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借助于计算机技术和互联网技术，空间信息的共享有了飞速的发展，特别是在国际标准化组织ISO/TC211和OGC的推动下，空间信息Web服务的相关规范已经相当的成熟。越来越多的GIS部门和研究机构将自己的空间数据以Web服务的形式发布。但是大量的空间信息Web服务被发布到互联网却没有为之提供一个完善的检索机制，大大影响了空间信息资源的充分使用和数据共享服务的实现。大量闲散的网络地图服务充斥着互联网，如何将这些WMS收集起来，并为之提供一个良好的检索机制，使得用户可以方便的找到他们所需要的WMS，最后将这些WMS进行集成已成为一个十分迫切的要求。

因此，本文试图运用当前迅速发展的搜索引擎技术与Web Service 技术，对网络地图服务的搜索与集成方面进行研究，并结合实际需求建立相应的原型系统。论文主要研究内容如下：

• 在充分分析了当前网络空间信息搜索与集成方面的研究进展和技术后，设计了一种面向OGC Web地图服务的搜索引擎框架，并在该框架下，实现了对符合OGC WMS规范的Web地图服务的网络自动化搜索与管理。
• 分析了网络地图服务集成过程中的各项技术难题包括参考坐标系的不一致问题，如何保持图层的相对地理位置不变，如何避免图层被拉伸变形，返回图层的透明性问题以及客户端浏览器坐标与地理坐标的转换等问题，并给出了相应的解决方案。
• 在开源软件资源下，设计并实现了网络地图服务搜索和集成原型系统。该系统充分利用网络资源，将互联网中的WMS元数据信息收集整理，为用户提供一个方便的查询机制，并实现对WMS的动态连接和可视化的集成。该系统基本解决了用户对多个网络地图服务的搜索与集成的需求。

With the rapid development of computer technology and internet technology, the sharing of spatial information has developed quickly in recent years. Specially under the impulse of the international organization for standardization ISO/TC211 and OGC, the specifications of spatial information web service have been quite mature. More and more GIS departments and research institutes published their spatial data in the form of web service. However, a large number of spatial information web services were published to internet with no retrieval mechanism has greatly affected the full use of information resources and spatial data services. So, how to collect these web map services and provide a good search mechanism for the users to find what they need, then integrate these web map services has become an urgent need.
In this paper, the author carried out deep researches on search and application integration of web map services using the latest web service technology and search technology. The contents are as follows:

• Based on the analysis of current network spatial information search and integration technology, a framework of search engine for OGC web map services is presented. This search engine is designed to search and manage online web map services which conformed to OGC web map service specifications.
• The key technical problems on integration of web map services are discussed, including the problem of inconsistent reference coordinate system, how to maintain the relative geographical position of map layers, how to avoid the layers being distorted, how to maintain the output map layers transparently, how to transform between the customer end browse coordinates and geographic coordinate. A series of solutions are proposed at the same time.
• A prototype system of web map service search engine is designed and implemented based on open source software resources. This system is capable of discovering available web map service servers dynamically, saving and updating capabilities information of them into relational database. For each spatial information request form clients, it can choose qualified web map service servers according to the request autonomously and fetching the matched geographical information for them form remote web map service servers transparently. It has basically solved requests of users on search and integration of web map services.

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