发扬夏坚白院士精神,倡导尊重知识、重视知识产权的行业之风

前不久,报章上出现了这样一条消息:国家信息产业部、国家版权局、商务部、财政部四部委联合下发了<关于计算机预装正版操作系统软件有关问题的通知>.根据通知精神,从现在开始没有预装正版操作系统的PC产品将无法上市销售.     

搜酷

强悍的摄像机作为索尼XR系列摄像机的开篇之作,HDRXR520E集众多项级配置于一身,采用了在低光照环境下有着出色表现的Exmor R CMOS感光元件,     

中国最美的古村落(十) 浙中奇绝 乌石古村

最吸引人的是这里的建筑,古民居外墙都由一小块一小块的乌石垒成,粗犷的外形与凝重的黑色相结合,结构精巧独特,给人以"鬼斧神工"的感觉,据说最早的乌石屋已有近三百年的历史.     

电脑族每天必喝的四杯茶

1.上午一杯绿茶绿茶中含强效的抗氧化剂以及维生素C,不但可以清除体内的自由基,还能分泌出对抗紧张压力的荷尔蒙。绿茶中所含的少量咖啡因可以刺激中枢神经,振奋精神。不过最好在白天饮用,以免影响睡眠。2.下午一杯菊花茶菊花有明目清肝的作用,有些人就干脆用菊花加上枸杞一起泡来喝,或     

国家测绘局跨世纪青年学术带头人李清泉教授

李清泉教授生于1965年1月,安徽天长人,中共党员,工学博士,武汉大学副校长,湖北省第八、九届政协委员,第二届"湖北省五四青年奖章"获得者,湖北省青年联合会第十届委员会副主席,武汉市青年联合会第十届委员会副主席,李清泉教授先后承担了教学、科研、产业和财务管理以及大量社会工作.     

同江:一曲赫哲族船歌

同江位于三江平原北端,黑龙江与松花江汇流处南岸的三角地带,是有百年历史的国际口岸城市,由佳木斯市代管。清末设立临江州,1905年辟为通商口岸,1914年以黑龙江、松花江在此合一而改名同江。东接抚远,南邻饶河,北与俄列宁斯科耶隔水相望,边境线长166公里,设有国家一类口岸。同江有八岔、街津口两个赫哲族乡,这是一个只有四千人口,却在漫     

中国最美的古村落(一)千古太极奇村——俞源探秘

俞源的经典在于村落结构的设计:村中有大小七个水塘组成北斗七星的格局,村内的28幢主要建筑则按照天上的28星宿排布。     

万维网GIS的若干关键技术及其实现

提出基于J2EE多层体系结构的WebGIS系统,能够平衡好服务器、应用服务器、客户端负载,极大地提高系统的响应速度;对海量的矢量数据与影像数据采用不同的压缩方式,在数据不失真的情况下尽量减少数据的传输量,减轻网络的负载;栅格数据与矢量数据的"无缝"叠加,更加形象清楚地发布空间数据;基于0racle Spatial关系数据库的WebGIS,使系统更加安全可靠.     

飞地:孤悬在外的领土

从明清之交,到解放初的三百多年间,在(四川)峨眉县普兴乡境内,曾有一个地名叫何沟(亦叫梅沟)的小山村,只有十几户人家,却直属嘉定府管辖,毗连的夹江,峨眉、洪雅、乐山四县,无权过问,是一个"世外桃源",当地人称它是"飞地"……梅沟成为一个四不管的角落.     

