分布式异构环境下信息共享与服务机制研究
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摘要
目前国内数字化生产迫切需要高效、快捷地存储、管理与发布数据。特别是随着数字省建设的发展，产生的数据是异构的、海量的、分布式存储的，集中式信息管理和应用不能满足对它的分布式存储、管理和维护要求。因此就需要建立一个能够集成分布式异构数据源的信息管理与应用系统，实现信息的共享，并希望在此基础上提供一系列信息服务。
计算机技术的飞速发展使得信息共享和信息服务的实现成为可能。本文通过综合分析计算机技术现状和发展趋势，围绕数字省、数字行业信息资源的定位、共享、整合与服务的需求，提出整合跨领域、跨部门之间分布式异构数据的信息共享与服务整体框架和技术体系结构。并对其中的若干关键技术进行了研究。论文主要的研究内容与创新如下：
1．根据构建异构环境下信息共享与服务系统的需要，深入比较研究关于如何实现分布式计算机间的协同工作和业务逻辑，如何对分布式异构数据进行统一管理，如何发布和共享数据，如何发布和获取服务等方面问题的关键技术。
2．以功能强大、层次清晰、扩展性好、系统健壮、宜于维护等方面的要求为目标，按客户端应用层、门户服务层、应用服务层、数据服务层和数据存储层等五个层次构建信息共享与服务系统结构。
3．提出以“虚拟数据中心”的模式来存储与管理分布式数据。主要研究如何满足信息共享与服务系统建设中提出的多层次、多类型、大容量、分布式信息存储和管理的要求。
4．设计基于XML技术的分布式异构数据源集成方案。XML作为一种结构化的标识语言具有极强的扩展能力，已经成为应用间交换数据的一种标准。基于XML技术实现的异构数据源集成方案具有良好的通用性。
5．详细设计了基于Web Services技术的Web服务管理系统、Web服务交换平台和Web服务供应平台。实现信息服务在Internet上发布和获取。
6．结合“重大行业3S应用示范——区域”项目(国家863项目，项目编号：2002AA-13-04-08)、“数字林业”项目和“空间分析服务代理”实现，进行了实例研究。验证了本论文研究成果的合理性和可行性。
High efficiency ability to store, organize and publish data is urgent needed in the country digital production. The data produced during the process of digital province construction are heterogeneous, mass and distributed stored. The centralized organization and application of information is not matching the requirement of information distributed store, organization and maintenance. So, it is needed to setup a new form information organization and application system with the ability to integrate the distributed and heterogeneous data, further more, to provide information share and information service.
The quick development of computer technology has made it technologically possible to provide information share and service. Nowadays it is well recognized to get, publish, share and serve information by Internet. Based on the synthetic analysis of the status and the evolution trend of computer technology, generally guided by the demands of the information location, share, integration and service of the digital province and digital industry, this thesis presents the essential mechanisms of information share and service to integrate across-field, across-organization, distributed, heterogeneous information. The main work and innovation aiming at key mechanisms research goes as follows:
1. According to the demands of designing a information share and service system, the focuses placed at the researching and comparing the technology of how to implement the cooperating work between the distributed computers and the business logic, how to organize the heterogeneous data in a consistent model, how to publish and share data, how to publish and gain services.
2. Aiming at setup a system with strong functions, clear logical, good expansibility and well maintenance, system architecture is organized as five layers: client layer, portal service layer, application service layer, data service layer and data storage layer.
3. Proposing the model of "Virtual Data Center" to store and manager distributed data. Main work is placed at how to satisfy the demands of storing and organizing multi-layer, multi-type, mass and distributed information.
4. Designing the scheme to integrate distributed and heterogeneous data sources based on the XML.The XML have been a criterion of data exchanging between applications, which is a markup language enjoy good expansibility
5. Design the Web Services manager system, Web Services exchanging platform and Web Services providing platform in detail. Implement the release and gain of information services in the Internet.
6. In order to verify the above theoretical models and architecture, the author has undertaken three case studies: "Important Industry 3S Application Demonstration-region", "Digital Forestry" and "the Agent of Spatial Analysis Services ".
