数据库垄断的成因及对策分析

学术数据库市场被少数几个出版商掌握，新的数据库商难以加入到竞争中来，因此导致了学术数据库市场的垄断问题。本文通过叙述学术数据库垄断的四个问题，即数据库定价的不合理、数据库许可权的滥用、经营者集中和数据库用户受限，提出通过开放获取、图书馆联合与立法保护来应对数据库市场的垄断问题。     

工业控制实时数据库的研究

工控实时数据库是数据库技术的一个重要应用领域。本文对工控数据库所涉及的技术问题，即数据库的要求分析，数据模型的建立，数据库的设计和实现诸问题进行了阐述，并提出相应的技术措施和实例。     

基于VB的数据库的图像处理技术

Visual Basic提供了多种访问数据库的方法，但通过ADO方式访问数据库时，图像数据不能直接存入数据库。结合基于VB的数据库实用软件的开发，讨论了实现数据库中图像动态地存取、显示、打印、滚动式浏览与组合的原理和方法，给出了一种存取数据库图象的有效方法，解决了在ADO方式下图像数据存入数据库的问题和图像的动态打印问题，给出了部分实例代码。     

面向对象的数据库的现状和发展的若干问题

本文对面向对象的数据库（ＯＯＤＢ）的性能进行了综合评价，纠正了对于面向对象数据库的一些误解，分析了尚待解决的一些问题，探讨了面向对象数据库发展的一些问题。     

Web数据库访问的安全性技术分析

信息时代的到来，促进了计算机数据库的发展，在客户/服务器模式下的Web数据库系统中，存储和管理着大量重要数据资料。基于广域网的Web数据库访问会带来很大的安全问题。该正是基于这点，通过对Web数据库的访问技术，安全性问题的分析出发，对Web数据库访问的安全性技术进行了初步分析和评价。     

通用脆弱点数据库的构建

文中指出了构建通用脆弱点数据库的重要意义，提出了该数据库应达到的标准，讨论了该数据库构建过程中的几个具体问题，给出了通用脆弱点数据库的字段结构。     

浅谈关系数据库的数据保护策略

随着计算机技术的飞速发展，数据库的应用已十分广泛，深入到了社会各个领域，但随之而来产生了数据的安全保护问题，数据库中存储了大量的信息资源，信息安全是一个重要方面。论文针对数据库中存在的一些安全问题，总结了在SQLServer中必要的数据库完整性控制和安全设置，包括身份验证和权限管理等。     

一个客户/服务器MIS系统开发中的若干数据库设计问题

考察了一个实际的信息系统，分析了数据库设计中的需求分析、整体设计、关系表确立等方面出现的问题，并提出解决方案，以使开发人员在数据库设计时避免这些问题，设计一个适用的数据库。     

关系数据库性能优化研究

效率是数据库开发中经常遇到的问题，数据库性能的优劣将直接关系到软件的运行效率。为了提高数据库产品的性能，对影响关系数据库性能的一些主要因素进行了阐述。结合实际给出了数据库性能优化的一些建议并用实验数据证明之。分析和比较了不同设计方案可能对数据库性能的影响，提出了目前关于数据库性能优化的问题是没有通用方案的观点。     

分布式系统中的多数据库远程访问

在异型数据库的增值应用中，需要解决数据库集成而引起的问题，多数据库系统提供了解决数据库集成问题有价值的方法。本项目的目的是建立模型，即透过一个简单的图形用户界面（GUI）访问远程异型数据库。简单介绍项目中的软件设计和实现方案，包括图形用户界面、通信子系统和数据库管理子系统。     

Feature extraction from ECG signals using wavelet transforms for disease diagnostics

This paper deals with a modified combined wavelet transform technique that has been developed to analyse multilead electrocardiogram signals for cardiac disease diagnostics. Two wavelets have been used, i.e. a quadratic spline wavelet (QSWT) for QRS detection and the Daubechies six coefficient (DU6) wavelet for P and T detection. After detecting the fundamental electrocardiogram waves, the desired electrocardiogram parameters for disease diagnostics are extracted. The software has been validated by extensive testing using the CSE DS-3 database and the MIT/BIH database. A procedure has been evolved using electrocardiogram parameters with a point scoring system for diagnosis of cardiac diseases, namely tachycardia, bradycardia left ventricular hypertrophy, and right ventricular hypertrophy. As the diagnostic results are not yet disclosed by the CSE group, two alternate diagnostic criteria have been used to check the diagnostic authenticity of the test results. The consistency and reliability of the identified and measured parameters were confirmed when both the diagnostic criteria gave the same results     

Thermodynamic and ab initio investigation of the Al–H–Mg system

A coupled ab initio and thermodynamic study of the Al–H–Mg system has been carried out and a self-consistent thermodynamic database has been obtained. Magnesium alanate Mg(AlH₄)₂, a candidate material for hydrogen storage, has been included into the database. According to Density Functional first principles calculations, the alanate is an insulator and its thermodynamic properties have been obtained at room temperature. This compound has been found metastable at 298.15 K and 1 bar. The alanate has been found thermodynamically stable only at high pressure when the formation of the binary β-MgH₂ phase is neglected. A reassessment of thermodynamic parameters of the liquid phase in the binary Mg–H system has also been carried out in order to be consistent with the Al–H system. The present results can reproduce reasonably well the available experimental data.     

