A utilização da Internet como um meio de automação de serviços de e-business tem sido adotada como estratégia por empresas em vários ramos da economia, diminuindo custos e propiciando uma melhoria no relacionamento com o cliente. Um requisito não-funcional importante a ser considerado no desenvolvimento de sistemas de software que possibilita esta automação é a disponibilidade. O nível de disponibilidade de um sistema pode ser influenciado pela arquitetura do sistema, e, em particular, pela arquitetura de software, pois as decisões arquitetônicas devem considerar aspectos relacionados à disponibilidade. No método de avaliação de arquitetura ATAM (Architecture Tradeoff Analysis Method Método de Análise de Compromissos de Arquitetura), esse requisito é analisado através da utilização de cenários de disponibilidade. Como a avaliação da disponibilidade é normalmente uma tarefa complexa, requerendo dos analistas a identificação de numerosos itens interdependentes, a geração e, conseqüentemente, a análise de cenários de disponibilidade na maioria das vezes não é uma tarefa trivial. O presente trabalho tem como objetivo elaborar uma técnica de análise de disponibilidade em sistemas de software para a Web, que auxilie a geração sistemática de cenários de disponibilidade requeridos no método ATAM. Para a elaboração da proposta, o trabalho aborda métodos para a elicitação, representação e análise de requisitos não-funcionais em uma determinada arquitetura de software, bem como conceitos e taxonomias relacionadas à dependabilidade. Ao final, a técnica é exercitada em um exemplo simplificado de sistema de software bancário na Web. / The use of Internet for e-business service automation has been adopted as a strategy by organizations in several sectors of the economy, reducing costs and providing a better relationship with the customer. Availability is an important nonfunctional requirement to be considered in the development of software systems offering this type of automation. The level of system availability may be affected by the system architecture, and, especially, by the software architecture, as architectural decisions must take availability-related aspects into account. In the ATAM (Architecture Tradeoff Analysis Method) architecture evaluation method, this requirement is analyzed by means of availability scenarios. As availability evaluation is normally a complex task, requiring analysts to identify several interdependent items, the generation and, consequently, the analysis of availability scenarios is often not a trivial task. This work aims to elaborate an availability technique analysis for web-based software systems, to aid in the systematic generation of availability scenarios required in the ATAM method. To elaborate the proposal, the work covers methods for elicitation, representation and analysis of non-functional requirements in a specific software architecture, as well as concepts and taxonomies related to dependability. In the end, the technique is applied on a simplified example of web banking software system.

Les véhicules automobiles autonomes sont des systèmes critiques. En effet, suite à leurs défaillances, ils peuvent provoquer des dégâts catastrophiques sur l'humain et sur l'environnement dans lequel ils opèrent. Le contrôle des véhicules autonomes robotisés est une fonction complexe, qui comporte de très nombreux modes de défaillances potentiels. Dans le cas de plateformes expérimentales qui n'ont suivi ni les méthodes de développement ni le cycle de certification requis pour les systèmes industriels, les probabilités de défaillances sont beaucoup plus importantes. En effet, ces véhicules expérimentaux se heurtent à deux problèmes qui entravent leur sûreté de fonctionnement, c'est-à-dire la confiance justifiée que l'on peut avoir dans leur comportement correct. Tout d'abord, ils sont utilisés dans des environnements ouverts, au contexte d'exécution très large. Ceci rend leur validation très complexe, puisque de nombreuses heures de test seraient nécessaires, sans garantie que toutes les fautes du système soient détectées puis corrigées. De plus, leur comportement est souvent très difficile à prédire ou à modéliser. Cela peut être dû à l'utilisation des logiciels d'intelligence artificielle pour résoudre des problèmes complexes comme la navigation ou la perception, mais aussi à la multiplicité de systèmes ou composants interagissant et compliquant le comportement du système final, par exemple en générant des comportements émergents. Une technique permettant d'augmenter la sécurité-innocuité (safety) de ces systèmes autonomes est la mise en place d'un composant indépendant de sécurité, appelé « Safety-Bag ». Ce système est intégré entre l'application de contrôle-commande et les actionneurs du véhicule, ce qui lui permet de vérifier en ligne un ensemble de nécessités de sécurité, qui sont des propriétés nécessaires pour assurer la sécurité-innocuité du système. Chaque nécessité de sécurité est composée