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Asymptotic behavior of the divergence on loop spaces over a compact Riemannian manifold

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chinese science Bulletin 1998年第4期43卷 272-274页

作者： LI Xiangdong Probability laboratory, Institute of applied Mathematics, chinese academy of sciences, beijing 100080, china Probability laboratory Institute of Applied Mathematics Chinese Academy of Sciences Beijing China

The asymptotic behavior of the divergence on loop space is studied over a compact Riemannian manifold via quasi_sure analysis. A Sobolev estimate plays a crucial role.

关键词： divergence exponential integrability Sobolev estimate.

Lunar surface dielectric constant,regolith thickness, and ~3He abundance distributions retrieved from the microwave brightness temperatures of CE-1 Lunar Microwave Sounder

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science china Earth sciences 2010年第9期53卷 1365-1378页

作者： WANG ZhenZhan1, LI Yun1,2, JIANG JingShan1 & LI DiHui1 1 National Microwave Remote Sensing laboratory, center for space science and applied research, chinese academy of sciences, beijing 100190, china 2 Graduate University of chinese academy of sciences, beijing 100049, china National Microwave Remote Sensing laboratory Center for Space Science and Applied Research Chinese Academy of Sciences Beijing China Graduate University of chinese academy of sciences Beijing China

Lunar regolith parameters, such as physical temperature, thickness and dielectric constant, are important in studying regolith features, distribution of lunar resources and evolution of the Moon. There had been no measurement obtained by lunar-orbit-borne microwave radiometer applied to evaluate the properties of lunar regolith before CE-1 Lunar Microwave Sounder (CELMS) being launched. CEMLS is the first passive microwave radiometer in the world to sound the surface of the Moon. The brightness temperatures (TB) sensed by CELMS include complicated information on the above geophysical parameters. In this paper, algorithms of retrieving dielectric constant, regolith thickness, and 3He content from CELMS brightness temperatures are developed, and the results are compared with those from literature. The results show that the regolith thicknesses are mostly in the range of 4.0-6.0 m, and 43% of them are bigger than 5.0 m. The content of 3He evaluated by retrieved regolith thickness is about 1.03 million tons.

关键词： CE-1 Lunar Microwave Sounder (CELMS) lunar regolith dielectric constant lunar regolith thickness 3He retrieval

Correlative ionospheric disturbances in the sunlit hemisphere during the flare on July 14,2000

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chinese science Bulletin 2002年第12期47卷 975-977页

作者： ZHANG Donghe & XIAO ZuoDepartment of Geophysics, Peking University, beijing 100871, china Qingdao research center, chinese research Institute of Radio-wave Propagation, Qingdao 266071, china center for space science and applied research, chinese academy o Department of Geophysics Peking University Beijing China Qingdao research center Chinese Research Institute of Radio-wave Propagation Qingdao China center for space science and applied research Chinese Academy of Sciences Beijing China

Using GPS data obtained from GPS sites located on the sunlit hemisphere during the flare on July 14, 2000, the ionospheric response to the flare was analyzed. A kind of tiny correlative ionospheric fluctuations were revealed from the temporal total electron content (TEC) curves derived from GPS measurements, and the values of this kind of disturbances are about 1015 m-2. A comparative analysis of these disturbances and soft X-ray flux detected at GOES satellite during the flare is done. It is found that this kind of disturbances revealed in the temporal TEC curves did occur in a very large area of sunlit ionosphere and its behavior is mainly controlled by the characteristics of the flare’s extra radiation. Because the similar fluctuations are not found in the curve of soft X-ray flux, it is concluded that the flare extra radiation in EUV band should have corresponding fluctuations and it is the fluctuations that cause the TEC disturbances. The height, where the disturbances occur, should be in the F

关键词： GPS TEC flare correlative disturbance.

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, china Graduate University of chinese academy of sciences, beijing 100039, china State Key lab of Systems Ecology, research center for Eco-Environmental sciences, chinese academy of sciences, beijing 100085, china Institute of applied Ecology Chinese Academy of Sciences Shenyang China Graduate University of chinese academy of sciences Beijing China State Key lab of Systems Ecology Research Center for Eco-Environmental Sciences Chinese Academy of Sciences Beijing 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.

