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Combination of drainage, water supply and environmental protection as well as rational distribution of water resource in Zhengzhou mining district

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Science China Earth Sciences 2005年第10期48卷 1768-1779页

作者： WU Qiang1, LI Duo1,2, DI Zhiqiang3, MIAO Ying3, ZHAO Suqi4.& GUO Qiwen5 1. Resource Exploitation Engineering College, CUMT, beijing 100083, China 2. Shijiazhuang Engineering College, University of Economics, Shijiazhuang 050031, China 3. Shenyang Institute of Geology and mineral Resources, Shenyang 110032, China 4. state adminstration of coal mine safety, beijing {4. China 5. Zhengzhou coal mine Company (Group), Zhengzhou 4.2371, China Resource Exploitation Engineering College CUMT Beijing China Shijiazhuang Engineering College University of Economics Shijiazhuang China Shenyang Institute of Geology and mineral Resources Shenyang China state adminstration of coal mine {4. beijing China Zhengzhou coal mine Company (Group) Zhengzhou China

The geological condition of coalfield is much complex in China. With increasing in mining depth and drainage amount, the contradiction of drainage, water supply and environ-mental protection is becoming more and more serious. However, the contradiction can be solved by the scientific management of optimizing combination of drainage, water supply and environ-mental protection. The Philip multiple objectives simplex method used in this article has searched for a possible solution at the first step, and then it goes on searching to find out whether there is a weight number that can lead the solution to the biggest. It can reduce the randomness and diffi-culty of traditional weight method which determine the weight number artificially. Some beneficial coefficients are vague and the number is larger in the model of water resource dispatch. So the vague layer analysis method can consider these vague factors fully, combining the qualitative and quantitative analysis together. Especially, this method can quantify the experiential judge-ment of policy decider, and it will turn to be more suitable if the structure of objective factors is complex or the necessary data are absent. In the paper, the two methods above are used to solve the plans of drainage, water supply and optimizing distribution of water resource in the Zhengzhou mining district.

关键词： combination of drainage, water supply and environmental protection, Philip multiple objective simplex method, vague layer analysis method, distribution of water resource.

The steady-state solution of dendritic growth from the undercooled binary alloy melt with the far field flow

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Science China(Technological Sciences) 2009年第8期52卷 2280-2287页

作者： CHEN MingWen1,2, WANG ZiDong2 & XU JianJun2,3,4.1 School of Applied Sciences, University of Science and Technology beijing, beijing 100083, China 2 School of Materials Science and Engineering, University of Science and Technology beijing, beijing 100083, China 3 School of Mathematical Sciences, Nankai University, Tianjin 300071, China 4.Department of Mathematics and Statistics, McGill University, Montreal H3A 2K6, Canada School of Applied Sciences University of Science and Technology Beijing Beijing 100083 China School of Materials Science and Engineering University of Science and Technology Beijing Beijing 100083 China School of Mathematical Sciences Nankai University Tianjin 300071 China Department of Mathematics and Statistics McGill University Montreal H3A 2K6 Canada

The steady-state dendritic growth from the undercooled binary alloy melt with the far field flow is considered. By neglecting the interface energy, interface kinetics and buoyancy effects in the system, we obtaine the steady-state solution for the case of the large Schmidt number, in terms of the multiple variable expansion method. The changes of the temperature and concentration fields, the morphology of the interface, the normalization parameter and the Peclet number of the system induced by uniform external flow are derived. The results show that, compared with the system of dendritic growth from undercooled pure melt, the convective flow in the system of growth from undercooled binary alloy has stronger effects on the morphology of the interface. Nevertheless, the shape of the interface still remains nearly a paraboloid.