d'une condition de déclenchement et d'une intervention de sécurité appliquée quand la condition de déclenchement est violée. Cette intervention consiste soit en une inhibition de sécurité qui empêche le système d'évoluer vers un état à risques, soit en une action de sécurité afin de remettre le véhicule autonome dans un état sûr. La définition des nécessités de sécurité doit suivre une méthode rigoureuse pour être systématique. Pour ce faire, nous avons réalisé dans nos travaux une étude de sûreté de fonctionnement basée sur deux méthodes de prévision des fautes : AMDEC (Analyse des Modes de Défaillances, leurs Effets et leur Criticité) et HazOp-UML (Etude de dangers et d'opérabilité) qui mettent l'accent respectivement sur les composants internes matériels et logiciels du système et sur l'environnement routier et le processus de conduite. Le résultat de ces analyses de risques est un ensemble d'exigences de sécurité. Une partie de ces exigences de sécurité peut être traduite en nécessités de sécurité implémentables et vérifiables par le Safety-Bag. D'autres ne le peuvent pas pour que le système Safety-Bag reste un composant relativement simple et validable. Ensuite, nous avons effectué des expérimentations basées sur l'injection de fautes afin de valider certaines nécessités de sécurité et évaluer le comportement de notre Safety-Bag. Ces expériences ont été faites sur notre véhicule robotisé de type Fluence dans notre laboratoire dans deux cadres différents, sur la piste réelle SEVILLE dans un premier temps et ensuite sur la piste virtuelle simulée par le logiciel Scanner Studio sur le banc VILAD. Le Safety-Bag reste une solution prometteuse mais partielle pour des véhicules autonomes industriels. Par contre, il répond à l'essentiel des besoins pour assurer la sécurité-innocuité des véhicules autonomes expérimentaux. / Autonomous automotive vehicles are critical systems. Indeed, following their failures, they can cause catastrophic damage to the human and the environment in which they operate. The control of autonomous vehicles is a complex function, with many potential failure modes. In the case of experimental platforms that have not followed either the development methods or the certification cycle required for industrial systems, the probabilities of failure are much greater. Indeed, these experimental vehicles face two problems that impede their dependability, which is the justified confidence that can be had in their correct behavior. First, they are used in open environment, with a very wide execution context. This makes their validation very complex, since many hours of testing would be necessary, with no guarantee that all faults in the system are detected and corrected. In addition, their behavior is often very difficult to predict or model. This may be due to the use of artificial intelligence software to solve complex problems such as navigation or perception, but also to the multiplicity of systems or components interacting and complicating the behavior of the final system, for example by generating behaviors emerging. A technique to increase the safety of these autonomous systems is the establishment of an Independent Safety Component, called "Safety-Bag". This system is integrated between the control application and the actuators of the vehicle, which allows it to check online a set of safety necessities, which are necessary properties to ensure the safety of the system. Each safety necessity is composed of a safety trigger condition and a safety intervention applied when the safety trigger condition is violated. This intervention consists of either a safety inhibition that prevents the system from moving to a risk state, or a safety action to return the autonomous vehicle to a safe state. The definition of safety necessities must follow a rigorous method to be systematic. To do this, we carried out in our work a study of dependability based on two fault prevention methods: FMEA and HazOp-UML, that respectively focus on the internal hardware and software components of the system and on the road environment and driving process. The result of these risk analyzes is a set of safety requirements. Some of these safety requirements can be translated into safety necessities, implementable and verifiable by the Safety-Bag. Others cannot be implemented in the Safety-Bag. The latter must remain simple so that it is easy to be validated. Then, we carried out experiments based on the faults injection in order to validate some safety necessities and to evaluate the Safety-Bag's behavior. These experiments were done on our robotic vehicle type Fluence in our laboratory in two different settings, on the actual track SEVILLE at first and then on the virtual track simulated by the Scanner Studio software on the VILAD testbed. The Safety-Bag remains a promising but partial solution for autonomous industrial vehicles. On the other hand, it meets the essential needs for the safety of experimental autonomous vehicles.

