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951.
952.
For a torsion-free abelian group , we investigate the problem of determining when is maximal as a ring in the near-ring of all -preserving functions on . We introduce the concept of quasi--locally cyclic groups and determine several properties of these abelian groups.
953.
Abstract In this article, we extend the definition of uniformly starlike functions and uni- formly convex functions on the unit disk to the unit ball in C^n, give the discriminant criterions for them, and get some inequalities for them. 相似文献
954.
唐艳 《数学的实践与认识》2013,43(6)
在具有一致Gateaux可微范数的Banach空间中,建立了一个改进的非扩张映射不动点的粘性逼近方法,并在一定条件下证明了该方法所得到的迭代序列的强收性.本文所得结果扩展并统一了部分文献的结果. 相似文献
955.
A semi‐implicit finite volume model based upon staggered grid is presented for solving shallow water equation. The model employs a time‐splitting scheme that uses a predictor–corrector method for the advection term. The fluxes are calculated based on a Riemann solver in the prediction step and a downwind scheme in the correction step. A simple TVD scheme is employed for shock capturing purposes in which the Minmond limiter is used for flux functions. As a consequence of using staggered grid, an ADI method is adopted for solving the discretized equations for 2‐D problems. Several 1‐D and 2‐D flows have been modeled with satisfactory results when compared with analytical and experimental test cases. The model is also capable of simulating supercritical as well as subcritical flow. Copyright © 2010 John Wiley & Sons, Ltd. 相似文献
956.
957.
A new numerical scheme, namely space–time conservation element and solution element (CE/SE) method, has been used for the solution of the two‐dimensional (2D) dam‐break problem. Distinguishing from the well‐established traditional numerical methods (such as characteristics, finite difference, finite element, and finite‐volume methods), the CE/SE scheme has many non‐traditional features in both concept and methodology: space and time are treated in a unified way, which is the most important characteristic for the CE/SE method; the CEs and SEs are introduced, both local and global flux conservations in space and time rather than space only are enforced; an explicit scheme with a stagger grid is adopted. Furthermore, this scheme is robust and easy to implement. In this paper, an improved CE/SE scheme is extended to solve the 2D shallow water equations with the source terms, which usually plays a critical role in dam‐break flows. To demonstrate the accuracy, robustness and efficiency of the improved CE/SE method, both 1D and 2D dam‐break problems are simulated numerically, and the results are consistent with either the analytical solutions or experimental results. Copyright © 2011 John Wiley & Sons, Ltd. 相似文献
958.
959.
让ψ是蕴含仿紧性的映射保持的闭遗传性质.本文建立了仿紧局部ψ空间的闭映象、某些序列覆盖L映象的内在特征的一般性定理,推广了仿紧局部紧空间映象等的若干结论. 相似文献
960.
Existence for a thermoviscoelastic beam model of brakes 总被引:1,自引:0,他引:1
K. L. Kuttler M. Shillor J. R. Fernndez 《Nonlinear Analysis: Real World Applications》2004,5(5):857-880
The existence of a weak solution to a model for the dynamic thermomechanical behavior of a viscoelastic beam, which is in frictional contact with a rigid rotating wheel, is established. The model describes a simple braking system in which a rotating wheel comes to a stop as a result of the frictional traction generated by the beam. The classical model consists of a system of coupled equations for the beam temperature and displacement, the wear of the beam's contacting end, the wheel temperature and its angular velocity. The weak formulation is an abstract differential inclusion involving set-valued pseudomonotone operators, The existence is proved by using recent results for such operators. Uniqueness is shown to hold when the wheel's angular velocity and temperature are known. 相似文献