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ANALYTICAL SOLUTION OF NONLINEAR BAROTROPIC VORTICITY EQUATION

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Journal of Hydrodynamics 2008年第4期20卷 530-535页

作者： WANG Yue-peng SHI Wei-hl college of mathematics and Physics Nanjing University of Information Science and Technology Nangjing210044 China Jiangsu Key Laboratory of Meteorological Disaster Nangjing University of Information Science and Technology Nangjing 210044 China Department of mathematics Shanghai University Shanghai 200072 China

The C^k （k ≥ 3） stability of nonlinear barotropic vorticity equation was proved. The necessary and sufficient conditions for the initial value problem to be well-posed were presented. Under the conditions of well-p... 详细信息

关键词： nonlinear barotropic vorticity equation stability well-posedness analytical solution

TRANSIENT QUEUE SIZE DISTRIBUTION SOLUTION OF GEOM/G/1 QUEUE WITH FEEDBACK-A RECURSIVE METHOD

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Journal of Systems science & Complexity 2009年第2期22卷 303-312页

作者： Chuanyi LUO Yinghui TANG Cailiang LI Department of Economic mathematics Southwestern University of Finance and Economics Chengdu 610074China. School of mathematics and Software science Sichuan Normal University Chengdu 610066 China. Department of information and Computer science Chengdu Electron-Mechanical College Chengdu 610031China.

This paper considers the Geom/G/1 queueing model with feedback according to a late arrival system with delayed access （LASDA）. Using recursive method, this paper studies the transient property of the queue size from the initial state N（0＋） = i. Some new results about the recursive expression of the transient queue size distribution at any epoch n＋ and the recursive formulae of the equilibrium distribution are obtained. Furthermore, the recursive formulae of the equilibrium queue size distribution at epoch n-, and n are obtained, too. The important relations between stationary queue size distributions at different epochs are discovered （being different from the relations given in M/G/I queueing system）. The model discussed in this paper can be widely applied in all kinds of communications and computer network.

关键词： Discrete time queue equilibrium distribution feedback recursive expression transient distribution.

Landscape Change and its effect on the environment of Daqing City

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Progress in Natural science:Materials International 2005年第7期15卷 641-649页

作者： ZANG Shuying, ZHANG Jing and JIA Li ( college of Life and Environment science, Harbin normal university, Harbin 150080, china college of Resources Environment & Tourism, Capital normal university, Beijing 100037, china college of Economics and Management, Northeast Agricultural university, Harbin 150030, china) college of Life and Environment science Harbin Normal University Harbin 150080 China college of Resources Environment and Tourism Capital Normal University Beijing 100037 China college of Economics and Management Northeast Agricultural University Harbin 150030 China

In this paper, we will study the temporal-spatial landscape change from 1978 to 2001 in Daqing City, based on the mul- ti spectral scanner (MSS) and thematic mapper (TM) images of remote sensing (RS) of 1978, 1988, 1992, 1996 and 2001. In order to explain the effects of the component change on the whole landscape, we make a statistic analysis about the transfer probability matrix of the component types of the landscape by using the ARCGIS platform through the overlay analysis of different landscape components. Based on the transfer probability matrix, we calculate the in-transfer ratio, the out-transfer ratio and the contributor ratio of the special transfer process of the main landscape components. The results illustrate that the cultivated-land, grassland, swamp, and alkaline land are the main contributors resulting in the landscape change: the out-transfer ratios of grassland and swamp are much higher than the in-transfer ones; the in-transfer ratio of alkaline land is much higher than the out-transfer one; the in-transfer ratio of the land-lot is always higher than its out-transfer with the highest rate per year, although there is a small difference among the in-transfers and the out-transfers per year. The main landscape changing processes are the salination of cultivated-land, salination or desertification of grassland, salination and degeneration of swamp. Results in this paper can provide scientific basis for investigating the landscape change mechanism of resources-based city.

关键词： landscape change environmental effect transfer probability resources-based city.

A new smoothing scheme for mathematical programs with complementarity constraints

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science china mathematics 2010年第7期53卷 1881-1890页

作者： YAN TaoDepartment of information and Computational sciences, college of science, Nanjing university of science and Technology, Nanjing 210094, china Department of information and Computational sciences College of Science Nanjing University of Science and Technology Nanjing China

In this paper, we consider a mathematical program with complementarity constraints (MPCC). We present a new smoothing scheme for this problem, which makes the primal structure of the complementarity part unchanged mostly. For the new smoothing problem, we show that the linear independence constraint qualification (LICQ) holds under some conditions. We also analyze the convergence behavior of the smoothing problem, and get some sufficient conditions such that an accumulation point of stationary points of the smoothing problems is C (M, B)-stationarity respectively. Based on the smoothing problem, we establish an algorithm to solve the primal MPCC problem. Some numerical experiments are given in the paper.

