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Study on the algorithm to Retrieve Precipitation with X-Band Synthetic Aperture Radar

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Acta meteorologica Sinica 2010年第5期24卷 614-621页

作者：谢亚楠还剑平陶阳 School of Communication and Information Engineering Shanghai University University of Maryland

In order to obtain the global precipitation distribution data,this paper investigates the precipitation distribution model,the normalized radar cross-section model,and the retrieval algorithm with X-band synthetic aperture radar（X-SAR）.A new retrieval algorithm based on the surface-scattering reference attenuation is developed to retrieve the rain rate above the ground *** new algorithm needs no statistical work load and has more extensive *** using the new algorithm for three cases verify that the rainfall is retrieved with high precision,which proves the capability of the algorithm.

关键词： microwave remote sensing precipitation retrieval algorithm X-band synthetic aperture radar(X-SAR)

Variation of Antarctic marginal ice zone extent (1989-2019)

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Advances in Polar Science 2021年第4期32卷 341-355页

作者： WANG Miaojiang LIU Tingting YANG Zijian WU Bing ZHU Xueming Changzhou Xinbei Natural Resources and Planning Technical Support Center Changzhou 213001China Chinese Antarctic Center of Surveying and Mapping Wuhan UniversityWuhan 430072China

The Antarctic marginal ice zone(MIZ)is the transition region between open water and consolidated pack ice,which is defined as an area with 15%-80%sea ice *** MIZ represents the outer circle of Antarctic sea ice and the biological activity circle of Antarctic organisms,which provides a direct indication of the extent of Antarctic sea *** this study,the joint total variation and nonnegative constrained least square algorithm are applied to retrieve the Antarctic MIZ extent based on passive microwave data sets from 1989 to *** spatial and temporal variations of the Antarctic MIZ extent and five regions are *** results show that the Antarctic MIZ extent follows a strong monthly variation pattern,decreasing from November to February and increasing from March to *** annual MIZ extent is largest in the Weddell Sea and smallest in the Western Pacific *** edge of the sea ice begins to form a closed ring in May,which eventually closes near the Antarctic *** ring width variation is large in summer,but generally stabilizes between 350 and 370 km in *** average latitude of the Antarctic MIZ is relatively stable in summer,but changes substantially in winter with a difference of approximately 3°.In October,the lowest mean latitude of the MIZ can reach 64.35°*** sea surface pressure,2-m temperature,and 10-m wind speed are negatively correlated with the MIZ extent variation,among which the second-order partial correlation coefficient of the sea surface pressure and MIZ extent is−0.8773 in the Western Pacific Ocean.

关键词： Antarctic marginal ice zone passive microwave data retrieval algorithm correlation analysis variation

Water quality monitoring in a slightly-polluted inland water body through remote sensing-Case study of the Guanting Reservoir in Beijing,China

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Frontiers of Environmental Science & Engineering 2008年第2期2卷 163-171页

作者： Weiqi HE Shan CHEN Xuehua LIU Jining CHEN Department of Environmental Science and Engineering Tsinghua UniversityBeijing 100084China Research Center for Eco-environmental Science Chinese Academy of SciencesBeijing 100085China

This study focused on the water quality of the Guanting Reservoir,a possible auxiliary drinking water source for *** a remote sensing(RS)approach and using Landsat 5 Thematic Mapper(TM)data,water quality retrieval models were established and analyzed for eight common water quality variables,including algae content,turbidity,and concentrations of chemical oxygen demand,total nitrogen,ammonia nitrogen,nitrate nitrogen,total phosphorus,and dissolved *** results show that there exists a statistically significant correlation between each water quality variable and remote sensing data in a slightly-polluted inland water body with fairly weak spectral *** an appropriate method of sampling pixel digital numbers and multiple regression algorithms,retrieval of the algae content,turbidity,and nitrate nitrogen concentration was achieved within 10% mean relative error,concentrations of total nitrogen and dissolved phosphorus within 20%,and concentrations of ammonia nitrogen and total phosphorus within 30%.On the other hand,no effective retrieval method for chemical oxygen demand was *** accuracies were acceptable for the practical application of routine monitoring and early warning on water quality safety with the support of precise traditional *** results show that performing the most traditional routine monitoring of water quality by RS in relatively clean inland water bodies is possible and effective.

