Research of Terrain 3D Visulization Method Based on IDL and Arcengine

Study on 3D terrain visualization is a hot research topic in GIS, virtual reality, computer graphics, digital photogrammetry and other fields, is also an important part of the digital earth strategy. Try to take advantage of IDL data processing and graphic display function and ArcEngine spatial analysis function, in the Visual c# under the environment of hybrid programming mechanism, use of component design and development of integrated development technologies analysis of terrain visualization application operating environment, realized the 3D digital terrain expression and spatial analysis function. The results show that the IDL and ArcEngine integrated development method applied to the 3D terrain visualization analysis software platform developed operability and extension force with strong, both in terms of space efficiency and image data analysis , development costs advantages.     

GIS数据用于复杂边坡三维极限平衡稳定分析

利用基于GIS（Geographic Information System,地理信息系统）栅格数据的三维极限平衡分析模型,可以充分考虑边坡的三维复杂空间特性。经过数据的获得、数据的处理、模型的建立和稳定性分析,不但给出了边坡的三维安全系数,而且给出了危险滑动面上的滑动力分布矢量图。结果表明,滑动面上力的分布极不均匀,呈现明显的复杂空间特性。     

Building a semantic based public transportation geoportal compliant with the INSPIRE transport network data theme

Interoperability is becoming essential for the today’s geographic information systems. Geographic information is usually available as datasets stored in databases and accessible via GIS. However, these information sources are increasingly heterogeneous and show differences in data formats, database schema and object concepts. To satisfy the increased demand for the use and sharing of geographic data in common applications, considering the heterogeneity and the methods to support interoperability are required by the GIS community. The implementation of Spatial Data Infrastructure (SDI) such as the European INSPIRE (Infrastructure for Spatial Information in the European Community) enables accessibility and the sharing of geographic data and interoperability among the systems. In addition to this, traditional GIS systems perform spatial queries using a keyword-based method. However, this approach remains incapable of fully expressing the users' needs due to a lack of geographic concepts (semantics) in the dataset. Different terms may refer to similar concepts, while the same terms may refer to different concepts. This causes semantic heterogeneity in the dataset. In this context, the most promising approach is the implementation of geospatial semantics by means of ontology in the geospatial dataset to overcome this kind of ambiguity. The aim of this research is to investigate the implementation of INSPIRE as a SDI standard and the use of Semantic Technology to empower the traditional GIS approach. In this regard, a public transportation geoportal has been developed for the experimental investigation which uses a revised sample transportation data complaint with the INSPIRE Transport Network Data Theme and a developed Transportation Ontology Domain, including concepts, relationships and individuals to provide a semantic spatial search.     

空间数据挖掘系统及其应用

近年来，空间数据挖掘系统的开发及应用已取得了极大的进展。文章在介绍已有空间数据挖掘系统的基础上，简述了空间数据挖掘与空间数据仓库、空间数据挖掘与地理信息系统的关系，阐述了空间数据挖掘的智能分析及其应用，探讨了目前空间数据挖掘系统开发及应用中存在的主要问题及未来的主要研究方向。     

基于GIS的城市规划空间辅助决策平台

城市规划管理工作越来越复杂, 利用GIS和数据库技术建立空间辅助决策平台来处理规划管理业务显得尤为迫切。介绍了空间决策支持系统(spatial decision support system, SDSS), SDSS是通过空间数据引擎(spatial data engine, SDE) 建立与商用数据库的关系与存储, 其结果体现利用了GIS的VRML和3D技术, 设计出城市规划空间辅助决策软件平台的体系结构和应用模型.文章提出了决策平台核心内容在于建立成熟完备的决策模型库和决策算子的实现过程, 以及计算结果的多样化表达.通过决策软件平台的建立能够为城市规划管理决策提供客观准确的理论依据, 为决策者科学决策奠定基础.      