计算机技术的飞速发展使得信息共享和信息服务的实现成为可能。本文通过综合分析计算机技术现状和发展趋势，围绕数字省、数字行业信息资源的定位、共享、整合与服务的需求，提出整合跨领域、跨部门之间分布式异构数据的信息共享与服务整体框架和技术体系结构。并对其中的若干关键技术进行了研究。论文主要的研究内容与创新如下：
1．根据构建异构环境下信息共享与服务系统的需要，深入比较研究关于如何实现分布式计算机间的协同工作和业务逻辑，如何对分布式异构数据进行统一管理，如何发布和共享数据，如何发布和获取服务等方面问题的关键技术。
2．以功能强大、层次清晰、扩展性好、系统健壮、宜于维护等方面的要求为目标，按客户端应用层、门户服务层、应用服务层、数据服务层和数据存储层等五个层次构建信息共享与服务系统结构。
3．提出以“虚拟数据中心”的模式来存储与管理分布式数据。主要研究如何满足信息共享与服务系统建设中提出的多层次、多类型、大容量、分布式信息存储和管理的要求。
4．设计基于XML技术的分布式异构数据源集成方案。XML作为一种结构化的标识语言具有极强的扩展能力，已经成为应用间交换数据的一种标准。基于XML技术实现的异构数据源集成方案具有良好的通用性。
5．详细设计了基于Web Services技术的Web服务管理系统、Web服务交换平台和Web服务供应平台。实现信息服务在Internet上发布和获取。
6．结合“重大行业3S应用示范——区域”项目(国家863项目，项目编号：2002AA-13-04-08)、“数字林业”项目和“空间分析服务代理”实现，进行了实例研究。验证了本论文研究成果的合理性和可行性。
High efficiency ability to store, organize and publish data is urgent needed in the country digital production. The data produced during the process of digital province construction are heterogeneous, mass and distributed stored. The centralized organization and application of information is not matching the requirement of information distributed store, organization and maintenance. So, it is needed to setup a new form information organization and application system with the ability to integrate the distributed and heterogeneous data, further more, to provide information share and information service.
The quick development of computer technology has made it technologically possible to provide information share and service. Nowadays it is well recognized to get, publish, share and serve information by Internet. Based on the synthetic analysis of the status and the evolution trend of computer technology, generally guided by the demands of the information location, share, integration and service of the digital province and digital industry, this thesis presents the essential mechanisms of information share and service to integrate across-field, across-organization, distributed, heterogeneous information. The main work and innovation aiming at key mechanisms research goes as follows:
1. According to the demands of designing a information share and service system, the focuses placed at the researching and comparing the technology of how to implement the cooperating work between the distributed computers and the business logic, how to organize the heterogeneous data in a consistent model, how to publish and share data, how to publish and gain services.
2. Aiming at setup a system with strong functions, clear logical, good expansibility and well maintenance, system architecture is organized as five layers: client layer, portal service layer, application service layer, data service layer and data storage layer.
3. Proposing the model of "Virtual Data Center" to store and manager distributed data. Main work is placed at how to satisfy the demands of storing and organizing multi-layer, multi-type, mass and distributed information.
4. Designing the scheme to integrate distributed and heterogeneous data sources based on the XML.The XML have been a criterion of data exchanging between applications, which is a markup language enjoy good expansibility
5. Design the Web Services manager system, Web Services exchanging platform and Web Services providing platform in detail. Implement the release and gain of information services in the Internet.
6. In order to verify the above theoretical models and architecture, the author has undertaken three case studies: "Important Industry 3S Application Demonstration-region", "Digital Forestry" and "the Agent of Spatial Analysis Services ".
引文
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[4]M. F. Goodchild.Implementing Digital Earth: A Research Agenda, in Towards Digital Earth—Proceedings of the International Symposium on Digital Earth, 1999,p 21-26.
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[3]Al Gore. 1998, The Digital Earth: Understanding Our Planet in the 21st Century.
[4]M. F. Goodchild.Implementing Digital Earth: A Research Agenda, in Towards Digital Earth—Proceedings of the International Symposium on Digital Earth, 1999,p 21-26.
[5]M. Konecny. The Digital Earth: Spatial Data Infrastructures from Local to Global Concept, in Towards Digital Earth-Proceedings of the International Symposium on Digital Earth, 1999,p57-68.
