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Triaxial ellipsoid models of the Moon based on the laser altimetry data of Chang'E-1

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Science china Earth sciences 2010年第11期53卷 1594-1601页

作者： WANG WenRui1,2,3, LI Fei1, LIU JianJun1, REN Xin2, ZOU XiaoDuan2,3, MU LingLi2, YAN JianGuo1, ZOU YongLiao2, ZHANG HongBo2, Lü Chang2, LIU JianZhong2, ZUO Wei2, SU Yan2, WEN WeiBin2, BIAN Wei2, WANG Min2, LI ChunLai2 & OUYANG ZiYuan2 1 school of Geodesy and Geomatics, Wuhan University, Wuhan 430079, china 2 National Astronomical Observatory of chinese academy of sciences, Beijing 100012, china 3 graduate school of chinese academy of sciences, Beijing 100049, china 1. school of Geodesy and Geomatics Wuhan University Wuhan 430079 China2. National Astronomical Observatory of Chinese Academy of Sciences Beijing 100012 China3. Graduate School of Chinese Academy of Sciences Beijing 100049 China

Lunar geodetic parameters, which play an important role in lunar exploration, can be calculated from the gravity and topography data. With the CE-1 altimetry data and LP gravity model, we calculate such geodetic parameters as the principle moment of inertia, the principle inertia axes, equatorial radius, polar radius, mean radius, flattening and offset between center of mass and center of figure (DCOM-COF). According to the CE-1 altimetry data and the above geodetic parameters, a tri-axial ellipsoid (CE-1-LAM-GEO) and a tri-axial level ellipsoid (CE-1-LAM-LEVEL) are calculated individually, providing mass center and figure center offset (DCOM-COF) and parameters more reliable in direction and magnitude.

关键词： Chang’E-1 laser altimetry data lunar ellipsoid lunar gravity

The contribution of cis-regulatory elements to head-to-head gene pairs' co-expression pattern

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Science china(Life sciences) 2009年第1期52卷 74-79页

作者： HAO Pei1,2,YU Yao2,3,ZHANG XiaoYan4,TU Kang2,FAN HaiWei2 & ZHONG Yang1 1 school of Life sciences,Fudan University,shanghai 200433,china 2 Bioinformatics Center,Key Lab of Systems Biology,shanghai Institutes for Biological sciences,chinese academy of sciences,shanghai 200031,china 3 shanghai Center for Bioinformation Technology,shanghai 200235,china 4 school of Life sciences,Tongji University,shanghai 200092,china 1. school of Life sciences Fudan University Shanghai 200433 China 2. Bioinformatics Center Key Lab of Systems Biology Shanghai Institutes for Biological Sciences Chinese Academy of Sciences Shanghai 200031 China 3. shanghai Center for Bioinformation Technology Shanghai 200235 China 4. school of Life sciences Tongji University Shanghai 200092 China

Transcription regulation is one of the most critical pipelines in biological process,in which cis-elements play the role as gene expression *** attempt to deduce the principles underlying the co-expression of "head-to-head" gene pairs by analyzing activities or behaviors of the shared cis-elements.A network component analysis was performed to estimate the impact of cis-elements on gene promoters and their activities under different *** discoveries reveal how biological system uses those regulatory elements to control the expression pattern of "head-to-head" gene pairs and the whole transcription regulation system.