数字

1.26亿吨近日,黑龙江省煤田地质勘察队在鹤岗市萝北县江滨农场境内发现一处总面积为124.88平方公里,储量约1.26亿吨,煤层平     

基于ArcObjects的组件式GIS的开发与研究

本文在组件式GIS技术发展的背景下,立足于ArcObjects组件,着重介绍其开发类型及在常用环境下的开发方法,最后以VC AO开发渐变色带ActiveX控件为例。该控件在GIS制图系统中具有较高的应用价值。     

GIS支持下的海洋水文气象信息成图模式的研究

针对海洋水文气象信息的显示需求,首先分析了其自身特点与表达习惯,并探讨了适合于海洋领域专属信息可视化表达的成图模式。基于海洋基础环境数据的地理分布特性,利用专业G IS软件ArcG IS的基本成图功能,编程实现了海洋水文气象数据可视化成图的专业应用。丰富了海洋专属信息的表达方式和内容揭示,有效地支持了海洋应用。     

Digital Geologic Mapping of the Ferron Sandstone, Muddy Creek, Utah, with GPS and Reflectorless Laser Rangefinders

The traditional approach to geologic mapping consists of sketching, taking orientation and thickness measurements with compass and tape, and noting positions of features on topographic maps or photos. These methods are time consuming, often difficult to realize in rough terrain, and poorly constrain lateral variations in sedimentary facies in relatively flat lying strata. We describe a case study that captures the three-dimensional architecture of sandstone bodies and key geological surfaces such as stratigraphic boundaries and faults using digital capture techniques. The Ferron sandstone in Utah is a superbly exposed ancient delta deposit that provides an improtant outcrop analog to fluvio-deltaic subsurface reservoirs. It has been the focus of many traditional outcrop studies, but here we use a methodology (“cybermapping”) based on GPS with offsets from a continuous ranging mode reflectorless laser rangefinder (“laser sketch”) for collection and analysis of basic stratigraphic and structural data in a relatively remote area. We also show hos this data can be analyzed and visualized in three dimensions. The study area was mapped in two days, which included hiking several kilometers into the area. One-the-fly and rapid static post processing of GPS surveying was used for positioning the reflectorness laser rangefinders; 60,000 points were acquired mapping sedimentological and structural features, terrain, and control points. The resultant quantitative 3D model of the geology and terrain allowed robust geometric visualization and analyses. ? 2001 John Wiley & Sons, Inc.     

A GIS-based decision support system for analysis of route choice in congested urban road networks

Urban congestion patterns have become ubiquitous and complex. Traditional, “static” approaches are no longer adequate for analyzing network flows and conducting minimum cost routing. This paper reports on a GIS-based decision support tool for modeling dynamic network congestion and conducting minimum cost routing. The system predicts network flows at a detailed level of temporal resolution, capturing dynamic congestion propagation effects. A Route Planner module solves for the combined departure time and minimum cost routing required for a trip to reach its destination by a given deadline. The GIS provides effective decision support through its database management capabilities, graphical user interfaces and cartographic visualization. This supports analyses of “what-if?” scenarios for strategic planning and tactical management subject to unplanned network disturbances. Received: 1 October 1999/Accepted: 21 September 2000     

基于GIS和地统计学的地理国情监测成果制图应用研究

在全国范围开展的地理国情监测是对国家基础地理信息的动态更新,对监测数据的科学分析及成果展示有利于提升数据的使用价值。本文论述了利用GIS空间分析功能和地统计学原理,对国情监测数据的变化信息进行综合制图,为地理国情监测专项成果的可视化表达提供了新的方法。     

Landslide susceptibility mapping of a catchment area using frequency ratio,fuzzy logic and multivariate logistic regression approaches

