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Application of ensemble kalman filter to geophysical parameters retrieval in remote sensing:A case study of kernel-driven BRDF model inversion

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Science China Earth Sciences 2006年第6期49卷 632-640页

作者： QIN Jun1, YAN Guangjian1, LIU Shaomin1, LIANG Shunlin2, ZHANG Hao1, WANG Jindi1 & LI Xiaowen1 1. State key laboratory of Remote Sensing Science, School of geography and Remote Sensing, Research Center for RS&GIS, beijing normal university, beijing 100875, China 2. Department of geography, 2181 Lefrak Hall, university of Maryland, College Park, MD20742, USA 1. State key laboratory of Remote Sensing Science School of Geography and Remote Sensing Research Center for RS&GIS Beijing Normal University Beijing 100875 China 2. Department of geography 2181 Lefrak Hall University of Maryland College Park MD20742 USA

The use of a priori knowledge in remote sensing inversion has great implications for ensuring the stability of inversion process and reducing uncertainties in retrieved results, especially under the condition of insufficient observations. Common optimization algorithms have difficulties in providing posterior distribution and thus cannot directly acquire uncertainties in inversion results, which is of no benefit to remote sensing application. In this article, ensemble Kalman filter (EnKF) has been introduced to retrieve surface geophysical parameters from remote sensing observations, which has the capability of not merely obtaining inversion results but also giving its posterior distribution. To show the advantage of EnKF, it is compared to standard MODIS AMBRALS algorithm and highly effi-cient global optimization method SCE-UA. The inversion abilities of kernel-driven BRDF models with different kernel combinations at several main cover types are emphatically discussed when observa-tions are deficient and a priori knowledge is introduced into inversion.

关键词： remote sensing inversion, a priori knowledge, posterior distribution, ensemble kalman filter, BRDF, kernel-driven model, albedo.

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Biodegradation of polycyclic aromatic hydrocarbons in sediments from the Daliao River watershed, China

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Journal of Environmental Sciences 2009年第7期21卷 865-871页

作者： QUAN Xiangchun, TANG Qian, HE Mengchang, YANG Zhifeng, LIN Chunye, GUO Wei State key Joint laboratory of Environmental Simulation and Pollution Control, School of Environment, beijing normal university, beijing 100875, China. [a]State key Joint laboratory of Environmental Simulation and Pollution Control School of Environment Beijing Normal University Beijing 100875 China

The Daliao River, as an important water system in Northeast China, was reported to be heavily polluted by polycyclic aromatic hydrocarbons （PAHs）. Aerobic biodegradations of four selected PAHs （naphthalene, phenanthrene, fluorene and anthracene） alone or in their mixture in river sediments from the Daliao River water systems were studied in microcosm systems. Effects of additional carbon source, inorganic nitrogen and phosphorus, temperature variation on PAHs degradation were also investigated. Results showed that the degradation of phenanthrene in water alone system was faster than that in water-sediment combined system. Degradation of phenanthrene in sediment was enhanced by adding yeast extract and ammonium, but retarded by adding sodium acetate and not significantly influenced by adding phosphate. Although PAHs could also be biodegraded in sediment under low temperature （5~C）, much lower degradation rate was observed. Sediments from the three main streams of the Daliao River water system （the Hun River, the Taizi River and the Daliao River） demonstrated different degradation capacities and patterns to four PAHs. Average removal rates （15 or 19 d） of naphthalene, phenanthrene, fluorene and anthracene by sediment were in the range of 0.062-0.087, 0.005-0.066, 0.008- 0.016 and 0-0.059 mg/（L.d）, respectively. As a result, naphthalene was most easily degraded compound, anthracene was the hardest one. In multiple PAHs systems, the interactions between PAHs influenced each PAH biodegradation.

关键词： biodegradation the Daliao River microcosm polycyclic aromatic hydrocarbon sediment

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Scale effects of leaf area index inversion based on environmental and disaster monitoring satellite data

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Science China Earth Sciences 2010年第S1期53卷 92-98页

