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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
131

A prática de seleção de frameworks web cliente de código aberto : fundamentos para a construção de uma base de conhecimento

Makiyama, Daniel Souza, Braga, Juliana C. (Braga, Juliana Cristina) January 2015 (has links)
Orientadora: Profa. Dra. Gordana Manic / Dissertação (mestrado) - Universidade Federal do ABC, Programa de Pós-Graduação em Ciência da Computação, 2015. / A tecnologia dos navegadores de internet evolui rapidamente. Hoje, o padrão HTML51 provê uma gama enorme de recursos gráficos e de interação. Com um navegador mais poderoso e uma clientela mais exigente, demanda-se mais complexidade da camada do cliente. Esta complexidade demanda maior preocupação com a arquitetura de soluções nesta camada. Há uma infinidade de frameworks2 atualmente, para organizar e potencializar a camada cliente da web3, e consequente dificuldade em lidar com este volume de informações. A escolha de frameworks por parte do desenvolvedor pode ser pragmática, a negação da escolha ou a criação de uma nova opção específica para o seu problema. A falta de um corpo de conhecimento acessível dificulta o processo de aprendizagem e engajamento dos profissionais no reuso das melhores práticas disponíveis em seus projetos. A partir da análise de arquiteturas web na plataforma do cliente, revisão sistemática do estado da arte nos métodos empíricos de seleção de componentes de software, esta dissertação apresenta os resultados de uma pesquisa realizada com 26 profissionais de tecnologia e 3 especialistas de usabilidade, que utilizaram um protótipo construído para esta pesquisa, para a experimentação e composição de soluções a partir de fragmentos de código empregando diferentes frameworks. O experimento objetivou mapear as necessidades de umsistema que se aproxime à prática de seleção de frameworks, e mapear como um grupo de profissionais envolvidos com computação utilizariam este tipo de ferramenta. Segundo o estudo, demonstrações de código são a fonte de informação que mais auxilia na adoção de um framework e fragmentos de código exercem comprovada influência no resultado final de implementação deste tipo de aplicação. Os diferenciais da base de conhecimento proposta é capacidade de integrar códigos, avaliações e análise de desempenho objetivando criar padrões de código para aprendizado ou uso imediato. O uso de um protótipo funcional e o envolvimento precoce dos usuários em testes de usabilidade foi muito positivo à elicitação de uma lista completa de requisitos funcionais e não funcionais para esta ferramenta. / The browser¿s technologies rapidly evolve. Today, the HTML5 standard provides a huge range of graphic and interaction resources. With a more powerful browser and customers that demands more, more complexity in the client tier is required. This complexity demands greater concern with architecture solutions in this layer. There are plenty of frameworks lately, to organize and potencialize the web client tier, and consequently, difficulty in dealing with all of this information. The framework selection process, from a developer¿s perspective, can be pragmactic, a denial of choice, or the creation of a new option, specific to his problem. The lack of an accessible body of knowledge hinders the learning process and the engagement of the profissionals on reusing the best practices in their projects. Based on the analysis of web architectures on the client side and systematic review of the state of art on the empirical methods of software component¿s selection, this dissertation presents the results of a research conducted with 26 technology professionals and 3 usability specialists. They used a prototype of an application built for this research, for experimentation and solutions composition from code fragments, employing different frameworks. The objective of this experiment was to map the needs of a system that approaches the practical frameworks selection process, and map how a group of professionals involved with computing would use this kind of tool. According to the study, code demonstrations are the most helpful information source for framework adoption and code fragments exert proven influence in the final code of this kind of application. The diferential of the proposed knowledge base is its capacity to integrate codes, assessments and performance analysis, aiming to create code patterns for learning or immediate usage. The use of a functional prototype and the precocious evolvement of end users in usability tests was very positive for eliciting a complete list of functional and non-functional requirements for this tool.
132

Construction de systèmes répartis sécurisés à base de composants / Tools' design and development for building secure component-based distributed systems

