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Persistent anomalous flows over the subtropical western Pacific insummer

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chinese Science Bulletin 1998年第8期43卷 672-675页

作者： ZHUANG Shiyu\+1.and JI Liren\+2.1. National {1. Centre, china {1. Administration, Beijing 1.0081. china 2. LASG, Institute of Atmospheric Physics, chinese academy of sciences, Beijing 1.0080, china National meteorological Ccntre China Meteomlcgical Administration Beijing China LASG Institute of Atmospheric Physics Chinese Academy of Sciences Beijing China

The distribution of global persistent anomalies shows that the subtropical western Pacific is a key region with high_frequency occurrence of persistent anomalies. Analyses of streamfunction anomalies, OLR anomalies etc. suggest that the convective heating related to Indian monsoon might be responsible for the development of WPA. The results of numerical experiment by two linear barotropic models support the observation.

关键词： persistent anomalies subtropical high Indian monsoon anomalous forcing.

Case studies on mesoscale structures of heavy rainfall system in the Yangtze River generated by Meiyu front

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Science china Earth {1. 2005年第8期48卷 1303-1311页

作者： LIU Liping1. RUAN Zheng1.& QIN Danyu2.1. {1. academy of {2. sciences, Beijing 1.0081. china 2. Nanjing Institute of Meteorology, Nanjing 2.0044, china 1. chinese {1. of {2. sciences 100081 Beijing China 2. Nanjing Institute of Meteorology 210044 Nanjing China

A heavy rainfall system was observed over the Yangtze River during Meiyu season by using dual-Doppler radar systems in the field experiment conducted by the project of National Fundamental Research Planning “Research on formation mechanism and the prediction theory of hazardous weather over china”. The three-dimensional mesoscale kinematic structure and process of a heavy rain on {1. and {1. July, {1.0{1.are investigated by using the radial velocity and dual-Doppler radar technique. The results show that a southwest-northeast oriented rain band with the length of about 1.00 km involves numbers of meso-β or meso-γ-scale convective cells with the size of {1.―50 km. The heavy rain band in the middle reaches of the Yangtze River ex-ists in a low-level wind shear. The interaction between southwest low-level jet on the southern side of wind shear and east wind on the northern side formed the updraft. The wind disturbance, wind shear and convergence generate the convective action. The new cell developed in right rear flank of rain band and moved to the southwest wind area, where the vapor is abundant. This kind of echo can last a long time and developed well. The strong convective echoes are often ac-companied by the meso-γ-scale vortex and convergence.

关键词： heavy rainfall in Meiyu front, mesoscale structure, dual-Doppler radar, middle reaches of the Yangtze River, low-level jet.

Parentage determination of an isolated Yangtze finless porpoise population Neophocaena phocaenoides asiaeorientalis in the Yangtze Tian-e-Zhou Baiji National Natural Reserve based on molecular data

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Progress in Natural Science:Materials International 2005年第2期15卷 54-61页

作者： XIA Junhong 1.2. ZHENG Jinsong 1.2. XU Limei 1.2.and WANG Ding1.(1. Institute of Hydrobiology, chinese academy of {2., Wuhan 430072. china 2. Graduate School of the chinese academy of {2., Beijing 1.0039, china) Institute of Hydrobiology Chinese Academy of Sciences Wuhan 430072 China. Graduate School of the chinese {1. of {2. Beijing 100039 China

Reproductive behaviors are poorly known for the Yangtze finless porpoise Neophocaena phocaenoides asiaeorientalis. In this study, the parentage of an isolated Yangtze finless porpoise population inhabiting the Yangtze Tian-e-Zhou Baiji National Natural Reserve is determined by analysis of microsatellite loci and mitochondrial DNA (mtDNA) control region sequences, and the porpoise's reproductive behaviors are studied. Overall 4 full parentage assignments and additional 3 single parentage assignments were determined for the population of 2. individuals. The analysis shows that their estimated reproductive cycle is shorter than that reported previously and there probably exists an overlapping between gestation and lactation period. The study also shows that the female does not show fidelity to a particular male for breeding and vice versa, the oldest males did not monopolize mating and the dominance rank could not be so strict for the porpoise society. Moreover, the porpoise's mating pattern and relatedness among candidate parents are discussed here. These results provide important information for making guidelines of management and conservation for this protected population.

关键词： Yangtze finless porpoise isolated population reproductive behavior parentage

Wind vector retrieval using dual polarization imagery of ASAR

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Progress in Natural Science:Materials International 2006年第11期16卷 1183-1187页

作者： SONG Guiting~ 1.2., HOU Yijun~1.* and QI Peng~1.1. Institute of Oceanology, {1. academy of {2., Qingdao 2.6071. china 2. Graduate School, {1. academy of {2., Beijing 1.0039, china) [a]Institute of Oceanology Chinese Academy of Science Qingdao China [b]Graduate School Chinese Academy of Sciences Beijing China

A new algorithm for retrieving wind vector using dual polarization imagery of advanced synthetic aperture radar (ASAR) is developed and tested. Based on the combination of co-polarization and cross-polarization, this new algorithm effectively eliminates the 1.0° ambiguity which occurs when using single imagery of the ASAR to retrieve wind vector. This algorithm also solves the problem that the retrieval results will break down on very small spatial scales. The results retrieved from dual polarization imagery of ASAR show that the wind speed and direction are in agreement with the data from Quikscat and buoy measurements. The root mean square errors of wind direction and speed between the retrieved results and data from Quikscat are 2.2.° and 0.53 m/s, respectively. Comparisons between the new method and the traditional method show that the new methods fit the buoy data and Quikscat data a little better than the traditional method in this image.