作者： ZHANG Hao1,LI XiaoWen1,2,CAO ChunXiang1,YANG Hua2,GAO MengXu1,3,ZHENG Sheng1,3,XU Min1,3,XIE DongHui2,JIA HuiCong1,JI Wei1,ZHAO Jian1,3,CHEN Wei1,3 & NI XiLiang1,3 1 State key laboratory of Remote Sensing Science,Jointly Sponsored by Institute of Remote Sensing Applications,Chinese Academy of Sciences and beijing normal university,beijing 100101,China 2 State key laboratory of Remote Sensing Science,Jointly Sponsored by beijing normal university and Institute of Remote Sensing Applications of Chinese Academy of Sciences,beijing 100875,China 3 Graduate university of Chinese Academy of Sciences,beijing 100049,China 1. State key laboratory of Remote Sensing Science Jointly Sponsored by Institute of Remote Sensing Applications Chinese Academy of Sciences and Beijing Normal University Beijing 100101 China2. State Key Laboratory of Remote Sensing Science Jointly Sponsored by Beijing Normal University and Institute of Remote Sensing Applications of Chinese Academy of Sciences Beijing 100875 China3. Graduate University of Chinese Academy of Sciences Beijing 100049 China

The spatial distribution of sub-pixel components has an impact on retrieval accuracy,and should be accounted for when inverting a three-dimensional adiative transfer model to retrieve leaf area index(LAI).To investigate this effect,we constructed three realistic scenarios with the same LAI values and other properties,except that the simulated plants had different *** implemented the radiosity method to subsequently produce synthetic bidirectional reflectance factor(BRF) datasets based upon these simulated *** inversion was conducted using these data,which showed that spatial distribution affects retrieval *** inversion was also conducted for LAI based on charge-coupled device(CCD) data from the Environment and Disaster Monitor Satellite(HJ-1),which depicted both forest and drought-resistant crop land *** showed that heterogeneity in coarse-resolution remote sensing data is the main error source in LAI *** spatial distribution of global fractal dimension index,which can be used to describe the area of sub-pixel components and their spatial distribution modes,shows good consistency with the coarse resolution LAI inversion error.

关键词： HJ-1 leaf area index scale effect spatial distribution

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A preliminary knowledge-driven prediction model of snail distribution in the Poyang Lake region

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Chinese Science Bulletin 2008年第1期53卷 115-123页

作者： ZHAO An1,2,3 & BAO ShuMing1 1 The key Lab of Poyang Lake Ecological Environment and Resource Development, Jiangxi normal university, Nanchang 330022, China 2 Institute of Geographic Sciences and Resources Research, Chinese Academy of Sciences, beijing 100101, China 3 School of geography and Environmental Sciences, Jiangxi normal university, Nanchang 330022, China The key Lab of Poyang Lake Ecological Environment and Resource Development Jiangxi Normal University Nanchang China Institute of Geographic Sciences and Resources Research Chinese Academy of Sciences Beijing China School of geography and Environmental Sciences Jiangxi Normal University Nanchang China

Present monitoring and prediction of schistosomiasis’s intermediate parasite, snail, are based on re-mote sensing image’s spectral signatures, and the calculation result is in fact an incom-plete-constraints solution. TM image of the Poyang Lake region on October 31, 2005 was combined with GIS thematic data (DEM, boundary of the Poyang Lake, vegetation, soil and land use) to make a prediction on snail spatial distribution in the region by remote sensing, geo-informatics and knowl-edge-driven modeling according to mechanism of snail occurrence. Result shows that with change of overall fuzzy membership of snail occurrence from high to low, snail occurrence of the snail samples of validation group goes up to 81% within 10% high fuzzy membership range, denoting high efficiency of the model in predicting snail occurrence.

关键词：鄱阳湖区域蜗牛分布模糊分类血吸虫病

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Characteristics of energy dissipation in hyperconcentrated flows

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International Journal of Sediment Research 2008年第4期23卷 387-397页

作者： An-ping SHU 1,Qing-quan LIU2,Yu-jun YI 3,and Zhi-dong ZHANG 41 Assoc.Prof.,School of Environment,key laboratory of Water and Sediment Sciences of Ministry of Education,beijing normal university,beijing 100875,China2 Prof.,Institute of Mechanics,Chinese Academy of Sciences,beijing 100080,China3 Lecturer,Dr.,School of Environment,beijing normal university,beijing 100875,China4 Graduate student,School of Environment,beijing normal university,beijing 100875,China [a]Assoc. Prof. School of Environment key laboratory of Water and Sediment Sciences of Ministry of Education beijing normal university beijing 100875 China [b]Prof. Institute of Mechanics Chinese Academy of Sciences beijing 100080 China [c]Lecturer Dr. School of Environment beijing normal university beijing 100875 China. The project is supported by the National Natural Science Foundation of China (Grant No. 10672024) [d]Graduate student School of Environment beijing normal university beijing 100875 China

