Table of Content

25 March 1990, Volume 10 Issue 1 Previous Issue    Next Issue

For Selected:

View Abstracts

Download Citations EndNote Reference Manager ProCite BibTeX RefWorks

Toggle Thumbnails

Articles

Select

BIFURCATION PROBLEMS OF MULTIPARAMETER AND MULTIBRANCH AND THEIR APPLICATIONS Zhang Chengdian, Li Kaitai Acta mathematica scientia,Series B. 1990, 10 (1):  1-19.  Abstract ( 38 )   RICH HTML PDF (1175KB) ( 29 )   Save This paper deals with the bifurcation problems of multiparameter and multibranch and their approximations. It derives general approximation results of solution branches in the neighbourhood of a singular (limit, turning or multibranch) point, and shows that turning and multibranch points are bifurcation points. The abstract theories are applied to a mixed finite element approximation of stationary Navier-Stokes equation. Related Articles | Metrics

Select

GENERAL VARYING LAW OF THE LARGEST VELOCITY OF STEP-ROCKETS Zhu Miaolong, Guang Yu Acta mathematica scientia,Series B. 1990, 10 (1):  21-33.  Abstract ( 39 )   RICH HTML PDF (682KB) ( 32 )   Save In this paper, we shall propose a method to solve the problem for the varying law of the largest velocity of step-roekets. Related Articles | Metrics

Select

A SUMMATION FORMULA FOR PRODUCTS OF ELECTRON RADIAL WAVE FUNCTION IN CONSTANT MAGNETIC FIELD Song Yu Acta mathematica scientia,Series B. 1990, 10 (1):  35-37.  Abstract ( 36 )   RICH HTML PDF (167KB) ( 34 )   Save This paper generalizes the formula sum from ∑n Ins(v)Ins'(v)=δss' to the case with two different v. Ins(v) is the radial wave function of an electron in a constant magnetic field. These results are very useful in synchroton radiation and astrophysics. Related Articles | Metrics

Select

CONVERGENCE OF THE APPROXIMATE SOLUTIONS TO ISENTROPIC GAS DYNAMICS Chen Guiqiang, Lu Yunguang Acta mathematica scientia,Series B. 1990, 10 (1):  39-45.  Abstract ( 38 )   RICH HTML PDF (370KB) ( 27 )   Save This paper gives four pairs of entropies (ηi, qi) (i=1, 2, 3, 4) to the isentropic gas dynamics equations ρt+(ρu)x=0 (ρu)t+(ρu2+p(ρ))x=0 p(ρ)=k2ργ,1 < γ < 3. when all the function equations are satisfied <v,ηiqj-ηjqi>=<v,ηi><v,qj>-<v,ηj><v,qi>. where supp v is small,v is a Dirac mass under a strong confine ρ ≥ C(T) > 0. Related Articles | Metrics

Select

D'ALEMBERT FORMULA AND THE DIRECT OR INVERSE PROBLEMS FOR WAVE EQUATION Liu Ruxun Acta mathematica scientia,Series B. 1990, 10 (1):  47-56.  Abstract ( 46 )   RICH HTML PDF (542KB) ( 25 )   Save In this paper, a new proof of D'Alembert formula for Cauchy problems of wave equation is proposed. And some D'Alembert-type formulas for Cauchy problem with discontinuous coefficients on semi-infinite initial boundary value problem are proposed. Based on above discussion, the characteristics methods for the direct and inverse problems of the stress wave equation for uniform layerad elastic medium are investigated. The aim of this paper is to stress the significance and application of the characteristics concept and approach. Related Articles | Metrics

Select

THE SOLVABILITY OF SEMI-ADMISSIBLE ABSTRACT BOUNDARY VALUE PROBLEM Lei Peng, Yang Mingzhu Acta mathematica scientia,Series B. 1990, 10 (1):  57-62.  Abstract ( 41 )   RICH HTML PDF (403KB) ( 27 )   Save In this paper some results in operator theory and integro-differential equations are extended to some semi-admissible cases. Related Articles | Metrics

Select

EXISTENDED SECOND DERIVATIVE METHODS FOR SOLVING STIFF SYSTEMS OF ODEs Xu Xuhai Acta mathematica scientia,Series B. 1990, 10 (1):  63-69.  Abstract ( 44 )   RICH HTML PDF (409KB) ( 25 )   Save In this paper a class of the extended second derivative formulas is presented. Based on the extended k-step second derivative formula a new predictor-corrector method called Extended k-step second Derivative Method for stiff systems is formulated with the k-step second derivative formula as its implicit predictor. The extended second derivative methods have the higher orders and the better stability properties. The computational effort is comparitively large, but much of it can be saved, so that the methods are acceptable and efficient. Related Articles | Metrics

Select

THE FIRST BOUNDARY VALUE PROBLEM FOR STRONGLY DEGENERATE QUASILINEAR PARABOLIC EQUATIONS Chen Zuchi Acta mathematica scientia,Series B. 1990, 10 (1):  71-78.  Abstract ( 60 )   RICH HTML PDF (1050KB) ( 28 )   Save This paper concerns with existence of generalized solutions of first boundary value problem for a kind of strongly degenerate quasilinear parabolic equations. The author assumes that the coefficients in the equation satisfy strongly degenerate monotone condition and other weakened conditions comparing with those of Ladyzenskaja's. An existence theorem is given and proved. Related Articles | Metrics

Select

COHOMOLOGY THEORY OF DIFFERENTIAL OPERATORS Wang Jichun Acta mathematica scientia,Series B. 1990, 10 (1):  79-84.  Abstract ( 37 )   RICH HTML PDF (1231KB) ( 25 )   Save In this paper, we propose the concept of cohomological operator. Concretely, we suggest the cohomological differential operator, correlative cohomological differential operator and extensive cohomological differential operator and bring covariant derivative into the extensive cohomological differential operator, We construct one type of nonlinear differential equations by extensive cohomological differential operator and compare the obtained resales with the Yang-Mills equation[1,2,3]. Related Articles | Metrics

Select

SUPERLINEAR CONSERVATION LAW WITH VISCOSITY Ding Xiaxi, Luo Peizhu, Yan Guozheng Acta mathematica scientia,Series B. 1990, 10 (1):  85-99.  Abstract ( 45 )   RICH HTML PDF (4010KB) ( 35 )   Save This paper gives some global existence results of the superlinear conservation law with viscosity. Related Articles | Metrics

Select

ON A REACTION DIFFUSION SYSTEM OF COMPETING PREDATORS Yang Zhiping Acta mathematica scientia,Series B. 1990, 10 (1):  101-110.  Abstract ( 40 )   RICH HTML PDF (977KB) ( 22 )   Save This paper is concerned with the existence-uniqueness and the asymptotic behavior of the solution of a coupled system of reaction diffusion equations which arose from biochemistry. Under Diricblet boundary condition, the existence and the bifurcation of nonegative steady-state solutions of the system will be studied. The principal methods used in this paper are the monotone method and the topological degree method. Related Articles | Metrics

Select

RECURRENCE FOR THE GENERALIZED BIRTH-DEATH CHAINS IN A RANDOM ENVIRONMENT Ding Wanding Acta mathematica scientia,Series B. 1990, 10 (1):  111-120.  Abstract ( 49 )   RICH HTML PDF (1794KB) ( 27 )   Save This is a study of one dimensional generalized birth-death chains in a random environment (GBDIRE). We give two sufficient conditions of recurrence for GBDIRE. Related Articles | Metrics