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1.
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   

2.
Periodic Solutions of Porous Medium Equations with Weakly Nonlinear Sources   总被引:1,自引:0,他引:1  
§ 1.Introduction ThispaperisconcernedwiththetimeperiodicsolutionsoftheporousmediumequationswithweaklynonlinearsourcesandwiththeDirichletboundaryvaluecondition ,namely ,theproblem u t =Δ(|u|m- 1u) +B(x ,t,u) +f(x ,t) inΩ×R ,(1 .1 )u(x ,t) =0 on Ω×R , (1 .2 )u(x ,t+ω) =u(x ,t) in Ω×R ,…  相似文献   

3.
§ 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   

4.
§ 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   

5.
Considerthefirstinitial boundaryvalueproblem u t=div q( u) ,  (x,t) ∈QT,(1 )u(x,t) =0 ,  (x,t) ∈ Ω× (0 ,T) ,(2 )u(x,0 ) =u0 (x) , x∈Ω ,(3 )whereΩisaboundeddomaininRNwithsmoothboundary Ω ,QT=Ω× (0 ,T) , q = φ ,φ∈C1(RN) ,and φ , qsatisfythestructureconditions(λ|ξ|1+δ-1 ) +≤ φ(ξ) ≤Λ|ξ|1+δ+ 1 ,  ξ∈RN,(4 )| q(ξ) …  相似文献   

6.
§ 1.Introduction Letabeameasurablefunction ,bea φ∈S(R)nonnegativefunction ,and 0 <r <∞ .Definecommutatorsasfollows :Cra( f) (x) =supx∈Q1|Q|∫Q|a(x) -a( y) |r|f( y) |dy ,( 1 .1 )andΦra( f) (x) =supε>0∫Rn|a(x) -a( y) |rφε( |x- y|)|f( y) |dy ,( 1 .2 )whereQdenotesacubeandφε(t) =1εnφ tε .Thesetwooperat…  相似文献   

7.
§1. IntroductionLetΩbeaboundedsmoothdomainintheHeisenberggroupHn,weareconcernedwiththeproblemofsemilinearsubellipticLaplaceequation-ΔHnu=up+f(x,u),inΩ,u>0,    inΩ,(1.1)u=0,    onΩ,wherepisarealnumber,f(x,y)satisfiessuitableassumptions(seebelowsectio…  相似文献   

8.
Inarecentpaper [1],YehasdemonstratedthatthesingularnonlinearellipticequationΔu =f(u , u ,x ) /uλ, x∈R2 ,0 <λ<1hasapositiveentiresolutionundersomeconditionsimposedonf.Problemsoffindingpositiveentiresolutionstoellipticequationshavebeenstudiedbymanyauthorssincetheyh…  相似文献   

9.
§1 IntroductionInthispaperwecontinuetoconsidertheexistenceofpositiveradialsolutionsforthequasilinearellipticequation-div(|Du|p-2Du)=f(u) inΩ,(1)u(x)=0 onΩ,wherex∈Rn,n≥2,Ω={x:a<|x|<b,a,b>0},andp>1,f∈C1((0,∞))∩C0([0,∞))satisfyingthefollowinghypotheses…  相似文献   

10.
试卷 1 (3月 )1 解不等式|x- 4|- |x- 1||x- 3|-|x- 2 | <|x- 3| |x- 2||x- 4| .2 已知一个递减等差数列的前 7项的 5次幂之和等于 0 ,而它们的 4次幂之和等于 51 .求这个数列的第 7项 .3 在区间 [- 92 π ,- 32 π]上 ,求下列方程的所有的根 :cosxsin x4 91 0 sinx 2sin x4cos x2 sin x4 - 12 cos x4 - 92 0 =0 .4 经过梯形ABCD的腰AB的中点K作出AB的垂线与边CD相交于点L .已知四边形AKLD的面积是四边形BKLC的面积的 5倍 ,CL=3,DL =1 5,KC =4.求线段K…  相似文献   

