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131.
In the present paper,the maximal Lyapunov exponent is investigated for a co-dimension two bifurcation system that is on a three-dimensional central manifold and subjected to parametric excitation by a bounded noise.By using a perturbation method,the expressions of the invariant measure of a one-dimensional phase diffusion process are obtained for three cases,in which different forms of the matrix B,that is included in the noise excitation term,are assumed and then,as a result,all the three kinds of singular boundaries for one-dimensional phase diffusion process are analyzed.Via Monte-Carlo simulation,we find that the analytical expressions of the invariant measures meet well the numerical ones.And furthermore,the P-bifurcation behaviors are investigated for the one-dimensional phase diffusion process.Finally,for the three cases of singular boundaries for one-dimensional phase diffusion process,analytical expressions of the maximal Lyapunov exponent are presented for the stochastic bifurcation system.  相似文献   
132.
本文介绍了进气道实验中动态数据采集及处理方法,研究了滤波器截止频率以及进气道不同流量对动态畸变指数的影响,对在干扰状态下得到的数据以传统方法、统计方法、误差方法进行了分析及处理,并对所得到的实时数据进行了频谱分析。  相似文献   
133.
周期波导中弹性波局部化问题的研究   总被引:3,自引:0,他引:3  
基于弹性波传递矩阵方法,对周期波导中弹性波局部化问题进行了分析研究。根据互易性原理和能量地恒定律,给出了结构弹性波传递矩阵的一般表达式。采用两种求解局部化因子的计算方法,分别计算了谐和与失谐周期波导中的局部化因子,并对其进行了分析讨论。本文对周期波导中波传播与振动局部化的分析方法和计算结果可用于结构的优化设计。  相似文献   
134.
We study thin obstacle problems involving the energy functional with p(x)-growth. We prove higher integrability and Hölder regularity for the gradient of minimizers of the thin obstacle problems under the assumption that the variable exponent p(x) is Hölder continuous.  相似文献   
135.
136.
In this paper, we consider the equations of stationary motion of electrorheological fluids in any dimension n2. We show that the first gradient of local solutions to the system has optimal Lq-regularity with some q>1 with respect to the one of the external force. This is achieved by comparison principle and a good λ-estimate.  相似文献   
137.
We show that if G is a group of exponent 5, and if G satisfiesthe Engel-4 identity [x,y,y,y,y]=1, then G is locally finite.By a result of Traustason, this implies that Engel-4 5-groupsare locally finite. We also show that a group of exponent 5is locally finite if and only if it satsifies the identity This result implies that a group of exponent 5 is locally finiteif its three generator subgroups are finite. 1991 MathematicsSubject Classification: 20D15, 20F45, 20F50.  相似文献   
138.
In the theory of linear elliptic problems with data not belonging to H ?1 two cases can be distinguished. When the right hand side in the equation is a summable function we point out that the a priori estimates can be attained very quickly by symmetrization methods. On the other side, when the datum includes a distributional term, different and subtler tools have to be used. We deal with an equation in the plane, whose right hand side is a functional on a space of Hölder continuous functions with a suitable exponent. We obtain a priori bounds via duality arguments; these, in addition, show Serrin pathological solution (see Serrin in Ann. Scuola Norm. Sup. Pisa 18(3), 385–387, 1964) in its true light.  相似文献   
139.
In this paper we deal with the Hölder regularity up to the boundary of the solutions to a nonhomogeneous Dirichlet problem for second-order discontinuous elliptic systems with nonlinearity q > 1 and with natural growth. The aim of the paper is to clarify that the solutions of the above problem are always global Hölder continuous in the case of the dimension n = q without any kind of regularity assumptions on the coefficients. As a consequence of this sharp result, the singular sets $\Omega_0 \subset \OmegaIn this paper we deal with the H?lder regularity up to the boundary of the solutions to a nonhomogeneous Dirichlet problem for second-order discontinuous elliptic systems with nonlinearity q > 1 and with natural growth. The aim of the paper is to clarify that the solutions of the above problem are always global H?lder continuous in the case of the dimension n = q without any kind of regularity assumptions on the coefficients. As a consequence of this sharp result, the singular sets , are always empty for n = q. Moreover we show that also for 1 < q < 2, but q close enough to 2, the solutions are global H?lder continuous for n = 2.   相似文献   
140.
To optimize the exponent values in protonic and deuteronic Gaussian‐type functions (GTF) by the elimination of translational and rotational motions, we have proposed the new scheme of an analytical gradient formula with respect to the exponent values in the multi‐component molecular orbital scheme, which can take into account the quantum effects of protons and deuterons, under the Hartree‐Fock level of theory. Numerical assessment of H2 and D2 molecules confirms that there is a clear difference between distributions of protonic and deuteronic orbitals following the elimination of translational and rotational motions. In particular, the d‐type GTF in the protonic orbital drastically improves the total energy. © 2007 Wiley Periodicals, Inc. Int J Quantum Chem, 2008  相似文献   
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