Probabilistic timing analysis: An approach using copulas
Probabilistic timing analysis: An approach using copulas
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概率时序分析：使用 copula 的方法
DOI：
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发表时间：
2005
期刊：
影响因子：
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通讯作者：
M. Newby
中科院分区：
文献类型：
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作者：
G. Bernat;A. Burns;M. Newby
现在，对复杂系统的定时分析和调度计划需要工具来处理系统行为是随机的事实，并且包含很难通过分析确定的依赖项。本文介绍了Copulas，这是一种通用统计工具，用于构建多元分布并描述随机变量的依赖性结构。 CoPulas用于解决确定实时程序最差的执行时间的概率分布的问题。对于实时系统来说，统计独立性的普遍假设通常是不正确的，并且导致严重低估了最坏情况的可能性。 Copulas允许描述程序之间的依赖性结构，并且只要无法确定该依赖关系，就可以为它们之间的任何可能依赖性的最坏情况执行时间分布提供下限。该方法通过案例研究说明。
Timing analysis and scheduling for complex systems now requires tools to deal with the fact that systems behaviour is stochastic and contains dependencies which are difficult to determine analytically. This paper introduces copulas, a general statistical tool for constructing multivariate distributions and describing dependence structures of random variables. Copulas are used to solve the problem of determining the probability distribution of the worst-case execution time of a real-time program. The common assumption of statistical independence is generally incorrect for real-time systems and results in severe underestimation of the probability of the worst case. Copulas allow the description of the dependence structure between blocks of a program, and whenever that dependence can not be determined it is possible to provide lower bounds for the distribution of the worst case execution time for any possible dependence between them. The method is illustrated through a case study.