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Debris Flow Hazard Assessment Based on Support Vector Machine

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Wuhan University Journal of Natural sciences 2006年第4期11卷 897-900页

作者： YUAN Lifeng 1, 2., ZHANG Youshui 3. 1. institute of Mountain Hazards and Environment, chinese Academy of {2., Chengdu 610041, Sichuan, china 2. Graduate University of chinese Academy of {2., Beijing 100049, china 3. institute of Geographical {2. and Natural Resources Research, chinese Academy of {2., Beijing 100101, china institute of Mountain Hazards and Environment Chinese Academy of Sciences Chengdu 610041 Sichuan China ***

Seven factors, including the maximum volume of once flow , occurrence frequency of debris flow , watershed area , main channel length , watershed relative height difference , valley incision density and the length ratio of sediment supplement are chosen as evaluation factors of debris flow hazard degree. Using support vector machine （SVM） theory, we selected 2.9 basic data of 3. debris flow channels in Yunnan Province as learning samples in this study. We create a debris flow hazard assessment model based on SVM. The model was validated though instance applications and showed encouraging results.

关键词： debris flow hazard assessment support vector machine (SVM)

Integrated precise orbit determination of Shenzhou IV unmanned spacecraft

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Science china(Technological sciences) 2004年第5期47卷 518-525页

作者： L Congmin1,2. GU Yidong3. LIN Baojun3.& GUO Jiong3.1. Center for Space Science and Applied Research, chinese Academy of sciences, Beijing {2., china 2. Graduate School of the chinese Academy of sciences, Beijing 10003., china 3. General Establishment of Space Science and Application, chinese Academy of sciences, Beijing {2., china Correspondence should be addressed to L Congmin General Establishment of Space Science and Application Chinese Academy of Sciences

Considering the characteristic orbit of Shenzhou IV spacecraft and the advantages and disadvantages of several types of domestic orbit measurements, a scheme of IPOD is determined, which uses GPS, SLR and USB observation data jointly plus precise ionosphere corrections to GPS observation data. IPOD system and mathematic models of OD are introduced. The results of different joint OD are analyzed using true observation data, and show that radial accuracy is better than 2.m.

关键词： Shenzhou IV unmanned spacecraft integrated precise orbit determination GPS SLR USB.

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, {3. Agricultural University, Beijing 100083. {3. 2. {2. of Physics, chinese Academy of sciences, Beijing 100080, {3. College of Science China Agricultural University Beijing China institute of Physics Chinese Academy of Sciences Beijing 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 age of the plant fossil assemblage in the Liuqu Conglomerate of southern Tibet and its tectonic significance

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Progress in Natural Science:Materials International 2006年第1期16卷 55-64页

作者： FANG Aimin1, YAN Zhen1, LIU Xiaohan2. PAN Yusheng1, LI Jiliang1, YU Liangjun1, HUANG Feixing2.and TAO Junrong3.(1.Laboratory of Lithosphere Tectonic Evolution, institute of Geology and Geophysics, {3. Academy of {2., Beijing 10002., china 2. institute of Tibet Plateau Research, {3. Academy of {2., Beijing 100085, china 3. institute of Botany, {3. A cademy of {2., Beijing 100093. china) Laboratory of Lithosphere Tectonic Evolution Institute of Geology and Geophysics Chinese Academy of Sciences Beijing 100029 China institute of Tibet Plateau Research Chinese Academy of Sciences Beijing 100085 China institute of Botany Chinese Academy of Sciences Beijing 100093 China)

The Liuqu Conglomerate, situated to the south of Yarlung Tsangbo Suture Zone (YTSZ), is a suit of molasse formed in a foreland basin of the Himalayan orogenic belt after the collision between the two plates of the Indian and Eurasion, It is of great significance in constraining the younger limit time of the collision of the two plates and providing stratigraphic evidence to reveal the post-colli sional tectonic evolution and uplifting history of the Tibet plateau. However, the age of this molasse suit and its correlation to other synchronous strata distributed in southern Tibet have been in great disputes for a long time. Especially in recent years, argues on its ages are growing violently with the recognition of the great sedimentary tectonic significances of this molasse. During the field work carried out recently on this molasse suit, a lot of plant fossils were found preserved in fairly good conditions in the upper part of this strata, which is of great help in determining its age. By identification, the assemblage of the plant fossils belongs to a tropic to subtropic flora developed in the southern margin of the Northern Hemisphere supercontinent during the Middle to Later Eocene, which can provide good constraint on its formation age. This paper is to give a brief introduction of the plant assemblage and its age, and to discuss their tectonic significances.

