As control systems become more integrated with high-end engineering systems as well as consumer products, they are expected to achieve specifications that may include logic rules, safety constraints, startup procedures, and so forth. Control design for such complex specifications is a relatively unexplored research area. One possible design approach is based on partitioning the state space into polytopic regions, and then formulating a certain control problem on each polytope, with the intention that the set of all controllers so obtained would collectively achieve the specification. The control problem which must be solved for each polytope is called the reach control problem, and it has been identified as turnkey to the further development of this approach. The reach control problem (RCP) is to find a state feedback to make the closed-loop trajectories of an affine (or linear) control system defined on a polytope reach and exit a prescribed facet of the polytope in finite time. This dissertation studies a number of aspects of the reach control problem, and it uses tools from convex analysis, nonsmooth analysis, and computational geometry for this study. The dissertation has three main themes. First, we formulate and solve a variant of RCP in which trajectories exit the polytope in a monotonic sense; this provides a triangulation-independent solution of RCP. Second, we develop a Lyapunov-like theory for verifying if RCP is solved using a given candidate controller. This involves the introduction of the notion of generalized flow functions, a LaSalle Principle for RCP, and several converse theorems on existence of generalized flow functions. Third, we study the relationship between affine feedbacks and continuous state feedbacks for RCP on simplices. Although the two feedback classes have been shown to be equivalent under an assumption on the triangulation of the state space, we show by a counterexample that the equivalence is no longer true under arbitrary triangulations. Then we provide for single-input systems a constructive method for the synthesis of multi-affine feedbacks for RCP on simplices.

As control systems become more integrated with high-end engineering systems as well as consumer products, they are expected to achieve specifications that may include logic rules, safety constraints, startup procedures, and so forth. Control design for such complex specifications is a relatively unexplored research area. One possible design approach is based on partitioning the state space into polytopic regions, and then formulating a certain control problem on each polytope, with the intention that the set of all controllers so obtained would collectively achieve the specification. The control problem which must be solved for each polytope is called the reach control problem, and it has been identified as turnkey to the further development of this approach. The reach control problem (RCP) is to find a state feedback to make the closed-loop trajectories of an affine (or linear) control system defined on a polytope reach and exit a prescribed facet of the polytope in finite time. This dissertation studies a number of aspects of the reach control problem, and it uses tools from convex analysis, nonsmooth analysis, and computational geometry for this study. The dissertation has three main themes. First, we formulate and solve a variant of RCP in which trajectories exit the polytope in a monotonic sense; this provides a triangulation-independent solution of RCP. Second, we develop a Lyapunov-like theory for verifying if RCP is solved using a given candidate controller. This involves the introduction of the notion of generalized flow functions, a LaSalle Principle for RCP, and several converse theorems on existence of generalized flow functions. Third, we study the relationship between affine feedbacks and continuous state feedbacks for RCP on simplices. Although the two feedback classes have been shown to be equivalent under an assumption on the triangulation of the state space, we show by a counterexample that the equivalence is no longer true under arbitrary triangulations. Then we provide for single-input systems a constructive method for the synthesis of multi-affine feedbacks for RCP on simplices.

Among the plethora of solutions to the Business-to-Business interoperability problem, no other solution has obtained as much attention asWeb Services Technology (WST), which allows entities to exchange data regardless of their underlying platforms. WST also allows services to be composed in order to provide high quality customer service over the web. In order to perform transactions across different service providers, standard protocols need to be supported by participating providers. Many useful protocols are coming into the market, but are often ambiguously specified by protocol designers and not fully verified. Furthermore, even if the specifications are reasonably clear, programmers often make subtle assumptions, possibly leading to errors that are hard to detect and locate, especially when the number of participating entities is dynamic. Consequently, these can lead to interoperability problems among implementations of the same protocol and high software maintenance costs. To address these issues, a hierarchical automata-based framework is proposed to model the functional aspects of Web Services (WS) protocols that also assists in verifying their correctness. The modelling formalism has a sound mathematical foundation and aims to reconcile desirable features while still maintaining syntactic and semantic simplicity. The properties to be verified are specified using a pattern system and/or 'observer' states, which have been adapted for WS protocols. In particular, always in a positive observer state implies proper termination and partial functional correctness while reachability of a negative observer state signifies deadlock and/or violation of a safety property. Verification itself is handled by automatic translation of the model and its properties into a model-checker's input code and interpretation of the output produced by the model-checker. A test-bed is proposed to check the conformance of a protocol implementation to its specification It helps in locating errors in the implementations of WS protocols especially where the number of participating entities is dynamic. Conformance checking is achieved by capturing sequences of exchanged messages of the actual implementations and checking them against the formal specification. Experience using the framework is also described and illustrated using two non-trivial WS protocols, namely WS-BusinessActivity and WS-AtomicTransaction.