关键词： wind vector retrieval ASAR dual polarization.

Recent study of emission line star 3G71

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chinese Science Bulletin 1998年第6期43卷 470-473页

作者： HANG Hengrong 1.2.and XIA Jianping+1.1. Purple Mountain Observatory, {1. academy of {2., Nanjing 2.0008, china 2. Joint Laboratory for Optical Astronomy, {1. academy of {2., Nanjing 2.0008, china Purple Mountain Observatory Chinese Academy of Sciences Nanjing China Joint Laboratory for Optical Astronomy Chinese Academy of Sciences Nanjing China

New spectral observations of 3G71.are presented. The main features of optical spectra which exhibit a lot of forbidden lines and unusual strong H-Balmer emission lines are discussed. Our data, together with its large IRAS infrared color excess and other characteristics, show evidence that the star may be a Herbig Ae/Be star rather than the optical counterpart of Be/X-ray source of 1.2.1.+589.

关键词： Be/X-ray binary emission line IRAS identification Herbig Ae/Be star.

Explicit analytical solutions of the anisotropic Brinkman model for the natural convection in porous media(Ⅱ)

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Science china(Physics,Mechanics & Astronomy) 2005年第4期48卷 422-430页

作者： CAI Ruixian1. GOU Chenhua1. 2.& ZHANG Na1.1. Institute of Engineering Thermophysics, {1. academy of {2., Beijing 1.0080, china 2. Graduate School, {1. academy of {2., Beijing 1.0080, china 1. Institute of Engineering Thermophysics Chinese Academy of Sciences 100080 Beijing China 2. Graduate School Chinese Academy of Sciences 10080 Beijing China

Some algebraically explicit analytical solutions are derived for the anisotropic Brinkman model―an improved Darcy model―describing the natural convection in porous media. Besides their important theoretical meaning (for example, in analyzing the non-Darcy and anisotropic effects on the convection), such analytical solutions can be the benchmark solutions that can promote the development of computational heat and mass transfer. Some solutions considering the anisotropic effect of permeability have been given previously by the authors, and this paper gives solutions including the anisotropic effect of thermal conductivity and the effect of heat sources.

关键词： explicit analytical solution, porous medium, natural convection, Brinkman model, anisotropic.

Assessing the Carrying Capacity of Tourist Resorts: An Application of Tourists’ Spatial Behavior Simulator Based on GIS and Multi-Agent System

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Wuhan University Journal of Natural sciences 2005年第4期10卷 779-784页

作者： ZHANG Ren-jun 1.2.1. Institute of Mountain Hazards and Environment, {1. academy of {2., Chengdu 61.041. Sichuan, china 2. Graduated School of the {1. academy of {2., Beijing 1.0039, china chinese {1. of {2. Institute of Mountain Hazards and Environment Chengdu Sichuan China (GRID:grid.9227.e) (ISNI:***) Graduated School of the chinese {1. of {2. Beijing China (GRID:grid.9227.e) (ISNI:***)

Based on the study of visitors' individual spatial behaviors, a tourists'spatial behavior simulator (TSBS) to assess the carrying capacity of tourist resorts was developed,TSBS employs GIS (Geographic Information System) to manage the spatial data,and Multi-Agent systemto simulate the actions of individual visitors. By utilizing TSBS, visitors' travel patterns such aslocation, cost, and state can be analyzed and predicted. Based on this analysis and prediction, themodel of assessing the carrying capacity of resorts is built. Our results show that TSBS will be aneffective tool to accurately assess the carrying capacity of tourist resorts.

关键词： tourist resort carrying capacity TSBS GIS Multi-Agent simulator

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, {1. academy of {2., Beijing 1.0080, china 2. Graduate School, {1. academy of {2., Beijing 1.0080, 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.

Some key technics of drop tower experiment device of National Microgravity Laboratory (china) (NMLC)

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Science china(Technological {1.) 2005年第3期48卷 305-316页

作者： ZHANG Xiaoqian 1., YUAN Longgen 1., WU Wendong 1., TIAN Lanqiao 2.& YAO Kangzhuang 2.1. Institute of Engineering Thermophysics, chinese academy of {2., Beijing 1.0080, china 2. Institute of Mechanics, chinese academy of {2., Beijing 1.0080, china 1. Institute of Engineering Thermophysics Chinese Academy of Sciences 100080 Beijing China 2. Institute of Mechanics Chinese Academy of Sciences 100080 Beijing China

Drop tower is an important ground based facility for microgravity science experiment. The technical performances of the drop tower NMLC are advanced compared with similar facilities in the US, Germany and Japan. The main components such as drop capsule, deceleration devices, release mechanism present its advantages and creativities.

关键词： drop tower facility,drop capsule,deceleration devices,release mechanism.