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1.
Thetheoryofharmonicmapsintoacompactnonpositivelycurvedtargetiswell-developed.TheexistenceofsuchaharmonicmappinginanygivenhomotopyclassisestablishedbyEellsandSampson[1]in1964,andlater,in1967,Hartman[2]gaveaproofoftheuniqueness.Thispaperisdevotedtoanapplicationo… 相似文献
2.
§ 1.Introduction LetBnbetheunitballinCn,anddvthenormalizedLebesguemeasureonBn.SobolevspaceL2 ,1isthespaceoffunctionsu :Bn→C ,forwhichthenorm‖u‖1/ 2 =∑ni=1 ∫Bn u zi(z) 2 + u zi(z) 2 dν1/ 2 <∞ .L2 ,1/ 2 isaHilbertspacewiththeinnerproduct〈u ,v〉1/ 2 =∑ni=1〈 u zi, u zi〉L2 (dν) +∑ni=1〈 u zi, u … 相似文献
3.
LetB ={0 ,1 }betheusualbinaryBooleanalgebra .ThematricesoverBarecalledBooleanmatrices.Ann×nBooleanmatrixAiscalledaprimitivematrixifthereexistsapositiveintegerksuchthatAk=J (whereJistheuniversalmatrix) .TheleastsuchkiscalledtheexponentofA ,denotedbyγ(A) . In proj… 相似文献
4.
§ 1 IntroductionInthispaper ,wewillconsiderthesemilinearSchr dingerequationinonespacedimensionofthetypeut-iuxx =F(u) . (x ,t)∈R×R+,( 1 )u(x ,0 ) =u0 , x ∈R ,( 2 )whereu =u(x ,t)iscomplex valuedfunction ,andFisasmoothfunctionofusuchthat|F(u) | =O( |u|α+1)for |u|sufficientlysmalland… 相似文献
5.
1 IntroductionInthepaper,weconsiderthefollowingK -Sequation (forexample,see [1 ] -[3]andreferencestherein)inspacedimension≥ 3:Δ2 u+Δu+ 12 | u|2 -12 Ni=1li∫IN| u|2 dx=0 ,x∈IN,(1 )withL periodicboundaryconditions,L =(l1,l2 ,… ,lN)beingthesizeofatypicalpatterncell (alsobifurcationpar… 相似文献
6.
§ 1.ProblemandAssumptions Thispaperdealswiththesolutionsofthefollowingdifferentialinclusionproblem :Au∈f(x,u) ,x∈Ω ;u=0 ,x∈ Ω ,(1 )whereAu(x) =-∑Ni=1Di[ai(x ,Du(x) ) ] ,Ω RNisaboundeddomainwithpiecewiseLipschitzboundary Ω ,Du =(D1u ,D2 u ,… ,DNu) ,Diu = u xi,i=1 ,2 ,… ,N ,andf:Ω×R→ 2 Risa… 相似文献
7.
§ 1.Introduction Inthispaperwestudythestrongandweakpropertyoftravellingwavefrontsolutions (TWFS)forthefollowingdegenerateparabolicequation : ψ(u) t = 2 u x2 +f(u) . ( 1 .1 ) Welookforsolutionsof( 1 .1 )oftheformu(x,t) =q(x -ct) (cisthewavespeed) ,whereq( ξ) ,ξ=x -ct,asafunctionofas… 相似文献
8.
§ 1.Introduction LetRbearingwithidentityandMaleftR module .AleftR moduleUiscalledM injectiveif,foreverysubmoduleNofMandeveryhomomorphism :N→U ,canbeextendedtoahomomorphism ψ :M→U .AleftR moduleMiscalledaV modulebyRamamurthi[1]andTominaga[2 ](andiscalledaco semis… 相似文献
9.
SOME EXTENSIONS OF PALEY-WIENNER THEOREM 总被引:1,自引:0,他引:1
§1.IntroductionandMotivationTheclasicalShannon’ssamplingtheoremholdsduetothefolowingtworeasons:(i)q(t,u)=sinπ(t-u)π(t-u)isthe... 相似文献
10.
张吉慧 《高校应用数学学报(英文版)》2003,18(1):45-52
§ 1 IntroductionWeconsiderthefourthordersemilinearsubellipticboundaryvalueproblemΔ2 Hu +cΔHu =f( (z ,t) ,u) inD ,u|D =ΔHu|D =0 ,( 1 .1 )whereDisaboundedopensubsetoftheHeisenberggroupHnandΔHisthesubellipticLapla cianonHn.WerecallthatHnistheLiegroupwhoseunderlyingmani… 相似文献
11.
ChenXiangying 《高校应用数学学报(英文版)》2001,16(3):251-258
Abstract. The existence and uniqueness of classical global solutions and the nonexistence of global solutions to the first boundary value problem and the second boundary value problem for the equation ua-a1uxx-a2uxxl-a3uxxu=ψ(ux)x are proved 相似文献
12.
