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Impact of land-use change on hydrological processes in the Maying River basin, china

Science china Earth Sciences 2006年第10期49卷 1098-1110页

作者： WANG Genxu1,3. ZHANG Yu2, LIU Guimin2 & CHEN Lin3.1. Institute of Mountain Hazards and Environment, Chinese Academy of Sciences, Chengdu 610041, china 2. Cold and Arid Regions Environmental and Engineering Research Institute, Chinese Academy of Sciences, Lanzhou 73.000, china 3. Resource and Environment school, Lanzhou University, Lanzhou 73.000, china Institute of Mountain Hazards and Environment Chinese Academy of Sciences Chengdu China Resource and Environment school Lanzhou University Lanzhou China Cold and Arid Regions Environmental and Engineering Research Institute Chinese Academy of Sciences Lanzhou China

Since the 1960s, dramatic changes have taken place in land-use patterns characterized by the persistent expansion of cultivated land and a continuous decrease in natural woodland and grassland in the arid inland river basins of china. It is very important to assess the effects of such land-use changes on the hydrological processes so vital for water resource management and sustainable development on the catchment scale. The Maying River catchment, a typical arid inland watershed located in the middle of the Hexi Corridor in northwest china, was the site chosen to investigate the hydrological responses to land-use changes. The annual runoff, base flow, maximum peak flow, and typical seasonal runoff in both spring and autumn flood periods were selected as the variables in the hydrological processes. Statistical-trend analysis and curvilinear regression were utilized to detect the trends in hydrological variables while eliminating the climatic influence. The relationship between cultivated land-use and hydrological variables was analyzed based on four periods of land-use variation data collected since 1965. A runoff model was established composed of two factors, i.e., cultivated land use and precipitation. The impact of land use changes, especially in the large ar- eas of upstream woodland and grassland turned into cultivated lands since 1967, has resulted in a mean annual runoff decrease of 28.12%, a base flow decline of 3..3.%, a drop in the maximum peak discharge of 3..77%, and mean discharge decreases in spring and autumn of 3..05% and 24.87% respectively, of which the contribution of cultivated land expansion to the influence of annual runoff amounts to 77%-80%, with the contribution to the influence of spring discharge being 73.-81%, and that to the influence of base flow reaching 62%-65%. Thus, a rational regulation policy of land use patterns is vitally important to the sustainable use of water resources and the proper development of the entire catchment.

关键词： land-use change, arid inland river catchment, hydrological process, impact, Maying River.

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COLLECTIVELY COMPACT COMPOSITION OPERATOR SEQUENCES BETWEEN BERGMAN AND HARDY SPACES

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Acta Mathematica Scientia 2004年第2期24卷 206-212页

作者：王茂发刘培德 schoolofMathematicsandStatistics WuhanUniversityWuhan430072China

This paper studies the collective compactness of composition operator sequences between the Bergman and Hardy spaces. Some sufficient and necessary conditions involving the generalized Nevanlinna counting functions fo... 详细信息

关键词： Bergman space Hardy space composition operator collectively compact operator sequence

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Characteristics and origins of primary fluids and noble gases in mantle-derived minerals from the Yishu area,Shandong Province,china

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Science china Earth Sciences 2006年第1期49卷 77-87页

作者： MA Jinlong1,2, TAO Mingxin2,3.& YE Xianren2 1. Resources and Environmental school, Lanzhou University, Lanzhou 73.000, china 2. Key Laboratory of Gas Geochemistry, Institute of Geology and Geophysics, Chinese Academy of Sciences, Lanzhou 73.000, china 3. College of Resources Science & Technology, Beijing Normal University, Beijing 100875, china Resources and Environmental school Lanzhou University Lanzhou China Key Laboratory of Gas Geochemistry Institute of Geology and Geophysics Chinese Academy of Sciences Lanzhou China College of Resources Science & Technology Beijing Normal University Beijing China

