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北京林业大学学报 2007年第S2期29卷 305-305页

作者： Professor Feng Zhongke Director of Institute of GIS,rs &gps,beijing Forestry University

Effects of raster resolution on landslide susceptibility mapping:A case study of Shenzhen

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Science China(Technological Sciences) 2008年第S2期51卷 188-198页

作者： TIAN Yuan,XIAO ChenChao,LIU Yu & WU Lun Institute of rs and GIS,Peking University,beijing 100871,China Institute of rs and GIS Peking University Beijing China

Resolution has been playing a significant role in landslide susceptibility mapping and hazard *** on geographical information system(GIS) and information model,the effects of raster resolution on landslide susceptibility mapping are studied in a central area of Shenzhen,*** factors are selected to calculate landslide susceptibility with eleven groups of different resolutions(5 to 190 m).It has been found that a finer resolution does not necessarily lead to a higher accuracy of landslide susceptibility mappings,while the result of 90 m-resolution has the best accuracy and the 150 m-resolution has the worst *** accuracy curve is in a shape of "W" along with resolution decreasing:1) The accuracy decreases from 5 to 70 m;2) and then the best accuracy appears at 90 m,which is almost the same as the mean size of landslides in study area;3) the accuracy decreases again from 110 to 150 m;4) and finally the accuracy increases from 150 to 190 *** sensitivity analysis indicates that the effects of raster resolution are mainly caused by the resolution impact on landform parameter derivation,while factors like geology and human activity are very insensitive to resolutions.A further study shows that in flat,ridge,and slope foot terrains,the susceptibility mapping result is sensitive to resolution,but in the sloping surface area the sensitivity is much less sensitive to *** last,by choosing study areas with different sizes,it has also been found that the optimal resolutions are variable due to size of study *** the study area is larger than a threshold,which is 135 km2 in this study,and the optimal resolution is almost fixed.

关键词： resolution sensitivity landslide susceptibility mapping digital elevation model(DEM) information model

Integral ear elimination and virtual point-based updating algorithms for constrained Delaunay TIN

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Science China(Technological Sciences) 2008年第S1期51卷 135-144页

作者： WU LiXin1,2,WANG YanBing2,3 & SHI WenZhong2,4 1 Institute for Geo-informatics & Digital Mine Research,Northeastern University,Shenyang 110004,China 2 Institute for GIS/rs/gps & Subsidence Engineering Research,China University of Mining & Technology,beijing 100085,China 3 Laboratory of 3D Information Acquisition & Application,Capital Normal University,beijing 100037,China 4 Center for Advanced GIS Research,LSGI,Polytechnic University Hong Kong,Hong Kong,China Institute for Geo-informatics & Digital Mine Research Northeastern University Shenyang China Institute for GIS/rs/gps & Subsidence Engineering Research China University of Mining & Technology Beijing China Laboratory of 3D Information Acquisition & Application Capital Normal University Beijing China Center for Advanced GIS Research LSGI Polytechnic University Hong Kong Hong Kong China

Constrained Delaunay Triangular Irregular Networks (CD-TIN),a kind of special data structure,have many practical applications in Geoinformatics,especially in the representation of linear constrained triangulation for DTM and DSM,such as in digital city and digital mine. Past researches on D-TIN mainly focused on point in-sertion and deletion without consideration of constraint,and that on CD-TIN usu-ally paid more attention to the insertion algorithms for points and edges,but little to the deletion algorithms. The presented algorithms are far insufficient for the dy-namic updating of CD-TIN. In this paper,the constraint edge in CD-TIN is consid-ered to be any set of broken lines,i.e.,polygon edges,broken lines and simple segments. The constraint edge may be composed of one or more constraint seg-ments,and it is allowed to be in any form: Open or close,intersection or self-in-tersection. By improving to present insertion and deletion algorithms for D-TIN,two new algorithms for CD-TIN updating are presented. According to the polymorphism of the constraints in CD-TIN,virtual point is adopted to represent the crossing node between constraint edges when a constraint edge is inserted in CD-TIN. Two new algorithms named as Integral Ear Elimination (IEE) and Influence Domain Retrian-gulation for Virtual Point (IDRVP) are presented,the former is for constraint point deletion,while the later is for the insertion and deletion of constraint edge. The principle of IDRVP is that to divide the influence domain of a virtual point into some parts by the constraint-keeping edges,and to retriangulate each part of the influ-ence domain individually referring to the constraint visible property and constraint empty circle (CEC) criterion. Finally,a prototype system is developed with VC++,one case on the integration of 3D terrain and buildings is demonstrated to test the correctness of new algorithms. It shows that the new algorithms are effective for the updating of CD-TIN.

