共查询到20条相似文献,搜索用时 15 毫秒
1.
APRIORIESTIMATESTOTHEMAXIMUMMODULUSOFGENERALIZEDSOLUTIONSOFACLASSOFQUASILINEARELLIPTICEQUATIONSWITHANISOTROPICGROWTHCONDITION... 相似文献
2.
成祥生 《应用数学和力学(英文版)》1985,6(3):233-240
This paper discusses the forced vibrations of the elastic shallow shell due to the moving mass by means of the variational method. In the text mentioned above a series of problems such as the forced vibrations, resonance conditions and critical speed and so forth. 相似文献
3.
LetGbeaboundeddomaininthen-dimensionEuclideanspaceE\",I
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4.
The existence and uniqueness of solutions to backward stochastic differential equations with jumps and with unbounded stopping time as terminal under the non-Lipschitz condition are obtained. The convergence of solutions and the continuous dependence of solutions on parameters are also derived. Then the probabilistic interpretation of solutions to some kinds of quasi-linear elliptic type integro-differential equations is obtained. Foundation item: the National Natural Science Foundation of China (79790130); the Foundation of Zhongshan University Front Research Biography: Situ Rong (1935 −) 相似文献
5.
IntroductionInRef.[1 ] ,theauthorsestablishedtheuniqueexistenceofthesmoothsolutionforthefollowingcouplednonlinearequationsut=uxxx+buux+ 2vvx, (1 )vt=2 (uv) x. (2 )Thesewereproposedtodescribetheinteractionprocessofinternallongwaves.InRef.[2 ] ,ItoM .proposedarecursionoperatorbywhichheinferredthatEqs.(1 )and (2 )possesinfinitelymanysymmetriesandconstantsofmotion .InRef.[3 ] ,P .F .HeestablishedtheexistenceofasmoothsolutiontothesystemofcouplednonlinearKdVequation[4 ]ut=a(uxxx+buux) + 2bvvx,(… 相似文献
6.
We present and analyse a new mixed finite element method for the generalized Stokes problem. The approach, which is a natural extension of a previous procedure applied to quasi‐Newtonian Stokes flows, is based on the introduction of the flux and the tensor gradient of the velocity as further unknowns. This yields a two‐fold saddle point operator equation as the resulting variational formulation. Then, applying a slight generalization of the well known Babu?ka–Brezzi theory, we prove that the continuous and discrete formulations are well posed, and derive the associated a priori error analysis. In particular, the finite element subspaces providing stability coincide with those employed for the usual Stokes flows except for one of them that needs to be suitably enriched. We also develop an a posteriori error estimate (based on local problems) and propose the associated adaptive algorithm to compute the finite element solutions. Several numerical results illustrate the performance of the method and its capability to localize boundary layers, inner layers, and singularities. Copyright © 2005 John Wiley & Sons, Ltd. 相似文献
7.
顾卫华 《应用数学和力学(英文版)》1985,6(12):1205-1215
The formula of BEM suited to solve the problems of wave propagation in boundlessmedium is obtained from numerical treatment of Kirchhoff integral equation.Afer quotingthe coefficients of refraction and reflection of wave at surface or interface,the expression ofBEM which is suitable for the problems of wave propagation in multi-isotropic mediums isalso given. 相似文献
8.
The following initial-boundary value problem for the systems with multidimensional inhomogeneous generalized Benjamin-Bona-Mahony ( GBBM ) equations is reviewed. The existence of global attractors of this problem was proved by means of a uniform priori estimate for time. 相似文献
9.
The long time behavior of solution of the Hasegawa-Mima equation with dissipation term was considered. The global attractor problem of the Hasegawa-Mima equation with initial periodic boundary condition was studied. Applying the uniform a priori estimates method, the existence of global attractor of this problem was proved, and also the dimensions of the global attractor was estimated. 相似文献
10.
It’swell_knownthatthesolutionsofbackwardstochasticdifferentialequations(BSDEs)playanimportantroleinthefinancialmarket(SeeRef.[1]).WithunboundedstoppingtimesτasterminalsundertheLipschitzconditionsandconditionthatterminalssatisfyE|ξ|2eK(τ∧T)≤c0<∞,0≤T<∞orξ=0,Refs… 相似文献
11.