A new algorithm for microwave radiometer remote sensing of sea surface salinity and temperature

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science china Earth sciences 2006年第11期49卷 1204-1211页

作者： YIN Xiaobin1, LIU Yuguang1, WANG Zhenzhan2 & XIU Peng1 1. Physical Oceanography laboratory, Ocean University of china, Qingdao 266003, china 2. center for space and applied research, chinese academy of sciences, beijing 100080, china Physical Oceanography laboratory Ocean University of China Qingdao China center for space and applied research Chinese Academy of Sciences Beijing China

The microwave radiation of the sea surface, which is denoted by the sea surface brightness temperature, is not only related with sea surface salinity (SSS) and temperature (SST), but also influenced by sea surface wind. The errors of wind detected by satellite sensor have significant influences on the accuracy of SSS and SST retrieval. The effects of sea surface wind on sea surface brightness temperature, i.e. △Th,v, and the relations among △Th,v, wind speed, sea surface tempera- ture, sea surface salinity and incidence angle of observation are investigated. Based on the investi- gations, a new algorithm depending on the design of a single radiometer with double polarizations and multi-incidence angles is proposed. The algorithm excludes the influence of sea surface wind on SSS and SST retrieval, and provides a new method for remote sensing of SSS and SST.

关键词： microwave radiometer, sea surface temperature, sea surface salinity, wind, brightness temperature.

Latest progress on interactions between VLF/ELF waves and energetic electrons in the inner magnetosphere

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science china Earth sciences 2010年第3期53卷 317-326页

作者： XIAO FuLiang1,2, ZONG QiuGang3, SU ZhenPeng4, TIAN Tian3 & ZHENG HuiNan4 1 School of Physics and Electronic sciences, Changsha University of science and Technology, Changsha 410004, china 2 State Key laboratory of space weather, chinese academy of sciences, beijing 100190, china 3 Institute of space Physics and applied Technology, Peking University, beijing 100871, china 4 CAS Key lab for Basic Plasma science, School of Earth and space sciences, University of science and Technology of china, Hefei 230026, china School of Physics and Electronic sciences Changsha University of Science and Technology Changsha China State Key laboratory of space weather Chinese Academy of Sciences Beijing China Institute of space Physics and applied Technology Peking University Beijing China CAS Key lab for Basic Plasma science School of Earth and Space Sciences University of Science and Technology of China Hefei China

Interactions between very/extremely low frequency (VLF/ELF) waves and energetic electrons play a fundamental role in dynamics occurring in the inner magnetosphere. Here, we briefly discuss global properties of VLF/ELF waves, along with the variability of the electron radiation belts associated with wave-particle interactions and radial diffusion. We provide cases of electron loss and acceleration as a result of wave-particle interactions primarily due to such waves, and particularly some preliminary results of 3D evolution of phase space density from our currently developing 3D code. We comment on the existing mechanisms responsible for acceleration and loss, and identify several critical issues that need to be addressed. We review latest progress and suggest open questions for future investigation.

关键词： wave-particle interaction VLF/ELF waves energetic electrons acceleration and loss inner magnetosphere

Propagation of interplanetary shock excited ultra low frequency (ULF) waves in magnetosphere-ionosphere-atmosphere——Multi-spacecraft “Cluster” and ground-based magnetometer observations

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science china(Technological sciences) 2010年第9期53卷 2528-2534页

作者： WANG ChengRui1,2,ZONG QiuGang1,3 & WANG YongFu1 1 Institute of space Physics and applied Technology,Peking University,beijing 100871,china 2 Sate Key laboratory of space weather,chinese academy of sciences,beijing 100190,china 3 center for Atmospheric research,600 Suffolk Street,University of Massachusetts Lowell,MA 01854,USA Institute of space Physics and applied Technology Peking University Beijing China Sate Key laboratory of space weather Chinese Academy of Sciences Beijing China center for Atmospheric research University of Massachusetts Lowell USA

