Interface de software para sistemas de controle a eventos discretos

Sistemas a Eventos Discretos estão dia após dia mais presentes na nossa vida. Para garantir o funcionamento desses sistemas, uma das teorias que vem sendo usada é a Teoria de Controle Supervisório, que tem se mantido mais restrita a área acadêmica. Nesse trabalho foram então analisadas arquiteturas de Sistemas de Controle a Eventos Discretos e suas implementações na literatura. Foi então proposta e implementada em hardware portátil a modularização de uma dessas arquiteturas, através de uma interface, com o objetivo de facilitar futuros desenvolvimentos na área. Foram apresentados os materiais e métodos utilizados, uma visão global da implementação e seus principais detalhes. Foi feita uma comparação com sistemas já existentes para a validação da implementação, além de um exemplo de como a proposta pode facilitar o trabalho na área. Por fim, foram propostos novos desenvolvimentos tanto na área de Sistemas de Controle a Eventos Discretos como no desenvolvimento dessa interface.Discrete Events Systems are day after day more present in our lives. To ensure their proper functioning, one of the current theories being used is the Supervisory Control Theory, which has remained restricted to the Academia. In this paper, Discrete Events Control Systems architectures and their implementations in the litearature were analyzed. Then, a modularized version of one of these architectures was proposed and implemented in mobile hardware through an interface, with the objective of facilitating future developments in the area. The materials and methods employed were presented as well as an overview of the implementation and its details. A comparison with an already existing system was made to validate the implementation, and also an example of how this proposal can facilitate the work in the area was given. In the end, new developments were proposed, both in the Discrete Events Control Systems domain as well as in the developed interface

Exogenous Coordination of Concurrent Software Components with JavaBIP

A strong separation of concerns is necessary in order to make the design of domain-specific functional components independent from cross-cutting concerns, such as concurrent access to the shared resources of the execution platform. Native coordination mechanisms, such as locks and monitors, allow developers to address these issues. However, such solutions are not modular, they are complex to design, debug and maintain. We present the JavaBIP framework that allows developers to think on a higher level of abstraction and clearly separate the functional and coordination aspects of the system behavior. It implements the principles of the BIP component framework rooted in rigorous operational semantics. It allows the coordination of existing concurrent software components in an exogenous manner, relying exclusively on annotations, component APIs and external specification files. We introduce the annotation and specification syntax of JavaBIP and illustrate its use on realistic examples; present the architecture of our implementation, which is modular and easily extensible; provide and discuss performance evaluation results

Modelling Architecture Styles

Software systems tend to increase over time in size and complexity. Their development usually spans a long period of time and often results in systems that are hard to understand, debug and maintain. Architectures are common means for organising coordination between components in order to build complex systems and make them manageable. They allow thinking on a higher plane and avoiding low-level mistakes. Grouping architectures that share common characteristics into architecture styles assists component re-use and thus, the cost-effective development of systems. Additionally, architecture styles provide means for ensuring correctness-by-construction by enforcing global properties. The main goal of this thesis is to propose and study formalisms for modelling architectures and architecture styles. For the specification of architectures, we study interaction logics, which are Boolean algebras on a set of component actions. We study a modelling methodology based on first-order interaction logic for writing architecture constraints. To validate the applicability of the approach, we developed the JavaBIP framework that integrates architectures into mainstream software development. JavaBIP receives as input architecture specifications, which it then uses to coordinate software components without requiring access to their source code. JavaBIP implements the principles of the BIP component framework. For the specification of architecture styles, we propose configuration logics, which are powerset extensions of interaction logic. Propositional configuration logic formulas are generated from formulas of interaction logic by using the operators union, intersection and complementation, as well as a coalescing operator. We provide a complete axiomatisation of the propositional configuration logic and a decision procedure for checking that an architecture satisfies given logical specifications. To allow genericity of specifications, we study higher-order extensions of the propositional configuration logic. We provide several examples illustrating the application of configuration logics to the characterisation of architecture styles. For the specification of architecture styles, we also propose architecture diagrams, which is a graphical language rooted in rigorous semantics. We provide methods to assist software developers to specify consistent architecture diagrams, generate the conforming architectures of a style and check whether an architecture model meets given style requirements. We present a full encoding of architecture diagrams into configuration logics. Finally, we report on applications of architecture diagrams to modelling architecture styles identified in realistic case studies of on-board satellite software