Geospatial database creation for landslide susceptibility mapping is often an almost inhibitive activity. This has been the reason that for quite some time landslide susceptibility analysis was modelled on the basis of spatially related factors. This paper presents the use of frequency ratio, fuzzy logic and multivariate regression models for landslide susceptibility mapping on Cameron catchment area, Malaysia, using a Geographic Information System (GIS) and remote sensing data. Landslide locations were identified in the study area from the interpretation of aerial photographs, high resolution satellite images, inventory reports and field surveys. Topographical, geological data and satellite images were collected, processed, and constructed into a spatial database using GIS and image processing tools. There were nine factors considered for landslide susceptibility mapping and the frequency ratio coefficient for each factor was computed. The factors chosen that influence landslide occurrence were: topographic slope, topographic aspect, topographic curvature and distance from drainage, all from the topographic database; lithology and distance from lineament, taken from the geologic database; land cover from TM satellite image; the vegetation index value from Landsat satellite images; and precipitation distribution from meteorological data. Using these factors the fuzzy membership values were calculated. Then fuzzy operators were applied to the fuzzy membership values for landslide susceptibility mapping. Further, multivariate logistic regression model was applied for the landslide susceptibility. Finally, the results of the analyses were verified using the landslide location data and compared with the frequency ratio, fuzzy logic and multivariate logistic regression models. The validation results showed that the frequency ratio model (accuracy is 89%) is better in prediction than fuzzy logic (accuracy is 84%) and logistic regression (accuracy is 85%) models. Results show that, among the fuzzy operators, in the case with “gamma” operator (λ = 0.9) showed the best accuracy (84%) while the case with “or” operator showed the worst accuracy (69%).     

A detailed study of the duality relation for the least squares adjustment in euclidean spaces

The Euclidean spaces with their inner products are used to describe methods of least squares adjustment as orthogonal projections on finite-dimensional subspaces. A unified Euclidean space approach to the least squares adjustment methods “observation equations” and “condition equations” is suggested. Hence not only the two adjustment solutions are treated from the view-point of Euclidean space theory in a unified frame but also the existing duality relation between the methods of “observation equations” and “condition equations” is discussed in full detail. Another purpose of this paper is to contribute to the development of some familiarity with Euclidean and Hilbert space concepts. We are convinced that Euclidean and Hilbert space techniques in least squares adjustment are elegant and powerful geodetic methods.     

海岸海洋潮流模拟可视化与虚拟现实建模

潮流数值模拟的科学可视化与虚拟现实是海岸海洋科学研究重要的现代技术手段之一。首先从地理信息系统的角度对潮流数值模拟系统的数据模型进行了论述，提出了适合水文数值模拟的对象模型方法；其次探讨了空间流场的可视化技术，阐述了虚拟现实在潮流数值模拟中的作用；最后设计并实现了一个海岸海洋潮流模拟虚拟现实的原型软件系统VRO－cean,并在南黄海辐射沙洲等的潮流数值模拟试验中进行了实际对比检验。     

AO OMD解读

随着GIS技术的发展，用基于COM标准的ArcObject（AO）进行GIS开发成为一种有效的途径。对AO编程、开发GIS，一个重要的关键点在于开发者具有读懂AO Object Model Diagrams（OMD）的能力。本文从如下3个角度：牢记OMD图例、标记，深刻领会OMD内蕴的地学之道和熟记OMD层次结构，来帮助GIS开发人员阅读、理解AO OMD。同时对OMD中蕴藏的GIS基本线进行了图解。     

Analysis of temporal sar and optical data for rice mapping

This study investigates the potential of multi-temporal signature analysis of satellite imagery to map rice area in South 24 Paraganas district of West Bengal. Two optical data (IRS ID LISS III) and three RADARSAT SAR data of different dates were acquired during 2001. Multi-temporal SAR backscatter signatures of different landcovers were incorporated into knowledge based decision rules and kharif landcover map was generated. Based on the spectral variation in signature, the optical data acquired during rabi (January) and summer (March) season were classified using supervised maximum likelihood classifier. A co-incidence matrix was generated using logical approach for a combined “rabi-summer” and “kharif-rabi-summer” landcover mapping. The major landcovers obtained in South 24 Paraganas using remote sensing data are rice, water, aquaculture ponds, homestead, mangrove, and urban area. The classification accuracy of rice area was 98.2% using SAR data. However, while generating combined “kharif-rabi-summer” landcovers, the classification accuracy of rice area was improved from 81.6% (optical data) to 96.6% (combined SAR-Optical). The primary aim of the study is to achieve better accuracy in classifying rice area using the synergy between the two kinds of remotely sensed data.