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Progress of Fengyun Meteorological Satellites Since 2020

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空间科学学报 2022年第4期42卷 724-732页

作者： ZHANG Peng XU zhe GUAN min XIE Lizi XIAN Di LIU Chang Key Laboratory of Radiometric Calibration and Validation for Environmental Satellites Beijing 100081 National Satellite Meteorological Center(National Center for Space Weather) Beijing 100081

China’s efforts to develop Fengyun meteorological satellites have made major strides over the past 50 years,with the polar and geostationary meteorological satellite series achieving continuously stable operation to persistently provide data and product services *** the end of 2021,19 Chinese self-developed Fengyun meteorological satellites have been launched *** of them are in operation at present,the data and products are widely applied to weather analysis,numerical weather forecasting and climate prediction,as well as environment and disaster *** the last COSPAR report,FY-4B,the first new-generation operational geostationary satellite,and FY-3E,the first early-morning orbit satellite in China’s polar-orbiting meteorological satellite family have been launched in *** characteristics of the two latest satellites and the instruments onboard are addressed in this *** status of current Fengyun Satellites,product and data service and international cooperation and supporting activities has been introduced as well.

关键词： Fengyun meteorological satellite Early morning orbit Product and data service International co-operation and supporting

SIMULATION OF BLOOD FLOW IN INTRACRANIAL ICA-PCOMA ANEURYSM VIA COMPUTATIONAL FLUID DYMAMICS MODELING

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Journal of Hydrodynamics 2009年第5期21卷 583-590页

作者： WANG Qing WANG Wei-zhe FEI Zhi-min LIU Ying-zheng CAO Zhao-min School of Mechanical Engineering Shanghai Jiao Tong University Shanghai 200240 China Renji Hospital Shanghai Jiao Tong University Shanghai 200001 China

In the present study, hemodynamics of the internal carotid artery-posterior communicating artery （ICA-PComA） was numerically modeled with CFD approach. The steady and pulsating blood flow in the ICA-PComA was simulated. The main concern was placed on the influence of aneurysm geometry on the local hemodynamics by changing the sac diameter and Aspect Ratio （AR） of the aneurysm. The numerical results show the significantly weakened Wall Shear Stress （WSS） and the intensified wall pressure in the aneurysm as AR is increased. Two factors, i.e., low WSS and high pressure of the aneurysm, may play important roles in the fragile change of the aneurysm and the final rupture. The distributions of Time-Averaged WSS （TAWSS）, Oscillatory Shear Index （OSI） and spatial WSS Gradients （WSSG）） were determined and discussed in view of their influences on the evolution of ICA-PComA aneurysm.

关键词： CFD intracranial aneurysm hemodynamics

A Large Chinese Text Dataset in the Wild

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Journal of Computer Science & Technology 2019年第3期34卷 509-521页

作者： Tai-Ling Yuan zhe Zhu Kun Xu Cheng-Jun Li Tai-Jiang Mu Shi-min Hu Department of Computer Science and Technology Tsinghua UniversityBeijing 100084China Department of Radiology Duke UniversityNorth Carolina 27708U.S.A. Tencent Technology(Beijing)Co.Ltd. Beijing 100080China

In this paper,we introduce a very large Chinese text dataset,in the *** optical character recognition(OCR)in document images is well studied and many commercial tools are available,the detection and recognition of text in natural images is still a challenging problem,especially for some more complicated character sets such as Chinese *** of training data has always been a problem,especially for deep learning methods which require massive training *** this paper,we provide details of a newly created dataset of Chinese text with about 1 million Chinese characters from 3850 unique ones annotated by experts in over 30 000 street view *** is a challenging dataset with good diversity containing planar text,raised text,text under poor illumination,distant text,partially occluded text,*** each character,the annotation includes its underlying character,bounding box,and six *** attributes indicate the charactcr's background complexity,appearance,style,*** the dataset,we give baseline results using state-of-the-art methods for tliree tasks:character recognition(top-1 accuracy of 80.5%),character detection(AP of 70.9%),and text line detection(AED of 22.1).The dataset,source code,and trained models are publicly available.