关键词： transcription regulation cis-elements "head-to-head" gene pairs

Early scale effect and hemisphere superiority on the visual spatial attention:From the electrophysiological evidence of ERP

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Progress in Natural Science:Materials International 2004年第10期14卷 35-39页

作者： SONG Weiqun 1,3 ,GAO Yuan 1 and LUO Yuejia 1,2 (1.Key Laboratory of Mental Health,Institute of Psychology,chinese academy of sciences,Beijing100101,china 2.school of Psy-chology,Southwest china Normal University,Chongqing400715,china 3.graduate school of the chinese academy of sciences,Bei-jing100039,china) chinese Acad Sci Inst Psychol Key Lab Mental Hlth Beijing 100101 Peoples R China SW china Normal Univ Sch Psychol Chongqing 400715 Peoples R China chinese Acad Sci Grad Sch Beijing 100039 Peoples R China

The visual attention mechanism in the brain was studied among16young subjects through the precue-target visual search paradigm using the event-related potentials(ERPs)technique,with the attentive ranges cued with different scales of chinese *** results showed that the response time was shortened as the cue scale was reduced,while the amplitudes of the P1and N1components of the ERPs *** results not only provided the electrophysiological evidence supporting the spotlight theory,but also indicated that the spotlight effect occurred during the early period of the selected *** kinds of separation in the P2effect were *** separation was between the P1effect and P2effect,which meant that additional computation was needed when the spatial scale of attention was enlarged;the other was between the left and right hemisphere of the P2effect,which indicates that the at-tentive processing of the cue range mainly occurred in the left hemisphere.

关键词： visual spatial attention cue scale spotlight effect hemisphere superiority event-related potential(ERP)

Φ Meson Production in Heavy Ion Collisions at RHIC

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原子核物理评论 2009年第S1期26卷 142-147页

作者： SHI Xing-hua1,2,CHEN Jin-hui1,MA Yu-gang1,CAI Xiang-zhou1,MA Guo-liang1 (1 shanghai Institute of Applied Physics, chinese academy of sciences, shanghai 201800, china 2 graduate school of chinese academy of sciences, Bejing 100049, china) shanghai Institute of Applied Physics Chinese Academy of SciencesShanghai 201800China graduate school of chinese academy of sciences Bejing 100049China shanghai Institute of Applied Physics Chinese Academy of SciencesShanghai 201800China

We present Φ meson production in Cu+Cu and Au+Au collisions measured by the STAR experiment at *** hadronic decay mode Φ→ K+K-is used in the *** yields for Φ meson in Cu+Cu and Au+Au collisions at a given beam energy are scaled by the number of *** Npart normalized Φ meson yields in heavy ion collisions over those from p+p collisions are larger than 1 and increase with collision *** results suggest that the source of enhancement of strange hadrons is related to the formation of a dense medium in high energy heavy ion collisions and can not be only due to canonical suppression of their production in smaller *** also present STAR results on the Φ meson elliptic flow v2 from sNN=200 GeV Cu+Cu at *** elliptic flow in Cu+Cu system that has the similar relative magnitude and qualitative features as that in Au+Au *** observations imply the hot and dense matter with partonic collectivity has been formed in heavy ion collisions at RHIC. However,eccentrality normalized v2,v2/(nqεpart) is lower for Cu+Cu than for Au+Au collisions at 200 *** this might indicate thermalization has not been reached in 200 GeV Cu+Cu collisions.

关键词： Φ meson production elliptic flow

Orbit determination for geostationary satellites with the combination of transfer ranging and pseudorange data

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Science china(Physics,Mechanics & Astronomy) 2010年第9期53卷 1746-1754页

作者： GUO Rui1,2,3,4,HU XiaoGong2,4,LIU Li1,WU XiaoLi1,HUANG Yong2,4 & HE Feng1 1 Beijing Global Information Application and Development Center,Beijing 100094,china 2 shanghai Astronomical Observatory,chinese academy of sciences,shanghai 200030,china 3 graduate University of chinese academy of sciences,Beijing 100049,china 4 Space Navigation and Positioning Technology,Laboratory of shanghai Municipal,shanghai 200030,china 1. Beijing Global Information Application and Development Center Beijing 100094 China2. Shanghai Astronomical Observatory Chinese Academy of Sciences Shanghai 200030 China3. Graduate University of Chinese Academy of Sciences Beijing 100049 China4. Space Navigation and Positioning Technology Laboratory of Shanghai Municipal Shanghai 200030 China

