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Exergy and ecological modelling of lake environment

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Journal of environmental sciences 1998年第4期10卷 114-121页

作者： Zhang Yong ze environmental Engineering Center, Chinese Research Academy of environmental {2.s, {3. 100012. China Wang Xuan institute of environmental {2., beijing normal university, beijing 100875, China

The thermodynamic theories and ecological theories can be integrated effectively by exergy(biogeochemical energy of the system) to study the environmental problems of the lakes and reservoirs. In this paper, the applications of exergy in the ecological modelling of lake environment were reviewed. Results showed that exergy can be used as a goal function to estimate the parameters of the ecological model for lakes and reservoirs and to develop the structural dynamic models accounting for the changes in lake ecosystems, and as an ecological indicators for the development and evolution of lake ecosystems.

关键词： exergy ecological indicator structural dynamic model goal function.

Preliminary results of the study on wind erosion in the Qinghai-Tibetan Plateau using 13.Cs technique

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Chinese science Bulletin 2000年第11期45卷 1019-1025页

作者： YAN Ping, DONG Guangrong, ZHANG Xinbao & ZHANG Yiyun1. Key Laboratory of environmental Change and Natural Disaster, the Ministry of Education of China, beijing normal university,{2., China 2. {3. of Desert Research, Chinese Academy of sciences, Lanzhou 73.000, China 3. {3. of Mountain Hazards and Environment, Chinese Academy of sciences, Chengdu 610041, China 4. Department of Physics, Sichuan Union university, Chengdu 610041, China Key Laboratory of environmental Change and Natural Disaster the Ministry of Education of China Beijing Normal University Beijing China institute of Desert Research Chinese Academy of Sciences Lanzhou China institute of Mountain Hazards and Environment Chinese Academy of Sciences Chengdu China Department of Physics Sichuan Union University Chengdu China

The worldwide fallout of caesium-13. (13.Cs) associated with the nuclear weapon tests during the 1950s and 1960s has provided a valuable man-made tracer for studies of soil erosion and sediment delivery. But relatively few researchers have used it to estimate wind erosion. In this note, the 13.Cs technique is introduced into the studies of wind erosion and its modern processes inthe Qinghai-Tibetan Plateau. Two 13.Cs reference inventories of 982.11 and 2.3.6.04 Bq · m-2.wereestablished preminarily, distributed in the south and middle-north parts of the studied arearespectively. By analyzing the patterns of 13.Cs depth profiles from sampling sites, the aeolianprocesses of erosion and deposition in nearly 40 years have been revealed, i.e. the shrub coppicedunes (S1) and semi-fixed dunefields (S3. experienced the alternation of erosion and deposition,while the grasslands (S4, S6 and S7) and dry farmlands (S5) suffered erosion only. By using 13.Csmodel, the average wind erosion rates for shrub coppice

关键词： 13.Cs technique Qinghai-Tibetan Plateau wind erosion.

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science China(Life sciences) 2009年第8期52卷 780-788页

作者： YANG Bo1,YANG SuYong2.ZHAO Lun3.YIN LiuHua1,LIU Xu1& AN ShaSha1 1 Laboratory of Psychology,School of Sociology,China university of Political science and Law,{2. 102.49,China 2.National Key Laboratory of Cognitive Neurosciences and Learning,{2. normal university,{2. 100875,China 3.institute of Language,Xuzhou normal university,Xuzhou 2.1116,China Laboratory of Psychology School of Sociology China University of Political Science and Law Beijing 102249 China National Key Laboratory of Cognitive Neurosciences and Learning Beijing Normal University Beijing 100875 China institute of Language Xuzhou Normal University Xuzhou 221116 China

Inhibitory control dysfunction is regarded as a core feature in *** major objective of this study was to explore the time course of response inhibition in chronic heroin addicts and provide the neurophysiological evidence of their inhibitory control *** amplitudes and latencies of ERP components were studied in fourteen heroin addicts(mean duration of heroin use being(13.54±5.71) years(Mean±SD),average abstinence being((4.67±6.44) months)) and fourteen matched healthy controls with a visual Go/Nogo *** results showed that heroin addicts demonstrated significantly larger Go-N2.amplitudes which results in a decreased N2.Go/Nogo effect,but no statistically significant differences were found between heroin addicts and controls in *** ERP data suggest that fronto-central areas of heroin addicts were impaired during the inhibition process(2.0-3.0 ms) and over-activated to *** impaired early process might reflect an ab{3. conflict monitoring process in heroin *** results consolidate the inhibitory control dysfunction hypothesis in chronic heroin users.