[6]王宇翔．分布式网络地理信息系统研究：[博士学位论文]．北京：中国科学院遥感应用研究所，2002．
[7]文军，周晓聪，李师贤．分布式软件体系结构．中山大学计算机系讲义，2000年．
[8]OMG编著．CORBA系统结构、原理与规范．电子工业出版社，2000年．
[9][美]Qusay H．Mahmoud著，欧阳光，安锦译．JAVA分布式程序设计．国防工业出版社，2002年1月．
[10]飞思科技产品研发中心编著．EJB应用开发详解．电子工业出版社。2002年4月．
[11]袁安心，曾垂吕．使用CORBA进行分布式事务处理．计算机应用研究，2000年．
[12]马琳．CORBA／IIOP与XML结合的设想．计算机应用研究，2000年，P70．
[13]邵佩英．分布式数据库系统及其应用技术．科学出版社，2000．
[14]Yun-wu Huang.Spatial Joins Using R-trees: Breadth-First Traversal with Global Optimizations, Proceedings of the 23rd VLDB conference, Athens,Greece, 1997.
[15]Frantisek Brabec and Hanan Samet. Visualizing and Animating R-trees and Spatial Operations in Spatial Databases on the World wide Web, Visual Database Systems 4 (VDB4), Chapman& Hall, London, 1998, pp. 147-153.
[16]赵霈生，杨崇俊．Web．GIS的设计与实现．中国图象图形学报，2000，5(1)．
[17]郭杰华等．基于Internet的地理信息系统(WebGIS)的研究和开发．中国图象图形学报，2000．7．
[18]宋关福，钟耳顺，五尔琪．WebGIS—基于Internet的地理信息系统．中国图像图形学报，1998．3．
[19]邬群勇．空间数据管理与信息共享技术方法研究：[硕士论文]．福州：福州大学，2001．
[20]王兴玲．基于XML的地理信息Web服务研究：[博士学位论文]．北京：中国科学院遥感应用研究所，2002．
[21]典型的Web Service结构，http://www.ccidnet.com/tech/guide/
[22]微软技术教育人会—Teched 2001技术文档，http://www.microsoft.com/chinedteched/ppt/default.asp
[23]柴晓路．架构Web Service：什么是Web服务?http://www-900.ibm.com/developerWorks/en/webservices/ws-wsar/part2/index.shtml
[24] 为什么需要Web Service, http://www.mycol.com
[25] ISO/TC211 2001, ISO 19119, Geographic Information Service
[26] Open GIS Consortium, Basic Services Model Draft Candidate Implementation Specification 0.0.8, http://www.opengis.org/techno/specs.htm
[27] Allan Doyle, Carl Reed, Jeff Harrison, Mark Reichardt, Introduction to OGC Web Services, http://ip.opengis.org/ows/010526_OWSWhitepaper.doc
[28] OGC Web Services Thread set 2(OWS 1.2)-A rchitecture, March 2002. http://ip.opengis.org/ows1.2/docs/020314_OWS_1.2 Annex B.doc
[29] OpenGIS Service Framework, April 2002 http://ip.opengis.org/owsl.2/docs/020314_OWS1.2_Annex_B_appC.doc
[30] OpenGIS. Simple Features Specification For OLE/COM, May 1999 http://www.opengis.org/docs/99-050.pdf
[31] OpenGIS Simple Features Specification for CORBA, March 1998 http://www.opengis.org/docs/99-054.pdf
[32] OpenGIS. Simple Features Specification For SQL, May 1999 http://www.opengis.org/docs/99-049.pdf
[33] Geographic information - Services, http://www.isotc211.org/scope.htm#19119
[34] The OpenGIS Abstract Specification Topic 13 Catalog Services, 1999. http://www.opengis.org/docs/99-113.pdf
[35] The OpenGIS Abstract Specification,Topic 12:OpenGIS Services Architecture(ISO 19119), http://www.opengis.org/docs/02-112.pdf
[36] OpenGIS Project Document 01-024r1: Web Registry Server Discussion Paper,2001, http://www.opengis.org/docs/01-024r1.pdf
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