An equilibrium equation for the turbulence energy in sediment-laden flows was derived on the basis of solid–liquid two-phase flow theory. The equation was simplified for two-dimensional, uniform, steady and fully developed turbulent hyperconcentrated flows. An energy efficiency coefficient of suspended-load motion was obtained from the turbulence energy equation, which is defined as the ratio of the sediment suspension energy to the turbulence energy of the sediment-laden flows. laboratory experiments were conducted to investigate the characteristics of energy dissipation in hyperconcentrated flows. A total of 115 experimental runs were carried out, comprising 70 runs with natural sediments and 45 runs with cinder powder. Effects of sediment concentration on sediment suspension energy and flow resistance were analyzed and the relation between the energy efficiency coefficient of suspended-load motion and sediment concentration was established on the basis of experimental data. Furthermore, the characteristics of energy dissipation in hyperconcentrated flows were identified and described. It was found that the high sediment concentration does not increase the energy dissipation; on the contrary, it decreases flow resistance.

关键词： Hyperconcentrated flows Turbulence energy Efficiency coefficient Energy dissipation

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Risk assessment and validation of flood disaster based on fuzzy mathematics

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Progress in Natural Science:Materials International 2009年第10期19卷 1419-1425页

作者： Weiguo Jiang a,b,Lei Denga,b,Luyao Chenc,Jianjun Wu a,b,Jing Lia,b a key laboratory of Environment Change and Natural Disaster,MOE,beijing normal university,beijing 100875,China b Academy of Disaster Reduction and Emergency Management,MOCA&MOE,beijing normal university,beijing 100875,China c Department of geography,Texas A&M university,College Station,TX 77843-3147,USA [a]key laboratory of Environment Change and Natural Disaster MOE Beijing Normal University Beijing 100875 China [b]Academy of Disaster Reduction and Emergency Management MOCA&MOE Beijing Normal University Beijing 100875 China [c]Department of geography Texas A&M University College Station TX 77843-3147 USA

Floods often take place around rivers and plains,which indicates a higher risk of flooding in these *** paper adopts fuzzy comprehensive assessment(FCA),simple fuzzy classification(SFC),and the fuzzy similarity method(FSM) to assess flood disaster risk in Kelantan,*** data,such as the flooded area,paddy area,urban area,residential area,and refuges,were overlaid to validate and analyze the accuracy of flood disaster *** results show that(1) 70-75% of flooded areas lie within the higher and high-est risk zones,which shows an effective assessment accuracy;(2) paddy,built-up,and residential areas concentrated in the higher and highest risk zones are more likely to be destroyed by flood disasters;(3) 200-225 refuges in the higher and highest risk zones account for around 50% of all refuges,which means that more refuges should be built in the higher and highest risk zones to meet the accommodation requirement;(4) three methods proved to be feasible and effective in evaluating flood disaster risk,among which FCA is more suitable for the study area than the two other methods.

关键词： Flood disaster Risk assessment Risk validation Fuzzy mathematics Malaysia

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Complete multiple round quantum dense coding with quantum logical network

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Chinese Science Bulletin 2007年第9期52卷 1162-1165页

作者： LI ChunYan1,2,LI XiHan1,2,DENG FuGuo1,2,3,ZHOU Ping1,2 & ZHOU HongYu1,2,3 1 key laboratory of Beam Technology and Material Modification of Ministry of Education,beijing normal university,beijing 100875,China 2 Institute of Low Energy Nuclear Physics,and Department of Material Science and Engineering,beijing normal university,beijing 100875,China 3 beijing Radiation Center,beijing 100875,China key laboratory of Beam Technology and Material Modification of Ministry ofEducation Beijing Normal University Beijing 100875 China

We present a complete multiple round quantum dense coding scheme for improving the source ca-pacity of that introduced recently by Zhang et al. The receiver resorts to two qubits for storing the four local unitary ope... 详细信息

关键词：量子通信多重量子紧凑编码量子逻辑网络量子纠缠

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Collision dynamics of He@C_(60)+He@C_(60) at low energies

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Science China(Physics,Mechanics & Astronomy) 2008年第7期51卷 765-772页

作者： ZHAO Qiang1,2, ZHANG FengShou1,2,3 & ZHOU HongYu1,2 1 key laboratory of Beam Technology and Material Modification of Ministry of Education, Institute of Low Energy Nuclear Physics, beijing normal university, beijing 100875, China 2 beijing Radiation Center, beijing 100875, China 3 Center of Theoretical Nuclear Physics, National laboratory of Heavy Ion Accelerator of Lanzhou, Lanzhou 730000, China 1. key laboratory of Beam Technology and Material Modification of Ministry of Education Institute of Low Energy Nuclear Physics Beijing Normal University Beijing 100875 China 2. beijing Radiation Center Beijing 100875 China 3. Center of Theoretical Nuclear Physics National Laboratory of Heavy Ion Accelerator of Lanzhou Lanzhou 730000 China

