基于Web的数据库连接池技术的设计与实现

以Java的JDBC对数据库的传统连接方式和基于Web的数据库连接池技术分别做了介绍,并对两者进行了比较。同时给出了一个我们完成的连接池实现例,该程序实现了对多种类型数据库的处理,并且分别在Oracle817、Access2000、SQLServer2000和Mysql-3.23.49-win下调试通过。     

基于Java的数据库连接池的设计与优化

通过分析传统数据库开发模式的不足,提出了数据库连接池技术,并对其基本模型和设计方案分别做了探讨。在静态连接池的设计基础上,提出了动态连接池的优化模型,给出了构造该模型的不同部件类以及它们的基本属性和方法,实现了对连接池的灵活配置。动态连接池技术可以极大地提高数据库的访问效率。     

动态多连接池实现高效地数据库访问

连接池技术是实现高效数据库访问的一种重要手段,本文在分析现有连接池技术的基础上,提出了一种真正的动态、多连接池的实现方案.该方案通过多连接池的不同配置,实现严格的访问权限控制;多连接池采取统一管理,发生请求碰撞时,分别在不同的连接池挂起等待,实现多用户并行连接池访问;依据连接池运行的历史数据,作为进一步连接池配置的参数,从而实现连接池配置管理动态化、自动化.在实现动态多连接池管理的同时,也加强了数据库访问的安全控制,同时还实现了异构数据库管理系统(DBMS)的统一访问.实验结果表明,该方案可以有效地的提高数据库访问效率,同时实现数据库的细粒度访问控制.     

基于Java的数据库连接池技术研究

介绍了Java中使用的数据库连接技术——JDBC,综述了四种基于JDBC的数据库访问机制,比较各自的优缺点：分析了连接池工作原理及其优势．并且在Tomcat服务器上用JavaBean实现了SQLServer2000的数据库连接池。     

基于JDBC与设计模式的数据库连接池实现方法

目前Jave数据库应用程序中存在着通过JDBC访问数据库时频繁创建、关闭Connection对象的做法.这种做法对并发访问量大的应用会带来较大的性能开销.针对这一问题,提出并实现了一个基于JDBC与设计模式相结合的数据库连接池实现方法,该方法从连接池对象和连接池管理者两个方面实现对Connection对象的管理,Connection对象使用完后不去关闭而是放回到连接池中以达到复用的目的,从而提高了Java数据库应用的效率.     

基于Java的数据库连接池技术研究

介绍了Java中使用的数据库连接技术——JDBC,综述了四种基于JDBC的数据库访问机制,比较各自的优缺点,分析了连接池工作原理及其优势,并且在Tomcat服务器上用JavaBean实现了SQL Server 2000的数据库连接池。     

异构数据库集成中间件的设计与实现

随着信息产业和通信技术的发展,企业在信息化建设过程中构建起多个异构的信息系统.为了解决网络环境中异构数据库的数据集成和共享问题,提出了一种基于XML和数据库连接池的异构数据库集成中间件模型.在此模型中设计了翻译器、分发器、集成器,分别用于数据的格式转换、分解和合并,并对模型实现过程中的关键技术给出了详细描述.为了进一步提高数据库访问效率,引入了数据库连接池技术,实现了分布式异构数据库的透明访问和联合查询.     

数据库连接池模型的分析与优化

介绍了数据库连接池(Connection Pool)的原理及其模型,通过对连接池的控制参数和调度策略的分析,提出了几种相关的优化措施;最后举例介绍了在Web应用中数据库连接池的实现方法.     

数据库连接池技术研究和实现

数据库和数据库连接池技术已经得到了广泛的应用,数据库连接池建立的例子也很多。本文先简要介绍了数据库连接池的概念,然后分析了连接池的管理,即:连接池建立、连接池管理和连接池关闭。随后介绍了如何在基于Java的基础上建立连接池:定义连接池类、创建管理类、管理类与主程序的接口。最后简要分析了数据库连接池的优化架构,优化的主要目标是能动态调整连接池的容量,避免资源浪费。     

基于J2EE的JDBC数据库连接池技术研究与应用

通过介绍分析Java访问数据库的原理及其存在的问题,提出了数据库连接池方法,并对其关键技术和使用时应注意的问题进行了分析,最后构建了一个简便易用的连接池并结合当前热门技术Servlet说明了如何在开发中使用连接池.     

Only connect: teaching, technology and telesis

Abstract This paper describes an approach to the design of interactive multimedia materials being developed in a European Community project. The developmental process is seen as a dialogue between technologists and teachers. This dialogue is often problematic because of the differences in training, experience and culture between them. Conditions needed for fruitful dialogue are described and the generic model for learning design used in the project is explained.     