关键词： Delaunay TIN spatial constraint data updating spatial modeling polymorphism digital mine

Investigating spatial distribution of tourist attractions’inlinks: A case study of three mountains

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Science China(Technological Sciences) 2010年第S1期53卷 126-133页

作者： ZHANG Yi 1,QI LiNa 2,YANG AnRan 1,SHI Lei 1 & XU Li 1 1 Institute of rs and GIS,Peking University,beijing 100871,China 2 Center for Recreation and Tourism Research,Peking University,beijing 100871,China Institute of rs and GIS Peking University Beijing China Center for Recreation and Tourism Research Peking University Beijing China

In hyperlink analysis,most researchers focus on interpreting hyperlink counts,they seldom concern themselves enough about the significance of spatial distribution of *** this paper,we argue that not only can the inlink count to a tourist attraction’s official website reflect its attractiveness,but also the spatial distribution of its inlinks can reflect the distribution of its tourist source *** mountains in Anhui Province,China,are chosen for the case ***,the correlation between the spatial distributions of an attraction’s tourist source markets and its official website’s inlinks is ***,the tourism indexes such as the spatial concentration index(SCI)and the attraction radius(AR),which are calculated by inlinks,are compared to the real indexes based on tourist ***,the detailed discussion and analysis are presented and an improved model,which is used to calculate the distribution of inlinks,is proposed.

关键词： tourist attractiveness hyperlink analysis spatial distribution of hyperlinks tourist source market

Natural eco-environmental evaluation of eastern Qinghai-Tibet Plateau using rs and GIS

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Journal of Geographical Sciences 2002年第3期12卷 283-288页

作者： YANG Shengtian, LIU Changming, YANG Zhifeng, SUNRui, ZHOU Xiaodong(1. Inst. of Environmental Sciences, beijing Normal University, beijing 100875, China 2. Dept. of Resources and Environmental Science, beijing Normal University, beijing 100875,China) Inst. of Environmental Sciences Beijing Normal University Beijing China Dept. of Resources and Environmental Science Beijing Normal University Beijing China

The impact of interbasin water transfer on environment is very significant. The affected area of the west route scheme of the South to North Water Transfer Project in China (SNWT) is located in the eastern Tibetan Plateau, where the altitude is high with frigid eco-environment. In this article, remote sensing and GIS are applied to analyze the natural environment and the natural environment index is established to express the natural conditions of the study area. After the natural environment index is divided into four grades and the features of each grade are analysed, some results are obtained for reference in environmental assessment of the west route of SNWT.

关键词： Qinghai-Tibet Plateau environmental assessment remote sensing GIS

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用FPGA实现rs-485通信接口芯片

系统工程与电子技术 2002年第4期24卷 103-106页

作者：梁士龙王力男杨嘉伟中国航天科工集团公司二院25所北京100854 信息产业部电子54所河北石家庄050081 中国航天科工集团公司研发中心北京100830

在点对多点主从通信系统中 ,需要合适的接口形式和通信协议实现主站与各从站的信息交换。rs -4 85接口是适合这种需求的一种标准接口形式。当选择主从多点同步通信方式时 ,工作过程与帧格式符合HDLC/SDLC协议。介绍了采用VHDL语言在FPG... 详细信息

在点对多点主从通信系统中 ,需要合适的接口形式和通信协议实现主站与各从站的信息交换。rs -4 85接口是适合这种需求的一种标准接口形式。当选择主从多点同步通信方式时 ,工作过程与帧格式符合HDLC/SDLC协议。介绍了采用VHDL语言在FPGA上实现的以HDLC/SDLC协议控制为基础的rs - 4 85通信接口芯片。实验表明 ,这种接口芯片操作简单、体积小、功耗低、可靠性高 ,极具实用价值。

关键词： FPGA rs-485通信接口芯片通信系统标准接口芯片

Diffusion of Hydrogen in Amorphous NiCrFeSiB Alloy

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Journal of Materials Science & Technology 1996年第1期12卷 15-18页

作者： Zuo, Y Yang, B Xu, rs Dept. of Applied Chemistry Beijing University of Chemical Technology Beijing 100029 China

The diffusion of hydrogen in amorphous NiCrFeSiB alloy has been studied by electrochemical method. In the temperature range of 20 similar to 50 degrees C, diffusion coefficient of hydrogen in the alloy follows the equation: D(cm(2)/s) = 9.27x10(-8) exp(-53.4 kJ/RT). At room temperature the diffusion coefficient D and the solubility C-0 are 6.125 x 10(-12) cm(2)/s and 0.007 mol/cm(3), respectively. When As2O3 is added into the cathodic solution or the charging current density is increased, the diffusion coefficient and solubility increase, and the diffusion activation energy decreases. The influence of amorphous structure on diffusion and solution of hydrogen is discussed.