跨GIS平台应用集成开发环境技术

为了突破面向业务系统及面向问题的建模技术,提高地理信息系统(geographic information system,GIS)应用系统适应需求不断变化及复用的能力,采用工作流技术结合形式语言实现应用模型精确定量数学化的有效转换,利用重载方式对空间算子的抽象与扩展来简化异构大型分析建模与应用系统构建中逻辑模型过于繁琐复杂的技术,实现空间分析建模的可视化、精确化和简单化.在此基础上,结合可视化界面搭建、功能仓库和空间资源管理,实现支持跨GIS平台的应用系统快速构建集成环境,为多领域应用系统的集成及功能复用提供手段,降低GIS应用系统的开发难度,为GIS应用不断深入和全面推广提供技术支撑.      

First steps towards an interoperable GIS — an example from Southern Lower Saxony —

In geosciences the necessity of combining geological and geophysical information as well as applying tools for designing 3D geological and geophysical models is well accepted. Nevertheless, in most cases this demand is only put into practice by file transfer between the applications. The creation of a common 3D model is complicated by the inflexible handling of new and reinterpreted data and by changing applications, heterogeneous operating systems and/or hardware platforms. We present a new approach for a component based GIS which is coupled with an object oriented database management system. The original data, as well as the derived data and the 3D models, are stored in the extensible database. Geological and geophysical 3D modeling tools have direct access to the database via the Common Object Request Broker Architecture (COREA). By this means, we obtained both the integration of the software components and independence from changing software applications and changing platforms, finally resulting in an interoperable 3D GIS.     

Usefulness of adaptive filtering for improved Digital Elevation Model generation

The Digital Elevation Models (DEMs), which represent the variation of elevation in a terrain at spatial level, are an important source of input to a variety of applications for deriving a number of terrain parameters such as relative relief, slope, aspect direction etc. In recent years, Synthetic Aperture Radar Interferometry has been viewed as a powerful approach to derive quality DEMs from a pair of SAR images. Despite the interferometric technique is often limited by several de-correlations several researchers demonstrate its effectiveness in topographic mapping. The DEM accuracy is strongly influenced by the effectiveness of the phase unwrapping technique. In this study an effective adaptive filtering approach has been used to reduce the phase noise due to de-correlation and in improving the accuracy of phase unwrapping. Two well known phase unwrapping approaches such as branch cut and minimum cost flow network have been used. Interferometric data from ASAR sensor onboard ENVISAT satellite have been used. A highly undulated terrain condition near Dehradun city situated in Uttarakhand state of India was selected to investigate the performance of this adaptive filtering approach. The RMS error between the InSAR derived elevations and the map derived elevations was obtained as 7.2 m using adaptive filter. However, elevation map of the study area could not be generated due to high de-correlation effect without the use of adaptive filter. This result clearly demonstrates the effectiveness of adaptive filtering approach for generation of DEM at meter level accuracy, which is sufficient for many engineering applications.     

航天技术在测绘、遥感和地理信息系统中的应用

简要叙述航天技术在测绘、遥感和地理信息系统中的应用现状与潜力，包括利用定位卫星的空间大地测量进行各种精度的定位测量，利用各种传感器的航天遥感进行多时相的对地观测和测图。在此基础上构成全球的、区域的和国家级的各种地理信，包系统，以满足资源调查、环境保护、灾害防治和全球变化监测的需要。从四化建设和社会持续发展需要出发，对如何发展航天应用技术提出了建设性建议。测绘、遥感和地理信息系统是一个技术十分密集、服务范围极广的先行性、基础性地理信息产业。由于计算机科学和空间科学的迅猛发展，使得测绘、遥感和地理信息系统在数据获取、信息传输、数据处理、成果显示、表达和应用诸方面更多地依赖电子计算机技术和航天技术，并逐步形成了地理信息科学和地理信息产业。     

