Este trabalho de mestrado apresenta a modelagem, a prototipação e os resultados do desenvolvimento de um middleware para composição dinâmica de Web Services denominado DWSC-M (Dynamic Web service Composition Middleware). O objetivo principal desse middleware é permitir que serviços sejam compostos dinamicamente considerando aspectos de qualidade de serviço na escolha dos serviços que fazem parte de um fluxo de composição. Para complementar o funcionamento do middleware DWSC-M foram propostos dois algoritmos para seleção de Web Services: o primeiro utiliza seleção aleatória e o segundo utiliza distância Euclidiana para seleção de serviços e considera, para tal finalidade, os parâmetros de QoS enviados pela requisição do cliente do serviço / This work presents the modeling, the prototype and the results of the developing of a middleware for dynamic composition of Web Services named DWSC-M (Dynamic Web Service Composition Middleware). The main focus of this middleware is to allow services being dynamically composed, considering aspects of quality of service in the choice of services that are part of the composite flow. Complementing the operation of the DWSC-M middleware two algorithms were proposed for Web Services selection : the first one uses Random selection and the second one uses Euclidean Distance for the selection of services and considers for this purpose the QoS parameters sent by the client service request

Neste projeto é proposta uma avaliação e comparação de diretrizes e a adequação de técnicas que permitam não somente a criação de Web services seguros, mas também a validação dos serviços utilizados para determinar se a aplicação possui as características almejadas relacionadas ao desempenho e à segurança. Neste sentido, é primordial analisar as principais especificações de segurança empregadas em Web services no contexto atual, bem como avaliar os algoritmos criptográficos e o comprimento das chaves utilizadas. Os resultados obtidos permitem determinar, com base nos objetivos especificados, qual o impacto dos mecanismos de segurança utilizados no desempenho da aplicação / In this project we propose an evaluation and comparison of guidelines and appropriateness of techniques that allow not only the creation of secure Web services, but also the validation of the services used to determine whether the application has the desired characteristics related to performance and security. In this sense it is crucial to analyze the main security specifications used in Web services in the current context, as well as evaluating the cryptographic algorithms and key length used. The results obtained allow to determine, based on specified objectives, the impact of security mechanisms used in application performance

A popularização dos dispositivos móveis em todas as camadas sociais tem motivado o desenvolvimento de aplicações educacionais móveis, denominadas aplicações de m-learning. Neste cenário, as aplicações existentes, mesmo possuindo diversos benefícios e facilidades no que diz respeito ao ensino e aprendizagem, apresentam problemas e desafios relacionados, sobretudo no que se refere ao desenvolvimento, reuso e padronização arquitetural. Por outro lado, na vertente do reúso de software, percebe-se uma crescente adoção do conceito de Linha de Produtos de Software (LPS). Esse paradigma possibilita às organizações explorar as similaridades e variabilidades de seus produtos, aumentando a reutilização de artefatos e, como consequência, diminuindo custos e tempo de desenvolvimento. Neste trabalho é apresentada uma LPS voltada ao domínio das aplicações de m-learning, denominada M-SPLearning. A proposição da M-SPLearning envolveu desde o estudo inicial para a obtenção de uma análise de domínio efetiva, até a implementação dos componentes previamente analisados. A LPS concebida teve seus respectivos produtos avaliados experimentalmente no cenário industrial, fornecendo evidências de que sua utilização pode acelerar o time-to-market de produtos de m-learning, com um número reduzido de defeitos. / The popularity of mobile devices in all social classes has motivated the development of mobile educational applications, called m-learning applications. The existing applications, even having many benefits and facilities in relation to teaching and learning, also have problems and challenges, especially regarding the development, reuse and architectural standardization. Particularly, there is an increasing adoption of the concept of Software Product Line (SPL) in researches related to reuse. This paradigm enables organizations to explore the similarities and variabilities of their products, increasing the reuse of artifacts and, consequently, reducing costs and development time. This work presents an SPL focused on the domain of m-learning applications, named M-SPLearning. The development of M-SPLearning has comprised since the initial study for an effective domain analysis until the implementation of the components previously analyzed. Such SPL had its products experimentally evaluated in the industrial scenario, providing evidences that its use can accelerate the time-to-market of m-learning applications, with a reduced number of faults.

