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1.
考虑包含测度μ的椭圆型方程-divA(x,u,u)+B(x,u,u)=μ,在G内,ξ·A(x,u,ξ)|ξ|p-f0(x),1<p<n,|A(x,u,ξ)|κ|ξ|p-1+f1(x),κ1,|B(x,u,ξ)|c(x)|ξ|γ+f2(x),p-1γp在γ=p-1的情况,为证有界解的Hlder连续性,只需c(x)∈Ln(G)  相似文献   

2.
关于面积平均p叶函数(Ⅱ)   总被引:1,自引:0,他引:1  
董新汉 《数学进展》1993,22(5):441-448
假设f(z)=z^p(1+Σ^∞n=1an^z^nk)是△={|z|<1}内面积平均p叶的(如果必要,△={|z|<1}\(-1,0])。本文的主要结论是:(1)如果设M(r)=max|f(z)|,则(1-r)2p/kM(r)→αk≤1(r→1),αk=1的充要条件是f(z)=z^p(1-xz^k)^-2p/k,|x|=1。进一步,如果1≤k<4p,我们有|an|n^1-2p/k→αkГ(2p/k  相似文献   

3.
一个反应扩散过程的门槛结果   总被引:3,自引:0,他引:3  
王明新 《数学学报》1994,37(6):735-743
本文讨论反应扩散方程Cauchy问题(ut-△u=u^p-u^p-u,X∈R^n,t∈(0,T),u(x,0)=u0(x)≥0,X∈R^n,解的整体存在性,渐近性质和Blow-up问题,其中1<q<p<n+2/n-2,n≥3或者1<q<p+∞,n=2.得到门槛结果。  相似文献   

4.
杨微生 《数学进展》1997,26(6):529-536
本文给出了消失Bergman-Carleson测度的一个特征,证明了:当f∈H(B),0<p<∞时,f∈B0等价于lim|z|→1|Δf(z)|=0,等价于lim|a|→1∫B|Δf(z)|pJRφa(z)dv(z)=0,等价于Δf(z)|pdv(z)是消失Bergman-Carleson测度.  相似文献   

5.
该文给出了非线性波动方程un=△u+f(u),(f(u)=u^p,p〉1)的Cauchy问题在函数空间C^k0(R^n)的原点领域有古典整体解的一个必要条件:1/2(u(0)^2L2+ut(0)^2L2)-∫R^n∫^u00f(s)dsdx≤0,并且证明了1〈p〈^n^2+n+2/n(n-1),n≠1(n=1,1〈p〈+∞)古典解与广义解有相同的生命跨度,同时给出了生命跨度的上界估计。  相似文献   

6.
关于Fujita型反应扩散方程组的Cauchy问题   总被引:5,自引:1,他引:5  
张凯军  王亮涛 《数学学报》1997,40(5):717-732
本文研究Fujita型反应扩散方程组ut-Δu=α1|u|q1-1u+β1|v|p1-1v,(x∈RN,t>0),vt-Δv=α2|u|q2-1u+β2|v|p2-1v,u(x,0)=u0(x)0,v(x,0)=v0(x)0,(x∈RN)Lp解的整体存在性和有限时间Blow up问题.这里qi>1,pi>1(i=1,2),α10,α2>0,β1>0,β20,1p+∞.  相似文献   

7.
最佳L2局部逼近存在唯一的充分必要条件   总被引:1,自引:0,他引:1  
本文给出了最佳L2局部逼近的存在唯一性定理,设f∈L2(0,δ),Sn=span(u0,u1,...Un-1)C^n-1(0,δ),且detWn(u0,u1,...un-1;0)≠0,那么,当x→0时,网(Px(f,Sn)收敛于Sn中某元素P0(f,Sn)的充要条件为:f=Pn-1+h,其中Pn-1(t)=n-1∑i=1aiti(h,1)x=0(X^n),x→0,且P0(f,Sn)=UW^-1nA  相似文献   

