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Prediction method for October 2.03.solar storm

science china(Technological {2.) 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 {2. Weather,{3., chinese academy of sciences, beijing 100080, china 2. Graduate School, chinese academy of sciences, beijing 10003., china 3. Institute of Meteorology, PLA University of science and Technology, Nanjing 2.1101, 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 2. and 2., 2.03. this paper presents a two-step method, which combines synoptic analysis of {3. 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 {3.craft, 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.

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A CLASS OF TWO-STEP TVD MACCORMACK TYPE NUMERICAL SCHEME FOR MHD EQUATIONS

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空间科学学报 2003年第6期23卷 401-412页

作者： FENG Xueshang wei fengsi ZHONG Dingkun({2. for {3. {3. and applied research, The chinese academy of sciences, beijing 100080) center for space {2. and {3. research The Chinese Academy of Sciences 北京 100080

In this paper, a new numerical scheme of Total Variation Diminishing (TVD) MacCormack type for MagnetoHydroDynamic (MHD) equations is proposed by taking into account of the characteristics such as convergence, stability, resolution. This new scheme is established by solving the MHD equations with a TVD modified MacCormack scheme for the purpose of developing a scheme of quick convergence as well as of TVD property. To show the validation, simplicity and practicability of the scheme for modelling MHD problems, a self-similar Cauchy problem with the discontinuous initial data consisting of constant states, and the collision of two fast MHD shocks, and two-dimensional Orszag and Tang's MHD vortex problem are discussed with the numerical results conforming to the existing results obtained by the Roe type TVD, the high-order Godunov scheme,and weighted Essentially Non-Oscillatory (WENO) scheme. The numerical tests show that this two-step TVD MacCormack numerical scheme for MHD system is of robust operation in the presence of very strong waves, thin shock fronts, thin contact and slip surface discontinuities.

关键词：磁液体力学方程两步TVD-MacCormack图解法收敛性稳定性数值模拟

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The variation in the magnetic fluctuation anisotropy across the front boundaries of magnetic clouds and its geomagnetic response

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chinese science Bulletin 2002年第10期47卷 863-867页

作者： LIU Rui & wei fengsiDepartment of Geophysics, Peking University, {2. 100871,{3. Lab for {3. Weather, center for space science and applied research, chinese academy of sciences, beijing 100080,{3. Department of Geophysics Peking University Beijing China Lab for space Weather Center for Space Science and Applied Research Chinese Academy of Sciences Beijing China

A statistical study of magnetic fluctuations near the front boundaries of magnetic clouds is approached with the method of Minimum Variance Analysis, based on the data of ImpS and Wind spacecraft. New discoveries are that (1) fluctuation anisotropy tends to increase across the front boundaries of magnetic clouds; (2. there is a good correlation between the fluctuation anisotropy and the geomagnetic activity indices; and (3. in some cases, although there is southward field component immediately after the front boundary, Kp index descends (or Dst index ascends) with a corresponding decrease of the fluctuation anisotropy; in other cases with no distinct southward field component, Kp index ascends (or Dst index descends) with a corresponding increase of the fluctuation anisotropy. Thus we suggest that the fluctuation anisotropy might be a useful indicator in diagnosing the magnetic activities of magnetic clouds.

关键词： front boundary of magnetic clouds geomagnetic activity fluctuation anisotropy.

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Primary scientific results of Chang'E-1 lunar mission

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science china Earth {2. 2010年第11期53卷 1565-1581页

