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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 sciences, Chengdu 61004., Sichuan, China 2. Graduate University of chinese academy of sciences, {3. 10004., China 3. institute of Geographical sciences and Natural Resources Research, chinese academy of sciences, {3. 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 259 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)

U-Pb dating of zircon from the bed parallel anatectic granitic intrusion in the Baoban group in Hainan Island and the tectonic implication

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Science China Earth sciences 2005年第12期48卷 2092-2103页

作者： DING Shijiang1, HU Jianmin2, SONG Biao3.4. CHEN Mulun1, XIE Shengzhou1 & FAN Yuan1 1. Geological Surveying institute of Hainan, Haikou 570206, China 2. institute of Geomechanics, chinese {3. of Geological {4., beijing 100081, China 3. beijing Center of SHRIMP, beijing 10003., China 4. institute of Geology, chinese {3. of Geological {4., beijing 10003., China Geological Surveying institute of Hainan Haikou China institute of Geomechanics Chinese Academy of Geological Sciences Beijing China beijing Center of SHRIMP Beijing China institute of Geology Chinese Academy of Geological Sciences Beijing China

The petrological and geochemical features of the bed parallel granitic intrusion in the Pre-Cambrian Baoban group in Hainan Island attest to the anatexis origin of the granites. U-Pb dating analyses of zircons from the anatectic granite and the biotite two-feldspar gneiss in the Baoban group, using SHRIMP II in the beijing Ion-probe Center, acquire 206Pb/23.U ages of 3.8±3.5 Ma (of granite, 95% confidence level, MSDW=1.23. and 3.2.9±6.1 Ma (of gneiss, 95% confidence level, MSDW = 2.04. respectively. The two late Devonian ages indicate consistently a tectonic- thermal event experienced in Hainan Island, and are the first discovered record of the Devonian geological process in the district. This event possibly resulted from the deep ther-mal-dynamic process when the Gondwana continent began to break up in the Devonian period.

关键词： Hainan Island, Devonian period, anatectic granite, zircon SHRIMP U-Pb dating.

Role of plasminogen activators and inhibitors in reproduction

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chinese Science Bulletin 1999年第8期44卷 673-685页

作者： LIU YixunState Key Laboratory of Reproductive Biology, institute of Zoology , chinese academy of sciences , beijing 100080, China State Key Laboratory of Reproductive Biology Institute of Zoology Chinese Academy of Sciences Beijing China

The recent progress in the studies on the role of local and directed fibrinolysis controlled by plasminogen activators (PAs) and regulated by their inhibitors (PAIs) in reproduction is summarized. Hormone-induced coordinated expression of tissue type PA (tPA) and PAI type-1 (PAI-1) in the ovary is involved in the processes of ovulation and luteal regression; increases in urokinase type PA (uPA) and PAI-1 activity in the early stage of luteinized follicles may be responsible for ovarian tissue remodeling and angiogenesis; the PA system has been found to play an important role in spermatogenesis in testis and modulation of sperm maturation in epididymis. PA and matrix matalloproteanase (MMP) and their respective inhibitors have also been identified in trophoblast and uterus. The targeted proteolytic activity generated by the two systems may play an essential role in the processes of the cyclic uterine angiogenesis, implantation and pla-centation as well as parturition.

关键词： plasminogen activator and inhibitor follicle rupture luteolysis angiogenesis spermatogenesis placentation.

Numerical simulation of Richtmyer-Meshkov instability

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Science China Mathematics 2004年第z1期47卷 234-244页

作者： FU Dexun, MA Yanwen, ZHANG Linbo & TIAN BaolinState Key Laboratory of Nonlinear Mechanics, institute of Mechanics, chinese academy of sciences, beijing 100080, China State Key Laboratory of Scientific and Engineering Computing, institute of Computational Mathematics, chinese academy of sciences, beijing 100080, China State Key Laboratory of Nonlinear Mechanics Institute of Mechanics Chinese Academy of Sciences Beijing China State Key Laboratory of Scientific and Engineering Computing Institute of Computational Mathematics Chinese Academy of Sciences Beijing China

The compressible Navier-Stokes equations discretized with a fourth order accurate compact finite difference scheme with group velocity control are used to simulate the Richtmyer-Meshkov (R-M) instability problem produced by cylindrical shock-cylindrical material interface with shock Mach number Ms=1.2 and density ratio 1:20 (interior density/outer density). Effect of shock refraction, reflection, interaction of the reflected shock with the material interface, and effect of initial perturbation modes on R-M instability are investigated numerically. It is noted that the shock refraction is a main physical mechanism of the initial phase changing of the material surface. The multiple interactions of the reflected shock from the origin with the interface and the R-M instability near the material interface are the reason for formation of the spike-bubble structures. Different viscosities lead to different spike-bubble structure characteristics. The vortex pairing phenomenon is found in the initial double mode simulation. The mode interaction is the main factor of small structures production near the interface.

关键词： R-M instability, direct numerical simulation, shock-interface interaction.

