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351.
We consider the multiple-attribute decision problem with finite action set and additive utility function. We suppose that the decision maker cannot specify nonnegative weights for the various attributes which would resolve the problem, but that he/she supplies ordinal information about these weights which can be translated into a set of linear constraints restricting their values. A bounded polytope W of feasible weight vectors is thus determined. Supposing that each element of W has the same chance of being the “appropriate one,” we compute the expected utility value of each action. The computation method uses a combination of numerical integration and Monte Carlo simulation and is equivalent to finding the center of mass of the bounded polytope W . Comparisons are made with another criterion already presented, the comparative hyper-volume criterion, and two small examples are presented.  相似文献   
352.
This paper models a k-unit service system (e.g., a repair, maintenance, or rental facility) with Poisson arrivals, exponential service times, and no queue. If we denote the number of units that are busy as the state of the system, the state-dependent pricing model formalizes the intuitive notion that when most units are idle, the price (i.e., the service charge per unit time) should be low, and when most units are busy, the price should be higher than the average. A computationally efficient algorithm based on a nonlinear programming formulation of the problem is provided for determination of the optimal state-dependent prices. The procedure ultimately reduces to the search on a single variable in an interval to determine the unique intersection point of a concave increasing function and a linear decreasing function. The algorithm takes, on the average, only about 1/2 second per problem on the IBM 360/65 (FORTRAN G Compiler). A discrete optimal-control approach to the problem is shown to result in essentially the same procedure as the nonlinear-programming formulation. Several properties of the optimal state-dependent prices are given. Comparisons of the optimal values of the objective function for the state-dependent and state-independent pricing policies show that the former is on the average, only about 0.7% better than the latter, which may explain partly why state-dependent pricing is not prevalent in many service systems. Potential generalizations of the model are discussed.  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   
355.
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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The present study focuses on the mitigation of shock wave using novel geometric passages in the flow field. The strategy is to produce multiple shock reflections and diffractions in the passage with minimum flow obstruction, which in turn is expected to reduce the shock wave strength at the target location. In the present study the interaction of a plane shock front (generated from a shock tube) with various geometric designs such as, 1) zig-zag geometric passage, 2) staggered cylindrical obstructions and 3) zig-zag passage with cylindrical obstructions have been investigated using computational technique. It is seen from the numerical simulation that, among the various designs, the maximum shock attenuation is produced by the zig-zag passage with cylindrical obstructions which is then followed by zig-zag passage and staggered cylindrical obstructions. A comprehensive investigation on the shock wave reflection and diffraction phenomena happening in the proposed complex passages have also been carried out. In the new zig-zag design, the initial shock wave undergoes shock wave reflection and diffraction process which swaps alternatively as the shock front moves from one turn to the other turn. This cyclic shock reflection and diffraction process helps in diffusing the shock wave energy with practically no obstruction to the flow field. It is found that by combining the shock attenuation ability of zig-zag passage (using shock reflection and diffraction) with the shock attenuation ability of cylindrical blocks (by flow obstruction), a drastic attenuation in shock strength can be achieved with moderate level of flow blocking.  相似文献   
360.
Facing nearly half a billion dollars in spending cuts over the next five years, US defense planners and strategists must simultaneously rebuild a war-weary Army weakened from over a decade of war, build new sea and air capabilities for the Pacific theater, and reduce manpower, procurement, and contractor budgets while promoting innovation. The US defense department is embarking on what may be the most sweeping period of defense transformation in recent memory. This article reviews the history of American defense transformation, focusing on an important but largely overlooked period of military innovation that began in the shadow of Vietnam and ended with troops fighting through blinding sandstorms at night on the road to Baghdad. The multifaceted transformation strategy conceived in the 1970s paved the way for a military revolution in the 1990s and enabled unprecedented battlefield adaptation in the 2000s. After reviewing the revolutionary changes that led to American dominance in conventional warfare in the 1990s, the article examines US transformation policies in the 2000s to inform defense strategy and planning efforts in the 2010s.  相似文献   
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