No description available.

O uso de serviços em nuvem tem o potencial de oferecer vários benefícios para pequenas e médias empresas, como disponibilidade de recursos sob demanda, pagamento conforme o uso e escalabilidade. Apesar de existirem vários estudos e ferramentas para apoiar a migração de aplicações para serviços em nuvem, existe uma carência de diretrizes para apoiar a migração para a nuvem de forma sistemática. Como consequência, a migração é feita de forma ad hoc, o que pode aumentar significativamente os custos e comprometer o sucesso da migração. Essa pesquisa usa a KAOS, uma técnica da engenharia de requisitos orientada a metas, para criar um catálogo de metas que orienta equipes na migração de aplicações para cinco serviços de nuvem amplamente utilizados: banco de dados relacional, máquinas virtuais, armazenamento, deployment e filas. Metas, que representam objetivos de migração, foram extraídas seguindo um processo que utiliza os modelos de metas, de responsabilidade e de obstáculos que pertencem ao KAOS. Uma avaliação com profissionais experientes em migração indicou que o catálogo de metas pode ajudar empresas e profissionais com pouca experiência na migração de aplicações para serviços em nuvem além de contribuir na identificação de aspectos críticos e relevantes do processo de migração. Pequenas e médias empresas podem economizar um esforço significante usando o catálogo de metas como guia durante o processo de análise de transferência de aplicações para serviços em nuvem. / Cloud services might offer several benefits to small and medium companies, such as on-demand resource provisioning, pay-as-you-go, and scalability. Although there are several studies and tools to support the application migration to the cloud, the lack of guidelines to support a systematic cloud migration often leads to ad hoc migrations, which significantly increase costs and compromise the migration success. This research uses the KAOS, a goal-oriented requirement engineering technique, to devise a catalogue of goals that guide migration teams when migratingWeb applications to five widely used cloud services: relational databases, virtual machines, storage, deployment and queuing. Goals, which represent migration objectives, were identified following a systematic process based on the KAOS goal, responsibility and obstacle model. A rigorous evaluation with qualified professionals showed that the catalogue assists novice companies and professionals regarding cloud migration. In addition, the catalogue contributes to identifying critical and relevant aspects of the migration process. Small and medium companies might save a significant effort by using the catalogue as a guide when analysing the migration of applications to the cloud.

A Engenharia de Software é um processo participativo que envolve todos os interessados ativamente no projeto. Dentro de um domínio complexo, como a área do direito, os usuários e especialistas do domínio possuem um papel importante no processo de elicitação de requisitos, em especial na composição de requisitos de evolução de software para sistemas existentes, considerando que a especificação dos requisitos deve ser realizada de forma específica ao domínio. Contudo, as ambiguidades são um fenômeno cotidiano na área jurídica, devido à própria natureza deste domínio, e ainda o uso predominante da linguagem natural. Tais ambiguidades são refletidas nos requisitos de evolução dos sistemas de software usados no direito, por seus usuários e também por especialistas do domínio, ocasionando problemas de compreensão para os analistas de sistema. Os mapas conceituais apresentam-se como uma ferramenta cognitiva, sendo apta para o uso em processos de comunicação. O presente trabalho aplica os mapas conceituais no nível de comunicação entre usuários e especialistas do domínio jurídico e os analistas de sistema, visando a redução de ambiguidades nos requisitos de evolução de software na área jurídica. Um modelo foi formalizado e testado via experimentação, com a aplicação de um protótipo funcional junto a estudantes de graduação e profissionais do direito. Os resultados apontam uma redução das ambiguidades do tipo falta de clareza, apresentando que a metodologia proposta proporciona melhor interpretação dos requisitos de evolução de software do domínio jurídico para os analistas de sistema e facilita a produção de requisitos pelos usuários. / Software Engineering is a participatory process that involves all stakeholders actively in design. On a complex domain, such as juridical area, users and domain experts have an important role in requirements elicitation process, especially in composition of evolution requirements for existing systems, whereas that requirements specification must specific to domain. However, ambiguities are everyday event in juridical area, reason associated own nature of domain and predominant use of natural language. Such ambiguities are reflected in the evolution requirements of juridical software systems, users and domain experts, causing problems of understanding for systems analysts. The conceptual maps are introduce as cognitive tool, being appropriate for use in communication processes. This work applies conceptual maps in the level of communication between users and juridical experts to system analysts, with the goal to reduce ambiguities in evolution requirements of juridical systems. A model was designed and tested by experimentation, with application of a functional prototype to undergraduate students and law professionals. The results points the ambiguities reduction of unclarity category, showing that proposed methodology provides better interpretation of the software evolution requirements of the juridical domain systems for systems analysts and easy making user requirements.

