The Distribution of the Maximum Sum of Rank

In this paper a c-sample slippage analogue of the Wilcoxon [11] test is considered. Given a sample of size n for each of c populations, the test rejects the hypothesis that the c populations are identical when max_1≤i≤c σ _k r _ik > λ, where r _i1, …, r _in are the ranks of the observations from the i-th population in the combined sample of size cn. The small and large sample distributions of the test statistic are derived. Tables of the exact distribution are given for c = 2(1)5, n = 2(1)5. Tables of critical values are given for c = 2(1)6, n = 2(1)8 for values of α = 0.001, 0.005, 0.01, 0.025, 0.05, 0.10, and 0.20.     

Hierarchical entity-relationship diagrams: the model,method of creation and experimental evaluation

A bottom-up method for creating a hierarchy of entity-relationship diagrams (HERD) from a given, flat ER diagram (ERD) is proposed. The hierarchy consists of simple and interrelated diagrams—ER structures—with external relationships to other structures. The HERD-tree diagram, which provides the most general view of the conceptual schema, is located at the top of the hierarchy. The method is based on packaging operations, which group entities and relationships according to certain criteria. These operations are applied in several steps on a given (presumably large-scale) ERD. We describe the new constructs, which are added to the ER model to enable the creation of HERD, and a bottom-up method for creating HERD. We also evaluate HERD from the point of view of user comprehension and preference, based on an experimental comparison to flat ERDs.

The Migration of Multi-tier E-commerce Applications to an Enterprise Java Environment

As technology evolves, many organizations face the problem of migrating legacy applications from one technology base to another. We report on a case study involving the migration of legacy code into the IBM® WebSphere® Commerce Suite product. Specifically, we focus on the problem of migrating applications that use traditional database access techniques to applications using the Enterprise JavaBean (EJB) programming model. Our results include a practical methodology that facilitates such migration, as well as a tool that supports this methodology. The tool has been released on IBM's alphaWorks site.     

信管专业中“C语言”与“数据结构”课程的整合研究

本文通过分析信管专业学生在学习＂C语言＂与＂数据结构＂过程中存在的问题,提出了将两门课程进行整合的教学模式。     

O／R mapping技术比较研究

针对当前出现的越来越多的O/R Mapping技术,对其中影响最大的几种实现技术进行了深入的研究,并通过实验数据对它们进行了详细的分析和比较。     

多概念层次上基于赋范划分距离的分类算法

应用知识发现理论与方法从大型考生信息数据库中提取隐含的、前所未知的、对决策有潜在价值的知识和规则,是当前计算机教育应用的新课题。根据网上远程考试与评价系统的特点,讨论了挖掘的目标规则类型及其挖掘算法。针对ID3算法的不足,提出了一种新的分类算法－多概念层次上基于赋范划分距离的分类算法,简要介绍了XML在知识发现过程中的应用。     

企业海量数据库的优化

当前大多数企业应用软件都需要数据库支持, 而且数据库的规模在不断扩大, 尤其用到数据仓库技术的商业智能化支持系统。面对大数据量, 企业级应用的性能愈来愈依赖数据库的性能。对数据库性能要素进行全面的描述和分析, 以便对数据库的选择、应用和基于数据库的二次开发提供工程参考。     

数据挖掘在移动通信中的应用

简单介绍了数据挖掘技术,数据挖掘所需要的条件、数据仓库的建立,以及移动通信中经常用的两种算法：决策树算法和K最近邻算法,并较为详尽地阐述了它们的工作原理。     

黑龙江省电力市场营销决策支持系统的设计与实施

针对黑龙江省电力公司现存业务处理系统的缺点,利用先进的通信技术和信息处理技术,并充分利用各个应用系统详尽的业务数据,建设基于数据仓库的电力市场营销辅助决策支持系统,详细介绍了该系统的方案设计,实现过程及应用实例,并对应用前景进行展望。实践证明,核系统在黑龙江省电力公司的实施促进了管理模式的改变及管理水平的提高。