A semi-empirical molecular dynamics model is developed. The central collisions of C60+C60 and He@C60+He@C60 at different incident energies are investigated based on this model. It is found that the dimer structures have been produced at proper incident energies and these fullerene dimers could be formed by a self-assembly of C60 fullerene and He@C60. The He atom has a significant effect at higher incident energy and this embedded He atom can enhance the stability of the dimer structure.

关键词： C60 He@C60 collision molecular dynamics

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Entropy product measure for multipartite pure states

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Science China(Physics,Mechanics & Astronomy) 2006年第5期49卷 606-615页

作者： CAO Wancang1,2, LIU Dan2, PAN Feng3 & LONG Guilu2,4 1. Department of Physics, Chifeng College, Chifeng 024001, China 2. key laboratory for Quantum Information and Measurements, Department of Physics, Tsinghua university, beijing 100084, China 3. Department of Physics, Liaoning normal university, Dalian 116029, China 4. key laboratory for Atomic and Molecular Nano-Sciences, Tsinghua university, beijing 100084, China Correspondence should be addressed to Long Guilu Department of Physics Chifeng College Chifeng 024001 China key laboratory for Quantum Information Measurements Department of Physics Tsinghua University Beijing 100084 China Department of Physics Liaoning Normal University Dalian 116029 China key laboratory for Atomic Molecular Nano-Sciences Tsinghua University Beijing 100084 China

An entanglement measure for multipartite pure states is formulated using the product of the von Neumann entropy of the reduced density matrices of the constituents. Based on this new measure, all possible ways of the maximal entanglement of the triqubit pure states are studied in detail and all types of the maximal entanglement have been compared with the result of ‘the average entropy’. The new measure can be used to calculate the degree of entanglement, and an improvement is given in the area near the zero entropy.

关键词： multipartite pure state von Neumann entropy entanglement measure

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Estimation of suspended sediment concentration based on bio-optical mechanism and HJ-1 image in Chaohu Lake

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Science China Earth Sciences 2010年第S1期53卷 58-66页

作者： WANG Qiao1,2,JIN Xin2,LI YunMei2,WU ChuanQing1,Lü Heng2,WANG YanFei2,ZHANG Hong2,YIN Bin2 & ZHU Li1 1Satellite Environment Center,Ministry of Environmental Protection,beijing 100029,China 2key laboratory of Virtual Geographic Environment of Education Ministry,Nanjing normal university,Nanjing 210046,China 1. Satellite Environment Center Ministry of Environmental Protection Beijing 100029 China2. Key Laboratory of Virtual Geographic Environment of Education Ministry Nanjing Normal University Nanjing 210046 China

Synchronization experiment was conducted in June,2009 to get Inherent Optical Properties(IOP) of water component in Chaohu *** bio-optical mechanism was studied combined with multispectral data of Environmental Satellite 1(CCD),and then inversion models of total suspended matter(TSM),inorganic suspended matter(ISM) and organic suspended matter(OSM) concentration were *** data indicated that:the absorption ratio of suspended particulate matter and CDOM to total were almost no change from band 1 to band 2 with about 85% and 9%,*** ratio of pure water to total increased from 0.4% to 5.6%.Water reflectance in these two bands were influenced by absorption of three kinds of components:algae particles absorption surpassed non-algal particles in band 3,and so played an important role in total absorption with about 35.7%;the proportion of pure water absorption and particles matter backscattering both were 99% in band 4,so these two components decided the main inherent optical properties in band *** models of TSM and ISM concentration inversion based on band combination(band 3 + band 4)/(band 1 + band 2) were built,while OSM concentration was estimated by band 4/(band 1 + band 2) *** by image data,RE of TSM concentration between modeled and measured was 33.4%,and RMSE was 18.68 mg/*** of ISM and OSM concentration were 39.9% and 35.2% *** inversion was more accurate when satellite-ground data were just in the same *** this situation,RE of ISM concentration dropped to 25.4%,and that of TSM and OSM reduced to 26.5% and 26.8% as well.

关键词： HJ-1 Satellite bio-optical property Chaohu Lake suspended matter

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