A presente tese de doutorado está inserida dentro do contexto da área de AOSE – Agent-Oriented Software Engineering, uma área surgida recentemente voltada para a engenharia de software de sistemas multi-agentes que mescla conceitos tanto da Inteligência Artificial como da Engenharia de Software. Esta nova área surgiu devido aos novos desafios enfrentados pelos engenheiros de software ao projetar sistemas multi-agentes, uma vez que este tipo de sistema apresenta características que os diferenciam de outros tipos de software, precisamente o fato de possuírem agentes de software, entidades autônomas e pró-ativas que executam funções no sistema, possuidoras de objetivos próprios e capazes de perceber e agir sobre o ambiente que os cerca sem a intervenção de usuários externos. Este trabalho descreve um metamodelo UML desenvolvido para a modelagem de requisitos funcionais específicos para projetos de sistemas multi-agentes. O seu desenvolvimento baseou-se na constatação de que, apesar de já existirem linguagens derivadas da UML para o projeto de sistemas multi-agentes, nenhuma das linguagens estudadas desenvolveu mecanismos para a modelagem dos requisitos deste tipo de software, o que levou-nos a criar um metamodelo UML para este propósito. No decorrer desta tese serão descritas as linguagens estudadas derivadas da UML para ser aplicadas no projeto de sistemas multi-agentes, o metamodelo desenvolvido, sua adaptação aos princípios de projeto de Vicari (2007), três estudos de caso onde o metamodelo foi aplicado, além de uma proposta de mapeamento dos conceitos definidos no metamodelo para os conceitos das linguagens MAS-ML e AML, bem como uma proposta para a validação do metamodelo e dos diagramas criados por meio dele. / This PhD thesis is inserted within the context of the AOSE (Agent-Oriented Software Engineering) area, a recently-emerged field dealing with the software engineering of multi-agent systems which mixes concepts of Artificial Intelligence and Software Engineering together. This new area emerged from new challenges faced by the software engineers when designing multi-agent systems, since this kind of system presents characteristics that set them apart from other types of software, precisely for including software agents, autonomous and proactive entities that execute functions in the system, owning their own goals and able to perceive and act upon the surrounding environment without the intervention of external users. This work describes a UML metamodel developed for the modeling of the specific functional requirements for multi-agent systems projects. Its development was based on the perception that among the studied UML-derived languages for the multi-agent systems project, none of them had developed mechanisms for requirements modeling on this kind of software, leading us to create a UML metamodel for this purpose. Along this thesis we shall describe the UML-derived languages we studied to be applied in the multi-agent systems project, the developed metamodel, its adaptation to the Vicari (2007) design principles, three case studies on which the metamodel was applied, plus a mapping proposal for the concepts defined in the metamodel into MASML and AML languages concepts, as well as a validation proposal for the metamodel and the diagrams created by means of it.

A presente tese de doutorado está inserida dentro do contexto da área de AOSE – Agent-Oriented Software Engineering, uma área surgida recentemente voltada para a engenharia de software de sistemas multi-agentes que mescla conceitos tanto da Inteligência Artificial como da Engenharia de Software. Esta nova área surgiu devido aos novos desafios enfrentados pelos engenheiros de software ao projetar sistemas multi-agentes, uma vez que este tipo de sistema apresenta características que os diferenciam de outros tipos de software, precisamente o fato de possuírem agentes de software, entidades autônomas e pró-ativas que executam funções no sistema, possuidoras de objetivos próprios e capazes de perceber e agir sobre o ambiente que os cerca sem a intervenção de usuários externos. Este trabalho descreve um metamodelo UML desenvolvido para a modelagem de requisitos funcionais específicos para projetos de sistemas multi-agentes. O seu desenvolvimento baseou-se na constatação de que, apesar de já existirem linguagens derivadas da UML para o projeto de sistemas multi-agentes, nenhuma das linguagens estudadas desenvolveu mecanismos para a modelagem dos requisitos deste tipo de software, o que levou-nos a criar um metamodelo UML para este propósito. No decorrer desta tese serão descritas as linguagens estudadas derivadas da UML para ser aplicadas no projeto de sistemas multi-agentes, o metamodelo desenvolvido, sua adaptação aos princípios de projeto de Vicari (2007), três estudos de caso onde o metamodelo foi aplicado, além de uma