Optimal scheduling replacement policies for a system with multiple random works

From the economical viewpoint in reliability theory, this paper addresses a scheduling replacement problem for a single operating system which works at random times for multiple jobs. The system is subject to stochastic failure which results the imperfect maintenance activity based on some random failure mechanism: minimal repair due to type-I (repairable) failure, or corrective replacement due to type-II (non-repairable) failure. Three scheduling models for the system with multiple jobs are considered: a single work, N tandem works, and N parallel works. To control the deterioration process, the preventive replacement is planned to undergo at a scheduling time T or the job's completion time of for each model. The objective is to determine the optimal scheduling parameters (T^* or N^*) that minimizes the mean cost rate function in a finite time horizon for each model. A numerical example is provided to illustrate the proposed analytical model. Because the framework and analysis are general, the proposed models extend several existing results.     

社会转型与观念变迁--以“道德缺失”为中心的考察

尽管“道德缺失”是转型期中国一个不容忽视的社会问题，但当代的“道德缺失”现象并非严重到了危机阶段，中国古代也不是“道德天堂”。今天的道德困境可以归因于社会环境的巨大变化。这种问题的解决，需依靠有效的维护机制作为保障。落实到根本，还是要大力发展经济，建设市民社会。     

阅读与语篇理解的相关理论分析

阅读是外语教学和学习中的重要环节。阅读不仅是读者知识积累和经验积淀的反映,而且可以构架起作者和读者之间沟通的桥梁。掌握了语篇生成的理论基础和技巧,读者就能在阅读中驾轻就熟地理解作者的意图和观点,从而达到理解语篇的目的。     

广播广告的话语结构成分及其组合模式

从播出方式和广告文稿的结构成分看 ,播音广告文稿的话语结构安排 ,主要有三种播出形式 :一人单播式 ,二人对播式 ,多人演播式。广播广告文稿的话语结构成分有二 :广告文稿主体 ,广告主题宣讲 ,两者进行多种有效组合。其中广告文稿主体部分的人物角色有多种转换形式和多种组合形式 ,由此构成富有鲜明个性和创意的播音广告文稿的结构     

话题转换的顺应性研究

根据顺应理论,使用语言的过程是一个进行选择的过程,语言使用者不仅选择语言形式,同时还选择使用策略。话题转换现象是对社会规约和心理世界的一种顺应。话题转换不当,会产生负面影响,妨碍交际的进行。     

毛泽东反封建思想论纲

毛泽东的反封建思想是毛泽东思想的重要组成部分 ,它由革命主题论、反封建核心论、反封建根本问题论及文化革命论等内容组成。毛泽东的反封建思想是中国民主革命及新中国前 2 8年反封建斗争实践的指导思想。但是 ,我们还应该看到 ,毛泽东的反封建思想并没有形成一个独立发展的完整思想体系 ,他长于对物质制度层面封建主义的批判 ,而对思想意识层面封建主义的批判则严重不足。这构成了整个毛泽东思想科学体系的严重不足。     

新形势下高校学报编辑需强化的意识与能力

高校学报能否在激烈的市场竞争中不断拓展生存与发展空间，保持良好发展势头，在很大程度上取决于学报编辑的意识和能力。高校学报编辑只有不断强化品牌意识、读者意识、作者意识和规范意识，不断强化选题策划能力、公关能力、外语能力和科研能力，才能适应新形势，应对新挑战。     

多校区图书馆的典藏工作

高校合并后,许多院校的图书馆都出现了多校区、多分馆的管理局面。笔者从新图书典藏、调拨、剔除几个方面简要论述了如何搞好多校区图书馆的典藏工作。     

Some remarks on the physical models concerning two different approaches to inference in statistical process control

Summary For technological applications it can be useful to identify some simple physical mechanisms, which, on the basis of the available knowledge of the production process, may suggest the most appropriate approach to statistical control of the random quantities of interest. For this purpose the notion of rupture point is introduced firstly. A rupture point is characterized bym randomly arising out of control states, assumed to be mutually exclusive and stochastically independent. Shewhart's control charts seem to represent the natural statistical tool for controlling a rupture point; however it is shown that they are fully justified only when the hazard rates attached to the causes of failure are constant. Otherwise, typically in the presence of time increasing hazard rates, Shewhart's control charts should be completed by a preventive intervention rule (preventive maintenance). In the second place, the notion of dynamic instability point is introduced, which is specifically characterized by assuming that the random quantity of interest is ruled by a stochastic differential equation with constant coefficients. By discretization, developed according to a possibly new approach, it is shown that the former model reduces to an equation error model, which is among the simplest used in adaptive control, and thus particularly easy to deal with in regard to parameter estimation and the definition of the optimum control rule.     

科技特派员制度生命力的探析

地处闽北的南平市在发展当地经济、促进农业重大转型的特定时期,启动科技特派员制度,有其深刻的时代背景和现实意义。本文从科技特派员制度创举与活力切入,分析这一制度创举深层次的原因,并进一步探讨这一制度生命力如何在新时期持续和创新。