Made available in DSpace on 2016-04-27T16:58:11Z (GMT). No. of bitstreams: 1 dissertacao_edelweiss_pelho.pdf: 627142 bytes, checksum: 04030b3bcd8d33310f91dc5abfe76e75 (MD5) Previous issue date: 2003-05-05 / This research aims to introduce the concept of function throughout the comprehension of the dependable and undependable variables, and of the relation between them. Its fundaments are on the Didactics Engineering principles by the creation and application of a teaching activity sequence and a posterior analysis of the collected data. It is based on Raymond Duval s Theory of Semiotic Representation of Register. The teaching activity sequence is derived from the research of Kieran & Sfard (1999) about the algebra school mathematics teaching and a Duval s research (1988) about the articulation between the graphical and algebraic registers. On of the teaching tools used during the application of the activity sequence was a software called Cabri-Géomètre II, besides paper and pencils. The activity sequence was applied to second-year-high school students in a private school in the city of Araçatuba, northwest of the state of São Paulo, Brazil. The protocols of six pairs of the participating students presents in every section were analyzed. The results convey the existence of a certain increase among the students of the development in understanding the concept due to the comprehension and the relation between the variables as well as to the corresponding articulation among the different representation registers of the function / O objetivo deste trabalho é introduzir o conceito de função por meio da compreensão das variáveis dependentes e independentes, e do relacionamento entre elas. Fundamenta-se nos princípios da Engenharia Didática com a elaboração e aplicação de uma seqüência de ensino e posterior análise dos dados coletados. Está embasado na Teoria dos Registros de Representação Semiótica de Raymond Duval. A seqüência de ensino orienta-se em uma pesquisa de Kieran e Sfard (1999), sobre o ensino da álgebra escolar e em um trabalho Duval (1988) sobre a articulação entre os registros gráfico e algébrico. Uma das ferramentas de ensino utilizadas na aplicação da seqüência foi o software Cabri-Géomètre II, além do uso de apenas papel e lápis. A seqüência foi aplicada com alunos do segundo ano do ensino médio de uma escola particular da cidade de Araçatuba, interior do estado de São Paulo. Foram analisados os protocolos de seis duplas, que participaram de todas as sessões. Os resultados obtidos levam a concluir que houve uma evolução por parte dos alunos, na apreensão do conceito de função, propiciado pela compreensão e relacionamento entre as variáveis e pelas devidas articulações entre os diferentes registros de representação da função

A utilização da Internet como um meio de automação de serviços de e-business tem sido adotada como estratégia por empresas em vários ramos da economia, diminuindo custos e propiciando uma melhoria no relacionamento com o cliente. Um requisito não-funcional importante a ser considerado no desenvolvimento de sistemas de software que possibilita esta automação é a disponibilidade. O nível de disponibilidade de um sistema pode ser influenciado pela arquitetura do sistema, e, em particular, pela arquitetura de software, pois as decisões arquitetônicas devem considerar aspectos relacionados à disponibilidade. No método de avaliação de arquitetura ATAM (Architecture Tradeoff Analysis Method Método de Análise de Compromissos de Arquitetura), esse requisito é analisado através da utilização de cenários de disponibilidade. Como a avaliação da disponibilidade é normalmente uma tarefa complexa, requerendo dos analistas a identificação de numerosos itens interdependentes, a geração e, conseqüentemente, a análise de cenários de disponibilidade na maioria das vezes não é uma tarefa trivial. O presente trabalho tem como objetivo elaborar uma técnica de análise de disponibilidade em sistemas de software para a Web, que auxilie a geração sistemática de cenários de disponibilidade requeridos no método ATAM. Para a elaboração da proposta, o trabalho aborda métodos para a elicitação, representação e análise de requisitos não-funcionais em uma determinada arquitetura de software, bem como conceitos e taxonomias relacionadas à dependabilidade. Ao final, a técnica é exercitada em um exemplo simplificado de sistema de software bancário na Web. / The use of Internet for e-business service automation has been adopted as a strategy by organizations in several sectors of the economy, reducing costs and providing a better relationship with the customer. Availability is an important nonfunctional requirement to be considered in the development of software systems offering this type of automation. The level of system availability may be affected by the system architecture, and, especially, by the software architecture, as architectural decisions must take availability-related aspects into account. In the ATAM (Architecture Tradeoff Analysis Method) architecture evaluation method, this requirement is analyzed by means of availability scenarios. As availability evaluation is normally a complex task, requiring analysts to identify several interdependent items, the generation and, consequently, the analysis of availability scenarios is often not a trivial task. This work aims to elaborate an availability technique analysis for web-based software systems, to aid in the systematic generation of availability scenarios required in the ATAM method. To elaborate the proposal, the work covers methods for elicitation, representation and analysis of non-functional requirements in a specific software architecture, as well as concepts and taxonomies related to dependability. In the end, the technique is applied on a simplified example of web banking software system.