proposta de mapeamento dos conceitos definidos no metamodelo para os conceitos das linguagens MAS-ML e AML, bem como uma proposta para a validação do metamodelo e dos diagramas criados por meio dele. / This PhD thesis is inserted within the context of the AOSE (Agent-Oriented Software Engineering) area, a recently-emerged field dealing with the software engineering of multi-agent systems which mixes concepts of Artificial Intelligence and Software Engineering together. This new area emerged from new challenges faced by the software engineers when designing multi-agent systems, since this kind of system presents characteristics that set them apart from other types of software, precisely for including software agents, autonomous and proactive entities that execute functions in the system, owning their own goals and able to perceive and act upon the surrounding environment without the intervention of external users. This work describes a UML metamodel developed for the modeling of the specific functional requirements for multi-agent systems projects. Its development was based on the perception that among the studied UML-derived languages for the multi-agent systems project, none of them had developed mechanisms for requirements modeling on this kind of software, leading us to create a UML metamodel for this purpose. Along this thesis we shall describe the UML-derived languages we studied to be applied in the multi-agent systems project, the developed metamodel, its adaptation to the Vicari (2007) design principles, three case studies on which the metamodel was applied, plus a mapping proposal for the concepts defined in the metamodel into MASML and AML languages concepts, as well as a validation proposal for the metamodel and the diagrams created by means of it.

Made available in DSpace on 2016-08-17T14:53:18Z (GMT). No. of bitstreams: 1 Eduardo Devidson Costa Bezerra.pdf: 6161794 bytes, checksum: 61fa31f8c5757b2b771df924fa5e9483 (MD5) Previous issue date: 2011-07-29 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / The use of the Internet as a way to publish new applications and deliver new functionalities has consolidated the use of web services technology. Once web services technology enables a high degree of autonomy and interoperability, it provides a basic infrastructure for the development and composition of new services, which has benefited the business process management providing the agility required by enterprises to meet the need of rapidly changing business environment. Recently, new paradigms are being developed to deal with the increasing complexity in the development, maintenance and evolution of software systems. Among the new paradigms, Model Driven Engineering (MDE) and the Ontology stands out as the most promising for handling complex software systems. This work presents an approach to perform the dynamic composition of web services using techniques of match models (metamodels) that represent services. Models representing services must include semantic and structural aspects of the web service achieved through approaches to ontologies. Thus, we conjecture to establish matchings and measure the degree of similarity between models and investing in research about Ontologies and MDE in order to generate a tool that can assist in a Dynamic Composition of Web Services. A case study is presented to illustrate this approach. / A utilização da internet como forma de publicar novas aplicações e disponibilizar novas funcionalidades tem consolidado o uso da tecnologia de serviços web. Uma vez que essa tecnologia viabiliza um alto grau de interoperabilidade e autonomia, a tecnologia de serviços web fornece uma infra-estrutura básica para o desenvolvimento e a composição de novos serviços, o que tem beneficiado à gerência de processos de negócio oferecendo assim, a agilidade necessária e requerida pelos empreendimentos frente à necessidade de rápidas mudanças no ambiente de negócios. Recentemente, novos paradigmas vêm sendo desenvolvidos para fazerem face à complexidade cada vez mais crescente no desenvolvimento, manutenção e evolução de softwares. Dentre eles a Engenharia Dirigida por Modelos (MDE Model Driven Engineering) e as Ontologias se destacam como os mais promissores. Neste trabalho, apresenta-se uma abordagem para realizar a composição dinâmica de um novo serviço web utilizando técnicas de Matching de modelos (ou metamodelos) que representem serviços. Tal representação deverá conter aspectos semânticos e estruturais do serviço web conseguidos através de abordagens de Ontologias. Sendo assim, vislumbra-se estabelecer correspondências e medir o grau de similaridade entre modelos investindo na pesquisa de MDE e Ontologias com o intuito de gerar uma ferramenta que possa auxiliar na Composição Dinâmica de um Serviço. Para validar a abordagem, um estudo de caso será apresentado.

