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岭谷组合地形的植被空间变异性对比及成因

山地学报 2009年第1期27卷 14-23页

作者：郝成元张永领吴绍洪河南理工大学测绘与国土信息工程学院中国科学院地理科学与资源研究所

滇西南山地纵向排列着老别山、邦马山、无量山、哀牢山,其对气候因子及植被生态的影响一直是我国山地生态学的主要研究内容之一。采用moran系数(MC)度量了植被主要气候因子的空间自相关程度,通过构建半变异函数研究了EVI各向异性及其气... 详细信息

滇西南山地纵向排列着老别山、邦马山、无量山、哀牢山,其对气候因子及植被生态的影响一直是我国山地生态学的主要研究内容之一。采用moran系数(MC)度量了植被主要气候因子的空间自相关程度,通过构建半变异函数研究了EVI各向异性及其气候因子的空间变异特征。结果显示:4山地气候因子的空间分异特征与地形走向吻合,表现出南-北方向的自相关程度较大,东-西方向自相关程度最小,表明山地延伸方向上'通道'作用明显而山地排列方向上'阻隔'作用显著;哀牢山和老别山的'阻隔'作用较大、景观异质性复杂,邦马山和无量山的'阻隔'作用较小、景观变化方向性不鲜明。总之,各纵向山地的'通道-阻隔'作用与各山地走向、规模大小密切相关。

关键词：岭谷组合地形增强型植被指数空间变异各向异性通道-阻隔作用

Monitoring Crustal Deformations with Radar Interferometry: A Review

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Journal of Southwest Jiaotong university(English Edition) 2004年第2期12卷 148-158页

作者：刘国祥丁晓利黄丁发 School of Civil engineering Southwest Jiaotong University Department of land surveying and Geo-Informatics The Hong Kong Polytechnic University

The crustal movements, probably motivating earthquakes, are considered as one of the main geodynamic sources. The quantitative measurements of ground surface deformations are vital for studying mechanisms of the buried faults or even estimating earthquake potential. A new space-geodetic technology, synthetic aperture radar interferometry (InSAR), can be applied to detect such large-area deformations, and has demonstrated some prominent advantages. This paper reviews the capacity and limitations of InSAR, and summarises the existing applications including some of our results in studying the earthquake-related crustal motions. Finally it gives the outlook for the future development of InSAR.

关键词： Satellite SAR interferometry Earthquake Crustal deformation Monitoring

Analysis of stability of coal pillars with multi-coal seam strip mining

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中国有色金属学会会刊：英文版 2011年第S3期21卷 549-555页

作者： ZHANG Li-ya, DENG Ka-zhong, ZHU Chuan-guang, XING Zheng-quan Jiangsu Key Laboratory of Resources and Environmental information engineering,{2. university of Mining and Technology, Xuzhou 2.1116,{2. Jiangsu Key Laboratory of Resources and Environmental information engineering China University of Mining and Technology Xuzhou 221116 China

Strip mining is one of the efficient measures to control surface subsidence and mining damage. However, the researches on the laws of the geological mining factors to upper and lower pillar's stability are still deficient in multi-coal seam strip mining at present. Based on the three dimension fast Lagrangian analysis of continua (short for FLAC3D) numerical simulation software, the laws of the stress increasing coefficient on the coal pillar and its stability were systematically studied for different depths, different mining widths, different interlayer spacings, different mining thicknesses, different properties of interstratified rock and the spacial relations of the upper and lower pillars in vertical alignment in multi-coal seam strip mining. The function relation between the stress increasing coefficient of upper and lower pillars with the mining depth, mining widths, interlayer spacing, mining thickness, property of interstratified rock and the spatial relationship were obtained.

关键词： multi-coal seam strip mining FLAC3D numerical simulation stability of coal pillar

IONOSPHERIC EFFECTS ON GPS NAVIGATION IN LOW-LATITUDE AREA

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IONOSPHERIC EFFECTS ON GPS NAVIGATION IN LOW-LATITUDE AREA

第一届交通运输工程国际学术会议

作者： GAO Shan1, 2.and CHEN Wu2.1School of Civil engineering, Southwest Jiaotong university, Chengdu, Sichuan,{2., 610031 2.ept. of land surveying and Geo-Informatics, The Hong Kong polytechnic university, Hong Kong

Ionospheric effects are the major constraints for GPS navigation. Especially, at low latitude, ionospheric delay varies greatly both in space and time. Even for short baselines, ionospheric effects cannot be cancelled out with double difference algorithm. Strong ionospheric disturbances are also observed in the region. In this paper, ionospheric behavior in Hong Kong is investigated by using a dense reference network. The effects of ionospheric disturbances on GPS receiver, such as loss of lock, gross error and measurement noise are studied.