11.
In this paper, the authors cosider the derivation of the exact distributions of the ratios of the extreme roots to the trace of the Wishart matrix. Also, exact percentage points of these distributions are given and their applications are discussed.  相似文献   

12.
通过建立常微分方程模型 ,分析了预防和隔离措施对 SARS发病率的影响 ,并把计算结果与实际统计数据进行了比较 ,结果表明 ,及时高效的预防和隔离措施能够有效地控制 SARS的传播 .  相似文献   

13.
Let { } be a sequence of finitely presented groups with generating setA={a1, …, am}, and letRk be the symmetrized set of words over the alphabetAA−1 obtained from the defining words and their inverses by all cyclic shifts. We shall assume that the words inRk are cyclically irreducible, and their lengths tend to ∞ ask increases. In the paper, it is proved that ifRk satisfies the small cancellation conditionC'(1/6) and the number of relators increases not very rapidly with increasingk, then the growth rate ψ(Gk) tends to 2m−1 ask→∞. Translated fromMatematicheskie Zametki, Vol. 65, No. 4, pp. 611–617, April, 1999.  相似文献   

14.
This paper shows that the noncommutative generalization of the A-polynomial of a knot, defined using Kauffman bracket skein modules, together with finitely many colored Jones polynomials, determines the remaining colored Jones polynomials of the knot. It also shows that under certain conditions, satisfied for example by the unknot and the trefoil knot, the noncommutative generalization of the A-polynomial determines all colored Jones polynomials of the knot.

  相似文献   


15.
宏观因素影响下的系统中元件重要性研究   总被引:9,自引:0,他引:9  
为研究复杂系统在工作环境中其组成元件对系统安全运行的重要性,将汪培庄先生的因素空间理论与笔者提出的空间事故树理论相结合,构造了一套元件重要性研究方法.构建系统T={U,C,D},将元件作为研究对象集合U,系统工作的宏观环境作为因素集C,元件重要性排序集作为D.对宏观环境中的工作时间a1和温度a_2进行划分形成不同的状态区域S_q,计算在S_q中元件xj的失效权重γ(AS_q(x_j))和在S_q中系统T的失效权重δ(AS_q(T))),从而得到x_j在S状态下的等效失效权重Z(AS_q(x_j)),研究状态S_q下的原件重要性排序D_η,及元件x_j失效性对a_1及a_2的敏感性.使用一个实际的电气系统维修情况统计资料,使用上述方法进行了研究,结果表明:不同工作环境下元件对系统的重要程度是不同的.元件对温度和使用时间是敏感的,并得到了在1030°且5030°且5075d环境下工作系统可靠性是最高的结论.在给定工作环境下,重要性大的元件多储备,重要性小的元件少储备,以满足系统维修需要,并指导实际工程.  相似文献   

16.
The stability of the stationary solution of the thermistor problem 1s proved using a Liapunov functional for a class of physically relevant electrical conductivity.  相似文献   

17.
一类树并的补图的色唯一性   总被引:10,自引:0,他引:10  
彻底解决了一类不可约树并的补图是色唯一的 ,并得到了一些图的伴随多项式的最小根的重要规律 .  相似文献   

18.
19.
The valuation of levered investment in the practice is made with the WACC approach, even if the superior technique of the APV is available. The paper shows that the APV can be interpreted as the arbitrage free value of the portfolio made by an investment and a supporting loan. Therefore the WACC evaluation, generally different from the APV, allows for arbitrage. We provide various conditions which completely characterize the sign of the error as a functions of all the variables entering the model.  相似文献   

20.
For a Riesz operator T on a reflexive Banach space X with nonzero eigenvalues denote by Ei; T) the eigen-projection corresponding to an eigenvalue λi. In this paper we will show that if the operator sequence is uniformly bounded, then the Riesz operator T can be decomposed into the sum of two operators Tp and Tr: T = Tp + Tr, where Tp is the weak limit of Tn and Tr is quasi-nilpotent. The result is used to obtain an expansion of a Riesz semigroup T(t) for t ≥ τ. As an application, we consider the solution of transport equation on a bounded convex body.  相似文献   

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