THERMALLY STIMULATED SHAPE MEMORY BEHAVIOR OF POLYMERS WITH PHYSICAL CROSSLINKS

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chinese Journal of Polymer Science 1999年第3期17卷 203-213页

作者： Mao Xu Feng-kui Li Polymer Physics Laboratory, institute of Chemistry, chinese academy of sciences, beijing 100080, China 中科院化学所高分子物理及化学国家重点实验室北京 100080 中科院化学所高分子物理及化学国家重点实验室北京

The shape memory effect of polymers was investigated for the purpose of improving the processing conditions of their preparation and broadening the list of polymers for shape memory applications. Emphasis was put on the possibility of using polymers with physical crosslinks as shape memory materials and their structure-function relationships. Segmented block polyurethanes and polyethylene/nylon 6 graft copolymers were used as examples of polymers with physical crosslinks. It was found that these copolymers can really be used as thermally stimulated shape memory materials with large recoverable strain and high final recovery rate. The main advantage of using copolymers is their improved processing conditions as compared with polymers with chemical crosslinks. As only physical crosslinks are introduced, all conventional processing techniques for thermal plastics can be used, and the materials become easily reusable. The results indicate that the high crystallinity of these copolymers at room temperature and the formation of stable physical crosslinks are the two prerequisites for these polymers to exhibit shape memory effect. The successful use of block and graft copolymers imply the possibility of using polymers of various structure and properties as shape memory materials.

关键词： shape memory effect segmented polyurethanes polyethylene nylon graft copolymers

One-dimensional unsteady general solution for Wang bioheat transfer equation with heat source proportional to temperature

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Progress in Natural Science:Materials International 2006年第7期16卷 766-768页

作者： GOU Chenhua and CAI Ruixian ( institute of Engineering Thermophysics, chinese academy of sciences, beijing 100080, China Graduate School, chinese academy of sciences, beijing 100080, China) chinese Acad Sci Inst Engn Thermophys Beijing 100080 Peoples R China chinese Acad Sci Grad Sch Beijing 100080 Peoples R China

An analytical general solution is derived for the non-Fourier Wang bioheat transfer model with special internal heat production. It is valuable for finding the special solutions with specified conditions and for expanding the understanding of the non-Fourier heat conduction phenomena in living tissues, for example, the controversial temperature fluctuation effects. This analytical solution can also be used as the benchmark solution to check the numerical calculations and to develop various numerical computational approaches. Because there is an arbitrary function in the expression of internal heat production, this solution can actually be applied to many types of internal heat production distributions.

关键词： bioheat transfer model non-fourier effect analytical solution

THERMODYNAMIC STUDY OF CHROMITE CAUSTIC FUSION PROCESS

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Acta Metallurgica Sinica(English Letters) 2001年第1期14卷 47-55页

作者： S.L. Zheng and Y. Zhang (institute of Chemical Metallurgy, the chinese academy of sciences, beijing 100080, China) institute of Chemical Metallurgy the Chinese Academy of Sciences

A new method for chromate cleaning production, named chromite caustic fusion process, is advanced by institute of Chemical Metallurgy, the chinese academy of sciences. With sodium hydroxide as reaction medium, the new process is composed of three procedures: liquid phase oxidation of chromite, metastable phase separation and carbonation ammonium transition. Generally illustrating the new process and its features, this paper mainly studies the thermodynamics of chromite oxidation. The new process has much better practical results than the conventional chromate production process in which sodium carbonate is used as reaction medium. The superiority is also shown through thermodynamic studies.

关键词： Melting Oxidation Recycling Sodium compounds Thermodynamics

OsFKBP1 interacts with phytochrome B in rice

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Progress in Natural Science:Materials International 2009年第11期19卷 1523-1528页

作者： Suhai Gu,Fang Zhang,Naihu Wu~* institute of Genetics and Developmental Biology,chinese academy of {3.,3.Zhongguancunnanyitiao,{4. 100080,China institute of Genetics and Developmental Biology Chinese Academy of Sciences 3 Zhongguancunnanyitiao Beijing 100080 China

Part of the C-terminal of rice phytochrome B was used as bait to screen a cDNA library constructed from young rice panicles in a yeast two-hybrid screening.A positive clone was selected,and the sequence was characterized as encoding a FKBP protein,which is a putative developmental *** in vitro pull-down assay using recombinant proteins and analysis of bimolecular fluorescence complementation in onion epidermal cells indicated that two proteins interact in vitro and in *** results of reverse transcription polymerase chain reaction showed that two genes were co-expressed in the examined rice organs,suggesting that OsFKBP1 may play a role in light signal transduction in rice.

关键词： Rice Yeast two hybrid Phytochrome BiFC

Influence of curved interfaces of phase change on the radial segregation of crystal growth

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chinese Science Bulletin 1997年第7期42卷 601-605页

作者： HU Wenruiinstitute of Mechanics, chinese academy of sciences, beijing 100080, China institute of Mechanics Chinese Academy of Sciences Heijing China

THE radial uniformity of components is an important parameter for crystal growth of a semiconductor of binary alloy. Radial segregation may be influenced by many factors, such as the convection, curved solidification ... 详细信息

关键词： microgravity science crystal growth diffusion process.