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1.
The motion of the self-gravitational gaseous stars can be described by the Euler-Poisson equations. The main purpose of this article is concerned with the nonlinear stability of gaseous stars in the non-isentropic case, when 34 γ2, S(x,t) is a smooth bounded function. First, we verify that the steady states are minimizers of the energy via concentration-compactness method; then using the variational approach we obtain the stability results of the non-isentropic flow.  相似文献   

2.
In this paper, the uniqueness of stationary solutions with vacuum of Euler-Poisson equations is considered. Through a nonlineax transformation which is a functionof density and entropy the corresponding problem can be reduced to a semilinear ellipticequation with a nonlinear source term consisting of a power function, for which the classical  相似文献   

3.
The motion of the self-gravitational gaseous stars can be described by the Euler-Poisson equations. The main purpose of this paper is concerned with the existence of stationary solutions of Euler-Poisson equations for some velocity fields and entropy functions that solve the conservation of mass and energy. Under different restriction to the strength of velocity field, we get the existence and multiplicity of the stationary solutions of Euler-Poisson system.  相似文献   

4.
The global existence and large time behavior of smooth solutions to multi-dimensional nonisentropic Euler-Poisson equations are established.  相似文献   

5.
董建伟  张又林  程少华 《数学杂志》2015,35(5):1245-1251
本文研究了一维半导体稳态量子能量输运模型的古典解.利用一些不等式技巧证明了当晶格温度充分大且电流密度较小时其解是唯一的,这在文献[3]中没有得到.  相似文献   

6.
Abstract This paper is concerned with the initial-boundary value problem for damped wave equations with a nonlinear convection term in the half space R+{utt-txx+ut+f(u)x=0,t〉0,x∈R+,u(0,x)=u0(x)→u+,asx→+∞,ut(0,x)=u1(x),u(t,0)=ub.For the non-degenerate case f](u+) 〈 0, it is shown in [1] that the above initialboundary value problem admits a unique global solution u(t,x) which converges to the stationary wave φ(x) uniformly in x ∈ R+ as time tends to infinity provided that the initial perturbation and/or the strength of the stationary wave are sufficiently small. Moreover, by using the space-time weighted energy method initiated by Kawashima and Matsumura [2], the convergence rates (including the algebraic convergence rate and the exponential convergence rate) of u(t, x) toward φ(x) are also obtained in [1]. We note, however, that the analysis in [1] relies heavily on the assumption that f'(ub) 〈 0. The main purpose of this paper is devoted to discussing the case of f'(ub)= 0 and we show that similar results still hold for such a case. Our analysis is based on some delicate energy estimates.  相似文献   

7.
In this paper, we are concerned with the following problem:(-△)ku = λf(x)|u|q-2u + g(x)|u|k*-2u, x ∈Ω,u ∈ Hk0(Ω),where Ω is a bounded domain in RNwith N ≥ 2k + 1, 1 q 2, λ 0, f, g are continuous functions on Ω which are somewhere positive but which may change sign on Ω. k* =2N N-2k is the critical Sobolev exponent. By extracting the Palais-Smale sequence in the Nehari manifold, the existence of multiple nontrivial solutions to this equation is verified.  相似文献   

8.
映象方程多解问题的某些研究   总被引:1,自引:0,他引:1  
本文用fp-同伦方法,在一定的技巧和变换的配合下,在紧性条件支持下,研究了赋范线性空间中一类集值映象方程的多解问题。还给出所得理论结果的一个应用。  相似文献   

9.
This article discusses the existence and uniqueness of renormalized solutions for a class of degenerate parabolic equations b(u)t - div(a(u, u)) = H(u)(f + divg).  相似文献   

10.
奇异泛函微分方程边值问题的多重正解   总被引:2,自引:0,他引:2  
通过构造一个特殊的锥,利用逼近方法及不动点指数理论将翁佩萱等[1]关于奇异泛函微分方程边值问题多重正解的工作推广到f(x)关于x=0有奇性的情况。在适当条件下,得到了所考虑的边值问题至少存在两个正解的结论。  相似文献   