Com o aumento do uso de sistemas elétricos, eletrônicos e programáveis em aplicações de diversos domínios, tais como entretenimento, realização de transações financeiras, distribuição de energia elétrica, controle de processos industriais e sinalização e controle em transporte de passageiros e carga, é essencial que as políticas de manutenção utilizadas sejam capazes de minimizar os custos associados a eventuais falhas que afetem negativamente os serviços providos. Ao longo das últimas décadas, foi sedimentada a tendência de que a adoção de técnicas de manutenção preditiva representa uma das abordagens mais viáveis e promissoras para que falhas de sistemas utilizados em diversas aplicações possam ser detectadas antes de elas efetivamente ocorrerem. Considerando-se que uma parcela significativa dos estudos recentes na área de manutenção preditiva de sistemas apresenta como limitação o custo elevado para se instalar uma infraestrutura específica para realizar a coleta de dados que serão usados para dar suporte à predição das falhas futuras de um sistema, o modelo proposto no presente estudo visa permitir que os índices de dependabilidade e as falhas futuras de sistemas elétricos, eletrônicos e programáveis sejam estimados utilizando-se dados já disponíveis de falhas e manutenções passadas. Para tanto, foram empregadas técnicas como processos estocásticos, filtragem Kalman e modelos de incorporação de dados de histórico preconizados no padrão internacional RIAC-HDBK-217Plus. Como principal conclusão do presente trabalho, é possível ressaltar que foi possível atingir, com o modelo proposto, o objetivo de suporte à manutenção preditiva de sistemas elétricos, eletrônicos e programáveis a partir do uso de dados preexistentes de histórico operacional; no entanto, foram constatadas limitações no grau de utilização prática do modelo em situações nas quais a quantidade dos dados de histórico disponíveis para consulta é pequena. / With the increased use of electrical, electronic and programmable systems in various application fields such as entertainment, financial transactions, power distribution, industrial process control and signaling and control of transportation modes, it is essential for the maintenance policies used in those systems to be able to minimize the costs of any faults that may adversely affect the services provided. Over the past decades, the use of predictive maintenance techniques has shown to be a viable and promising approach to detect faults before they actually occur in systems used in different application fields. Considering that a significant part of the recent scientific research in the area of predictive maintenance usually demands high-cost infrastructure to be installed to support the acquisition of all the data that will be used to calculate the prediction of future faults of a system, the model proposed within this study was designed to allow both dependability levels and future faults of electrical, electronic and programmable systems to be estimated using past faults and maintenance data that may already be available. For this purpose, techniques such as stochastic processes, Kalman filtering and models prescribed within the international standard RIAC-HDBK-217Plus to incorporate history data to dependability calculation were used. As the main conclusion of this study, it is possible to highlight that the main objective of the model proposed, related to its ability to support predictive maintenance of electrical, electronic and programmable systems through the use of pre-existing operating history data, has been reached; nevertheless, limitation of practical use of the model was verified in situations in which not enough operating data is available.

Non-functional requirements such as Security and Dependability (S&D) become more and more important as well as more and more difficult to achieve, particularly in embedded systems development. Such systems come with a large number of common characteristics, including real-time and temperature constraints, security and dependability as well as efficiency requirements. In particular, the development of Resource Constrained Embedded Systems (RCES) has to address constraints regarding memory, computational processing power and/or energy consumption. In this work, we propose a modeling environment which associates model-driven paradigm and a model-based repository, to support the design and the packaging of S&D patterns, resource models and their property models. The approach is based on a set of modeling languages coupled with a model-repository, search and instantiation engines towards specific development environments. These modeling languages allow to specify patterns, resources and a set of property models. These property models will allow to govern the use of patterns and their analysis for reuse. In addition, we propose a specification and generation process of repositories. As part of the assistance for the development of S&D applications, we have implemented a suite of tool-chain based on the Eclipse platform to support the different activities around the repository, including the analysis activities. The proposed solutions were evaluated in the TERESA project through a case study from the railway domain.

