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设是一个有界区域,考虑问题: D_i(g(|Du|~2)|Du|~(p-2)D_iu)=0,x∈Ω其中g(0)=0;当t>0时,g(t)>0.加上g(t)必须满足的条件.利用这些条件,我们获得上述退化椭圆型方程的广义解的局部正则性。 在文中,我们运用了逼近法和证明主要引理的一些技巧。 最后,我们给出两个具体例子。 相似文献
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本文考虑Boussinesq方程一类合适弱解的部分正则性.我们先运用广义能量不等式和奇异积分理论得到一些无维量的估计;再通过合适弱解满足的等式,运用迭代技巧,推导出温度场的小性估计;最后由尺度分析(scaling arguments)得到了一类合适弱解的部分正则性. 相似文献
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本文在较弱的椭圆条件(H_1)和更一般的增长条件(H_5)下,证明了二阶非线性椭圆组弱解的C~(1,σ)-部分正则性. 相似文献
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研究了一类趋化性生物模型行波解的存在性和正则性.通过直接计算得到了其行波解存在的充分必要条件;在一定条件下,研究了行波解的正则与非正则的性质;在特殊情形下给出了行波解的显式解. 相似文献
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考虑了C1-正则半群{S(t)}t≥0和C2-正则半群{T(t)}t≥0之差Δ(t)=S(t)C1-T(t)C2在一定假定条件下的紧性. 相似文献
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Retakh条件(M0)与弱(序列式)紧正则性 总被引:1,自引:0,他引:1
本文研究了弱(序列式)紧正则诱导极限与凸弱(序列式)紧正则诱导极限.满足Retakh条件(Mo)的(LF)-空间必为凸弱(序列式)紧正则的,但未必为弱(序列式)紧正则的.对于弱序列式完备Frechet空间的可数诱导极限,Retakh条件(Mo)蕴涵弱(序列式)紧正则性.特别地,对于Kothe(LF)-序列空间Ep(1≤p<∞),Retakh条件(Mo)等价于弱(序列式)紧正则性.对于这类空间,利用Vogt的有关结论,给出了弱(序列式)紧正则性的特征. 相似文献
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通过数值方法,研究边界充分(逐段)光滑区域上的二维波动方程在部分Dirichlet边界控制下的正则性问题.数值结果表明:在所选条件下,系统是Salamon-Weiss意义下正则的. 相似文献
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研究了无界区域Rn上Plate方程全局吸引子的正则性和有限分形维性.该方程的全局吸引子在相空间H2(Rn)×L2(Rn)的存在性已在先期文章建立,现在进一步证明该全局吸引子具有更好的正则性,即它是H4(Rn)×H2(Rn)的有界集并具有有限分形维数. 相似文献
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Mei-Qin Zhan 《Mathematical Methods in the Applied Sciences》1997,20(8):679-688
This paper addresses the question: when the frequency of collisions vanishes, will the solutions of the Landau system converge to the solutions of the Vlasov system? We give a positive answer to the question for solutions satisfying certain regularity conditions. © 1997 by B. G. Teubner Stuttgart–John Wiley & Sons Ltd. Math. Meth. Appl. Sci., Vol. 20, 679–688 (1997). 相似文献
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E. Rannou 《Discrete and Computational Geometry》1998,19(1):47-78
This paper investigates the complexity of stratification computation for semialgebraic sets. An upper bound for the computation
of canonical stratifications is given for a wide class of stratifying conditions called here admissible. For such conditions, the stratifying process is at most doubly exponential in the depth of the stratification. Usual conditions
of regularity like Whitney conditions (a) and (b) or Bekka condition (C) are admissible. A useful criterion and tools are
given in order to prove easily other admissibilities.
Received February 15, 1995, and in revised form January 29, 1997 and May 6, 1997. 相似文献
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Hamiltonian Pontryagin's Principles for Control Problems Governed by Semilinear Parabolic Equations 总被引:2,自引:0,他引:2
In this paper we study optimal control problems governed by semilinear parabolic equations. We obtain necessary optimality
conditions in the form of an exact Pontryagin's minimum principle for distributed and boundary controls (which can be unbounded)
and bounded initial controls. These optimality conditions are obtained thanks to new regularity results for linear and nonlinear
parabolic equations.
