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Journal of Computational Mathematics 2002年第1期20卷 35-56页

作者： Lan Chieh Huang (ICMSEC, academy of Mathematics and System sciences, chinese academy of sciences, beijing 100080, china) ICMSEC Academy of Mathematics and System Sciences Chinese Academy of Sciences 北京 100080

Focuses on a study on the fully implicit Crank Nicholson (CN) schemes and three projection methods for approximate preservation of component-consistency under projection. Transformation from incompressible Navier-Stokes equations to differential algebraic equations CN schemes; Local errors of CN projection methods; Numerical boundary conditions.

关键词： differential algebraic equations discrete projection numerical boundary conditions

SUSPENDED SEDIMENT TRANSPORT IN THE OFFSHORE NEAR YANGTZE ESTUARY

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Journal of Hydrodynamics 2008年第3期20卷 373-381页

作者： CHEN Bin WANG Kai Institute of Oceanology Chinese Academy of Sciences Qingdao 266071 China Graduate University of the chinese academy of sciences Beijing 100039 China

Based on the Estuarine, Coastal and Ocean Modeling System with Sediments （ECOMSED） model, a 3-D hydrodynamic-transport numerical model was established for the offshore area near the Yangtze Estuary in the East china Sea .The hydrodynamic module was driven by tide and wind. Sediment module included sediment resuspension, transport and deposition of cohesive and non-cohesive sediment. The settling of cohesive sediment in the water column was modeled as a fimction of aggregation （flocculation） and deposition. The numerical results were compared with observation data for August, 2006. It shows that the sediment concentration reduces gradually from the seashore to the offshore area. Numerical results of concentration time series in the observation stations show two peaks and two valleys, according with the observation data. It is mainly affected by tidal current. The suspended sediment concentration is related to the tidal current during a tidal cycle, and the maximum concentration appears 1 h-4 h after the current maximum velocity has reached.

关键词： Yangtze Estuary sediment concentration sediment transport

Identification of the Angel -related elements in cyprinid fishes and their phylogenetic implications

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Progress in Natural Science:Materials International 2007年第2期17卷 168-171页

作者： WANG Li, HE Shunping and CHEN Yiyu ( Institute of Hydrobiology, chinese academy of sciences, Wuhan 430072, china Graduate School of the chinese academy of sciences, beijing 100039, china National Natural Science Foundation of china, beijing 100085, china) [a]chinese academy of sciences Institute of Hydrobiology Wuhan China [b]Graduate School of the chinese academy of sciences Beijing China [c]National Natural Science Foundation of china Beijing China

Angel-related element belongs to the family of miniature inverted-repeat transposable elements (MITEs). In this paper we report the identification of an Angel- related element in the series Leuciscini of cyprinid fishes, which is located in the second intron of the growth hormone (GH) gene. We have also found that this element is absent in orthologous locus in the series Barbini of cyprinid fishes, that provides new evidence for the monophyly of the series Leuciscini. The insertion of Angel -related element into the GH gene might take place in the common ancestor of the series Leuciscini after its divergence from the series Barbini. The high sequence divergence and relatively broad species distribution of Angel-related elements implies that they might be ancient transposons which appeared about 26 million years ago.

关键词： Angel -related elements the series Leuciscini monophyly.

MODELLING AND NUMERICAL SOLUTIONS OF A GAUGE PERIODIC TIME DEPENDENT GINZBURG-LANDAU MODEL FOR TYPE-Ⅱ SUPERCONDUCTORS

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Journal of Computational Mathematics 1997年第4期15卷 365-384页

作者： Zhi-ming Chen (Institute of Mathematics, chinese academy of sciences, beijing, china) 中科院数学所北京

In this paper we seek the solutions of the time dependent Ginzburg-Landau model for type-Ⅱ superconductors such that the associated physical observables are spatially periodic with respect to some lattice whose basic lattice cell is not necessarily rectangular. After appropriately foring the gange, the model can be formulated as a system of nonlinear parabolic partial differential equations with quasi-periodic boundary conditions. We first give some results concerning the existence, uniqueness and regularity of solutions and then we propose a semiimplicit finite element scheme solving the system of nonlinear partial dmerential equations and show the optimal error estimates both in the L2 and energy *** also report on some numerical results at the end of the paper.

