimilation in this work. Based on the structure of DDDAS, this dissertation presents the data assimilation system and data assimilation results in wildfire spread simulations. We carry out sensitivity analysis for different densities, frequencies, and qualities of sensor data, and quantify the effectiveness of SMC methods based on different measurement metrics. Furthermore, to improve simulation results, the image-morphing technique is introduced into the DDDAS for wildfire spread simulation.

Simulation software is being increasingly used in various domains for system analysis and/or behavior prediction. Traditionally, researchers and field experts need to have access to the computers that host the simulation software to do simulation experiments. With recent advances in cloud computing and Software as a Service (SaaS), a new paradigm is emerging where simulation software is used as services that are composed with others and dynamically influence each other for service-oriented simulation experiment on the Internet. The new service-oriented paradigm brings new research challenges in composing multiple simulation services in a meaningful and correct way for simulation experiments. To systematically support simulation software as a service (SimSaaS) and service-oriented simulation experiment, we propose a layered framework that includes five layers: an infrastructure layer, a simulation execution engine layer, a simulation service layer, a simulation experiment layer and finally a graphical user interface layer. Within this layered framework, we provide a specification for both simulation experiment and the involved individual simulation services. Such a formal specification is useful in order to support systematic compositions of simulation services as well as automatic deployment of composed services for carrying out simulation experiments. Built on this specification, we identify the issue of mismatch of time granularity and event granularity in composing simulation services at the pragmatic level, and develop four types of granularity handling agents to be associated with the couplings between services. The ultimate goal is to achieve standard and automated approaches for simulation service composition in the emerging service-oriented computing environment. Finally, to achieve more efficient service-oriented simulation, we develop a profile-based partitioning method that exploits a system’s dynamic behavior and uses it as a profile to guide the spatial partitioning for more efficient parallel simulation. We develop the work in this dissertation within the application context of wildfire spread simulation, and demonstrate the effectiveness of our work based on this application.

Simulation software is being increasingly used in various domains for system analysis and/or behavior prediction. Traditionally, researchers and field experts need to have access to the computers that host the simulation software to do simulation experiments. With recent advances in cloud computing and Software as a Service (SaaS), a new paradigm is emerging where simulation software is used as services that are composed with others and dynamically influence each other for service-oriented simulation experiment on the Internet. The new service-oriented paradigm brings new research challenges in composing multiple simulation services in a meaningful and correct way for simulation experiments. To systematically support simulation software as a service (SimSaaS) and service-oriented simulation experiment, we propose a layered framework that includes five layers: an infrastructure layer, a simulation execution engine layer, a simulation service layer, a simulation experiment layer and finally a graphical user interface layer. Within this layered framework, we provide a specification for both simulation experiment and the involved individual simulation services. Such a formal specification is useful in order to support systematic compositions of simulation services as well as automatic deployment of composed services for carrying out simulation experiments. Built on this specification, we identify the issue of mismatch of time granularity and event granularity in composing simulation services at the pragmatic level, and develop four types of granularity handling agents to be associated with the couplings between services. The ultimate goal is to achieve standard and automated approaches for simulation service composition in the emerging service-oriented computing environment. Finally, to achieve more efficient service-oriented simulation, we develop a profile-based partitioning method that exploits a system’s dynamic behavior and uses it as a profile to guide the spatial partitioning for more efficient parallel simulation. We develop the work in this dissertation within the application context of wildfire spread simulation, and demonstrate the effectiveness of our work based on this application.

In this thesis, we present our approach to add dynamism support to simulation environments, which adopts DEVS-based modeling and simulation approach and builds upon previous work on SiMA, a DEVS-based simulation framework developed at TUBITAK UEKAE. Defining and executing simulation models of complex and adaptive systems is often a non-trivial task. One of the requirements of simulation software frameworks for such complex and adaptive systems is that supporting variable structure models, which can change their behavior and structure according to the changing conditions. In the relevant literature there are already proposed solutions to the dynamism support problem. One particular contribution offered in this study over previous approaches is the systematic and automatic framework support for poststructural-change state synchronization among models with related couplings, in a way that benefits from the strongly-typed execution environment SiMA provides. In this study, in addition to introducing theoretical extensions to classic SiMA, performance comparisons of dynamic version with classic version over a sample Wireless Sensor Network simulation is provided and possible effects of dynamism extensions to the performance are discussed.

abstract: Time-series plots are used in many scientific and engineering applications. In this thesis, two new plug-ins for piecewise constant and event time-series are developed within the Eclipse BIRT (Business Intelligence and Reporting Tools) framework. These customizable plug-ins support superdense time, which is required for plotting the dynamics of Parallel DEVS models. These plug-ins are designed to receive time-based alphanumerical data sets from external computing sources, which can then be dynamically plotted. Static and dynamic time-series plotting are demonstrated in two settings. First, as standalone plug-ins, they can be used to create static plots, which can then be included in BIRT reports. Second, the plug-ins are integrated into the DEVS-Suite simulator where runtime simulated data generated from model components are dynamically plotted. Visual representation of data sets can simplify and improve model verification and simulation validation. / Dissertation/Thesis / Masters Thesis Computer Science 2015