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Distributed modeling of the beginning and ending dates and durations of limited temperatures over the rugged terrain of Chongqing

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Progress in Natural Science:Materials International 2009年第12期19卷 1739-1746页

作者： Xinfa Qiu~a,Guoping Shi~a,Yan Zeng~(b,*),Zongya Bian~a,Jingmei Wei~c a Department of GIS,school of Remote Sensing,nanjing {2. of information Science & technology,nanjing 2.0044,china b Jiangsu Institute of Meteorological Sciences,nanjing 2.0008,china c Jinling College,nanjing {2.,nanjing 2.0089,china Department of GIS School of Remote Sensing Nanjing University of Information Science & Technology Nanjing 210044 China Jiangsu Institute of Meteorological Sciences Nanjing 210008 China Jinling College Nanjing University Nanjing 210089 China

A physically based empirical model was established for the beginning and ending dates(BED) of limited *** used were daily mean temperatures from 34 conventional stations in the Chongqing region,measured from 1961 to *** this model in combination with the distributed modeling results of monthly mean temperatures,we developed a method for creating a distributed simulation of the BED and durations of limited temperatures in the rugged terrain of *** distribution maps were generated at a resolution of 100×100 m for the BED and durations of the limited temperatures of 0,10,15 and *** suggest that the distributed model is able to successfully reveal the macroscopic trends and local *** the modeled BED,the mean absolute bias error is 0.6-2.4 d. Cross-validation and case-year tests show mean absolute bias errors of 1.3-2.8 d and 0.7-2.5 d,*** shows that the simulation results are consistent with the field *** implies that the simulations are as good as observations,thus providing a viable technique for simulating mountainous heat resources using conventional meteorological data.

关键词： Distributed modeling Chongqing Limited temperature Beginning and ending date

Large-Eddy Simulations of turbulent flows with lattice Boltzmann dynamics and dynamical system sub-grid models

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Science china(Technological Sciences) 2009年第3期52卷 670-679页

作者： GUAN Hui1 & WU ChuiJie2.1 Research Center for Fluid Dynamics, PLA university of Science and technology, {2. 2.1101, china 2.school of Aeronautics and Astronautics, Dalian university of technology, Dalian 11602., china Research Center for Fluid Dynamics PLA University of Science and Technology Nanjing China school of Aeronautics and Astronautics Dalian University of Technology Dalian China

In this paper, two sub-grid scale (SGS) models are introduced into the Lattice Boltzmann Method (LBM), i.e., the dynamics SGS model and the dynamical system SGS model, and applied to numerically solving three-dimensional high Re turbulent cavity flows. Results are compared with those obtained from the Smagorinsky model and direct numerical simulation for the same cases. It is shown that the method with LBM dynamics SGS model has advantages of fast computation speed, suitable to simulate high Re turbulent flows. In addition, it can capture detailed fine structures of turbulent flow fields. The method with LBM dynamical system SGS model dose not contain any adjustable parameters, and can be used in simulations of various complicated turbulent flows to obtain correct information of sub-grid flow field, such as the backscatter of energy transportation between large and small scales. A new average method of eliminating the inherent unphysical oscillation of LBM is also given in the paper.

关键词： Large-Eddy Simulation Lattice Boltzmann Method dynamics sub-grid scale model dynamical system sub-grid scale model parallel computation

Weak martingale Hardy spaces and weak atomic decompositions

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Science china mathematics 2006年第7期49卷 912-921页

作者： HOU Youliang & REN Yanbo school of mathematics and Statistics, Wuhan {2., Wuhan 430072. china Department of mathematics & physics, Henan {2. of Science and technology, Luoyang 471003, china school of mathematics and Statistics Wuhan University Wuhan China Department of mathematics & physics Henan University of Science and Technology Luoyang China

In this paper we define some weak martingale Hardy spaces and three kinds of weak atoms. They are the counterparts of martingale Hardy spaces and atoms in the classical martingale Hp-theory. And then three atomic decomposition theorems for martingales in weak martingale Hardy spaces are proved. With the help of the weak atomic decompositions of martingale, a sufficient condition for a sublinear operator defined on the weak martingale Hardy spaces to be bounded is given. Using the sufficient condition, we obtain a series of martingale inequalities with respect to the weak Lp-norm, the inequalities of weak (p ,p)-type and some continuous imbedding relationships between various weak martingale Hardy spaces. These inequalities are the weak versions of the basic inequalities in the classical martingale Hp-theory.

关键词： martingale, weak Hardy space, weak atom, atomic decomposition.

COLLECTIVELY COMPACT COMPOSITION OPERATOR SEQUENCES BETWEEN BERGMAN AND HARDY SPACES

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Acta Mathematica Scientia 2004年第2期24卷 206-212页

作者：王茂发刘培德 schoolofmathematicsandStatistics WuhanUniversityWuhan430072China

This paper studies the collective compactness of composition operator sequences between the Bergman and Hardy spaces. Some sufficient and necessary conditions involving the generalized Nevanlinna counting functions fo... 详细信息

关键词： Bergman space Hardy space composition operator collectively compact operator sequence

A semiparametric Wald statistic for testing logistic regression models based on case-control data

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Science china mathematics 2008年第11期51卷 2020-2032页

作者： WAN ShuWen Biostatistics Lab, school of Life Sciences, nanjing {2., nanjing 2.0093, china Biostatistics Lab School of Life Sciences Nanjing University Nanjing China

We propose a semiparametric Wald statistic to test the validity of logistic regression models based on case-control data. The test statistic is constructed using a semiparametric ROC curve estimator and a nonparametric ROC curve estimator. The statistic has an asymptotic chi-squared distribution and is an alternative to the Kolmogorov-Smirnov-type statistic proposed by Qin and Zhang in 1997, the chi-squared-type statistic proposed by Zhang in 1999 and the information matrix test statistic proposed by Zhang in 2.01. The statistic is easy to compute in the sense that it requires none of the following methods: using a bootstrap method to find its critical values, partitioning the sample data or inverting a high-dimensional matrix. We present some results on simulation and on analysis of two real examples. Moreover, we discuss how to extend our statistic to a family of statistics and how to construct its Kolmogorov-Smirnov counterpart.

