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Chinese Annals of Mathematics,Series B 2000年第4期21卷 511-524页

作者： RENYONGCAI LIXIANGYANG DepartmentofMathematics SichuanUniversityChengdu610064China. DepartmentofBasicSciences ChengduInstituteofMeteorologyChengdu610041China.

Let G be a nonabelian finite group. Then Irr(G/G’) is an abelian group under the multiplication of characters and acts on the set of non-linear irreducible characters of G via the multiplication of characters. The purpose of this paper is to establish some facts about the action of linear character group on non-linear irreducible characters and determine the structures of groups G for which either all the orbit kernels are trivial or the number of orbits is at most two. Using the established results on this action, it is very easy to classify groups G having at most three non-linear irreducible characters.

关键词： Finite group Character Action Orbit

Fractionation of Heavy Metals in Sediments from Dianchi Lake,china

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Pedosphere 2007年第2期17卷 265-272页

作者： LI Ren-Ying YANG Hao ZHOU Zhi-Gao Lü Jun-Jie SHAO Xiao-Hua JIN Feng State Key Laboratory of Soil and Sustainable Agriculture Institute of Soil Science Chinese Academy of Sciences Nanjing 210008 （China）. College of Geography Science Nanjing Normal University Nanjing 210097 （China） Department of Applied meteorology Nanjing University of Information Science ＆ Technology Nanjing 210044 （China）

Fractionation of heavy metals in sediments can help in understanding potential hazards of heavy metals. The present study analyzed total concentrations and fractions of selected heavy metals （Cd, Cr, Cu, Pb, and Zn） in surface sediments from Dianchi Lake, Yunnan Province, china, as well as factors that may affect distributions of the various heavy metal fractions. Total concentrations of the heavy metals decreased in the order Zn 〉 Cu 〉 Pb 〉 Cr 〉 Cd. These heavy metals, except Cr, were much higher than their background levels, indicating that Dianchi Lake was polluted by Cd, Zn, Pb, and Cu. Cadmium occurred mainly as the non-residual fraction （sum of the HOAc-soluble, reducible, and oxidizable fractions）（97.6%）, and Zn （55.7%） was also predominantly found in the non-residual fraction. In contrast, most of the Cr （88.5%）, Pb （81.8%）, and Cu （59.2%） occurred in the residual fraction. Correlation analysis showed that total heavy metal concentrations, organic matter and reducible Fe were the main factors affecting the distributions of the various heavy metal fractions. In the Walhai section of Dianchi Lake （comprising 97% of the lake area）, the concentrations of Cd, Zn, Pb, and Cu in the non-residual fraction were significantly lower （P ≤ 0.01 or 0.05） than those of the Caohal section （3% of the lake area）. This indicated that potential heavy metal hazards in the Caohai section were greater than the Waihai section.

关键词： Dianchi Lake heavy metal fractions lake sediment organic matter reducible Fe

Study on Reconstruction of Heat Flux in Moving Boundary

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Study on Reconstruction of Heat Flux in Moving Boundary

Modeling the impact of Australian Plate drift on Southern Hemisphere climate and environment

2012 National Conference on Information Technology and Computer Science

作者： Zhijian Wu institute of meteorology and Oceangraphy PLA University of Science Technology nanjing,china Jing Feng institute of meteorology and Oceangraphy PLA University of Science Technology nanjing,china Xueyan Zhang institute of meteorology and Oceangraphy PLA University of Science Technology nanjing,china Aixia Zhou institute of meteorology and Oceangraphy PLA University of Science Technology nanjing,china

The initial boundary value problem for parabolic equation with Neumann boundary condition is a kind of classical problem in partial differential *** this paper,we consider a heat inverse problem with moving *** introducing a density function for potential method,thisproblem is essentially converted into solving an integral equation of the first kind with respect to the density function,which can be solved by the Tikhonov regularizing *** function method is used to determine the regularizing *** results are presented to support our inversion schemes.

关键词： heat equation potential scheme heat flux regularization numerics

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Chinese Science Bulletin 2005年第14期50卷 1495-1502页

作者： ZHOU Botao1,5, ZHAO Ping2, JIAN Zhimin3 & HE Jinhai4 1. Nansen-Zhu International Research Center, institute of Atmospheric Physics, Chinese Academy of Sciences, Beijing 100029, china 2. institute of Climate and Environment, Chinese Academy of Meteoro- logical Sciences, Beijing 100081, china 3. Laboratory of Marine Geology, Tongji University, Shanghai 200092, china 4. Department of Atmospheric Sciences, nanjing institute of Meteorol- ogy, nanjing 2..044, china 5. Graduate School of the Chinese Academy of Sciences, Beijing 100039, china Nansen-Zhu International Research Center Institute of Atmospheric Physics Chinese Academy of Sciences Beijing China Graduate School of the Chinese Academy of Sciences Beijing China institute of Climate and Environment Chinese Academy of Meteorological Sciences Beijing China Laboratory of Marine Geology Tongji University Shanghai China Department of Atmospheric Sciences Nanjing Institute of Meteorology Nanjing China

