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LANDFORM MORPHOLOGIC RELATIONS BETWEEN INTER-GULLIED AND GULLIED LAND AREAS——A CASE STUDY OF THE WANGJIAGOU WATERSHED IN THE WEST OF SHANXI PROVINCE

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International Journal of Sediment Research 2006年第1期21卷 62-73页

作者： Hao CHEN1, Hai-yan FANG2, Qiang-guo CAI 3, Guang-lin LIANG4.and Zong-qi YUE51Associate Professor, 2Doctor, 3Professor, 4.ostgraduate for master, Key Laboratory of Water Cycle and Related Land Surface Processes, Institute of Geographical Sciences and Natural Resources Research, Chinese Academy of Sciences, beijing, 100101, China 1Professor, College of Resource and Environment, Southwest Agricultural university, Chongqing, 4.0716, China 2 Doctor, 4.Postgraduate for master, Graduate university of Chinese Academy of Sciences, beijing, 10004., China 5 Associate Professor, Department of Civil Engineering, Hong Kong university, Hong Kong, China Key Laboratory of Water Cycle and Related Land Surface Processes Institute of Geographical Sciences and Natural Resources Research Chinese Academy of Sciences Beijing 100101 China Department of Civil Engineering Hong Kong University Hong Kong China

Previous studies on erosional relations between inter-gullied and gullied lands have mainly concentrated on exploration of water and sediment relations, with few quantitative studies of evolution relations between inter-gullied land and gullied landform erosion in small catchments. This paper, using information from a 1:5000 digital orthophotomap (DOM), digital elevation model (DEM), and topographic map of the same period and of the same scale, quantitatively analyzes the impact and interactions of inter-gullied and gullied land geomorphologic characteristics on the dissected extent of a catchment using orthogonal polynomial regression analysis. Results indicate that gullies play a leading role in the catchment morphologic evolution and extent of cracked ground surface. When inter-gullied land areas are the same, a 0.1 km2 gullied land area has the maximum effect on the erosive evolution intensity of the catchment cracked degree. The smaller the catchment area is, the greater the extent of cracked ground surface and gully intensity would be. The geomorphologic evolution mechanism of gullied catchments can be explained as a function of geomorphologic indicators of inter-gullied and gullied land characteristics.

关键词： Inter-gullied land erosion Gully erosion Small catchments Gullied land area Loess Plateau

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同伴团体对儿童青少年学业成就和社会功能关系的影响

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心理学探新 2003年第2期23卷 45-50页

作者：杨渝川郑淑杰陈欣银常磊何云峰北京师范大学心理学院北京100875 加拿大西安大略大学心理学系香港中文大学心理系香港大学心理学系

运用同伴评价、教师评估和学校记录等多种渠道收集关于同伴团体、社会功能、同伴接纳以及学业成就的资料 ,旨在考察同伴团体与儿童青少年学业成就和社会功能的关系。研究发现 :绝大多数儿童青少年都有自己的同伴团体。这些同伴团体在学... 详细信息

运用同伴评价、教师评估和学校记录等多种渠道收集关于同伴团体、社会功能、同伴接纳以及学业成就的资料 ,旨在考察同伴团体与儿童青少年学业成就和社会功能的关系。研究发现 :绝大多数儿童青少年都有自己的同伴团体。这些同伴团体在学业成就上有很高的同质性。学业成就与社会适应无论在团体内的个体水平还是在团体水平上都密切相关。而且 ,团体的学业表现是个体学业成就和社会适应间的重要调节因素 ,表明团体学业规范对个体水平上学业成就与社会功能的关系有增强或是减弱的作用。这项研究再一次证明同伴团体在儿童个体发展中的重要意义。

关键词：同伴团体青少年学业成就社会功能社会能力反向提名测验同伴接纳

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Non-Darcy flow in oil accumulation (oil displacing water) and relative permeability and oil saturation characteristics of low-permeability sandstones

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Petroleum Science 2010年第1期7卷 20-30页