关键词： binary alloy melt convection dendritic growth interfaces steady-state solution multiple variable expansion method

Estimating surface evapotranspiration using combined MODIS and CBERS-02 data

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Science China(Technological Sciences) 2005年第S2期48卷 145-160页

作者： XIN Xiaozhou1,2, LIU Qinhuo1, TANG Yong1,3, TIAN Guoliang1, GU Xingfa1, LI Xiaowen1,2, ZHENG Hongsheng4.& CHEN Jiayi4.1. state Key Laboratory of Remote Sensing Science, Institute of Remote Sensing Applications, Chinese Academy of Sciences, beijing 100101, China 2. Research Center for Remote Sensing and GIS, Department of Geography, beijing Normal University, beijing 100875, China 3. Graduate University of Chinese Academy of Sciences, beijing 100039, China 4. Department of Atmospheric Physics, Peking University, beijing 100871, China 1. state Key Laboratory of Remote Sensing Science Institute of Remote Sensing Applications Chinese Academy of Sciences 100101 Beijing China2. Research Center for Remote Sensing and GIS Department of Geography Beijing Normal University 100875 Beijing China3. Graduate University of Chinese Academy of Sciences 100039 Beijing China4. Department of Atmospheric Physics Peking University 100871 Beijing China

Spatial scale error is one of the most serious problems in the estimates of land surface heat fluxes of sensible and latent from satellite-borne data such as MODIS 1km resolution reflectance and emissive data. One of the feasible and economic ways to decrease the spatial scale error is to use high resolution land use class data together with the MODIS data. CBERS-02 data were used to produce land use class of Baiyangdian area, Hebei Province, China in the autumn of 2004. The area ratio of each class in MODIS pixel was calculated, and used to derive the heat fluxes of the mixed pixel. The results showed that the estimated heat fluxes of soil, sensible and latent have been changed remarkably after using the high resolution land class data. It could be concluded from the comparison between simulated and ground-measured fluxes as well as the theoretical analysis that high resolution land class data are useful to diminishing the scale error of heat fluxes estimated from low resolution satellite data.

关键词： surface evapotranspiration spatial scale error MODIS CBERS land class.

The quantification of remote sensing

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Science China(Technological Sciences) 2005年第S2期48卷 1-11页

作者： GU Xingfa1,2,3,TIAN Guoliang1,2, LI Xiaowen1,2 & GUO Jianning4.1. state Key Laboratory of Remote Sensing Science, Jointly Sponsored by the Institute of Remote Sensing Applications of Chinese Academy of Sciences and beijing Normal University, beijing 100101, China 2. The Center for National Spaceborne Demonstration, beijing 100101, China 3. Institut National de la Recherche Agronomique, Climat Sol Environnement, 84.14.Avignon, France 4. China Center for Resource Satellite Data and Application, beijing 100830, China Chinese Acad Sci Inst Remote Sensing Applicat State Key Lab Remote Sensing Sci Beijing 100101 Peoples R China beijing Normal Univ State Key Lab Remote Sensing Sci Beijing 100101 Peoples R China Ctr Natl Spaceborne Demonstrat Beijing 100101 Peoples R China Inst Natl Rech Agron F-84914 Avignon France China Ctr Resource Satellite Data & Applicat Beijing 100830 Peoples R China

The paper firstly defined the remote sensing information quantification, analyzed the necessity of developing remote sensing quantification, figured out the application guidelines requirement, and pointed out the importance of quantification research. Then taking the remote sensing application research of CBERS-02 data quantification as the example, the paper described the whole quantification system of “remotely sensed digital signal-radiation information-field parameter inversion”. Finally the paper gave the prospect for the development trend of the quantitative remote sensing.

关键词： remote sensing information quantification CBERS-02 radiometric calibration surface parame- ter reversion.

Modeling of state of vegetation and soil erosion over large areas

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International Journal of Sediment Research 2008年第3期23卷 181-196页

作者： Zhao-Yin WANG1*, Guangqian WANG2, and Guohe HUANG31 Prof., state Key Laboratory of Hydroscience and Engineering, Tsinghua University, beijing 100084. China2 Prof., state Key Laboratory of Hydroscience and Engineering, Tsinghua University, beijing 100084. China3 Prof. and Canada Research Chair, Environmental Systems Engineering Program, Faculty of Engineering, University of Regina, Regina, Sask S4. 0A2, Canada [a]Prof. state Key Laboratory of Hydroscience and Engineering Tsinghua University beijing 100084 China [b]Prof. state Key Laboratory of Hydroscience and Engineering Tsinghua University beijing 100084 China Tel: 86-10-6278174. Fax: 86-10-627724.3 [c]Prof. and Canada Research Chair Environmental Systems Engineering Program Faculty of Engineering University of Regina Regina Sask S4. 0A2 Canada

