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231.
lintroductionGeographicinformahonSystem(GIS)hasbeendevelopedtosuchadegreethatitseemstobeakindofpanaceawhengeographicproblemsarediscussedwhereverinPapers,onclasses,inrePOrtSorinresearchplans.AtpresentitisasthoughthatgeographywasnotgeographywithoutmentioningGIS.Itremindsusofquanhtahvegeography1flatoncebroughtanewlookforgeogr'aphicresearchfromthe1960stothe1980s.DuringthatPeriod,quanhtahvegeographyhadthesimilargoodfortUnetoGIStodayasitwasfrequenhyappliedindiscussingconcernedgeognphicproblems… 相似文献
232.
Application of Mineral Exploration Models and GIS to Generate Mineral Potential Maps as Input for Optimum Land-Use Planning in the Philippines 总被引:4,自引:0,他引:4
Carranza Emmanuel John M. Mangaoang Jerrysal C. Hale Martin 《Natural Resources Research》1999,8(2):165-173
The inherent problems of classifying or inventorying potential mineral resources (as opposed to known mineral resources) pose specific challenges. In this paper, the application of a conceptual mineral exploration model and GIS to generate mineral potential maps as input to land-use policy decision-making is illustrated. We implement the criteria provided by a conceptual exploration model for nickeliferous-laterites by using a GIS to classify the nickeliferous-laterite potential of an area in the northeastern part of the Philippines. The spatial data inputs to the GIS are geological map data, topographic map data, and stream sediment point data. Processing of these data yields derivative maps, which are used as indicators of nickeliferous-laterite potential. The indicator maps then are integrated to furnish a nickeliferous-laterite potential map. This map is compared with present land-use classification and policy in the area. The results indicate high potential for nickeliferous-laterite occurrence in the area, but the zones of potential are in places where mineral resources development is prohibited. The prohibition was imposed before the nickeliferous-laterite potential was assessed by this study. Mineral potential classification therefore is a critical input to land-use policy-making so that prospective land is not alienated from future mineral resource development. 相似文献
233.
随着数字化、信息化的发展,城市部件作为城市建设、社会发展的重要载体,对智慧城市和数字城管具有重大作用.城市建设面积不断扩大,城市部件采集与管理工作压力日益增加.车载LiDAR移动测量系统作为新兴技术,近年来快速发展,将此技术应用到城市部件采集工作中,使得采集效率、安全性、精度均有较大提升.提出一套基于车载LiDAR移动... 相似文献
234.
地理信息系统集成平台框架结构研究 总被引:51,自引:3,他引:48
提出了基于客户/服务器结构的地理信息系统集成平台总体结构,探讨了基于元数据的地理信息系统数据集成平台以建立物理上分布而逻辑上集中的分布式地理信息系统数据库,提出了应用符合3NF范式的关系数据库进行模型管理的模式,在此基础上探讨了地理信息系统可视化建模工具。 相似文献
235.
A numerical method has been developed for the dynamic analysis of a tall building structure with viscous dampers. Viscous dampers are installed between the top of an inverted V‐shaped brace and the upper beam on each storey to reduce vibrations during strong disturbances like earthquakes. Analytically, it is modelled as a multi‐degree‐of freedom (MDOF) system with the Maxwell models. First, the computational method is formulated in the time domain by introducing a finite element of the Maxwell model into the equation of motion in the discrete‐time system, which is based on the direct numerical integration. Next, analyses for numerical stability and accuracy of the proposed method are discussed. The results show its numerical stability. Finally, the proposed method is applied to the numerical analysis of a realistic building structure to demonstrate its practical validity. 相似文献
236.
The existing on‐line numerical integration algorithms are derived from the Newmark method, which is based on an approximation of derivatives in the differential equation. The state–space procedure (SSP), based on an interpolation of the discrete excitation signals for piecewise convolution integral, has been confirmed as more reliable than the Newmark method in terms of numerical accuracy and stability. In an attempt to enhance the pseudodynamic test, this study presents an on‐line integration algorithm (referred to as the OS–SSP method) via an integration of the state–space procedure with Nakashima's operator‐splitting concept. Numerical stability and accuracy assessment of the proposed algorithm in addition to the explicit Newmark method and the OS method were investigated via an eigenvalue, frequency‐domain and time‐domain analysis. Of the on‐line integration algorithms investigated, the OS–SSP method is demonstrated as the most accurate method with an acceptable stability (although not unconditionally stable) characteristic. Therefore, the OS–SSP method is the most desirable method for pseudodynamic testing if the numerical stability criterion (Δt/T⩽0.5) is ensured for every vibration mode involved. Copyright © 2001 John Wiley & Sons, Ltd. 相似文献
237.
238.
The paper describes the distinctive features of the pseudo‐dynamic test method as implemented at the ELSA reaction‐wall facility. Both hardware and software aspects are considered. Particular attention is devoted to the digital control system and to a coupled numerical–experimental substructuring technique allowing realistic earthquake testing of very large structures. Mathematical and implementation details corresponding to this testing technique are given for both synchronous and asynchronous input motion. Selected test results illustrate the advantages of the presented features. Copyright © 2000 John Wiley & Sons, Ltd. 相似文献
239.
240.
利用MicroStion制作大比例尺地形图是当前规划部门的新生事物,其成图、入库工艺流程是大家关心的热点,本文重点阐述调绘、编辑、入库一体化生产的工艺流程,对实际生产具有一定的指导意义。 相似文献