11.
1IntroductionIn[1]theexistence0fweaksoluti0ns0fdegeneratequasilinearparabolicinitialboundaryvaluepr0blemonthespaceXT=Lp(O,T;V)hasbeenpr0ved,whereQT=(O,T)xfl,V=W:"(v,fl),whichisaweightedS0b0levspace.Thedegenerati0nisdeterminedbyavectorfunctionv(x)=(v.(x)),IaI=m,withp0sitivec0mponentsv.(x)inflsatisfyingcertainintegrabilityassumptions.Theaim0fthispaperistosh0wsomeattractivitypr0perties0ftheso1ution(ast-oo).Similarresultsf0rparab0licequati0nscanbefounde-g.in[2],[3].Letflbeab0unded0pensubset…  相似文献   

12.
1 IntroductionWe deal with the problem{ it:;,."--'"'::3of (11)where 9 C RN, N 2 3 is a bounded domain with smooth boundary 0fl, 0n = ro U r1, ro andYl have (N -- 1)-dinlensiollal Hausdorff nleasuret r E L'(r1), yt 2 0, V * 0 on r1, 7 denotesthe u11it outward normal and p = 2* = ee is the critical SoboleY exponent fOr the Sobolevembedding V(O) - H(O), V(fl) = {u E H'(fl) l u = 0 on ro}'The case ro and r1 have positive (N -- 1)-dimellsional Hausdoor measure aud p = 0on r1 in (1.1), has…  相似文献   

13.
The solutions of linear system of elliptic type equations with first order isdiscussed by using the method of several complex analysis and, a series of newextended results of the solutions for the system of elliptic type are obtained.  相似文献   

14.
一类非线性波动方程的显式精确解   总被引:14,自引:0,他引:14  
本文用直接方法和假设的一种结合求出了一类较广泛的非线性波动方程utt-a1uxx+a2ut+a3u+a4uS^2+a5u^3=0的一些显式精确行波解,贱个有重要的非线性数学物理方程,如φ^4方程,Klein-Gordon方程,Sine-Gordon方程,及Sinh-Gordon方程的近似,Landau-Ginzburg-Higgs方程,Duffing方程,非线性电报方程等都可作为该方程的特殊情形得  相似文献   

15.
本文研究了一类拟线性椭圆方程,其中非线性项f在无穷远处(p-1)-次线性增长,非线性项g在无穷远处超线性增长.利用三临界点定理,获得了该类方程多重解的存在性,结果推广了Kristaly等人最近的相关结果.  相似文献   

16.
In this article, we are concerned with the strong solutions of the coupled Navier-Stokes-Poisson equations for isentropic compressible fluids in a domain ΩR3. We prove the local existence of unique strong solutions provided that the initial data μ0 and μ0 satisfy a nature compatibility condition. The important point in this article is that we allow the initial vacuum: the initial density may vanish in an open subset of Ω. This is achieved by getting some uniform estimates and using a Schauder fixed point theorem.  相似文献   

17.
18.
1IntroductionInthispaper)weconsidertheexistenceofmultiplenonnegativesolutionsoftheequationwi'thboundaryconditionandrealnumberA>0.Whenthefunctionf(y)inequation(1.l)isoftheformf(y)=y,theboundaryvalueproblem(1.1),(1.2)describesthedeformationsofanelasticbeambothofwhoseendssimplysupportedat0and1.In[1],MaRuyunstudiedtheequationHeprovedtheexistenceofatleastonepositivesolutioniffiseithersuperlinearorsublinear,i.e.OurpurposehereistogiveanexistenceresultformultiplenonnegativesolutionstoBVP(1.1),(1.2)…  相似文献   

19.
周芳 《数学杂志》2012,32(1):79-91
本文研究了出现在半导体器件或者等离子中的多维双极Euler-Poisson方程,证明了它的初值问题的C1解在Besov空间的整体存在性,同时也得到了在二维和三维情形下,速度的璇度以指数的速率收敛到零.  相似文献   

20.
李宝麟  苟海德 《数学杂志》2015,35(3):567-578
本文研究了一类滞后型泛函微分方程的有界变差解.利用Henstock-Kurzweil积分与Schauder不动点定理,在Henstock-Kurzweil积分下,得到了这类滞后型泛函微分方程有界变差解的存在性定理,推广了一些相关的结果.  相似文献   

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