Capacity Planning and Allocation for Web‐Based Applications

Motivated by the technology division of a financial services firm, we study the problem of capacity planning and allocation for Web‐based applications. The steady growth in Web traffic has affected the quality of service (QoS) as measured by response time (RT), for numerous e‐businesses. In addition, the lack of understanding of system interactions and availability of proper planning tools has impeded effective capacity management. Managers typically make decisions to add server capacity on an ad hoc basis when systems reach critical response levels. Very often this turns out to be too late and results in extremely long response times and the system crashes. We present an analytical model to understand system interactions with the goal of making better server capacity decisions based on the results. The model studies the relationships and important interactions between the various components of a Web‐based application using a continuous time Markov chain embedded in a queuing network as the basic framework. We use several structured aggregation schemes to appropriately represent a complex system, and demonstrate how the model can be used to quickly predict system performance, which facilitates effective capacity allocation decision making. Using simulation as a benchmark, we show that our model produces results within 5% accuracy at a fraction of the time of simulation, even at high traffic intensities. This knowledge helps managers quickly analyze the performance of the system and better plan server capacity to maintain desirable levels of QoS. We also demonstrate how to utilize a combination of dedicated and shared resources to achieve QoS using fewer servers.     

Colleges and universities’ use of the World Wide Web: A public relations tool for the digital age

This study explores college and university Web sites to determine the extent institutions utilize the Web to accomplish public relations goals. A sample of the 129 best national universities in the United States compiled by the US News and World Report was used for analysis. Results show that schools with a small-medium level of student recruitment and alumni giving are more likely to actively utilize the Web. In this light, schools behind in school excellence strive to use the Web as an important public relations tool to overcome their inferiority to superior schools.     

基于Web系统工程应用的开发

基于Web的系统与传统的软件既有相同之处,也有不同的地方。一般都采用传统的软件工程方法进行,这样使得系统开发效率低,系统性能差。本文就基于Web的系统的分析、开发、测试、安全性和可用性进行探讨。     

QoS支持下的GIS服务链最优化问题研究

针对当前OGC互操作标准未提供QoS支持的现状,对OGC服务标准进行了服务质量扩展。在此基础上实现了一种基于遗传算法、具有全局QoS约束的最优化服务选择方法。该方法采用了树型染色体编码方式及基于罚函数法的适应度函数。通过与整数规划得到的最优解进行对比,验证了该方法解质量的有效性,并通过改变候选服务数和任务数等试验条件,证明了该方法的时间复杂度近似线性。     

数据仓库技术及其在Web上动态报表中的应用

介绍了数据仓库技术,结合实际项目阐述了构建数据仓库及利用PivotTable组件来创建功能强大的基于Web的数据分析系统。用户可以在Web浏览器中对数据进行统计、过滤和重组,即实现一般的数据挖掘功能。系统后台由Microsoft OLAP(Online Analytical Processing)Servers支持,前台采用ASP（Active Server Page)实现,该系统在网页上可实现方便灵活的动态报表。     

1900～2010年现代化研究的文献计量学分析

本文对1900-2010年期间现代化研究的外文和中文相关文章和图书进行了统计分析,分析变量包括文章和图书的数量分布、增长率、文章类型、作者分布、学科分布、国家分布、期刊分布和被引频次等,揭示了现代化研究的发展趋势和时空分布.20世纪60年代以来.现代化研究文献开始增长,21世纪前10年现代化研究出现高潮.     

向量服务格支持下的Web服务检索

将概念格理论与Web服务特征相结合,提出了一种新型的服务组织结构——向量服务格,并利用向量服务格中得到的方法向量概念对方法向量进行扩展.在这个扩展的方法向量基础上,提出了服务检索方法,给出了方法向量、方法向量背景和k-维方法向量概念等的定义.实验结果表明,基于向量服务格的服务检索具有较高的检索效率.     

地理信息系统发展趋势及展望

介绍了地理信息系统（GIS）的发展趋势,包括从单机模式向网络模式GIS、从二维向三维甚至高维、从封闭系统到开放系统、从1S到3S甚至多S集成,最终是虚拟现实到数字地球,展望了未来GIS网络化、社会化、全球化、大众化的发展方向。     

医学讲授型多媒体网络课程的设计与开发

随着校园网在高校教育中的深入,讲授型多媒体网络课程在医学教育中发挥着越来越大的作用,本文从实践中总结了医学讲授型多媒体网络课程系统的结构及其核心授课录像的设计与制作。     

基于Web的网上测试系统的设计与实现

研制了一个基于Web的网上测试系统 ,阐述了系统的工作原理、关键技术以及系统的数据库、界面的设计 ,并讨论了系统的安全性 .本系统具有很好的可扩充性 ,实用性 .