关键词： Liuqu conglomerate plant fossils age Eocene Tectonic implications.

Representation of microscale ocean wavenumber spectrum correct to the second order

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Science china Earth sciences 2005年第4期48卷 549-554页

作者： YUAN Yeli2.& HUA Feng1,2.3.1. institute of Oceanology, {3. Academy of {2., Qingdao 2.6071, china 2. Key Laboratory of Marine Science and Numerical Modeling, State Oceanic Administration, Qingdao 2.6061, china 3. Graduate School of the {3. Academy of {2., Beijing 10003., china Key Laboratory of Marine Science and Numerical Modeling State Oceanic Administration Qingdao China institute of Oceanology Chinese Academy of Sciences Qingdao China Graduate School of the chinese Academy of sciences Beijing China

In this paper, the analytical representations of four wave source functions in high-frequency spectrum range are given on the basis of ocean wave theory and dimensional analysis, and the perturbation method is used to solve the governing equations of ocean wave high-frequency spectrum on the basis of the temporally stationary and locally homogeneous scale relations of microscale wave. The microscale ocean wavenumber spectrum correct to the second order has an explicit structure, its first order part represents the equilibrium between dif- ferent source functions, and its second order part represents the contribution of microscale wave propagation.

关键词： temporally stationary and locally homogeneous, source function in high-frequency spectrum range, microscale ocean wavenumber spectrum.

Interannual variability of Antarctic Oscillation and its influence on East Asian climate during boreal winter and spring

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Science china Earth sciences 2006年第5期49卷 554-560页

作者： FAN Ke1,2.3.& WANG Huijun2.1. Nansen-Zhu International Research Center, institute of Atmospheric Physics, {3. Academy of {2., Beijing 10002., china 2. Department of Atmospheric Science, Yunnan University, Kunming 650091, china 3. Graduate University of the {3. Academy of {2., Beijing 100049, china Nansen-Zhu International Research Center Institute of Atmospheric Physics Chinese Academy of Sciences Beijing China Department of Atmospheric Science Yunnan University Kunming China Graduate University of the chinese Academy of sciences Beijing China

The interannual variability of Antarctic Oscillation (AAO) and its influence on East Asian climate during both boreal winter and spring are addressed. The results show that the positive AAO anomaly decreases the cold activity over East Asia during both boreal winter and spring. AAO-related barotropic meridional teleconnection from Antarctic to Arctic is found through analysis of mean me- ridional circulations. This meridional teleconnection is remarkable over Eurasia during boreal winter and over the Pacific Ocean during boreal spring. The results also show that zonal mean zonal wind at high latitudes in Southern Hemisphere has well positive correlation with that of Eurasia during boreal winter and has negative correlation with Pacific North American teleconnection (PNA) during boreal spring, which again display the meridional teleconnection. Thus, local meridional teleconnection is a possible linkage for interaction of circulations at mid-high latitudes between both hemispheres.

关键词： Antarctic Oscillation, Eurasian west wind, meridional teleconnection, mean meridional circulation.

Formal analysis and design of multi-party fair exchange protocols

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Science in china(Series F) 2006年第2期49卷 155-174页

作者： QING Sihan1,2.3.& LI Gaicheng1,3.1. Engineering Research Center for Information Security Technology, institute of Software, chinese Academy of {2., Beijing 100080, china 2. Beijing Zhongke Ansheng Corporation of Information Technology, Beijing 100080, china 3. Graduate School of the chinese Academy of {2., Beijing 10003., china Engineering Research Center for Information Security Technology Institute of Software Chinese Academy of Sciences Beijing Zhongke Ansheng Corporation of Information Technology Graduate School of the chinese Academy of sciences

Based on the origin of message items and channel combination between transacting parties, and events and relations among events, this paper presents a concise, precise, and hierarchical model for general fair exchange protocols, formally specifies various security requirements which are able to reflect inherent requirements for fair exchange protocols more rigorously, and partition these security requirements with fine granularity. This work helps analyze, debug, and design multi-party fair exchange protocols more effectively and elaborately,

关键词： fair exchange logical protocol formal model security requirement.

