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91.
This paper provides a framework in which warranty policies for non-repairable items can be evaluated according to risk preferences of both buyers and sellers. In particular, a warranty price schedule is established such that sellers are indifferent among the policies. Given this schedule, a buyer's response is expressed by selecting the price-warranty combination that minimizes disutility. Within this framework, a warranty can be viewed as an instrumet of risk management that can induce more sales and greater profitability. For given utility functions, analytical results for the development of a price schedule are developed. Numerical results illustrate the substitution effects between warranty terms, prices, and risk parameters. 相似文献
92.
Lakshman S. Thakur 《海军后勤学研究》1986,33(2):325-358
We implement a solution procedure for general convex separable programs where a series of relatively small piecewise linear programs are solved as opposed to a single large one, and where, based on bound calculations developed in [13] and [14], the ranges of linearization are systematically reduced for successive programs. The procedure inherits ε-convergence to the global optimum in a finite number of steps, but perhaps its most distinct feature is the rigorous way in which ranges containing an optimal solution are reduced from iteration to iteration. This paper describes the procedure, called successive approximation, discusses its convergence, tightness of the bounds, bound-calculation overhead, and its robustness. It presents a computer implementation to demonstrate its effectiveness for general problems and compares it (1) with the more standard separable programming approach and (2) with one of the recent augmented Lagrangian methods [10] included in a comprehensive study of nonlinear programming codes [12]. It seems clear from over 130 cases resulting from 80 distinct problems studied here that significant savings in terms of computational effort can be realized by a judicious use of the procedure, and the ease with which it can be used is appreciably increased by the robustness it shows. Moreover, for most of these problems, the advantage increases as the size, nonlinearity, and the degree of desired accuracy increase. Other important benefits include significantly smaller storage requirements, the ability to estimate the error in the current solution, and to terminate the algorithm as soon as the acceptable level of accuracy has been achieved. Problems requiring up to about 10,000 nonzero elements in their specification and about 45,000 nonzero elements in the generated separable programs resulting from up to 70 original nonlinear variables and 70 nonlinear constraints are included in the computations. 相似文献
93.
In many decision-making situations, each activity that can be undertaken may have associated with it both a fixed and a variable cost. Recently, we have encountered serveral practical problems in which the fixed cost of undertaking an activity depends upon which other activities are also undertaken. To our knowledge, no existing optimization model can accomodate such a fixed cost structure. To do so, we have therefore developed a new model called the interactive fixed charge linear programming problem (IFCLP). In this paper we present and motivate problem (IFCLP), study some of its characteristics, and present a finite branch and bound algorithm for solving it. We also discuss the main properties of this algorithm. 相似文献
94.
95.
在分析目前射击精度的理论和影响射击精度因素的基础上,对命中率计算公式中的散布圆半径进行修正,修正后的参数考虑了人对精度的影响。根据实弹射击结果,具体验证了修正后的公式。 相似文献
96.
分析研究了测量火炸药静电起爆最小发火能量的三种方法,并进行了大量的对比试验,提出了首先进行OSTR法试验,然后进行逐步降压法试验,从而得出火炸药静电起爆的最小发火能量。 相似文献
97.
作者在前面的文章中报导了扭轮摩擦传动能实现亚纳米级的定位分辨率。然而,这套装置在结构上的复杂之处就是在于采用了静压轴承支撑扭轮。本文指出了扭轮摩擦传动在结构上如何可以简化为采用球轴承支撑扭轮。在简化之后,实验表明定位分辨率小于1纳米。本文得出结论,采用球轴承的扭轮摩擦传动对于在洁净环境下要求实现纳米级定位的制造过程变得更为方便,而且可以取代滚珠丝杠以及常规摩擦传动方式。 相似文献
98.
文中建立了电子战条件下雷达信号环境数学模型,包括雷达发射信号数学模型,目标回波信号数学模型,电子干扰(有源干扰和无源干扰)信号数学模型,杂波数学模型以及噪声数学模型 相似文献
99.
Properties of a finite-range failure-time distribution, that includes the exponential as a particular case, have been studied. The distribution is IFR when the shape parameter exceeds unity, but is IFRA always. For a given value of the shape parameter, the distribution is NBUE over a segment of its range. Estimators of parameters have been derived. Distributions of two-component series, parallel, and standby system lives have also been worked out. 相似文献
100.
In this article we study the estimation of the average excess life θ in a two-parameter exponential distribution with a known linear relationship between α (the minimum life) and θ of the form α = aθ, where a is known and positive. A comparison of the efficiencies of estimators which are linear combinations of the smallest sample value and the sample sum of deviations from the smallest sample value and the maximum likelihood estimators is made for various sample sizes and different values of a. It is shown that these estimators are dominated in the risk by the minimum-risk scale equivariant estimator based on sufficient statistics. A class of Bayes estimators for inverted gamma priors is constructed and shown to include a minimum-risk scale equivariant estimator in it. All the members of this class can be computed easily. 相似文献