Youssef, Lilia 12 May 2012 (has links)
L'objectif de ce travail est de fournir des modèles et outils pour simplifier la construction des systèmes distribués à base de composants sécurisés, ainsi que la gestion des propriétés de sécurité, en utilisant des outils de haut niveau d'abstraction pour la configuration et la reconfiguration dynamique. En plus des propriétés d'accessibilité et de communications sécurisées classiques, nous focalisons notre travail sur une propriété des systèmes répartis plus générale : la non-interférence. Cette propriété atteste qu'il ne doit pas y avoir de flux d'information entre des parties publiques et privées du système. Ce qui implique le suivi de l'acheminement de l'information entre les différentes composantes du système distribué. Notre objectif principal est donc de proposer un modèle, accompagné d'un ensemble d'outils, garantissant la propriété de la non-interférence à la construction du système, et ce à une plus grosse granularité : celle des composants. Ces outils permettent de (1) configurer les paramètres de sécurité des composants et des liaisons entre eux, (2) vérifier la propriété de non-interférence dans le code d'un composant et entre les différents composants du système et (3) générer automatiquement le code nécessaire pour appliquer ces propriétés de sécurité. D'autre part, nous proposons une architecture permettant de vérifier dynamiquement la propriété de non-interférence dans un système réparti. / The goal of this thesis is to provide models and tools to simplify secured component-based distributed systems' construction and the management of their security properties, by using high-level tools for dynamic configuration and reconfiguration. In addition to the classic properties of accessibility and secured communications, we focus on a more general security property of distributed systems : the non-interference. This property says that there mustn't be information flow between secret and public parts of the system ; which requires information flow control across the system. Our main objective is to propose a model and set of tools guarantying the non-interference property at compiletime, and at a bigger granularity : the components. These tools are (1) tools for configuring security parameters of components and binding between components, (2) a compiler checking the non-interference property, and (3) tools for automatic generation of code assuring these security properties. On the other hand, we present an architecture enabling a dynamic verification of the non-interference property in a distributed system.
133

Implémentation rigoureuse des systèmes temps-réels / Rigorous Implementation of Real-Time Systems

Abdellatif, Tesnim 05 June 2012 (has links)
Les systèmes temps-réels sont des systèmes qui sont soumis à "des contraintes de temps", comme par exemple le délais de réponse d'un système à un événement physique. Souvent les temps de réponse sont de l'ordre du milliseconde et parfois même du microseconde. Construire des systèmes temps-réels nécessite l'utilisation de méthodologies de conception et de mise en œuvre qui garantissent la propriété de respect des contraintes de temps, par exemple un système doit réagir dans les limites définies par l'utilisateur tels que les délais et la périodicité. Un délai non respecté dans systèmes temps-réel critique est catastrophique, comme par exemple dans les systèmes automobiles. Si un airbag se déclanche tard dans un accident de voiture, même quelques millisecondes trop tard peuvent conduire à des répercussions graves. Dans les systèmes temps-réels non critiques, une perte significative de performance et de QoS peuvent se produire, comme par exemple dans les réseaux de systèmes multimédia. Contribution: Nous fournissons une méthode de conception rigoureuse des systèmes temps-réel. L'implèmentation est générée à partir d'une application logicielle temps-réel et une plate-forme cible, en utilisant les deux modèles suivants: * Un modèle abstrait représentant le comportement de l'application logicielle en temps réel sous forme d' un automate temporisé. Celui-ci décrit des contraintes temporelles définies par l'utilisateur qui sont indépendantes de la plateforme. Ses transitions sont intemporelles et correspondent à l'exécution des différentes instructions de l'application. * Un modèle physique représentant le comportement du logiciel en temps réel s'exécutant sur une plate-forme donnée. Il est obtenu par l'attribution des temps d'exécution aux transitions du modèle abstrait. Une condition nécessaire pour garantir l'implémentabilité dy système est la "time-safety", c'est à dire, toute séquence d'exécution du modèle physique est également une séquence d'exécution du modèle abstrait. "Time-safety" signifie que la plate-forme est assez rapide pour répondre aux exigences de synchronisation de l'application. Comme les temps d'exécution des actions ne sont pas connus avec exactitude, "time-safety" est vérifiée pour les temps d'exécution pire cas es actions en faisant l' hypothèse de la robustesse. La robustesse signifie que la "time-safety" est préservée lorsqu'on augmente la vitesse de la plate-forme d'exécution. Pour des logiciels et plate-forme d'exécution correspondant à un modèle robuste, nous définissons un moteur d'exécution qui coordonne l'exécution du logiciel d'application afin de répondre à ses contraintes temporelles. En outre, en cas de non-robustesse, le moteur d'exécution permet de détecter les violations de contraintes temporelles en arrêtant l'exécution. Nous avons mis en place le moteur d'exécution pour les programmes BIP. Nous avons validé la méthode pour la conception et la mise en œuvre du robot Dala. Nous montrons les avantages obtenus en termes d'utilisation du processeur et l'amélioration de la latence de la réaction. / Context: Real-time systems are systems that are subject to "real-time constraints"— e.g. operational deadlines from event to system response. Often real-time response times are understood to be in the order of milliseconds and sometimes microseconds. Building real-time systems requires the use of design and implementation methodologies that ensure the property of meeting timing constraints e.g. a system has to react within user-defined bounds such as deadlines and periodicity. A missed deadline in hard real-time systems is catastrophic, like for example in automotive systems, for example if an airbag is fined too late in a car accident, even one ms too late leads to serious repercussions. In soft real-time systems it can lead to a significant loss of performance and QoS like for example in networked multimedia systems. Contribution: We provide a rigorous design and implementation method for the implementation of real-time systems. The implementation is generated from a given real-time application software and a target platform by using two models: * An abstract model representing the behavior of real-time software as a timed automaton. The latter describes user-defined platform-independent timing constraints. Its transitions are timeless and correspond to the execution of statements of the real-time software. * A physical model representing the behavior of the real-time software running on a given platform. It is obtained by assigning execution times to the transitions of the abstract model. A necessary condition for implementability is time-safety, that is, any (timed) execution sequence of the physical model is also an execution sequence of the abstract model. Time-safety means that the platform is fast enough to meet the timing requirements. As execution times of actions are not known exactly, time-safety is checked for worst-case execution times of actions by making an assumption of time-robustness: time-safety is preserved when speed of the execution platform increases. For given real-time software and execution platform corresponding to a time-robust model, we define an execution Engine that coordinates the execution of the application software so as to meet its timing constraints. Furthermore, in case of non-robustness, the execution Engine can detect violations of time-safety and stop execution. We have implemented the execution Engine for BIP programs with real-time constraints. We have validated the method for the design and implementation of the Dala rover robot. We show the benefits obtained in terms of CPU utilization and amelioration in the latency of reaction.
134