Composição de serviços é um tópico que tem atraído cada vez mais o interesse por parte de pesquisadores na área de sistemas distribuídos. Além disso, o interesse por ambientes baseados em nuvem tem crescido significativamente conforme o seu uso aumenta e se firma como um importante modelo de negócios. Coreografias são formas de composições de serviços em que não há pontos centrais de falha; a responsabilidade da sua execução é distribuída entre os vários serviços componentes. Devido à natureza distribuída do fluxo de informações e dados de controle, o cumprimento de \\textit{Service Level Agreements} (SLAs) depende estritamente do monitoramento da Qualidade de Serviços (QoS), recursos virtuais da nuvem e mecanismos de reconfiguração dinâmica, capazes de automaticamente adaptar composições a mudanças de estado no sistema. Nesta dissertação, abordamos o estudo do gerenciamento de QoS em coreografias de serviços. Para isso desenvolvemos um sistema de middleware capaz de implantar e gerenciar o QoS de composições. Este teve seu desempenho avaliado utilizando o serviço Amazon EC2. Os resultados da avaliação mostram que com pouco esforço por parte dos desenvolvedores de composições, é possível cumprir o SLA de composições dentro do esperado utilizando escalabilidade horizontal ou vertical provida pelo middleware automaticamente. Adicionalmente, a nossa proposta traz economias em relação ao custo de implantação pois diminui a quantidade de recursos subutilizados. / Service composition has been a hot topic that has attracted the interesting of researchers in the distributed system area. Moreover, the interesting in cloud computing based environment has grown significantly. Its use has grown and it became to be a important business model. Choreographies are an specific kind of service composition that has no single point of failure; the responsibility of execution is distributed among the services. Due to the distributed nature of the these systems, the fulfilment of Service Level Agreements (SLAs) depends strictly on and automatic way to monitoring Quality of Service (QoS) and virtual computional resources as well as dinamic reconfiguration mechanisms, to be capable of automatically adapting compositions to changing environment. In this work, we studied QoS management in service choreographies. In order, we devised a middleware system capable of deploy service compositions and manage QoS of them. The middleware was evaluated using the Amazon EC2 cloud provider. The results shows that with less effort from the composition providers, it is possible to fulfil SLAs using horizontal or vertical scalability provided by the middleware automatically. Additionaly, our proposal brings up a cost reduction of deploy by decreasing the amount of underused resources.

L’omniprésence des systèmes logiciels et le rôle important qu’ils jouent dans la vie quotidienne rendent les utilisateurs de plus en plus exigeants. Entre autre, ils demandent plus de fiabilité et des systèmes qui peuvent s’adapter à leur contexte d’utilisation. Afin de satisfaire ces demandes, les cadres techniques et les méthodes de conception sous-jacents au développement des systèmes doivent être modulaires, flexibles et consistants. L’architecture orientée service (SOA) est un paradigme qui offre des mécanismes permettant une grande flexibilité des architectures des systèmes logiciels tout en réduisant leurs coûts de développement puisqu’elle se base sur des entités modulaires et réutilisables appelées services. Ces services peuvent être réutilisés dans le cadre d’une composition ou d’une chorégraphie de services pour la construction de nouveaux processus métiers transverses. SOA promet aussi d’augmenter la fiabilité des systèmes au travers de la notion de contrat de services. De son côté, le paradigme de l’Ingénierie des modèles (IDM) offre au travers de ses deux principes fondateurs, l’abstraction et l’automatisation, deux moyens puissants de gestion de la complexité des systèmes. Malgré les progrès des deux paradigmes, IDM et SOA, il y a encore des défis à résoudre. Notamment, on peut citer : (1) La vérification rigoureuse des spécifications des systèmes conformes aux principes de SOA. Ce point constitue un défi car pour modéliser ces systèmes, les concepteurs ont besoin de plus d'un point de vue représentant chacun une préoccupation spécifique du système et bien sûr ces points de vue doivent être sémantiquement cohérents. Ce problème est appelé la vérification de la consistance horizontale, une tâche manuellement difficile qui constitue une étape importante pour réduire les incohérences dans les modèles des applications SOA avant de les transformer en d'autres formes (du code, des cas de tests, etc.). (2) La transformation des spécifications des systèmes en artefacts exécutables. Malgré la maturité de l’architecture SOA, la transformation des spécifications des systèmes SOA en artefacts exécutables s'avère encore une étape fastidieuse et est généralement effectué manuellement. En particulier, la transformation des chorégraphies de