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991.
Ibrahim E. Inan 《Applied mathematics and computation》2010,217(4):1294-1299
In this paper, we implemented the exp-function method for the exact solutions of the fifth order KdV equation and modified Burgers equation. By using this scheme, we found some exact solutions of the above-mentioned equations. 相似文献
992.
In this paper, we derive a new family of eighth-order methods for solving simple roots of nonlinear equations by using weight function methods. Per iteration these methods require three evaluations of the function and one evaluation of its first derivative, which implies that the efficiency indexes are 1.682. Numerical comparisons are made to show the performance of the derived methods, as shown in the illustration examples. 相似文献
993.
Mustafa Hasanbulli 《Applied mathematics and computation》2010,215(12):4392-4399
By refining the standard integral averaging technique, we obtain new oscillation criteria for a class of second order nonlinear neutral differential equations of the form
(r(t)(x(t)+p(t)x(t-τ))′)′+q(t)f(x(t),x(σ(t)))=0. 相似文献
994.
Ramesh C. Gupta 《Applied mathematics and computation》2010,216(4):1267-3087
The purpose of this paper is to investigate a very useful application of a certain local dependence function γf(x,y), which was considered recently by Holland and Wang [20]. An interesting property of γf(x,y) is that the underlying joint density f(x,y) is TP2 (that is, totally positive of order 2) if and only if . This gives an elegant way to investigate the TP2 property of any bivariate distribution. For the Saramanov family, the Ali-Mikhail-Haq family of bivariate distributions and the family of bivariate elliptical distributions, we derive the local dependence function and obtain conditions for f(x,y) to be TP2. These families are quite rich and include many other large classes of bivariate distributions as their special cases. Similar conditions are obtained for bivariate distributions with exponential conditionals and bivariate distributions with Pareto conditionals. 相似文献
995.
S.N. Jator 《Applied mathematics and computation》2010,217(8):4036-4046
A three-step seventh order hybrid linear multistep method (HLMM) with three non-step points is proposed for the direct solution of the special second order initial value problems (IVPs) of the form y″ = f(x, y) with an extension to y″ = f(x, y, y′). The main method and additional methods are obtained from the same continuous scheme derived via interpolation and collocation procedures.The stability properties of the methods are discussed by expressing them as a one-step method in higher dimension. The methods are then applied in block form as simultaneous numerical integrators over non-overlapping intervals. Numerical results obtained using the proposed block form reveal that it is highly competitive with existing methods in the literature. 相似文献
996.
S.Z. Németh 《Applied mathematics and computation》2010,217(5):2184-2190
The notion of exceptional family of elements for general order complementarity problems in Banach spaces will be introduced. It will be shown that for general order complementarity problems defined by completely continuous fields the problem has either a solution or an exceptional family of elements. Finite dimensional examples and an application to integral operators will be given. 相似文献
997.
Toshiki Endo 《Topology and its Applications》2010,157(6):1002-1010
We say that a link L1 is an s-major of a link L2 if any diagram of L1 can be transformed into a diagram of L2 by changing some crossings and smoothing some crossings. This relation is a partial ordering on the set of all prime alternating links. We determine this partial order for all prime alternating knots and links with the crossing number less than or equal to six. The proofs are given by graph-theoretic methods. 相似文献
998.
Ka Chun Cheung 《Insurance: Mathematics and Economics》2010,47(2):154-158
When the dependence structure among several risks is unknown, it is common in the actuarial literature to study the worst dependence structure that gives rise to the riskiest aggregate loss. A central result is that the aggregate loss is the riskiest with respect to convex order when the underlying risks are comonotonic. Many proofs were given before. The objective of this article is to present a new proof using the notions of decreasing rearrangement and the majorization theorem, and give clear explanation of the relation between convex order, the theory of majorization and comonotonicity. 相似文献
999.
In this paper, we study the higher‐order semilinear parabolic equation where m, p>1 and $a\,\in\,\mathbb{R}$. For p>1+2m/N, we prove that the global existence of mild solutions for small initial data with respect to some norm. Some of those solutions are proved to be asymptotic self‐similar. Copyright © 2009 John Wiley & Sons, Ltd. 相似文献
1000.
Strong (Weak) Exact Controllability and Strong (Weak) Exact Observability for Quasilinear Hyperbolic Systems 总被引:3,自引:2,他引:1
Numerical approximations of Cahn-Hilliard phase-field model for the two-phase incompressible flows are considered in this paper.Several efficient and energy stable time discretization schemes for the coupled nonlinear Cahn-Hilliard phase-field system for both the matched density case and the variable density case are constructed,and are shown to satisfy discrete energy laws which are analogous to the continuous energy laws. 相似文献