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This work describes a design of an agent model for robotic soccer based on the DEVS formalism. There is also presented a design of own DEVS simulator (based on classic DEVS simulator) for parallel realtime simulations. Functionality of the simulator and the model is shown on an example of a soccer client for RoboCup Soccer Server. Based on this client, there is also presented a design of a library for easier creation of soccer clients for RoboCup.

Cette thèse s’inscrit au carrefour du monde de la modélisation et simulation de systèmes d’une part et du monde de l’ingénierie logicielle d’autre part. Elle vise à faire bénéficier un formalisme de spécification de systèmes à évènements discrets (DEVS) des apports de l’ingénierie dirigée par les modèles (IDM) avec l’une de ses incarnations les plus populaires : MDA (Model Driven Architecture). Le formalisme DEVS de par son adaptabilité et son extensibilité permet l’expression et la simulation de modèles dans des domaines très variés, mais l’existence de plusieurs plateformes dédiées à ce langage nuit fortement à l’interopérabilité de ces modèles. Ces difficultés, si elles ne sont pas nouvelles, représentent cependant un défi d’autant plus important que les modèles considérés sont complexes (i.e composés en général de nombreux sous modèles et interagissant fortement entre eux). L’objectif de la thèse est de proposer une réponse à la problématique de l’interopérabilité des modèles DEVS, vis-À-Vis d’autres formalismes voisins de DEVS et également vis-À-Vis des différents simulateurs existants. Le cœur de notre travail est constitué par MetaDEVS, méta-Modèle offrant une représentation des modèles DEVS indépendante des plateformes. MetaDEVS est également le nom donné à l’approche globale qui vise à fournir des passerelles génériques entre différents formalismes et DEVS («Model-To-Model»). Cette approche montre également comment, à partir de modèles DEVS spécifiés selon MetaDEVS, du code orienté-Objet, simulable, peut être automatiquement généré («Model-To-Text»).Les formalismes choisis pour faire l’objet d’une transformation vers DEVS sont BasicDEVS, un petit formalisme pédagogique créé pour l’occasion, ainsi que les automates à états finis (FSM). La plateforme de destination choisie pour la génération de code est la plateforme éducative PyDEVS, compatible avec la plateforme DEVSimPy, utilisée par les chercheurs du projet TIC de l’Università di Corsica. / This thesis takes place at the intersection between the world of modeling and simulation, and the world of software engineering. Its provides a contribution to a discrete-Event specification formalism (DEVS) using techniques of Model-Driven Engineering, with one of its most popular incarnations : MDA (Model Driven Architecture). The DEVS formalism, thanks to its adaptability and its extensibility, is able to express and simulate models in various domains. However, the existence of many dedicated platforms damages the interoperability of those models. Those difficulties, even if they are not new, are a challenge which is all the greater as the studied models are complex (i.e. usually composed of several submodels with a strong interaction).The main purpose of this thesis is to tackle the problem of the DEVS models interoperability, with respect to other formalisms close to DEVS, and also with respect to the different existing simulators. The core of our work is constituted by MetaDEVS, a metamodel that offers a platform-Independent representation of DEVS models. MetaDEVS is also the name given to the global approach which aims to provide generic bridges between different formalisms and DEVS (“Model-To-Model”). This approach also shows how, starting from DEVS models specified with MetaDEVS, object-Oriented code can be automatically generated (“Model-To-Text”).The formalisms chosen to be transformed into DEVS are BasicDEVS, a small pedagogical formalism create for our needs, and the finite state machines (FSM). The chosen target platform for the code generation is the educative framework PyDEVS, compliant with the DEVSimPy framework used by the researchers of the TIC project of the University of Corsica.