European Community policy and the market

Abstract This paper starts with some reflections on the policy considerations and priorities which are shaping European Commission (EC) research programmes. Then it attempts to position the current projects which seek to capitalise on information and communications technologies for learning in relation to these priorities and the apparent realities of the marketplace. It concludes that while there are grounds to be optimistic about the contribution EC programmes can make to the efficiency and standard of education and training, they are still too technology driven.     

一种自适应子融合集成多分类器方法

融合集成方法已经广泛应用在模式识别领域,然而一些基分类器实时性能稳定性较差,导致多分类器融合性能差,针对上述问题本文提出了一种新的基于多分类器的子融合集成分类器系统。该方法考虑在度量层融合层次之上通过对各类基多分类器进行动态选择,票数最多的类别作为融合系统中对特征向量识别的类别,构成一种新的自适应子融合集成分类器方法。实验表明,该方法比传统的分类器以及分类融合方法识别准确率明显更高,具有更好的鲁棒性。     

煤矿井下安全监控分站的设计及其仿真实现

为了设计一种具有低成本、低功耗、易操作、功能强且可靠性高的煤矿井下安全分站,针对煤矿安全生产实际,文章提出了采用MCS-51系列单片机为核心、具有CAN总线通信接口的煤矿井下安全监控分站的设计方案;首先给出煤矿井下安全监控分站的整体构架设计,然后着重阐述模拟量输入信号处理系统的设计过程,最后说明单片机最小系统及其键盘、显示、报警、通信等各个组成部分的设计;为验证设计方案的可行性与有效性,使用Proteus软件对设计内容进行仿真验证,设计的煤矿井下安全监控分站具有瓦斯、温度等模拟量参数超标报警功能和电机开停、风门开闭等开关量指示功能;仿真结果表明:设计的煤矿井下安全监控分站具有一定的实际应用价值.     

Avoiding semantic and temporal gaps in developing software intensive systems

Development of software intensive systems (systems) in practice involves a series of self-contained phases for the lifecycle of a system. Semantic and temporal gaps, which occur among phases and among developer disciplines within and across phases, hinder the ongoing development of a system because of the interdependencies among phases and among disciplines. Such gaps are magnified among systems that are developed at different times by different development teams, which may limit reuse of artifacts of systems development and interoperability among the systems. This article discusses such gaps and a systems development process for avoiding them.     

基于QTE的蒙古文显示机制研究与实现

蒙古语言是中国蒙古族使用的通用语言,由于蒙古文区别于其他文字的书写方式和其自身变形机制等特点,在很多通用的文字处理引擎中都不被支持。在嵌入式产品开发与应用领域中Linux加QTE已经成为流行方式。该文给出了一种在QTE环境上实现基于标准Unicode的蒙古文点阵显示和变形算法, 并自定义了支持蒙古文的QTE组件,扩展了QTE功能,为在Linux加QTE方式的嵌入式体系结构中处理蒙古文提供了一种解决方法。     

Designing economic np control charts: A programmed simulation approach

This paper presents control charts models and the necessary simulation software for the location of economic values of the control parameters. The simulation program is written in FORTRAN, requires only 10K of main storage, and can run on most mini and micro computers. Two models are presented - one describes the process when it is operating at full capacity and the other when the process is operating under capacity. The models allow the product quality to deteriorate to a further level before an existing out-of-control state is detected, and they can also be used in situations where no prior knowledge exists of the out-of-control causes and the resulting proportion defectives.     

基于AD9626的模拟信号采集存储卡设计

自然界的绝大部分信号都是以模拟的形式存在,因此模拟信号的采集转换存储在数字时代十分关键。文章讨论了在雷达信号处理领域基于AD9626的AD采集存储卡的设计原理、硬件结构和程序设计与芯片配置等问题,为今后相关领域的研究提供了可参考的方案。     

The development of robot art

Going through a few examples of robot artists who are recognized worldwide, we try to analyze the deepest meaning of what is called “robot art” and the related art field definition. We also try to highlight its well-marked borders, such as kinetic sculptures, kinetic art, cyber art, and cyberpunk. A brief excursion into the importance of the context, the message, and its semiotics is also provided, case by case, together with a few hints on the history of this discipline in the light of an artistic perspective. Therefore, the aim of this article is to try to summarize the main characteristics that might classify robot art as a unique and innovative discipline, and to track down some of the principles by which a robotic artifact can or cannot be considered an art piece in terms of social, cultural, and strictly artistic interest. This work was presented in part at the 13th International Symposium on Artificial Life and Robotics, Oita, Japan, January 31–February 2, 2008     

A human-computer interface for non-computer specialists

The COM teleconferencing system was designed to be easy to use for both beginners and people with much computer experience. A number of design choices in organizing the human-computer interface were considered very carefully. These design problems are not unique for teleconferencing applications, but will appear in many other developments of human-computer interfaces for non-computer specialists. This report discusses naming conventions, menu format, user commands, help facility and the treatment of ‘type ahead’ from the users.