非齐次守恒律方程分片光滑解的粘性方法

1　引　　言考虑非齐次守恒律方程ut+f(u) x =g(u) ,　　 -∞ 0 ,(1 .1 )u(x,0 ) =u0 (x) ,　　 -∞ 0 , (1 .5)g∈ C3且 g是 Lipschitz连续的 ,Lipschitz系数为 L . (1 .6 )对于一般守恒律齐次方程 ,粘性解逼近熵解的收敛阶为 O(ε ) [1 ] .在 f严格凸的条件下 ,其收敛速度可以提高到 O(ε|lnε|+ε) [2 ] ,[3] .本文考虑具有条件 (1 .5) (1 .6 )的非齐次方程(1 .1 ) ,在较广泛的一类初值条件下…     

一维p-Laplacian奇异Sturm-Liouville边值问题的正解

本文在条件 0 ≤ f+ 0 <p(M1) ,p(m1) 1 ,f+ 0 =limu→ 0f(u)p(u) ,f-∞ =limu→∞f(u)p(u) ,f-0 =limu→ 0f(u)p(u) ,f+ ∞ =limu→∞f(u)p(u) ,g在区间 [0 ,1 ]的端点可以具有奇性 .     

指数分布族参数的渐近最优与可容许的经验Bayes估计

在平方损失下 ,构造了指数族 { f(x|λ) =λe-λx,λ >0 ,x >0 }的参数λ的渐近最优与可容许的经验Bayes估计 ,即δn=(n +u + 1n1φ(n) + 1) β1+ βX,其中X1,X2 ,…Xn(历史样本 )和X(当前样本 )独立同分布于 f(x) ,Sn= ni=11n(1+ βXi) ,φ(n) =1n(Sn+ 1n(1+ βX) +v- 1) ,u >0 ,v >0 ,β >0 (已知 )为任意的实数 ,并证明了该估计的收敛速度为O(n- 1)。     

一维非齐次BBM方程周期边界问题的整体吸引子

研究了一维非齐次方程BBM方程ut-uxxt-αφ(u)x=g(x)+βf(u)+γuxx(α>0,β>0,γ>0),u(x+2π,t)=u(x,t),u(x,0)=u0(x)的周期边界问题.利用Sobolev插值不等式,对解做关于时间t的一致性先验估计,证明了该问题的整体吸引子的存在性.     

EXISTENCE OF NONTRIVIAL SOLUTIONS FOR GENERALIZED QUASILINEAR SCHRDINGER EQUATIONS WITH CRITICAL OR SUPERCRITICAL GROWTHS

In this paper,we study the following generalized quasilinear Schrdinger equations with critical or supercritical growths-div(g~2(u)▽u) + g(u)g′(u)|▽u|~2+ V(x)u = f(x,u) + λ|u|~(p-2)u,x∈R~N,where λ0,N≥3,g:R → R~+ is a C~1 even function,g(0) = 1,g′(s) ≥ 0 for all s ≥ 0,lim_(|s|→+∞)g(s)/|s|~(α-1):= β 0 for some α≥ 1 and(α-1)g(s) g′(s)s for all s 0 and p ≥α2*.Under some suitable conditions,we prove that the equation has a nontrivial solution for smallλ 0 using a change of variables and variational method.     

双重退化抛物型方程整体解的存在性和L~∞估计

文考虑双重退化抛物型方程ut=div(|u|r|u|m--2u)+A(u)带有零边界条件的初边值问题的整体解存在性,唯一性和解在t=0,∞处的L∞模估计.证明了当u0∈Lq(Ω)时,整体解u(t)满足估计‖u(t)‖∞≤C(1+t-λβ)(1+t)-β/M,‖(u(t)|r/(m-1)u(t))‖m≤C(1+t-μ)(1+t)-σ,t＞0,这里λ,μ,σ,M,β为依赖于m,q,N和r的适当正常数.     

