With the rapidly developing of distributed computing technique , component technique of oop n network technique and prevalence of internet in society living , webgis - - combination of www and gis , is rapidly becoming the most important of development of gis 随着分布式计算技术、面向对象的构件技术、网络技术的迅速发展，以及internet在社会生活中的日益普及，出现了与www相结合的gis ? ? webgis并迅速成为目前gis发展的最重要的方向。
However , mobile agent is the outcome combining the distributed compute technology with the artificial intelligence technology . mobile agents have a lot of pivotal technology that need to be researched and to b e explored . one of them is the security problem 但移动agent是分布式计算技术和人工智能技术相结合的产物，它还有许多关键技术需要人们去研究和探索，安全问题就是其中之一，应把这些潜在的优点与它们暴露出来的安全威胁相权衡。
The system uses relational database management system for storage and . management of network flow data . by use of java technology and its distributed computing environment , the system separates business layer from data layer commendably . thus it has preferable extensibility and portability 本系统在采用大型关系数据库对流量数据进行存储和管理的同时，采用java及其分布式计算技术，很好的实现了逻辑业务层与数据层的分离，从而有较好的扩展性和可移植性。
Distributed computing techniques usually describe those distributed application systems whose aims are sharing resource and cooperating with each other . thercfore , they are usually developed > deployeds managed and maintened on the network computing platform . currently , three models of the software component are ? rban dcom and java ejb 分布式计算技术通常是指在网络计算平台上开发、部署、管理和维护以资源共享和协同工作为主要应用目标的分布式应用系统，有代表性的分布式软件构件模型有corba 、 dcom和javaejb 。
With the rapidly development of distributed computing technology , oriented - object component - based technology , network technology , distributed gis is an important research area of gis , webgis is the combination of gis and web , the applied domain of gis expand to every field of the society and gis becomes to the public information tool 随着分布式计算技术、面向对象的构件技术、网络技术的迅速发展，传统的gis向着信息共享的网络gis发展。 webgis是gis与网络的有机结合，它使gis的应用领域扩展到社会的方方面面，成为了大众化的信息工具。
With the rapid development of modern network communication technology , control technology and distributed computing technology , the distributed & open remote monitoring system based on three - tiered network architecture has been applied increasingly in many fields . railway signaling system is the essential part to protect the railway working in safety . so remote railway station signaling monitoring system ( rrssms ) , which is an important part of the railway information system and play a key role to guarantee railway working with high efficiency and safety , will bring considerable benefits 随着网络通信技术、控制技术和分布式计算技术的飞速发展，基于三层网络体系结构的开放分布式远程监控系统开始在各行各业中得到应用，铁路站场信号系统是铁路行车调度和行车安全的基础，因此，铁路站场信号远程监控系统是信息化铁路的重要组成部分，对于实现铁路运输的安全高效具有非常重要的意义，可以带来很可观的经济效益。
In this paper , in chapter 1 and chapter 2 , the geographic information sharing technology and the distributed computing based on web services are introduced . in chapter 3 , the open gis specifications that are being implemented by open gis consortium , and open geo - data interoperability specifications are introduced . in chapter 4 , open grid services architecture , open grid services infrastructure and the ogsi . net platform are introduced 论文第一、二章介绍了地理信息共享的相关技术,重点介绍了web服务的分布式计算技术;第三章介绍了开放的地理信息互操作平台opengis及其服务框架和互操作规范ogis ;第四章介绍了开放网格服务体系结构ogsa 、开放网格服务基础设施ogsi和基于
The thesis provide a blue print to the distributed telemedicine system ( dts ) which is based on corba . with the anylysis of dts ' s system requirement under corba foundation , the object - oriented method and the characteristic of distributed object computing ( doc ) , we design a system architecture according with dts and discuss some key points in applying distributed computing technolegy ( dct ) to build dts 在分析了基于corba的分布式远程医疗系统需求的基础上，利用面向对象的方法，结合分布式对象计算的特点，设计了符合分布式远程医疗系统的特点的系统层次架构，讨论了应用分布式计算技术构建远程医疗原型系统的过程中的一些关键技术，并予以实现。
Distributed computing technology is the key of distributed system implement now although various solutions of distributed computing can be choose , they have common limitation : they are not fit for development of application in internet which is a loose - coupling environment there is no indeed solution that can realize the remote information exchange and communication between different applications on the different platform 分布式计算技术是实现分布式系统的关键。目前虽然有着多种著名的分布式计算解决方案可以选择，但它们都有着很大的缺陷：它们都不适合在internet的松耦合环境下进行系统的设计开发工作，也没有真正意义上完整的异构平台中不同应用程序之间进行远程通讯的解决方案。