基于X3D的交互式变电站信息可视化管理系统

针对三维信息系统并未在虚拟制造上得到广泛应用的现状，通过结合Extensible-3D(X3D)和Java程序语言，构建出一个具有人机交互效果的3D变电站信息可视化管理系统。系统的特点是可以在三维场景上直接进行信息管理操作，同时系统会将修改信息自动存入数据库中，再次运行系统时会自动重建三维场景。应用实例表明，所提出的系统架构具有交互性、可视化的管理特性，改变了过去单纯通过文字或二维文件进行信息管理的模式，对企业的虚拟化制造有着很好的借鉴作用。     

Graph-Based Parallel Query Processing and Optimization Strategies for Object-Oriented Databases

Much work has been accomplished in the past on the subject of parallel query processing and optimization in parallel relational database systems; however, little work on the same subject has been done in parallel object-oriented database systems. Since the object-oriented view of a database and its processing are quite different from those of a relational system, it can be expected that techniques of parallel query processing and optimization for the latter can be different from the former. In this paper, we present a general framework for parallel object-oriented database systems and several implemented query processing and optimization strategies together with some performance evaluation results. In this work, multiwavefront algorithms are used in query processing to allow a higher degree of parallelism than the traditional tree-based query processing. Four optimization strategies, which are designed specifically for the multiwavefront algorithms and for the optimization of single as well as multiple queries, are introduced. The query processing algorithms and optimization strategies have been implemented on a parallel computer, nCUBE2; and the results of a performance evaluation are presented in this paper. The main emphases and the intended contributions of this paper are (1) data partitioning, query processing and optimization strategies suitable for parallel OODBMSs, (2) the implementation of the multiwavefront algorithms and optimization strategies, and (3) the performance evaluation results.     

Database design practices for inverted files

Database research literature has proposed many procedures, both manual and automated, for database design; selection of secondary indexes for inverted file type database management systems (DBMS) has been repeatedly addressed. The empirical study reported here indicates that practical inverted file design has been relatively unaffected by this research.This paper characterizes the actual database design process used at inverted file DBMS installations along such dimension as: types of secondary keys constructed, the individuals who make index design decisions, the decisions that are changed (and when) after the initial database implementation, the factors that are considered in indexing decisions, and the literature which is used in the process. The study shows that key selection (as one example of a design decision) is addressed by ad hoc procedures and well conceived procedures are not used. Further, the results indicate that database design is dominated by users and systems analysts, indexes are frequently changed and a wide range of database performance and convenience factors are influential in practice. The paper concludes with some recommendations for database design support tools.     

Hi4D-ADSIP 3-D dynamic facial articulation database

The face is an important medium used by humans to communicate, and facial articulation also reflects a person's emotional and awareness states, cognitive activity, personality or wellbeing. With the advances in 3-D imaging technology and ever increasing computing power, automatic analysis of facial articulation using 3-D sequences is becoming viable. This paper describes Hi4D-ADSIP — a comprehensive 3-D dynamic facial articulation database, containing scans with high spatial and temporal resolution. The database is designed not only to facilitate studies on facial expression analysis, but also to aid research into clinical diagnosis of facial dysfunctions. The database currently contains 3360 facial sequences captured from 80 healthy volunteers (control subjects) of various age, gender and ethnicity. The database has been validated using psychophysical experiments used to formally evaluate the accuracy of the recorded expressions. The results of baseline automatic facial expression recognition methods using Eigen- and Fisher-faces are also presented alongside some initial results obtained for clinical cases. This database is believed to be one of the most comprehensive repositories of facial 3-D dynamic articulations to date. The extension of this database is currently under construction aiming at building a comprehensive repository of representative facial dysfunctions exhibited by patients with stroke, Bell's palsy and Parkinson's disease.     

Bibliographic retrieval: a survey of individual users of MEDLINE

The National Library of Medicine (NLM) has been providing online access to the MEDLINE database for nearly 20 years. In recent years, there has been a shift in the composition of the user population. Nearly half the online access codes are now held by individuals who conduct their own searches of the database. The NLM has conducted a survey to identify the demographic features of this end-user population, their reasons for searching the database, their methods of access, and their satisfaction with MEDLINE as available on the NLM system.     

数据库自然语言查询界面

数据库技术的普及使得用户对数据库应用界面的要求越来越高，以往的几类接口都需要用户有较高计算机知识水平，而且必须经过一定的培训，这样就会造成人力物力的浪费而且不利于计算机的普及。本文探讨的是一种更为方便简洁不秀学习即可操作的自然语言界面。