services en orchestrations exécutables reste un problème en raison de la nécessité de prendre en compte les aspects complexes des systèmes distribués, tels que l’asynchronisme et la concurrence. (3) La vérification de l’exécution. Au moment de la spécification, des comportements inattendus peuvent encore apparaitre lors de l’exécution. Pour cette raison, il est nécessaire de pouvoir vérifier la conformité de l'exécution d’un système par rapport à sa spécification. Ce problème est appelé la vérification de la consistance verticale. Ce travail de thèse propose ainsi une approche de type SOA dirigée par les modèles résolvant les défis mentionnés précédemment. Cette approche comprend une méthodologie en deux étapes pour la vérification de la consistance horizontale et verticale des systèmes SOA spécifiés en utilisant la norme SoaML de l’OMG. Le problème de vérification de la consistance horizontale est résolu au moyen de l'analyse statique de la spécification des systèmes. Le deuxième défi est résolu en spécifiant les règles de transformation d'un modèle de spécification de chorégraphie de services en une orchestration exécutable qui implémente la logique de la chorégraphie tout en prenant en compte la nature asynchrone des communications entre les services distribués. Le problème de vérification de la consistance verticale est résolu par notre approche par l'analyse hors ligne des traces d’exécution d’un système. L’ensemble de la proposition méthodologique a été implanté sous la forme d’une extension à l’outil de modélisation UML open-source Papyrus. / As software systems are pervasive and play an important role in everyday life, the users are becoming more and more demanding. They mainly require more reliable systems that automatically adapt to different use cases. To satisfy these requirements, technical frameworks and design methods, upon which the systems development is based, must meet specific objectives mainly modularity, flexibility, and consistency. Service-Oriented Architecture (SOA) is a paradigm that offers mechanisms to increase the software flexibility and reduce development costs by enabling service orchestration and choreography. SOA promises also reliability through the use of services contracts as an agreement between the service provider and consumer. Model-driven SOA is a novel and promising approach that strengthens SOA with Model-Driven Engineering (MDE) technics that ease the specification, development, and verification of Service-Oriented Applications by applying abstraction and automation principles. Despite the progress to integrate MDE to SOA, there are still some challenging problems to be solved: (1) Rigorous verification of SOA system specifications. This is a challenging problem because to model SOA systems designers need more than one viewpoint, each of which captures a specific concern of the system. These viewpoints are meant to be semantically consistent with each other. This problem is called horizontal consistency checking and it is an important step to reduce inconsistencies in SOA models before transforming them into other forms (code generation, test cases derivation, etc.). (2) Transformation of systems specifications into executable artifacts. Despite the maturity of SOA, the transformation of system specifications into executable artifacts is usually manual, fastidious and error-prone. The transformation of services choreographies into executable orchestrations particularly remains a problem because of the necessity to take into account critical aspects of distributed systems such as asynchrony and concurrency when executing centralized orchestrations. (3) Runtime verification. Even after verifying Horizontal consistency at design time, there could be unexpected and unspecified data interactions that are unknown during design-time. For this reason, we still need consistency verification at runtime to handle such unforeseen events. This problem is called Vertical consistency checking. This thesis work proposes a Model-driven SOA approach to address the above-mentioned challenges. This approach includes a two-step model-driven methodology to horizontally and vertically verify the consistency of SOA systems specifications described using the SoaML standard from the Object Management Group (OMG). The horizontal consistency checking problem, which is the first challenge, is solved by means of static analysis of the system specification at the design level. The second challenge is solved by specifying the transformation from a choreography specification model to an executable orchestration implementing the choreography logic. Our transformation takes into consideration the asynchronous nature of the communications between distributed services. The vertical consistency checking problem, which is the third challenge, is solved by our approach thanks to offline analysis that allows consistency verification between both design and runtime levels. The entire methodological proposal was implemented as an extension to the open source UML modeling tool Papyrus.

