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101.
Krieshok Thomas S.; Arnold John J.; Kuperman Bernard D.; Schmitz Nancy K. 《Canadian Metallurgical Quarterly》1988,35(2):211
We respond to Cochran's critique of our 1986 study, which was in part a replication of Cochran's original grid methodology for the study of career values. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
102.
System reliability is evolving as an important design method for selecting components and topology. It should be used to investigate the original intact structure behavior as well as providing sufficient reserve capacity under likely accident and damage scenarios. Highway bridges are an area of special concern since effort to optimize the cost of construction may not provide adequate redundant capacity. The paper describes an example in which a typical girder bridge structure is optimized (both size and girder spacing) to achieve target system performance. System reliability constraints are imposed on the behavior of the intact structure under highway loads. Also, residual system reliability constraints are imposed to control safety under specified accident scenarios corresponding to damage and “lost” members due to corrosion, fatigue, fire or accidental collisions. An optimal design framework for controlling safety under all these life cycle situations is thus provided. 相似文献
103.
104.
环境因子的定义及研究现状 总被引:12,自引:0,他引:12
胡斌 《太赫兹科学与电子信息学报》2003,1(1):88-92
从普遍接受的三个基本假设出发,讨论环境因子的定义和失效机理不变的约束条件,重点综述环境因子的研究现状和常用方法,并探讨引入反应论模型解决环境因子预测问题的可能途径。 相似文献
105.
Seong-Min Lee 《Metals and Materials International》2006,12(6):513-516
Based on empirical data, the present work provides a model to prevent filler-induced reliability degradation in plastic-encapsulated
LOC (lead-on-chip) packages. According to the model, the maximum size of the silica fillers included in the plastic package
body should be smaller than one half of the inter-distance between the device and its overlying lead-frame. In particular,
it is shown in the model that the spherical silica particles, which are sometimes trapped in the space between the top surface
of the device and the bottom of the lead-frame during the encapsulating process, can induce huge compressive stress on a specific
site of the integrated circuit pattern due to the thermal shrinkage of the plastic package body. Further, the present model
suggests that tiny fillers squeezed beneath a large trapping filler might directly attack the brittle layer of the device
pattern because the compressive force from the large filler particle can develop into huge compressive stress due to the reduced
load-carrying area. 相似文献
106.
Ettenhofer Mark L.; Hambrick David Z.; Abeles Norman 《Canadian Metallurgical Quarterly》2006,20(5):607
A number of methodological questions have been raised about the reliability and validity of measuring executive functioning (EF) across multiple time points. In this study, correlational and latent-variable analyses were used to examine test-retest reliability of 5 common measures of EF and the stability of a latent EF construct. One hundred eighteen nondemented older adults were tested twice over a 4- to 8-week period. Findings demonstrated modest reliability of individual EF measures but very high stability of a latent EF construct. Relative contributions of each measure to the latent EF factor did not change across measurement trials. In addition, age-related effects on EF were similar at the 2 time points and were within the expected range. Implications for future studies of EF are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
107.
介绍了LC4L-20增压中冷柴油机的性能与结构特点,着重分析了增压中冷技术,及各主要运动件的可靠性设计。 相似文献
108.
Allen M. Johnson Michael A. Schoenfelder David J. Lebold 《Quality and Reliability Engineering International》1993,9(1):55-62
The Rainbow net simulation technique is applied to modelling the impact of system load and fault handling on the availability of a fault-tolerant multiprocessor architecture. Rainbow nets are described along with the motivation for creating this modelling technique. A Rainbow net fault-handling model is created for the fault-tolerant multiprocessor architecture and the topology is shown to remain constant in size, independent of the number of processor, memory and I/O elements configured in the system. Simulation is performed with a varying load in terms of the number of active jobs the system must support. Results are given showing how the fault-tolerant capability varies with load. Two new metrics for evaluating fault tolerance are introduced; namely full fault-tolerability and partial fault-tolerability. They are based on simple observations in the model. 相似文献
109.
Liping Wang Ramana V. Grandhi Dale A. Hopkins 《International journal for numerical methods in engineering》1995,38(10):1721-1738
The objective of this paper is to conduct reliability-based structural optimization in a multidisciplinary environment. An efficient reliability analysis is developed by expanding the limit functions in terms of intermediate design variables. The design constraints are approximated using multivariate splines in searching for the optimum. The reduction in computational cost realized in safety index calculation and optimization are demonstrated through several structural problems. This paper presents safety index computation, analytical sensitivity analysis of reliability constraints and optimization using truss, frame and plate examples. 相似文献
110.