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21.
GIS专题数据综合的研究   总被引:7,自引:0,他引:7  
随着GIS技术在各种应用领域的推广使用,各领域的专业数据与G1S的空间数据相结合,形成描述特定地理现象的各种专题数据。与GIS空间数据一样,专题数据的应用也由微观的、较为详细地描述小区域地理现象特征,转向宏观的、较为概略地描述较大范围地理现象特征,这是专题数据综合的主要任务。该文在讨论GIS专题数据类型及特征的基础上,着重分析了专题数据综合的基本类型,并提出了专题数据综合的概念模型,为GIS专题数据自动综合的实施提供理论依据和实施方案。  相似文献   
22.
We initially estimated the cropland area at county level using local historical documents for the Songnen Plain (SNP) in the 1910s and 1930s. We then allocated this cropland area to grid cells with a size of 1 km × 1 km, using a range of cultivation possibilities from high to low; this was based on topography and minimum distances to rivers, settlements, and traffic lines. Cropland areas for the 1950s were obtained from the Land Use Map of Northeast China, and map vectorization was performed with ArcGIS technology. Cropland areas for the 1970s, 1980s, 1990s, 2000s, and 2010s were retrieved from Landsat images. We found that the cropland areas were 4.92 × 104 km2 and 7.60 × 104 km2, accounting for 22.8% and 35.2% of the total area of the SNP in the 1910s and 1930s, respectively, which increased to 13.14 × 104 km2, accounting for 60.9% in the 2010s. The cropland increased at a rate of 1.18 × 104 km2 per decade from the 1910s to 1970s while it was merely 0.285 × 104 km2 per decade from the 1970s to 2010s. From the 1910s to 1930s, new cultivation mainly occurred in the central SNP while, from the 1930s to 1970s, it was mainly over the western and northern parts. This spatially explicit reconstruction could be offered as primary data for studying the effects of changes in human-induced land cover based on climate change over the last century.  相似文献   
23.
BOOK REVIEWS     
Books reviewed in this article: Aerial Photography and Remote Sensing Aerial photography and image interpretation for Resource Management . DAVID P. PAINE . Analytical Models and Techniques Spatial Processes Models and Applications A. D. CLIFF AND J. K. ORD Quantitative and Statistical Approaches to Geography: A Practical Manual JOHN A. MATTHEWS . Cartography and Maps Map Data Processing . HERBERT FREEMAN AND GOFFREDO G. PIERONI , eds. Computer-assisted Cartography: Principles and Prospects, 1982 . MARK S. MONMONIER . Cultural Navajo Architecture: Forms, History, Distributions . STEPHEN C. JETT AND VIRGINIA E . SPENCER . Rational Landscapes and Humanistic Geography . EDWARD RELPH . Economic The Structure and Control of a State Economy . W. L. L'ESPERANCE . Economic Geography . JAMES O. WHEELER AND PETER O. MULLER . The Myth of the Family Farm: Agribusiness Dominance of U.S. Agriculture . INGOLF VOCELER . Libya: The Experience of Oil . J. A. ALLEN . Geography of Public Finance, Welfare Under Fiscal Federalism and local Government Finance . ROBERT BENNETT . Environmental Management, Resources, and Systems Mountains and Man . LARRY W. PRICE . Environmental Geology . DONALD R. COATES . An Introduction to Environmental Systems . G. H. DURY . The Environment: Chinese and American Views . Edited by LAURENCE J. C. MA AND ALLEN G. NOBLE . Land Use in America . RICHARD H. JACKSON . Medical Conceptual and Methodological Issues in Medical Geography . MELINDA S. MEADE (ed.). Philosophy and Geographic Thought Birds in Egg/Eggs in Bird . GUNNAR OLSSON . PhysicaI Climatology: Selected Applications . J. E. OLIVER . Geomorphological Techniques . ANDREW GOUDIE (ed.). Political Politics, Geography and Behaviour . RICHARD MUIR AND RONAN PADDISON . The State of the World Atlas . MICHAEL KIDRON AND RONALD SECAL . Population The Population of the South . DUDLEY L. POSTON , JR . AND ROBERT H. WELLER , eds. Regional Latin America: Economic Development and Regional Differentiation . ARTHUR MORRIS . Developing the Amazon . EMILIO F. MORAN . Western Europe: A Systematic Human Geography . BRIAN W. ILBERY . Settlement Systems in Sparsely Settled Regions: The United States and Australia . RICHARD E. LONSDALEAND JOHN H. HOLMES , eds. African Perspectives: The Economic Geography of Nine African States . HARM DE BUJ AND ESMOND MARTIN , eds. Rural Nonmetropolitan America in Transition . AMOS H. HAWLEY AND SARA MILLS MAZIE , eds. Social Crime and Environment . R. NORMAN DAVIDSON . The Ghetto: Readings with Interpretations . JOE T. DARDEN , ed. Urban Urban Problems and Planning in the Developed World . MICHAEL PACIONE (ed.) Problems and Planning in Third World Cities . Edited by MICHAEL PACIONE . The City in West Europe . D. BURTENSHAW , M. BATEMAN , AND C. J. ASHWORTH .  相似文献   
24.