O uso de serviços em nuvem tem o potencial de oferecer vários benefícios para pequenas e médias empresas, como disponibilidade de recursos sob demanda, pagamento conforme o uso e escalabilidade. Apesar de existirem vários estudos e ferramentas para apoiar a migração de aplicações para serviços em nuvem, existe uma carência de diretrizes para apoiar a migração para a nuvem de forma sistemática. Como consequência, a migração é feita de forma ad hoc, o que pode aumentar significativamente os custos e comprometer o sucesso da migração. Essa pesquisa usa a KAOS, uma técnica da engenharia de requisitos orientada a metas, para criar um catálogo de metas que orienta equipes na migração de aplicações para cinco serviços de nuvem amplamente utilizados: banco de dados relacional, máquinas virtuais, armazenamento, deployment e filas. Metas, que representam objetivos de migração, foram extraídas seguindo um processo que utiliza os modelos de metas, de responsabilidade e de obstáculos que pertencem ao KAOS. Uma avaliação com profissionais experientes em migração indicou que o catálogo de metas pode ajudar empresas e profissionais com pouca experiência na migração de aplicações para serviços em nuvem além de contribuir na identificação de aspectos críticos e relevantes do processo de migração. Pequenas e médias empresas podem economizar um esforço significante usando o catálogo de metas como guia durante o processo de análise de transferência de aplicações para serviços em nuvem. / Cloud services might offer several benefits to small and medium companies, such as on-demand resource provisioning, pay-as-you-go, and scalability. Although there are several studies and tools to support the application migration to the cloud, the lack of guidelines to support a systematic cloud migration often leads to ad hoc migrations, which significantly increase costs and compromise the migration success. This research uses the KAOS, a goal-oriented requirement engineering technique, to devise a catalogue of goals that guide migration teams when migratingWeb applications to five widely used cloud services: relational databases, virtual machines, storage, deployment and queuing. Goals, which represent migration objectives, were identified following a systematic process based on the KAOS goal, responsibility and obstacle model. A rigorous evaluation with qualified professionals showed that the catalogue assists novice companies and professionals regarding cloud migration. In addition, the catalogue contributes to identifying critical and relevant aspects of the migration process. Small and medium companies might save a significant effort by using the catalogue as a guide when analysing the migration of applications to the cloud.

A Engenharia de Software é um processo participativo que envolve todos os interessados ativamente no projeto. Dentro de um domínio complexo, como a área do direito, os usuários e especialistas do domínio possuem um papel importante no processo de elicitação de requisitos, em especial na composição de requisitos de evolução de software para sistemas existentes, considerando que a especificação dos requisitos deve ser realizada de forma específica ao domínio. Contudo, as ambiguidades são um fenômeno cotidiano na área jurídica, devido à própria natureza deste domínio, e ainda o uso predominante da linguagem natural. Tais ambiguidades são refletidas nos requisitos de evolução dos sistemas de software usados no direito, por seus usuários e também por especialistas do domínio, ocasionando problemas de compreensão para os analistas de sistema. Os mapas conceituais apresentam-se como uma ferramenta cognitiva, sendo apta para o uso em processos de comunicação. O presente trabalho aplica os mapas conceituais no nível de comunicação entre usuários e especialistas do domínio jurídico e os analistas de sistema, visando a redução de ambiguidades nos requisitos de evolução de software na área jurídica. Um modelo foi formalizado e testado via experimentação, com a aplicação de um protótipo funcional junto a estudantes de graduação e profissionais do direito. Os resultados apontam uma redução das ambiguidades do tipo falta de clareza, apresentando que a metodologia proposta proporciona melhor interpretação dos requisitos de evolução de software do domínio jurídico para os analistas de sistema e facilita a produção de requisitos pelos usuários. / Software Engineering is a participatory process that involves all stakeholders actively in design. On a complex domain, such as juridical area, users and domain experts have an important role in requirements elicitation process, especially in composition of evolution requirements for existing systems, whereas that requirements specification must specific to domain. However, ambiguities are everyday event in juridical area, reason associated own nature of domain and predominant use of natural language. Such ambiguities are reflected in the evolution requirements of juridical software systems, users and domain experts, causing problems of understanding for systems analysts. The conceptual maps are introduce as cognitive tool, being appropriate for use in communication processes. This work applies conceptual maps in the level of communication between users and juridical experts to system analysts, with the goal to reduce ambiguities in evolution requirements of juridical systems. A model was designed and tested by experimentation, with application of a functional prototype to undergraduate students and law professionals. The results points the ambiguities reduction of unclarity category, showing that proposed methodology provides better interpretation of the software evolution requirements of the juridical domain systems for systems analysts and easy making user requirements.