Le but de ce rapport est de présenter une méthode globale de développement à partir de spécifications informelles, depuis la modélisation graphique des exigences temporelles d'un système ferroviaire critique jusqu'à une implantation systématique au moyen de méthodes formelles. Nous proposons d'utiliser ici les réseaux de Petri temporels pour décrire le comportement attendu du logiciel de contrôle-commande à construire.Tout d'abord nous construisons un modèle des exigences p-temporel prenant en compte toutes les contraintes que doit vérifier le système. Nous proposons des outils et des méthodes capables de valider et de vérifier ce modèle. Ensuite, il s'agit de construire un modèle de processus solution en réseau de Petri t-temporel. Ce modèle illustre des exigences techniques relatives à un choix technologique ou architectural. L'objectif est double : tout d'abord il est nécessaire de vérifier la traçabilité des exigences ; ensuite, il faut vérifier que l'ensemble des exigences sources sont bien implémentées dans la solution préconisée et dans sa mise en oeuvre. Enfin, nous proposons une approche visant à transformer de façon systématique le modèle de processus en machine abstraite $B$ afin de poursuivre une procédure formelle $B$ classique. Finalement, le cas d'étude du passage à niveau, composant critique dans le domaine de la sécurité ferroviaire est décrit / The introduction of new European standards for railway safety, coupled with an increasing use of software technology changes the method of development of critical railway systems. Indeed, new systems have to be at least as good as the previous ones. Therefore the appropriate safety level of critical systems has to be proved in order to obtain the necessary approval from the authorities. Accordingly a high level of reliability and correctness must be reached by the use of mathematical proofs and then formal methods. We focus on the treatment of the temporal requirements in the level crossing case study which is modelled with p-time Petri nets, and on the translation of this model in a more formal way by using the B method. This paper introduces a methodology to analyse the safety of timed discrete event systems. First, our goal is to take out the forbidden state highlighted by a p-time Petri net modelling. This model deals with the requirements of the considered system and has to contain all the constraints that have to be respected. Then we aim at describing a process identified as a solution of the system functioning. This method consists in exploring all the possible behaviours of the system by means of the construction of state classes. Finally, we check if the proposed process corresponds to the requirements model previously built.Our case-study is the level crossing, a critical component for the safety of railway systems

Depuis son invention, l'électricité joue un rôle essentiel dans notre vie quotidienne. L'apparition des premières installations de production d'électricité à la fin du XIXème siècle a ouvert la voie au système électrique et à ses sous-systèmes. Les consommateurs d'énergie électrique exigent un service fiable en termes de stabilité et de sécurité du réseau électrique. Depuis la libéralisation des marchés, les producteurs d'énergie électrique, les fournisseurs de services publics et d'équipements, en tant qu'acteurs principaux, suivent une tendance émergente pour satisfaire les demandes des consommateurs. Cette tendance implique l'amélioration des technologies, l'innovation et le respect des normes et des réglementations gouvernementales. Tous ces efforts ont été qualifiés de concept de réseaux intelligents (Smart Grid en anglais) qui évolue pour répondre aux demandes futures.Les sous-stations numériques modernes et futures façonnent des nœuds essentiels dans le réseau électrique, où la stabilité du flux d'énergie électrique, la conversion des niveaux de tension et la protection de l'équipement du poste de commutation figurent parmi les principaux rôles de ces nœuds. La norme prometteuse CEI 61850 et ses composants apportent de nouvelles fonctionnalités aux systèmes d'automatisation des postes. L'utilisation de la communication Ethernet dans ces systèmes réduit la quantité de connexions câblées qui réduit l'encombrement de l'équipement de la sous-station, des dispositifs et de leur câblage.L'intégration des nouvelles fonctionnalités CEI 61850 au niveau des sous-stations requiert des compétences multidisciplinaires. Par exemple, considérons les tâches de protection et de contrôle de la puissance d'un côté et les technologies de l'information et de la communication de l'autre. La dépendance entre les fonctions d'automatisation des sous-stations et les réseaux de communication à l'intérieur d'une sous-station pose de nouveaux défis aux concepteurs, intégrateurs et testeurs. Ainsi, étudier la fiabilité des fonctionnalités du système, par exemple, les schémas de protection, exige de nouvelles méthodes d'essai où les méthodes conventionnelles ne sont pas applicables. Les nouvelles techniques devraient fournir des moyens d'évaluer les performances des systèmes conçus et de vérifier leur conformité aux exigences des normes.Afin d'améliorer la fiabilité du système conçu, ce travail vise à développer des méthodes pour tester les systèmes d'automatisation de sous-station CEI 61850, en particulier sur les processus et les niveaux de la baie, dans une plate-forme dédiée