Use of Fuzzy Membership Input Layers to Combine Subjective Geological Knowledge and Empirical Data in a Neural Network Method for Mineral-Potential Mapping

Use of GIS layers, in which the cell values represent fuzzy membership variables, is an effective method of combining subjective geological knowledge with empirical data in a neural network approach to mineral-prospectivity mapping. In this study, multilayer perceptron (MLP), neural networks are used to combine up to 17 regional exploration variables to predict the potential for orogenic gold deposits in the form of prospectivity maps in the Archean Kalgoorlie Terrane of Western Australia. Two types of fuzzy membership layers are used. In the first type of layer, the statistical relationships between known gold deposits and variables in the GIS thematic layer are used to determine fuzzy membership values. For example, GIS layers depicting solid geology and rock-type combinations of categorical data at the nearest lithological boundary for each cell are converted to fuzzy membership layers representing favorable lithologies and favorable lithological boundaries, respectively. This type of fuzzy-membership input is a useful alternative to the 1-of-N coding used for categorical inputs, particularly if there are a large number of classes. Rheological contrast at lithological boundaries is modeled using a second type of fuzzy membership layer, in which the assignment of fuzzy membership value, although based on geological field data, is subjective. The methods used here could be applied to a large range of subjective data (e.g., favorability of tectonic environment, host stratigraphy, or reactivation along major faults) currently used in regional exploration programs, but which normally would not be included as inputs in an empirical neural network approach.     

基于网格的空间信息模型与服务技术研究

空间信息基础设施是实现数字城市的核心与基础，现有的万维网已经不能满足空间信息访问与处理的需要。该文对以空间信息为核心和基础的数据网格——空间信息网格的基础理论及网格中的空间信息模型与服务技术：进行研究。提出了空间信息网格的若干关键技术及网格中的空间信息模型的特点与要求，并对空间信息网格服务进行了初步的探讨。     

多维植被信息系统及其应用前景

3S(地理信息系统GIS、遥感RS、全球定位系统GPS)及其相关技术的发展，使得植被信息系统的构建和应用成为可能。早期的植被图没有涉及到高度维和时间维，其应用受到很大的限制。因此有必要建立一种基于时空的多维植被信息系统，它的组成包括地理信息系统GIS、数据处理模块DPM、数据存取模块DAM、植被分析模块VAM和交互显示模块IDM，可用于植被的时空分析、三维景观显示、植被—地形—气候关系研究以及植被综合管理等方面，特别适合于山地植被的研究。多维植被信息系统具备立体直观的用户友好界面和强大的时空数据处理能力，并可通过数据库和网络进行资源共享，使植被研究和管理自动化、无纸化，其应用前景广阔。     

云南省防洪空间信息系统构建

通过讨论应用地理信息系统（GIS）技术，立足现实对相关空间数据进行集成和整合处理，实现防洪空间信息的数字化、标准化，为优化防汛指挥工作手段提供基础。系统数据库饭知不同比例尺精度的空间基础数据以满足不同目的的需求，对相关水文、防洪设施、全省洪涝风险和重点区风险图、土地利用等图件进行系统整合。系统有较强的管理功能和分析功能，可提高云南省防洪空间信息的共享度和系统有效管理，为政府统一组织和指挥抗洪救灾提供重要的辅助决策支持手段。     

辽宁省抚顺市区地质灾害监测系统设计方案

抚顺市地质灾害监测系统，由5方面工作内容组成：(1)建立统一可靠的城市高程起算基准；(2)扩展现有的沉降监测网，使分散的监测点联合形成全面、统一的监测网；(3)对浑河断裂带主断层实施监测；(4)对西露天采坑北坡滑坡重点区和采煤沉陷重点区实施水平位移监测；(5)利用计算机技术和地理信息系统(GIS)技术，建立抚顺市地质灾害信患系统。该系统是城市地质灾害防治的基础工程。系统应用了先进的监测手段及数据处理技术。文章介绍了系统的设计方案。     

基于GIS的陕西省旬阳地区滑坡灾害危险性区划

西部地区是我国地质灾害的重灾区。随着西部大开发战略的实施，该地区即将开展大规模的基础建设、能源开发等。区域内的经济发展与地质灾害的矛盾将不可避免地暴露出来。为解决这一问题，论文选取中国滑坡重灾区的江汉流域开展灾害危险性区划应用研究。研究区选在旬阳地区的县城近郊，通过MAPGIS软件平台及其二次开发的滑坡灾害分析系统，采用规则网格单元划分方法，运用信息量模型对该区斜坡稳定性进行了．空间定量预测，并依信息量法的结果编制了该区的危险性预测分区图。为政府部门进行土地规划决策、避免在地质灾害易发区进行大规模土地开发和工程建设提供了科学依据。     

Seismic risk assessments and GIS technology: applications to infrastructures in the Friuli–Venezia Giulia region (NE Italy)

This paper illustrates the seismic risk preliminary estimates of two different groups of structures located on the territory of the Friuli–Venezia Giulia region (NE Italy) : the first group includes some special industrial plants, and the second group includes bridges and tunnels belonging to the regional highway network. The part of the study on special industrial plants tries to evaluate the degree of expected damage, taking into account their structural typology and ground shaking expressed in terms of macroseismic intensity. The second part of the study is an application of the HAZUS methodology to the tunnels and bridges of a highway network: the combination of expected ground shaking and the construction characteristics lead to very different risk levels, especially when considering the bridges. The resulting damage levels to bridges and tunnels are still only indicative because of the fragility curves used in the evaluations: they were developed for existing bridge and tunnel structural typologies in the U.S.A. Moreover, both examples show the power of GIS technology in storing, elaborating, and mapping spatial data. Copyright © 2003 John Wiley & Sons, Ltd.     

防汛信息共享与元数据应用研究

分析了FGDC、CEN／TC287等元数据标准，讨论了基于GIS的防汛信息共享与元数据的应用，设计了防汛信息元数据库，实现了元数据支持下的防汛信息共享。     

数字土地信息系统的集成模式探讨

简述土地管理的特点,分析土地信息系统的组成,具体介绍如何实现数字土地信息系统的集成。     

基于MapXtreme的地理信息发布

随着近年来计算机技术的发展,尤其是网络技术的发展,GIS在组成结构和应用技术等方面已与传统的GIS技术有了很大的不同,基于MapXtreme/MapX的WebGIS则是GIS技术发展的趋势。本文简单介绍WebGIS的发展趋势,结合一些例子介绍了利用MapXtreme的地理信息发布的技术和原理。