关键词： heroin addicts events-related potentials inhibitory control conflict monitoring response inhibition

Absolute radiometric calibration of CBERS-02.IRMSS thermal band

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science China(Technological sciences) 2005年第S2期48卷 72-90页

作者： ZHANG Yong1,2.3. GU Xingfa1,3.4, YU Tao1,3. ZHANG Yuxiang5, CHEN Liangfu1,3. LI Xiaoying1,2.3. LI Xiaowen1,3.& HE Liming6 1. State Key Laboratory of Remote Sensing science, Jointly Sponsored by the {3. of Remote Sensing Applications of Chinese Academy of sciences and{3., beijing 100101, China 2. Graduate university of Chinese Academy of sciences, beijing 10003., China 3. The Center for National Spaceborne Demonstration, beijing 100101, China 4. Institut National de la Recherche Agronomique, Climat Sol Environnement, 84914 Avignon, France 5. National Satellite Meteorological Center, beijing 100081, China 6. State {13. Protection Administration, beijing 10002., 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 Chinese Acad Sci Grad Univ Beijing 100039 Peoples R China Ctr Natl Spaceborne Demonstrat Beijing 100101 Peoples R China INRA F-84914 Avignon France Natl Satellite Meteorol Ctr Beijing 100081 Peoples R China State Environm Protect Adm Beijing 100029 Peoples R China

Based on the laboratory calibration before launch of CBERS-02.IRMSS thermal infrared channel, the onboard blackbody calibration, the radiometric cross- calibration against TERRA MODIS corresponding channel and the in-flight field calibration at Lake Qinghai: water surface radiometric calibration test site of China on Aug. 17, 2.04 are carried out in this research. When making onboard blackbody calibration of CBERS-02.IRMSS, it is necessary to understand inside structures and light path in IRMSS camera and receive and process calibration blackbody signals at {3. and high temperatures. Onboard blackbody calibration results of each detector are very important to relative radiometric calibration of images processing and absolute radiometric calibration of each detector. In-flight field calibration mainly contains field experiments, obtaining synchronous images, spectrum marching and MODTRAN radiative transmi- ssion computation. Radiometric cross-calibration of CBERS-02.IRMSS thermal band against TERRA MODIS selected 6 times synchronous images of two sensors passing through Lake Qinghai and Lake Taihu from August to December, 2.04 to compute the cross calibration data. Combining the in-flight field calibration and radiometric cross calibration data, the absolute radiometric calibration coefficients are calculated by the linear regression method. This new calibration model can obviously control the radiometric calibration uncertainties aroused by the single point method used in the in-flight calibration of CBERS-02.IRMSS, this kind of sensors cannot receive the cosmic background radiation. In this research, the radiometric calibration coefficients obtained through the linear regression model are 8.53.(gain, unit: DN/W m?2.r?1μm?1) and 44.92.(offset, unit: DN).

关键词： CBERS-02 IRMSS thermal band in-flight field calibration onboard blackbody calibration cross calibration.

Synchronous estimation of DTM and fractional vegetation cover in forested area from airborne LIDAR height and intensity data

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science China(Technological sciences) 2008年第S2期51卷 176-187页