Geostationary satellites(GEOs) play a significant role in the regional satellite navigation *** experiments show that the clock corrections could be mitigated through a single strategy or double differencing strategies for a navigation constellation,but for the mode of individual GEO orbit determination,high precision orbit and clock correction could not be obtained in the orbit determination based on the pseudorange data.A new GEO combined precise orbit determination(POD) strategy is studied in this paper,which combines pseudorange data and C-band transfer ranging *** strategy overcomes the deficiency of C-band transfer ranging caused by limited stations and tracking time *** the combination of transfer ranging and pseudorange data,clock corrections between the GEO and the stations can be estimated simultaneously along with orbital parameters,maintaining self-consistency between the satellite ephemeris and clock correction *** error covariance analysis is conducted to illuminate the contributions from the transfer ranging data and the psudoranging *** data collected for a chinese GEO satellite with 3 C-band transfer ranging stations and 4 L-band pseudorange tracking stations,POD experiments indicate that a meter-level accuracy is *** root-mean-square(RMS) of the post-fit C-band ranging data is about 0.203 m,and the RMS of the post-fit pseudorange is 0.408 *** component errors of the POD experiments are independently evaluated with the satellite laser ranging(SLR) data from a station in Beijing,with the residual RMS of 0.076 *** SLR evaluation also suggests that for 2-h orbital predication,the predicted radial error is about 0.404 m,and the clock correction error is about 1.38 *** for the combination of one C-band transfer ranging station and 4 pseudorange stations,POD is able to achieve a reasonable accuracy with the radial error of 0.280 m and the 2-h predicted radial error of 0.888 *** syn

关键词： satellite navigation precise orbit determination pseudorange equipment ranging delay GEO SLR

Phase diagram calculation method of thermodynamics-atomic parameters-artificial neural network

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chinese Science Bulletin 1999年第9期44卷 860-861页

作者： ZENG Wenming , ZHANG Lin and CHEN Nianyi State Key Laboratory of High Performance Ceramics and Superfine Microstructure Studies , shanghai Institute of Ceramics , chinese academy of sciences , shanghai 200050, china shanghai Hongqiao Middle school, shanghai 200335 , china shanghai Institute of Metallurgy , chinese academy of sciences , shanghai 200050, china State Key Laboratory of High Performance Ceramics and Superfine Microstructure Studies Shanghai Institute of Ceramics Chinese Academy of Sciencu Shanghai China shanghai Hongqiao Middle school Shanghai China shanghai Incritute of Merallurgy Chinese Academy of Sciences Shanghai China

A LTHOUGH the computerized prediction of phase diagrams by thermodynamic method has made great achievements, the lack of thermodynamic, data is one of the obstacles for unknown phase diagram prediction. Miedema has proposed to use atomic parameters for thermodynamic property estimation of alloy systems. Chen and co-workersL have used artificial neural network and atomic parameters to predict some thermodynamic properties, such as melting point, melting types. In this work, we presented a new method for phase diagram calculation by combining thermodynamics with atomic parameters and artificial neural network. In this method, the interaction parameters of the solutions were first computed from phase diagram of the binary systems. Then artificial neural network and atomic parameters were used to

关键词： thermodynamics obstacles computerized melting eutectic temper leaving Gibbs excess radius

A simple solution route to control synthesis of Fe_3O_4 nanomaterials at low temperature and their magnetic properties

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Science china Chemistry 2009年第7期52卷 916-923页

作者： LIU Yi1,2, CHEN Yun1, ZENG YuPing2 & WANG ShiLong3 1 Department of Chemistry and Chemical Engineering, Zaozhuang University, Zaozhuang 277160, china 2 shanghai Institute of Ceramics, chinese academy of sciences, shanghai 200050, china 3 school of Life Science and Technology, Tongji University, shanghai 200092, china 1. Department of Chemistry and Chemical Engineering Zaozhuang University Zaozhuang 277160 China 2. shanghai Institute of Ceramics Chinese Academy of Sciences Shanghai 200050 China 3. school of Life Science and Technology Tongji University Shanghai 200092 China

