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411.
以软件研制的生命周期为背景,探讨利用仿真模型对软件可靠性进行研究的方法.文章阐述了仿真模型分析方法与传统的模型分析方法的不同之处,通过对软件可靠性过程的分析,设计了一个基本的仿真器结构,由此考察引发失效行为的各种故障因素及其对软件可靠性的影响. 相似文献
412.
413.
针对大型项目多峰、复杂费用分布的传统仿真建模方法模型选取过于复杂、且难以达到精度要求等不足,提出将一种基于支持向量机的机器学习方法应用于大型复杂武器系统研制费投资分布研究.计算结果表明,这种方法有效弥补了传统建模方法的缺陷,有更好的泛化能力和实用性,因而可以作为研究此类问题的一种新方法. 相似文献
414.
普通物理实验考核方法的探索和实践 总被引:1,自引:1,他引:1
结合实验教学的特点,探索并建立了一套行之有效的大学物理实验考核方法,在实践中取得了教好的效果。 相似文献
415.
导弹综合测试是检测导弹性能质量较为有效的方法和手段。实施综合测试的设备,通常称作导弹测试系统。导弹测试系统的应用范畴,针对性较强,每种型号的导弹,均有其对应型号的测试系统。导弹技术在不断更新和发展,导弹测试系统的性能也必须不断向前发展。如何提高测试系统的技术水平,已日益为科研工作者所关注。就导弹测试系统方案设计的相关问题,进行了概要性讨论。 相似文献
416.
One of the major problems in modeling production systems is how to treat the job arrival process. Restrictive assumptions such as Markovian arrivals do not represent real world systems, especially if the arrival process is generated by job departures from upstream workstations. Under these circumstances, cost‐effective policies that are robust with respect to the nature of the arrival process become of interest. In this paper, we focus on minimizing the expected total holding and setup costs in a two‐stage produce‐to‐order production system operated by a cross‐trained worker. We will show that if setup times are insignificant in comparison with processing times, then near‐optimal policies can be generated with very robust performances with respect to the arrival process. We also present conditions under which these near‐optimal policies can be obtained by using only the arrival and service rates. © 2004 Wiley Periodicals, Inc. Naval Research Logistics, 2005. 相似文献
417.
Most modern processes involve multiple quality characteristics that are all measured on attribute levels, and their overall quality is determined by these characteristics simultaneously. The characteristic factors usually correlate with each other, making multivariate categorical control techniques a must. We study Phase I analysis of multivariate categorical processes (MCPs) to identify the presence of change‐points in the reference dataset. A directional change‐point detection method based on log‐linear models is proposed. The method exploits directional shift information and integrates MCPs into the unified framework of multivariate binomial and multivariate multinomial distributions. A diagnostic scheme for identifying the change‐point location and the shift direction is also suggested. Numerical simulations are conducted to demonstrate the detection effectiveness and the diagnostic accuracy.© 2013 Wiley Periodicals, Inc. Naval Research Logistics, 2013 相似文献
418.
We investigate the solvability of two single‐machine scheduling problems when the objective is to identify among all job subsets with cardinality k,1≤k≤n, the one that has the minimum objective function value. For the single‐machine minimum maximum lateness problem, we conclude that the problem is solvable in O(n2) time using the proposed REMOVE algorithm. This algorithm can also be used as an alternative to Moore's algorithm to solve the minimum number of tardy jobs problem by actually solving the hierarchical problem in which the objective is to minimize the maximum lateness subject to the minimum number of tardy jobs. We then show that the REMOVE algorithm cannot be used to solve the general case of the single‐machine total‐weighted completion time problem; we derive sufficient conditions among the job parameters so that the total weighted completion time problem becomes solvable in O(n2) time. © 2013 Wiley Periodicals, Inc. Naval Research Logistics 60: 449–453, 2013 相似文献
419.
Accelerated life testing (ALT) using multiple stresses is commonly used in practice to resemble the operating stresses at normal operating conditions and obtain failure observations in a much shorter time. However, to date, there is little research into the theory of planning ALT for reliability estimation with multiple stresses. ALT with multiple stresses can result in a large number of stress‐level combinations which presents a challenge for implementation. In this article, we propose an approach for the design of ALT plans with multiple stresses and formulate multistress test plans based on different objectives and practical constraints. We develop a simulated annealing algorithm to efficiently determine the testing plan parameters. We demonstrate the proposed method with examples based on an actual test conducted using three stress types. The obtained optimal test plans are compared with those based on fractional factorial design. © 2013 Wiley Periodicals, Inc. Naval Research Logistics 60: 468–478, 2013 相似文献
420.
张建勋 《中国人民武装警察部队学院学报》2010,26(6):39-40
自动喷水灭火系统末端试水装置直接影响系统的启动、报警及联动等功能的测试和检验,增压设施则关系到系统供水的可靠性。结合应用实际,提出了系统设计中的问题,分析其原因并提出了应对措施。 相似文献