一类非线性椭圆边值问题解的存在性

目前 ,对 s——拉普拉斯算子△s的研究是较为活跃的数学课题 .原因在于算子 -△s与许多物理现象有关 .比如 :反射扩散问题 ,石油提取问题等等 .基于此因 ,在文 [3]的基础上 ,我们将继续研究以下非线性边值问题在 Ls(Ω) ,( 1 2 nn+1 )中解的存在条件 .-△su +g( x,u) =f几乎处处在Ω中-〈 ,| u|s- 2 u〉 =0几乎处处在Γ上其中 f∈Ls( Ω)给定 ,Ω Rn( n 1 ) ,△su=div( | u|s- 2 u) ,g∶Ω× R→ R满足 Caratheodory条件 .本文把文 [3]关于非线性边值问题 @在 Lp( Ω) ( 2 p<+∞ )空间中解的存在性的研究推广到 Ls( Ω) ( 1 2 nn+1 )空间中 .     

一类非线性双曲-抛物耦合问题的A.D.I.Galerkin方法

1　引　言考虑三维非线性双曲 -抛物耦合初边值问题 :utt- . (a1 (X,t,u) u) +b1 (X,t,u,v) . u　　　　 +α1 e. v =f(X,t,u,v) ,X∈Ω,t∈ J.vt-a2 Δv +b2 (X,t,u,v) . v　　　　 +α2 e. ut=g(X,t,u,v) ,X∈Ω,t∈ J.u(X,t) =v(X,t) =0 , X∈ Ω ,t∈ J.u(X,0 ) =u0 (X) ,ut(X,0 ) =ut0 (X) ,v(X,0 ) =v0 (X) ,X∈Ω.(1 .1 )其中 ,X=(x1 ,x2 ,x3) ,Ω=(c1 ,d1 )× (c2 ,d2 )× (c3,d3)为 R3中矩形区域 ,边界 Ω . J=[0 ,T] ,T>0为一正常数 .b1 ,b2 ,f,g均为已知光滑函数 (其中 b1 ,b2 为向量函数 ) ,且关于 u,v满足 L…     

一阶微分方程的渐近平稳和周期边值问题

假定函数 f∈C[R_+×R,R],我们考虑非线性问题u'=f(t,u),u(t_0)=u_0,t_0≥0.(A)[1]附录的定理 A.1.2就(A)的渐近平稳(Asymptotic Equilibrium)给出如下的定理 A。假定 g(t,u)∈C[R_+×R_+,|R_+]对于每个 t 关于 u 单调非减,且使得|f(t,u)|≤g(t,|u|),(t,u)∈R_+×R.如果问题u′=g(t,u),u(t_0)=u_0≥0的所有解 u(t)在[t_0,∞)上有界,那么问题(A)渐近平稳.利用这个定理,[1]在假定,f(t,u)满足单边的 Lipschitz 条件     

一类非线性Schrdinger-Maxwell方程基态解的存在性

本文研究了如下Schrdinger-Maxwell方程基态解的存在性问题{-△u+V(x)u+K(x)φ(x)u=b(x)|u|p-1u+λg(x,u)in R~3,-△φ=K(x)u~2in R~3,其中λ0,V(x)∈C~1(R~3,R),且V(x)0.△在K,g,b满足一定的假设条件下,且0p1时,利用变分法和临界点理论,获得了基态解的存在性.该结论推广了文献[7]的结果.     

Almost surely convergent summands of a random sum

We find a sufficient condition for a.s. convergence to zero of summands given that a sum of two sequences of random variables a.s. converges to zero. The condition turns out to be weaker than that used in the monograph by Loeve and in a paper by Martikainen. Our result is also used in construction of a counter-example regarding the a.s. convergence of a rearranged series.     

随机级数的自然边界

在建立一个重要引理的基础上,利用有关对称随机级数的S-可和性及a.s.收敛关系的成果,可得到下列结果二维对称随机解析级数的收敛边界几乎必然是自然边界.     