关键词： Guanting Reservoir Landsat Thematic Mapper(TM) remote sensing(RS) water quality retrieval algorithm drinking water source linear regression

A New Global Solar-induced Chlorophyll Fluorescence(SIF)Data Product from TanSat Measurements

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维普期刊数据库

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Advances in Atmospheric Sciences 2021年第3期38卷 341-345页

作者： Lu YAO Dongxu YANG Yi LIU Jing WANG Liangyun LIU Shanshan DU Zhaonan CAI Naimeng LU Daren LYU Maohua WANG Zengshan YIN Yuquan ZHENG Key Laboratory of Middle Atmosphere and Global Environment Observation Institute of Atmospheric PhysicsChinese Academy of SciencesBeijing 100029China University of Chinese Academy of Sciences Beijing 100049China Shanghai Advanced Research Institute Chinese Academy of SciencesShanghai 201210China Key Laboratory of Digital Earth Science Institute of Remote Sensing and Digital EarthChinese Academy of SciencesBeijing 100094China National Satellite Meteorological Center China Meteorological AdministrationBeijing 100081China Changchun Institute of Optics Fine Mechanics and PhysicsChangchun 130033China Shanghai Engineering Center for Microsatellites Shanghai 201210China

The Chinese Carbon Dioxide Observation Satellite Mission(TanSat)is the third satellite for global CO2 monitoring and is capable of detecting weak solar-induced chlorophyll fluorescence(SIF)signals with its advanced technical *** on the Institute of Atmospheric Physics Carbon Dioxide retrieval algorithm for Satellite Remote Sensing(IAPCAS)platform,we successfully retrieved the TanSat global SIF product spanning the period of March 2017 to February 2018 with a physically based *** paper introduces the new TanSat SIF dataset and shows the global seasonal SIF maps.A brief comparison between the IAPCAS TanSat SIF product and the data-driven SVD(singular value decomposition)SIF product is also performed for follow-up algorithm *** comparative results show that there are regional biases between the two SIF datasets and the linear correlations between them are above 0.73 for all *** future SIF data product applications and requirements for SIF space observation are discussed.

关键词： TanSat solar-induced chlorophyll fluorescence retrieval algorithm remote sensing

RETRIEVING OVER-OCEAN PRECIPITABLE WATER FROM THE SSM/I MEASUREMENTS WITH SEVERAL REGRESSION algorithmS

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Acta meteorologica Sinica 1998年第4期12卷 443-449页

作者：陈洪滨孙海冰王普才吕达仁 LAGEO Institute of Atmospheric PhysicsChinese Academy of Sciences.Beijing 100029

A collocated SSM/I and radiosonde measurement data set provided by the NASDA(Japan) was used to retrieve the total precipitable water(PW)over *** retrieval results obtained with several regression algorithms were compared against the radiosonde *** is shown that:(a)the routinely operational algorithm of Alishouse et al.(1990)yields significant underestimation in high PW regime and overestimation in low PW regime;(b)a cubic correction by Colton and Poe(1994)is not sufficient and globally improves slightly the retrieval results;and (c)the regression algorithm with the form of brightness temperature(T_b)function In (280-T_b) gives a little largely scattered retrievals in whole PW range but without considerable over-and underestimates in low and high PW *** improve the estimation of the oceanic precipitable water from the SSM/I measurements,a composite algorithm with different forms of T_b function in *** and high PW regimes is proposed and tested.

关键词： precipitable water SSM/I(Special Sensor Microwave/Imager) retrieval algorithm

Data Mining and Neural Network Techniques in Case Based System

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Wuhan University Journal of Natural Sciences 2001年第Z1期6卷 601-605页

作者： Ni Zhi wei 1,2 , Cai Qing sheng 1, Li Long shu 2 1.Department of Computer Science, University of Science and Technology of China,Hefei 230027,China 2.The Key Laboratory of Intelligent Computing and Signal Processing ,Ministry of Education Department of Computer Science University of Science and Technology of China Hefei 230027 China

This paper first puts forward a case based system framework based on data mining techniques. Then the paper examines the possibility of using neural networks as a method of retrieval in such a case based system. In ... 详细信息

关键词： data mining neural network case based reasoning retrieval algorithm

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基于改进的颜色直方图模型的图像检索

基于改进的颜色直方图模型的图像检索