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71.
张海青 《电脑编程技巧与维护》2010,(10):33-34
人才已成为企业自身战略目标的一个非常关键的因素。"公平、公正、合理"的企业管理理念和管理水平的提高,使社会对人事管理有了更高的需求。同时,由于数据库技术、客户/服务器技术,特别是Web技术的发展,使得新一代人事信息管理系统的出现成为必然。 相似文献
72.
本文针对现有企业文档管理中存在的问题和需求,设计了一种基于网络的、分布式的文档在线管理方案。以微软新产品SharePoint Server 2007为该解决方案的设计平台,研究了SharePoint Server 2007为文档管理提供的几个重要的功能并在此基础上设计了一个实际的案例。 相似文献
73.
74.
程光德 《计算机光盘软件与应用》2010,(4):107-107
该系统基于校园网,采用ASP.NET+SQL Server开发技术,解决了传统人工方式处理学生成绩信息的弊端,实现了学校人力资源的优化和学生成绩信息的科学管理,具有较高的实用价值。 相似文献
75.
In this paper, we consider a discrete-time queuing system with head-of-line non-preemptive priority scheduling and a single server subjected to server interruptions. We model the server interruptions by a correlated Markovian on/off process with geometrically distributed on and off periods. Two classes of traffic are considered, namely high-priority and low-priority traffic. In the first part of the paper, we derive an expression for the functional equation describing the transient evolution of this priority queuing system. This functional equation is then manipulated and transformed into a mathematical tractable form. This allows us to derive the joint probability generating function (pgf) of the system contents. From this pgf, closed-form expressions for various performance measures, such as mean and variance of system contents and customer delay can be derived. Finally, we illustrate our solution technique with some numerical examples, whereby we demonstrate the negative effect of correlation in the interruption process on the performance of both classes. Some numerical results illustrating the impact of second-order characteristics of the arrival process on mean delays are also presented. The proposed approach which is purely based on pgfs is entirely analytical and enables the derivation of not only steady-state but transient performance measures, as well. The paper presents new insights into the performance analysis of discrete-time queues with service interruption and it also covers some previously published results as a special case.
Scope and purpose
In this contribution, we consider a practical queuing model, with HOL priority scheduling, two classes of traffic, and a server which is subjected to a correlated Markovian interruption process. We first derive a non-linear functional equation relating the joint pgf of the system state vector between two consecutive slots. Then we outline a solution technique to solve for this functional equation. This allows us to derive the joint pgf of the system contents of both classes, from which various performance measures related to mean system contents and customer delays are derived. We also demonstrate how the proposed approach allows for derivation of transient performance measures, as well. It should be noted that detailed coverage of the transient analysis of the system is beyond the scope of this paper.To our best knowledge, this is the first initiative that aims to explore the performance of queuing systems with priority scheduling when the shared server is subjected to service interruption. The paper also generalizes the results of Walraevens et al. (Analysis of a single-server ATM queue with priority scheduling, Computers & Operations Research 2003;30(12):1807–30) by incorporating service interruption into their original queuing model. By means of numerical results, the paper also demonstrates the effect of correlation in the service interruption process on the performance of both classes of customers. The impact of second-order characteristics of the arrival process on mean delays is also investigated. 相似文献76.
Quantitative performance modeling of complex information systems is of immense importance for designing enterprise e-business infrastructures and applications. In this paper, we present a traffic model of a server node in a typical transaction processing middleware system as well as a quantitative framework to model and analyze its performance. A multi-class open queueing network model is presented in which multi-class jobs are admitted to a number of server processes sharing hardware resources including the CPU and the disk. We have developed a viable approximation method, which decomposes the dependent components into their independent counterparts while preserving their relevant characteristics. We have conducted queueing-theoretic delay analyses and verified the approach using simulation. Results demonstrate the strength of our approach in predicting delays, elapsed times and other system performance measures. 相似文献
77.
介绍使用数据挖掘工具SQL Server 2005 Data Mining、SPSS/Clementine进行仓库物资补给预测的方法和步骤并就使用两种教据挖掘工具,利用不同的挖掘算法进行物资补给预测的结果进行比对分析,以便使库存数量和成本之间取得平衡。 相似文献
78.
XML(Extensible Markup Language)即可扩展标记语言的数据特性使其与数据库的关系日益密切。研究了SQL Server2000数据库对XML的支持,分析了采用HTTP(Hypertext Transfer Protocol)即超文本传输协议方式访问SQL Server的原理.描述了IIS(Internet Information Server)即互联网信息服务的详细配置过程,用几种方式实现了HTTP方式访问SQL Server数据库,并返回XML文件。最后结合具体的实例阐明了上述几种方法的实现. 相似文献
79.
基于Windows Server2008设计并实现了支持IPV4和IPV6协议的FTP服务器。对IPV4环境中的应用程序向IPV6迁移进行了实质性的探索和研究。该文是使用Windows Server2008 IIS70搭建FTP服务器,并用SmartFTP实现访问。 相似文献
80.
曾海峰 《数字社区&智能家居》2009,(8)
SQL Server 2000是当今深受欢迎的关系数据库管理系统,是一个杰出的数据库平台。结合高职院校的办学目的以及SQLServer 2000课程特色,针对性地提出了模块化与案例驱动相结合的教学方法,对其进行了详细的分析与举例,有着积极的现实意义。 相似文献