关键词： Nickel alloys

Comparison between phylogeny of introns and exons in primates

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Chinese Science Bulletin 1999年第21期44卷 1940-1946页

作者： Wang, N Chen, rs Chinese Acad Sci Prot Engn Lab Inst Biophys Beijing 100101 Peoples R China

Introns and exons of 7 genes ( epsilon globin, gamma-1 globin, gamma-2 globin, delta globin, beta globin, Immunoglobulin and prepro-insulin) in primates have been separated out and used to infer phylogeny respectively. For each gene, results based on these two parts have been compared and showed that: ( i ) the topology of introns is almost

关键词： phylogeny inference intron substitution rate molecular evolution.

Prevalence,intensity of infection and risk factors of urinary schistosomiasis in preschool and school aged children in Guma Local Government Area,Nigeria

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Asian Pacific Journal of Tropical Medicine 2014年第1期7卷 34-39页

作者： EU Amuta rs Houmsou Department of Biological Sciences University of Agriculture Makurdip.M.B 2373 MakurdiBenue StateNigeria. Department of Biological Sciences Taraba State UniversityJalingoP.M.B 1167 JalingoTaraba StateNigeria

Objective:To determine the prevalence and intensity of infection and the risk factors associated with urinary schistosomiasis in pre—school and school aged children in Cuma Local Government Area of Benue State,***:Urine filtration technique using polycarbonate membrane filters was employed to process urine specimens and to determine presence of Schistosoma haematobium eggs in *** were also administered to children to collect information on socio-demographic data and water-contact ***:An overall prevalence of 55.0%(165/300)was recorded out of the 300 urine samples *** of infection varied between 36.0%-64.0%with a significant difference(X^2=11.59,P=0.041)between the different communities *** were more infected(60.6%,103/170)than females(47.7%,62/130)with a significant difference(X^2=4.95,P=0.026).The age-related prevalence showed higher prevalence(70.5%,36/52)in the 11-15 year old children than that in the 1-5 year old ones(44.9%,53/118).A significant difference was observed in the prevalence between the age groups(X^2=10.56,P=0.014).The prevalence of light intensity of infection(1-49 eggs/10 mL of urine)(86.6%)was significantly higher than that of heavy intensity of infection(5=50 eggs/10 mL of urine)(13.3%)in the area(t=16.48,P=0.000).Water contact activities of the children revealed that children that were involved in irrigation and those that went swimming in water bodies were observed to be at higher risk of becoming infected with urinary schistosomiasis in the area with odd ratios(risk factors)of 2.756(1.334-5.693)and 2.366(1.131-4.948)respectively at P<0.05 ***:The study revealed the hyperendemicily of urinary schistosomiasis in the preschool and school aged children in Guma Local Government *** is therefore recommended that praziquantel should be administered to children in the area and systematic epidemiological studies should be undertaken in the whole Local Government Ar

关键词： Hyperendemic Schistosomiasis Urine Prevalence Intensity Risk factor

A new intelligent prediction system model-the compound pyramid model

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Science China(Information Sciences) 2012年第3期55卷 723-736页

作者： YANG BingRu , QU Wu, WANG LiJun & ZHOU Ying School of Information Engineering, University of Science and Technology beijing, beijing 100083, China School of Information Engineering University of Science and Technology Beijing Beijing China

A current development trend in research on intelligent systems is to optimize a general intelligent prediction system into an individuation intelligent prediction system that is applied in specialized fields. Protein structure prediction is a challenging international issue. In this paper, we propose a new intelligent prediction system model, designed as a multi-layer compound pyramid model, for predicting secondary protein structure. The model comprises four independent intelligent interfaces and several knowledge discovery methods. The model penetrates throughout the domain knowledge, with the effective attributes chosen by Causal Cellular Automata. Furthermore, a high pure structure database is constructed for training. On the rs126 dataset, the overall state per-residue accuracy, Q3, reached 83.99%, while on the CB513 dataset, Q3 reached 85.58%. Meanwhile, on the CASP8 sequences, the results are superior to those produced by other methods, such as Psipred, Jpred, APSSP2 and BehairPred. These results confirm that our method has a strong generalization ability, and that it provides a model for the construction of other intelligent systems.

关键词： knowledge discovery intelligent prediction system model compound pyramid model