By variational methods, for a kind of Yamabe problem whose scalar curvature vanishes in the unit ball BN and on the boundary S^N-1 the mean curvature is prescribed, we construct multi-peak solutions whose maxima are located on the boundary as the parameter tends to 0^+ under certain assumptions. We also obtain the asymptotic behaviors of the solutions. 相似文献
13.
On Eigenvalue Intervals and Eigenfunctions of Nonresonance Singular Dirichlet Boundary Value Problems 总被引:1,自引:0,他引:1
Zhao-cai HaoDepartment of Mathematics Qufu Normal University Qufu China 《应用数学学报(英文版)》2002,18(4):569-578
In this paper we shall consider the nonresonance Dirichlet boundary value problemwhere λ>0 is a parameter, p>0 is a constant. Intervals of A are determined to ensure the existence of a nonnegative solution of the boundary value problem. For λ=1, we shall also offer criteria for the existence of eigenfunctions. The main results include and improve on those of [2,4,6,8]. 相似文献
14.
Cai Di ZHAO Yong Sheng LI Sheng Fan ZHOU 《数学学报(英文版)》2007,23(11):2043-2060
This paper discusses the Cauchy problem of elliptic-elliptic-type Davey-Stewartson systems with zero-order dissipation on R^2. Making use of the Fourier spectral projector, together with a long time comparison between the solutions to the Davey-Stewartson systems and to an auxiliary problem, we prove that the global attractor in H^1 (R^2) for the addressed Davey-Stewartson systems is a compact subset of H^2(R^2), and thus reveal the asymptotic smoothing effect of the solutions for the systems. 相似文献
15.
§ 1 IntroductionIn this paperwe shall study successively the equationsgiven in [1 ,2 ] .Underthe sameconditions(i.e.the initial boundary value and other conditions) as in[1 ,2 ] ,the upperbound of the dimension of their global attractor will be obtained respectively.Theexistence of the global attractors have been proved in[1 ,2 ] .This paper is organized as follows:In§ 2 ,we derive the Frechet differential of the solution operator s(t) for theperturbed system.In§ 3 ,we show the finite di… 相似文献
16.
Hui-ling LI & Ming-xin WANG Department of Mathematics Southeast University Nanjing China 《中国科学A辑(英文版)》2007,50(4):590-608
This paper deals with the properties of positive solutions to a quasilinear parabolic equation with the nonlinear absorption and the boundary flux. The necessary and sufficient conditions on the global existence of solutions are described in terms of different parameters appearing in this problem. Moreover, by a result of Chasseign and Vazquez and the comparison principle, we deduce that the blow-up occurs only on the boundary (?)Ω. In addition, for a bounded Lipschitz domainΩ, we establish the blow-up rate estimates for the positive solution to this problem with a= 0. 相似文献
17.
Xiao-jing Cai Quan-sen Jiu Chun-yan Xue 《应用数学学报(英文版)》2007,23(4):637-650
In this paper,the Dirichlet problem of Stokes approximate of non-homogeneous incompressibleNavier-Stokes equations is studied.It is shown that there exist global weak solutions as well as global andunique strong solution for this problem,under the assumption that initial density ρ_0(x)is bounded away from0 and other appropriate assumptions(see Theorem 1 and Theorem 2).The semi-Galerkin method is applied toconstruct the approximate solutions and a prior estimates are made to elaborate upon the compactness of theapproximate solutions. 相似文献
18.
In this paper we consider a p-Laplacian equation with the homogeneous Dirichlet boundary condition. We establish a blow-up result for certain solution
with positive initial energy.
This work was supported by the National Natural Science Foundation of China 10771032, and the Natural Science Foundation of
Jiangsu province BK2006088. 相似文献
19.
Xiao-hong Qin 《应用数学学报(英文版)》2008,24(3):523-528
In this paper, we investigate the large-time behavior of solutions to the initial-boundary value problem for n × n hyperbolic system of conservation laws with artificial viscosity in the half line (0, ∞). We first show that a boundary layer exists if the corresponding hyperbolic part contains at least one characteristic field with negative propagation speed. We further show that such boundary layer is nonlinearly stable under small initial perturbation. The proofs are given by an elementary energy method. 相似文献
20.
Xiao-nlng Lin Hong Wang Da-qing Jiang 《应用数学学报(英文版)》2007,23(2):289-302
This paper is devoted to the study ofthe existence of single and multiple positive solutions forthe first order boundary value problem x′= f(t,x),x(0)=x(T),where f ∈ C([0,T]×R).In addition,weapply our existence theorems to a class of nonlinear periodic boundary value problems with a singularity at theorigin.Our proofs are based on a fixed point theorem in cones.Our results improve some recent results in theliteratures. 相似文献