Fluids and noble gases of mantle-derived materials are important tracers forthe mantle information. Compositions of primary fluids and noble gases in mantle-derived mineralsfrom the Yishu area, Shandong Province, china, were tested by the methods of heat-bursting andheat-melting respectively. The fluids are mainly composed of CO_2, CO and H_2, which account forabout 90% of the total, and are similar to the mantle-derived rocks from other areas of easternchina; ratios of ~3.e/~4He in almost all samples range from 0.82 Ra to 2.74 Ra, whereas^(40)Ar/^(3.)Ar from 299.5 to 758.8. Both ranges are much lower than those of the typical oceanmantle-derived samples (such as MORB) and primarily reflect the influences of the atmosphericcomponents and the radiogenic isotopes. Ratios of C/~3.e range from 27.6 x 10~9 to 1050 x 10~9,N_2/Ar from 927 to 56612, and N_2/~3.e from 2.5 x 10~9 to 27 x 10~9, similar to those in westernUnited States and New Zealand which belong to the tectonic plate collision regions. The ratios fallin the intersect of mantle-crust-atmosphere in the comprehensive tracer-charts, reflecting theinfluences of the atmosphere and the crusts with organic components. Our results suggest that thecomposition of the primary fluids and the isotopic ratios of the noble gases may either reflect theevolution process of mantle-derived rocks connected with the rise and eruption of magma, or theinfluence of the ancient subduction-plate on the continental mantle of this region.

关键词： noble gases, primary fluids, mantle-derived minerals, Yishu area.

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Test of magnetic susceptibility and grain-size age models of loess

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Progress in Natural Science:Materials International 2007年第11期17卷 1312-1317页

作者： Chen Yimeng1,2,3. Feng Zhaodong4 and Gong Huili1,2(1. MOE and Key Laboratory of Resources Environment and GIS of Beijing, Beijing 10003., china 2. Key Laboratory of 3. information Acquisition and Application, The Capital Normal University, Beijing 10003., china 3. Department of Economics & management of Huizhou University, Huizhou 516007, china 4. Key Laboratory of Western china’s Environmental Systems, Ministry of Education, Lanzhou University, Lanzhou 73.000, china) Key Laboratory of Resources Environment and GIS of Beijing Beijing 100037 China Key Laboratory of 3. information Acquisition and Application Capital Normal University Beijing 100037 China Department of Economics and management Huizhou University Huizhou 516007 China Key Laboratory of Western china's Environmental Systems Lanzhou University Lanzhou 730000 China

Ages of the stratigraphic boundary MIS1/2 and MIS3.4 of the Yuanbu loess section in Linxia are used as the basis of the nodal control age. The age of MIS1/2 and MIS3.4 are obtained from the latest international research result—the climatic events recorded in the stalagmite in the Hulu Cave in Nanjing, that MIS1/2 is 11.5 kaB.P. and MIS3.4 is 59.8 kaB.P.. The ages of the two climatic events contain three nodal age control models (Model 1: 0 kaB.P.—59.8 kaB.P.; Model 2: 0 kaB.P.—11.5 kaB.P. and 11.5 kaB.P.—59.8 kaB.P.; Model 3. 11.5 kaB.P.—59.8 kaB.P.), which are used as the nodal control age separately. The deposition times of various stratigraphic horizons are calculated by using the magnetic susceptibility age model and grain-size age model, and then compared with each other. In addition, the AMS14C age, OSL age and the ages of YD and H events are compared with the ages of the corresponding horizons calculated by the three models of nodal control ages. From the analyses of lithologic characters and climatic stages it has been found that both the magnetic susceptibility age model and the grain-size age model have some defects. Because the accurate control ages are selected as the nodal points of the glacial period or interglacial period, the stratigraphic deposition times determined by the high resolution of magnetic susceptibility age model and grain-size age model approximate to the actual ages. As for the relative accuracy of the two age models, the magnetic susceptibility age model is more accurate than the grain-size age model.

