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971.
研究了具有热储备的并行可修复系统中,其稳定解的最优控制问题,并给出了其最优解的存在唯一性. 相似文献
972.
利用不动点指数理论研究奇异二阶周期边值问题.在有关其线性算子方程对应的第一特征值的条件下得到边值问题正解的存在性,推广和改进了最近文献的结果. 相似文献
973.
Jong Uhn Kim 《Transactions of the American Mathematical Society》2008,360(2):575-607
We prove the existence and uniqueness of solutions to the initial boundary value problem for a one-dimensional wave equation with unilateral boundary conditions and random noise. We also establish the existence of an invariant measure.
974.
We study the existence of non-collision periodic solutions for second order singular dynamical systems. The repulsive case and the attractive case are dealt with using a unified topological approach. The proof is based on a well-known fixed point theorem for completely continuous operators, involving a new type of cone. We do not need to consider so-called strong force conditions. Moreover, for the repulsive case, the critical case can be covered. Recent results in the literature, even in the scalar case, are complemented, generalized and improved. 相似文献
975.
The spatial structure of a Bose-Einstein Condensate (BEC) loaded into an optical lattice potential is investigated. We suggest
a method for generating chaos in BEC by modulating periodic signals to convert the regular states into chaotic states. The
maximal Lyapunov exponent is calculated as a function of modulation intensity and modulation frequency respectively, and the
chaotic orbits associated with the positive Lyapunov exponents.
相似文献
976.
In this paper, homotopy perturbation method (HPM) and variational iteration method (VIM) are applied to solve nonlinear oscillator
differential equations. Illustrative examples reveal that these methods are very effective and convenient for solving nonlinear
differential equations. Moreover, the methods do not require linearization or small perturbation. Comparisons are also made
between the exact solutions and the results of the homotopy perturbation method and variational iteration method in order
to prove the precision of the results obtained from both methods mentioned. 相似文献
977.
This paper concerns with properties of solutions of a nonlinear diffusion problem in non-divergence form.By constructing proper test functions,it is proved that solutions of the problem possess the property of localization. 相似文献
978.
向量优化问题有效解的稳定性 总被引:1,自引:0,他引:1
运用标量化的方法,通过锥正定真有效解的上半连续性讨论了无限维赋范空间中锥有效解的部分上半连续性,证明了锥有效解的通有稳定性.在此基础上,进一步证明,在Baire纲的意义下,绝大多数的向量优化问题至少存在一个锥正定真有效解是本质的有效解,换句话说,绝大多数的向量优化问题锥有效解是几乎下半连续的. 相似文献
979.
By using the theory of coincidence degree,we study a kind of periodic solutions to second order differential equation with a deviating argument such as x"(t) f(x'(t)) h(x(t))x'(t) g(x(t-τ(t)))=p(t),some sufficient conditions on the existence of periodic solutions are obtained. 相似文献
980.
Aditya Kaushik 《Numerical Methods for Partial Differential Equations》2008,24(1):217-238
This paper deals with the construction of a nonstandard numerical method to compute the travelling wave solutions of nonlinear reaction diffusion equations at high wave speeds. Related general properties are studied using the perturbation approximation. At high wave speed the perturbation parameter approaches to zero and the problem exhibits a multiscale character. That is, there are thin layers where the solution varies rapidly, while away from these layers the solution behaves regularly and varies slowly. Most of the conventional methods fail to capture this layer behavior. Thus, the quest for some new numerical techniques that may handle the travelling wave solutions at high wave speeds earns relevance. In this paper, one such parameter robust nonstandard numerical scheme is constructed, in the sense that its numerical solution converges in the maximum norm to the exact solution uniformly well for all finite wave speeds. To overcome the difficulty due to the nonlinearity, the problem is linearized using the quasilinearization process followed by nonstandard finite difference discretization. An extensive amount of analysis is carried out which uses a suitable decomposition of the error into smooth and singular component and a comparison principle combined with appropriate barrier functions. The error estimates are obtained, which ensures uniform convergence of the method. A set of numerical experiment is carried out in support of the predicted theory that validates computationally the theoretical results. © 2007 Wiley Periodicals, Inc. Numer Methods Partial Differential Eq, 2007 相似文献