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131.
Exact boundary controllability for 1‐D quasilinear wave equations with dynamical boundary conditions 下载免费PDF全文
Yue Wang Günter Leugering Tatsien Li 《Mathematical Methods in the Applied Sciences》2017,40(10):3808-3820
By equivalently replacing the dynamical boundary condition by a kind of nonlocal boundary conditions, and noting a hidden regularity of solution on the boundary with a dynamical boundary condition, a constructive method with modular structure is used to get the local exact boundary controllability for 1‐D quasilinear wave equations with dynamical boundary conditions. Copyright © 2016 John Wiley & Sons, Ltd. 相似文献
132.
Xiuwen Li Zhenhai Liu C. C. Tisdell 《Mathematical Methods in the Applied Sciences》2017,40(12):4548-4559
The aim of this paper is to deal with the existence of mild solutions and exact controllability for a class of fractional evolution inclusions with damping (FEID, for short) in Banach spaces. Firstly, we provide the representation of mild solutions for FEID by applying the method of Laplace transform and the theory of (α,κ)‐regularized families of operators. Next, we are concerned with the existence and exact controllability of FEID under some suitable sufficient conditions by using the method of measure of noncompactness and an appropraite fixed point theorem. Finally, an application to nonlinear partial differential equations with temporal fractional derivatives is presented to illustrate the effectiveness of our main results. Copyright © 2017 John Wiley & Sons, Ltd. 相似文献
133.
Exact controllability of nodal profile for 1‐D first order quasilinear hyperbolic systems with internal controls 下载免费PDF全文
Kaili Zhuang 《Mathematical Methods in the Applied Sciences》2017,40(18):6565-6580
For 1‐D first order quasilinear hyperbolic systems without zero eigenvalues, based on the theory of exact boundary controllability of nodal profile, using an extension method, the exact controllability of nodal profile can be realized in a shorter time by means of additional internal controls acting on suitably small space‐time domains. On the other hand, using a perturbation method, the exact controllability of nodal profile for 1‐D first order quasilinear hyperbolic systems with zero eigenvalues can be realized by additional internal controls to the part of equations corresponding to zero eigenvalues. Furthermore, by adding suitable internal controls to all the equations on suitable domains, the exact controllability of nodal profile for systems with zero eigenvalues can be realized in a shorter time. 相似文献
134.
Greg Hjorth 《Proceedings of the American Mathematical Society》2008,136(10):3647-3653
We show that domains of non-trivial trees have members. Using this, we show that smooth treeable equivalence relations have Borel transversals, and essentially countable treeable equivalence relations have Borel complete countable sections. We show also that treeable equivalence relations which are ccc idealistic, measured, or generated by a Borel action of a Polish group have Borel complete countable sections.
135.
Boris Širola 《Algebras and Representation Theory》2008,11(3):233-250
Let \(\mathfrak g\) be a semisimple Lie algebra over a field \(\mathbb K\), \(\text{char}\left( \mathbb{K} \right)=0\), and \(\mathfrak g_1\) a subalgebra reductive in \(\mathfrak g\). Suppose that the restriction of the Killing form B of \(\mathfrak g\) to \(\mathfrak g_1 \times \mathfrak g_1\) is nondegenerate. Consider the following statements: ( 1) For any Cartan subalgebra \(\mathfrak h_1\) of \(\mathfrak g_1\) there is a unique Cartan subalgebra \(\mathfrak h\) of \(\mathfrak g\) containing \(\mathfrak h_1\); ( 2) \(\mathfrak g_1\) is self-normalizing in \(\mathfrak g\); ( 3) The B-orthogonal \(\mathfrak p\) of \(\mathfrak g_1\) in \(\mathfrak g\) is simple as a \(\mathfrak g_1\)-module for the adjoint representation. We give some answers to this natural question: For which pairs \((\mathfrak g,\mathfrak g_1)\) do ( 1), ( 2) or ( 3) hold? We also study how \(\mathfrak p\) in general decomposes as a \(\mathfrak g_1\)-module, and when \(\mathfrak g_1\) is a maximal subalgebra of \(\mathfrak g\). In particular suppose \((\mathfrak g,\sigma )\) is a pair with \(\mathfrak g\) as above and σ its automorphism of order m. Assume that \(\mathbb K\) contains a primitive m-th root of unity. Define \(\mathfrak g_1:=\mathfrak g^{\sigma}\), the fixed point algebra for σ. We prove the following generalization of a well known result for symmetric Lie algebras, i.e., for m=2: (a) \((\mathfrak g,\mathfrak g_1)\) satisfies ( 1); (b) For m prime, \((\mathfrak g,\mathfrak g_1)\) satisfies ( 2). 相似文献
136.
零级拟亚纯映射的充满圆及Borel方向 总被引:1,自引:0,他引:1
罗仕乐 《纯粹数学与应用数学》2008,24(1):54-59
本文利用熊庆来的型函数研究平面上零级K-拟亚纯映射的值分布,给出了零级K-拟亚纯映射在平面上存在充满圆序列及Borel方向的条件. 相似文献
137.
杜兴华 《数学的实践与认识》2010,40(13)
利用多项式的完全判别系统和初等积分法求出了Maccari's方程组的许多新的精确行波解.此方法与其它方法相比更简洁. 相似文献
138.
T. Ramallingam 《Annals of the Institute of Statistical Mathematics》1989,41(4):677-681
The exact probability density function of linear combinations of k=k(n) order statistics selected from the whole order statistics (L-statistic) based on a random sample of size n from the uniform distribution on [0, 1] was derived by Matsunawa (1985, Ann. Inst. Statist. Math., 37, 1–16). As the main expression for the density function given by Matsunawa is not complete for the general situation, we first provide the corrections for this formula. Second, we propose a simple scheme involving symbolic computing for evaluating the corrected version of the density function. The cumulative distribution function and the r-th mean of his L-statistic are also derived. 相似文献
139.
140.
Jibin Li 《Journal of Applied Analysis & Computation》2015,5(1):138-140
This paper considers a long wave-short wave model. It shows that under three different parameter conditions, this system has three types of exact explicit travelling wave solutions. Their parametric representations have been given. 相似文献