Déploiement d’applications patrimoniales en environnements de type informatique dans le nuage / Deploying legacy applications in cloud computing environments

Etchevers, Xavier 12 December 2012 (has links)
L'objectif de cette thèse est d'offrir une solution de bout en bout permettant de décrire et de déployer de façon fiable une application distribuée dans un environnement virtualisé. Ceci passe par la définition d'un formalisme permettant de décrirer une application ainsi que son environnement d'exécution, puis de fournir les outils capable d'interpéter ce formalisme pour déployer (installer, instancier et configurer) l'application sur une plate-forme de type cloud computing. / Cloud computing aims to cut down on the outlay and operational expenses involved in setting up and running applications. To do this, an application is split into a set of virtualized hardware and software resources. This virtualized application can be autonomously managed, making it responsive to the dynamic changes affecting its running environment. This is referred to as Application Life-cycle Management (ALM). In cloud computing, ALM is a growing but immature market, with many offers claiming to significantly improve productivity. However, all these solutions are faced with a major restriction: the duality between the level of autonomy they offer and the type of applications they can handle. To address this, this thesis focuses on managing the initial deployment of an application to demonstrate that the duality is artificial. The main contributions of this work are presented in a platform named VAMP (Virtual Applications Management Platform). VAMP can deploy any legacy application distributed in the cloud, in an autonomous, generic and reliable way. It consists of: • a component-based model to describe the elements making up an application and their projection on the running infrastructure, as well as the dependencies binding them in the applicative architecture; • an asynchronous, distributed and reliable protocol for self-configuration and self-activation of the application; • mechanisms ensuring the reliability of the VAMP system itself. Beyond implementing the solution, the most critical aspects of running VAMP have been formally verified using model checking tools. A validation step was also used to demonstrate the genericity of the proposal through various real-life implementations.
135