作者： OUYANG ZiYuan1,2. LI ChunLai1, ZOU YongLiao1, ZHANG HongBo1, Lü Chang1, LIU JianZhong1, LIU JianJun1, ZUO wei1, SU Yan1, WEN weiBin1, BIAN wei1, ZHAO BaoChang3. WANG JianYu4, YANG JianFeng3. CHANG Jin5, WANG HuanYu6, ZHANG XiaoHui7, WANG ShiJin7, WANG Min1, REN Xin1, MU LingLi1, KONG DeQing1, WANG XiaoQian1, WANG Fang1, GENG Liang1, ZHANG ZhouBin1, ZHENG Lei1, ZHU XinYing1, ZHENG YongChun1, LI JunDuo1, ZOU XiaoDuan1, XU Chun1, SHI ShuoBiao1, GAO YiFei1 & GAO GuanNan1 1 National Astronomical Observatories, chinese academy of sciences, beijing 100012.{2. 2.Institute of Geochemistry, chinese academy of sciences, Guiyang 550002.{2. 3.Xi’an Institute of Optics and Precision Mechanics, chinese academy of sciences, Xi’an 710119,{2. 4 Shanghai Institute of Technical Physics, chinese academy of sciences, Shanghai 2.0083.{2. 5 Purple Mountain Observatory, chinese academy of sciences, Nanjing 2.0008,{2. 6 Institute of High Energy Physics, chinese academy of sciences, beijing 100049,{2. 7{23., chinese academy of sciences, beijing 100190,{2. 1. National Astronomical Observatories Chinese Academy of Sciences Beijing 100012 China2. Institute of Geochemistry Chinese Academy of Sciences Guiyang 550002 China3. Xi’an Institute of Optics and Precision Mechanics Chinese Academy of Sciences Xi’an 710119 China4. Shanghai Institute of Technical Physics Chinese Academy of Sciences Shanghai 200083 China5. Purple Mountain Observatory Chinese Academy of Sciences Nanjing 210008 China6. Institute of High Energy Physics Chinese Academy of Sciences Beijing 100049 China7. Center for Space Science and Applied Research Chinese Academy of Sciences Beijing 100190 China

The strategic plan for the development of the unmanned chinese Lunar Exploration Program is characterized by three distinct stages: "orbiting around", "landing on" and "returning from" the Moon. The first chinese lunar probe, Chang'E-1, which was successfully launched on October 2.th, 2.07 at Xichang Satellite Launch {2., and guided to crash on the Moon on March 1st, 2.09, at 52.3.°E, 1.50°S, in the north of Mare Fecunditatis, is the first step towards the "orbiting around" stage. The Chang'E-1 mission lasted 495 days, exceeding the expected life-span by about four months. A total of 1.3. TB raw data was received from Chang'E-1. It was then processed into 4 TB scientific data products at various levels. Many scientific results have been obtained by analyzing these data, including especially the "global lunar image from the first chinese lunar explora- tion mission". All scientific goals of Chang'E-1 have been achieved. It provides much useful materials for further advances of lunar sciences and planetary chemistry. Meanwhile, these results will serve as a firm basis for future chinese lunar missions.

关键词： lunar orbiter Chang’E-1 scientific data results

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WIND observations of plasma waves inside the magnetic cloud boundary layers

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science Bulletin 2005年第18期 85-90页

作者： wei fengsi1 , ZHONG Dingkun1,2. FENG Xueshang1, YANG Fang1,2.& LIU Rui 1 1. SIGMA Weather Group, Laboratory for {2. Weather,{2.,{3., beijing 100080, china 2. Graduate School,{3., beijing 100049, china

Based on the WIND observational data for the plasma waves from thermal noise receptor (TNR) working on the frequency 4―2.6 kHz and the solar wind and the magnetic fields, we analyze the plasma wave activities in the 60 magnetic cloud’s boundary layers (BLs) and find that there are often various plasma wave activities in the BLs, which are different from those in the adjacent solar wind (SW) and the magnetic clouds (MC). The basic characteris-tics are that: (1) the enhancement of the Langmuir wave near the electronic plasma frequency (fpe) is a dominant wave ac-tivity, which occupies 75% investigated samples; (2. the events enhanced both in the langmuir and ion acustic (f 3. broadband, continuous enhancement events in the plasma wave activities were observed in the whole frequency band of TNR, and about 3.% of the 60 samples, however, were not observed in the SW and the MC investigated events; (4) although the ratio of the temperatures between the electon and proton, Te/Tp≤1, the ion caustic wave enhancement activities are still often observed in the BLs, which makes it difficult to ex- plain them by the traditional plasma theory. New results reported in this paper further show that the magnetic cloud’s BL is an important dynamic structure, which could provide useful diagnosis for understanding the cloud’s BL physics and could expand a space developing space plasma wave theory.