关键词： Chinese text dataset Chinese text detection Chinese text recognition

Hydrogen Bonds in Perovskite for Efficient and Stable Photovoltaic

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Chinese Journal of Chemistry 2024年第11期42卷 1284-1306页

作者： Tian-yun Wang Yang-yang Hao ming-zhe Zhu Guo-rui Cao Zhong-min Zhou College of Chemistry and Molecular Engineering Qingdao University of Science and TechnologyQingdaoShandong266042 China College of Chemical Engineering Qingdao University of Science and TechnologyQingdaoShandong266042 China

Owing to their distinctive optical and physical properties,organic-inorganic hybrid perovskite materials have gained significant attention in the field of electronic devices,especially solar *** achievement of high-performance solar cells hinges upon the utilization of top-notch perovskite thin ***,the fabrication process involving solutions and the polycrystalline nature of perovskite result in the emergence of numerous defects within the perovskite films,consequently exerting a deleterious influence on the overall performance and stability of the *** the performance and stability of perovskite solar cells by additive engineering to suppress/passivate defects is a viable approach,which involves hydrogen bond interactions in these device engineering *** review explores the intrinsic hydrogen bonds in methylammonium and formamidium lead triiodide,while also considering cation rotations,phase transitions,and ***,the review classifies additives into distinct categories,including organic small molecules,polymers,nanodots,classical salts,ionic liquids,and molten *** various forms and characterization techniques of hydrogen bonds are discussed,as well as their potential synergistic effects in conjunction with other chemical ***,this review offers insights into the potential utilization of hydrogen bonds to further enhance the performance and stability of devices.

关键词： Perovskite solar cells Hydrogen bond Additive Performance Stability Charge transfer Inhibition Cooperative effects

Individualized management of pregnant women with high hepatitis B virus DNA levels

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World Journal of Gastroenterology 2014年第34期20卷 12056-12061页

作者： Zhao Zhang Chao Chen zhe Li Ying-Hua Wu Xiao-min Xiao Department of Obstetrics and Gynecology The First Affiliated Hospital of Jinan University Zhuhai Entry-Exit Inspection and Quarantine Bureau

Hepatitis B is a major health concern in the Asia-Pacific region, and is endemic in China, Southeast Asia, and Africa. Chronic hepatitis B virus (HBV) infection may cause hepatic cirrhosis and liver cancer. It is estimated that there are more than 350 million chronic HBV carriers worldwide, of whom approximately one quarter will die of chronic hepatitis B-related liver diseases. HBV is transmitted horizontally through blood and blood products or by sexual transmission, and vertically from mother to infant. Perinatal infection is the predominant mode of transmission in countries with a high prevalence of hepatitis B surface antigen (HBsAg) carriage, and perinatal transmission leads to high rates of chronic infection. Therefore, it is important to prevent the mother-to-child transmission (MTCT) of HBV. Research has shown that pregnant women with high HBV DNA levels have an increased risk of MTCT. However, most of the obstetrics guidelines do not make a distinction between pregnant women with high HBV DNA levels and those who are HBsAg positive only. This review addresses the management of pregnant women with high levels of HBV viremia, in terms of antiviral therapy, use of hepatitis B immunoglobulin (HBIG), the combined application of hepatitis B vaccine and HBIG, choice of delivery mode and feeding practices. (C) 2014 Baishideng Publishing Group Inc. All rights reserved.

关键词： Hepatitis B virus Hepatitis B virus DNA High level Management Pregnancy

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我国主要地形上空理想定常流的流域分界分析

地球物理学报 2006年第4期49卷 971-982页

作者：王其伟谈哲敏南京大学中尺度灾害性天气教育部重点实验室南京大学大气科学系南京210093

本文根据旋转层结流体过山的基本理论,从总体上对影响我国天气、气候形成和发展的主要地形进行了动力学分析,定性地给出了中纬度典型的东西、南北向气流过我国主要地形的整体特征:以绕流还是爬流为主以及地形流动的准地转动力学性质.结... 详细信息

本文根据旋转层结流体过山的基本理论,从总体上对影响我国天气、气候形成和发展的主要地形进行了动力学分析,定性地给出了中纬度典型的东西、南北向气流过我国主要地形的整体特征:以绕流还是爬流为主以及地形流动的准地转动力学性质.结果表明我国地形大致可以分成三类:第一类是以爬流为主,满足准地转平衡动力学;第二类是以爬流为主,不满足准地转平衡动力学;第三类以绕流为主,不满足准地转动力学平衡.具体地形流动的整体特征取决于地形特征尺度、过山气流方向、地形高度以及地形的几何形状等.数值模拟的验证结果表明定性分析是可信的.