作者： Zeng Jianhui Cheng Shiwei Kong Xu Guo Kai Wang Hongyu State Key Laboratory of Petroleum Resources and Prospecting China University of Petroleum Beijing 102249 China school of Natural Resources and information Technology China University of Petroleum Beijing 102249 China CNPC Greatwall Drilling Company Beijing 100101 China

Hydrocarbon resources in low-permeability sandstones are very abundant and are extensively distributed. Low-permeability reservoirs show several unique characteristics, including lack of a definite trap boundary or caprock, limited buoyancy effect, complex oil-gas-water distribution, without obvious oil-gas-water interfaces, and relatively low oil （gas） saturation. Based on the simulation experiments of oil accumulation in low-permeability sandstone （oil displacing water）, we study the migration and accumulation characteristics of non-Darcy oil flow, and discuss the values and influencing factors of relative permeability which is a key parameter characterizing oil migration and accumulation in low-permeability sandstone. The results indicate that： 1） Oil migration （oil displacing water） in low- permeability sandstone shows non-Darcy percolation characteristics, and there is a threshold pressure gradient during oil migration and accumulation, which has a good negative correlation with permeability and apparent fluidity; 2） With decrease of permeability and apparent fluidity and increase of fluid viscosity, the percolation curve is closer to the pressure gradient axis and the threshold pressure gradient increases. When the apparent fluidity is more than 1.0, the percolation curve shows modified Darcy flow characteristics, while when the apparent fluidity up＂ non-Darcy percolation curve; 3） Oil-water is less than 1.0, the percolation curve is a ＂concave- two-phase relative permeability is affected by core permeability, fluid viscosity, apparent fluidity, and injection drive force; 4. The oil saturation of low- permeability sandstone reservoirs is mostly within 35%-60%, and the oil saturation also has a good positive correlation with the permeability and apparent fluidity.

关键词： Non-Darcy flow relative permeability oil saturation low-permeability sandstone

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Atmospheric frontal gravity waves observed in satellite SAR images of the Bohai Sea and Huanghai Sea

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Acta Oceanologica Sinica 2010年第5期29卷 35-43页

作者： LIU Shuming LI Ziwei YANG Xiaofeng Pichel William G YU Yang ZHENG Quanan LI Xiaofeng The First Institute of Oceanography State Oceanic Administration Qingdao 266061 China National Marine Data and information Service Tianjin 300171 China Institute of Remote Sensing Applications Chinese Academy of Science Beijing 100101 China NOAA/NESDIS Center for Satellite Applications and Research Camp Springs MD 20746-4304 USA Department of Atmospheric and Oceanic Science University of Maryland Maryland 20742-2425 USA IMSG at NOAA/NESDIS NOAA E/RA3 WWBG Room 102 5200 Auth Road Camp Springs MD 20746-4304 USA.

In the satellite synthetic aperture radar（SAR） images of the Bohai Sea and Huanghai Sea,the authors observe sea surface imprints of wave-like patterns with an average wavelength of 3.8 *** SAR observations with sea surface wind fields and surface weather maps,the authors find that the occurrence of the wave-like phenomena is associated with the passing of atmospheric *** authors define the waves as atmospheric frontal gravity *** dynamical parameters of the wave packets are derived from statistics of 9 satellite SAR images obtained from 2002 to 2008.A two-dimensional linear physical wave model is used to analyze the generation mechanism of the *** atmospheric frontal wave induced wind variation across the frontal wave packet is compared with wind retrievals from the SAR *** CMOD-5（C-band scatterometer ocean geophysical model function） is used for SAR wind retrievals VV（transmitted vertical and received vertical） for ENVISAT and HH（transmitted horizontally and received horizontally） for RADARSAT-1.A reasonable agreement between the analytical solution and the SAR observation is *** new SAR frontal wave observation adds to the school of SAR observations of sea surface imprints of AGWs including island lee waves,coastal lee waves,and upstream Atmospheric Gravity Waves（AGW）.

