基于PostGIS的异构地理空间数据组织与应用开发

PostGIS是开源关系型数据库系统PostgreSQL的空间扩展。本文分析了目前在地理信息工程领域的异构地理空间数据几种存在形式,结合PostGIS的空间数据组织方法,提出了针对PostGIS数据库的多源空间数据的集成应用方案,并在.Net开发环境中进行了可视化应用开发实践。     

地理空间索引技术研究

研究和探讨了对GIS地理数据查询产生效率影响的几种地理空间索引方法 ,并在此基础上提出了一种适合主存索引的基于对象分割的B+ 树空间索引方法。     

地理空间索引技术研究

研究和探讨了对GIS地理数据查询产生效率影响的几种地理空间索引方法,并在此基础上提出了一种适合主存索引的基于对象分割的B+树空间索引方法.     

开源Boost库在地理网络分析中的应用

介绍开源C++Boost类库,分析其在地理网络分析中的作用,BGL应用于地理网络分析中可以提高GIS程序的可复用性、封装性等性能,为基于地理网络的空间分析提供一个新的解决框架,可提高系统的开发效率和模块化程度。最后以最短路径分析为例说明BGL类库在地理网络分析中的应用方法和效果。     

基于Spark与MongoDB的地理空间大数据应用分析系统设计与实现

针对地理空间大数据应用分析中存在的技术瓶颈,提出了一种基于Spark与Mongo DB的地理空间大数据应用分析方案,深度融合了Spark与JTS拓扑套件,在此基础上研发了地理空间大数据应用分析系统,为地理空间大数据应用分析提供了一种新的方法与途径。     

地理空间分析及可视化分析研究

地理空间分析是基于地理对象的位置和形态特征的空间数据分析技术，其目的在于提取和传输空间信息，是地理信息系统的重要功能之一。随着3S技术的融合和空间信息处理技术的发展和广泛应用，地理空间分析、空间数据挖掘和知识发现以及地学可视化已经成为空间信息处理的重要手段和关键技术。本主要论述了现有的地理空间分析方法，并讨论了基于地理空间分析的海量空间数据挖掘和地学可视化分析。     

城市影像地图集的内容表达形式浅析

从分析我国城市影像地图集的内容和表现形式入手,基于对城市要素地理和空间认知效果探讨影响城市影像地图集内容表达的各种因素,并在分析比较几本具有代表性的图集表达方式基础上,提出能够满足城市地理和空间认知的城市影像地图集的内容表达形式.     

一种新的地理线要素分形插值方法

地图制图自动化已成为地理研究的重要内容，包括自动综合和自动扩充。地图中线要素的自动扩充是要通过插值来实现。传统的曲线插值方法没能反映地理线要素的分形结构、比例尺相关性、空间各向同性等特点。针对地理线要素的特点，基于分形几何理论，将Douglas-Peuker算法和随机中点移位法结合起来，提出了一种新的分形插值方法。并通过方法比较和实例分析验证了方法的可行性和有效性。     

虚拟地理环境认知与表达研究初步

分析了地理学的地理环境与当前地理信息技术中的地理空间两者概念之间的差异,探讨了地图与地理信息系统空间认知的发展及特点,初步研究了虚拟地理环境认知与表达的对象、特征与主要内容。从基于虚拟地理环境的地理认知和基于地理认知的虚拟地理环境表达两个层面分析了虚拟地理环境的认知与表达;指出虚拟地理环境的认知与表达研究不仅需要进一步发展地理空间认知理论和方法,还需要拓展对地理过程及人类行为的认知与表达理论和方法研究;并着重探讨了地理过程的表达和人类行为的模拟,指出当前虚拟地理环境认知与表达研究的关键内容。     

基于52°North WPS的地理参考系统坐标转化服务

近年来,随着网络技术、空间信息技术的发展与成熟,面向网络的空间信息服务得到了极大的发展,并推动了数据共享与管理、空间信息处理服务飞速的发展。然而,不同的数据源提供者之间具有不同的地理参考系统,不同的用户也可能需要不同地理参考系统数据。地理参考系统间的转化仍然是数据预处理的一项关键技术。本文主要介绍了空间信息服务框架下的地理参考系统转换方法、技术、流程等,整个实验过程是基于开源的空间信息服务平台52°North WPS完成的。     

GIS软件的发展方向研究

GIS软件发展到现在已经到了一个比较成熟的阶段。开源GIS的提出,从本质上为GIS软件的新发展提供了方向。开源GIS以开放、分享的特点将会成为以后GIS软件研发的主流方向。文章概述了开源GIS的基本构架、数据类型和优势特点,同时从研发角度以及商业角度分析了开源GIS的意义。     

HydrIS: An open source GIS decision support system for groundwater management (Morocco)

A regional groundwater management system has been elaborated, integrating Relational Database Management System (RDBMS) and various web services. It consists of web geospatial application so-called HydrIS (Hydrogeological Information System) based on Open Source components and technologies, leading to a feasible and low-cost solution. Therefore, HydrIS permits delivery of data from a number of heterogeneous sources to standards supported by the Open Geospatial Consortium (OGC). The protocols used for exchanging data are also derived from OGC standards, i.e., WMS (Web Mapping Service), WFS (Web Feature Service), and WCS (Web Coverage Service). Finally, a geoportal was developed, which consists of client-applications that communicate with different Web Services (WMS, WCS, and WFS) through http-requests.     