The ultra low frequency (ULF) wave in magnetosphere can act as an important means for solar wind energy inward *** paper quantitatively analyzes the propagation process of the ULF wave triggered by the interplanetary shock propagating from inner magnetosphere equatorial plane along magnetic field lines to the top of the ionosphere and below ionosphere propagating process and establishes a relatively complete magnetosphere-ionosphere-atmosphere propagation model which can be used to study the relationship between the amplitude of the ULF waves triggered by the interplanetary shock wave in magnetospheric space and the magnetic effect caused by the ULF *** a comparison with recent observations,we found that: in the event during November 7,2004 that an interplanetary shock wave interacted with the magnetosphere,Cluster satellites observed that electric field fluctuations and the band-pass filtered result of ground stations meridional component had similar *** with the geomagnetic measurement near the footprints,we found that the electric field disturbance in the magnetosphere spread along the ground magnetic field lines in the form of the ULF waves and changed into geomagnetic *** result reveals that the ULF wave is in contact with the ground geomagnetic *** ULF waves couple with ionized components in ionosphere and spread to the ground in the form of electromagnetic *** this research,we believe that the magnetosphere,ionosphere and ground magnetic effects caused by interplanetary shock wave are the same physical phenomena responding in different *** on the overall consideration of entire electromagnetic response to the interplanetary shock wave,we found that the correlation between CLUSTER multi-satellite observation and geomagnetic station observation is due to the ULF wave propagated in magnetosphere-ionosphere-atmosphere system,and we quantitatively interpreted this response process

关键词： ultra low frequency (ULF) wave magnetic storm ionosphere IRI model interplanetary shock

On some tests-based projection pursuit for elliptical symmetry of a high-dimensional distribution

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chinese science Bulletin 1998年第6期43卷 450-458页

作者： JING Ping 1 and ZHU Lixing 2 1. Mathematics lab, china University of Mining & Technology, beijing 100083, china 2. Probability lab, Institute of applied Mathematics, chinese academy of sciences, beijing 100080, china Mathematics lab China University of Mining & Technology Beijing China Probability lab Institute of Applied Mathematics Chinese Academy of Sciences Beijing China

Some test statistics of Kolmogorov type and Cramér-von Mises type based on projection pursuit technique are proposed for the testing problem of sphericity of a high-dimensional distribution. The limiting distributions of the test statistics are derived under the null hypothesis and under any fixed alternative. The asymptotic properties of bootstrap approximation are investigated. Furthermore, for computational reasons, an approximation for the statistics, based on the number theoretic method, is suggested.

关键词： bootstrap approximation projection pursuit type statistic elliptical symmetry.

The roles of a decision support system in applying forest ecosystem management in Northeast china

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science china(Technological sciences) 2006年第Z1期49卷 9-18页

作者： DAI Limin, ZHENG Bofu, Guofan Shao & ZHOU Li State Key lab of Systems Ecology, research center for Eco-Environmental sciences, chinese academy of sciences, beijing 100085, china Institute of applied Ecology, chinese academy of sciences, Shenyang 110016, china Department of Forestry and Natural Resources, Purdue University, West Lafayette, IN 47907, USA Graduate University of chinese academy of sciences, beijing 100101, china State Key lab of Systems Ecology Research Center for Eco-Environmental Sciences Chinese Academy of Sciences Beijing China Institute of applied Ecology Chinese Academy of Sciences Shenyang China Department of Forestry and Natural Resources Purdue University West Lafayette USA Graduate University of chinese academy of sciences Beijing China

Forest ecosystems provide a variety of services and forest ecosystem management (FEM) is an effective approach to maximize the services. Because of the complexity of forest ecosystems, the applications of FEM can be facilitated with decision support systems (DSS) that recognize and incorporate ecological and socio-economic variables. With the rapid development of computation and information technologies, DSS have been advanced in many ways. Traditional forest management within a forestry unit in china is planned on a yearly basis. The planning itself remains primarily a verbal concept as there are no quantitative decision-support tools available to translate the concept into forest management actions. For the purposes of FEM at the management level, a forest management DFF, FORESTAR, has been developed under a framework of geographic information system (GIS) and forest models. The paper explained the intelligent modeling mechanisms and demonstrated how the applications of FEM can be strengthened with the applications of FORESTAR.

关键词： forest functions, forested landscapes, forest services, forest models, geographic information systems.