Prokopenko and Kendall (J Paleolimnol doi:, 2008) criticise the work presented in Fedotov et al. (J Paleolimnol 39:335–348, 2008), and instead propose an alternative interpretation for the grain-size evolution recorded in the KDP-01 core, retrieved from the central part of Lake Khubsugul. Their interpretation is based (i) on a seismic-stratigraphic re-interpretation of sparker seismic profile khub012 (which they copied from Fedotov et al. (EOS Trans 87:246–250, 2006)), (ii) on the presupposition that changes in lake level are the dominant control on facies distribution in Lake Khubsugul, and (iii) on the invalidation of our age-depth model. In this reply to their comment, we demonstrate that they interpreted seismic artefacts and geometries caused by changes in profile orientation as true stratigraphic features and that the lake-level reconstruction they derive from this interpretation is therefore incorrect. We also demonstrate that their grain-size predictions, which they consider to be predominantly driven by changes in lake level, are inconsistent with the measured sulphate concentration, which is a demonstrated proxy of lake level in Lake Khubsugul, and with the measured grain-size record. Finally, we point out that even if there would be a problem with the age-depth model, this problem would not affect the part of the sedimentary sequence discussed in Fedotov et al. (J Paleolimnol 39:335–348, 2008).  相似文献   
25.
Microseismic systems at five mines in the Sudbury Basin provide the basic data for Falconbridge Limited's rockburst research. Daily and long-term analysis of this data as well as underground observations have confirmed the fault-slip mechanism at three mines. A detailed analysis of the complete history of Falconbridge Mine is being conducted and Distinct Element numerical models are being used to simulate both the stick-slip behaviour of faults and the dynamic effects of the induced vibrations on rock and backfill. University research includes acoustic tomographic imaging of the rock mass based on seismic wave propagation and collection of full microseismic waveforms to allow application of advanced seismic and statistical analysis techniques.Formerly with Mines Technical Services, Falconbridge Limited, Sudbury Operations, Falconbridge , Ont., P0M 1S0.Presented at the Fred Leighton Memorial Workshop on Mining Induced Seismicity, Montreal, Canada, August 30, 1987.  相似文献   
26.
本文系统阐述了国家自然地图集Internet版的设计和研制过程中的若干问题,包括系统的概念设计、系统开发中的WebGIS技术和策略,系统的主要功能和特色,以及系统维护和更新方案等。本系统从概念设计来看分为服务器端软件模块、浏览器端软件模块、国家自然地图集数据库支持等几个部分。系统开发中采取的WebGIS技术和策略有:兼顾服务器端和客户端的综合型WebGIS策略,基于Java Applet的 WebGIS浏览器开发技术,基于Map Object(MO)的WebGIS服务器开发技术等3个方面。在系统的主要功能特色方面,本文从以下5个方面进行了论述:科学有序的内容结构、清晰精练并带导航的界面、富有特色的信息查询功能、多重表达的地图可视化效果、一定的空间信息分析和制图功能。在系统维护和更新方案上,本文从网络技术、数据更新、功能开发3个方面介绍了计划,并对今后的发展趋势进行了展望。  相似文献   
27.
