INVERSE DDA OF A SYSTEM OF BLOCKS IN SPHERE COORDINATES     

Wu Yun  Wang Hui  Zhou Shuoyu  Shi Shunying 《大地测量与地球动力学》2003,23(Z1)

1　IntroductionDiscontinuousDeformationAnalysis(DDA)developedbyShiin 1 980’s[1 ,2 ] maybeusedtocalculatethedeformationanddisplacementsinamulti blocksystemandtoanalyzetherelationbe tweenforcesanddisplacementsinthesystem .Ifthesurveydisplacementofeverypointordirectionisknown,alldisplacementsanddeformationsofblocks,eventheglide ,theclosureandthestretchoftheboundary planeofblocks ,canbecalculated .TheresultisoptimallyfittedaccordingtotheLeastSquarePrinciple.DDAismainlyusedinrockblockssystems…  相似文献   

A THREE-DIMENSIONAL ELASTIC NESTED-GRID MESO-(β-γ)SCALE ATMOSPHERIC MODEL——PARTI:MODEL DESCRIPTION          下载免费PDF全文

刘玉宝  周秀骥  胡志晋 《Acta Meteorologica Sinica》1993,(3)

A three-dimensional elastic nonhydrostatic mesoscale(β-γ)model with nested-grid is presented.It uses a set of fullequations in terrain-following coordinates as its basic dynamic frame,which is solved with a time-splitting algorithmfor acoustic and gravity waves.The model physical parameterization includes a K-theory subgrid eddy mixing for cloudand free atmosphere,a bulk planetary boundary layer parameterization,and three types of sofisticated cloudmicrophysics schemes with double-parameters for hail-bearing clouds,warm clouds and snowing clouds respectively.The model is designed to be used flexibly for simulations of a variety of meso-and small-scale atmospheric processes,and can be improved as a regional and local operational NWP system in future.  相似文献   

地理信息系统数据库设计     

潘珩 《成都信息工程学院学报》2006,21(4):555-558

首先分析了地理信息系统的组成、地理信息系统数据的特征、地理信息系统数据库的功能，然后进行了中心式导航系统数据库的设计，给出了数据库模型的E-R图，最后描述了空间地理信息的查询功能。  相似文献   

数字图像压缩方法在天文上的应用   总被引：1，自引：0，他引：1  

栗志  周卫红 《天文学进展》1996,(3)

概述了数字图像压缩技术在天文领域应用的必要性。针对天文观测的特点和研究的需要，经过研究、分析和比较，提出了天文图像压缩的可行方案。通过应用计算机编程及压缩实验并给出相应的结果。  相似文献   

中国石油生产的展顾     

周全浩 《云南地理环境研究》1990,2(1):1-9

本文分析了中国石油生产近20年变化的原因,对一些学者认为80年代中国会成为超级产油大国,后又悲观断定80年代中国可能变成石油净进口国作了评述。同时对90年代中国石油生产前景作了初步展望。  相似文献   

利用地震矩张量反演鲜水河断裂带现今运动学特征     

孙建中  施顺英  周硕愚  张爱华 《大地测量与地球动力学》1994,(4)

本文探讨了利用地震矩反演断裂形变带运动学参数的基本理论和方法，将其初步应用于鲜水河断裂形变带变形分析和运动机制的研究。结果表明，鲜水河断裂带呈现出走向拉伸、倾向压缩的形变格局，由地震矩反演的断裂带剪切形变速率（１０．９ｍｍ／ａ）与用地质学估算方法（１７ｍｍ／ａ）和现今地壳形变测量（８ｍｍ／ａ）的结果相当。同时，反演出的应变主方向能解释鲜水河断裂现今活动分段性特征以及多种滑动方式共存的现状，从而证明该方法是目前研究区域运动学问题切实有效的手段之一。  相似文献   

以三个代表重要思想为指导全面做好国土资源管理工作          下载免费PDF全文

周家富 《山东国土资源》2005,21(5):11-12

正在开展的保持共产党员先进性教育活动,是实践“三个代表”重要思想,加强党的执政能力建设的重要举措,也是国土资源系统进一步加强队伍建设,不断提高管理水平,全面落实“双保”工作目标,更好地服务于经济社会可持续发展的迫切要求。目前,日照市经济社会发展已进入快车道,随着市委、市政府“四大战略”的实施和“五项重点”工作的落实,日照市在推进市场化、国际化、城市化“三化”进程方面取得了巨大进步。特别是在学习考察青岛的成功经验后,全市经济社会进入了新的发展阶段。当前,既要保护好资源,又要保障经济社会发展对国土资源的需求,这…  相似文献   

Method for UAV-based 3D topography reconstruction of tidal creeks     

ZHANG Xuhui  LI Huan  GONG Zheng  ZHOU Zeng  DAI Weiqi  WANG Lizhu  Samuel DARAMOLA 《地理学报(英文版)》2021,31(12):1852-1872

It is common to obtain the topography of tidal flats by the Unmanned Aerial Vehicle(UAV) photogrammetry,but this method is not applicable in tidal creeks.The residual water will lead to inaccurate depth inversion results,and the topography of tidal creeks mainly de-pends on manual survey.The present study took the tidal creek of Chuandong port in Jiangsu Province,China,as the research area and used UAV oblique photogrammetry to reconstruct the topography of the exposed part above the water after the ebb tide.It also proposed a Trend Prediction Fitting (TPF) method for the topography of the unexposed part below the water to obtain a complete 3D topography.The topography above the water measured by UAV has the vertical precision of 12 cm.When the TPF method is used,the cross-section should be perpendicular the central axis of the tidal creek.A polynomial function can be adapted to most shape of sections,while a Fourier function obtains better results in asym-metrical sections.Compared with the two-order function,the three-order function lends itself to more complex sections.Generally,the TPF method is more suitable for small,straight tidal creeks with clear texture and no vegetation cover.  相似文献   

Dynamic Prediction Model of Overburden Settlement in Deep Mining Areas based on Space–Time Relationship     

Zhao  Kang  Zhou  Yun  Yu  Xiang  Yan  Yajing  Song  Yufeng  Wang  Junqiang  Suo  Tianyuan  Guo  Xiao 《Natural Resources Research》2021,30(5):3839-3852

Natural Resources Research - Depletion of shallow mineral resources caused by deep mining has become an inevitable trend, and deep mining can increase safety accidents and geological hazards....  相似文献   

Machine-Learning-Aided Determination of Post-blast Ore Boundary for Controlling Ore Loss and Dilution     

Yu  Zhi  Shi  Xiuzhi  Zhou  Jian  Gou  Yonggang  Rao  Dijun  Huo  Xiaofeng 《Natural Resources Research》2021,30(6):4063-4078

Natural Resources Research - In the process of open-pit bench blasting for many mines, rock fragments move in the direction of loose space after fragmentation under explosive energy, leading to ore...  相似文献