作者： BAO YunFei1,2.CAO ChunXiang1,ZHANG Hao1,CHEN ErXue3.HE QiSheng1,2.HUANG HuaBing1,LI ZengYuan3.LI XiaoWen1,4 & GONG Peng1 1 State Key Laboratory of Remote Sensing science,jointly sponsored by the {3. for Remote Sensing Applications of Chinese Academy of sciences and{3.,beijing 100101,China 2.Graduate university of the Chinese Academy of sciences,beijing 100049,China 3.{3. of Forest Resource Information Technique,the Chinese Academy of Forestry,beijing 100091,China 4 Research Center for Remote Sensing and GIS,Department of Geography and beijing Key Laboratory for Remote Sensing of Environment and Digital Sites,beijing {12. university,beijing 100875,China State Key Laboratory of Remote Sensing science jointly sponsored by the Institute for Remote Sensing Applications of Chinese Academy of Sciences and Beijing Normal University Beijing 100101 China Graduate university of the Chinese Academy of sciences Beijing 100049 China institute of Forest Resource Information Technique the Chinese Academy of Forestry Beijing 100091 China Research Center for Remote Sensing and GIS Department of Geography and Beijing Key Laboratory for Remote Sensing of Environment and Digital Sites Beijing Normal University Beijing 100875 China

We proposed a method to separate ground points and vegetation points from discrete return,small footprint airborne laser scanner data,called skewness change *** method,which makes use of intensity of laser scanner data,is especially applicable in steep,and forested *** does not take slope of forested area into account,while other algorithms consider the change of slope in steep forested *** ground points and vegetation points can be used to estimate digital terrain model(DTM) and fractional vegetation cover,respectively.A few vegetation points which were classified into the ground points were removed as noise before the generation of *** method was tested in a test area of 10000 square meters.A LiteMapper -5600 laser system was used and a flight was carried out over a ground of 700―800 *** this tested area,a total number of 1546 field measurement ground points were measured with a total station TOPCON GTS-602.and TOPCON GTS -7002.for validation of DTM and the mean error value is -18.5 cm and the RMSE(root mean square error) is ±2..9 cm.A data trap sizes of 4m in diameter from airborne laser scanner data was selected to compute vegetation fraction *** of fractional vegetation cover was carried out using 15 hemispherical photographs,which are georeferenced to centimeter accuracy by differential *** gap fraction was computed over a range of zenith angles 10° using the gap light analyzer(GLA) from each hemispherical *** R2.for the regression of fractional vegetation cover from these ALS data and the respective field measurements is *** this study presents a method for synchronous estimation of DTM and fractional vegetation cover in forested area from airborne LIDAR height and intensity data.

关键词： LIDAR intensity skewness synchronous DTM fractional vegetation cover

Discovery and character of the Kunlun-Yellow River Movement

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Chinese science Bulletin 1998年第10期43卷 833-836页

作者： CUI Zhijiu 1, WU Yongqiu 2.3.and LIU Gengnian 1 1. Department of Geography, Peking university, beijing 100871, China 2. Open Research Laboratory of {2. Changes and Natural Disaster of State Education Commission,{3., China Department of Geography Peking University Beijing China Open Research Laboratory of environmental Changes and Natural Disaster of State Education Commission Beijing China Department of Geography Sichuan Normal Uni-versity Chengdu China

Based on geomorphological, tectonic and sedimentary data, a Kunlun Yellow River Tectonic Movement has been recognized in 1 10-0 60 Ma B.P. This tectonic movement, which leads to uplift of the Qinghai_Xizang (Tibet) Plateau from 1 500 to 3.000-3.500 m, is periodic, abrupt and changeable in the movement rate of uplifting and slide slipping.

关键词： Kunlun Mountain Pass 700 kaB.P. tectonic movement.

APPLICATION OF SWAT MODEL IN THE UPSTREAM WATERSHED OF THE LUOHE RIVER

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Chinese Geographical science 2003年第4期13卷 334-339页

作者： ZHANG Xue-song, HAO Fang-hua, CHENG Hong-guang, LI Dao-feng (State Key Laboratory of Water Environment Simulation,institute of environmental {2.s,{3.,beijing 100875,P. R. China) State Key Laboratory of Water Environment Simulation Institute of Environmental Sciences Beijing Normal University Beijing 100875 P. R. China

In the Huanghe (Yellow) River basin,soil erosion is a serious problem,while runoff and sediment yield simulation has not been extensively studied on the basis of GIS (Geographic Information System) and distributed hydrological model. GIS-based SWAT (Soil and Water Assessment Tool) model was used to simulate runoff and sediment in the Huanghe River basin. The objective of this paper is to examine the applicability of SWAT model in a large river basin with high sediment runoff modulus,which could reach 770t/(km2.a). A two-stage "Brute Force" optimization procedure was used to calibrate the parameters with the observed monthly flow and sediment data from 1992.to 1997,and with input parameters set during the calibration process without any change the model was validated with 1998-1999’s observed data. Coefficient of examination (R2. and Nash-Suttcliffe simulation efficiency (Ens) were used to evaluate model prediction. The evaluation coefficients for simulated flow and sediment,and observed flow and sediment were all above 0.7,which shows that SWAT model could be a useful tool for water resources and soil conservation planning in the Huanghe River basin.