关键词： GPS navigation ionospheric delay loss of lock cycle slip

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基于小波变换的图像压缩算法

同济大学学报（自然科学版） 2001年第10期29卷 1152-1158页

作者：程效军徐文昌陈鹰同济大学测量与国土信息工程系上海200092

根据小波变换系数分布的特性 ,提出了基于小波变换的图像无损压缩算法、高保真压缩算法和大尺寸图像压缩的解决方案 ,提出了双正交小波变换的边界处理方法。

关键词：双正交小波边界处理去相关自适应变换域编码图像压缩

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多用户全球三维仿真的数据组织与调度研究

系统仿真学报 2011年第9期23卷 1896-1899页

作者：杨靖宇张永生蔡畅信息工程大学测绘学院郑州450052 矿山空间信息技术国家测绘局重点实验室河南理工大学、河南测绘局焦作454000 江西省数字国土重点实验室抚州344000

以多用户全球三维仿真为应用背景,研究P2.环境下海量数据的多点并行分发技术。通过依据地理空间的影像分块、编码协议和Tracker服务器所维护的资源拥有节点四叉树索引列表,实现P2.网络中的快速资源定位;利用基于数据预测、缓冲思想的优... 详细信息

以多用户全球三维仿真为应用背景,研究P2.环境下海量数据的多点并行分发技术。通过依据地理空间的影像分块、编码协议和Tracker服务器所维护的资源拥有节点四叉树索引列表,实现P2.网络中的快速资源定位;利用基于数据预测、缓冲思想的优先下载策略和用户节点间的直接数据交换,提高数据分发效率。最后,通过对现有的多用户三维地形可视化系统进行改造试验,证明该方法的有效性。

关键词：对等网络并行分发四叉树地形仿真

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人工神经网络在隧道地表变形预测中的应用

同济大学学报（自然科学版） 2001年第10期29卷 1147-1151页

作者：王穗辉潘国荣同济大学测量与国土信息工程系上海200092

借助于神经网络方法处理非线性问题的优势 ,采用改进后的B -P网络算法 ,对上海地铁 2.线盾构推进中隧道上方的地表变形作了趋势预报 ,并与其它预测方法作了比较 .结果表明 :将人工神经网络用于地表变形预测 ,效果优于其它方法 .

关键词：人工神经网络地铁隧道变形预报

A probabilistic paradigm for handling uncertain objects in GIS by randomized graph algebra

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Progress in Natural Science:Materials International 2003年第9期 10-19页

作者： SHI Wenzhong and WU Huayi(Advanced Research Centre for Spatial information Technology, Department of land {2. and Geo-Informatics, The Hong Kong polytechnic university, Hong Kong, china)

Probability theory faces difficulties when it is applied to describing uncertain objects in geographic information system(GIS). This is mainly due to the fact that an object in GIS is normally described by a series of discrete vertexes. Modeling uncertainty ob-jects should be therefore based on error of the composed vertexes. This type of model is normally complex and relatively difficult to imple-ment because of many unknown factors, such as the number of vertexes of a polygon, error nature of each individual vertex and error cor-relation among the vertexes. In this paper, a probabilistic paradigm for handling uncertain objects in GIS by randomized graph algebra ispresented. The theoretical basis for this paradigm is the randomized graph algebra-a probability theory for graph-which is newly pro-posed in this study. Classical probability theory is based on numerical algebra and is also an extension of numerical algebra by further defin-ing probability density within a numerical domain. In the same token

关键词： GIS uncertain objects graph algebra measure space.

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引入时变递增因子的加权等维新息模型及预测

同济大学学报（自然科学版） 2004年第6期32卷 755-757页

作者：潘国荣王穗辉同济大学测量与国土信息工程系上海200092

从灰色系统理论入手 ,针对已发生的时间序列的一组变形观测数据 ,按其可靠性随时间成正比例变化的特性 ,引入时变递增因子来定权 ,并及时更新数据 ,用最新的数据替换老的数据 ,建立等维新息模型 ,以保证原始数据对模型的作用 ,使模型更... 详细信息

从灰色系统理论入手 ,针对已发生的时间序列的一组变形观测数据 ,按其可靠性随时间成正比例变化的特性 ,引入时变递增因子来定权 ,并及时更新数据 ,用最新的数据替换老的数据 ,建立等维新息模型 ,以保证原始数据对模型的作用 ,使模型更能反映实际 .实例计算分析表明 :该模型样本需求量小 ,计算简单 ,能动态地反映出系统的时变特性。

关键词：建筑物变形动态预测灰色系统加权模型等维新息