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The solid lubricating material experiment device for Shenzhou-7 Spaceship

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Science china(Technological sciences) 2010年第9期53卷 2521-2527页

作者： WANG Ke1,2,REN WeiJia1,WANG ShiDa1 & WENG LiJun3.1 academy of Opto-Electronics,chinese academy of {3.,beijing 100190,china 2 graduate University of chinese academy of {3.,beijing 100049,china 3.Lanzhou Institute of Chemical Physics,chinese academy of {3.,Lanzhou 73.000,china 1. academy of Opto-Electronics Chinese Academy of Sciences Beijing 100190 China2. Graduate University of Chinese Academy of Sciences Beijing 100049 China3. Lanzhou Institute of Chemical Physics Chinese Academy of Sciences Lanzhou 730000 China

A solid lubricating material exposure experiment in space is one of the missions during the seventh manned spaceflight of china,and the key is to develop a device which can be fixed reliably outside of the orbital module and can be fetched conveniently by an astronaut during space *** solid lubricating material experiment device needs to be locked reliably in a vibrating and impacting environment during the launch phase,and should meet the requirement that it can be unlocked and fetched reliably by the astronaut wearing an extravehicular spacesuit via simple operations in orbit in an environment of high and low *** for the device we developed,the environmental characteristic of the mission was analyzed,the mechanical analysis and thermal analysis were carried out,and then a mechanism with functions of mechanical locking,structural self-locking and manual unlocking was *** device was verified by a sequence of experiments and was fetched by the astronaut during the flight of the Shenzhou-7 Spaceship.

关键词： manned spaceflight exposure experiment mechanism unlock

Prediction method for October 2003.solar storm

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Science china(Technological sciences) 2006年第5期49卷 629-640页

作者： XIE Yanqiong1, 2, 3. WEI Fengsi1, FENG Xueshang1 & ZHONG Dingkun1, 2 1. State Key Laboratory of Space Weather, Center for Space Science and Applied Research, chinese academy of sciences, {3. 100080, china 2. graduate school, chinese academy of sciences, beijing 100039, china 3. Institute of Meteorology, PLA University of Science and Technology, Nanjing 211101, china State Key Laboratory of Space Weather Center for Space Science Applied Research Chinese Academy of Sciences Beijing 100080 China graduate school Chinese Academy of Sciences Beijing 100039 China Institute of Meteorology PLA University of Science Technology Nanjing 211101 China

Aiming at two intense shock events on October 28 and 29, 2003. this paper presents a two-step method, which combines synoptic analysis of space weather ——“observing” and quantitative prediction ——“palpating”, and then uses it to test predictions. In the first step of “observing”, on the basis of observations of the solar source surface magnetic field, interplanetary scintillation (IPS) and ACE spacecraft, we find that the propagation of the shocks is asymmetric relative to the normal direction of their solar sources, and the Earth is located near the direction of the fastest speed and the greatest energy of the shocks. As the two fast ejection shock events, the fast explosion of coronal mass of the extremely high temperature, the strong magnetic field, and the high speed background solar wind are also helpful to their rapid propagation. In the second step of “palpating”, we adopt a new membership function of the fast shock events for the ISF method. The predicted results show that for the onset time of the geomagnetic disturbance, the relative errors between the observational and the predicted results are 1.8% and 6.7%; and for the magnetic disturbance magnitude, the relative errors are 4.1% and 3.1%, re- spectively. Furthermore, the comparison among the predicted results of our two-step method with those of five other prevailing methods shows that the two-step method is advantageous. The results tell us that understanding the physical features of shock propagation thoroughly is of great importance in improving the prediction precision.

关键词： solar storm, interplanetary shock, interplanetary scintillation, two-step method, ISF method.

