共查询到20条相似文献,搜索用时 0 毫秒
1.
Shi Zhongci 《数学年刊B辑(英文版)》1990,11(2):148-155
It is observed in practice that the numerical accuracy of the two unconventional plate elements, i. e., the nine parameter quasi-conforming and generalized conforming elements, is better than that of the usual Zienkiewicz in compatible cubic element and of a new element proposed recently by Specht, although all these elements have the same asymptotical rate of convergence O(h) in the energy norm. In the paper a careful error analysis for the quasi-conforming and generalized conforming elements is given. It is shown that the consistency error due to nonconformity of the two unconventional elements is of order O(h~2), one order high than that of other conventional nonconforming elements with nine parameters. 相似文献
2.
曾宪昌 《数学物理学报(A辑)》1982,(4)
This paper describes the algorithm and concrete process with BASIC program to realize theorem proving and solving some artificial intelligence problem. For theorem proving we introduce "subsumptiontest", "omiting method" and "programing technics" to speed up for finding proofs of theorem as the previous paper. 相似文献
3.
Consider solving an overdetermined system of linear algebraic equations by both the least squares method (LS) and the total least squares method (TLS). Extensive published computational evidence shows that when the original system is consistent. one often obtains more accurate solutions by using the TLS method rather than the LS method. These numerical observations contrast with existing analytic perturbation theories for the LS and TLS methods which show that the upper bounds for the LS solution are always smaller than the corresponding upper bounds for the TLS solutions. In this paper we derive a new upper bound for the TLS solution and indicate when the TLS method can be more accurate than the LS method.Many applied problems in signal processing lead to overdetermined systems of linear equations where the matrix and right hand side are determined by the experimental observations (usually in the form of a lime series). It often happens that as the number of columns of the matrix becomes larger, the ra 相似文献
4.
1IntroductionUnique continuation of solutions to the linear partial di?erential equations with analyticcoe?cients is well known.There are more general results in elliptic,parabolic and hyperbolicequations(cf.[8-10,12-13]and references therein).The continu… 相似文献
5.
唐贤江 《数学物理学报(B辑英文版)》1995,(3)
ONTHEEXISTENCEANDUNIQUENESSOFTHESOLUTIONTOTHENAVIER-STOKESEQUATIONSTangXianjiang(Dept.ofMath.,Sichuanuniversity,Chengdu610064... 相似文献
6.
In this paper, a Liénard equation with a deviating argument has been studied by means of Mawhin's continuation theorem. A new result guaranteeing the existence of periodic solutions is obtained. 相似文献
7.
《Annals of Differential Equations》2008,(1):1-8
In this paper we investigate the global asymptotic stability,boundedness as well as the ultimate boundedness of solutions to a general third order nonlinear differential equation,using complete Lyapunov function. 相似文献
8.
ONTHEABSOLUTESTABILITYOFDIRECTCONTROLSYSTEMSWangJizhong(王继忠)(LinyiTeacher'sCollege,临沂师专,邮编:276005)Abstract:Inthispaper,weinves?.. 相似文献
9.
余桑 《数学物理学报(B辑英文版)》1983,(4)
Einstein's Unified Field Theory (UFT) lacks the elegance and simplicity of General Relativity and Gravitation (GRG) in that latter,he uses purely geometric concepts and, by identifying the objects with appropriate geomtric objects,he finds that the necessary fietd equation are automatically implied in the basic geometric stru- 相似文献
10.
刘彦佩 《应用数学学报(英文版)》1988,(3)
In testing planarity of graphs,there are many criteria.The earliest one as known is the Kuratowski's theorem,then Whitney's,Maclane's, and so forth.Since the early sixties,people have begun researches on algorithms.Up to 1974,Hopcroft and Tarjan found an algorithm with a computing time being a linear function of the order of a graph.This is the linearity concerned here.This paper presents a new approach to the linearity by means of transforming the problem of testing planarity of a graph G into that of finding a spanning tree on another graph H,called an auxiliary graph of G,with the order of H being a linear function of that of G.And moreover,we can also make the size of H be a linear function of that of G.The whole procedure is based on the building up of a theory of linear equations on GF(2)related to G. 相似文献
11.