罗伟玲  王艳阳  张恒 《热带地理》2020,40(1):110-118
以广州市为例,基于城市感知数据、遥感影像等多源数据,采用卷积神经网络对遥感影像进行了语义提取,将提取结果与兴趣点(Points of Interest)样方密度的功能用地识别结果进行补充校验,根据政策和规划文件建立功能用地与主体功能区之间的关联,利用信息熵分析广州市功能用地混合程度,以辅助判别主体功能区,最终得到广州市主体功能区划分结果。将划分结果与《广州市主体功能区规划(2008—2020年)》和《广州市城市总体规划(2017—2035年)》草案对比验证,结果表明文章所提出的方法精准度较高,并能体现广州市空间格局形态,反映主体功能区实际分布情况。  相似文献   
28.
利用TM数据提取干旱区土地覆被信息的方法比较   总被引:5,自引:3,他引:5  
以柴达木盆地香日德绿洲作为研究实验区,对该区域ETM遥感数据经过空间分辨率融合、主成分分析等方法进行空间信息增强及专题信息增强处理,组合最佳视觉背景图像,分别在不同背景图像上选择训练样本,利用最大似然法监督分类方法(MLC)、多空间尺度分层聚类(SSHC)和基于知识的模糊聚类方法(KFC)等分类器,分别用各自训练样本初始化各类别信息特征值,形成类别特征值模式库,分别以此为基础对待分样本进行分类,对初分类的结果经过类别合并、碎斑滤除以及重新编码赋色等分类后处理,得到最终分类结果及分类精度评价结果。从所获数据可以得出如下结论:从总体精度和Kappa值可知,SSHC和.KFC分类方法所获结果精度较高,总体精度比MLC分类结果约高于3%,SSHC之结果精度略高于KFC之结果;SSHC、KFC和MLC三种分类方法对该区域地表覆被信息的提取分类中,SSHC分类方法对耕地、石砾地、河滩和荒漠分类结果较好,KFC分类方法对耕地、沙地、河滩和荒漠分类结果较好,MLC分类方法对耕地、河滩和荒漠分类结果较好,三种分类方法对耕地、河滩和荒漠等三种地类的分类精度较高,用户精度都在80%以上,而对沙地和石砾地的分类结果其用户精度大都低于80%。  相似文献   
29.
徐刚  郑达兴  乔子江  于新兵 《地质通报》2009,28(08):1047-1052
DEM和RS技术是研究滑坡地质灾害的重要资料和手段。近年来,随着高空间分辨率遥感卫星和高精度雷达卫星的上天,可以获取现时性高精度的DEM,使滑坡地质灾害的研究由二维向三维提升。利用IRS-P5数据生成的5m精度的DEM,借鉴GOOGLE的三维可视性原理,将其和高空间分辨率QuickBird(0.61m)数据叠置到数字地球之上,制作成三维可视性图像,进行滑坡环境指标参数提取方法研究。研究结果表明,该方法可直接读取滑坡环境指标的三维参数,具有客观、准确、快速的特点,可为滑坡灾害评估和区域地质灾害危险性评价提供定量化资料。  相似文献   
30.
Spatial clustering is widely used in many fields such as WSN (Wireless Sensor Networks), web clustering, remote sensing and so on for discovery groups and to identify interesting distributions in the underlying database. By discussing the relationships between the optimal clustering and the initial seeds, a clustering validity index and the principle of seeking initial seeds were proposed, and on this principle we recommend an initial seed-seeking strategy: SSPG (Single-Shortest-Path Graph). With SSPG strategy used in clustering algorithms, we find that the result of clustering is optimized with more probability. At the end of the paper, according to the combinational theory of optimization, a method is proposed to obtain optimal reference k value of cluster number, and is proven to be efficient.  相似文献   
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