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An improved imaging algorithm for fixed-receiver bistatic SAR

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Science China(Information sciences) 2010年第7期53卷 1461-1469页

作者： GENG XuPu1,2.3. HU YingHui1,2. YAN HongHui2.& WANG YanFei2.1graduate {2. of the Chinese academy of {3., beijing 10003., China 2.nstitute of Electronics, Chinese academy of {3., beijing 100190, China 3.7} Institute of Environment Features, beijing 100854, China 1. graduate school of the Chinese {2. of {3. Beijing 100039 China2. Institute of Electronics Chinese Academy of Sciences Beijing 100190 China3. Beijing Institute of Environment Features Beijing 100854 China

Based on the signal model of fixed-receiver bistatic SAR, this paper analyzes the characteristics of azimuth-variant, which includes variation of range migration curve and variation of Doppler rate caused by different azimuth position of targets. Then, an extended nonlinear chirp scaling (NLCS) algorithm is proposed, with its flowchart and phase compensation functions being provided. Simulation results show that the algorithm is available for the characteristics of azimuth-variant of fixed-receiver bistatic SAR, and good focused radar images could be acquired.

关键词： synthetic aperture radar (SAR) bistatic SAR fixed-receiver characteristics of azimuth-variant range cell migration correction (RCMC)

Monitoring of rice crop using ENVISAT ASAR data

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Science China Earth sciences 2006年第7期49卷 755-763页

作者： DONG Yanfang1, 2. SUN Guoqing1,3.& PANG Yong4 1. State Key Laboratory of Remote Sensing Science, Institute of Remote Sensing Applications, Chinese academy of {2., beijing 100101, China 2. {3. University of Chinese academy of {2., beijing 10003., China 3. Department of Geography, University of Maryland, College Park, MD 2.742. USA 4. Forest Remote Sensing Lab, Research Institute of Forest Resource and Information Technology, Chinese academy of For-estry, beijing 100091, China 1. State Key Laboratory of Remote Sensing Science Institute of Remote Sensing Applications Chinese Academy of Sciences Beijing 100101 China 2. graduate University of Chinese academy of {2. Beijing 100039 China 3. Department of Geography University of Maryland College Park MD 20742 USA 4. Forest Remote Sensing Lab Research Institute of Forest Resource and Information Technology Chinese Academy of Forestry Beijing 100091 China

Because of the cloudy conditions during the rice growth period, rice is one of the agri-cultural crops most suited to monitoring with the SAR instruments. Backscatter response measured by SAR is correlated with rice conditions, including height, density, biomass and structure, which are variable at different growing stages. In this paper, multi-date ENVISAT ASAR Alternating Polarization Mode (APMode) imageries were acquired during the rice crop growing cycle. At the same time, the rice parameters were measured in field. A continuous canopy model was used to compute the back-scattering from rice fields during the growth cycle, and the relationship between rice parameters and radar backscattering coefficients from both ASAR and modeling was analyzed. The effects of polari-zation, incidence angle and polarization on radar backscattering coefficients were analyzed. It was found that simulated radar backscatter has similar trends as ASAR data. This will be meaningful for the further research of rice parameters estimation from ASAR data. Different features show signifi-cantly different signatures in ASAR images and they follow some certain laws, so rice area can be accurately mapped by using multi-temporal SAR images, then rice yield can be estimated.

关键词： rice, ASAR, radar backscattering, model.

