基于PowerBuilder与MSSQLServer集成开发环境的若干问题

在大型信息系统开发过程中，提供良好的人机界面和优异的应用系统性能，一直是信息系统开发者所追求的目标之一。文章针对数据的并发存取、Ｃ／Ｓ体系结构，索引的建立以及人机界面等几个方面的问题，探讨了在ＰＢ与ＭＳＳＱＬＳｅｒｖｅｒ集成环境下，信息优化设计的若干策略。     

A Real-Time TCP Stream Reassembly Mechanism in High-Speed Network

With the continual growth of the variety and complexity of network crime means, the traditional packet feature matching cannot detect all kinds of intrusion behaviors completely. It is urgent to reassemble network stream to perform packet processing at a semantic level above the network layer. This paper presents an efficient TCP stream reassembly mechanism for real-time processing of high-speed network traffic. By analyzing the characteristics of network stream in high-speed network and TCP connection establishment process, several polices for designing the reassembly mechanism are built. Then, the reassembly implementation is elaborated in accordance with the policies. Finally, the reassembly mechanism is compared with the traditional reassembly mechanism by the network traffic captured in a typical gigabit gateway. Experiment results illustrate that the reassembly mechanism is efficient and can satisfy the real-time property requirement of traffic analysis system in high-speed network.     

基于DGPS技术的动态对象实时定位跟踪系统设计与实现

探讨了利用ＤＧＰＳ技术对动态对象进行实时定位跟踪系统的设计模型及所采且的技术实现方案，并着重分析了差分ＧＰＳ技术的原理及其在此类系统中的应用；给出了构造此类所需解决的主要技术问题及相应的技术方案，以及此项研究的达到的若干主要技术指标。     

几种Web数据库访问方法及比较

文章围绕Ｗｅｂ数据库访问技术的发展，就几种Ｗｅｂ数据库的动态访问方法，应用特征，构造机制以及存在的问题进行了分析和比较。     

基于ISA的Web数据库访问方法研究

给出了在ＶｉｓｕａｌＣ＋＋平台下通过Ｉｎｔｅｒｎｅｔ服务器访问Ｗｅｂ数据库的一种方法，包括ⅡＳ与ＩＳＡ应用程序之间的数据交换，数据访问和动态网页生成机制，并给出了方法与其它Ｗｅｂ数据库访问方法的比较。     

Image Betrayal Checking Based on the Digital Fingerprint of Images on the Internet

In the Internet environment, documents are easily leaked, and divulged files spread rapidly. Therefore, it is important for privacy institutions to actively check the documents on the Internet to find out whether some private files have been leaked. In this paper, we put forward a scheme for active image betrayal checking on the Internet based on the digital fingerprint, which embeds fingerprints into privacy documents, extracts codes from the Internet images, and then finds out the divulged files by matching two groups of codes. Due to so many documents on the Internet, the number of times of code comparison is huge, which leads to a large running time. To overcome the deficiency in practical application, we optimized the process by accurate matching methods and approximate matching method. Then a method was proposed to group objects by locality sensitive hashing (LSH) process before code comparison, in order to eliminate the vast majority of unrelated pairs. Experiments prove that this method could operate with less running time and less memory.