Made available in DSpace on 2014-06-12T15:52:36Z (GMT). No. of bitstreams: 1 license.txt: 1748 bytes, checksum: 8a4605be74aa9ea9d79846c1fba20a33 (MD5) Previous issue date: 2009 / Devido á grande demanda por softwares cada vez mais robustos, complexos e flexíveis, e, sobretudo, pelo curtíssimo tempo de entrega exigido, a engenharia de software tem procurado novos meios de desenvolvimento que supram satisfatoriamente essas demandas. Uma forma de galgar esses novos patamares de produtividade provém do uso de uma metodologia baseada em agentes que se comunicam e com isso, ao invés dos programas serem estritamente programados, o comportamento destes sistemas de software emerge da interação de agentes, robôs, ou subsistemas aut onomos, independentes, além de declarativamente especificados. Isto provê a habilidade para automaticamente configurá -los, otimizá-los, monitorá-los, adaptá-los, diagnosticá-los, repará-los e protegê-los dentro do ambiente. Contudo, um grande problema das linguagens declarativas é a falta de mecanismos que permitem a melhor estruturação de dados, facilitando portanto, o reuso. Portanto, esta dissertação explica o desenvolvimento de nova linguagem lógica declarativa para programar sistemas de raciocínio automático de uma forma modularizada: C2HR∨. A linguagem base escolhida para a extensão com componentes lógicos foi CHR. Os motivos para essa escolha são definidos ao longo da dissertação. Duas abordagens, portanto, são apresentadas: a primeira, conhecida como CHRat, foi desenvolvida numa parceria juntamente com o grupo de pesquisas CONTRAINTES do INRIA/Rocquencourt-Paris, onde o programador ´e o responsável direto por definir os componentes CHR, permitindo o seu reuso por outros componentes; a segunda aplicação, CHRtp, visa atender prioritariamente requisitos de completude e, por isso, se baseia em procedimentos lógicos de inferência como: o raciocínio para frente, o raciocínio para trás, e a resolução/factoring. A dissertação mostra também alguns exemplos práticos, onde uso de componentes facilita radicalmente sua implementação. As contribuições almejadas com essa dissertação são: a definição de uma família bem formalizada de provadores de teoremas automáticos, que podem trabalhar com sentenças especificadas em lógica horn ou em lógica de primeira ordem, a extensão de CHR como uma linguagem modular de propósito geral, a melhor estruturação de bases conhecimentos e até o uso em conjunto de bases heterogêneas, a definição de uma linguagem para a fácil e direta estruturação de dados por meio de componentes, dentre outras

Component-based software engineering is becoming a prominent solution to the development of complex embedded systems. Since it allows a system to be built by reusable and independently developed components, component-based development substantially facilitates the development of a complex embedded system and allows its complexity to be better managed. Meanwhile, partitioning system behavior into multiple operational modes is also an effective approach to reducing system complexity. Combining the component-based approach with the multi-mode approach, we get a component-based multi-mode system, for which a key issue is its mode switch handling. The mode switch of such a system corresponds to the joint mode switches of many hierarchically organized components. Such a mode switch is not trivial as it amounts to coordinate the mode switches of different components that are independently developed. Since most existing approaches to mode switch handling assume that mode switch is a global event of the entire system, they cannot be easily applied to component-based multi-mode systems where both the mode switch of the system and each individual component must be considered, and where components cannot be assumed to have global knowledge of the system. In this thesis, we present a mechanism---the Mode Switch Logic (MSL)---which provides an effective solution to mode switch in component-based multi-mode systems. MSL enables a multi-mode system to be developed in a component-based manner, including (1) a mode-aware component model proposed to suit the multi-mode context; (2) a mode mapping mechanism for the seamless composition of multi-mode components and their mode switch guidance; (3) a mode switch runtime mechanism which coordinates the mode switches of all related components so that the mode switch can be correctly and efficiently performed at the system level; and (4) a timing analysis for mode switches realized by MSL. All the essential elements of MSL are additionally demonstrated by a case study. / ARROWS

In software engineering, system construction typically starts from a requirements specification that has been engineered from raw requirements in a natural language. The specification is used to derive intermediate requirements models such as structured or object-oriented models. Throughout the stages of system construction, these artefacts will be used as reference models. In general, in order to derive a design specification out of the requirements, the entire set of requirements specifications has to be analysed. Such models at best only approximate the raw requirements since these design models are derived as a result of the abstraction process according to the chosen software development methodology, and subjected to the expertise, intuition, judgment and experiences of the analysts or designers of the system. These abstraction models require the analysts to elicit all useful information from the requirements, and there is a potential risk that some information may be lost in the process of model construction. As the use of natural language requirements in system construction is inevitable, the central focus of this study was to use requirements stated in natural language in contrast to any other requirements representation (e.g. modelling artefact). In this thesis, an approach that avoids intermediate requirements models, and maps natural language requirements directly into architectural constructs, and thus minimises information loss during the model construction process, has been defined. This approach has been grounded on the adoption of a component model that supports incremental composition. Incremental composition allows a system to be constructed piece by piece. By mapping a raw requirement to elements of the component model, a partial architecture that satisfies that requirement is constructed. Consequently, by iterating this process for all the requirements, one at a time, the incremental composition to build the system piece by piece directly from the requirements can be achieved. In software engineering, system construction typically starts from a requirements specification that has been engineered from raw requirements in a natural language. The specification is used to derive intermediate requirements models such as structured or object-oriented models. Throughout the stages of system construction, these artefacts will be used as reference models. In general, in order to derive a design specification out of the requirements, the entire set of requirements specifications has to be analysed. Such models at best only approximate the raw requirements since these design models are derived as a result of the abstraction process according to the chosen software development methodology, and subjected to the expertise, intuition, judgment and experiences of the analysts or designers of the system. These abstraction models require the analysts to elicit all useful information from the requirements, and there is a potential risk that some information may be lost in the process of model construction. As the use of natural language requirements in system construction is inevitable, the central focus of this study was to use requirements stated in natural language in contrast to any other requirements representation (e.g. modelling artefact). In this thesis, an approach that avoids intermediate requirements models, and maps natural language requirements directly into architectural constructs, and thus minimises information loss during the model construction process, has been defined. This approach has been grounded on the adoption of a component model that supports incremental composition. Incremental composition allows a system to be constructed piece by piece. By mapping a raw requirement to elements of the component model, a partial architecture that satisfies that requirement is constructed. Consequently, by iterating this process for all the requirements, one at a time, the incremental composition to build the system piece by piece directly from the requirements can be achieved.