污染线性模型的非参数估计

Abstract. In this paper, the following contaminated linear model is considered:     

分组删失数据下生存函数Turnbull估计的强收敛性

证明了分组删失情形下生存函数的Turnbull估计具有强极限，并给出极限值所满足的方程。     

关于完备随机内积模中的Lax-Milgram定理的注记

设(S,X)为数域K上以σ-有限测度空间(Ω,A,μ)为基的完备的RIP-模,而且α:S×S→L(μ,K)满足如下条件:(A)存在ξ∈L (μ),使得a(p,q)ξ·X~p·X~q,p,q∈S;(B)a是coercive(即,存在η∈L (μ),使得a(p,p)η·X~p2,p∈S且μ({ωη(ω)=0})=0);(C)对每个q∈S,a(·,q):S→L(μ,K)是模同态,且对每个p∈S,a(p,ξq1 ηq2)=ξ-a(p,q1) η-a(p,q2),q1,q2∈S及ξ,η∈L(μ,K).则存在唯一的连续模同态A:S→S使A-1存在且μ-a.s.有界,还满足:(1)a(p,q)=XA(p),q,p,q∈S;(2)X~A-1(p)1ηX~p,p∈S.     

STABILITY OF SOME KIND OF STOCHASTIC DIFFERENTIAL EQUATION

In this paper,a kind of stochastic differential equation is investigated and the almost sure exponential stability of the equation is obtained using Gronwall's inequality.Further,we also give other noise intensity function to keep the stability of the system.     

Fuzzy值函数的Sugeno积分性质

在Fuzzy值函数的Sugeno积分基础上,研究了几乎处处收敛的Fuzzy值函数及其序列的积分收敛性,得到了一些新的积分性质．     

Unbiased Bayes estimates and improper priors

Given two random variables (X, Y) the condition of unbiasedness states that:E(X |Y=y)=y andE(Y |X=x)=x both almost surely (a.s.). If the prior onY is proper and has finite expectation or non-negative support, unbiasedness impliesX=Y a.s. This paper examines the implications of unbiasedness when the prior onY is improper. Since the improper case can be meaningfully analysed in a finitely additive framework, we revisit the whole issue of unbiasedness from this perspective. First we argue that a notion weaker than equality a.s., named coincidence, is more appropriate in a finitely additive setting. Next we discuss the meaning of unbiasedness from a Bayesian and fiducial perspective. We then show that unbiasedness and finite expectation ofY imply coincidence betweenX andY, while a weaker conclusion follows if the improper prior onY is only assumed to have positive support. We illustrate our approach throughout the paper by revisiting some examples discussed in the recent literature.This work was partially supported by C.N.R. grant N.80.02970.10 (G.C.) and by C.N.R. grant altri interventi (P.V.). A preliminary draft was written while the Authors were visiting the Department of Statistics at Carnegie Mellon University.The paper is the result of close cooperation between the two authors. However subsections 3.1 and 3.3 are mainly due to G.C. while subsection 3.2 and section 4 are mainly due to P.V.     

Epi-convergence almost surely, in probability and in distribution

The paper deals with an epi-convergence of random real functions defined on a topological space. We follow the idea due to Vogel (1994) to split the epi-convergence into the lower semicontinuous approximation and the epi-upper approximation and localize them onto a given set. The approximations are shown to be connected to the miss- resp. hit-part of the ordinary Fell topology on sets. We introduce two procedures, called “localization”, separately for the miss-topology and the hit-topology on sets. Localization of the miss- resp. hit-part of the Fell topology on sets allows us to give a suggestion how to define the approximations in probability and in distribution. It is shown in the paper that in case of the finite-dimensional Euclidean space, the suggested approximations in probability coincide with the definition from Vogel and Lachout (2003). The research has been partially supported by Deutsche Forschungsgemeinschaft under grant No. 436TSE113/40, by the Ministry of Education, Youth and Sports of the Czech Republic under Project MSM 113200008 and by the Grant Agency of the Czech Republic under grant No. 201/03/1027.     

随机自反随机赋范模上的平均遍历定理(英文)

本文对随机自反随机赋范模上的几乎处处幂有界的随机线性算子证明了一个平均遍历定理,这一定理推广和改进了几个已知的重要的结果.