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3D building modeling,organization and application in digital city system

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中国科学：技术科学英文版 2010年第S1期53卷 134-142页

作者： YANG Xue 1,WENG JingNong 1,2.XIA YuBin 2.WU Lun 3 & SUI ZhengWei 3 1 college of software,{2.,Beijing 100191,china 2.college of Computer,{2.,Beijing 100191,china 3 Institute of Remote Sensing and GIS,Peking university,Beijing 100871,china beihang Univ Coll Software Beijing 100191 Peoples R China beihang Univ Coll Comp Beijing 100191 Peoples R China Peking Univ Inst Remote Sensing & GIS Beijing 100871 Peoples R China

The real world is a three-dimensional(3D)space requiring that 3D geospatial information applications be developed in alignment with the observer’s visual and perceptive ***,3D building model data are required in a wide range of areas such as urban planning,environmental protection,real estate management and emergency *** the same time,the development of Web service[LU1]technologies allows the possibility of the widely distributed 3D geospatial data on the web.3D city building model with its related information is an important part in the construction of a digital city system,and has become a staple resource on the web *** view of the hierarchical representation of a 3D building model,an abstract of a 3D building model based on structure details is studied,and a novel representation approach named 3D transparent building hierarchical model is presented in this *** approach fully uses both the existing 3D modeling technologies and CAD constructing mapping *** the spatial relationship description,structural components inside a building can be represented and integrated as hierarchical models in a unified 3D *** addition,based on the characteristics of the 3D building model data,a service-oriented architecture and Web service technologies for 3D city building models are *** aim of the approach is that 3D city building models can be used as a kind of data resource service on the web,and can also exist independently in various different web applications.

关键词： 3D modeling 3D transparent building hierarchical models china Star web services

Probabilistic composition of cone-based cardinal direction relations

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Science china(Technological Sciences) 2008年第S1期51卷 81-90页

作者： LIU Yu1,TIAN Yuan1 & WENG JingNong2.1 Institute of Remote Sensing and Geographical Information Systems,Peking university,Beijing 100871,china {2.,beihang university,Beijing 100083,china Peking Univ Inst Remote Sensing & Geog Informat Syst Beijing 100871 Peoples R China beihang Univ Coll Software Beijing 100083 Peoples R China

Composition tables play a significant role in qualitative spatial reasoning (QSR). At present,a couple of composition tables focusing on various spatial relations have been developed in a qualitative approach. However,the spatial reasoning proc-esses are usually not purely qualitative in everyday life,where probability is one important issue that should be considered. In this paper,the probabilistic compo-sitions of cone-based cardinal direction relations (CDR) are discussed and esti-mated by making some assumptions. Consequently,the form of composition result turns to be {(R1,P1),(R2.P2.,…,(Rn,Pn)},where Pi is the probability associated with relation Ri. Employing the area integral method,the probabilities in each composi-tion case can be computed with the assumption that the target object is uniformly distributed in the corresponding cone regions.

关键词： spatial reasoning cardinal direction relations probabilistic composition

On 3D simulation of moving objects in a digital earth system

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Science china(Technological Sciences) 2008年第S2期51卷 123-132页

作者： WENG JingNong1,WU Lun2.HUANG Jian1,WANG Yang1,YANG Xue1 & HU Bin1 1 college of software,{2.,Beijing 100191,china 2.Institute of Geographical Information System and Remote Sensing,Peking university,Beijing 100871,china college of software Beihang University Beijing 100191 China Institute of Geographical Information System and Remote Sensing Peking University Beijing 100871 China

"How do the rescue helicopters find out an optimized path to arrive at the site of a disaster as soon as possible?" or "How are the flight procedures over mountains and plateaus simulated?" and so *** this paper a script language on spatial moving objects is presented by abstracting 3D spatial moving objects' behavior when implementing moving objects simulation in 3D digital Earth scene,which is based on a platform of digital china named "chinaStar".The definition of this script language,its morphology and syntax,its compiling and mediate language generating,and the behavior and state control of spatial moving objects are discussed *** addition,the language's applications and implementation are also discussed.