Using a global atmosphere-ocean coupled model with the present-day and 14 MaB.P. oceanic topogra- phy respectively, two experiments are implemented to inves- tigate the effect of different locations of Australian Plate on the atmospheric circulation in middle-high latitudes of the Southern Hemisphere. The results show that when Austra- lian Plate lay south at 14 MaB.P., both anticyclone circula- tions in the subtropical oceans and cyclone circulation around 60°-70°S are strengthened. Subtropical highs and circumpolar low pressure appear stronger, which results in much stronger Antarctic Oscillation and shorter period of Antarctic Oscillation Index (AOI) at 14 MaB.P. The rainfall and the surface air temperature also change correspondingly. The precipitation decreases around 40°S and increases around 60°-70°S, and the surface air temperature rises in high latitudes of the South Pacific and descends over the Weddell Sea and its north side. Besides, due to the changes of the temperatures and winds, Antarctic sea ice coverage also changes with its increasing in the Ross Sea and its west re- gions and decreasing in the Weddell Sea.

关键词：半球气候地球环球澳大利亚漂流物海洋地形学

Forecasting Nonlinear Time Series with Genetic Algorithms Genetic Algorithms and Symbolic Form

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Forecasting Nonlinear Time Series with Genetic Algorithms Ge...

正则化方法同化多普勒天气雷达资料及对降雨预报的影响

2010 Second IITA International Conference on Geoscience and Remote Sensing (IITA-GRS 2010)

作者： Sheng Zheng institute of meteorology PLA university of science of technology nanjing china Zhao Xiao-feng institute of meteorology PLA university of science of technology nanjing china

A genetic algorithm（GA） programmed to approximate the functional relation,in symbolic form,that describes the behavior of a time *** GA formalism proposed here utilizes the ’’postfix’’ representation with a view to reduce the procedural complexities and the "elitist mating’’ scheme to produce fitter offspring *** initial population of potential solutions is subjected to an evolutionary process described by selection,reproduction and mutation processes which are repeated over generations until an optimum individual is finally *** GA was proved useful in obtaining functional forms describing accurately the evolution of the nonlinear time series.

关键词： genetic algorithm forecasting nonlinear time series.

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物理学报 2011年第7期60卷 875-886页

作者：赵延来黄思训杜华栋仲跻芹中国人民解放军理工大学气象学院南京211101 中国气象局北京城市气象研究所北京100089

基于三维变分同化(3DVAR)的思想,提出一种适用于多普勒天气雷达资料直接同化的正则化方法.从寻求Yo=H(X)带有偏差δ的极小模解出发,引入正则化思想,并给出与3DVAR方案不同的新代价函数.针对2008年8月14日发生在北京地区的一次局地暴雨过... 详细信息

基于三维变分同化(3DVAR)的思想,提出一种适用于多普勒天气雷达资料直接同化的正则化方法.从寻求Yo=H(X)带有偏差δ的极小模解出发,引入正则化思想,并给出与3DVAR方案不同的新代价函数.针对2008年8月14日发生在北京地区的一次局地暴雨过程,设计了一组数值试验,并采用L曲线准则后验选取最优正则化参数.数值结果表明:正则化方法和3DVAR方案均能有效同化多普勒雷达资料,雷达径向速度的同化效果明显好于反射率因子;正则化参数取值越小,分析场增量越明显,同化进入初始场的中小尺度信息越多,分析场与观测场越接近;同化得到的分析场,能够在一定程度上缩短模式起转调整时间,提高短期降雨预报的准确率,其中最优选取正则化参数的同化试验能够延长雷达资料同化时效,进一步改善降雨预报效果,合理雨区雨带分布,相应得到的TS评分也更高.

关键词：多普勒雷达资料正则化 3DVAR 降雨预报

Preliminary study on assessment of nutrient transport in the Taihu Basin based on SWAT modeling

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Science china Earth Sciences 2006年第Z1期49卷 135-145页

作者： LAI Geying, YU Ge & GUI Feng nanjing institute of Geography & Limnology, Chinese Academy of Sciences, nanjing 210008, china The Graduate School of the Chinese Academy of Sciences, Beijing 100039, china Key Lab of Poyang Lake Ecological Environment and Resource Development, Jiangxi Normal University, Nanchang 330027, china nanjing institute of Geography & Limnology Chinese Academy of Sciences Nanjing China The Graduate School of the Chinese Academy of Sciences Beijing China Key Lab of Poyang Lake Ecological Environment and Resource Development Jiangxi Normal University Nanchang China