重大工程地下环境信息系统的设计与实现

地下环境信息系统是运用岩土工程、地理学、计算机图形学、计算数学等多学科理论和方法，以GIS技术为基础，结合数据库处理、C 语言编程、OpenGL编程技术、三维图像处理技术建立的对地下环境信息进行数据综合管理和分析的大型信息管理系统。结合笔者开发的广东省东深供水改造工程地下环境信息系统特点，阐述了重大工程地下环境信息系统的功能特征：探讨了GIS二次开发的主要技术，包括：SQL Server数据库处理技术、OpenGL三维图形编程技术、C Builder面向对象编程技术、MAPGIS二次开发技术等；建立了地层三维模型，并提出了映射变换和插值技术相结合的地层切剖原理，以及在地层三维显示和分析中实用的径向基函数插值、滑动最小二乘插值、分片Lagrange插值等方法；开发了数字制图与分析、地基基础设计计算与稳定性分析、三维空间分析的主要功能；提出了地面结构景观和地下空间一体化分析的研究方向，并初步实现其分析功能。最后，在东深供水改造工程中进行了成功应用。     

泥石流调查遥感解译新方法研究

文章在分析总结近年来遥感技术在地质灾害调查评价工作应用的基础上,针对存在的不足,就区域小流域泥石流地质灾害调查评价的遥感解译应用,提出了基于虚拟GIS和水文空间分析的遥感解译方法（RSVH）。该方法综合利用虚拟GIS、遥感图像数字处理技术和空间分析技术,将大尺度区域降级为较小尺度的空间逻辑单元。针对各单元应用遥感影像和高精度DEM数据创建三维虚拟场景。同时叠加地形、地质、岩性、土壤、灾害等具有丰富属性信息的图层,较好地解决了大尺度区域范围内遥感解译工作面临的困难。为小流域地质灾害的调查工作提供了新思路。     

自适应网格在复杂地形浅水方程求解中的应用

计算域内地形的概化精度对模拟结果有较大影响,针对实际地形中同时存在狭长河谷与广阔泛洪区的问题,在层次自适应网格模型的基础上,研究了网格快速加密与合并的步骤,并以水位梯度与局部弗劳德数为基础设计了网格自适应准则,当水流运动情势变化时网格密度自动调整,实现计算精度与效率的平衡。在此网格模型基础上,采用有限体积法求解二维浅水方程,利用梯度限制器技术及龙格-库塔法提高模型的空间、时间计算精度。算例表明,层次自适应网格模型既能实现随水流运动动态变化并捕获水位计算敏感区,也能对局部区域进行静态固定加密,自适应性良好,具有较好的推广应用价值。     

航天技术在测绘、遥感和地理信息系统中的应用

简要叙述航天技术在测缓、遥感和地理信息系统中的应用现状与潜力，包括利用定位卫星的空间大地测量进行各种精度的定位测量，利用各种传感器的航天遥感进行多时相的对地观测和测图。在此基础上构成全球的、区域的和国家级的各种地理信息系统，以满足资源调查、环境保护、灾害防治和全球变化监测的需要。从四化建设和社会持续发展需要出发，对如何发展航天应用技术提出了建设性建议。测绘、遥感和地理信息系统是一个技术十分密集、服     

运用GIS技术研制石化管线管理系统

石化企业中运输各类原料和产品的管道种类繁多、空间关系复杂、安全管理要求高，因而需要应用GIS技术对石化管线实施信息化管理，于是研制了一个专门用于大型石化企业的管线管理系统。该系统在MAPGIS上开发，运用层次化的数据模型，包括图库管理、管网输入编辑、管网维护、WEB发布、辅助设计等多个子系统，采用了三维空间数据分析、虚拟现实、基于ASP和组件的管线信息WEB发布、断面图自动实时生成等新技术。该系统已在上海石化安装运行，并被证明稳定可靠。同时还介绍了系统的数据模型和总体结构、关键技术及应用前景。     

基于3D WebGIS月球地质空间数据管理系统

随着空间信息技术、地学信息技术和GIS等技术的飞速发展,利用QT结合OpenGEL技术建立基于3D WebGIS月球地质空间数据管理系统。该系统包含二维成果管理系统、发布系统与三维月球研究3个子系统,实现改善月球资料信息使用效率、信息化程度与多源空间数据共享。将中国探月计划所获取的月球地形地貌、岩层、土壤、资源、环境及各种相关数据资料与研究成果,以及国外包含数据、文献、报告等月球探测的研究最新成果集成在一起,建立了中国第一个月球地质空间数据管理系统。该信息系统既包含管理和服务功能,又提供面向科研、决策的信息服务与科学的分类管理、快速检索和联机查询的功能。地质空间数据管理系统具备强大的数据综合分析能力、综合管理月球地质资料与集成数据资料成果的汇总能力,将为中国探月工程提供有力的支撑。     