A series of nanostructured iron compounds including cubic Fe3O4 and orthorhombic FeOOH were synthesized via a facile low temperature (in the range of 60-100℃) solution method. In the whole process, the interaction between FeCl2·4H2O and methenamine (C6H12N4) was carried out through a reflux device under different reaction conditions such as temperature, solvent, and duration. The samples were detected by XRD, TEM, SAED, physical property measurement system, and Mssbauer spectroscopy, separately. The experiments showed that magnetic mixture nanoparticles had flake and rod morphologies, and cubic Fe3O4 took on grain nanostructure. Magnetism measurements indicated that the saturated magnetization of the as-obtained magnetic mixture was lower than that of the cubic magnetite. Mssbauer spectroscopy testified the sample consisting of cubic magnetite rather than γ-Fe2O3. In addition, a possible growth mechanism of cubic magnetic nanoparticles under different conditions was discussed.

关键词： magnetic nanoparticles cubic Fe3O4 oxidation-coprecipitation method reflux magnetic properties at room temperature Mssbauer spectrum

Adaptive quasi-likelihood estimate in generalized linear models

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Science china Mathematics 2005年第6期48卷 829-846页

作者： CHEN Xia & CHEN Xiru school of Mathematics and Statistics, Wuhan University, Wuhan 430072, china graduate school, chinese academy of Science, Beijing 100049, china 1. school of Mathematics and Statistics Wuhan University 430072 Wuhan China 2. graduate school Chinese Academy of Science 100049 Beijing China

This paper gives a thorough theoretical treatment on the adaptive quasilikelihood estimate of the parameters in the generalized linear models. The unknown covariance matrix of the response variable is estimated by the sample. It is shown that the adaptive estimator defined in this paper is asymptotically most efficient in the sense that it is asymptotic normal, and the covariance matrix of the limit distribution coincides with the one for the quasi-likelihood estimator for the case that the covariance matrix of the response variable is completely known.

关键词： generalized linear models, quasi likelihood estimate, adaptive estimate.

The Urbanization Pattern of china in the 21st Century

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中国人口·资源与环境：英文版 2005年第2期3卷 55-63页

作者： Wang Chengxin 1,2, Yao Shimou 1 & Wang Gefang 31 Nanjing Institute of Geography & Limnology, the chinese academy of sciences, Nanjing 210008, china 2 graduate school, the chinese academy of Science, Beijing 100039, china 3 Shandong Party school of the Communist Party, Jinan 250021, china Nanjing Institute of Geography and Limnology Chinese Academy of Sciences Nanjing 210008 China graduate school Chinese Academy of Science Beijing 100039 China Shandong Party school of the Communist Party Jinan 250021 China

The 21st century is referred to as a"century for cities" or "era for cities" and china hasalso speeded up its process of urbanization. It is veryimportant to choose a scientific urbanization patternto exert the function of cities and realize our dreamfor china to become a powerful modernized ***’s concluded from history since 1800 that the patternof the world urbanization has transformed from"extensive" to "intensive". However, it is still anextensive pattern in china, and there are manyproblems behind the splendid achievements, reflectedon the urbanization process of our country since1949. Today, sustainable development and theknowledge economy are the themes of the cities; itis inevitable to change our urbanization *** on the dialectic relationship of quality andquantity, the article points out that urbanizationshould not only focus on quantity but also on qualityin china. High quality and multiform urbanizationpattern is an inevitable choice of china, and thedevelopment of the region can also be exalted by theradiation of the cities. But what’s the real meaningof the new pattern? What’s its difference from thewestern countries’? The article discusses its contentaccording to the reality of china.

关键词： Urbanization pattern multiform intensive china