关键词： Math QT MODELLING AND NUMERICAL SOLUTIONS OF A GAUGE PERIODIC TIME DEPENDENT GINZBURG-LANDAU MODEL FOR TYPE SUPERCONDUCTORS

2.2. Guideline for the management of hypertension in the elderly population in china

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Journal of Geriatric Cardiology 2024年第6期21卷 589-630页

作者： Hypertension Branch of chinese Geriatrics Society,beijing Hypertension Association,National Clinical Research Center of the Geriatric Diseases Qi HUA Li FAN Zeng-Wu WANG Jing LI 不详 Xuanwu Hospital Capital Medical UniversityBeijingChina chinese PLA General Hospital BeijingChina Fuwai Hospital Chinese Academy of Medical Sciences and Peking Union Medical CollegeBeijingChina

Preamble Hypertension is one of the most common chronic diseases and the primary risk factor for stroke,myocardial infarction and even cardiovascular *** than half of the elderly population has high blood *** people are a unique group,and strategies for the prevention,diagnosis,evaluation,and treatment of hypertension in elderly individuals differ significantly from those in the general population.

关键词： hypertension prevention diagnosis

A novel operation mode for spaceborne polarimetric SAR

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Science china(Information sciences) 2011年第4期54卷 884-897页

作者： QI WeiKong 1,2 & YU WeiDong 1 1 Institute of Electronics,chinese academy of sciences,beijing 100190,china 2 Graduate School of chinese academy of sciences,beijing 100039,china 1. Institute of Electronics Chinese Academy of Sciences Beijing 100190 China2. Graduate School of Chinese Academy of Sciences Beijing 100039 China

A novel operation mode for spaceborne polarimetric SAR,named polarization space-division adding polarization code-division (PSD-PCD) operation mode,is proposed in this paper through combining polarimetric SAR with elevation digital beam-forming (DBF) on *** a pulse repetition interval the up-chirp LFM sub-pulse is transmitted with horizontal polarization antenna,and with some delay the down-chip LFM subpulse is transmitted with vertical polarization antenna to realize code *** every sub-aperture receives returns from ground,SAR system uses range DBF to separate echoes relative to different sub-pulses in order to realize space *** system PRF is equal to that of single-polarization SAR,and elevation DBF help reduce range ambiguity ***,the main system parameters,including PRF,delay between two sub-pulses,radar equation and ambiguity are analyzed and compared with those of single-polarization *** results demonstrate the feasibility and validity of PSD-PCD operation mode.

关键词： spaceborne synthetic aperture radar (SAR) polarimetry digital beamforming (DBF) operation mode ambiguity ratio polarization space-division polarization code-division

Genetic fingerprinting of plankton community provides new insights into aquatic ecology

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Progress in Natural Science:Materials International 2006年第9期16卷 893-898页

作者： YAN Qingyun, YU Yuhe and FENG Weisong ( Institute of Hydrobiology, chinese academy of sciences, Wuhan 430072, china Graduate School of the chinese academy of Sci-ences, beijing 100039, china) [a]Institute of Hydrobiology Chinese Academy of Sciences Wuhan China [b]Graduate School of the chinese academy of sciences Bejing China

Over the past two decades, molecular techniques have been widely used in ecological study and molecular ecology has been one of the most important branches of ecology. Meanwhile, genetic fingerprinting analyses have significantly enhanced our knowledge of the diversity and evolutionary relations of the planktonic organisms. Compared with conventional approaches in ecological study (e.g. morphological classification), genetic fingerprinting techniques are simpler and much more effective. This review provides an overview of the principles, advantages and limitations of the commonly used DNA fingerprinting techniques in plankton research. The aim of this overview is to assess where we have been, where we are now and what the future holds for solving aquatic ecological problems with molecular-level information.

关键词： genetic fingerprinting plankton community aquatic ecology genetic diversity.