关键词： mathematical program with complementarity constrains MPEC-LICQ B-stationarity C-stationarity M-stationarity

Predictor-corrector interior-point algorithm for linearly constrained convex programming

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Journal of Central South university 2001年第3期13卷 208-212页

作者： LIANG Xi-ming (college of information science & Engineering, Central South university, Changsh a 410083, china) college of information science & Engineering Central South University Changsha China

Active set method and gradient projection method are curre nt ly the main approaches for linearly constrained convex programming. Interior-po int method is one of the most effective choices for linear programming. In the p aper a predictor-corrector interior-point algorithm for linearly constrained c onvex programming under the predictor-corrector motivation was proposed. In eac h iteration, the algorithm first performs a predictor-step to reduce the dualit y gap and then a corrector-step to keep the points close to the central traject ory. Computations in the algorithm only require that the initial iterate be nonn egative while feasibility or strict feasibility is not required. It is proved th at the algorithm is equivalent to a level-1 perturbed composite Newton method. Numerical experiments on twenty-six standard test problems are made. The result s show that the proposed algorithm is stable and robust.

关键词： linearly constrained convex programming predictor corrector interior point algorithm numerical experiment

Synthesis and characterization of a strong-fluorescent Eu-containing hydrotalcite-like compound

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science china Chemistry 2010年第6期53卷 1273-1280页

作者： CHEN Hong & ZHANG WenGong Institute of Polymer science,college of Chemistry and Materials science,Fujian normal university,Fuzhou 350007,china Institute of Polymer science College of Chemistry and Materials Science Fujian Normal University Fuzhou China

A novel strong-fluorescent Eu-containing hydrotalcite-like compound (Eu-HTlc) was synthesized using the coprecipitation method,in which aluminum(III) was partially substituted by Europium (III) in the hydrotalcite-like layers,and thenoyltrifluoroacetone,1,10-phenanthroline were dispersed into the anions in the interlayer *** sample was characterized by XRD,XPS,FT-IR,ICP,TG-DSC,TEM and fluorescence spectra,and its composition and structure were *** results indicated that the sample exhibited a characteristic red light (614 nm).The fluorescent lifetime and fluorescence quantum yield of Eu-HTlc were measured to be respectively 893 -s and 66.44%,higher than those of Eu(III)-thenoyltrifluoroacetone1,10-phenanthroline complex [Eu(TTA)3phen].The result of TG-DSC measurement showed the enhanced thermal stability of Eu-HTlc compared with that of MgAl-LDHs and Eu(TTA)*** excellent photoluminescent property and thermal stability,low contents of rare earth ions and ligands,the Eu-HTlc may become one of the novel fluorescent materials with potential applications.

关键词： hydrotalcite-like compound Europium fluorescence intercalation supramolecule

A NEW DESCENT MEMORY GRADIENT METHOD AND ITS GLOBAL CONVERGENCE

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Journal of Systems science & Complexity 2011年第4期24卷 784-794页

作者： Min SUN Qingguo BAI Department of MaShematics and information science Zaozhuan9 University Zaozhuang 277160 China. School of Management Qufu Normal University Rizhao 276826 China

In this article, a new descent memory gradient method without restarts is proposed for solving large scale unconstrained optimization problems. The method has the following attractive properties： 1） The search direction is always a sufficiently descent direction at every iteration without the line search used; 2） The search direction always satisfies the angle property, which is independent of the convexity of the objective function. Under mild conditions, the authors prove that the proposed method has global convergence, and its convergence rate is also investigated. The numerical results show that the new descent memory method is efficient for the given test problems.

关键词： Global convergence memory gradient method sufficiently descent.

On 3-colorability of planar graphs without adjacent short cycles

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science china mathematics 2010年第4期53卷 1129-1132页

作者： WANG YingQian 1,MAO XiangHua 1,LU HuaJing 2 & WANG WeiFan 1 1 college of mathematics,Physics and information Engineering,Zhejiang normal university,Jinhua 321004,china 2 college of Basic science,Ningbo Dahongying university,Ningbo 315175,china college of mathematics Physics and Information Engineering Zhejiang Normal University Jinhua China college of Basic science Ningbo Dahongying University Ningbo China

A short cycle means a cycle of length at most *** this paper,we prove that planar graphs without adjacent short cycles are *** improves a result of Borodin et al.(2005).

关键词： planar graph coloring extension cycle

Weighted composition operators between μ-Bloch spaces on the unit ball

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science china mathematics 2005年第10期48卷 1349-1368页

作者： ZHANG Xuejun~1 & XIAO Jianbin~2 1. college of mathematics and Computer science,Hunan normal university,Changsha 410006,china(email:xuejunttt@263. net) 2. The School of science,Hangzhou Dianzi university,Hangzhou 310037,china college of mathematics and Computer science Hunan Normal University Changsha China The School of science Hangzhou Dianzi University Hangzhou China

In this paper,necessary and sufficient conditions are given for the weighted composition operator T_(ψ,ψ) to be bounded or compact from the space β_μ to β_ν (or β_(μ,0) to β_(ν,0) ) on the unit ball of C^***... 详细信息

关键词： μ-Bloch space, weighted composition operator, boundedness, compactness.