Les Matrices de Comparaison de Produits (MCP) sont largement répandues sur le web. Elles fournissent une représentation simple des caractéristiques d'un ensemble de produits. Cependant, le manque de formalisation et la grande diversité des MCP rendent difficile le développement de logiciels pour traiter ces matrices. Dans cette thèse, nous développons deux approches complémentaires pour la formalisation de MCP. La première consiste en une description précise de la structure et la sémantique d'une MCP sous la forme d'un meta-modèle. Nous proposons aussi une transformation automatique d'une MCP vers un modèle de MCP conforme au meta-modèle. La seconde approche consiste à synthétiser des modèles de caractéristiques attribués à partir d'une classe de MCP. Grâce nos contributions, nous proposons une approche générique et extensible pour la formalisation et l'exploitation de MCP. / Product Comparison Matrices (PCMs) abound on the Web. They provide a simple representation of the characteristics of a set of products. However, the lack of formalization and the large diversity of PCMs challenges the development of software for processing these matrices. In this thesis, we develop two complementary approaches for the formalisation of PCMs. The first one consists in a precise description of the structure and semantics of PCMs in the form of a metamodel. We also propose an automated transformation from PCMs to PCM models conformant to the metamodel. The second one consists in synthesizing attributed feature models from a class of PCMs. With our contributions, we propose a generic and extensible approach for the formalization and exploitation of PCMs.

In this thesis, the authors investigate how machine learning can be utilized for speeding up the design optimization process of gas turbines. The Finite Element Analysis (FEA) steps of the design process are examined if they can be replaced with machine learning algorithms. The study is done using a component with given constraints that are provided by Siemens Energy AB. With this component, two approaches to using machine learning are tested. One utilizes design parameters, i.e. raw floating-point numbers, such as the height and width. The other technique uses a high dimensional mesh as input. It is concluded that using design parameters with surrogate models is a viable way of performing design optimization while mesh input is currently not. Results from using different amount of data samples are presented and evaluated.

Dans un contexte de réduction des impacts des pratiques agricoles sur la santé humaine et sur les écosystèmes, il est nécessaire de bien prendre en compte la volatilisation d’ammoniac (NH3) dans les inventaires d’émissions, la compréhension du devenir de l’azote après fertilisation et la modélisation de la qualité de l’air. Etant donné le poids de la fertilisation azotée (55%) dans le total des émissions nationales de NH3, cette dernière constitue un levier important pour réduire les émissions de NH3. Les inventaires nationaux actuels, basés sur l’utilisation de facteurs d’émission par défaut, souffrent d’un manque de description spatiale et temporelle, rendant difficile l’élaboration des politiques de réduction efficaces des émissions. Par ailleurs, même s’il existe à l’heure actuelle des modèles qui simulent de manière globale le devenir de l’azote sur le cycle de la culture, la volatilisation de NH3 n’est pas toujours prise en compte, et si elle l’est, les modules de volatilisation sont souvent relativement frustres et n’ont été que partiellement validés. Il existe pourtant des modèles dédiés exclusivement à la volatilisation de NH3 au champ, mais leurs exigences en données et paramètres d’entrée et leur temps de calcul limitent leur utilisation à grande échelle (exemple, échelle nationale…) sur de nombreux sites géographiques pendant plusieurs années, ainsi que leur intégration dans des modèles opérationnels de prédiction de la qualité de l’air, ou des outils d’aide à la décision ou d’évaluation environnementale en termes de fertilisation azotée.Cette thèse propose des nouveaux outils. Le premier outil, CADASTRE_NH3, permet de décrire et d’analyser la variabilité spatio-temporelle des émissions de NH3 liées à la fertilisation azotée. Il couple le modèle de processus Volt’Air avec des bases de données géo-référencées sur les facteurs agro-pédoclimatiques à l’échelle nationale. Cette approche d’inventaires des émissions a montré sa capacité à capturer les variabilités spatio-temporelles de l’utilisation d’azote