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Multimedia Tools and Applications - Ubiquitous and networked sensors impose a huge challenge for privacy protection which has become an emerging problem of modern society. Protecting the privacy of... 相似文献
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Bernhard Kaiser Catharina Gramlich Marc Frster 《Reliability Engineering & System Safety》2007,92(11):1521-1537
Safety models for software-controlled systems should be intuitive, compositional and have the expressive power to model both software and hardware behaviour. Moreover, they should provide quantitative results for failure or hazard probabilities. Fault trees are an accepted and intuitive model for safety analysis, but they are incapable of expressing state dependencies or temporal order of events. We propose to combine fault trees with an explicit State/Event semantics, using a graphical notation that is similar to Statecharts. Our new model, named State/Event Fault Trees (SEFTs), subsumes both deterministic state machines suited to describe software behaviour, and Markov chains that model probabilistic failures, while keeping the visualisation of causal chains known from fault trees. We allow exponentially distributed probabilistic events, deterministic delays, and triggered events. The model provides a component concept, where components are connected by typed ports. Quantitative evaluation is achieved by translating the component models to Deterministic and Stochastic Petri Nets (DSPNs) and using an existing tool for analysis or simulation. This paper, which is an extended version of [Kaiser B, Gramlich C. State-Event-Fault-Trees—a safety analysis model for software controlled systems. Computer safety, reliability, and security. Proceedings of the 23rd international conference, SAFECOMP 2004, Potsdam, Germany, September 21st–24th. Lecture Notes in Computer Science, vol. 3219, 2004.p. 195–209], revisits the model elements and the analysis procedure and provides a small case study of a fire alarm system, completed by an outlook on our tool project ESSaRel. 相似文献
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Colzato Lorenza S.; Raffone Antonino; Hommel Bernhard 《Canadian Metallurgical Quarterly》2006,32(3):705
Four experiments were conducted to investigate the relationship between the binding of visual features (as measured by their aftereffects on subsequent binding) and the learning of feature-conjunction probabilities. Both binding and learning effects were obtained, but they did not interact. Interestingly, (shape-color) binding effects disappeared with increasing practice, presumably because of the fact that only 1 of the features involved was relevant to the task. However, this instability was only observed for arbitrary, not highly overlearned combinations of simple geometric features and not for real objects (colored pictures of a banana and strawberry), where binding effects were strong and resistant to practice. These findings suggest that learning has no direct impact on the strength or resistance of bindings or on speed with which features are bound; however, learning does affect the amount of attention particular feature dimensions attract, which again can influence which features are considered in binding. (PsycINFO Database Record (c) 2011 APA, all rights reserved) 相似文献
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Different acid solids loaded with 1 wt.% of Pt have been studied in n-heptane hydroisomerization in order to determine the influence of porosity and acidity (considered measured by the activity) on selectivities. The open solids like Y and β zeolites and a pillared clay present different activities towards n-C7 conversion but similar selectivities. Consequently, acidity seems to be a less important parameter in n-C7 isomerization than porosity. Very different results were obtained as a function of the solid structure and so n-heptane hydroconversion appears to be a simple and rapid method to obtain data concerning the porosity of unknown zeolite structures. The highest content of multibranched isomers was obtained on open solids but the value predicted by the thermodynamic was never reached due to the fact that cracking of multibranched isomers is initiated quickly. 相似文献
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2-(2′-Hydroxyphenyl)-benzotriazoles, containing a carbonamide group in 5- or 5′-position, were synthesized to stabilize polyamides. The influence of the ortho-positioned hydroxy group for the stabilizing effect of these substances was examined by methylating it. The synthesized benzotriazoles were characterized, especially with regard to their UV-absorption-spectra. The photolytic resistance of poly-(m-phenyleneisophthalamide), containing these stabilizers, for example 2-(2′-hydroxy-5′-tert-butylphenyl)-benzotriazol-5-carbonic acid anilide, was examined by measuring the viscosity. 相似文献