Algebraically explicit analytical solu-tions for the unsteady non-Newtonian swirling flow in an annular pipe

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Science China(Physics,Mechanics & Astronomy) 2006年第4期49卷 396-400页

作者： CAI Ruixian1 & GOU Chenhua1,2.1. Institute of Engineering Thermophysics, Chinese academy of sciences, {2. 100080, China 2. {3. school, Chinese academy of sciences, {2. 100080, China 1. Institute of Engineering Thermophysics Chinese Academy of Sciences Beijing 100080 China 2. graduate school Chinese Academy of Sciences Beijing 100080 China

This paper presents two algebraically explicit analytical solutions for the incompressible unsteady rotational flow of Oldroyd-B type in an annular pipe. The first solution is derived with the common method of separation of variables. The second one is deduced with the method of separation of variables with addition developed in recent years. The first analytical solution is of clear physical meaning and both of them are fairly simple and valuable for the newly developing computational fluid dynamics. They can be used as the benchmark solutions to verify the applicability of the existing numerical computational methods and to inspire new differencing schemes, grid generation ways, etc. Moreover, a steady solution for the generalized second grade rheologic fluid flow is also presented. The correctness of these solutions can be easily proven by substituting them into the original governing equation.

关键词： analytical solution, Oldroyd-B type fluid, swirling flow, non-Newtonian.

Distribution characteristics of magnetic susceptibility of the surface sediments in the southern Yellow Sea

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Chinese Science Bulletin 2003年第B06期48卷 37-41页

作者： GE Shulan~(1,2.3., SHI Xuefa~1 & HAN Yibing~1 1. Key Laboratory of Marine Sedimentology and Environmental Geology, First Institute of Oceanography, State Oceanic Administration. Qingdao 2.6061. China 2. Institute of Geology and Geophysics, Chinese academy of {2., beijing 10002.. China 3. {3. school. Chinese academy of {2., beijing 10003.. China 1. Key Laboratory of Marine Sedimentology and Environmental Geology First Institute of Oceanography State Oceanic Administration 266061 Qingdao China 2. Institute of Geology and Geophysics Chinese Academy of Sciences 100029 Beijing China 3. graduate {2. Chinese Academy of Sciences 100039 Beijing China

The characteristic distributions of magnetic susceptibility (MS) are analyzed on the basis of susceptibility of 172.surface sediment samples in the southern Yellow Sea (SYS). The preliminary results are as follows: first, the distributions clearly correspond to different modern sediment assemblages in the continental sea, which indicates different sediment origins. With the 3. μCGS isoline being taken as demarcation line, the study area can then be divided into section H (high MS value area) and section L (low MS value area). Section H is mainly adjacent to land with two main sources of the Changjiang River and the Huanghe *** L is mainly an eddy sediment area, where Yellow Sea Cold Water is entrenched all the year round. The distribution pattern of MS could tell apart strong or weak hydrodynamic conditions and has a close relation to the circulation system in this area. At the areas of the SYS Circumfluent and northern East China Sea (NECS) Circumfluent (weak hydrodynamic), the MS has low values, while in the areas of Coastal Current (strong hydrodynamic), the values are *** the same time, the oxidizing areas tend to take on higher MS, while the reducing areas have lower one. It seems safe to say that the MS in the continental sea reflects more of the sediment origin and sedimentary environment, which is different from that of loess, lake and surface soil as a climate proxy.

关键词：中国黄海表面沉积物磁化率等值线长江黄河旋涡沉积区循环系统

The relation between black hole masses and Lorentz factors of the jet components in blazars

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Research in Astronomy and Astrophysics 2009年第3期9卷 293-301页

作者： Ming Zhou1,2.3.and Xin-Wu Cao1,2.1 Shanghai Astronomical Observatory, Chinese academy of {2., Shanghai 2.003., China 2.Joint Institute for Galaxy and Cosmology (JOINGC) of SHAO and USMC, Shanghai 2.003., China 3.graduate {3. of the Chinese academy of {2., beijing 100049, China Shanghai Astronomical Observatory Chinese Academy of Sciences Shanghai 200030 China Joint Institute for Galaxy and Cosmology (JOINGC) of SHAO and USMC Shanghai 200030 China graduate school of the Chinese {2. of {3. Beijing 100049 China

We explore the relationship between black hole mass (MBH) and the motion of the jet components for a sample of blazars. The Very Long Baseline Array (VLBA) 2.cm Survey and its continuation: Monitoring of Jets in active galactic nuclei (AGNs) with VLBA Experiments (MOJAVE) have observed 2.8 radio-loud AGNs, of which 146 blazars have reliable measurements of their apparent velocities of the jet components. We calculate the minimal Lorentz factors for these sources from their measured apparent velocities, and their black hole masses are estimated with their broad-line widths. A sig- nificant intrinsic correlation is found between black hole masses and the minimal Lorentz factors of the jet components. The Eddington ratio is only weakly correlated with the min- imal Lorentz factor, which may imply that the Blandford-Znajek (BZ) mechanism may dominate over the Blandford-Payne (BP) mechanism for the jet acceleration (at least) in blazars.