A subsurface runoff parameterization with water storage and recharge based on the Boussinesq-Storage Equation for a Land Surface Model

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Science china Earth sciences 2006年第6期49卷 622-631页

作者： TIAN Xiangjun1,2, XIE Zhenghui1, ZHANG Shenglei1 & LIANG Miaoling1 1. LASG, Institute of Atmospheric Physics, chinese academy of sciences, {3. 100029, china 2. graduate school of the chinese academy of sciences, beijing 100039, china 1. LASG Institute of Atmospheric Physics Chinese Academy of Sciences Beijing 100029 China 2. graduate school of the chinese {3. of sciences Beijing 100039 China

Subsurface runoff in a land surface model is usually parameterized as a single-valued function of total storage in a basin aquifer reservoir. This kind of parameterization is often sin-gle-valued function of storage-discharge under a steady or “quasi-steady” state, which cannot rep-resent the influence of aquifer recharge on subsurface runoff generation. In this paper, a new sub-surface runoff parameterization with water storage and recharge based on the Boussinesq-storage equation is developed. This model is validated by a subsurface flow separation algorithm for an ex-ample river basin, which shows that the new model can simulate the subsurface flow reasonably.

关键词： Zsubsurface runoff parameterization Boussinesq-storage equation waterstorage and recharge

STUDY OF IMPACT OF ESTABLISHMENT OF A DAM ON LOCAL TIDAL CURRENTS IN KENDONG OIL FIELD

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Journal of Hydrodynamics 2004年第3期16卷 356-365页

作者： LIUHao YINBao-shu YUKe-jun YANGDe-zhou XUYan-qing InstituteofOceanology ChineseAcademyofSciencesQingdao266071China InstituteofOceanology.chineseacademyofsciences Qingdao266071China

In this paper a three-dimensional tidal current model has been used toexamine variations of local fluid field due to establishment of a dam. By imputing ten tides-K_1,O_1, P_1 , Q_1, M_2, S_2, N_2, K_2 , S_a and S_(sa) through the open boundary of the Bohai straitand adopting 5′ x 5′ horizontal resolution the whole fluid field of the Bohai Sea was firstsimulated. The computed harmonic constants of m_1 and M_2 tides at seventeen observational stationsalong the coast of the Bohai Sea matched the observed values rather well. Taking the calculatednumerical results as open boundary conditions, the local fluid field in the Kendong Oil Field bymeans of 1′ x 1′ horizontal resolution was then investigated. In the course of calculation, finegrids were embedded in coarse grids so as to enhance the computational order. In addition, thelatest water-depth data of the Huanghe Delta coast area were adopted, thus topographic changesbecause of silt sediment in that region wouldn''t affect the computed results. In the end, byanalyzing the relative changes of the fluid field before and after the dam was established, that theeffect on the dynamic environment of the local sea area mainly concentrated on the adjacentpositions north and south of the dam was suggested.

关键词： tidal current harmonic constants open boundary frequency analysis

Non-Gaussianity of Racetrack Inflation Models

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Communications in Theoretical Physics 2007年第7期48卷 189-192页

作者： SUN Cheng-Yit ZHANG De-Hai Department of Physics,The graduate school of The chinese {3. of sciences,beijing 100049,china Department of Physics The Graduate School of The Chinese Academy of Sciences Beijing 100049 China

In this paper,we use the result in[*** and ***,arXiv:astro-ph/0510709]to calculate thenon-Gaussianity of the racetrack models in[***-Pillado,et al.,JHEP 0411(2004)063.arXiv:hep-th/040623.]and[***-Pillado,et al.,arXiv:hep-th/0603.29].The two models give different *** of themare ***,we find that,for multi-field inflationary models with the non-trivial metric of the field space,the condition of the slow-roll cannot guarantee small non-Gaussianities.

关键词： non-Gaussianity non-linear parameter racetrack inflation

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 sciences, {3. 100080, china 2 graduate school, chinese academy of sciences, beijing 100039, 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

An Efficient High-Resolution Shock-Capturing Scheme for Multi-Dimensional Flows I. Hydrodynamics

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chinese Journal of Astronomy and Astrophysics 2006年第6期6卷 680-688页

作者： Cong Yu National Astronomical Observatories / Yunnan Astronomical Observatory, chinese academy of sciences, Kunming 650011 {3. school of chinese academy of sciences, beijing 100049 graduate school of chinese {3. of sciences Beijing 100049

Many problems at the forefront of theoretical astrophysics require a treatment of dynamical fluid behavior. We present an efficient high-resolution shock-capturing hydrodynamic scheme designed to study such phenomena. We have implemented a weighted, essentially non-oscillatory （WENO） scheme to fifth order accuracy in space, lILLE approximate Riemann solver is used for the flux computation at cell interface, which does not require spectral decomposition into characteristic waves and so is computationally friendly. For time integration we apply a third order total variation diminishing （TVD） Runge-Kutta scheme. Extensive testing and comparison with schemes that *** characteristic decomposition are carried out demonstrating the ability of our scheme to address challenging open questions in astrophysics.