CHROME: a model-driven component-based rule engine

Vitorino dos Santos Filho, Jairson 31 January 2009 (has links)
Made available in DSpace on 2014-06-12T15:51:39Z (GMT). No. of bitstreams: 2 arquivo2757_1.pdf: 5759741 bytes, checksum: 8075c58c36a6d409b242f2a7873fb02f (MD5) license.txt: 1748 bytes, checksum: 8a4605be74aa9ea9d79846c1fba20a33 (MD5) Previous issue date: 2009 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / Vitorino dos Santos Filho, Jairson; Pierre Louis Robin, Jacques. CHROME: a model-driven component-based rule engine. 2009. Tese (Doutorado). Programa de Pós-Graduação em Ciência da Computação, Universidade Federal de Pernambuco, Recife, 2009.
136

Towards Model-Driven Engineering Constraint-Based Scheduling Applications

de Siqueira Teles, Fabrício 31 January 2008 (has links)
Made available in DSpace on 2014-06-12T15:57:08Z (GMT). No. of bitstreams: 2 arquivo3142_1.pdf: 2136149 bytes, checksum: 9584d05181d7f6e862c757ce418c8701 (MD5) license.txt: 1748 bytes, checksum: 8a4605be74aa9ea9d79846c1fba20a33 (MD5) Previous issue date: 2008 / de Siqueira Teles, Fabrício; Pierre Louis Robin, Jacques. Towards Model-Driven Engineering Constraint-Based Scheduling Applications. 2008. Dissertação (Mestrado). Programa de Pós-Graduação em Ciência da Computação, Universidade Federal de Pernambuco, Recife, 2008.
137

Service-Oriented Integration of Component and Organizational MultiAgent Models / Intégration orientée services des approches composants logiciels et systèmes MultiAgents Organisationnelles

Aboud, Nour 04 December 2012 (has links)
Les travaux présentés dans cette thèse concernent des problématiques d'architecture logicielle multi-domaines pour le développement d’applications distribuées. Ces applications sont caractérisées aujourd’hui comme des systèmes ouverts, complexes, hétérogènes et à large échelle. Les approches traditionnelles, telles que l’approche orienté objet, n’offrent plus un paradigme de conception suffisant pour appréhender la complexité de tels systèmes. Ces nouvelles tendances ont conduit à l’émergence d’approches de plus haut niveau telles que les approches orientées services, composants ou agents. Chacune de ces approches offrent des intérêts et des caractéristiques propres dans le développement d’applications distribuées. Les services offrent une abstraction et une interopérabilité à large échelle. Abstraction dans le sens où un service permet de spécifier un élément fonctionnel sans préciser comment cet élément est implémenté. Les composants sont une approche robuste basée sur la composition et la réutilisation d’éléments clairement définis par leurs interfaces. Les agents sont eux des éléments présentant un comportement dynamique dirigé par un but et des interactions de haut niveau avec les autres agents formant l’application, vue comme une organisation de services collaboratifs. D’un point de vue conceptuel, le service peut donc être perçu comme le modèle « métier » de l’application, alors que les composants et les agents constituent un modèle d’implémentation. L’étude de ces différents domaines et des modèles associés, a montré que les approches composants et agents sont complémentaires, les points forts d’une approche représentant les faiblesses de l’autre. Face à ce constat, il nous est paru intéressant d’intégrer ces deux approches, au sein d’une même démarche de conception. Cela permet, d’une part, qu’une approche puisse bénéficier des intérêts de l’autre et d’autre part, d’utiliser conjointement des agents et des composants dans la conception d'une même application. La démarche que nous avons adoptée consiste à considérer les services comme pivot d’interaction afin de rendre possible l’interopérabilité des agents et des composants. Pour supporter cette démarche, nous avons défini un processus de conception basé sur l’Ingénierie Des Modèles qui contient quatre modèles conceptuels (Domain Specific language) dont l’intérêt est de mettre l’accent sur les concepts de services et d’interaction. Nous avons ainsi défini un modèle de services, un modèle de composants et un modèle d’agents. Enfin, un modèle mixte appelé CASOM, Component Agent Service Oriented Model, permet de spécifier une application via une combinaison des trois domaines précédents. Ensuite, des règles de correspondances ont été définies entre les quatre modèles pour pouvoir par exemple transformer une spécification agents en une spécification composants ou mixte. L'implémentation de ces transformations a été réalisée en langage ATL (ATLAS Transformation Language). / The presented work considers problems related to multi-domain software architecture for the development of distributed applications. These applications are large-scaled, heterogeneous, open and complex software systems. Traditional approaches such as object-oriented are no longer sufficient to represent such complex systems. These trends lead to the emergence of higher-level approaches such as service-oriented, components or agents. Each one of these approaches offers interests and characteristics in the development of distributed applications. Services provide an abstraction and interoperability in a large scale. Abstraction is in the sense that a service can specify a functional element without specifying how this element is implemented. The components are a robust approach based on composition and reusability through their clearly defined interfaces. Agents are elements which are characterized by dynamic goal directed behaviours and high-level interactions with other agents forming the application, seen as an organization for collaborative services. From a conceptual point of view, the service can be seen as the “business” model of an application, while components and agents are the implementation models. The study of these different domains, with their related models, showed that the components and agents approaches are complementary; the strengths of one approach overcome the weaknesses of the other. Therefore, we are interested in the integration of these two approaches in a single design approach. This allows an approach to benefit from the interests of the other, on one hand and the use of agents and components jointly in the design of an application on the other hand. To reach our objective, we consider services as pivot of interaction between agents and components. The result of our analysis leads us to develop a design process based on Model-Driven Engineering which contains four conceptual models (Domain Specific Languages) with the main interest of focusing on the concepts of services and interaction. We then defined a service, component and agent models. Finally, a hybrid model called CASOM, Component Agent Service Oriented Model, was proposed that allows application specification via a combination of the three domains. Then, mapping rules have been defined between the four models in order to transform agents specification into components specification or mixed. The implementation of these transformations was done in ATL language (ATLAS Transformation Language).
138