关键词： Atmospheric gravity waves atmospheric front generation mechanism synthetic aperture radar

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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 730000, China 2. Key Laboratory of Gas Geochemistry, Institute of Geology and Geophysics, Chinese Academy of Sciences, Lanzhou 730000, China 3. College of Resources Science & Technology, beijing Normal university, beijing 100875, China 1. Resources and Environmental school Lanzhou University Lanzhou 730000 China 2. Key Laboratory of Gas Geochemistry Institute of Geology and Geophysics Chinese Academy of Sciences Lanzhou 730000 China 3. College of Resources Science & Technology Beijing Normal University Beijing 100875 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 ~3He/~4.e in almost all samples range from 0.82 Ra to 2.74.Ra, whereas^(4.)Ar/^(36)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/~3He range from 27.6 x 10~9 to 1050 x 10~9,N_2/Ar from 927 to 56612, and N_2/~3He 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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基于GNSS/GIS/RS集成技术的铁路列车运营监控

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计算机工程与应用 2003年第23期39卷 224-228页

作者：张李勇张飞舟北京航空航天大学自动化科学及电气工程学院北京100083 北京大学遥感与地理信息系统研究所北京100871

文章阐述了全球导航卫星系统GNSS(GlobalNavigationSatelliteSystem)、地理信息系统GIS(GeographicInfor-mationSystem)、遥感RS(RemoteSensing)技术的基本特征、相互关系及其集成基本方式。针对我国目前智能铁路运输系统发展趋势,运用GNSS/GIS/RS集成技术,进行铁路列车运营监控探讨性研究。该集成导航技术将卫星导航、地理信息系统以及遥感技术融合在一起,可实现铁路运输管理“自动化”、列车行驶“智能化”,减少运输服务时间,提高铁路运输整体效益,并且具有良好的实用价值。

关键词：全球定位系统全球导航卫星系统地理信息系统遥感铁路智能交通系统运营监控

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Design theory and method of multivariate hash function

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Science China(information Sciences) 2010年第10期53卷 1977-1987页

作者： WANG HouZhen 1,2 , ZHANG HuanGuo 1 , WU QianHong 1 , ZHANG Yu 1 , LI ChunLei 1 & ZHANG XinYu 1 1 The Key Laboratory of Aerospace information Security and Trusted Computing, Ministry of Education, school of Computer, Wuhan university, Wuhan 4.0072, China 2 Key Laboratory of Mathematics Mechanization, beijing 100080, China 1. The Key Laboratory of Aerospace information Security and Trusted Computing Ministry of Education School of Computer Wuhan University Wuhan 430072 China2. Key Laboratory of Mathematics Mechanization Beijing 100080 China

This paper proposes a novel hash algorithm whose security is based on the multivariate nonlinear polynomial equations of NP-hard problem over a finite field and combines with HAIFA iterative framework. Over the current widely used hash algorithms, the new algorithm has the following advantages: its security is based on a recognized difficult mathematical problem; the hash length can be changed freely; its design can be automated such that users may construct specific hash function meeting the actual needs. Furthermore, we discuss the security, efficiency and performance of the new algorithm. Under some related difficult mathematical assumptions and theoretical analysis, the new algorithm is proven practical by the experiment results, and capable of achieving security of an ideal hash function by choosing suitable parameters. In addition, it can also be used as a pseudo-random number generator for the good randomness of its output.

