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计算机工程与应用 2009年第30期45卷 188-193页

作者：谢兴谢玉波秦前清武汉大学测绘遥感信息工程国家重点实验室武汉430079

受到基于模型和基于结构的纹理分析方法的启发,提出一种新的特征提取方法—有限混合纹理模式。纹理特征采用聚类的方法进行计算,避免了基于模型方法复杂的参数求取过程,同时也突破了基于结构的方法纹理表达能力不足的问题。在该特征的... 详细信息

受到基于模型和基于结构的纹理分析方法的启发,提出一种新的特征提取方法—有限混合纹理模式。纹理特征采用聚类的方法进行计算,避免了基于模型方法复杂的参数求取过程,同时也突破了基于结构的方法纹理表达能力不足的问题。在该特征的基础上,给出相应的纹理分割框架,并通过定量和定性实验验证了所提算法的有效性。

关键词：有限混合纹理模式局部变化模式纹理分割

Research on spatiotemporal change of ecological capacity and driving forces in the LRGR

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Science Bulletin 2007年第S2期 74-81页

作者： WEN MinXia LIU ShiLiang CUI BaoShan state key {2. of Water Environment Simulation,School of Environment,beijing Normal University,beijing 100875,china

The Longitudinal range-gorge region(LRGR)is a key region for biodiversity protection in *** It is notable for rich resources,complex environment and vulnerable *** the LRGR,there are greet differences in ecological security level and ecological *** disturbance and ecosye- tem chengee are *** the apatiotemporal changee of ecological capacity is of impor- tance for government to implement ecological *** the counties in the LRGR core re- gion ee e case,with the help of gis,we used ecological footprint method to study the spatiotemporel change of ecological capacity at two scales—the larger scale of city and smaller scale of *** we discuseed the driving factors that affected ecological capacity by principal component analysis (PCA).The results showed that the ecological footprint,ecological capacity and ecological security level varied distinctly from county to county in the *** ecological capacity decreased year by year from the north,south to the middle of *** to the analysis of driving forces,per capita ecological capacity had a negative correlation with population,GDP,and other driving factors. Among these factors,social economy and population hed very significant impacts on ecological ca- *** the spatiel variation of driving factors determined the spatiotemporal change of ecological capacity.

关键词： LRGR ecological capacity ecological footprint principal component analysis

Spatial distribution characteristics of urban thermal conditions: application of gis and remote sensing

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Journal of Geographical Sciences 2001年第3期11卷 261-270页

作者： ZHOU Hong-mei1, ZHOU Cheng-hu2. GE Wei-qiang1, DING Jin-cai3 (1. Shanghai Meteorological Institute, Shanghai 2.0030, china 2. state {2. laboratory of Resources and Environment Information System, Institute of Geographic Sciences and Natural Resources state key {2. of Resources and Environment Information System Institute of Geographic Sciences and Natural Resources Research CAS Shanghai Meteorological Institute Meteorological Center

The urban thermal distribution characteristics and its variation are dynamically monitored and synthetically analyzed by using gis technology. The meteorological satellite data serve as main information source, assisted as auxiliary information sources by the landsat satellite TM data, land use thematic maps and meteorological observed data. A correlated pattern on the ground surface brightness temperatures and air temperatures has been studied and established with good performance of application.

关键词： remote sensing geographic information system urban thermal distribution application and study

An equal area conversion model for rasterization of vector polygons

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Science china Earth Sciences 2007年第S1期 169-175页

作者： ZHOU ChengHu1, OU Yang 1, YANG Liao2.& QIN Biao3 1 state key {2. of Resources and Environmental Information System, Institute of Geographic Sciences, and Natural Re-sources Research, chinese academy of Sciences, beijing 100101, china 2.Xinjiang Institute of Ecology and Geography, chinese academy of Sciences, ürümqi 830011, china 3 Mathematics Department of Xi’an Transportation University, Xi’an 710009, china

Vector-raster conversion is one of the classic research topics in the field of Geographical Information Systems (gis). The algorithms commonly used in gis are devoted to maintaining the vector polygons' shape characteristics, but neglect the gain and loss of a polygon's area, which is another important attribute. This paper proposes an equal-area conversion model based on an area compensation optimization principle. According to the topological relationship among polygons and boundary grids, a neighborhood compensation principle was adopted to assign the attributes of boundary grids and a global optimization algorithm was developed to minimize area distortion in the whole data set. Two experiments were designed and the results indicated that this algorithm not only guaranteed the area error is as small as possible, but also has the advantage as being adaptive to polygon shape and spatial structure.

关键词： vector polygon vector-raster conversion boundary grid area distortion boundary geometric characteristics

Spatial distribution of wind erosion and its driving factors in china

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Journal of Geographical Sciences 2001年第2期11卷 127-139页

作者： ZHANG Guo-ping~1, ZHANG Zeng-xiang~1, LIU Ji-yuan~2.(1. Institute of Remote Sensing Application, CAS, beijing 100101, china 2. Institute of Geographic Sciences and Natural Resources Research, CAS, beijing 100101, china) Institute of Remote Sensing Application CAS Institute of Geographic Sciences and Natural Resources Research CAS

Based on remote sensing and geographic information system, the spatial distribution of nation-wide wind erosion is studied, and the 1∶100 000 national map of soil erosion by wind in china is made. Wind speed, soil dryness,NDVI, soil texture and the slope of land surface are the key factors to wind erosion. The relations between wind erosion and each factor are discussed. The method of principal component is used to pick up the information included in the five factors, and the wind erosion dynamic index (WEDI) is established. Its comparison with theRS/{2. derived data shows thatWEDI can reflect the potential capacity of soil erosion by wind. The dynamic process of the wind erosion is studied to reveal the distribution of the most intense wind erosion regions and the dominant factors in these regions. All these studies may greatly help the mitigation of wind erosion of soil.