8.
带粗糙核的多线性振荡奇异积分   总被引:2,自引:0,他引:2  
胡国恩 《数学进展》1997,26(1):50-59
本文考虑多线性算子TAf(x)=∫RneiP(x,y)Ω(x-y)|x-y|n+mRm+1(A;x,y)f(y)dy,n2,其中P(x,y)是Rn×Rn中的实值多项式,Ω是零次齐次函数且满足m阶消失性条件,Rm+1(A;x,y)=A(x)-|α|mDαA(y)(x-y)α,对任何|α|=m,DαA∈BMO(Rn).证明了Ω∈Lq(Sn-1)且q>1时,对任何1<p<∞,‖TAf‖pC(n,m,p,degP)|α|=m‖DαA‖BMO‖f‖p  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.
胡克 《数学杂志》1993,13(4):413-418
设f(z)=z+Σanz^n为单位园|z|<1内解析且平均单叶,记其族为M又设{f(z)/z}^λ=1+Σ^∞n=1Dn(λ),λ>0,本文说明了:定理一 若f∈M,λ>0,则:Σ^∞k=1{||Dk(λ)|-|Dk-1(λ)||/dk(λ)}^2≤An,n=2,3,…其中A为绝对常数。dk(h)=h(h+1)…(h+k-1)/k!当λ=1/2,f∈s时为I.V.Milm所证明。定理二 若f∈M并  相似文献   

11.
Optimal control of nonlinear evolution inclusions   总被引:1,自引:0,他引:1  
In this paper, we study the optimal control of nonlinear evolution inclusions. First, we prove the existence of admissible trajectories and then we show that the set that they form is relatively sequentially compact and in certain cases sequentially compact in an appropriate function space. Then, with the help of a convexity hypothesis and using Cesari's approach, we solve a general Lagrange optimal control problem. After that, we drop the convexity hypothesis and pass to the relaxed system, for which we prove the existence of optimal controls, we show that it has a value equal to that of the original one, and also we prove that the original trajectories are dense in an appropriate topology to the relaxed ones. Finally, we present an example of a nonlinear parabolic optimal control that illustrates the applicability of our results.This research was supported by NSF Grant No. DMS-88-02688.  相似文献   

12.
In contrast with the analogous situation for a triangle, the cevians that join the vertices of a tetrahedron to the points where the faces touch the insphere (or the exspheres) are not concurrent in general. This observation led the present author and P. Walker in [4] to devise alternative definitions of the Gergonne and Nagel centers of a tetrahedron that do not assume the concurrence of such cevians and that coincide with the ordinary definitions in the case of a triangle. They then proved that the Gergonne center exists and is unique for all tetrahedra and that the Nagel center, though unique, exists only for tetrahedra that satisfy certain conditions. In this article, we extend these definitions to simplices of any dimension. By keeping the requirement that the Gergonne center be interior and relaxing such a condition for the Nagel center, we prove that both centers exist and are unique for all simplices, thus polishing the definitions and generalizing the results of the above-mentioned article.  相似文献   

13.
Given an undirected graph, a star partition is a partition of the nodes into subsets with at least two nodes so that the subgraph induced by each subset has a spanning star. Star partitions are related to well-known problems concerning domination in graphs and edge covering. We focus on the Constrained Star Partition Problem (CSP) that asks for finding a star partition of given cardinality. The problem is new and presents interesting peculiarities. We explore the relation between the cardinalities of star partitions and domatic bipartitions, showing that there are star partitions of any cardinality between minimum and maximum values, and that a similar but weaker result holds for domatic bipartitions. We study the computational complexity of different versions of star partition and domatic bipartition problems, proving that most of them, in particular CSP, constrained domatic bipartition and balanced domatic bipartition, are NP-complete. We also show that star partition problems are polynomial on trees and, more generally, on bounded treewidth graphs. We introduce an integer linear programming formulation that defines a polytope containing all the star partitions of a graph, showing that its vertices have only integral components for trees, which implies that linear programming can be used to solve weighted star partition problems on trees.  相似文献   

14.
Recently, many have argued that phenomenal content supervenes on representational content; i.e. that the phenomenal character of an experience is wholly determined (metaphysically, not causally) by the representational content of that experience. This paper it identifies many counter-examples to intentionalism. Further, this paper shows that, if intentionalism were correct, that would require that an untenable form of representational atomism also be correct. Our argument works both against the idea that phenomenal content supervenes on “conceptual” content and also against the idea that it supervenes on “non-conceptual” content. It is also shown that the distinction between conceptual and non-conceptual content has been wrongly conceived as distinction between different kinds of information: in fact, it is a distinction between ways of packaging information that is, in itself, neither conceptual or non-conceptual.  相似文献   