GeoWebCache瓦片地图服务中间件研究

本文以GeoWebCache开源瓦片地图服务中间件为例,剖析其工作原理和系统结构,并与传统WMS( Web Map Service)进行了性能对比,实验结果表明采用GeoWebCache中间件比直接访问WMS服务的平均响应时间减少约36％最后,从瓦片空间索引,扩展机制及系统部署策略等三个方面给出了GeoWebCache...     

地理空间情报预测分析的一种方法

地理空间情报是对影像和地理空间信息的发掘和分析。其中,地理空间情报预测分析是决策的基础。传统的地理空间情报预测分析大多是基于逻辑思维的定性研究,此处提出了一个地理空间情报预测分析的模型——因果关联图,同时给出了计算预测事件可信度的方法。该方法能够定量、简捷、快速、有效地实现地理空间情报预测分析。     

HydrIS:一个用于地下水管理的开放的GIS决策支持系统——以Morocco为例(英文)

A regional groundwater management system has been elaborated, integrating Relational Database Management System (RDBMS) and various web services. It consists of web geospatial application so-called HydrIS ( Hydrogeological Information System) based on Open Source components and technologies, leading to a feasible and low-cost solution. Therefore, HydrIS permits delivery of data from a number of heterogeneous sources to standards supported by the Open Geospatial Consortium (OGC). The protocols used for exchanging data are also derived from OGC standards, i.e., WMS (Web Mapping Service), WFS (Web Feature Service), and WCS (Web Coverage Service). Finally, a geoportal was developed, which consists of client-applications that communicate with different Web Services (WMS, WCS, and WFS) through http-requests. A prototype for web-based GIS application was designed using the deegree Framework to provide systematic interfaces and functions. This system was developed to demonstrate the value of making hydrogeological data more widely accessible through client/server architecture. This experience and knowledge already gained in this project will be a source for technology transfer and policy decisions. Otherwise, this will enable user groups to improve the management of their groundwater resources and contribute to enhanced decision support capabilities.      

Automatic search of geospatial features for disaster and emergency management

Although the fast development of OGC (Open Geospatial Consortium) WFS (Web Feature Service) technologies has undoubtedly improved the sharing and synchronization of feature-level geospatial information across diverse resources, literature shows that there are still apparent limitations in the current implementation of OGC WFSs. Currently, the implementation of OGC WFSs only emphasizes syntactic data interoperability via standard interfaces and cannot resolve semantic heterogeneity problems in geospatial data sharing. To help emergency responders and disaster managers find new ways of efficiently searching for needed geospatial information at the feature level, this paper aims to propose a framework for automatic search of geospatial features using Geospatial Semantic Web technologies and natural language interfaces. We focus on two major tasks: (1) intelligent geospatial feature retrieval using Geospatial Semantic Web technologies; (2) a natural language interface to a geospatial knowledge base and web feature services over the Semantic Web. Based on the proposed framework we implemented a prototype. Results show that it is practical to directly discover desirable geospatial features from multiple semantically heterogeneous sources using Geospatial Semantic Web technologies and natural language interfaces.     

基于空间建模的公共安全情报分析初探

空间建模及分析作为情报分析的主要技术手段之一,在欧美等国家得到了广泛实践和应用.本文在地理信息科学的主要空间模型基础上,进行了公共安全情报分析应用的研究和实践,并应用于警用地理信息系统建设中,为我国公安机关“情报信息主导警务”提供实战参考.     

A capability matching and ontology reasoning method for high precision OGC web service discovery

Finding the right spatially aware web service in a heterogeneous distributed environment using criteria such as service type, version, time, space, and scale has become a challenge in the integration of geospatial information services. A new method for retrieving Open Geospatial Consortium (OGC) Web Service (OWS) that deals with this challenge using page crawling, link detection, service capability matching, and ontology reasoning, is described in this paper. Its major components are distributed OWS, the OWS search engine, the OWS ontology generator, the ontology-based OWS catalog service, and the ontology-based multi-protocol OWS client. Experimental results show that the execution time of this proposed method equals only 0.26 of that of Nutch's method. In addition, the precision is much higher. Moreover, this proposed method can carry out complex OWS reasoning-based queries. It is being used successfully for the Antarctica multi-protocol OWS portal of the Geo-Information Web Service Portal of the Polar.