Recent research advances in Discrete EVent system Specification (DEVS) as well as cellular space modeling emphasized the need for high performance modeling methodologies and environments. The growing demand for cellular space models has directed researchers to use different implementation formalisms. Many efforts were dedicated to develop cellular space models in DEVS in order to employ the advantage of discrete event systems. Unfortunately, the conventional implementations degrade the performance in large scale cellular models because of the huge volume of inter-cell messages generated during simulation. This work introduces a new multi-layer formalism for cellular DEVS models that assures high performance and ease of user specification. It starts with the parallel DEVS specification layer and derives a high performance cellular DEVS layer using the property of closure under coupling. This is done through converting the parallel DEVS into its equivalent non-modular form which involves computational and communication overhead tradeoffs. The new specification layer, in contrast to multi-component DEVS, is identical to the modular parallel DEVS in the sense of state trajectories which are updated according to the modular message passing methodology. The equivalency of the two forms is verified using simulation methods. Once the equivalency has been ensured, analysis of the models becomes a decisive factor in employing modularity in cellular DEVS models. Non-modular models show significant speedup in simulation runs given that their event list handler is implemented based on analytical and experimental survey that involve actual operation counts. However, the new high performance non-modular specification layer is complicated to implement. Therefore, a third layer of specification is proposed to provide a simple user specification that is automatically converted into the fast complex cellular DEVS specification, which is finally put in the standard parallel DEVS specification. A tool was implemented to automatically accept user's model specification via GUI and generate the models using the new specifications. The generated models are then required to be tested and verified using some automatic DEVS verification methods. As a result, the model development and verification processes are made easier and faster.

Service Oriented Architectures (SOA) present challenges to current model-based software engineering methodologies such as Rational Unified Process (RUP). In this research effort we propose a process called DEVS Unified Process (DUNIP) that uses the DEVS formalism as a basis for automated generation of models from various requirement specifications and realization as SOA collaborative services. DEVS is inherently based on object oriented methodology and systems theory, and categorically separates the Model, the Simulator and the Experimental frame, and has been used for systems Modeling & Simulation over the years. DUNIP integrates these concepts into DEVSbased Bifurcated Model-Continuity life-cycle development methodology. The life-cycle begins by specifying the system requirements in a number of different formats such as state-based, BPMN/BPEL-based, message-based requirement specifications. DUNIP then automates the generation of DEVS models capable for distributed collaboration. The collaboration uses an XML-based DEVS Modeling Language (DEVSML) framework that provides the capability to integrate models that may be expressed in different DEVS implementation languages. The models are also made available for remote and distributed real-time execution over the SOA middleware in a manner transparent to the user. A prototype simulation framework has been implemented and is illustrated with an application to a system of collaborating military systems implemented and tested using Bifurcated Model-Continuity methodology. We also show how the Department of Defense Architecture Framework (DoDAF) can be enhanced to incorporate simulation based executable models using the DUNIP process.

Interoperability between heterogeneous software systems is an important issue to increase software reusability in the software industry. Many methods are proposed to implement interoperable systems using distributed computing infrastructures such as CORBA, HLA and SOA. Those infrastructures can provide communication channels between software systems with heterogeneous environments. SOA (Service Oriented Architecture) provides a more flexible approach to interoperability than do the others because it provides platform independence and employs platform-neutral message passing with Simple Object Access Protocol (SOAP) to communicate between a service and a client.The main contribution of this study is to design and implement an interoperable DEVS simulation environment using the SOA concept and a new construct called the DEVS namespace. The interoperable DEVS environment consists of a DEVS simulator service and an associated integrator. The DEVS simulator service provides both simulator level and model level interoperability. Moreover, using the DEVS namespace, DEVS simulator services can be interoperable with any services using the same message types.To demonstrate the utility of the proposed environment, we describe various applications of the interoperable DEVS simulation environment. The applications are drawn from real world development of automated testing environments for military information system interoperability. A radar track generation and display federation and a model negotiation web service illustrated the ability of the proposed middleware to work across platforms and languages. Its ability to support higher level semantic interoperability will be demonstrated in a testing service that can deploy model agents to provide coordinated observation of web requests of participants in simulated distributed scenarios.