关键词： luohe river watershed SWAT model sediment flow

Quantitative relationships between vegetation and several pollen taxa in surface soil from North China

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Chinese science Bulletin 2000年第16期45卷 1519-1523页

作者： LI Yiyin, ZHANG Xinshi & ZHOU Guangsheng1. Department of Urbon and environmental sciences, Peking {2., {3. 100871, China 2. Laboratory of Quantitative Vegetation Ecology, institute of Botany, Chinese Academy of sciences, {3. 100093. China 3. School of Urban and environmental sciences, Northeast normal {2., Changchun 13.02., China Correspondence should be addressed to Li Yiyin Department of Urbon and environmental sciences Peking University Beijing China School of Urban and environmental sciences Northeast Normal University Changchun China Laboratory of Quantitative Vegetation Ecology Institute of Botany Chinese Academy of Sciences Beijing China

According to the vegetation investigation and pollen analysis of surface samples sampled along a precipitation gradient of the Northeast China Transect (NECT), several pollen taxa, including Pinus, Betula, Quercus, Tilia, Acer, Ulmus, Artemisia, Chenopodiaceae, Gramineae and Cyperaceae, were chosen to make the regression and correlation analyses. The results indicated that there exists a close relationship between vegetation and pollen taxa in surface samples. The regression parameters for ten taxa in the forests in the eastern part of NECT were different from those in the steppes in the western part. Pinus, Betula, Artemisia and Chenopodiaceae, which have large slope and y-intercept terms, were over-representative taxa. Acer, Gramineae and Cyperaceae, which have small slope and y-intercept terms, were under-representative taxa. Quercus, Tilia and Ulmus whose slope terms have negative correlation with y-intercept terms were equi-representative taxa. The pollen taxa with large slope or large y-intercept

关键词： pollen taxa in surface soil vegetation regression parameters (slope term and y-intercept term) representation Northeast China Transect (NECT).

An improved exponential filter for fast nonlinear registration of brain magnetic resonance images

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Progress in Natural science:Materials International 2009年第6期19卷 759-767页

作者： Zhiying Long a, Li Yao a,b, Kewei Chen c, Danling Peng a a State Key Laboratory of Cognitive Neuroscience and Learning, beijing normal university,{2., China b School of Information science and Technology, beijing normal university,{2., China c Banner Alzheimer institute (BAI) & Samaritan PET Center, Phoenix, AZ, USA [a]State Key Laboratory of Cognitive Neuroscience and Learning Beijing Normal University Beijing 100875 China [b]School of Information Science and Technology Beijing Normal University Beijing 100875 China [c]Banner Alzheimer Institute (BAI) & Samaritan PET Center Phoenix AZ USA

A linear elastic convolution filter was derived from the eigenfunctions of the Navier-Stokes differential operator by Bro-Nielsen in order to match images with large deformations. Due to the complexity of constructing the elastic convolution filter, the algorithm’s efficiency reduces rapidly with the increase in the image’s size. In our previous work, a simple two-sided exponential filter with high efficiency was proposed to approximate an elastic filter. However, its poor smoothness may degenerate the performance. In this paper, a new exponential filter was constructed by utilizing a modified nonlinear curve fitting method to approximate the elastic filter. The new filter’s good smoothness makes its performance comparable to an elastic filter. Its simple and separable form makes the algorithm’s speed faster than the elastic filter. Furthermore, our experiments demonstrated that the new filter was suitable for both the elastic and fluid models.

关键词： Exponential filter Nonlinear Registration Magnetic resonance imaging