Optimization problems for consecutive-2-out-of-n:G system

Abstract

This paper considers the optimization problems for a consecutive-2-out-of-n:G system where n is considered to be fixed or random. When the number of components is constant, the optimal number of components and the optimal replacement time are discussed by minimizing the expected cost rates. Furthermore, we focus on the above discussions again when n is a random variable. We give an approximate value of MTTF and propose the preventive replacement policy, respectively.     

Analysis of a two incongruent arrivals and services M/G/1 queue with random feedback

A queuing system with two incongruent arrivals and services is considered. Two kinds of customers enter the system by Poisson process and the service times are assumed to have general distribution. After first kind service completion, it may feedback to repeat the first service, leave the system or go to give second service. The same policy is applied for the other kind of customer. All stochastic processes involved in this system are independent. We derive the probability generating function for each kind and for the system that yield the performance measures. Some numerical approaches examined the validity of the results.     

深度阅读视域下幼儿园故事剧课程活动实施策略——以中班故事剧《今天运气怎么这么好》为例

摘 要:借鉴深度阅读理念，以故事剧《今天运气怎么这么好》为例，将实施深度阅读的“三个流程、三个关键词、两种能力”融合于故事剧课程活动的建构，改变传统故事学习、故事表演中重形式轻实质、重表面轻内在的弊端。整个过程凸显幼儿与故事、与环境、与成人的充分互动，重视教师的支持作用，让教师成为指导幼儿深度阅读活动的关键因素，陪伴幼儿深度卷入阅读世界，共同留下精彩足迹。     

保温层的临界热绝缘直径

通过对传热速率随保温层直径增加而变化的讨论,得出结论,保温层直径必须大于保温层的临界热绝缘直径,才能降低热损失。     

A panel study of migration,self-selection and household real income

The impact of migration on income for Swedish multi-adult households is examined using panel data pertaining to a sample of stable household constellations during the period 1980–1990. In contrast to previous studies, data on household disposable income is employed in estimating the income function. The empirical results indicate no significant effect on real disposable income from migration. In addition, the hypothesis of no self-selection, or zero correlation between the errors in the decision function and the income function, cannot be rejected. Received: 10 May 1995 / Accepted: 14 August 1996     

浸乎世风 染乎世情——全真教与元杂剧关系谈

本文从道家思想与全真教的关系切入,对元杂剧中关涉全真教的剧目进行了剖析,并据以历史事实指出： 元杂剧中的氤氲道气是全真教对元代社会巨大影响这一世风世情浸染的结果。尤其值得注意的是元杂剧中存在着终极意义层面上的审美超越倾向     

一种适用于NGSO MSS网络的混合信道分配方案

针对ＮＧＳＯＭＳＳ网络的动态特性,提出了一种适用于该网络的混合信道分配方案。在该方案中,固定信道采用非均匀压缩图案分配算法分配给各小区作为标称信道专用,并定期根据变化了的业务条件进行重新分配,动态信道的指派采用最先可行ＦＡ（ＦｉｒｓｔＡｖａｉｌａｂｌｅ）算法。仿真结果表明,在较宽的负载范围内,运用该方案比固定信道分配方案均有更好的性能,并能有效地降低切换呼叫和信道更新期间的呼损率,从而显著提高网络的业务承载量。     

两类含两个变态贝塞尔函数积的积分公式

从变态贝塞尔方程出发,构造了它的一个变换形式,利用微积分学中的定理,巧妙地求得了含两个变态贝塞尔函数和的积的一个普遍的积分公式。进而利用变态贝塞尔函数的性质,可简洁地推导出电磁场领域中两类非常重要的积分的解析表达式,在处理圆柱结构下有关电磁场能量或电磁波传输功率的计算问题时,具有普遍的应用价值。     

北宋名相韩琦在定州

韩琦是北宋著名的政治家,历仕仁宗、英宗、神宗三朝,功绩卓著,对北宋政局产生了较大的影响。他在边陲重镇定州为帅的五年中,整顿军队,增强国防,为政爱民,造福一方,深得百姓的拥戴,显现出他忧国忧民的士大夫情怀。