Este trabalho discute o projeto de compensadores multivariáveis robustos com especificações no domínio do tempo. Primeiramente faz-se a análise dos compensadores por observadores de estados como forma de atingir tais objetivos. Mostra-se que, em certas condições, essa estrutura equivale à dos observadores proporcionais-integrais e apresentam-se as condições de estabilidade nominal. Evidencia-se também que é possível tratar esse problema de controle como um problema de "model matching" ou como um problema de controle com dois graus de liberdade. Mostra-se também que o projeto do compensador é equivalente ao projeto de sistemas de controle por realimentação estática da saída. Essa equivalência implica que, embora os compensadores por observadores sejam cômodos à incorporação de especificações temporais, sua estrutura é limitada para garantir que especificações gerais sejam satisfeitas. Contorna-se então essa limitação estendendo-se o estudo ao caso dos compensadores sem essa restrição estrutural. O problema de "model matching" e o problema de controle 2D são considerados como forma indireta de incorporar-se as especificações temporais e condições de projeto são obtidas reduzindo-se os possíveis conservadorismos dos projetos usuais. Ainda neste sentido, formula-se o problema denominado de "model tracking", podendo ser capaz de reduzir ainda mais esses aspectos de conservadorismo. Nessa estrutura, o erro de rastreamento entre a saída do modelo de referência e a saída medida da planta é realimentado, fazendo com que o modelo de referência faça parte explícita do controlador, permitindo ajuste pós-projeto da mesma forma que faz com a estrutura 2D. Toda as condições de projeto são obtidas no domínio da freqüência, em termos de restrições da malha aberta e da malha fechada, permitindo que técnicas padrões de projeto multivariável como LQG/LTR e H¥ possam ser diretamente utilizadas na obtenção do compensador. Obtiveram-se assim metodologias de projeto capazes de garantir robustamente a rejeição do erro de rastreamento de um modelo de referência, além de permitir que especificações usuais como a rejeição dos erros de medida e rejeição dos distúrbios sejam incorporadas no mesmo procedimento de projeto. O controle de um tanque de mistura é usado como exemplo numérico para ilustrar as metodologias de projeto. / This work is concerned with the design of robust multivariable controllers with time domain specifications. As a first step an analysis of controllers based on state observers has been done. It has been shown that this structure is equivalent to the proportional-integral observers. The conditions for nominal stability have then been presented. It has also been shown that this control problem can be seen as a model matching control design with two degrees of freedom. Furthermore it has been shown that compensator design can be reduced to the traditional static output feedback problem. This fact implies that although compensators based on state observers seem to be suitable to deal with time domain specifications, their structure has limitations to guarantee that more general specifications be satisfied. In order to overcome such limitations both the model matching and the 2-D control structures have been considered to include time domain specifications in the design problem. Design conditions have been derived in order to reduce the eventual conservatism associated to the usual design procedure. A control design problem named model tracking has also been formulated with the aim of reducing even more such conservatism. In this new structure the tracking error between the output of the reference model and the measured plant output is fed back. The reference model is then an explicit part of the controller. As a consequence small adjustments can be done on it during system start-up in the same way as with the 2-D structure. All the design conditions have been written in the frequency domain as constraints on both open-loop and closed-loop transfer matrices. Standard multivariable design techniques like LQG/LTR and H¥ can then be used. The proposed design methodology can robustly guarantee tracking of the reference model output as well as both measurement error and disturbance rejections. The control of a mixture tank has been used as a numeric example to illustrate the design methodologies.

The Swedish National Archives are in charge of the management of Common Specifications (CS). CS are genericmetadata specifications that provides structure and markup when transferring digital information betweeninformation systems and to electronic archives. As of now there is no CS for electronic healthcare records (EHR).Organizations around Sweden have developed their own specifications for transferring healthcare information. Inaddition to that, there are comprehensive international EHR metadata standards established. The Swedish NationalArchives have commissioned a study of EHR metadata specifications and standards to aid in the development of theCS.A Delphi study was conducted, including respondents from major archiving organizations in Sweden, to identifynecessary metadata categories when exchanging EHRs. The data was analyzed considering the international EHRmetadata standards HL7 CDA2 and CEN/ISO EN13606, as well as digital preservation metadata categories. Theresults were a set of metadata categories necessary to include in a CS. In addition, a subset of suggested mandatorymetadata categories is proposed and a list of implications for practice. Clinical codes, auditing, and separatingmetadata related to different contexts are a sample size of the implications.The results were evaluated in an interview with the Swedish National Archives, as well as Sydarkivera. Three criteriafor evaluating the results were proposed, being that the results had to consider a common terminology as well as bebased on a metadata standard and Swedish metadata specifications for EHRs. The interview revealed that the resultssatisfied these criterions, except for requiring a study on one additional user environment of EHRs.