关键词： accretion - hydrodynamics- method numerical - shock waves

Estimation of forest volumes by integrating Landsat TM imagery and forest inventory data

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Science china(Technological sciences) 2006年第z1期49卷 54-62页

作者： GU Huiyan, DAI Limin, WU Gang, XU Dong, WANG Shunzhong &WANG Hui Institute of Applied Ecology, chinese academy of sciences, Shenyang 110016,{3. school of Forestry, Northeast Forestry University, Harbin 150040,{3. State Key Lab of Systems Ecology, Research Center for Eco-Environmental sciences, chinese academy of sciences, beijing 100085,{3. graduate University of chinese academy of sciences, beijing 100039,{3. 1. Institute of Applied Ecology Chinese Academy of Sciences Shenyang 110016 China 2. school of Forestry Northeast Forestry University Harbin 150040 China 3. State Key Lab of Systems Ecology Research Center for Eco-Environmental Sciences Chinese Academy of Sciences Beijing 100085 China 4. graduate University of chinese academy of {3. Beijing 100039 China

Accurate information about forest volumes is essential for forest management planning. The survey interval of the Forest Resource Inventory of china (FRIC) is too long to meet the demand for timely decision-making required for forest protection, management, and utilization. Analysis of satellite imagery provides good potential for more frequent reporting of forest parameters. In this study, we describe an application of the k-nearest neighbors (kNN) method to Landsat TM imagery for improving estimation of forest volumes. Several spectral features were tested and compared in forest volume estimations, including normalized difference vegetation index, environmental vegetation index, and the combination of the spectral features. The combined index resulted in the most accurate volume estimations. The kNN estimator and the combined index were then used in forest volume estimation. The estimation error (RMSE) of the total volume was44.2%, much lower than those for Larix forest (the RMSE was 51.7%) and those for the Korean pine and broadleaved forests (the estimation errors were over 71.7% and 88.19%,respectively). This preliminary study demonstrates the potential of forest volume estimations with remote sensing data to provide useful information for forest management if only limited ground information is available.

关键词： forest inventory, landsat TM, k-nearest neighbors, spectral extraction.

Modeling diameter distribution of the broadleaved-Korean pine mixed forest on Changbai Mountains of china

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Science china(Technological sciences) 2006年第z1期49卷 177-188页

作者： WANG Shunzhong, DAI Limin, LIU Guohua, YUAN Jianqiong, ZHANG Hengmin & WANG Qingli Institute of Applied Ecology, chinese academy of sciences, Shenyang 110016,{3. graduate University of chinese academy of sciences, beijing 100039,{3. State Key Lab of Systems Ecology, Research Center for Eco-Environmental sciences, chinese academy of sciences, beijing 100085,{3. Institute of Applied Ecology Chinese Academy of Sciences Shenyang 110016 China graduate University of chinese academy of {3. Beijing 100039 China State Key Lab of Systems Ecology Research Center for Eco-Environmental Sciences Chinese Academy of Sciences Beijing 100085 China

The broadleaved-Korean pine mixed forest is a native vegetation in the Changbai Mountains, northeast china. The probability density functions including the normal, negative exponential, Weibull and finite mixture distribution, were used to describe the diameter distributions of the species groups and entire forest stand. There is a strong correlation between parameters and mean DBH except the shape parameters in the mixture distribution. The diameter classes of species and entire forest stand showed not negative exponential but normal and "S" distribution. The mixture function was better than normal and Weibull to describe the model distribution. The location parameter had an effect on the estimated frequency in the first diameter class, when the estimated location parameter was bigger than the lower limit of the first diameter class.

关键词： broadleaved-Korean pine mixed forest, diameter distribution, finite mixture distribution.