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101.
102.
In this paper, we study the maintenance policy following the expiration of the non‐renewing replacement–repair warranty (NRRW). For such purposes, we first define the non‐renewing free replacement–repair warranty and the non‐renewing pro rata replacement–repair warranty. Then the maintenance model following the expiration of the NRRW is discussed from the user's point of view. As the criterion to determine the optimal maintenance strategy, we formulate the expected cost rate per unit time from the user's perspective. All system maintenance costs incurred after the warranty is expired are paid by the user. Given the cost structures during the life cycle of the system, we determine the optimal maintenance period following the expiration of the NRRW. Finally, a few numerical examples are given for illustrative purposes. Copyright © 2012 John Wiley & Sons, Ltd. 相似文献
103.
郭先平 《应用数学学报(英文版)》2000,16(2):205-212
1.IntroductionandModelTheearlierliteratureaboutconstrainedMarkovdecisionprocesses(MDPs,forshort)canbefoundinDerman'sbook[1].Later,therehavebeenmanyachievementsinthisarea.Forexample,averagerewardMDPswithaconstrainthasbeendiscussedbyBeutleandRosslz],HordijkandKallenberg[3]jAltmanandSchwartz[4],etal.Inthecaseoffinitestatespace,discountedrewardcriterionMDPswithaconstrainthasbeentreatedbyKallenberg['landTanaka[6],etal.Whenstatespaceisdenumerable,suchproblemswerediscussedbySennott[71andAlt… 相似文献
104.
We investigate an initial value problem which is closely related to the Williams-Bjerknes tumour model for a cancer which
spreads through an epithelial basal layer modeled onI ⊂ Z
2. The solution of this problem is a familyp = (p
i(t)), where eachp
i(t)could be considered as an approximation to the probability that the cell situated ati is cancerous at timet. We prove that this problem has a unique solution, it is defined on [0, +∞[, and, for some relevant situations, limt→∞
P
i(t) = 1 for alli ∈ I. Moreover, we study the expected number of cancerous cells at timet. 相似文献
105.
离散时间模型下的罚金折现期望 总被引:1,自引:0,他引:1
本文研究完全离散风险模型下的罚金折现期望.我们首先得到Φ(u,w)的瑕疵离散更新方程,利用控制收敛定理得出Φ(0,w)的显式解;然后通过对w的讨论,分别推出f(0;x),g(0;y)与ψ(0)的显式解。 相似文献
106.
This paper concerns nonstationary continuous-time Markov control processes on Polish spaces, with the infinite-horizon discounted cost criterion. Necessary and sufficient conditions are given for a control policy to be optimal and asymptotically optimal. In addition, under suitable hypotheses, it is shown that the successive approximation procedure converges in the sense that the sequence of finite-horizon optimal cost functions and the corresponding optimal control policies both converge. 相似文献
107.
本文研究了一类索赔过程与索赔额大小相关的风险模型.利用无穷小方法,得到了该相依模型的折扣惩罚函数的期望满足的方程.及其拉普拉斯变换的表达式.并且给出指数索赔时的具体运用. 相似文献
108.
Stochastic integer programs are notoriously difficult. Very few properties are known and solution algorithms are very scarce. In this paper, we introduce the class of stochastic programs with simple integer recourse, a natural extension of the simple recourse case extensively studied in stochastic continuous programs.Analytical as well as computational properties of the expected recourse function of simple integer recourse problems are studied. This includes sharp bounds on this function and the study of the convex hull. Finally, a finite termination algorithm is obtained that solves two classes of stochastic simple integer recourse problems.Supported by the National Operations Research Network in the Netherlands (LNMB). 相似文献
109.
市场潜能、预期收入与跨省人口流动——基于空间计量模型的分析 总被引:1,自引:0,他引:1
综合新经济地理学模型与迁移效应函数,本文构建了包含市场潜能和预期收入的人口迁移理论模型,并采用空间计量模型及其稳健性检验进行了中国数据的实证分析。研究结果表明:市场潜能和预期收入及其空间溢出效应对人口迁入有显著的促进作用,但是两者对人口迁移的作用路径不同,市场潜能仅对本地区有直接正向作用,对相邻地区的空间溢出效应不明显,相邻地区则对本地区的人口迁移存在负向反馈效应;而预期收入对本身以及相邻地区的影响为正向,相邻地区的预期收入反馈效应也为正;地区的人口密度和消费水平则对人口迁移有显著的负向作用。 相似文献
110.
The allocation of cost savings is very important for the success of the joint relationship between the buyer and vendor in supply chain management. This paper develops integrated models with permissible delay in payments for determining the optimal replenishment time interval and replenishment frequency. In addition, the variant pricing strategy is employed to obtain both sides’ cost savings in order to entice buyers to join long-term cooperative relationships. A simple solution algorithm is presented to allocate the cost savings in the integration model, and a numerical example is used to demonstrate the feasibility of the proposed integration models. 相似文献