Performance analysis of the retrial queues with finite number of sources and service interruptions

This paper aims at presenting an analytic approach for investigating a single-server retrial queue with finite population of customers where the server is subject to interruptions. A free source may generate a primary call to request service. If the server is free upon arrival, the call starts to be served and the service times are independent, generally distributed random variables. During the service time the source cannot generate a new primary call. After service the source moves into the free state and can generate a new primary call. There is no waiting space in front of the server, and a call who finds the server unavailable upon arrival joins an orbit of unsatisfied customers. The server is subject to interruptions during the service processes. When the server is interrupted, the call being served just before server interruption goes to the retrial orbit and will retry its luck after a random amount of time until it finds the server available. The recovery times of the interrupted server are assumed to be generally distributed. Our analysis extends previous work on this topic and includes the analysis of the arriving customer’s distribution, the busy period, and the waiting time process.     

Semiparametric Smooth Coefficient Stochastic Frontier Model With Panel Data

ABSTRACT

We investigate the semiparametric smooth coefficient stochastic frontier model for panel data in which the distribution of the composite error term is assumed to be of known form but depends on some environmental variables. We propose multi-step estimators for the smooth coefficient functions as well as the parameters of the distribution of the composite error term and obtain their asymptotic properties. The Monte Carlo study demonstrates that the proposed estimators perform well in finite samples. We also consider an application and perform model specification test, construct confidence intervals, and estimate efficiency scores that depend on some environmental variables. The application uses a panel data on 451 large U.S. firms to explore the effects of computerization on productivity. Results show that two popular parametric models used in the stochastic frontier literature are likely to be misspecified. Compared with the parametric estimates, our semiparametric model shows a positive and larger overall effect of computer capital on the productivity. The efficiency levels, however, were not much different among the models. Supplementary materials for this article are available online.     

信息技术对未来农业发展的影响

信息网络技术的发展必将对现行农业产生冲击 ,未来农业的发展在全球一体化趋势的总目标下 ,自然资源、农业科学技术和农业劳动产品等都将更加遵从经济规律和比较优势的原则。文章从全球气候和土壤等自然资源的分布规律、区域地理经济特点及农业网络信息系统的功效出发 ,从农业生产、管理和贸易等方面论述信息技术对未来农业发展的影响 ,阐明了未来农业向生产有序化和农业高效化、管理系统化和决策信息化、技术高新化和商务电子化的方向发展的必然趋势     

试论新公共服务理论视野下的新疆乌昌一体化

新公共服务理论认为,政府应提供服务,而不是掌舵,政府越来越重要的职能是帮助公民明确表达和满足他们的共同利益需求。目前新疆乌昌一体化的发展,强调了区域经济发展在区域一体化中的中心角色,从新公共服务理念的角度来看,有效治理区域发展中诸多公共性问题有一定难度。为进一步提升乌昌一体化的质量,该区域应适时改进已有的区域发展策略。     

关于社会秩序存在的前提性心思考

力求在社会哲学的层面上从社会秩序的生成、总体性展开以及秩序主体构成等几个视角对社会秩序存在的实践基础进行分析,以推进社会秩序问题的相关研究.指出在社会哲学的意义上,社会秩序有其存在的实践基础.实践是探寻社会秩序的存在本质的现实起点.社会秩序是在实践中生成,并在实践的基础上总体性展开.要正确地认识社会秩序的存在方式,就必须把社会秩序放到其与人的关系中去探讨,而要正确把握社会秩序与人在实践中的关系,必须首先正确地理解社会秩序的主体问题.     

青海地区蒙古族服饰述略

本文从蒙古族进入青海的不同历史阶段,简略的叙述了青海蒙古族服饰文化形成的历史脉络及形成后随着地域、自身的发展和周边民族的不同而又形成独特的服饰文化。     

清朝用兵驻兵西藏制度的形成、发展和影响

清代用兵西藏是清治藏方略的重要内容,驻兵是用兵之后清政府在西藏进一步开展政治、军事工作的继续与发展。文章宏观地分析和研究了这一重要历史进程及其特点和影响,认为清代用兵驻兵西藏是清政府管理西藏地方过程中形成的一项制度,直接体现了清朝对西藏行使主权的力度和层面,其意义深远。它保卫了边疆、巩固了国防、安定了西藏、推动了西藏地方对中央政府的向心力,促进了西藏地方政治、军事、经济和文化的积极发展,为维护祖国统一和民族团结作出了重要贡献。     

邓小平解决民族问题的方法论研究

本文从邓小平解决民族问题的理论入手 ,研究了邓小平解决民族问题的方法论 ,研究表明 ,只有解放思想、实事求是 ,才能够很好地解决民族问题     

吐谷浑的宗法统治

吐谷浑经历着游牧民族一般具有的氏族血缘组织与初期国家行政、军事组织紧密结合的“三位一体”的宗法奴隶制社会 ,并在中原王朝及汉文化的影响下逐步向封建制社会过渡。