A vegetation-erosion model was developed to assess the extent of soil erosion and development trend of vegetation in the context of existing and contemplated vegetation-based soil erosion controls under different climatic, topographical and soil conditions. The model recognizes four vegetation-mediated soil erosion states: (i) an expanding vegetation coverage coupled with reduced erosion (C), (ii) a deteriorating vegetation coverage coupled with increased erosion (A), (iii) two transitional states between A and C, one with increasing erosion and vegetation coverage (B) and the other with decreasing erosion and vegetation coverage (D). With the model, the vegetation-erosion state of any particular area can be quantitatively described, by way of a vegetation-erosion chart, for varying climate, soil and topographic conditions, as demonstrated for the Xishan region, the East River basin, the Wangjiagou and Anjiagou watersheds (Loess Plateau), and the Xiaojiang watersheds (hot and dry valleys in the upper Yangtze River basin) in China. This paper presents the principles and results of area-specific investigations that track the fractions of the areas covered by vegetation and experiencing soil erosion (with soil loss determined in t/km2yr). This is done within the context of local soil erosion control initiatives via re-vegetation efforts, or the lack thereof, over the course of 30 years. The effectiveness of reforestation and erosion-control measures vary under different climatic, topographical and soil conditions. The vegetation may be quickly restored in the hot and wet East River basin but is very difficult on the dry and cold Loess Plateau. In the hot and dry valleys the vegetation can be restored if erosion is controlled and intensive reforestations for small watersheds are performed.

关键词： Soil erosion Vegetation coverage Loess Plateau Vegetation-erosion chart Reforestation

Construction of nonbinary quantum cyclic codes by using graph method

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Science in China(Series F) 2005年第6期48卷 693-702页

作者： LIU Tailin1,2,3, WEN Qiaoyan1 & LIU Zihui4.1. School of Science, beijing University of Posts and Telecommunications, beijing 100876, China 2. state Key Laboratory of Integrated Services Network, Xidian University, Xi’an 710071,China 3. Shandong Finance Institute, Jinan 250014. China 4. School of Mathematical Sciences, Peking University, beijing 100871, China 1. School of Science Beijing University of Posts and Telecommunications 100876 Beijing China 2. state Key Laboratory of Integrated Services Network Xidian University 710071 Xi’an China 3. Shandong Finance Institute 250014 Jinan China 4. School of Mathematical Sciences Peking University 100871 Beijing China

Using the graph method proposed by Schlingemann and Werner, this paper introduces a technique to construct nonbinary quantum cyclic codes and provides a specific example. We also construct the quantum codes [[8, 2, 4.... 详细信息

关键词： nonbinary quantum stabilizer codes quantum cyclic codes

Decoding algorithms for shortened-extended turbo product codes in WiMAX systems

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Science in China(Series F) 2009年第12期52卷 2415-2423页

作者： XU ChangLong1,3,4. YANG Wei1,2 & YE WeiChen4.1 state Key Laboratory of Networking and Switching Technology, beijing University of Posts and Telecommunications, beijing 10004., China 2 state Key Laboratory of Rail Traffic Control and {4., beijing Jiaotong University, beijing 10004., China 3 National Mobile Communications Research Laboratory, Southeast University, Nanjing 210096, China 4.Intel Corporation, beijing Kerry Center, Guanghua Road 1, beijing 100020, China state Key Laboratory of Networking and Switching Technology Beijing University of Posts and Telecommunications Beijing 100044 China state Key Laboratory of Rail Traffic Control and safety Beijing Jiaotong University Beijing 100044 China National Mobile Communications Research Laboratory Southeast University Nanjing 210096 China Intel Corporation Beijing Kerry Center Guanghua Road 1 Beijing 100020 China

The component codes of turbo product codes in WiMAX systems are extended Hamming codes and single parity check codes as well as their shortened forms, In this paper, three novel iterative decoding algorithms based on Chase, MAP algorithms and their combination are proposed for shortened-extended turbo product codes. The iterative decoding algorithm based on Chase algorithm is proposed to reduce the decoding complexity without any performance loss. An efficient MAP algorithm is then proposed to decode the component codes of shortened single parity check codes and shortened-extended Hamming codes. A comprehensive performance comparison of the proposed decoding schemes is conducted for three typical classes of turbo product codes in WiMAX OFDMA systems. The suitable decoding algorithms are recommended for different classes based on the simulation results.