Analysis and application of automatic deformation monitoring data for buildings and structures of mining area

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中国有色金属学会会刊：英文版 2011年第S3期21卷 516-522页

作者： XIAO Jie1, 2. 3. ZHANG Jin4 1. institute of Geodesy and Geophysics, chinese Academy of {2., Wuhan 43.077, china 2. Key Laboratory of Dynamic Geodesy, institute of Geodesy and Geophysics, chinese Academy of {2., Wuhan 43.077, china 3. Graduate School of chinese Academy of {2., Beijing 100049, china 4. Department of Surveying and Mapping, Taiyuan University of Technology, Taiyuan 03.02., china institute of Geodesy and Geophysics Chinese Academy of Sciences Wuhan 430077 China Key Laboratory of Dynamic Geodesy Institute of Geodesy and Geophysics Chinese Academy of Sciences Wuhan 430077 China Graduate School of chinese Academy of sciences Beijing 100049 China Department of Surveying and Mapping Taiyuan University of Technology Taiyuan 030024 China

The buildings and structures of mines were monitored automatically using modern surveying technology. Through the analysis of the monitoring data, the deformation characteristics were found out from three aspects containing points, lines and regions, which play an important role in understanding the stable state of buildings and structures. The stability and deformation of monitoring points were analysed, and time-series data of monitoring points were denoised with wavelet analysis and Kalman filtering, and exponent function and periodic function were used to get the ideal deformation trend model of monitoring points. Through calculating the monitoring data obtained, analyzing the deformation trend, and cognizing the deformation regularity, it can better service mine safety production and decision-making.

关键词： wavelet analysis Kalman filtering deformation monitoring data analysis mine

Mass Spectrometric Evidence of Heparin Disaccharides for the Catalytic Characterization of A Novel Endolytic Heparinase

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Acta Biochimica et Biophysica Sinica 2004年第12期36卷 840-844页

作者： Yapeng CHAO1,3. Shaoxiang XIONG2. Xiulan CHENG1, and Shijun QIAN1* 1institute of Microbiology, chinese Academy of {2., Beijing 100080, china 2.enter of Mass Spectrometry, institute of chemistry, chinese Academy of {2., Beijing 100080, china 3.raduate School of the chinese Academy of {2., Beijing 10003., china institute of Microbiology Chinese Academy of SciencesBeijing 100080 China Graduate School of the chinese Academy of sciencesBeijing 10003. China Center of Mass Spectrometry Institute of Chemistry Chinese Academy of SciencesBeijing 100080 China

Heparinase from different sources can eliminate heparin or/and heparan sulfate into various low-molecular weight heparins with different characteristics. Porcine intestinal mucosa heparin was de- graded into a series of oligosaccharides by a novel heparinase from the species Sphingobacterium. Disaccha- ride components from the digests were separated and purified by ultrafiltration and HPLC. Five major peaks appeared as three types according to their retention time. The mass spectrometry of peak I mainly gave the non-sulfated disaccharide with the mass of 3.9 Da. Peak II and III were indicated as two major monosulfated disaccharides with molecular mass of 417 and 459 Da respectively. Moreover, the peak III represented an N- acetyl disaccharide. Both peak IV and V showed the same mass of 496 Da, hinting that they were disulfate- substituted disaccharides. No trisulfate-substituted disaccharides were detected in the mixture of the heparin digest though they were abundant in the heparin structure. The results revealed that the heparinase might specifically cut the sites with low sulfated domain in heparin.

关键词： electrospray ionization-mass spectrometry heparin disaccharides heparinase high perfor- mance liquid chromatography Sphingobacterium sp.