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821.
Several problems in the assignment of parallel redundant components to systems composed of elements subject to failure are considered. In each case the problem is to make an assignment which maximizes the system reliability subject to system constraints. Three distinct problems; are treated. The first is the classical problem of maximizing system reliability under total cost or weight constraints when components are subject to a single type of failure. The second problem deals with components which are subject to two types of failure and minimizes the probability of one mode of system failure subject to a constraint on the probability of the other mode of system failure. The third problem deals with components which may either fail to operate or may operate prematurely. System reliability is maximized subject to a constraint ori system safety. In each case the problem is formulated as an integer linear program. This has an advantage over alternative dynamic programming formulations in that standard algorithms may be employed to obtain numerical results.  相似文献   
822.
This paper deals with the analysis of a model for studying the probability of survival of a subterranean target under an intensive attack. Most of the analysis is based on the assumption that the explosions are circularly distributed about the target and that the number of explosions is known. In the last two sections it is shown what effect a relaxation of these assumptions has on the probability of survival of the target.  相似文献   
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Pine RN 《哈佛国际评论》1994,16(4):26-7, 77
As it has grappled with issues of population policy, the international community has emphasized that women's reproductive rights are human rights. Scholars have also acknowledged that the right to reproductive health care exists within the scope of international human rights treaties and conventions and that gender equality, nondiscrimination, and freedom from government interference in marriage and family life are also guaranteed. Further protections extend to counseling and health information and referral. The Programme of Action of the 1994 International Conference on Population and Development continues this trend by emphasizing the importance of human rights for attaining population and development objectives, calling on governments to focus their efforts on improving the quality of life for individuals, and endorsing the notion that reproductive rights are universal human rights. Reproductive health care options are also influenced by sovereign laws that restrict availability of contraception, sterilization, or abortion. However, universal rights and unrestricted access must be complemented by other factors controlled by domestic laws to guarantee reproductive choice. Such laws cover issues like marriage age, divorce, marital property, child support, maternity benefits, day care, sex discrimination, eligibility for insurance, confidentiality, spousal consent, rape, and sexual abuse. Countries must modify restrictive national laws and promote laws protecting women's rights.  相似文献   
829.
We consider the stochastic linear knapsack problem in which costs are known with certainty but returns are independent, normally distributed random variables. The objective is to maximize the probability that the overall return equals or exceeds a specified target value. A previously proposed preference order dynamic programming-based algorithm has been shown to be potentially suboptimal. We offer an alternative hybrid DP/branch-and-bound algorithm that both guarantees optimality and significantly outperforms generating the set of Pareto optimal returns.© 1993 John Wiley & Sons, Inc.  相似文献   
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