关键词： solar wind magnetic cloud boundary layer plasma waves.

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Enhancing electrochemical capacity and interfacial stability of lithium-ion batteries through side reaction modulation with ultrathin carbon nanotube film and optimized lithium cobalt oxide particle size

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Nano research 2024年第8期17卷 7230-7241页

作者： wei Xi Xiaogang Xia Jiacheng Zhu Dehua Yang Sishen xie beijing National Laboratory for Condensed Matter Physics and Institute of Physics Chinese Academy of SciencesBeijing 100190China School of Physical sciences University of Chinese Academy of SciencesBeijing 100049China Advanced Passivation Technology Lab College of Physics Science and TechnologyHebei UniversityBaoding 071002China

Lithium cobalt oxide(LCO),the first commercialized cathode active material for lithium-ion batteries,is known for high voltage and ***,its application has been limited by relatively low capacity and stability at high *** particle size is considered one of the most straightforward and effective strategies to enhance ion transfer,thus increasing the rate ***,side reactions are simultaneously enhanced as the specific surface area ***,we investigate the impact of LCO particles with varying size distributions and optimize the particle *** modulate the side reactions associated with particle size reduction,an ultrathin carbon nanotube film(UCNF)is introduced to coat the cathode *** this simple process and optimized particle size,the rate performance improves significantly,normal commercial LCO achieves 118 mA·h·g^(−1)at 3.0–4.3.V and 2. C(0.72.mA·h·cm^(−2.),corresponding to power density of 873.0}W·kg^(−1).This method is applied to high voltage as well,152.mA·h·g^(−1)at 3.0–4.6 V and 2. C(0.99 mA·h·cm^(−2.)was achieved with high-voltage LCO(HVLCO),corresponding to power density of 11,552.W·kg^(−1).The cycling stability is also enhanced,with the capacity retention maintaining more than 96%after 100 cycles at 0.1 *** the first time,UCNF is demonstrated to suppress the excessive decomposition of the electrolytes and solvents by blocking electron injection/extraction between LCO and electrolyte *** findings provide a simple method for improving LCO rate performance,especially at high C-rates.

关键词： lithium-ion batteries lithium cobalt oxides carbon nanomaterials side reactions

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Performance analysis of uplink MIMO MC-CDMA systems based on linear zero-forcing V-BLAST algorithm

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science in china(Series F) 2008年第9期51卷 1305-1318页

作者： YANG wei1,2.& YANG wei1 1 State Key Laboratory of Rail Traffic Control and Safety,{2. Jiaotong University,{2. 100044,{2. 2.National Mobile Communications {3. Laboratory,Southeast University,Nanjing 2.0096,{2. 1. State Key Laboratory of Rail Traffic Control and Safety Beijing Jiaotong University Beijing 100044 China 2. National Mobile Communications research Laboratory Southeast University Nanjing 210096 China

A structure was proposed for multiple-input-multiple-output multicarrier code divi- sion multiple access （MIMO MC-CDMA） uplink transmission system. Linear zero- forcing V-BLAST （ZF V-BLAST） algorithm and maximum ratio combining （MRC） scheme was applied to the receivers. The average bit error rate （BER） expression was derived on condition that the number of receive antennas was larger than that of transmit antennas and it was verified by simulations. Numerical results show that the number of transmit and receive antennas, as well as the number of sub- carriers, all exert significant effects on the BER performance. The space diversity and frequency diversity show different abilities to improve the BER performance. The MIMO MC-CDMA system based on linear ZF V-BLAST algorithm is capable of achieving better BER performance than that of the conventional MC-CDMA system by reducing the number of transmit antennas or increasing the number of receive antennas.