Generella krav : Modell för generalisering av krav

Lindeberg, Eric, Larsson, Petter January 2017 (has links)
I det här arbetet har vi undersökt hur man kan generalisera en samling krav för att därigenom generalisera det system som kraven ligger till grund för. På det sättet kan man göra ett system tillämpbart över fler användningsområden än det ursprungligen var avsett för. Vi har utvecklat två artefakter i form av en stegmodell och en prototyp för att uppnå detta.
139

Aspect Analyzer: Ett verktyg för automatiserad exekveringstidsanalys av komponenter och aspekter / Aspect Analyzer: A Tool for Automated WCET Analysis of Aspects and Components

Uhlin, Pernilla January 2002 (has links)
The increasing complexity in the development of a configurable real-time system has emerged new principles of software techniques, such as aspect-oriented software development and component-based software development. These techniques allow encapsulation of the system's crosscutting concerns and increase the modularity of the software. The properties of a component that influences the systems performance or semantics are specified separately in entities called aspects, while basic functionality of the property still remains in the component. When building a real-time system, different sets of configurations of aspects and components can be combined, resulting in different configurations of the system. The temporal behavior of the system changes and a way to ensure the predictability of the system is needed. This thesis presents a tool for aspect-level worst-case execution time analysis, which gives a priori information about the temporal behavior of the system, before the process of composing aspects with components.
140

Verifikation av verktyget aspect analyzer / Aspect analyzer tool verification

Bodin, Joakim January 2003 (has links)
Rising complexity in the development of real-time systems has made it crucial to have reusable components and a more flexible way of configuring these components into a coherent system. Aspect-oriented system development (AOSD) is a technique that allows one to put a system’s crosscutting concerns into"modules"that are called aspects. Applying AOSD in real-time and embedded system development one can expect reductions in the complexity of the system design and development. A problem with AOSD in its current form is that it does not support predictability in the time domain. Hence, in order to use AOSD in real-time system development, we need to provide ways of analyzing temporal behavior of aspects, components and resulting system (made from weaving aspects and components). Aspect analyzer is a tool that computes the worst-case execution time (WCET) for a set of components and aspects, thus, enabling support for predictability in the time domain of aspect-oriented real-time software. A limitation of the aspect analyzer, until now, were that no verification had been made whether the aspect analyzer would produce WCET values that were close to the measured or computed (with another WCET analysis technique) WCET of an aspect-oriented real-time system. Therefore, in this thesis we perform a verification of the correctness of the aspect analyzer using a number of different methods for WCET analysis. These investigations of the correctness of the output from the aspect analyzer gave confidence to the automated WCET analysis. In addition, performing this verification led to the identification of the steps necessary to compute the WCETs of a piece of program, when using a third party tool, which gives the ability to write accurate input files for the aspect analyzer.

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