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排序方式: 共有3349条查询结果,搜索用时 796 毫秒
111.
A high‐order convection‐bounded scheme is constructed by combining the total variational diminishing constraint and convection boundedness criterion condition in the normalized variable formulation. It employs the Hermite polynomial interpolation to design its characteristic line in the normalized variable diagram. Numerical results of the convection‐dominated problems with smooth or discontinuous initial distributions demonstrate the present scheme possesses high resolution and good robustness. Copyright © 2012 John Wiley & Sons, Ltd. 相似文献
112.
In this article we study variable exponent Sobolev spaces on Riemannian manifolds. The spaces are examined in the case of compact manifolds. Continuous and compact embeddings are discussed. The paper contains an example of the application of the theory to elliptic equations on compact manifolds. 相似文献
113.
Shahpoor Moradi 《理论物理通讯》2009,(7):30-32
For two particles with different spins, we derive the Bell's inequality. The inequality is investigated for two systems combining spin-1 and spin-1/; spin-1/2 and spin-3/2. We show that for these states Bell's inequality is violated. 相似文献
114.
On the existence,uniqueness and stability of solutions for semi-linear generalized elasticity equation with general damping term
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Abita Rahmoune 《数学学报(英文版)》2017,33(11):1549-1564
In this paper, we consider a semi-linear generalized hyperbolic boundary value problem associated to the linear elastic equations with general damping term and nonlinearities of variable exponent type. Under suitable conditions, local and global existence theorems are proved. The uniqueness of the solution have been gotten by eliminating some hypotheses that have been imposed by other authors for different particular problems. We show that any solution with nontrivial initial datum becomes stable. 相似文献
115.
Let X1,X2,... be a sequence of i.i.d. random variables and let X(1),X(2),... be the associatedrecord value sequence. We focus on the asymptotic distributions of sums of records, Tn=∑nk=1X(k), forX1 ∈ LN(γ). In this case, we find that 2 is a strange point for parameter γ. When γ> 2, Tn is asymptoticallynormal, while for 2 >γ> 1, we prove that Tn cannot converge in distribution to any non-degenerate lawthrough common centralizing and normalizing and log Tn is asymptotically normal. 相似文献
116.
X. C. Zeng Y. Chen S. Q. Cheng X. G. Meng Q. Wang 《Journal of Thermal Analysis and Calorimetry》1999,58(2):477-485
A novel method for the determination of rate constants of reactions, the time-variable method, is proposed in this paper. The method needs only three time points (t), peak heights () and pre-peak areas (), obtained from the measured thermoanalytical curve. It does not require the thermokinetic reaction to be completed. It utilizes data-processing on a computer to give the rate constants. Four reaction systems, including a first-order reaction, second-order reactions (with equal concentrations and with unequal concentrations) and a third-order reaction, were studied with this method. The method was validated and its theoretical basis was verified by the experimental results.This revised version was published online in November 2005 with corrections to the Cover Date. 相似文献
117.
分析了磁阀式可控电抗器的结构和工作原理,通过直流控制电流控制铁芯的饱和度来调节电抗器的投入容量,采用可控硅和复杂的可编程逻辑器件(CPLD)为其设计了控制装置,实现了电抗器容量的自动连续调节,具有响应速度快、可靠性高的特点,并在电网无功补偿中得到了较好的应用. 相似文献
118.
We consider a finitecapacity singleserver vacation model with closedown/setup times and Markovian arrival processes (MAP). The queueing model has potential applications in classical IP over ATM or IP switching systems, where the closedown time corresponds to an inactive timer and the setup time to the time delay to set up a switched virtual connection (SVC) by the signaling protocol. The vacation time may be considered as the time period required to release an SVC or as the time during which the server goes to set up other SVCs. By using the supplementary variable technique, we obtain the queue length distribution at an arbitrary instant, the loss probability, the setup rate, as well as the Laplace–Stieltjes transforms of both the virtual and actual waiting time distributions. 相似文献
119.
Susanne C. Brenner. 《Mathematics of Computation》1999,68(225):25-53
We consider nonconforming multigrid methods for symmetric positive definite second and fourth order elliptic boundary value problems which do not have full elliptic regularity. We prove that there is a bound () for the contraction number of the -cycle algorithm which is independent of mesh level, provided that the number of smoothing steps is sufficiently large. We also show that the symmetric variable -cycle algorithm is an optimal preconditioner.
120.
变质量质点的动能定理与软绳问题 总被引:6,自引:0,他引:6
给出变量质点的动能定理和一对反推内力作功的表达式,并由此给出软绳问题的正确解。 相似文献