Hui-Qin Lu 《Discrete and continuous dynamical systems》2024,29(4):1961-1971
We consider a generalized anisotropic curvature flow involving a positive power $ alpha $ of the curvature: $ V = A({bf n})H^{alpha} $ in a band domain $ Omega: = [-1,1]times mathbb{R}, $ where $ A $ is a smooth positive function, $ V, {bf n} $ and $ H $ denote the normal velocity, the unit normal vector and the curvature of a simple plane curve $ gamma_{t} $, respectively. In addition, we assume that $ gamma_{t} $ contacts $ partial_{pm}Omega $ with slopes equaling to $ pm k(t) $ for some bounded function $ k $. We first give the a priori $ C^2 $ estimates (including the uniform bound of $ H $, which plays a key role in the parabolicity of the equation) and show the time-global existence for the initial-boundary value problem. Then we construct an entire solution of the problem by renormalization method, and show that the entire solution propagates from $ -infty $ to $ +infty $, connecting two traveling waves at $ t = -infty $ and $ t = +infty $ in case $ k(t) $ tends to two positive constants as $ trightarrow mpinfty $. 相似文献
12.
In this paper,we study the initial-boundary value problem of one class of nonlinear Schr(o)dinger equations described in molecular crystals.Furthermore,the existence of the global solution is obtained by means of interpolation inequality and a priori estimation. 相似文献
13.
In this paper, we study the initiial-boundary value problem of one class of nonlinear Schrodinger equations described in molecular crystals. Furthermore, the existence of the global solution is obtained by means of interpolation inequality and a priori estimation. 相似文献
14.
C. B. Clemons 《Journal of Dynamics and Differential Equations》1997,9(1):53-65
The purpose is to extend the existence result of vortex solutions to semilinear elliptic equations for a large class of nonlinearities. M. I. Weinstein used variational techniques to show the existence of nodal solutions for the specific nonlinear term f(¦¦)=(1–¦¦2). An ordinary differential equation phase space setting is used to show the unique transverse intersection of unstable and stable manifolds which contain the solutions satisfying the necessary boundary conditions under certain assumptions on the nonlinearity. 相似文献
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By the degree theory on positive cone together with the technique of a priori estimate, the nontrivial equilibrium solutions of a strong nonlinearity and weak coupling reaction diffusion system and the structure of the equilibrium solutions are discussed. 相似文献
17.
For the most part, analytical solutions for steady unsaturated infiltration have been restricted to infinite and semi-infinite seepage geometries, using the quasi-linear approximation for the hydraulic conductivity. We provide analytical series methods to solve the steady quasi-linear flow equations, in finite irregular seepage geometries. Unlike the classical approach, the series method has been modified, to cater for arbitrary boundary geometry and surface recharge distributions. The matrix flux potential and the stream function both satisfy the same governing partial differential equation, and the stream function formulation is used to estimate the series coefficients. For a finite vadose zone, the stream function solution does not uniquely determine the matrix flux potential, when flux boundary conditions are used. Consequently, the stream function solution applies to a range of moisture distributions, for given infiltration and evapotranspiration rates through the surface. 相似文献
18.
Guo Lin ;Yahui Wang 《Discrete and continuous dynamical systems》2023,28(2):984-998
This article studies the propagation threshold in a competitive system without the classical comparison principle, which models the invasion-coexistence process between two competitors of which one is the invader and another is the aborigine. We obtain a linearly determined threshold that is the spreading speed of the invader in initial value problems. To estimate the spreading speed, we construct several auxiliary scalar equations and use the method of generalized upper solutions. In population dynamics, our results imply that even in a nonmonotone competitive system, the invader may invade the habitat of the aborigine at an almost constant speed and two species could coexist eventually. 相似文献
19.
In this paper we consider the regularity criteria for weak solutions to the 3D MHD equations. It is proved that under the condition b being in the Serrin's regularity class, if the pressure p belongs to Lα,γ with or the gradient field of pressure p belongs to Lα,γ with on [0,T], then the solution remains smooth on [0,T]. 相似文献
20.
When multicollinearity is present in a set of the regression variables,the leastsquare estimate of the regression coefficient tends to be unstable and it may lead toerroneous inference.In this paper,generalized ridge estimateβ(K)of the regression coefficientβ=vec(B)is considered in multivaiate linear regression model.The MSE of the aboveestimate is less than the MSE of the least square estimate by choosing the ridgeparameter matrix K.Moreover,it is pointed out that the Criterion MSE for choosingmatrix K of generalized ridge estimate has several weaknesses.In order to overcomethese weaknesses,a new family of criteria Q(c)is adpoted which includes the criterionMSE and criterion LS as its special case.The good properties of the criteria Q(c)areproved and discussed from theoretical point of view.The statistical meaning of thescale c is explained and the methods of determining c are also given. 相似文献