Im Rahmen dieser Dissertation wird sich mit der Einbettung komplexer Datenanalyseprozesse in serviceorientierten Umgebungen beschäftigt. Diese Betrachtung beginnt mit einem konkreten Anwendungsgebiet, indem derartige Analyseprozesse eine entscheidende Rolle bei der Wissenserschließung spielen und ohne deren Hilfe kein Fortschritt erzielt werden kann. Im zweiten Teil werden konkrete komplexe Datenanalyseprozesse entwickelt, die den Ausgangspunkt für die Erörterung der Einbettung in eine serviceorientierte Umgebung bilden. Auf diese Einbettung wird schlussendlich im dritten Teil der Dissertation eingegangen und entsprechende Erweiterungen an den Technologien der bekanntesten Realisierungsform präsentiert. In der Evaluierung wird gezeigt, dass diese neue Form wesentlich besser geeignet ist für komplexe Datenanalyseprozesse als die bisherige Variante.

This PhD thesis aims to improve the knowledge on the processes and chemical species in the gas- and particle-phases that are involved in the production of secondary organic aerosol (SOA) from monoterpene oxidation in the atmosphere. A denuder/filter technique that enabled the simultaneous sampling of gaseous and particulate compounds was applied in the present study. The sampling technique was comprehensively characterised and optimised using twelve atmospherically relevant carbonyl compounds. The present study improved the denuder coating procedure and the sampling performance. An additional coating with the derivatisation reagent, 2,4‑dinitrophenylhydrazine (DNPH), reduced the break-through potential (e.g., from 98% to 0.9% for methyl vinyl ketone) and the fraction of carbonyl compounds on the filter material (e.g., from 8.7% to 0% for acetone). Calibration experiments against an aerosol chamber were performed to reduce the relative standard deviation (RSD) of the calibration points in the denuder measurements. The RSDs were reduced by half for acetone, acetaldehyde, methyl vinyl ketone, glyoxal, benzaldehyde and campholenic aldehyde using a XAD‑4/DNPH denuder, and the quantification error was also reduced. This sampling technique was then applied to a series of α- and β-pinene ozonolysis experiments. The present study examined the influence of an OH radical scavenger (CO), and hence the HO2/RO2 ratio, on the SOA formation, product distribution and partitioning behaviour of selected oxidation products in conjunction with different seed particle acidities. It was shown that SOA yields increased by about 8% in α-pinene ozonolysis when CO and acidic seed particles co-existed, whereas only a marginal difference was observed (increase of 2%) for β-pinene compared to neutral seed particles. From the denuder/filter sample analysis, it was possible to tentatively identify a new compound from the α-pinene ozonolysis, i.e., terpenylic aldehyde. Gas- and particle-phase yields were estimated for the first time for this compound (i.e., 1% and 0.4%, respectively). The atmospheric relevance of terpenylic aldehyde was demonstrated based on ambient filter measurements and a possible formation pathway was suggested. Furthermore, the present study provided an additional explanation for enhanced SOA formation when acidic seed particles are used in monoterpene ozonolysis. It was demonstrated that the isomerisation of monoterpene oxides on acidic seed particles leads to the formation of highly reactive SOA precursors, whose subsequent reaction with ozone contributes significantly to SOA formation.