Models and methods for precise determination of ionospheric delay using GPS

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Progress in Natural Science:Materials International 2007年第2期17卷 187-196页

作者： YUAN Yunbin, HUO Xingliang and OU Jikun ( Institute of Geodesy and Geophysics, chinese academy of sciences, Wuhan 430077, china Graduate University of chinese A-cademy of sciences, beijing 100039, china) [a]chinese academy of sciences Institute of Geodesy and Geophysics Wuhan China [b]Graduate University of chinese academy of sciences Beijing China

The basic principles and methods for precisely determining ionospheric delays in GPS observations are introduced and discussed. Various methods and models for fitting ionospheric delays based on GPS are compared and a... 详细信息

关键词： GPS ionospheric delay atmosphere modeling precise GPS positioning.

Experimental study on phosphorus release from sediments of shallow lake in wave flume

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Science china Earth sciences 2006年第z1期49卷 92-101页

作者： SUN Xiaojing,ZHU Guangwei, LUO Liancong & QIN Boqiang Nanjing Institute of Geography & Limnology, chinese academy of sciences, Nanjing 210008, china Graduate School of chinese academy of sciences, beijing 100039, china 1. Nanjing Institute of Geography & Limnology Chinese Academy of Sciences Nanjing 210008 China2. Graduate School of Chinese Academy of Sciences Beijing 100039 China

Influence of wave on sediment resuspension and nutrients release from sediments, collected from Lake Taihu and Lake Chaohu, was studied in flume experiments. Under strong-wave conditions, concentrations of suspended solids (SS), total phosphorus (TP) and dissolved total phosphorus (DTP) in overlying water were increased significantly following the sediments re-suspension. During the experiments on sediments of Lake Taihu and Lake Chaohu, TP concentrations increased 6 times and 3 times, and DTP concentration increased 100% and 70% more than it in presuspension, respectively. Concentration of soluble reactive phosphorus (SRP) of experiment on sediment of Lake Taihu increased 25%. During the massive sediment suspension, the dissolved phosphorus in pore water and much of the phosphorus adsorbed by the sediment particles were released into overlying water. The phenomena in this wave flume experiment are quite similar to the situation observed in situ of Lake Taihu. The critical wave stresses of sediment re-suspension are nearly equal. The change of concentrations of SS, TP, and SRP was the same as that in situ *** study showed that concentrations of TP and SRP in lake water could be increased significantly by wave disturbance. Phosphorus release was significantly enhanced by wave disturbance at the beginning of massive sediment re-suspension, but decreased later.

关键词： shallow lakes, wave disturbance, internal release, phosphorus, wave flume experiment.

The boundary of palaearctic and oriental realms in western china

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Progress in Natural Science:Materials International 2008年第7期18卷 833-841页

作者： Ling Chen a,b,c, Yanling Songd,*, Shufang Xu e a Northwest Institute of Plateau Biology, chinese academy of sciences, Xining 810001, china b Graduate University of the chinese academy of sciences, beijing 100039, china c National Science Foundation of china, beijing 100085, china d Institute of Zoology, chinese academy of sciences, beijing 100101, china e beijing academy of Agriculture and Forestry sciences, beijing 100097, china Northwest Institute of Plateau Biology Chinese Academy of Sciences Xining 810001 China Graduate University of the chinese academy of sciences Beijing 100039 China National Science Foundation of china Beijing 100085 China Institute of Zoology Chinese Academy of Sciences Beijing 100101 China beijing academy of Agriculture and Forestry sciences Beijing 100097 China

In the world-wide zoogeographic division, there has been no consentaneous understanding about the delimitation between palaearctic and oriental realms in western china. In this study, we will discuss the division based on amphibian distribution in Shaanxi, Gansu, Sichuan, Yunnan, and Tibet according to species coefficient similarity between each zoogeographic province. The results show that the northern border lies from Qinling Mountains–Feng Xian (Shaanxi)–Debu (Gansu)–Aba (Sichuan)–Batang–Bomi (Tibet), to Linzhi districts, and the southern border is from Taibai–Feng Xian in Shaanxi–Wen Xian (Gansu)–Songpan–Kangding–Daocheng (Sichuan), to Zhongdian–Gongshan in Yunnan, and westward to Motuo and Bomi district in Tibet.

关键词： Amphibian Zoogeography Palaearctic Oriental Hengduan Mt.