aux tâches de recherche. Cette plate-forme incorpore des dispositifs de pointe et des cartes de test qui aideront à observer simultanément les interactions dynamiques des transitoires de puissance et les perturbations du réseau de communication. Les données obtenues lors des tests expérimentaux seront utilisées pour diagnostiquer les défaillances et classer leurs causes afin de les supprimer et d'améliorer la fiabilité du système conçu. / Since its invention, Electricity has played a vital role in our everyday life. The appearance of the first power production facilities in the late nineteenth century paved the way for the electrical power system and its subsystems. Consumers of electric power demand dependable service in terms of power grid stability and safety. Since the liberalization of the markets, producers of electric power, utilities and equipment suppliers, as principal players, are following an emerging trend to satisfy consumers’ demands. This trend involves improving technologies, innovating and respecting standards requirements and governments’ regulations. All these efforts termed as the concept of the Smart Grid that is evolving to meet future demands.Modern and future digital substations shape essential nodes in the grid, where stability of electric power flow, converting of voltage levels and protecting switchyard equipment are among the primary roles of these nodes. The promising standard IEC 61850 and its parts, bring new features to the substation automation systems. The use of Ethernet based communication within these systems reduces the amount of hardwired connections that results in lowering footprint of substation equipment, devices and their cabling.Integration of the new IEC 61850 features at the substation levels requires multidiscipline competences. For instance, consider power protection and control tasks from one side and information and communication technologies from the other side. Dependency between substation automation functions and communication networks inside a substation brings new kinds of challenges to designers, integrators and testers. Thus, investigating the dependability of the system functionalities, e.g. the protection schemes, requires new methods of testing where conventional methods are not applicable. The new techniques should provide means to evaluate performance of designed systems and checking their conformance to the standards requirements.In order to improve the designed system dependability, this work aims to develop methods for testing the IEC 61850 enabled substation automation systems, especially on the process and the bay levels, in a platform dedicated for research tasks. This platform incorporates state-of-art devices and test-set cards that will help to simultaneously observe dynamic interactions of the power transients and communication network perturbations. Data obtained during the experimental tests will be used for diagnosing of failures and classifying their causes in order to remove them and enhance dependability of the designed system.

Les systèmes RFID – pour RadioFrequency Identification – sont capables d’identifier des objets ou des personnes sans contact ni vision direct. Ainsi, leur utilisation grandit de manière exponentielle dans différents secteurs : nucléaire, aviation, ferroviaire, médical, traçabilité, contrôle d’accès… Mais ce sont surtout des systèmes fortement hétérogènes, composés de matériel analogique ou digital, et de systèmes informatique : le tag, attaché à l’objet à identifier, contenant l’identifiant de ce dernier ; le lecteur, appareil capable de venir lire les informations contenus dans les tags ; et le système informatique gérant l’ensemble des données générées par le système. Ces systèmes sont de plus en plus utilisés dans des domaines critiques ou dans des environnements difficiles, alors qu’ils sont basés uniquement sur des équipements bas coût et peu performant – les tags – ne permettant alors pas de garantir des communications robustes. Tous ces points font que le test en ligne des systèmes RFID est une tâche complexe.Cette thèse s’intéresse donc à la sûreté de fonctionnement des systèmes RFID : comment être certains que le système fonctionne comme il faut au moment où on en à besoin ? En premier, les défaillances et leurs causes ont été étudiées à l’aide d’une méthode classique : AMDE – Analyse des modes de défaillances et de leurs effets. Cette étude a permis d’identifier les points faibles des systèmes RFID. Après cela et grâce à cette analyse, il nous a été possible de définir et d’implémenter un simulateur de systèmes RFID appelé SERFID, pour Simulation et Evaluation des systèmes RFID. Ce simulateur est capable de simuler différents systèmes RFID multi-équipements (HF ou UHF, normes actuellement implémentées : ISO15693 et EPC Classe 1 Génération 2), du tag au lecteur, en passant par le canal de communication permettant aux tags et aux lecteurs de communiquer. SERFID permet aussi de connecter les lecteurs simulés à des middlewares existants ou nouveau afin des les évaluer. Pour permettre l’évaluation de la sûreté de fonctionnement des systèmes RFID, SERFID permet l’injection de fautes dynamiquement au sein des tags, lecteurs ou du canal de communication permettant de simuler différentes défaillances pouvant apparaître : diminution de la qualité de la communication ou de l’alimentation du tag, erreurs au sein de la mémoire du tag, bruit… SERFID