关键词： Digital Earth chinaStar moving object script language

Efficient visualization techniques for high resolution remotely sensed data in a network environment

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Science china(Technological Sciences) 2008年第S1期51卷 124-134页

作者： WENG JingNong1,WU Lun2.HUANG Jian1,XIA YuBin3 & CAI Heng1 1 college of software,{2.,Beijing 100083,china 2.Institute of Geographical Information System and Remote Sensing,Peking university,Beijing 100871,china 3 college of Computer,{2.,Beijing 100083,china 1. college of software Beihang University Beijing 100083 China2. Institute of Geographical Information System and Remote Sensing Peking University Beijing 100871 China3. College of Computer Beihang University Beijing 100083 China

There are three major research hotspots in efficient visualization techniques of high resolution remotely sensed data in network environment: the data organiza-tion and access in disk storage,the image data stitching and fitting methods,and the network transfers and access. In this paper a new method of "Big File" organi-zation for improving the storage access efficiency of high resolution remote data is presented; a "virtual data source" concept is introduced to solve the stitching problem of remotely sensed data from different sources with different resolutions; a remotely sensed data access engine design based on ATL technique is discussed to process the network transfers and access of remotely sensed data. All these techniques have been adopted in a prototype of digital china named "chinaStar".

关键词： high resolution remotely sensed data spatial index pyramid model LOD Big File

Mitochondrial DNA analysis of ancient Sampula population in Xinjiang

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Progress in Natural Science:Materials International 2007年第8期17卷 927-933页

作者： Xie Chengzhi~(1,2. Li Chunxiang~2.Cui Yinqiu~(1,2. Cai Dawei~(1,2. Wang Haijing~2.Zhu Hong~1 Zhou Hui~(1,2.*) (1.Research Center for Chinese Frontier Archaeology,Jilin university,Changchun 130012.china {2. of Life Science,Jilin university,Changchun 13002.,china) [a]Research Center for Chinese Frontier Archaeology Jilin University Changchun China [b]college of Life Science Jilin University Changchun China

The archaeological site of Sampula cemetery was located about 14 km to the southwest of the Luo County in Xinjiang Khotan,china,belonging to the ancient Yutian kingdom.14C analysis showed that this cemetery was used from 2.7 *** 2.3 A.D. Ancient DNA was analyzed by 364 bp of the mitochondrial DNA hypervariable region I （mtDNA HVR-I）,and by six restriction fragment length polymorphism （RFLP） sites of mtDNA coding *** successfully extracted and sequenced intact stretches of maternally inher- ited mtDNA from 13 out of 16 ancient Sampula *** analysis of mtDNA haplogroup distribution showed that the ancient Sampula was a complex population with both European and Asian *** joining network of U3 sub-haplogroup and multi-dimen- sional scaling analysis all showed that the ancient Sampula had maternal relationship with Ossetian and Iranian.

关键词： ancient DNA mitochondrial DNA Sampula ancient populations

Optimization of thermomechanical processes in Cu-Cr-Zr lead frame alloy using neural networks and genetic algorithms

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Science china(Technological Sciences) 2005年第5期48卷 510-520页

作者： SU Juanhua1,2. LIU Ping2. DONG Qiming2.& LI Hejun1 1. college of Materials Science and Engineering, Northwestern Polytechnical university, Xi’an 710072. {2. 2. college of Materials Science and Engineering, Henan university of Science and Technology, Luoyang 471003, {2. 1. college of Materials Science and Engineering Northwestern Polytechnical University 710072 Xi’an China 2. college of Materials Science and Engineering Henan University of Science and Technology 471003 Luoyang China

The thermomechanical treatment process is effective in enhancing the properties of the lead frame copper alloy. In this study, an optimal pattern of the thermomechanical processes for Cu-Cr-Zr was investegated using an intelligent control technique consisting of neural networks and genetic algorithms. The input parameters of the artificial neural network (ANN) are the reduction ratio of cold rolling, aging temperature and aging time. The outputs of the ANN model are the two most important properties of hardness and conductivity. Based on the successfully trained ANN model, genetic algorithms (GA) are used to optimize the input parameters of the model and select perfect combinations of thermomechanical processing parameters and properties. The good generalization performance and optimized results of the integrated model are achieved.

关键词： Cu-Cr-Zr alloy, thermomechanical processing optimization, artificial neural network, genetic algorithms.