地理信息系统在滑坡灾害研究中的应用

对地理信息系统 ( GIS)技术在滑坡研究中的应用现状作了分析 ,并介绍了笔者在该方面的一些研究成果 ,认为只有在数据获取、GIS与滑坡专业模型的集成、GIS与遥感的集成等方面有较大的突破之后 ,才能充分发挥 GIS在滑坡研究中的作用。     

面向移动空间信息服务的可移植嵌入式GIS平台

智能终端和移动互联网的快速发展使得移动空间信息服务成为数字城市和数字地球的重要内容,而各种基于定位导航的嵌入式地理信息系统(geographic information system,GIS)也逐步成为这类信息服务的主要方式.分析了现代移动空间信息服务的特征,采用层次式模块化的方法,介绍了基于GIS的可移植抽象层、多元数据存储模型、电子地图显示引擎和高性能应用服务引擎等关键模块的设计,设计了可移植的嵌入式GIS平台,为通用的移动空间信息服务移动端的应用开发提供了一个切实可行的方案.      

基于GIS边坡稳定三维极限平衡方法的开发及应用

由于GIS强大的功能从一般的数据存储到复杂的空间分析及图形显示,在岩土工程分析中亦必将成为一个常用工具。本文研究基于GIS栅格数据和4个边坡稳定三维极限平衡模型,开发了一个GIS扩展模块用于边坡三维安全系数计算。考题和实例计算表明了该模块的正确性和便利性。     

Geographical information system-based computational implementation and application of spatial three-dimensional slope stability analysis

Three-dimensional (3D) evaluation of slope stability is a widely addressed problem in the domain of geotechnical engineering. The growing popularity of the geographical information system (GIS) approach, with capacities ranging from conventional data storage to complex spatial analysis and graphical presentation, means that it is also becoming a powerful tool for geotechnical engineers. In this study, in which we combine GIS grid-based data with four proposed column-based models of 3D slope stability analysis, we have devised new correspondent GIS grid-based 3D deterministic models to calculate the safety factor of the slope. Based on the four GIS-based 3D slope stability analysis models, a GIS-based program, 3DSlopeGIS, has been developed to implement the algorithm where all the input data are in the same format as the GIS dataset. The 3DSlopeGIS system, which is an extension of the widely used GIS software package, represents the combined development of 3D slope stability analysis and GIS-based component object model (COM) skills. Since all related data are supplied in the GIS format, this new database approach will be convenient for the repeated renewal and consulting of data. Certain widely addressed examples are evaluated in this paper and the results show the correction and potential of this GIS-based tool as a means of assessing the 3D stability of a slope. Two practical slope problems have been evaluated using the 3DSlopeGIS system. The results illustrate the convenience of data management as well as the effective range selection of Monte-Carlo random variables and the critical slip surface location in some parts of a lava dome.     

GIS-based spatial and temporal prediction system development for regional land subsidence hazard mitigation

An integrated GIS-based approach for establishing a spatial and temporal prediction system for groundwater flow and land subsidence is proposed and applied to a subsidence-progressed Japanese coastal plain. Various kinds of fundamental data relating to groundwater flow and land subsidence are digitized and entered into a GIS database. A surface water hydrological cycle simulation is performed using a GIS spatial data operation for the entire plain, and the spatial and temporal groundwater infiltration quantity is hereby obtained. Through the data transformation from the GIS database to a groundwater flow code (MODFLOW), a 3D groundwater flow model is established and unsteady groundwater flow simulation for the past 21 years is conducted with results which compare satisfactorily with observed results. Finally, a Visual Basic code is developed for land subsidence calculations considering aquifer and aquitard deformation. Future land subsidence in the plain is predicted assuming different water pumping scenarios, and the results provide important information for land subsidence mitigation decision-making.