<p style="text-align: justify;">U okviru doktorske disertacije predstavljen je profil modela domena za katastar<br />nepokretnosti u Srbiji, kao i model servisa kojim se opisuju procesi u katastru<br />neophodni za uspe&scaron;no i efikasno izvr&scaron;avanje poslova. U tu svrhu izvr&scaron;en je pregled<br />stanja postojećeg informacionog sistema katastra nepokretnosti u Srbiji, izvr&scaron;ena je<br />analiza postojećih problema i koraka koje je neophodno sprovesti kako bi se izvr&scaron;ilo<br />unapređenje i povećala efikasnost poslovanja. Prikazana je studija primenljivosti ISO<br />19152 standarda na katastar nepokretnosti u Srbiji. Rezultat je profil modela domena<br />za katastar nepokretnosti kojim se obezbeđuje interoperabilnost sistema. Takođe su<br />predstavljeni poslovni procesi u katastru i definisana je njihova hijerarhijska<br />organizacija. Na osnovu dobijenih procesa predložen je model servisa za katastar<br />nepokretnosti u Srbiji. Model servisa obuhvata servise poslovanja katastra<br />nepokretnosti, uslužne servise prema različitim korisnicima i geoprostorne servise.<br />Potom je izvr&scaron;ena verifikacija modela servisa kroz studiju slučaja upotrebe definisanih<br />servisa.</p>

La réutilisation des services pour prendre en charge de nouveaux processus métier, en plus de l'alignement de l'informatique sur les fonctions métier, constitue une motivation clé pour l'utilisation de l'architecture orientée services (SOA) pour le développement de solutions métier. Dans une architecture orientée services, il est important de faciliter la sélection, la configuration et la composition des services existants pour faire face aux changements d’exécution ou à l’évolution des besoins des utilisateurs finaux. Contrairement aux autres systèmes logiciels traditionnels, le comportement dynamique des systèmes basés sur les services nécessite des informations de qualité de service (QoS) actualisées pour assurer une gestion appropriée dans les différentes étapes du cycle de vie. Les entreprises doivent connaître les performances des services Web et des processus métier pour préserver leur pérennité en matière de réutilisation des services. Les trois principaux avantages de la réutilisation des services sont l'amélioration de l'agilité des solutions en assemblant rapidement de nouveaux processus métier à partir des services existants pour répondre aux besoins changeants du marché, réduire les coûts en ne développant pas de nouveaux services pour activer des fonctions métier similaires dans plusieurs processus métier, mais également le déploiement et la gestion des services dans les environnements d'exécution tout au long du cycle de vie SOA. Cependant, il existe actuellement de nombreux défis liés à la durabilité et à la gouvernance du comportement des services pendant son cycle de vie. Parmi ces défis, on peut citer le niveau de performance, la persistance des exigences et l'adaptabilité du service. De plus, il existe certaines limites des outils de surveillance. Ils manquent d’anticipation dans la détection des problèmes et ils sont passifs et ne sont ni réactifs ni prédictifs. Cette thèse porte sur l’évaluation et les recommandations en matière de performance et de gouvernance des systèmes d’information pour suggérer la réutilisation des services au cours de son évolution. L'objectif est de maintenir la durabilité, la robustesse, l'adaptabilité, la réutilisabilité et l'évolutivité des systèmes d'information. À cette fin, nous évaluons les performances de l'architecture orientée service. Il existe plusieurs solutions de surveillance existantes conçues pour prendre en charge une couche spécifique de SOA. En particulier, BAM est un outil de surveillance des activités commerciales permettant de surveiller le flux de données pour les processus métier. Cependant, la surveillance BAM ne fournit pas l'évaluation des performances pour recommander des services et des processus à réutiliser. Il existe très peu d'approches prenant en charge la surveillance des couches SOA. De plus, les solutions sont partiellement dynamiques avec une aide à la décision limitée. Par conséquent, nous proposons une aide à la décision basée sur la performance pour une architecture orientée services. Il se compose de quatre couches en tant que couches de spécification, de gestion des données, d'exploration de données et de décision. La couche de spécification identifie les exigences de l'utilisateur final et les traite via l'ontologie proposée. La couche de données analyse les indicateurs techniques conformes aux normes de qualité les plus récentes, ISO 25010. Les caractéristiques de qualité sont liées à l'efficacité des performances, à la fiabilité et à la réutilisation. La couche d'exploration de données génère des décisions spécifiques basées sur des instances de service en appliquant les algorithmes d'apprentissage automatique. Il utilise les concepts ontologiques proposés et les règles d'inférence sémantique du service, des processus métier, des couches serveur et d'intégration. La couche d'exploration de données renvoie aux ontologies avec ces décisions spécifiques où des règles plus raffinées ont été générées.... / Reuse of services in supporting new business processes, in addition to alignment of IT with business functions, is a key motivation in using Service-Oriented Architecture (SOA) for developing business solutions. In a service-oriented architecture, it is important to smooth the