et des émissions de NH3 qui en résultent, et à prendre en compte l’effet des interactions des facteurs pédologiques et/ou climatiques sur les émissions. La confrontation des résultats de l’outil CADASTRE_NH3 avec les inventaires officiels français montrent de fortes convergences en ce qui concerne les quantités d’azote utilisé et les émissions de NH3 en France pour l’année 2005-06, mais aussi des divergences notamment pour le cas des produits résiduaires organiques. Le deuxième type d’outils correspond aux méta-modèles dérivés de Volt'Air pour prédire les taux d’émissions de NH3 après application d’engrais azotés. Ces méta-modèles présentent de nombreux avantages pratiques du fait de leur simplicité et opérationnalité. Ils ont des potentiels d’utilisation prometteurs pour accompagner la prise de décision en terme de conditions d’utilisation des engrais et également pour appuyer les politiques de réduction des émissions à travers par exemple la réalisation des tests de scénarios.Il serait cependant intéressant de confronter les outils développés dans le cadre de cette thèse avec des données expérimentales pour évaluer leur performance respective et valider l’ensemble de nos approches. Il serait également intéressant de développer des méta-modèles dynamiques dérivés du modèle Volt’Air capables de décrire la dynamique des flux de NH3 liés à l’application des engrais azotés pour être intégrés comme modules simples de volatilisation de NH3 dans des modèles agronomiques et atmosphériques. / In a context of reducing the impacts of agricultural practices on human health andecosystems, it is necessary to better account for ammonia (NH3) volatilization in the inventories of NH3 emissions, the understanding of the nitrogen behavior after fertilization and the modeling of air quality.Given the considerable weight of nitrogen fertilizer (55%) in the total national NH3 emissions, nitrogen fertilization is an important lever for reducing NH3 emissions. Current national inventories are based on the use of default emission factors (EF) and suffer from a lack of fine spatial and temporal NH3 emissions descriptions making it difficult to develop effective emission reduction policies. Moreover, even if there are currently models that globally simulate the fate of nitrogen on the crop cycle, their do not always take into account the volatilization of NH3, and if it is, the volatilization modules are often very frustrating and have not been validated. There are models dedicated exclusively to the volatilization of NH3 in the field, but their requirements for data and input parameters and their calculation time limit their large-scale use (e.g, at national scale) in many geographical locations for several years as well as their integration into airquality prediction models or decision support or environmental assessment tools in terms of nitrogen fertilization.This thesis proposes new tools. The first tool, CADASTRE_NH3 makes it possible to describe and analyze the spatio-temporal variability of NH3 emissions from nitrogen fertilization. It combines the Volt'Air process-based model with geo-referenced databases on agro-soil-meteorological factors at the national level. This approach has demonstrated its ability to capture the spatio-temporal variability ofnitrogen use and resulting NH3 emissions, and to take into account the effect of soil and climate factor interactions on emissions. The comparison of CADASTRE_NH3 results with the official French inventories shows strong convergences regarding the quantities of nitrogen used and NH3 emissions in France for the year 2005-06, but also divergences especially for the case of organic waste products. Thesecond type of tool corresponds to meta-models derived from Volt'Air for predicting NH3 emission rates after nitrogen fertilizer applications. These meta-models have many practical advantages because of their simplicity and operability. They have promising potential uses to support decision-making in terms of fertilizer use conditions and also to support emission reduction policies through, for example, scenario testing.However, it would be interesting to compare the tools developed in this thesis with experimental data to evaluate their respective performance and validate all our approaches. It would also be interesting to develop dynamic meta-models of Volt'Air that can describe the dynamics of NH3 fluxes related to nitrogen fertilizer applications and to be integrated as simple modules of NH3 volatilization in agronomic and atmospheric models.