With the Taihu Basin as a study area, using the spatially distributed and mechanism-based SWAT model, preliminary simulations of nutrient transport in the Taihu Basin during the period of 1995～2002 has been carried out. The topography, soil, meteorology and land use with industrial point pollution discharge, the loss of agricultural fertilizers, urban sewerage, and livestock drainages were all considered in the boundary conditions of the simulations. The model was calibrated and validated against water quality monitoring data from 2001 to 2002. The results show that the annual total productions of nitrogen (TN) and phosphorus (TP) into Lake Taihu are 40000t and 2000t respectively. Nutrient from the Huxi Region is a major resource for Lake Taihu. The non-point source (surface source) pollution is the main form of catchment sources of nutrients into Lake Taihu,occupied TN 53% and TP 56% respectively. TN and TP nutrients from industrial point pollution discharge are 30% and 16%, and sewerage in both forms of point source and non-point source are TN 31% and TP 47%. Both the loss of agricultural fertilizers and livestock drainages from the catchment should be paid more attention as an important nutrient source. The results also show that SWAT is an effective model for the simulation of temporally and spatially nutrient changes and for the assessment of the trends in a catchment scale.

关键词： Taihu Basin, nutrients, catchment resource inputs, SWAT model, simulation.

Using directional data method for analysis on typhoon movement and its probability distribution features

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Acta Oceanologica Sinica 1988年第4期7卷 496-501页

作者： Shi Jiuen, Chen Xiaoming and Xiang Jingtian Beijing institute of meteorology, Beijing, chinainstitute of Applied Mathematics, Acadcmia Sinica, Beijing, china Beijing institute of meteorology Beijing China China

In many scientific fields such as meteorology, biology, geography, oceanography and astronomy, the angle value is very important, for example, wind directions, and the directions on which animals and birds migrate. This kind of data is called as directional data. In some problems, it is not expressed as 'angle' value, such as month by month mean temperature, however, it can be changed into a directional data through some transformations. The statistical method of directional data means that the methods of mathematical statistics are used in the treatment of directional data. In this way, data are considered as the points on two-dimensional cycle or higher dimensional sphere. Therefore, this method can also be called statistics on sphere. Because of its own characteristical feature, the statistics of directional data much differ from common statistics. Up to now, research work in this field has just started in china. In this paper, a statistical study on typhoon moving directions after their formation ov

关键词： Using directional data method for analysis on typhoon movement and its probability distribution features data

Accuracy of empirical and paraboloid magnetic field models estimated by Cluster magnetic data

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Accuracy of empirical and paraboloid magnetic field models e...

On the relationship between convection intensity of South china Sea summer monsoon and air-sea temperature difference in the tropical oceans

第十二届全国日地空间物理学术讨论会

作者： ZHANG Xiao-fang~1 FU Yang~2 YAN Wei~1 (1.meteorology institute,PLA Science and Technology University,nanjing 211101,china 2.Beijing institute of Applied meteorology,Beijing 100029,china)

＜正＞Cluster Ⅱ passing through the Birkeland current regions and the ring current inbetween,this paper compares the empirical magnetic field model T96、T01 and the paraboloid model A2000 with Cluster Ⅱ magnetic ***...

关键词：

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Acta Oceanologica Sinica 2004年第2期23卷 267-278页

作者： LINAilan LIANGJianyin GUDejun WANGDongxiao GuangzhouinstituteofTropicalandMarinemeteorologyofchinaMeterologicalAdministration Guangzhou510080China KeyLaboratoryofTropicalMarineEnviromentaldynamics SouthChinaSeaInstituteofOceanologyChineseAcademyofSciencesGuangzhou510301China

The annual, interannual and inter-decadal variability of convection intensity of South china Sea (SCS) summer monsoon and air-sea temperature difference in the tropical ocean is analyzed, and their relationship is discussed using two data sets of 48-a SODA (simple ocean data assimilation) and NCEP/NCAR. Analyses show that in wintertime Indian Ocean (WIO), springtime central tropical Pacific (SCTP) and summertime South china Sea-West Pacific (SSCSWP), air-sea temperature difference is significantly associated with the convection intensity of South china Sea summer monsoon. Correlation of the inter-decadal time scale (above 10 a) is higher and more stable. There is inter-decadal variability of correlation in scales less than 10 a and it is related with the air-sea temperature difference itself for corresponding waters. The inter-decadal variability of the convection intensity during the South china Sea summer monsoon is closely related to the inter-decadal variability of the general circulation of the atmosphere. Since the late period of the 1970s, in the lower troposphere, the cross-equatorial flow from the Southern Hemisphere has intensified. At the upper troposphere layer, the South Asian high and cross-equatorial flow from the Northern Hemisphere has intensified at the same time. Then the monsoon cell has also strengthened and resulted in the reinforcing of the convection of South china Sea summer monsoon.

关键词： tropical oceans air-sea temperature difference South china Sea summer monsoon convection, Convec-tion intensity