关键词： loess nodal control age magnetic susceptibility age model grain-size age model test

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Prediction of Tumor Outcome Based on Gene Expression Data

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Wuhan University Journal of Natural Sciences 2004年第2期9卷 177-182页

作者： Liu Juan 1,2, Hitoshi Iba 3.1. school of Computer, Wuhan University, Wuhan 43.072, Hubei, china 2. State Key Laboratory of Software Engineering, Wuhan 43.072, Hubei, china 3. Department of Frontier Informatics, University of Tokyo, Tokyo 113.8656, Japan school of Computer Wuhan University Wuhan Hubei China State Key Laboratory of Software Engineering Wuhan Hubei China Department of Frontier Informatics University of Tokyo Tokyo Japan

Gene expression microarray data can be used to classify tumor types. We proposed a new procedure to classify human tumor samples based on microarray gene expressions by using a hybrid supervised learning method called MOEA+WV (Multi-Objective Evolutionary Algorithm+Weighted Voting). MOEA is used to search for a relatively few subsets of informative genes from the high-dimensional gene space, and WV is used as a classification tool. This new method has been applied to predicate the subtypes of lymphoma and outcomes of medulloblastoma. The results are relatively accurate and meaningful compared to those from other methods. Key words bioinformatics - tumor classification - Pareto optimization - MOEA CLC number Q 786 - TP 181 Foundation item: Supported by the National Natural Science Foundation of china (603.1009), the Foundation of Young Scholars of Ministry of Education of china (150118) and Chenguang Project of Wuhan City (211121009).Biography: Liu Juan (1970-), female, Associate Professor, Postdoctoral, research direction: bioinformatics, data mining, machine learning.

关键词： bioinformatics tumor classification Pareto optimization MOEA

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Cloning and expression of putative ethylene receptor genes in soybean plant

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Progress in Natural Science:Materials International 2007年第10期17卷 1152-1160页

作者： Xie Zongming1,2,3. Lei Gang1,2, Wuriyanghan Hada1,2, Tian Aiguo1, Zhang Jinsong1 and Chen Shouyi1(1. National Key Laboratory of Plant Genomics, Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, Beijing 100101, china 2. Graduate school of Chinese Academy of Sciences, Beijing 10003., china 3. Xinjiang Academy of Agricultural and Reclamation Science, Shihezi 83.000, china) National Key Laboratory of Plant Genomics Institute of Genetics and Developmental Biology Chinese Acad. of Sci. Beijing 100101 China Graduate school Chinese Acad. of Sci. Beijing 100039 China Xinjiang Academy of Agricultural and Reclamation Science Shihezi 832000 China

Ethylene plays important roles in plant growth, development, and stress responses, and ethylene receptors have been identified and studied extensively in various plant species. Here we report the cloning of four ethylene receptor genes from soybean, i.e. GmETR1, GmERS1, GmETR2 and GmEIN4. Construction of the phylogenic tree showed that GmETR1 and GmERS1 belong to subfamily I whereas GmETR2 and GmEIN4 belong to subfamily II. The four ethylene receptor genes showed different tissue-specific expression patterns in roots, stems, leaves, cotyledons, flowers, pods and seeds of soybean. These genes were differentially regulated by various abiotic stresses and plant hormones. The possible roles of the four genes in soybean plant were also discussed.

关键词： abiotic stress expression analysis ethylene receptor plant hormone soybean.

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Research on Methods of Ecological Security Assessment of the Middle and Lower Reaches of Liaohe River Based on GIS

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Chinese Journal of Population,Resources and Environment 2005年第4期3卷 20-25页

作者： Wang Geng 1,2 , Nie Baochi 3. Wang Lin 1 & Wu Wei 1 1. school of Environmental and Biological Science and Technology, Dalian University of Technology, Dalian 116024, china 2. Urban and Environmental school, Liaoning Normal University, Dalian 116029, china 3. Shenyang Buraue of Water Resources, Shenyang 110013. china. school of Environmental and Biological Science and Technology Oalian University of Technology Oalian 116024 China Urban and Environmental school Uaoning Nonnal University Oalian 116029 China Shenyang Buraue of Water Resources Shenyang 110013 China

Ecological security assessment and early warning research possess the attributes of spatiality, non-linearity and randomicity, so we must process much spatial information. Spatial analysis and data management are the advantages of GIS, which can define distribution trend and spatial relations of environmental factors, and show ecological security pattern graphically. Spatial differences of ecological security assessment based on GIS are discussed in this paper, of which the middle and lower reaches of the Liaohe River is taken as a study case. First, to work out pressure-state-response (P-S-R) assessment indicators system, and investigate in person and gather information; second, to digitize the watershed; third, to quantize and calculate by the fuzzy method; last, to construct GIS grid database, and expound spatial differences of ecological security by GIS interpolation and assembly analysis.

