3D Modeling and Kinematics of the External Zone of the French Western Alps (Belledonne and Grand Chatelard Massifs, Maurienne Valley, Savoie)     

Didier Marquer  Philippe Calcagno  Jean-Claude Barfety  Thierry Baudin 《Eclogae Geologicae Helvetiae》2006,99(2):211-222

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基于IMAGIS的数字小区建模探讨   总被引：3，自引：0，他引：3  

余军  李永树 《四川测绘》2005,28(4):160-164

随着城市化水平的不断提高，对城市的规划管理也提出了很高的要求，数字城市作为数字地球的重要组成部分正是在这一背景下提出的。本文结合适普公司的IMAGIS软件，对城市小区鼍维场景建设中的相关问题进行了探讨，并以遂宁市某街区为例进行了实践。  相似文献   

地震波混合阶褶积算法模拟   总被引：6，自引：0，他引：6  

戴志阳  孙建国  查显杰 《物探化探计算技术》2005,27(2):111-114

基于正反傅立叶变换,提出了地震波模拟的混合阶褶积算法。该方法原理简单、易于实现,结合了有限差分与伪谱法的优点,具有较高的精度和计算效率,适用于地震波场的正演计算,同时还给出了二维地震波场的理论计算实例。计算结果表明,此算法模拟结果正确、精度高、速度快、能适应较为复杂地质模型,并且易于推广到各向异性介质中去。  相似文献   

吉林台爆破料应力应变关系的三轴试验研究     

侯新强  张远芳  高盟  慈军  刘红  张之科 《新疆地质》2005,23(2):194-198

通过室内大型三轴实验，研究了吉林台水库爆破料在不同级配下的应力应变关系，得到了在一定击实功下爆破料的最大干密度随细料含量变化的规律，分析了爆破料在不同级配和不同围压下应力与应变的变化规律、轴向应变与体积应变的关系及抗剪强度变化特性．从微观的角度说明了变化规律产生的原因，得出爆破料的抗剪强度随级配的变化而变化的规律．  相似文献   

北方某城市浅层地下水中有机污染物迁移转化的数值模拟研究   总被引：2，自引：1，他引：2       下载免费PDF全文

刘明柱  陈鸿汉胡丽琴 《中国地质》2005,32(3):507-511

在3次野外取水样分析的基础上，分析了研究区域有机污染特征，并根据室内实验和国内外文献资料所获取的参数，利用地下水模拟系统软件（GMS）对研究区三氯乙烯（TCE）和四氯乙烯（PCE）在地下水中的运移转化进行数值模拟研究，模拟结果表明：研究区地下水中TCE和PCE存在生物降解作用，但是反应速率很小，这表明在相当长的时间内，其浓度仍可能保持在相当的水平上。  相似文献   

城市钻孔数据地下三维地质建模软件的实现   总被引：15，自引：1，他引：15  

李亦纲  曲国胜  陈建强 《地质通报》2005,24(5):470-475

介绍了基于钻孔数据的城市地下三维地质建模软件的实现过程，提出了基于钻孔数据三维地质建模的总体思路、钻孔数据管理和层序分层方法，还介绍了软件的模块组成及应用实例。建立的软件实现了对城市钻孔数据的三维建模、可视化分析和科学管理，具有丰富的二维成图和三维显示功能，实例的应用也说明本软件是分析城市第四系构造格架和演化的有力工具。  相似文献   

Spatial process and data models: Toward integration of agent-based models and GIS   总被引：8，自引：1，他引：8  

Daniel G. Brown  Rick Riolo  Derek T. Robinson  Michael North  William Rand 《Journal of Geographical Systems》2005,7(1):25-47

The use of object-orientation for both spatial data and spatial process models facilitates their integration, which can allow exploration and explanation of spatial-temporal phenomena. In order to better understand how tight coupling might proceed and to evaluate the possible functional and efficiency gains from such a tight coupling, we identify four key relationships affecting how geographic data (fields and objects) and agent-based process models can interact: identity, causal, temporal and topological. We discuss approaches to implementing tight integration, focusing on a middleware approach that links existing GIS and ABM development platforms, and illustrate the need and approaches with example agent-based models.  相似文献   

A parametric study on the impact of satellite attitude errors on GOCE gravity field recovery     

R. Pail 《Journal of Geodesy》2005,79(4-5):231-241

In the recent design of the Gravity field and steady-state Ocean Circulation Explorer (GOCE) satellite mission, the gravity gradients are defined in the gradiometer reference frame (GRF), which deviates from the actual flight direction (local orbit reference frame, LORF) by up to 3–4°. The main objective of this paper is to investigate the effect of uncertainties in the knowledge of the gradiometer orientation due to attitude reconstitution errors on the gravity field solution. In the framework of several numerical simulations, which are based on a realistic mission configuration, different scenarios are investigated, to provide the accuracy requirements of the orientation information. It turns out that orientation errors have to be seriously considered, because they may represent a significant error component of the gravity field solution. While in a realistic mission scenario (colored gradiometer noise) the gravity field solutions are quite insensitive to small orientation biases, random noise applied to the attitude information can have a considerable impact on the accuracy of the resolved gravity field models.  相似文献   

GGM02 – An improved Earth gravity field model from GRACE     

B. Tapley  J. Ries  S. Bettadpur  D. Chambers  M. Cheng  F. Condi  B. Gunter  Z. Kang  P. Nagel  R. Pastor  T. Pekker  S. Poole  F. Wang 《Journal of Geodesy》2005,79(8):467-478

A new generation of Earth gravity field models called GGM02 are derived using approximately 14 months of data spanning from April 2002 to December 2003 from the Gravity Recovery And Climate Experiment (GRACE). Relative to the preceding generation, GGM01, there have been improvements to the data products, the gravity estimation methods and the background models. Based on the calibrated covariances, GGM02 (both the GRACE-only model GGM02S and the combination model GGM02C) represents an improvement greater than a factor of two over the previous GGM01 models. Error estimates indicate a cumulative error less than 1 cm geoid height to spherical harmonic degree 70, which can be said to have met the GRACE minimum mission goals. Electronic Supplementary Material Supplementary material is available in the online version of this article at  相似文献   

Global height datum unification: a new approach in gravity potential space     

A. A. Ardalan  A. Safari 《Journal of Geodesy》2005,79(9):512-523

The problem of “global height datum unification” is solved in the gravity potential space based on: (1) high-resolution local gravity field modeling, (2) geocentric coordinates of the reference benchmark, and (3) a known value of the geoid’s potential. The high-resolution local gravity field model is derived based on a solution of the fixed-free two-boundary-value problem of the Earth’s gravity field using (a) potential difference values (from precise leveling), (b) modulus of the gravity vector (from gravimetry), (c) astronomical longitude and latitude (from geodetic astronomy and/or combination of (GNSS) Global Navigation Satellite System observations with total station measurements), (d) and satellite altimetry. Knowing the height of the reference benchmark in the national height system and its geocentric GNSS coordinates, and using the derived high-resolution local gravity field model, the gravity potential value of the zero point of the height system is computed. The difference between the derived gravity potential value of the zero point of the height system and the geoid’s potential value is computed. This potential difference gives the offset of the zero point of the height system from geoid in the “potential space”, which is transferred into “geometry space” using the transformation formula derived in this paper. The method was applied to the computation of the offset of the zero point of the Iranian height datum from the geoid’s potential value W ₀=62636855.8 m²/s². According to the geometry space computations, the height datum of Iran is 0.09 m below the geoid.  相似文献