A two phases queueing system with Bernoulli vacation schedule under multiple vacation policy

This paper deals with a single server Poisson arrival queue with two phases of heterogeneous service along with a Bernoulli schedule vacation model, where after two successive phases service the server either goes for a vacation with probability p (0≤p≤1) or may continue to serve the next unit, if any, with probability q(=1−p). Further the concept of multiple vacation policy is also introduced here. We obtained the queue size distributions at a departure epoch and at a random epoch, Laplace Stieltjes Transform of the waiting time distribution and busy period distribution along with some mean performance measures. Finally we discuss some statistical inference related issues.     

A gender comparison of HIV and drug use across the rural-urban continuum

Despite the central role of women drug users in escalating AIDS statistics, there is still a limited number of studies that examine the roles of gender and drug use type in HIV seroprevalence. This lacuna in the research literature has led to significant gaps in researchers' understanding of how and to what extent women may differ in their drug-using and HIV risk behaviors compared to their better-studied male counterparts. This study, derived from a sample of 3,555 out-of-treatment drug users residing in three South Florida urban and rural communities, attempts to compare the drug usage and needle and sexual risk behaviors of male and female drug users that put them at risk for HIV infection. The overall seropositivity rate for women drug users was 26.5% compared to 19.5% for their male counterparts. Results of multivariate analyses indicate that females compared to males were 1.4 times more likely to be HIV seropositive. Risk behaviors associated with this elevated seropositivity include living arrangements, homeless status, drug use, sexual trading behaviors, and history of STDs. Furthermore, there was a strong linear relationship between drug use type and HIV seroprevalence among women drug users. Compared to those who were neither crack smokers nor injectors of illicit drugs, those who were crack smokers only were 2 times more likely to be HIV seropositive, while those who were both crack smokers and injectors were 5 times more likely to be HIV seropositive, and those who were injectors only were 6 times more likely to be HIV seropositive. These findings indicate that among women, drug abuse and its associated risk behaviors, increase the vulnerability of this population for HIV and thus render them an extremely important priority population on which to focus HIV prevention and public health efforts and programs.     

汉语时间概念隐喻的认知分析

隐喻不仅是一种语言现象,更是一种思维现象。人类通过其他具体概念来认知时间这一抽象概念。认知过程中,汉民族通过多种意象图式对时间概念进行建构。汉语中的时间概念隐喻分为时间是空间;时间是实体;时间是金钱。形成方位隐喻、实体隐喻、结构隐喻三种隐喻方式。汉语时间概念隐喻在人类语言尤其是在日常语言中占有重要地位。     

英汉词义的对比及翻译方法探究

语言翻译的过程不仅是简单的语言转换,更是两种思维方式和观念系统的相互作用及深化的过程。本文通过英汉词汇意义的构成、词义差别的对比,分析了两种语言之间产生差异的原因,并介绍了常见的翻译方法。     

电子商务环境下产品评论特征对消费者信息采纳影响机理的探索

目的/意义基于信息采纳模型和信息系统成功模型,探索了在线产品评论特征对影响消费者信息采纳决策的影响机理。设计/方法通过实验收集数据和偏最小二乘法结构方程（PLS-SEM）来分析数据并验证假设。结论/发现有用度投票对在线产品评论诊断性有正向影响,结构化格式对易用性有正向影响,易用性对在线产品评论诊断性有正向影响,易用性和诊断性对在线产品评论采纳决策存在着正向影响,但认知需求作为调节变量对有用度投票和诊断性的关系及易用性和诊断性的关系影响不显著。     

利用异文从事汉语史研究应注意的三个问题

文献异文情况复杂，运用起来应特别审慎。利用异文从事汉语史研究应注意分辨异文的性质、真实性、来源这三个问题。出于不同原因形成的异文，其性质也有差异，可以分为校勘性异文、用字性异文和修辞性异文三类。校勘性异文应运用文献整理的方法和原则判别正误，用字性异文应主要运用文字学的理论和方法确定字际关系，修辞性异文应运用语言学（汉语史）的理论和方法探寻词与词、句与句之间的变化关系。利用异文时还必须注意异文项的真实性，从而保证作为论据的有效性。利用修辞性异文进行语言比较，必须确认异文的真实来源，只有建立真正的异文对应关系，才能进行有效的对比，避免无的放矢之弊。     

清代谥法制度的来源与确立

清代谥法制度是继承历史上确立并在历史各个朝代发展中不断变化的谥法制度,文章探讨了谥法制度是如何产生和发展,如何被清代继承和改变,其内容在使用的过程中发生了怎样的变化,出现了怎样的特点.     

城市土地集约利用研究的问题与困境

基于德国"农业经营学"研究中土地集约概念的梳理,以土地投入产出的结构性解析为切入点,比较了城市与农业土地利用的区别.文章指出,从农业土地集约拓展到城市土地集约利用,造成"集约"这一概念两个不同质的内涵与理解,这有违于科学术语一致性原则.文章对集约目标泛化造成研究中和政策实施上的困境进行了分析,提出了需要进一步研究的问题.     

网络体育信息资源的特征及利用

网络体育信息资源的有效利用,能促进体育教育、科研和训练水平的提高与发展。本文阐述了网络体育信息资源的含义和特征,分析了体育信息资源利用的5个阶段以及5个层面,并对加强体育信息资源的整合、开发和利用,提出了合理化建议。     

论《管子·水地》篇水本原思想与古希腊水本原思想的区别

《管子·水地》篇提出了＂水是万物的本原和生命之源＂的观点,又把水道德化,主张以水施行教化。古希腊哲学家泰勒斯也有＂水是万物本原＂的主张,认为一切事物都是由水产出来的。两种水本原哲学思想在不同的时代以及不同的地区产生,它们之间有相同的地方,但更多的却是结合各自时代与地理因素而形成的不同之处。