关键词： the middle and lower reaches of the Liaohe River ecological security assessment indicators system GIS spatial differences

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Thermodynamic Analysis of the Preparation Process of EB-PVD SiC Coating

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Journal of Wuhan University of Technology(Materials Science) 2009年第3期24卷 363-366页

作者：易剑 school of Mechatronics Engineering Taizhou University Laser Processing Center Tianjin Polytechnic University Center for Composite Materials Harbin Institute of Technology

The process of preparing SiC coating by electron beam-physical vapor deposition （EB-PVD） was discussed from viewpoint of thermodynamis. Results show that within the temperature range of 2 700-3.3.0 K, the ratio of SiC in the SiC coating doesn＇t change much and keeps around 0.7. Purity of the as-deposited SiC coating is not high. To improve the purity of the SiC coating, the SiC ingot is required to not be, necessary in full density but be fine-grained.

关键词： thermodynamics SiC coating EB-PVD ratio of SiC purity

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Key technology of mine underground mobile positioning based on LiDAR and coded sequence pattern

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中国有色金属学会会刊：英文版 2011年第S3期21卷 570-576页

作者： WANG Zhi1, 2, WU Li-xin1, 2, LI Hui-ying3.1. College of Resources and Civil Engineering, Northeastern University, Shenyang 110004, china 2. Academy of Disaster Reduction and Emergency management, Ministry of Civil Affairs and Ministry of Education, Beijing Normal University, Beijing 100875, china 3. College of Computer Science and Technology, Jilin University, Changchun 13.012, china College of Resources and Civil Engineering Northeastern University Shenyang 110004 China Academy of Disaster Reduction and Emergency management Ministry of Civil Affairs and Ministry of Education Beijing Normal University Beijing 100875 China College of Computer Science and Technology Jilin University Changchun 130012 China

Technologies of underground mobile positioning were proposed based on LiDAR data and coded sequence pattern landmarks for mine shafts and tunnels environment to meet the needs of fast and accurate positioning and navigation of equipments in the mine underground without satellite navigation signals. A coded sequence pattern was employed for automatic matching of 3. scans. The methods of SIFT feature, Otsu segmentation and fast hough transformation were described for the identification, positioning and interpretation of the coded sequence patterns, respectively. The POSIT model was presented for speeding up computation of the translation and rotation parameters of LiDAR point data, so as to achieve automatic 3. mapping of mine shafts and tunnels. The moving positioning experiment was applied to evaluating the accuracy of proposed pose estimation method from LiDAR scans and coded sequence pattern landmarks acquired in an indoor environment. The performance was evaluated using ground truth data of the indoor setting so as to measure derivations with six degrees of freedom.

关键词： LiDAR coded sequence pattern mobile positioning SLAM algorithm POSIT algorithm

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Uniform estimate for maximum of randomly weighted sums with applications to insurance risk theory

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Science china Mathematics 2005年第10期48卷 1379-1394页

作者： WANG Dingcheng~1 SU Chun~2 & ZENG Yong~1 1. school of management and school of Applied Mathematics,University of Electronic Science and Technology of {3.,Chengdu 610054,{3. 2. Department of Statistics and Finance,University of Science and Technology of {3.,Hefei 23.026,{3. school of management and school of Applied Mathematics University of Electronic Science and Technology of China Chengdu China Department of Statistics and Finance University of Science and Technology of China Hefei China

This paper obtains the uniform estimate for maximum of sums of independent and heavy-tailed random variables with nonnegative random weights, which can be arbitrarily dependent of each other. Then the applications to ... 详细信息

关键词： dependent stochastic return, discount factor, heavy-tails, discrete time insurance risk model, maxima of randomly weighted sums, ruin probability, tail probabilities, uniformly asymptotic estimate.

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