Melhoria de processo de software (SPI) é uma prática de engenharia de software motivada pela necessidade de aumentar a qualidade e a produtividade no desenvolvimento de software. Um fato amplamente reconhecido é que a qualidade do produto de software pode ser, em grande parte, determinada pela qualidade do processo utilizado para desenvolvê-lo e mantê-lo. A avaliação do processo de software ajuda as organizações de software a amadurecerem seus processos, identificando problemas críticos para estabelecer prioridades de melhoria. Essa avaliação pode ser feita por meio da comparação do estado dos processos da organização em relação a um modelo de referência que estabeleça estágios de melhoria. Uma avaliação geralmente se baseia em um modelo de processo de software que fornece um roteiro para melhorias. Este trabalho tem como objetivo estabelecer uma abordagem que: (i) define um conjunto de modelos de abstração (metamodelos) de modelos de maturidade de processo de software para apoiar uma metodologia de avaliação/melhoria de processo de software com o objetivo de certificação; e (ii) permite avaliar os processos de uma organização em comparação com um modelo de maturidade por meio de transformações desses metamodelos. A abordagem é instanciada por meio de um estudo de caso utilizando os modelos MPS.Br e CMMI para exemplificar sua aplicação. Como resultado, é apresentado um comparativo entre as limitações encontradas nas metodologias encontradas na literatura e como a abordagem sugere superá-las. / Software process improvement (SPI) is a software engineering practice motivated by the need to increase the quality and productivity in software development. A fact widely recognized is that the quality of the software product can be largely determined by the quality of the process used to develop and maintain it. The assessment of software process helps software organizations to improve themselves, identifying their critical problems to establish priorities for improvement. This assessment can take place by comparing the state of the organization on their software processes to a reference model that shows stages of improvement in scales. An assessment is usually based on a software process model that provides a roadmap for improvement. This work aims to establish an approach that: (i) defines a set of abstraction models (metamodels) of software process maturity models to support an assessment/improvement methodology aiming software process certification; and (ii) evaluates the organization processes in comparison with the maturity models through transformations of those metamodels. The approach is instantiated through a case study using the MPS.Br and CMMI models to illustrate its application. As a result, a comparison between the limitations found in the methodologies identified in the literature and how the approach suggested overcome them is presented.

Les systèmes embarqués tels que les téléphones portables ou les lecteurs multimédia intègrent de plus en plus de fonctions consommatrices d'énergie ce qui a pour conséquence directe une diminution de leurs autonomies. Les applications audio dans les téléphones cellulaires et en particulier l'application casque font partie des fonctions les plus consommatrices d'énergie. Après un état de l'art des solutions permettant l'amplification de signaux audio, l'amplificateur de classe G à été identifié comme étant le meilleur candidat pour obtenir une amélioration du rendement tout en fournissant une bonne qualité de reproduction sonore. Nos travaux se sont plus particulièrement focalisés sur la détection d'enveloppe de ces architectures qui est un facteur clé dans la maximisation du rendement. Une étude des propriétés temporelles, fréquentielles et statistiques des signaux présents en entrée de l'amplificateur a ainsi été menée pour mettre en évidence les différences entre les signaux classiquement utilisés (signal sinusoïdal) et les signaux réellement écoutés par les utilisateurs (musique). Après avoir effectué une sélection de signaux pour la suite de notre étude, nous avons également caractérisé la puissance correspondant à des conditions normales d'écoute afin d'obtenir par la suite un environnement de test proche des conditions réelles de fonctionnement. Un modèle simplifié et rapide d'amplificateur hybride permettant d'obtenir en quelques dizaines de secondes, l'évaluation du rendement, de la consommation et de la qualité sonore dans des conditions réelles de fonctionnement a été développé. Notre modèle, entièrement configurable et réadaptable à d'autres types de circuits a été validé par mesures pratiques des performances d'un amplificateur existant. Les paramètres de la détection d'enveloppe de ce modèle ont fait l'objet d'une optimisation basée sur le couplage séquentiel de deux algorithmes d'optimisation, permettant ainsi dans un temps limité d'obtenir une solution optimale sans solution de départ sous des conditions réelles d'utilisation. La suite de notre étude nous a conduit à étudier, modéliser, optimiser et comparer des amplificateurs de classe G possédant un nombre de tensions d'alimentation supérieur (3, 4) ainsi que des amplificateurs de classe H (alimentations continues) afin d'améliorer encore le rendement. Enfin, nous