We present novel concepts, technologies and potentials of optical data communication, especially for future computer architectures. The WDM (wavelength division multiplexing) and the optical wiring technologies are ex...
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Safety-related systems mostly comprise hardware and software solutions. Due to the increasing application of complex hardware and software systems, the software systems have to be considered regarding safety as well a...
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Safety-related systems mostly comprise hardware and software solutions. Due to the increasing application of complex hardware and software systems, the software systems have to be considered regarding safety as well as hardware systems. The development of a safety-related software system is similar to the development of a safety-related hardware systems. But there are still no generally accepted methods for developing safety-critical software. One has to use the methods, which fit best to the actual requirements. However, the calculation of reliability and availability for safety-related software systems is far more complex.
Robotic systems have been developed in every field where a further progress was constricted due to the human limitations in terms of speed, precision, fatigue, repeatability, strength, safety etc. One of the pioneer f...
The international standard IEC/61508 provides the developer with guidelines for the design and implementation of safety related systems according to this standard. This standard states qualitative and quantitative cri...
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ISBN:
(纸本)9781424435890
The international standard IEC/61508 provides the developer with guidelines for the design and implementation of safety related systems according to this standard. This standard states qualitative and quantitative criteria in order to judge a safety related system in such a way that safety critical applications can be implemented. This paper details a quantitative criterion which is the probability of failure on low demand, known as PFD. After an introduction into this topic, the principle steps to calculate the probability of failure with the help of reliability block diagrams for different hardware architecture will be detailed and presented. The PFD-equations will be derived for a 1oo1 architecture with the help of MacLaurin series.
This paper revisits a problem that was identified by Kramer and Magee: placing a system in a consistent state before and after runtime changes. We show that their notion of quiescence as a necessary and sufficient con...
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Developing security-critical applications is very difficult and the past has shown that many applications turned out to be erroneous after years of usage. For this reason it is desirable to have a sound methodology fo...
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Developing security-critical applications is very difficult and the past has shown that many applications turned out to be erroneous after years of usage. For this reason it is desirable to have a sound methodology for developing security-critical e-commerce applications. We present an approach to model these applications with the Unified Modeling Language (UML) [1] extended by a UML profile to tailor our models to security applications. Our intent is to (semi-) automatically generate a formal specification suitable for verification as well as an implementation from the model. Therefore we offer a development method seamlessly integrating semi-formal and formal methods as well as the implementation. This is a significant advantage compared to other approaches not dealing with all aspects from abstract models down to code. Based on this approach we can prove security properties on the abstract protocol level as well as the correctness of the protocol implementation in Java with respect to the formal model using the refinement approach. In this paper we concentrate on the modeling with UML and some details regarding the transformation of this model into the formal specification. We illustrate our approach on an electronic payment system called Mondex [10]. Mondex has become famous for being the target of the first ITSEC evaluation of the highest level E6 which requires formal specification and verification.
We elaborate on reasoning in contemporary (semi) automatic parallelizing refactoring. As the main contribution we summarize contemporary approaches and show that all attempts to reason in parallelization thus far, hav...
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We elaborate on reasoning in contemporary (semi) automatic parallelizing refactoring. As the main contribution we summarize contemporary approaches and show that all attempts to reason in parallelization thus far, have amounted to local code analysis given data and control dependencies. We conclude that, by retaining this perspective only, parallelization continues to exploit merely a subset of the reasoning methods available today and is likely to remain limited. To address this problem we suggest to expand the local analyses, such that, they take seriously relations between individual local parallelizing transformations. We argue that such a coupling allows to process sparser parallelizable constructs, such as, producer-consumer coordination. We identify questions to be addressed to put this principle into action and report on-going work on (reasoning) mechanisms able to support this.
All over the world it can be noticed that product miniaturisation is a central theme in product development for different application areas. In robotics scientific research, one of the most important approaches is con...
In this paper, a new multipurpose Lightweight Grid (LWG) system is introduced, under the acronym Computational Basic Reprogrammable Adaptive (CoBRA) grid. It provides the functionality grid users require, and offers g...
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