Accepted 17 March 1997 相似文献
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We obtain some point-based sufficient conditions for the metric regularity in Robinson’s sense of implicit multifunctions in a finite-dimensional setting. The new implicit function theorem (which is very different from the preceding results of Ledyaev and Zhu [Yu.S. Ledyaev, Q.J. Zhu, Implicit multifunctions theorems, Set-Valued Anal. 7 (1999) 209–238], Ngai and Théra [H.V. Ngai, M. Théra, Error bounds and implicit multifunction theorem in smooth Banach spaces and applications to optimization, Set-Valued Anal. 12 (2004) 195–223], Lee, Tam and Yen [G.M. Lee, N.N. Tam, N.D. Yen, Normal coderivative for multifunctions and implicit function theorems, J. Math. Anal. Appl. 338 (2008) 11–22]) can be used for analyzing parametric constraint systems as well as parametric variational systems. Our main tools are the concept of normal coderivative due to Mordukhovich and the corresponding theory of generalized differentiation. 相似文献
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指数族广义非线性随机系数模型是Smith &; Heitjan[10]和 Wei et al[11]所研究模型的推广。该文分别在模型离差 (dispersion) 的权不变和变异时,讨论了指数族 广义非线性随机系数模型的变离差的检验问题,得到了score检验统计量。并利用欧洲野兔数据,分别对正态分布模型、Γ 分布模型和
逆高斯分布模型说明检验方法的有效性。 相似文献
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Heinz‐Jürgen Flad Reinhold Schneider Bert‐Wolfgang Schulze 《Mathematical Methods in the Applied Sciences》2008,31(18):2172-2201
We study the asymptotic regularity of solutions to Hartree–Fock (HF) equations for Coulomb systems. To deal with singular Coulomb potentials, Fock operators are discussed within the calculus of pseudo‐differential operators on conical manifolds. First, the non‐self‐consistent‐field case is considered, which means that the functions that enter into the nonlinear terms are not the eigenfunctions of the Fock operator itself. We introduce asymptotic regularity conditions on the functions that build up the Fock operator, which guarantee ellipticity for the local part of the Fock operator on the open stretched cone ?+ × S2. This proves the existence of a parametrix with a corresponding smoothing remainder from which it follows, via a bootstrap argument, that the eigenfunctions of the Fock operator again satisfy asymptotic regularity conditions. Using a fixed‐point approach based on Cancès and Le Bris analysis of the level‐shifting algorithm, we show via another bootstrap argument that the corresponding self‐consistent‐field solutions to the HF equation have the same type of asymptotic regularity. Copyright © 2008 John Wiley & Sons, Ltd. 相似文献
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Christian Le Merdy 《Mathematische Zeitschrift》1999,230(1):47-62
We establish a transference result for -maximal regularity for the abstract Cauchy problem on Banach space. From this result we deduce counterexamples to -maximal regularity In particular we obtain an operator B without any -maximal regularity although it admits bounded imaginary powers with for all . We also derive an operator which satisfies -maximal regularity on bounded intervals [0, T[ but not on the half line
Received March 5, 1997; in final form October 10, 1997 相似文献
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F. Guillén–González M. A. Rodríguez–Bellido M. A. Rojas–Medar 《Mathematische Nachrichten》2009,282(6):846-867
In [3], L. Berselli showed that the regularity criterion ? u ∈ (0, T; L q (Ω)), for some q ∈ (3/2, + ∞], implies regularity for the weak solutions of the Navier–Stokes equations, being u the velocity field. In this work, we prove that such hypothesis on the velocity gradient is also sufficient to obtain regularity for a nematic Liquid Crystal model (a coupled system of velocity u and orientation crystals vector d ) when periodic boundary conditions for d are considered (without regularity hypothesis on d ). For Neumann and Dirichlet cases, the same result holds only for q ∈ [2, 3], whereas for q ∈ (3/2, 2) ∪ (3, + ∞] additional regularity hypothesis for d (either on ? d or Δ d ) must be imposed. On the other hand, when the Serrin's criterion u ∈ (0, T; L p (Ω)) with some p ∈ (3, + ∞] ([16]) for u is imposed, we can obtain regularity of the system only in the problem of periodic boundary conditions for d . When Neumann and Dirichlet cases for d are considered, additional regularity for d must be imposed for each p ∈ (3, + ∞] (© 2009 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim) 相似文献
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Ultraconvergence of the patch recovery technique 总被引:14,自引:0,他引:14
Zhimin Zhang. 《Mathematics of Computation》1996,65(216):1431-1437
The ultraconvergence property of a derivative recovery technique recently proposed by Zienkiewicz and Zhu is analyzed for two-point boundary value problems. Under certain regularity assumptions on the exact solution, it is shown that the convergence rate of the recovered derivative at an internal nodal point is two orders higher than the optimal global convergence rate when even-order finite element spaces and local uniform meshes are used.
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We study the regularity criteria for weak solutions to the incompressible magnetohydrodynamic (MHD) equations. Some regularity criteria, which are related only with u+B or u?B, are obtained for weak solutions to the MHD equations. Copyright © 2008 John Wiley & Sons, Ltd. 相似文献