关键词： bit error rate(BER) multiple-input-multiple-output(MIMO) multicarrier code division multiple access(MC-CDMA) zero-forcing(ZF)

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Development and Application of Non-Quenched and Tempered Steel for Auto Forging Components in china

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Journal of Iron and Steel research International 2011年第S1期18卷 735-741页

作者： ZHANG Ying-jian 1,CHEN Si-lian 1,DONG Han 1,HUI wei-jun 1,PENG Jun 2.(1.Institute for Structural Materials,Central Iron & Steel research Institute,{2. 100081,{2. 2.School of Physical {3. and Technology,Yunnan University,Kunming 650091,Yunnan,{2.) Cent Iron & Steel Res Inst Inst Struct Mat Beijing 100081 Peoples R China Yunnan Univ Sch Phys Sci & Technol Kunming 650091 Yunnan Peoples R China

Non-quenched and tempered (NQT) steels have been applied for auto forging products at the aim of lower cost since 1980’s in *** quenching and tempering processes,the cost of heat treatment was greatly decreased,so they are widely applied in car forgings such as crankshaft,connecting ***,with the aim of improving performance and reducing production cost,new technologies,such as:reductions of microalloyed elements,microstructure refining,and mechanical properties forecast have been developed in{2. auto *** designation,processing,properties prediction and microstructure of auto components have been controlled *** the development of new technologies,NQT steel gradually began to be applied to product important parts,and replace Quenching and Tempering (QT) *** steel makers and end product users are expressed their desire to share benefits of technological *** technologies will have a huge developing space and very bright developing prospects in motor parts industry in future.

关键词： NQT steel microstructure and property forecast lower cost forging

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A simulation study on the semiannual variation of the ionospheric F2.layer zonal electric fields at the magnetic equator

A simulation study on the semiannual variation of the ionosp...

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中国科学院地质与地球物理研究所2.06学术年会

作者： Tao Yu,~(1,2. weixing Wan,~1 Libo Liu,~1 Xiaoyin Li,~3.XiaoLi Luan,~2.and wei Tang~2.1 Institute of Geology and Geophysics,{2. academy of {2.,{3.,china 2.National Centre for spaceweather,china Meteorological Administration,{3.,china 3.Centre for space {12. and applied research,{2. academy of {2.,{3.,china

With a theoretical model which yields ionospheric electric fields,we study the yearly variation of ionospheric electric fields at middle and low latitudes under the condition of low solar and quiet geomagnetic *** results show the following *** the ionospheric electric fields are calculated individually in the Northern(or Southern) Hemisphere without including the influence of the other hemisphere(uncoupled),the electric field in the Northern(or Southern) Hemisphere varies in an obvious annual pattern;when the electric field is calculated simultaneously in both hemispheres including the influence of the other hemispheres (coupled),the electric field varies in a predominantly semiannual ***,quite good consistency was found between the behaviors of semiannual variation calculated by our theoretical electric field model and an empirical model of Richmond et al.(1980).

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Effects of a hypogeomagnetic field on gravitropism and germination in soybean

Effects of a hypogeomagnetic field on gravitropism and germi...

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2.11年空间生命与生命起源暨航天医学工程学术研讨会

作者： wei-chuan Mo~(1,2.,Zi-jian Zhang~(1,2.,Ying Liu~(1,2.,Guang-jie Zhai~3. Yuan-da Jiang~3.Rong-qiao He~(1,2. 1 The State Key Laboratory of Brain and Cognitive sciences,Institute of Biophysics,{2. {2. of sciences,15 Datun Road,Chaoyang District,beijing 100101,china 2.Graduate University of the chinese academy of sciences,Yuquan Road,beijing 100049,china 3.15},{2. {2. of sciences,1 Zhongguancun Nanertiao Road,Haidian District,beijing 100190,china.

＜正＞Hypogeomagnetic field（HGMF）refers to a geomagnetic field（GMF）eliminated environment,which is one of the characteristic environmental factor in outer space. Any plants grown during long-term space missions will inevitably experience the hypogeomagnetic *** is possible that the innate adaptation of plants to the

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