This paper contains brief introduction into modeling and simulation using Discrete Event Specified System (DEVS) formalism. It defines basic models (atomic and coupled DEVS) and shows how they are simulated. Examples of derived DEVS formalism like parallel DEVS or DESS are also presented. It is described how to create DEVS models using graphic modeling software and advantages and disadvantages of this approach. A short summary of known programs are also covered. Storing models in the XML language, validation of XML document and transformation capabilities by XSLT are discussed. The main section is dedicated to the design of a graphic editor for simulation models inspired by design patterns including classes for canvas, model representation, export module interface and main application. The XML document used for storing DEVS models and simple DEVS simulator are also described. Implementation section presents used programming libraries, reasons why they have been used and their advantages and disadvantages. Paper ends with an example of a simple DEVS model created by implemented graphic editor for simulation DEVS models.

With the advance in applying technology in education, the traditional lecture-driven teaching style is gradually replaced by a more active teaching style where the students play a more active rule in the learning process. In this paper we introduce a new initiative to provide a suite of online tools for learning DEVS model. The uniqueness of this tutorial project is the integration of information technology and multimedia into education through the development of an interactive tutorial and the characteristic of contextualized learning. The tutorial teaches students about the basic aspects of discrete event system and simulation. The interactive tutorial fully utilizes the power of the information and multimedia technology, web application and the programming language Java, to enhance students’ learning to achieve rich interactivity. The tutorial greatly supports human-computer collaboration to enhance learning and to satisfy user goals by effectively allowing the user to interact.

As network uses increase rapidly and high quality-of-service (QoS) is required, efficient network managing methods become important. Many previous studies and commercial tools of network management systems such as tcpdump, Ethereal, and other applications have weaknesses: limited size of files, command line execution, and large memory and huge computational power requirement. Researchers struggle to find fast and effective analyzing methods to save maintenance budgets and recover from systematic problems caused by the rapid increment of network traffic or intrusions. The main objective of this study is to propose an approach to deal with a large amount of network behaviors being quickly and efficiently analyzed. We study an ontology/data engineering methodology based network analysis system. We design a behavior, which represents network traffic activity and network packet information such as IP addresses, protocols, and packet length, based on the System Entity Structure (SES) methodology. A significant characteristic of SES, a hierarchical tree structure, enables systems to access network packet information quickly and efficiently. Also, presenting an automated system design is the secondary purpose of this study. Our approach shows adaptive awareness of pragmatic frames (contexts) and makes a network traffic analysis system with high throughput and a fast response time that is ready to respond to user applications. We build models and run simulations to evaluate specific purposes, i.e., analyzing network protocols use, evaluating network throughput, and examining intrusion detection algorithms, based on Discrete Event System Specification (DEVS) formalism. To study speed up, we apply a web-based distributed simulation methodology. DEVS/Service Oriented Architecture (DEVS/SOA) facilitates deploying workloads into multi-servers and consequently increasing overall system performance. In addition to the scalability limitations, both tcpdump and Ethereal have a security issue. As well as basic network traffic information, captured files by these tools contain secure information: user identification numbers and passwords. Therefore, captured files should not allow to be leaked out. However, network analyses need to be performed outside target networks in some cases. The distributed simulation--allocating distributing models inside networks and assigning analyzing models outside networks--also allows analysis of network behaviors out of networks while keeping important information secured.

This master's thesis deals with the issue of modeling and simulation of systems based on the DEVS formalism. The result of this work is a library that is inspired by the adevs tool and based on the classical DEVS formalism. The library is implemented in the programming language C++20 and is supplemented by predefined models of components for creation of queueing systems. The library also contains a set of examples for use in teaching. In comparison with the paralel adevs tool it is less effective but it has simpler interface with focus on clarity, which is more important for teaching. The library also simplifies definition of models with the use of modules, intelligent pointers for memory management and the use of mentioned components.