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Strong uniqueness of best approximations in spaces of bounded linear operators

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Science china Mathematics 2004年第3期47卷 339-351页

作者： LI Chong HE Jinsu department of Mathematics, zhejiang {2. Hangzhou 31002., china department of Mathematics, zhejiang normal university jinhua 3.1004, china 1. department of Mathematics Zhejiang University 310027 Hangzhou China 2. department of Mathematics Zhejiang Normal University 321004 Jinhua China

The present paper is concerned with problems of the strong uniqueness of the best approximation and the characterization of a uniqueness element in operator *** results on the strong uniqueness of the best approximation operatorfrom RS-sets are proved and the uniqueness element of a sun in the compactoperator space from c0 to c0 is characterized by the strict Kolmogorov's *** recent results due to Lewicki and others are extended and improved.

关键词： best approximation operator, RS-set, sun, strong uniqueness, uniqueness element.

A lower bound on the total signed domination numbers of graphs

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Science china Mathematics 2007年第8期50卷 1157-1162页

作者： Xin-zhong LU department of Mathematics,zhejiang {2. university,jinhua 3.1004,china department of Mathematics Zhejiang Normal University Jinhua 321004 China

Let G be a finite connected simple graph with a vertex set V (G) and an edge set E(G). A total signed domination function of G is a function f : V (G) ∪ E(G) → {?1, 1}. The weight of f is w(f) = Σ x∈V(G)∪E(G) f(x). For an element x ∈ V (G) ∪ E(G), we define $f[x] = \sum\nolimits_{y \in N_T [x]} {f(y)} $ . A total signed domination function of G is a function f : V (G) ∪ E(G) → {?1, 1} such that f[x] ? 1 for all x ∈ V (G) ∪ E(G). The total signed domination number γ s * (G) of G is the minimum weight of a total signed domination function on G.In this paper, we obtain some lower bounds for the total signed domination number of a graph G and compute the exact values of γ s * (G) when G is C n and P n .

关键词： total signed domination function total signed domination number 2.A33

Schwarz-Pick estimates for positive real part holomorphic functions on unit ball and polydisc

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Science china Mathematics 2010年第4期53卷 1017-1024页

作者： LIU Yang 1,& CHEN ZhiHua 2.1 department of Mathematics,zhejiang {2. university,jinhua 3.1004,china 2.department of Mathematics,Tongji university,Shanghai 2.0092.china 1. department of Mathematics Zhejiang Normal University Jinhua 321004 China2. Department of Mathematics Tongji University Shanghai 200092 China

We give higher order derivatives Schwarz-Pick estimates for all positive real part holomorphic functions on Bn and D n,and generalize early work on Schwarz-Pick estimate of higher order derivatives for holomorphic fun... 详细信息

关键词： Schwarz-Pick estimate holomorphic function Taylor expansion

Application test of matter element analysis in earthquake forecast

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Acta Seismologica Sinica(English Edition) 1998年第6期11卷 89-94页

作者： LI HUA FENG department of geography,{2., jinhua 3.1004, china 1. department of geography Zhejiang Normal University 321004 Jinhua China

Calculation by means of the previous indices of the seismic activity can have the matter element analysis possess the forecast function. Readjusting repeatedly the grade limit value of every index can maximize the historical fitting ratio of the calculated and actual grade of the annual maximum magnitude, whose result is relatively ideal.

关键词： correlation function matter element analysis annual maximum magnitude earthquake forecast

Bifurcations of travelling wave solutions for two generalized Boussinesq systems

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Science china Mathematics 2008年第9期51卷 1577-1592页

作者： LI JiBin1,2.1 department of Mathematics, zhejiang normal university,{2., china 2.department of Mathematics, Kunming university of Science and Technology, Kunming 650093, china department of Mathematics Zhejiang Normal University Jinhua 321004 China department of Mathematics Kunming University of Science and Technology Kunming 650093 China

Using the methods of dynamical systems for two generalized Boussinesq systems, the existence of all possible solitary wave solutions and many uncountably infinite periodic wave solutions is obtained. Exact explicit parametric representations of the travelling solutions are given. To guarantee the existence of the above solutions, all parameter conditions are determined.

