Wyniki wyszukiwania - BazTech

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Modeling Communication with Synchronized Environments

Seceleanu T., Jantsch A.

Fundamenta Informaticae

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2008

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Vol. 86, nr 3

343-369

EN

A deterministic behavior of systems composed of several modules is a desirable design goal. Assembling a complex system from components requires also a high degree of re-usability. The compatibility of the selected components may become a problem even at abstract design levels, due to possible different degrees of model determinacy, possible different execution models, etc. In this cases, an overall deterministic system behavior is difficult to achieve. The development of communication mechanisms between such components will have then to accommodate the differences, so that both correct processing and information exchange (data and control, appropriate choices and relative timing or sequencing) are achieved. For instance, human-machine interaction offers a good example of cooperation between deterministic models (machines) communicating with highly non-deterministic counterparts (the human models, if not restricted). We analyze here such communication mechanisms by "confronting" synchronized and un-synchronized models of execution, in the framework of action systems, a state based formalism. We "force" the two models to coexist within the same context and explore the possibilities of building trustworthy communication channels between them. We base our approach on a combined polling - interrupt scheme, which allows us to mitigate communication issues that may otherwise compromise the correct input-output system behavior. More robust system models are obtained by applying specific correctness rules of refinement. We illustrate our methods on an audio system example, implementable as either a software or a hardware device.

2

Proekologiczny podsystem logistyczny dowolnego systemu działania

Niziński S., Ligier K.

Technical Sciences. Supplement / University of Warmia and Mazury in Olsztyn

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2004

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suppl. 1

173-186

PL

Praca jest poświęcona problemowi ograniczenia zanieczyszczenia środowiska naturalnego z wykorzystaniem racjonalnie zorganizowanego systemu logistycznego. Rozpatrzono zagadnienia dotyczące roli i zadań systemów: logistycznego, eksploatacji, diagnostyki, ochrony środowiska i zagospodarowania odpadów.

EN

The paper deals with the problem of environmental pollution reduction using a rationally organized logistic system. The questions concerning the role and objectives of the following systems: logistic, diagnostic, extraction/exploitation, environmental protection and waste management are discussed.

3

A foundation for refining concurrent objects

Büchi M., Sekerinski E.

Fundamenta Informaticae

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2000

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Vol. 44, Nr 1,2

25-61

EN

We study the notion of class refinement in a concurrent object-oriented setting. Our model is based on a combination of action systems and classes. An action system describes the behavior of a concurrent, distributed, or interactive system in terms of the atomic actions that can take place during the execution of the system. Classes serve as templates for creating objects. To express concurrency with objects, we add actions to classes. We define class refinement based on trace refinement of action systems. Additionally, we give a simulation-based proof rule. We show that the easier to apply simulation rule implies the trace-based definition of class refinement. Class refinement embraces algorithmic refinement, data refinement, and atomicity refinement. Atomicity refinement allows us to split large atomic actions into several smaller ones. Thereby, it paves the way for more parallelism. We investigate the special case of atomicity refinement by early returns in methods.