avons proposé une nouvelle détection d'enveloppe permettant d'améliorer le rendement à faible puissance. Cette nouvelle détection d'enveloppe permet à l'amplificateur de classe G un fonctionnement en « multi niveau » et d'être auto adaptatif au signal audio présent en entrée de l'amplificateur. Après avoir développé des méta-modèles pour optimiser les paramètres de la détection d'enveloppe, cette détection d'enveloppe a été implémentée au niveau transistor en technologie 0.25μm de ST Microelectronics. / Embedded systems such as mobile phones, tablets and GPS incorporate an increasing number of electronic functions that generate a decrease in battery life. The aim of this work is to propose new solutions for audio amplifiers for the headphone application because this application has a large impact on battery autonomy. To improve the efficiency of actual amplifiers, a behavioral model of this kind of amplifier has been developed and validated by practical measures. This model, fast, accurate and reconfigurable allows in few seconds to evaluate the efficiency, consumption and quality of sound reproduction in real conditions of operation. Through the use of this model coupled with an optimizing method based on two algorithms, several architectures of level detector were studied and compared allowing to define the best compromise. A new architecture is then proposed, simulated and optimized in a 0.25μm technology from ST Microelectronics to demonstrate the feasibility of the solution.

The use of computer modeling is fast increasing in almost every scientific, engineering and business arena. This dissertation investigates some challenging issues in design, modeling and analysis of computer experiments, which will consist of four major parts. In the first part, a new approach is developed to combine data from approximate and detailed simulations to build a surrogate model based on some stochastic models. In the second part, we propose some Bayesian hierarchical Gaussian process models to integrate data from different types of experiments. The third part concerns the development of latent variable models for computer experiments with multivariate response with application to data center temperature modeling. The last chapter is devoted to the development of nested space-filling designs for multiple experiments with different levels of accuracy.

Melhoria de processo de software (SPI) é uma prática de engenharia de software motivada pela necessidade de aumentar a qualidade e a produtividade no desenvolvimento de software. Um fato amplamente reconhecido é que a qualidade do produto de software pode ser, em grande parte, determinada pela qualidade do processo utilizado para desenvolvê-lo e mantê-lo. A avaliação do processo de software ajuda as organizações de software a amadurecerem seus processos, identificando problemas críticos para estabelecer prioridades de melhoria. Essa avaliação pode ser feita por meio da comparação do estado dos processos da organização em relação a um modelo de referência que estabeleça estágios de melhoria. Uma avaliação geralmente se baseia em um modelo de processo de software que fornece um roteiro para melhorias. Este trabalho tem como objetivo estabelecer uma abordagem que: (i) define um conjunto de modelos de abstração (metamodelos) de modelos de maturidade de processo de software para apoiar uma metodologia de avaliação/melhoria de processo de software com o objetivo de certificação; e (ii) permite avaliar os processos de uma organização em comparação com um modelo de maturidade por meio de transformações desses metamodelos. A abordagem é instanciada por meio de um estudo de caso utilizando os modelos MPS.Br e CMMI para exemplificar sua aplicação. Como resultado, é apresentado um comparativo entre as limitações encontradas nas metodologias encontradas na literatura e como a abordagem sugere superá-las. / Software process improvement (SPI) is a software engineering practice motivated by the need to increase the quality and productivity in software development. A fact widely recognized is that the quality of the software product can be largely determined by the quality of the process used to develop and maintain it. The assessment of software process helps software organizations to improve themselves, identifying their critical problems to establish priorities for improvement. This assessment can take place by comparing the state of the organization on their software processes to a reference model that shows stages of improvement in scales. An assessment is usually based on a software process model that provides a roadmap for improvement. This work aims to establish an approach that: (i) defines a set of abstraction models (metamodels) of software process maturity models to support an assessment/improvement methodology aiming software process certification; and (ii) evaluates the organization processes in comparison with the maturity models through transformations of those metamodels. The approach is instantiated through a case study using the MPS.Br and CMMI models to illustrate its application. As a result, a comparison between the limitations found in the methodologies identified in the literature and how the approach suggested overcome them is presented.