关键词： black hole physics — galaxies: active — galaxies: jets — galaxies: nuclei

Discovery of Cu-Zn,Cu-Sn intermetallic minerals and its significance for genesis of the Mianning-Dechang REE Metallogenic Belt,Sichuan Province,China

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Science China Earth sciences 2006年第6期49卷 597-603页

作者： XIE Yuling1, HOU Zengqian2. XU Jiuhua1, YUAN Zhongxin2. BAI Ge2.& LI Xiaoyu3.1. Civil and Environmental Engineering school, University of Science and Technology {2., {2. 100083. China 2. Institute of Geology, Chinese {3. of Geological sciences, beijing 10003., China 3. The 109th Geological Team, Sichuan Bureau of Mineral Exploration, Chengdu 610100, China 1. Civil and Environmental Engineering school University of Science and Technology Beijing Beijing 100083 China 2. Institute of Geology Chinese Academy of Geological Sciences Beijing 100037 China 3. The 109th Geological Team Sichuan Bureau of Mineral Exploration Chengdu 610100 China

Mianning-Dechang Himalayan REE Metallogenetic Belt in Sichuan Province lies along the western margin of the Yangtze Craton. We have conducted detailed mineralogical studies on ore minerals collected from Maoniuping and Dalucao, the two largest deposits in the belt. With optical microscope, SEM/EDS, and EPMA, three rare intermetallic minerals, i.e., zinccopperite (Cu2.n), Sn- bearing native copper, and Cu-bearing jupiter were found to occur in the main ore along with barite, fluorite, apatite, sulfide and bastnaesite. Since the conditions under which zinccopperite and Sn- bearing native copper formed are quite unique, finding of these minerals, for the first time in domestic REE deposits, has significant implications for the genesis of the ore deposits in which they occur. In comparison with Cu-Zn intermetallic minerals in other occurrences, we propose that the formation of this REE metallogenetic belt is associated with fast upwelling of the Himalayan magma from deep source.

关键词： Mianning-Dechang REE metallogenetic belt, Cu-bearing intermetallic minerals, EPMA, genesis significance, deep source magmatic activity.

De-interlacing technique based on total variation with spatial-temporal smoothness constraint

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Science in China(Series F) 2007年第4期50卷 561-575页

作者： YIN XueMin1,2.3. YUAN JianHua1,2. LU XiaoPeng1,2.& ZOU MouYan1,2.1 Institute of Electronics, Chinese academy of {2., beijing 100080, China 2.{3. school, Chinese academy of {2., beijing 10003., China 3.Jiuquan Satellite Launch Center, Lanzhou 73.750, China 1. Institute of Electronics Chinese Academy of Sciences Beijing 100080 China 2. graduate school Chinese Academy of Sciences Beijing 100039 China 3. Jiuquan Satellite Launch Center Lanzhou 732750 China

This paper introduces a new method of converting interlaced video to a progressively scanned video and image, The new method is derived from Bayesian framework with the spatial-temporal smoothness constraint and the MAP is done by minimizing the energy functional, The half-quadratic regularization method is used to solve the corresponding partial differential equations （PDEs）, This approach gives the improved results over the conventional de-interlacing methods, Two criteria are proposed in the paper, and they can be used to evaluate the performance of the de-interlacing algorithms,

关键词： video processing de-interlacing total variation spatio-temporai smoothness constraint PDEs half-quadratic regularization