关键词： block code product code iterative decoding

Sorption behavior of U(VI), ^(234.U(VI) and ^(238)U(VI) onto fracture-filling clays in Beishan granite, Gansu: Application to selecting the site of high-level radwaste repository in China

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Science China Earth Sciences 2005年第10期48卷 1649-1655页

作者： MIN Maozhong1,2, LUO Xingzhang3, WANG Ju4. JIN Yuanxin4.& WANG Rucheng1 1. Department of Earth Sciences, state Key Laboratory of mineral Deposit Research, Nanjing University, Nanjing 210093, China 2. Center of Materials Analysis, Nanjing University, Nanjing 210093, China 3. Department of Environmental Science and Engineering, Nanjing University, Nanjing 210093, China 4. beijing Geology Institute, Nuclear Industry, beijing 100029, China Department of Earth Sciences State Key Laboratory of Mineral Deposit Research Nanjing University Nanjing China Center of Materials Analysis Nanjing University Nanjing China Department of Environmental Science and Engineering Nanjing University Nanjing China beijing Geology Institute Nuclear Industry beijing China

The first results of sorption experiments of U(VI), 234.(VI) and 238U(VI) onto original (unpurified) fracture-filling clays from No.1 monzonitic granite intrusion, Beishan area, Gansu Province, China are reported. The monzonitic granite intrusion is a potential location for a high-level radwaste (HLW) repository in China. The present experimental results show that the maximum U(VI) sorption reached 92% at near-neutral pH and the distribution coefficient (Kd) was 1226 mL/g. A high sorption capacity of the fracture-filling clays in host rock on radioactive ele-ments is necessary for HLW deep geological disposal repository. No preferential sorption of 234. onto the clays was found. Finally, the sorption of U(VI) onto the clays was also modeled using a surface complexation model.

关键词： HLW geological disposal repository, granite, uranium, radionuclide, clay, sorption.

The onset and advance of the Asian summer monsoon

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Science Bulletin 2006年第1期51卷 80-88页

作者： Lü Junmei1,2,4. ZHANG Qingyun1, TAO Shiyan1 & JU Jianhua3 1. state Key Laboratory of Numerical Modeling for Atmospheric Sci- ences and Geophysical Fluid Dynamics, Institute of Atmospheric Physics, Chinese Academy of Sciences, beijing 100029, China 2. Department of Atmospheric Sciences, Yunnan University, Kunming 650091, China 3. China Meteorological Administration Training Centre, beijing 100081, China 4. Graduate School of Chinese Academy of Sciences, beijing 100039, China state Key Laboratory of Numerical Modeling for Atmospheric Sciences and Geophysical Fluid Dynamics Institute of Atmospheric Physics Chinese Academy of Sciences Beijing 100029 China Department of Atmospheric Sciences Yunnan University Kunming 650091 China Graduate School of Chinese Academy of Sciences Beijing 100039 China China Meteorological Administration Training Centre Beijing 100081 China

Based on the daily outgoing longwave radiation (OLR) data from National Oceanic and At- mospheric Administration (NOAA) satellites, the Cli- mate Prediction Center’s merged analysis of pre- cipitation (CMAP) data and the National Centers for Environmental Prediction/National Center for At- mospheric Research (NCEP/NCAR) reanalysis dataset, the mean intraseasonal variability of the Asian summer monsoon (ASM) is investigated by using power spectrum analysis, band-pass filter, and diagnostic analyses. The processes of the onset and advance of monsoon over the southern part of Indo- china Peninsula, the east coast of Bay of Bengal, the South China Sea and the Indian subcontinent are explored. It is found that there is an abrupt change in OLR, precipitation and zonal wind during the onset and advance of the ASM. It is also indicated that the southern part of Indochina Peninsula and the adja- cent Andaman Sea is the region where the earliest onset of the ASM occurs in the 2nd pentad of May.

关键词： Asian summer monsoon intraseasonal variability onset advance.