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21.
We show the existence ofaverage cost (AC-) optimal policy for an inventory system withuncountable state space; in fact, the AC-optimal cost and an AC-optimal stationary policy areexplicitly computed. In order to do this, we use a variant of thevanishing discount factor approach, which have been intensively studied in recent years but the available results not cover the inventory problem we are interested in.The work of the first author (OVA) was partially supported by Fondo del Sistema de Investigación del Mar de Cortéz under grant SIMAC/94/CT-005. The work of the second author (RMdO) was partially supported by Consejo Nacional de Ciencia y Tecnologia (CONACyT) under grant 0635P-E9506.  相似文献   
22.
We study fundamental properties of monotone network enterprises which contain public vertices and have positive and negative costs on edges and vertices. Among the properties studied are the nonemptiness of the core, characterization of nonredundant core constraints, ease of computation of the core and the nucleolus, and cases of decomposition of the core and the nucleolus. Received December 1994/Final version March 1998  相似文献   
23.
A system such as missiles and spare parts of aircraft has to perform a normal operation in a severe environment at any time when it is used. However, the system is in storage for a long time from the delivery to the usage and its reliability goes down with time. Thus, a system in storage should be inspected and maintained at periodic times to hold a higher reliability than is prespecified.The following inspection model is considered: A system has three types of units, where unit 1 is maintained, unit 21 is not maintained but is replaced and unit 22 is neither maintained nor replaced. The system is overhauled if its reliability becomes lower than a prespecified probability. The number of replacements and time until overhaul are derived. Using these results, the average cost is obtained and both an optimal inspection time and an optimal replacement time to minimize it are numerically discussed.  相似文献   
24.
Abbas  SH 《应用数学和力学》1996,17(12):1077-1083
本文讨论了求解密集型线性方程组的两种并行算法。这两种算法都在下上单元(LU)分解。法的基础上使用了前向和后向置换进行的。这些算法在数值上是稳定的,并在顺序平衡机上用各种处理程序进行试验,都得到良好效果。  相似文献   
25.
We consider the spatially homogeneous Landau equation of kinetic theory, and provide a differential inequality for the Wasserstein distance with quadratic cost between two solutions. We deduce some well-posedness results. The main difficulty is that this equation presents a singularity for small relative velocities. Our uniqueness result is the first one in the important case of soft potentials. Furthermore, it is almost optimal for a class of moderately soft potentials, that is for a moderate singularity. Indeed, in such a case, our result applies for initial conditions with finite mass, energy, and entropy. For the other moderately soft potentials, we assume additionally some moment conditions on the initial data. For very soft potentials, we obtain only a local (in time) well-posedness result, under some integrability conditions. Our proof is probabilistic, and uses a stochastic version of the Landau equation, in the spirit of Tanaka [H. Tanaka, Probabilistic treatment of the Boltzmann equation of Maxwellian molecules, Z. Wahrsch. Verw. Geb. 46 (1) (1978-1979) 67-105].  相似文献   
26.
目标成本管理在机械加工行业的应用   总被引:1,自引:0,他引:1  
以机械加工行业为例,探讨了目标成本管理在企业管理工作中的应用  相似文献   
27.
在知识经济到来的今天,影响企业经营的环境不仅日益复杂,而且越来越不稳定,市场竞争更是日趋激烈.从财务管理角度探讨了供电企业如何开展开源节流、降本增效的经营活动.  相似文献   
28.
闫俐俐  张志成 《科技信息》2009,(23):368-368,362
本文着重对施工企业成本控制过程中的工程投标、成本预测、成本控制、成本核算这四个重要环节的成本管理进行了阐述、分析,提出了各环节的具体控制方法,以及明确相关部门成本控制责任,具有针对性,可供借鉴应用。  相似文献   
29.
    
In this research article, the objective of the work is to maximize the performance of solar pump based on input variables. The solar panel and motor pump set are the important parts of solar pump. The overall performance of the solar pump has been depending on the performance of solar panels and motor pump set. The tilt angle, surface azimuth angle, module temperature and speed of motor are most important input parameters on which whole performance of solar pump depends. So, for fulling these objectives a 5 hp (horsepower) solar pump has been installed in FET MJP Rohilkhand University, Bareilly located at 28.36° N, 79.43° E. The experimental data of output parameters at the different settings of input parameters and data generated by model equations have been optimized by the Response Surface Methodology (RSM) tool of Design of Experiments (DOE). The optimum setting of input parameters are Tilt Angle (TA) (36.22°), Surface Azimuth Angle (SA) (−1.26°), Module Temperature (MT), and speed of the motor (2169.69 RPM). On the optimum setting of input parameters, the values of the response are maximum Solar Flux (SF) (762 W/m2), maximum power output (3661.4578 W), minimum discharge (19.2681 m3/h), head developed (55.17 m), maximum motor efficiency (90.7488%), maximum exergetic efficiency (15.3799%), minimum Levelized cost of electricity (LCOE) (0.0361 $/KWh), maximum panel efficiency (17.1774%) and maximum overall efficiency (15.0117%).  相似文献   
30.
在变化减少方案理论的基础上,对变化性二因素和制造系统成本的关系进行了研究,运用灰色系统理论,建立了成本与变化性关系的灰色模型;并应用某纺织机械厂浆纱机产品的成本与变化性关系对部分模型进行了验证.  相似文献   
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