In order to model check a software component which is not a standalone program, we need a model of the software which completes the program. This problem is important for software engineers who need to deploy an existing component into a new environment. The model is typically generated by abstracting the surrounding software environment in which the component will be executed. However, abstracting the surrounding software is a difficult and error-prone task, particularly when the surrounding software is a complex software artifact which can not be easily abstracted. In this dissertation, we present a new approach to the problem by abstracting the software component under test and leaving the surrounding software concrete. We derive this abstract-concrete mixed model automatically for both sequential and concurrent C programs and verify them using the SPIN model checker. We give verification results for several components under test contained within complex software environments to demonstrate the strengths and weaknesses of our approach. We are able to find errors in components which were too complex for analysis by existing model checking techniques. We prove that this mixed abstract-concrete model can be bisimilar to the original complete software system using an abstraction refinement scheme. We then show how to generate test cases for the component under test using this abstraction refinement process.

No description available.

No description available.

In a parameterized collaboration design, one views software as a collection of components that play specific roles in interacting, giving rise to collaborative behavior. From this perspective, collaboration designs revolve around reusing collaborations that typify certain design patterns. Unfortunately, verifying that active, concurrently executing components obey the synchronization and communication requirements needed for the collaboration to work is a serious problem. At least two major complications arise in concurrent settings: (1) it may not be possible to analytically identify components that violate the synchronization constraints required by a collaboration, and (2) evolving participants in a collaboration independently often gives rise to unanticipated synchronization conflicts. This work presents a solution technique that addresses both of these problems. Local (that is, role-to-role) synchronization consistency conditions are formalized and associated decidable inference mechanisms are developed to determine mutual compatibility and safe refinement of synchronization behavior. More specifically, given generic parameterized collaborations and components with specific roles, mutual compatibility analysis verifies that the provided and required synchronization models are consistent and integrate correctly. Safe refinement, on the other hand, guarantees that the local synchronization behavior is maintained consistently as the roles and the collaboration are refined during development. This form of local consistency is necessary, but insufficient to guarantee a consistent collaboration overall. As a result, a new notion of global consistency (that is, among multiple components playing multiple roles) is introduced: causal process constraint analysis. A method for capturing, constraining, and analyzing global causal processes, which arise due to causal interference and interaction of components, is presented. Principally, the method allows one to: (1) represent the intended causal processes in terms of interactions depicted in UML collaboration graphs; (2) formulate constraints on such interactions and their evolution; and (3) check that the causal process constraints are satisfied by the observed behavior of the component(s) at run-time. / Ph. D.

<p>The main goal of this thesis is to investigate efficient searching mechanisms for searching and retrieving software components across different remote repositories and implement a supporting prototype called “Component Repository Browser” using the plug-in based Eclipse technology for PROGRESS-IDE. The prototype enables users to search the ProCom components and to import the desired components from a remote repository server over different protocols such as HTTP, HTTPS, and/or SVN. Several component searching mechanisms and suggestions were studied and examined such as keyword, facet-based search, folksonomy classification, and signature matching, from which we selected keyword search along with facet-based searching technique to help component searchers to efficiently find the desired components from a remote repository.</p>

The main goal of this thesis is to investigate efficient searching mechanisms for searching and retrieving software components across different remote repositories and implement a supporting prototype called “Component Repository Browser” using the plug-in based Eclipse technology for PROGRESS-IDE. The prototype enables users to search the ProCom components and to import the desired components from a remote repository server over different protocols such as HTTP, HTTPS, and/or SVN. Several component searching mechanisms and suggestions were studied and examined such as keyword, facet-based search, folksonomy classification, and signature matching, from which we selected keyword search along with facet-based searching technique to help component searchers to efficiently find the desired components from a remote repository.

The thesis deals with the modeling of the Component Based Software (CBS) systems in the UML language and with extension of the UML language with using of meta-modeling techniques and with using of the UML Prodile technology. Thesis also deals with Component Based Development (CBD). The main part of this study deals with specifying of methodology for creating of UML Prodiles and with demonstration of this methodology on selected Component System meta-model by creating the profile including the OCL constraints and description of problems with creating of the prodile. Thesis also describes support of the UML Profile technology in existing UML CASE tools. For demonstration purposes thesis contains the case study with example which uses in this work created UML Profile. Profile is created in accordance with specification of UML version 2.3 and OCL in version 2.2. Demonstration is performed and profile itself is created using IBM Rational Software Architect version 8.0.2.