关键词： cryptology hash function MQ problem multivariate polynomials

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PLS1回归对多变量信息的综合与筛选作用分析

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数理统计与管理 1998年第4期17卷 46-49,61页

作者： Wang Huiwen(school of Management,beijing university of Aeronautics and Astronaudics) 北京航空航天大学

王惠文，ＰＬＳ１回归对多变量信息的综合与筛选作用分析，数理统计与管理，１９９８，１７（４），４６～４９。本文讨论了ＰＬＳ１回归对多变量系统中的信息进行综合与筛选的工作策略。通过例证分析指出，ＰＬＳ１回归方法可以有效地... 详细信息

王惠文，ＰＬＳ１回归对多变量信息的综合与筛选作用分析，数理统计与管理，１９９８，１７（４），４６～４９。本文讨论了ＰＬＳ１回归对多变量系统中的信息进行综合与筛选的工作策略。通过例证分析指出，ＰＬＳ１回归方法可以有效地提取对系统解释性最强的综合变量，排除重叠信息或无解释意义的信息干扰。

关键词： PLS1回归方法变量多重相关性信息综合

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SLAM技术及其在测绘领域中的应用

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测绘通报 2018年第3期 18-24页

作者：黄鹤佟国峰夏亮李勇岳晓阳姜斌北京建筑大学测绘与城市空间信息学院北京102616 北京建筑大学北京未来城市设计高精尖创新中心北京100044 东北大学信息科学与工程学院辽宁沈阳110819 欧思徕(北京)智能科技有限公司北京102300

即时定位与地图构建(SLAM)是机器人领域的关键技术之一。基于SLAM技术可以对视觉信息和激光雷达数据进行三维重建与地图构建,这些三维模型及地图在测绘领域有着广泛的应用,尤其是更加精确的三维模型数据,对于精确测量和高精度导航等方... 详细信息

即时定位与地图构建(SLAM)是机器人领域的关键技术之一。基于SLAM技术可以对视觉信息和激光雷达数据进行三维重建与地图构建,这些三维模型及地图在测绘领域有着广泛的应用,尤其是更加精确的三维模型数据,对于精确测量和高精度导航等方面有着重要的意义。因此,本文从测绘领域的视角对SLAM技术的发展、原理及其在测绘领域的应用进行了论述和讨论,且对SLAM技术在测绘领域的应用前景进行了展望,为国内外测绘和机器人方面的研究人员提供了重要参考。

关键词： SLAM技术测绘领域技术应用点云三维建模

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Estimation of forest volumes by integrating Landsat TM imagery and forest inventory data

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Science China(Technological Sciences) 2006年第z1期49卷 54-62页

作者： GU Huiyan, DAI Limin, WU Gang, XU Dong, WANG Shunzhong &WANG Hui Institute of Applied Ecology, Chinese Academy of Sciences, Shenyang 110016, China school of Forestry, Northeast Forestry university, Harbin 15004., China State Key Lab of Systems Ecology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, beijing 100085, China Graduate university of Chinese Academy of Sciences, beijing 100039, China 1. Institute of Applied Ecology Chinese Academy of Sciences Shenyang 110016 China 2. school of Forestry Northeast Forestry University Harbin 150040 China 3. State Key Lab of Systems Ecology Research Center for Eco-Environmental Sciences Chinese Academy of Sciences Beijing 100085 China 4. Graduate university of Chinese Academy of Sciences Beijing 100039 China

Accurate information about forest volumes is essential for forest management planning. The survey interval of the Forest Resource Inventory of China (FRIC) is too long to meet the demand for timely decision-making required for forest protection, management, and utilization. Analysis of satellite imagery provides good potential for more frequent reporting of forest parameters. In this study, we describe an application of the k-nearest neighbors (kNN) method to Landsat TM imagery for improving estimation of forest volumes. Several spectral features were tested and compared in forest volume estimations, including normalized difference vegetation index, environmental vegetation index, and the combination of the spectral features. The combined index resulted in the most accurate volume estimations. The kNN estimator and the combined index were then used in forest volume estimation. The estimation error (RMSE) of the total volume was4..2%, much lower than those for Larix forest (the RMSE was 51.7%) and those for the Korean pine and broadleaved forests (the estimation errors were over 71.7% and 88.19%,respectively). This preliminary study demonstrates the potential of forest volume estimations with remote sensing data to provide useful information for forest management if only limited ground information is available.

关键词： forest inventory, landsat TM, k-nearest neighbors, spectral extraction.

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