Improvement of the SLP simulation in the coupled AGCM-ocean surface wave model

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Chinese Science Bulletin 2005年第20期50卷 2397-2400页

作者： YU Weidong1, 2. 3. LI Zhaoxin4 & YUAN Yeli3.1. Institute of Oceanology, Chinese {2. of sciences, Qingdao 2.6071, China 2. graduate {3. of Chinese {2. of sciences, beijing 100049, China 3. Laboratory of Marine Science and Numerical Modeling, First Institute of Oceanography, State Oceanic Administration, Qingdao 2.6061, China 4. LMD/CNRS, Univ. Paris 6, Paris, France Institute of Oceanology Chinese Academy of Sciences Qingdao 266071 China graduate school of Chinese {2. of {3. Beijing 100049 China Laboratory of Marine Science and Numerical Modeling First Institute of Oceanography State Oceanic Administration Qingdao 266061 China LMD/CNRS Univ. Paris 6 Paris France

The coupled atmosphere-ocean general circulation models (CGCM) are nowbecoming the indispensable tools for the climate study. However, most models still suffer fromunrealistic simulations. One problem is the troublesome climate drift. It may come from someunresolved aspects. One possibility is the poor air-sea surface flux description now adopted inCGCM. The commonly used solution for this problem is the so-called flux correction. To deal with it,Hasslemann proposed an alternative solution of prospect. That is to incorporate the ocean surfacewave model into this coupled GCM system so as to establish a coupled atmosphere-wave-ocean *** necessity is clearly seen from the recent field experiment that air-sea momentum flux dependsstrongly on the sea state. So the explicit calculation of the air-sea flux with the aid of the oceansurface wave model is highly desired. Theoretical progress has provided feasibility to such ideaand experiments have been conducted. Recent work also reveals that coupling ocean surface wave modelwith oceanic general circulation model can result in much better reproduction of the upper oceanthermal structure. This further strengthens our belief in the final realization of the coupledatmosphere-wave-ocean modeling system.

关键词：大气海洋循环模式气象学 SLP模拟

Monitoring the Cultivated Slope Land in the Three Gorges Reservoir Area Based on Remote Sensing and GIS

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Wuhan University Journal of Natural sciences 2006年第4期11卷 915-921页

作者： ZHOU Jieming1, ZHOU Qigang 2. 3.,HUANG Zhiqin 2. 3. 4 1. The Faculty of Geography and Resources Science, Sichuan Normal University, Chengdu 610066, Sichuan, China 2. Institute of Mountain Hazards and Environment, Chinese {2. of sciences, Chengdu 610041, Sichuan, China 3. graduate University of the Chinese {2. of sciences, beijing 100049, China 4. Information Center of Land and Resources Department of Sichuan Province, Chengdu 610041, Sichuan, China The Faculty of Geography Resources Science Sichuan Normal University 610066 Chengdu Sichuan China Institute of Mountain Hazards Environment Chinese Academy of Sciences 610041 Chengdu Sichuan China graduate University of the Chinese academy of {2. 100049 Beijing China Information Center of Land Resources Department of Sichuan Province 610041 Chengdu Sichuan China

By means of combining auto-extraction with manual interpretation, the current distribution information about cultivated land is obtained. The distribution information of 1992.is extracted from the dynamic polygons of 2.02. The monitoring mini-system of the cultivated slope land is established. In the system, detailed surveys, focused on the resources of cultivated slope land, are carried out. The results indicate that the area of the cultivated slope land is very large. Meanwhile, there are lots of cultivated steep slopes with gradient above 3.°. The areas of steep land cultivated had been slowly reduced from 1992.to 2.02. At the same time, the pressures of returning farm land to forestry are great in all counties. The conflicts between population growth, insufficient grain supply and stagnant economic development sharpen increasingly. It is inevitable to improve the agricultural structure.

关键词： slope land cultivated remote sensing geography information system (GIS) the pressure of returning farm land to forestry Three Gorges Reservoir Area