15.
In this note, we assume that the reported income is related to the true income by the so-called ‘error-in-variables’ model, a model which assumes that the observed incomes are under-reported. In the context of this model, the distribution of the reported income suitably truncated below coincides with that of the true income, and suitable truncated above with that of the random proportion of the reported income to the true income if, and only if, the distribution of the true income is Pareto and that of the proportion is of the power function form.  相似文献   

16.
We are given a set of items that must be produced in lots on a capacitated production system throughout a specified finite planning horizon. We assume that the production system is subject to random failures, and that any maintenance action carried out on the system, in a period, reduces the system’s available production capacity during that period. The objective is to find an integrated lot-sizing and preventive maintenance strategy of the system that satisfies the demand for all items over the entire horizon without backlogging, and which minimizes the expected sum of production and maintenance costs. We show how this problem can be formulated and solved as a multi-item capacitated lot-sizing problem on a system that is periodically renewed and minimally repaired at failure. We also provide an illustrative example that shows the steps to obtain an optimal integrated production and maintenance strategy.  相似文献   

17.
It is known that the only positive derivation on a reduced archimedean f-ring is the zero derivation. We investigate derivations on general archimedean lattice-ordered rings. First, we consider semigroup rings over cyclic semigroups and show that, in the finite case, the only derivation that is zero on the underlying ring is the zero derivation and that, in the infinite case, such derivations are always based on the derivative. Turning our attention to lattice-ordered rings, we show that, on many algebraic extensions of totally ordered rings, the only positive derivation is the zero derivation and that, for transcendental extensions, derivations that are lattice homomorphisms are always translations of the usual derivative and derivations that are orthomorphisms are always dilations of the usual derivative. We also show that the only positive derivation on a lattice-ordered matrix ring over a subfield of the real numbers is the zero derivation, and we prove a similar result for certain lattice-ordered rings with positive squares. The second author thanks Hamilton College for its support of his visits to the first author in Houston. He also thanks John Miller for his friendship and hospitality over the last thirty years.  相似文献   

18.
We consider a parallel fiber‐reinforced periodic elastic composite that present an imperfect contact of spring type between the fiber and the matrix. We use the elliptic integral of Cauchy type for solving the plane strain local problems that arise from the asymptotic homogenization method. Several general conditions are assumed, which include that the fibers are disposed of arbitrary manner in the local cell, that all fibers present contact perfect with different constants of imperfection, and that their cross section is a smooth closed arbitrary curve. We find that there are infinity solutions for these problems, and we find relations between these solutions and effective coefficients of the composite. Finally, we obtain analytic formulae for the circular fiber case and show some numerical examples. Copyright © 2016 John Wiley & Sons, Ltd.  相似文献   

19.
The complementarity problem is theoretically and practically useful, and has been used to study and formulate various equilibrium problems arising in economics and engineerings. Recently, for solving complementarity problems, various equivalent equation formulations have been proposed and seem attractive. However, such formulations have the difficulty that the equation arising from complementarity problems is typically nonsmooth. In this paper, we propose a new smoothing Newton method for nonsmooth equations. In our method, we use an approximation function that is smooth when the approximation parameter is positive, and which coincides with original nonsmooth function when the parameter takes zero. Then, we apply Newton's method for the equation that is equivalent to the original nonsmooth equation and that includes an approximation parameter as a variable. The proposed method has the advantage that it has only to deal with a smooth function at any iteration and that it never requires a procedure to decrease an approximation parameter. We show that the sequence generated by the proposed method is globally convergent to a solution, and that, under semismooth assumption, its convergence rate is superlinear. Moreover, we apply the method to nonlinear complementarity problems. Numerical results show that the proposed method is practically efficient.  相似文献   

20.
Non-attendance to meaning by students is a prevalent phenomenon in school mathematics. Our goal is to investigate features of instruction that might account for this phenomenon. Drawing on a case study of two high school algebra teachers, we cite episodes from the classroom to illustrate particular teaching actions that de-emphasize meaning. We categorize these actions as pertaining to (a) purpose of new concepts, (b) distinctions in mathematics, (c) mathematical terminology, and (d) mathematical symbols. The specificity of the actions that we identify allows us to suggest several conjectures as to the impact of the teaching practices observed on student learning: that students will develop the belief that mathematics involves executing standard procedures much more than meaning and reasoning, that students will come to see mathematical definitions and results as coincidental or arbitrary, and that students’ treatment of symbols will be largely non-referential.  相似文献   

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