关键词： case-control data density ratio model empirical likelihood Kolmogorov-Smirnov statistic logistic regression ROC curve 30P12 32.12

Application of Fourier Slice Theorem in Wigner Operator Theory and New Complete Representation

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Communications in Theoretical physics 2009年第11期52卷 829-831页

作者： WANG Tong-Tong~1 and FAN Hong-Yi~(2.3)1 school of mathematics and {2., Huangshi Institute of technology, Huangshi 435003, china2.Department of Material Science and Engineering, university of Science and technology of china, Hefei 2.002., china3 Department of {2., Shanghai Jiao Tong university, Shanghai 2.0030, china school of mathematics and {2. Huangshi Institute of Technology Huangshi 435003 China Department of Material Science and Engineering University of Science and Technology of China Hefei 230026 China Department of physics Shanghai Jiao Tong University Shanghai 200030 China

By applying the Fourier slice theorem,S;（λ）=∫;P;（t）e;=F（λcosθ,λsinθ）,where P;（t）is aprojection of f（x,p）=（?）F（u,v）e;dudv along lines of constant,to the Wigner operator we are naturally led toa projection operator（pure state）,which results in a new complete *** Weyl orderimg formalism of theWigner operator is used in the derivation.

关键词： Wigner operator Fourier slice theorem new complete representation

Restrictive mechanism of flow control among non-cooperative Internet users

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Science china(information Sciences) 2011年第1期54卷 12-22页

作者： TAO Jun1,2.ZHONG Xiao1,2.& LU YiFei1,2.1Key Laboratory of Computer Network and information Integration,Southeast university, Ministry of Education,{2. 2.0096,china 2.4} of Computer Science and Engineering,Southeast university,{2. 2.0096,china Key Laboratory of Computer Network and information Integration Southeast University Ministry of Education Nanjing China school of Computer Science and Engineering Southeast University Nanjing China

The flow and congestion control methods based on one-shot game model with non-cooperative game theory can explain the non-cooperative behavior of Internet ***,the low effciency of equilibrium solutions affects their *** the behavior of flow and congestion control based on infinitely repeated game models is addressed;the repeated and infinitely repeated flow and congestion control game model is presented; the existence and optimization of the Nash equilibrium point are proved;the discount factor in repeated game is discussed;the punishment and threat strategy to users'misbehavior is studied in N-users infinitely flow control game;the punishment restrictive method of users'behavior is designed in infinitely and finitely games;finally,a flow control algorithm based on repeated game,FCAR,is provided based on the conclusions of repeated game *** results of experiment and simulation show that FCAR algorithm could regularize and restrict users' misbehavior *** algorithm can also make non-cooperative Internet users achieve cooperation in order to optimize the utility of the whole flow and congestion control system.

关键词： Nash equilibrium utility infinitely and finitely repeated game flow and congestion control

Asymptotic SEP of MIMO beamforming in two-hop AF relaying systems

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Science china(information Sciences) 2012年第2期55卷 377-383页

作者： FU YouHua1,HAN YuJie2.YANG LvXi2.ZHU WeiPing3 & LIU Chen1 1school of Electronic Science and Engineering,nanjing {2. of Posts and Telecommunications,nanjing 2.0003,china 2.0} of information Science and Engineering,Southeast {2.,nanjing 2.0096,china 3Department of Electrical and Computer Engineering,Concordia {2.,Montreal H3G 1M8,Canada school of Electronic Science and Engineering Nanjing University of Posts and Telecommunications Nanjing China school of information Science and Engineering Southeast University Nanjing China Department of Electrical and Computer Engineering Concordia University Montreal Canada

This paper derives an asymptotic average symbol error probability(SEP)expression for multiple-input multiple-output(MIMO)two-hop amplify-and-forward(AF)relay systems with optimal *** analysis at high signal-to-noise ratio(SNR)quantifies the diversity order and array gain,which are valid for any antenna numbers of the terminals and arbitrary channel fading *** is also proved that the system performance is dominated by the relatively degraded one of the two-hop *** results based on the simple expressions provide valuable insights into the performance and practical design considerations of MIMO AF networks.

关键词： MIMO relay networks optimal beamforming symbol error probability(SEP) diversity order

Normal scalar curvature and a pinching theorem in S^m×R and H^m×R

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Science china mathematics 2011年第9期54卷 1977-1984页

作者： CHEN Qun 1,2.& CUI Qing 3,1,1 school of mathematics and Statistics,Wuhan {2.,Wuhan 430079,china 2.International Center for Theoretical physics,Trieste 34100,Italy 3 school of mathematics,Southwest Jiaotong {2.,Chengdu 610031,china school of mathematics and Statistics Wuhan University Wuhan China International Center for Theoretical physics Trieste Italy school of mathematics Southwest Jiaotong University Chengdu China

We obtain an inequality in Sm×R and Hm×R which is similar to DDVV *** an application,we show that a minimal submanifold in H m×R with nonnegative scalar curvature must be a surface of the type γ×R,where γ is a g... 详细信息

关键词： product spaces DDVV conjecture pinching theorem