Solution of a hollow thick-wall cylinder subject to quadric function pressures and its limit when l→∞

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Science china(Technological Sciences) 2004年第2期47卷 229-236页

作者： LIU Zhubai1,SHAN Rui2.LIU Wen2.& NI Liyong1 1.college of Mechanical Engineering,Yanshan university,Qinhuangdao 066004,{2. 2.college of Science,Yanshan university,Qinhuangdao 066004,{2. 1. college of Mechanical Engineering Yanshan University 066004 Qinhuangdao China 2. college of Science Yanshan University 066004 Qinhuangdao China

The problem of a hollow thick-wall cylinder subject to quadric function pressures is solved with a new stress function, thus laying the basis for solving the spatial symmetric deformation of a hollow cylinder subject ... 详细信息

关键词： quadric function pressure, analytic solution, stress function, hollow cylinder.

Pattern phenomena in an rf discharge dusty plasma system

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Science china(Physics,Mechanics & Astronomy) 2006年第5期49卷 588-596页

作者： HUANG Feng1,2. YE Maofu2.& WANG Long2.1. college of Science, china Agricultural {2., Beijing 100083, china 2. Institute of Physics, Chinese Academy of Sciences, Beijing 100080, china 1. college of Science China Agricultural University Beijing 100083 China 2. Institute of Physics Chinese Academy of Sciences Beijing 100080 China

Various dust patterns are observed in an rf discharge dusty plasma system. According to the dust growth process from small to large in size, the formation of different dust patterns can be divided into two stages: the small-particle stage (or dust cloud stage), and the large-particle stage (or dust crystal stage). The evolution relations between different dust patterns with gas pressure changing are investigated. Dust voids, dust acoustic waves and strong turbulence modes are presented at the small-particle stage. The self-organized dust lattices and dust clusters are investigated at the large-particle stage. The static structure of a dust lattice is characterized by means of the pair correlation function. Dust clusters formed by particles with different numbers and the regular evolution of the clusters with gas pressure are also investigated. The packing sequences of dust clusters are verified through two-dimensional confined molecular dynamics simulations.

关键词： dusty plasma dust patterns

The tri-band high spectral resolution spectrometer with gratings in tandem for the charge-exchange recombination spectroscopy diagnostic system on HL-2. tokamak

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Plasma Science and Technology 2024年第6期26卷 103-110页

作者：刘亮余德良马倩何小斐 Maarten DE BOCK Manfred von HELLERMANN Michael WALSH 陈文锦何小雪魏彦玲张能李栋魏会领 the HL-2. Team Southwestern Institute of Physics Chengdu 610041People’s Republic of China college of Physics and Optoelectronic Technology Baoji University of Arts and SciencesBaoji 721000People’s Republic of China ITER Organization Route de Vinon-sur-VerdonCS 90046St.Paul Lez Durance Cedex 13067France Fusion Spectroscopy Markgraf-Albrecht Str.14Berlin 10711Germany

Charge-exchange(CX) recombination spectroscopy is a powerful tool monitoring ion temperature and plasma rotation with good temporal and spatial resolutions. A compact, new design for a high-throughput, tri-band high spectral resolution spectrometer has been developed for the charge-exchange recombination spectroscopy measurement on the HL-2. tokamak. The simultaneous measurements of He II(468.57 nm), C VI(52..1 nm), and Dα(656.1 nm accompanied by beam emission spectra) with an acquisition frequency up to 400 Hz are achieved by vertically binning the spectrum from each fiber in experiments. Initial results indicate that the system can provide radial profiles of not only ion temperature and rotation velocity,but also concentration of carbon. For the case of helium, the measurements for the ion temperature and rotation velocity are straightforward but the apparent concentration associated with the observed CX intensity is obviously too high. Modeling of the active He II CX feature including plume contributions needs to be carried out to extract the true helium *** spectrometer could become a prototype for the ITER charge-exchange recombination spectroscopy diagnostic and the pilot experiments, as presented here, demonstrate the possibility of impurity concentrations measurements based on the combined measurement of local beam emission and charge-exchange recombination spectroscopy spectra.

关键词： CXRS ion temperature plasma rotation impurity concentration