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排序方式: 共有7472条查询结果,搜索用时 15 毫秒
51.
Chin-Yuan Hu 《Journal of Mathematical Analysis and Applications》2007,328(1):201-219
Recently we established Matysiak and Szablowski's conjecture [V. Matysiak, P.J. Szablowski, Theory Probab. Appl. 45 (2001) 711-713] about a lower bound of real-valued characteristic functions. In this paper, applying an alternative approach we are able to give explicitly the ranges of argument for which the obtained inequalities hold true for general characteristic functions. 相似文献
52.
In this research, we investigate stopping rules for software testing and propose two stopping rules from the aspect of software reliability testing based on the impartial reliability model. The impartial reliability difference (IRD-MP) rule considers the difference between the impartial transition-probability reliabilities estimated for both software developer and consumers at their predetermined prior information levels. The empirical–impartial reliability difference (EIRD-MP) rule suggests stopping a software test when the computed empirical transition reliability is tending to its estimated impartial transition reliability. To insure the high-standard requirement for safety-critical software, both rules take the maximum probability (MP) of untested paths into account. 相似文献
53.
J. Keilson 《Annals of Operations Research》1987,9(1):439-447
A redundant system of independent repairable components with general failure time and repair time distributions is considered. It is shown that the system failure time has an expectation dependent only on the mean failure times and mean repair times of the components and not on their distributions. An intuitive argument is provided, based on the time of onset of the quasi-stationary distribution on the set of working states, to show that for highly reliable systems, the system failure time is exponentially distributed to good approximation. The argument also justifies a simple figure of merit for the quality of the exponential approximation. A key ingredient in the analysis is the system relaxation time, an informal review of which is provided. 相似文献
54.
55.
Carl Boor 《Advances in Computational Mathematics》2006,24(1-4):143-153
A lemma of Micchelli's, concerning radial polynomials and weighted sums of point evaluations, is shown to hold for arbitrary
linear functionals, as is Schaback's more recent extension of this lemma and Schaback's result concerning interpolation by
radial polynomials. Schaback's interpolant is explored.
Happy 60th and beyond, Charlie!
Mathematics subject classifications (2000) 41A05, 41A6. 相似文献
56.
用斜坡电压法(Voltage Ramp, V-ramp)评价了0.18μm双栅极 CMOS工艺栅极氧化膜击穿电量(Charge to Breakdown, Qbd)和击穿电压(Voltage to Breakdown, Vbd). 研究结果表明,低压器件(1.8V)的栅极氧化膜(薄氧)p型衬底MOS电容和N型衬底电容的击穿电量值相差较小,而高压器件(3.3V)栅极氧化膜(厚氧)p衬底MOS电容和n衬底MOS电容的击穿电量值相差较大,击穿电压测试值也发现与击穿电量
关键词:
薄氧
可靠性
击穿电压
击穿电量 相似文献
57.
Howel Tong 《应用数学学报(英文版)》2002,18(2):177-184
Abstract I reflect upon the development of nonlinear time series analysis since 1990 by focusing on five majorareas of development. These areas include the interface between nonlinear time series analysis and chaos,thenonparametric/semiparametric approach,nonlinear state space modelling,financial time series and nonlinearmodelling of panels of time series. 相似文献
58.
Jacquet Philippe Minet Pascale Mühlethaler Paul Rivierre Nicolas 《Wireless Personal Communications》1997,4(1):51-63
Radio LANs are emerging in the computing world. They are supported by distinct configurations: on the one hand radio LANs with base stations and a wired backbone, on the other hand radio LANs implementing Intra-forwarding. Adding a new node in a radio LAN with Intra-forwarding, increases the reliability, while this reliability decreases with ad hoc or hub configurations. This advantage of Intra-forwarding is quantified. Intra-forwarding, as defined in the HIPERLAN standard, is based on a hop-by-hop policy and link check procedures. It is shown how point-to-point packets and broadcast packets are forwarded. The three basic components of Intra-forwarding needed to build and update the Intra-forwarding database are described. The originality of this approach is the use of multipoint relays which enable better scalability. The correctness of the Intra-forwarding protocol is proved and its cost is evaluated. 相似文献
59.
本文给出了单目标多约束下串、并联混合系统中 ,由选取重要单元 (重要度最大的单元 )的方法 ,来提高系统可靠度的有效优化判定模型及算法 ,用同样思想给出了串、并联系统中冗余度的优化判定模型及算法 相似文献
60.
电子设备中表面安装器件和电路基板以及焊接材料的热膨胀系数差异,使得SMT互连组件在热循环条件下产生热膨胀失配,在焊接处产生热应力,在长时间的交变应力的作用下,焊接处遭到疲劳破坏而使设备工作失效,这就是SMT互连组件在热循环条件下的基本失效机理。文中还介绍了美国MIL—HDBK—217F NOTICE Ⅱ公布的表面安装连接组件可靠性预测lSMT模型。给出一系列具有实用价值的参数。 相似文献