selection, configuration and composition of existing services to deal with the runtime changes or the evolution of End User requirements. In contrast to other traditional software systems, the dynamic behavior of service based systems requires up-to-date quality of service (QoS) information for its proper management in the different stages of the lifecycle. Organizations need to know the performance of Web services and business processes to maintain their sustainability for reuse of services. The three key benefits of service reuse are improving agility of solutions by quickly assembling new business processes from existing services to meet changing marketplace needs, reducing cost by not developing new services for enabling similar business functions across multiple business processes, but also spanning service deployment and management in runtime environments throughout the SOA lifecycle. However currently, there are many challenges related to the sustainability and governance of service behavior during its lifecycle. Among those challenges, one can mention level of performance, persistence of the requirements and adaptability of the service. Moreover, there are some limitations of monitoring tools. They lack of anticipation in problem detection, and they are passive and neither reactive nor predictive. This thesis focuses on providing assessment and recommendations for performance and governance of information systems for suggesting service reuse during its evolution. The aim is to maintain sustainability, robustness, adaptability, reusability and evolvability of information systems For this purpose, we evaluate the performance of service oriented architecture. There are several existing monitoring solutions designed to support a specific layer of SOA. Particularly, BAM is a business activity monitoring tool for monitoring the flow of data for business processes. However, BAM monitoring do not provide the performance evaluation for recommending services and processes to reuse. There are very few approaches that support monitoring of SOA layers together. Furthermore, the solutions are partially dynamic with limited decision support. Therefore, we propose performance based decision support for service oriented architecture. It consists of four layers as specification, data management, data mining and decision layers. The specification layer identifies the requirements from the End User and process through the proposed ontology. The data layer analyzes technical indicators that are compliant to the latest quality standard, ISO 25010. Quality characteristics are related to performance efficiency, reliability and reusability. The data mining layer generates specific decisions based on service instances by applying the machine learning algorithms. It uses the proposed ontological concepts and semantic inference rules of service, business process, server and integration layers. The data mining layer returns back to ontologies with these specific decisions where more refined rules have been generated from new ontological concepts. The decision layer processes these results and generates a global decision in terms of recommendations. It provides multi-viewpoints decision to reuse existing services or suggesting their composition. To motivate the proposition of this approach, we illustrate the implementation of the proposed algorithms for all the four layers by a business process use case and data set of public repository of shared services. The output of our system is recommendation for reuse of atomic service, composite service and resource allocation provisioning. We ensure the sustainability, adaptability...

O planejamento de experimentos em sistemas computacionais não é uma tarefa trivial, pois envolve diversas etapas tais como, o planejamento propriamente dito, a execução dos experimentos e a análise dos resultados. A definição e a utilização de metodologias adequadas para cada uma destas etapas facilita a obtenção dos resultados de um experimento em um sistema computacional. Neste trabalho são apresentados mecanismos para auxiliar o planejamento e execução de experimentos em sistemas orientados a serviços. O planejamento de experimento é realizado a partir de um modelo baseado nos conjuntos de entradas comuns a arquiteturas orientadas a serviço. A execução deste planejamento é feita em um ambiente colaborativo real, a qual auxilia a identificação de gargalos que não estão presentes em simulações ou modelos analíticos. Um estudo de caso aplicado na arquitetura WSARCH, possibilitou avaliar seu desempenho e identificar problemas de configuração / The design of experiments in computational systems is not a trivial task as it involves several steps such as planning and execution of the experiments and the analyse of the results. The use of appropriate methodologies for each of these steps makes it easier obtain the experiment results of a computer system. In this dissertation, mechanisms to assist the planning and execution of experiments in service-oriented systems are presented. The planning of the experiment is made according to a model based on a set of common entries for service-oriented architectures. The experiment execution is performed in a real collaborative environment, which helps to identify bottlenecks that are not found in simulations or analytical models. A study case applied in WSARCH architecture, enables to evaluate the performance and identify configuration problems