聂赞坎 《数学物理学报(B辑英文版)》1985,(1)
In this paper the following stochastic integral equation is considered where A is a continuous increasing process, M is a continuous martingale. Mappings φ, F, G map continuous adapted processes into continuous adapted processes. We will prove equation (*) has a unique continuous solution under some conditions. 相似文献
12.
A PL homotopy algorithm is modified to yield a polynomial-time result on its computational complexity.We prove that the cost of locating all zeros of a polynomial of degree n to an accuracy of ε(measured by the number of evaluations of the polynomial)grows no faster than O(max{n~4,n~3log_2(n/ε)}).This work is in response to a question raised in a paper by S.Smale as to the efficiency of piecewise linear methods in solving equations.In comparison with a few results reported,the algorithm under discussion is the only one providing correct multiplicities and the only one employing vector labelling. 相似文献
13.
Huang Zhaobo 《数学年刊B辑(英文版)》1995,16(3):391-398
ONTHECLASSIFICATIONOFAF-ALGEBRASANDTHEIRDIMENSIONGROUPS(Ⅱ)¥HUANGZHAOBOAbstract:Thispaperisacontinuationof[1].Itgivessomeappli... 相似文献
14.
Mo Shaokui 《数学年刊B辑(英文版)》1990,11(1):118-126
Reasoning expressions are those which express the reaasoning procedure by means ofonly deduction rules and the initial formulas(axioms or assumptions)without the helpof any intermediate results.They express the procedure systematically,completely andconcisely.The deduction rules are mappings from formulas(premises)to formula(conclusion).The elementary rules are certain propositional connectives(but notnecessarily truth functions)while the higher rules are certain quantifiers.Besides,thedetachment rule is an inverse of the connective implication,and is itself the kernel ofdeduction method;while another inverse of implication(i.e.the suggestion rule)is thekernel of induction method. 相似文献
15.
Tie Zhang 《计算数学(英文版)》2002,(5)
In this paper, we present a general error analysis framework for the finite volume element (FVE) approximation to the Ritz-Volterra projection, the Sobolev equations and parabolic integro-differential equations. The main idea in our paper is to consider the FVE methods as perturbations of standard finite element methods which enables us to derive the optimal L2 and H1 norm error estimates, and the L∞ and W∞1 norm error estimates by means of the time dependent Green functions. Our disc ussions also include elliptic and parabolic problems as the special cases. 相似文献
16.
Niu Chengying Chen Xiaoxing 《Annals of Differential Equations》2008,(3):306-316
In this paper, we consider almost periodic discrete two-species competitive sys-tems. By using Lyapunov functional, the existence conditions and uniqueness of almost periodic solutions for the this type of systems are obtained. 相似文献
17.
In this paper, we study the algebraic differential and the difference independence between the Riemann zeta function and the Euler gamma function. It is proved that the Riemann zeta function and the Euler gamma function cannot satisfy a class of nontrivial algebraic differential equations and algebraic difference equations. 相似文献
18.
ONEXISTENCE,UNIQUENESSANDREGULARITYOFSTEADYSTATESOLUTIONSTOTHEBASICSEMICONDUCTOREQUATIONSWangYuanming(王元明)FanJishan(樊继山)(Dept... 相似文献
19.
The existence and uniqueness of classical global solutions to a type of Boussinesq equations withinitial and boundary values are studied in this paper. The existence of such solutions is proved bymeans of compactness theorem and Schauders fixed point theorem, and its uniqueness by the so calledenergy method. 相似文献
20.
1. Introduction Let W_∞~((r)) (β) = {f| f∈W_∞~((r)) [-1,1], ||f||_(C[-1,1]) β, ||f~((r))||_∞ 1}.In this paper, we will consider the following Landau problem:λf~((k))(ξ) + μf~((k-1)) (ξ) →inf, f∈W_∞~((r)) (β), (1.1)where ξ∈[-1,1], 1(?)k(?)r-1, and λ, μ real and not all zero, (if k=1,suppose λ≠0 in addition ). A. Pinkus studied it first. To begin with, we introduce some fundamental definitions anddenotions. The perfect spline f, which satisfies || f~((r))||_∞ = 1 andhas n knots and n+r+1 points of equioscillation in [-1,1], isdenoted by x_(nr), which is refered as Tchebyshev perfect spline. And 相似文献