关键词： nonlinear wave bifurcation solitary wave exact explicit solution generalized Boussinesq system 34C37 34C2. 74J30 58Z05

Study on sea water intrusion into palaeochannels on south coastal plain of the Laizhou Bay by the Bohai Sea

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Acta Oceanologica Sinica 2003年第1期22卷 69-74页

作者： Han Mei geography department, Shandong {2. university, Jinan 2.0014, china Shandong normal Univ Dept Geog Jinan 250014 Peoples R China

The palaeochannel evolution in the study region is divided into four stages by such methods as 14C dating. Sea water intrusion through palaeochannels has been studied as a focal point. Palaeochannels are the main passageways through which the sea water intrudes at a higher speed, through many means and in a changeable dynamic state.

关键词： Palaeochannel sea water intrusion south coastal plain of Laizhou Bay

Different-Periodic Travelling Wave Solutions for Nonlinear Equations

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Communications in Theoretical Physics 2004年第4期41卷 481-486页

作者： YE Li-Jun~1 LIN Ji~(1,2.1 department of Physics,zhejiang {2. university,jinhua 3.1004,china2.Physics department,Shanghai Jiao Tong university,Shanghai 2.0030,china Physics department Shanghai Jiao Tong University Shanghai 200030 China

Using Jacobi elliptic function linear superposition approach for the(1+1)-dimensional Caudrey-Dodd-Gibbon-Sawada-Kotera(CDGSK)equation and the(2.1)-dimensional Nizhnik-Novikov-Veselov(NNV)equation,many new periodic travelling wave solutions with different periods and velocities are obtained based on the knownperiodic *** procedure is crucially dependent on a sequence of cyclic identities involving Jacobi ellipticfunctions sn(ξ,m),cn(ξ,m),and dn(ξ,m).

关键词： linear superposition nonlinear equation travelling wave solution

Codimension 3 nonresonant bifurcations of homoclinic orbits with two inclination flips

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Science china Mathematics 2005年第2期48卷 248-260页

作者： SHUI Shuliang & ZHU Deming College of Mathematics and Physics, zhejiang normal university, jinhua 3.1004,{2. department of Mathematics, East{2. normal university, Shanghai 2.0062.{2. 1. College of Mathematics and Physics Zhejiang Normal University 321004 Jinhua China 2. department of Mathematics East China Normal University 200062 Shanghai China

Homoclinic bifurcations in four-dimensional vector fields are investigated by setting up a local coordinate near a homoclinic orbit. This homoclinic orbit is principal but its stable and unstable foliations take inclination flip. The existence, nonexistence, and uniqueness of the 1-homoclinic orbit and 1-periodic orbit are studied. The existence of the two-fold 1-periodic orbit and three-fold 1 -periodic orbit are also obtained. It is indicated that the number of periodic orbits bifurcated from this kind of homoclinic orbits depends heavily on the strength of the inclination flip.

关键词： bifurcation, homoclinic orbit, non-resonance, inclination flip, 1-periodic orbit.

Variable Separation Solution for(1+1)-Dimensional Nonlinear Models Related to Schrdinger Equation

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Communications in Theoretical Physics 2004年第10期42卷 568-572页

作者： XU Chang-Zhi~(1,2. ZHANG Jie-Fang~11 Institute of Nonlinear Physics,zhejiang normal {2.,jinhua 3.1004,china2.department of Physics and Mathematics,jinhua Educational College,jinhua 32.000,china department of Physics and Mathematics Jinhua Educational College Jinhua 321000 China

A variable separation approach is proposed and successfully extended to the(1+1)-dimensional *** new exact solution of(1+1)-dimensional nonlinear models related to Schr(?)dinger equation by the entranceof three arbitrary functions is *** special types of soliton wave solutions such as multi-soliton wave solution,non-stable soliton solution,oscillating soliton solution,and periodic soliton solutions are discussed by selecting thearbitrary functions appropriately.

关键词： variable separation approach (1+1)-dimensional nonlinear models solution of soliton