关键词： remote sensing geographic information system wind erosion of soil desertification control in china WEDI

Effect of pouring temperature on thixotropic microstructure formation of AZ91

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Rare Metals 2007年第S1期26卷 180-184页

作者： NING Zhiliang1),WU Peilian1),Wang H.2.,CAO Fuyang1),and SUN Jianfei1)1) School of Materials Science & engineering,Harbin Institute of Technology,Harbin 150001,china 2. Faculty of engineering & surveying,University of Southern Queensland,Toowoomba,Queensland 4350,Australia Harbin Inst Technol Sch Mat Sci & Engn Harbin 150001 Peoples R China Univ So Queensland Fac Engn & Surveying Toowoomba Qld 4350 Australia

The effect of pouring temperature on thixotropic microstructure of AZ91 was *** results show that the pouring temperature has a pronounced effect both on microstructural morphology and grain *** decreasing the pouring temperature,the morphology of grains changes from coarse dendritic to fine dendritic *** fine dendritic structure that was obtained at low pouring temperature developed into a globular structure with a grain size of 60 μm,if the AZ91 was partially remelted and held isothermally at the semisolid state(575 ℃).On the other hand,if the alloy was poured at a high superheat,the particles were irregular and interconnected with a grain size of 180 μm even after 2. min of isothermal holding.

关键词： pouring temperature semisolid microstructural evolution

SPATIAL ANALYSIS ON ECOSYSTEM DEGRADATION OF GRASSLAND IN XILINGUOLE WITH RS AND gis

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SPATIAL ANALYSIS ON ECOSYSTEM DEGRADATION OF GRASSLAND IN XI...

Using gis Spatial Distribution to Predict Soil Organic Carbon in Subtropical china

第三世界生态高峰会

作者： Feng X.M.~(*1) Zhao Y.S.~2.~1 state key {2. of Urban and Regional Ecology,Research Center for Eco-Environmental Sciences.chinese academy of Sciences.Beijng 100085,china ~2.College of Resources and Environment,Graduate School of the chinese Academ of Sciences,beijing 100049,china

Grassland in Inner Mongolia is vulnerable *** is an important belt to protect North china from sandy weather,but it has been degraded in recent decades for the climate variety and human *** this paper,CENTURY model was introduced to describe dynamic of grassland in Xilinguole,which lays in the middle of Inner *** model was validated with field data from 1991 to 1995 of Xilinhaote and Zhenglanqi observation *** relation between the modeled aboveground biomass （AGB） and the field data in Xilinhante is y=0.8783x,with R=*** is y=1.0854x in Zhenglanqi,with R=*** shews CENTURY is applicable in *** order to get the dynamic of the whole research area,a spatial database was built based on *** included data such as temperature,precipitation,AGB,soil water content （SWC）,vegetation cover and land use map,with AGB and SWC inversed from remote sensing *** AGB from 2.01 to 2.02.was *** modeled value on August,2.02.was compared with the remote sensing investigated *** think difference between them was mainly caused by failing in considering the human *** the spatially grazing distribution of the research area was got with an iterative adjusting *** shows that there is grazing on south of Xilinhaote, southwest of Xiwuzhumuqin and northwest of Keshiketengqi;while grazing in Abagaqi is *** can be concluded that remote sensing investigated surface characters work at two points in this ***,it was input parameters of CENTURY,acting as driving factor of the ***,it was the compared value of the modeled one,acting as the calculating control factor.

关键词： AGB SPATIAL ANALYSIS ON ECOSYSTEM DEGRADATION OF GRASSLAND IN XILINGUOLE WITH RS AND gis SWC

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Pedosphere 2004年第4期14卷 425-431页

作者： CHENGXian-Fu SHIXue-Zheng YUDong-Sheng PANXian-Zhang WANGHong-Jie SUNWei-Xia statekey{2.ofSoilandSustainableAgriculture InstituteofSoilScienceChineseAcademyofSciencesNanjing210008（China）. Departmentofgeography AnhuiNormalUniversityWuhu241000（China）

Spatial distribution of organic carbon in soils is difficult to estimatebecause of inherent spatial variability and insufficient data. A soil-landscape model for a region,based on 151 samples for parent material and topographic factors, was established using a gisspatial analysis technique and a digital elevation model (DEM) to reveal spatial distributioncharacteristics of soil organic carbon (SOC). Correlations between organic carbon and topographicfactors were analyzed and a regression model was established to predict SOC content. Results forsurface soils (0-2. cm) showed that the average SOC content was 12.8 g kg^(-1), with the SOC contentbetween 6 and 12.g kg^(-1) occupying the largest area and SOC over 2. g kg^(-1) the smallest. Also,soils derived from phyllite were the highest in the SOC content and area, while soils developed onpurple shale the lowest. Although parent material, elevation, and slope exposure were allsignificant topographic variables (P 2.= 0.611) and DEM (with a 30 m X 30 mgrid), spatial distribution of SOC could be forecasted.

关键词： digital elevation model parent material regression model soil organiccarbon topography

Spatial distribution analysis of landslides triggered by 2.08.5.12.Wenchuan Earthquake,china

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Spatial distribution analysis of landslides triggered by 200...