a été notamment utilisé pour simuler et observer le comportement de systèmes RFID HF et UHF face à du bruit et des perturbations dans le canal de communication entre le tag et le lecteur. Finalement, cette thèse propose une nouvelle méthode pour détecter les tags fautifs ou vieillissants dans les applications de logistiques. Cette méthode, non intrusive et en ligne, est basée sur l’observation des performances du système au cours de son fonctionnement : le logiciel de gestion analyse les résultats des différentes identifications. A partir du taux d’erreur de lecture par tag, et en le comparant aux taux de lecture par tag précédemment observés, cette méthode est capable de déterminer quel groupe de tags est fautif ou non. Cette méthode a été évaluée par expérimentation et par simulation grâce à SERFID. Cette évaluation a permis de mettre en évidence les points forts et les faiblesses de la méthode. / RFID systems – for RadioFrequency Identification – are able to identify object or person without any contact or direct vision. For this reason, their use grows exponentially in many different fields: nuclear, avionics, railways, medical, warehouse inventories, access control… However they are complex heterogeneous systems, consisting of analog and digital hardware components and software components: the tag, closed on the object to identified, which contains its identifier; the reader which able to read identifiers on tags; and finally the IT infrastructure to manage data. RFID technologies are often used into critical domains or within harsh environments. But as RFID systems are only based on low cost and low-performance equipments, they do not always ensure robust communications. All these points make the on-line testing of RFID systems a very complex task.This thesis focuses on dependability of RFID systems: how to be sure that this system works correctly when we need to use it? Firstly, failures and their causes have been studied using a common method called FMEA – Failure Modes and Effects Analysis – This study allows to identify weakness aspects of RFID systems. After that and thanks to this analysis, a new simulator was designed and implemented. This simulator, called SERFID for Simulation and Evaluation of RFID systems, is able to simulate various RFID systems with many devices (HF or UHF, actually implemented standards: ISO15693 or EPC Class 1 Generation 2), from tag to reader, together with the RF channel between them and the physic aspect which permit to tags and readers to communicate. SERFID also permits to connect an existing or new middleware to simulated reader to evaluate new software approach. To analyze dependability of RFID systems, SERFID allows us to inject fault in tag, channel or readers dynamically, to simulate different failures which can be appear: decrease of quality of communication or tag supply, memory errors in tag, noises… SERFID was in particular use to simulate HF and UHF RFID systems to observe their reaction according noises and disturbances in communication between tag and reader. Finally, a new method to detect faulty or aging tags or readers in traceability application was proposed. This non-intrusive on-line method is based on performance observation of the system during operation: the managing software analyzes results of an identification round. According read error rate per tag of an inventory, and comparing it with previous obtained read error rates per tag, this method is able to determine which group of tags is faulty or not. This method has been analyzed with to method: by experimentations and by simulation using SERFID. This analyze brings out weakness and strength of this method.

Un système de distribution électrique est le cœur de tous types de sites industriels, aussi bien les sites producteurs d'énergie que les sites consommateurs. La sécurité de ce système doit être impérativement assurée par la mise en place des unités assurant plusieurs fonctionnalités de protection contre les dédauts électriques. Parmi ces fonctionalités il existe celles qui se basent sur des échanges d'information entre plusieurs unités de protection. Le standard IEC 61850 guarantit cet échange des informations via des signaux ‘temps réel' échangé via le réseau de communication. Vue l'aspet non deterministe de ces signaux, une étude poussée de leur fiabilité doit être effectuée. Pour ces raisons notre travail de thèse a pour objectif de mettre en place une méthodologie, basée sur une plateforme de Co-Simulation conçue pendant notre étude, qui permet la validation de la fiabilité de ces messages tout au long du cycle de vie d'un système de communication IEC 61850. / From 2004, a new worldwide standard of communication IEC61850 is introduced in the majority of substation automation system carrying out new innovation prospects to the world of substation. One of these feature is that it allows the exchange of security real time communication messages all over the communication network. These messages are used as control information for the Distributed Automation Application 'DAA'. Taking into consideration that DAA have a direct effect on ythe dependability of a smart grid architecture, the fiability of these real time IEC 61850 should be evaluated. For these reasons, our research delas with the development of a Co-Simulation platform that permits the evaluation and validation of an IEC 61850 communication network.