关键词：中国地形过山气流流动分界爬流绕流准地转动力学

NUMERICAL EVALUATION OF TWO-FLUID MIXING IN A SWIRL MICRO-MIXER

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Journal of Hydrodynamics 2006年第5期18卷 542-546页

作者： JIN Si-yu LIU Ying-zheng WANG Wei-zhe CAO Zhao-min KOYAMA Hide S. School of Mechanical and Power Engineering Shanghai Jiaotong University Shanghai 200030 China Department of Mechanical Engineering Tokyo Denki University Tokyo Japan

A collaborative investigation of two-fluid mixing in a swirl micro-mixer was carried out by the Shanghai Jiao Tong University and the Tokyo Denki University. Pure water and a mixture of glycerol and water were separately injected into branch channels and they were subsequently mixed in the central chamber. The two-fluid flow pattern was numerically modeled, in which the dependence of the mixture viscosity and density on the mass fraction of glycerol in the mixing fluid was carefully taken into consideration. The mixing performance of the two fluids was evaluated by varying the Reynolds numbers and the mass fractions of glycerol in water. The mixing process was extensively analyzed using streamline maps and contour plotting distributions of pressure and glycerol concentration. The numerical results show that the acceptable uniformity of mixing at Re = 0.1 is primarily attributed to the time-consuming molecular diffusion, whereas the cost-effective mixing at Re 〉 500 was obtained because of the generation of the swirling flow. The increasing mass fraction of glycerol in water was found to attenuate the mixing performance. The preliminary microscopic visualization of the two-fluid mixing at Re=1300 demonstrated the consistence with the numerical results.

关键词： two-fluid mixing micro-mixer numerical simulation

Wear Resistance and Bond Strength of Plasma Sprayed Fe/Mo Amorphous Coatings

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Journal of Iron and Steel Research International 2014年第10期21卷 969-974页

作者： Chao-ping JIANG Ya-zhe XING Feng-ying ZHANG Jian-min HAO Xu-ding SONG School of Materials Science and Engineering Chang'an University Key Laboratory of Road Construction Technology and Equipment MOE School of Construction MachineryChang'an University

Fe-based and Fe/Mo composite amorphous coatings were deposited on the surface of plain carbon steel substrates by atmospheric plasma spraying （APS）. With increasing the Mo alloy content, the microstructure of the coatings revealed more dense structure. The porosities of composite coating were all less than those of Fe-based coat- ing due to Mo alloy self-bonding performance. The ML10 friction and wear tester was employed to investigate the wear behaviors of the coatings under dry sliding conditions. It was found that the mass loss of the resultant coatings decreased with increasing Mo-based powders into the feedstock. This was attributed to the reduction of the delamina- tions resulting from improved intersplat bond with Mo addition.

关键词： atmospheric plasma spraying coating delamination wear bond strength

Using Quantile Regression Approach to Analyze Price Movements of Agricultural Products in China

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Journal of Integrative Agriculture 2012年第4期11卷 674-683页

作者： LI Gan-qiong XU Shi-wei LI zhe-min SUN Yi-guo DONG Xiao-xia Agricultural Information Institute Chinese Academy of Agricultural Sciences/Key Laboratory of Agri-information Service Technology Ministry of Agriculture/Key Laboratory of Digital Agricultural Early Warning Technology and System Chinese Academy of Agricultural Sciences Beijing 100081 P.R. China Department of Economics University of Guelph Ontario N1G2W1 Canada

This paper studies how the price movements of pork,chicken and egg respond to those of related cost factors in short terms in Chinese *** employ a linear quantile approach not only to explore potential data heteroscedasticity but also to generate confidence bands for the purpose of price stability *** then evaluate our models by comparing the prediction intervals generated from the quantile regression models with in-sample and out-of-sample *** monthly data from January 2000 to October 2010,we observed these findings：（i） the price changes of cost factors asymmetrically and unequally influence those of the livestock across different quantiles;（ii） the performance of our models is robust and consistent for both in-sample and out-of-sample forecasts;（iii） the confidence intervals generated from 0.05th and 0.95th quantile regression models are good methods to forecast livestock price fluctuation.

关键词： cost factors agricultural products forecasting price movements quantile regression model