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991.
We show that every nonempty compact and convex space M of probability Radon measures either contains a measure which has ‘small’ local character in M or else M contains a measure of ‘large’ Maharam type. Such a dichotomy is related to several results on Radon measures on compact spaces and to some properties of Banach spaces of continuous functions. 相似文献
992.
993.
In this paper, we establish Ekeland’s variational principle and an equilibrium version of Ekeland’s variational principle for vectorial multivalued mappings in the setting of separated, sequentially complete uniform spaces. Our approaches and results are different from those in Chen et al. (2008), Hamel (2005), and Lin and Chuang (2010) [13], [14] and [15]. As applications of our results, we study vectorial Caristi’s fixed point theorems and Takahashi’s nonconvex minimization theorems for multivalued mappings and their equivalent forms in a separated, sequentially complete uniform space. We also apply our results to study maximal element theorems, which are unified methods of several variational inclusion problems. Our results contain many known results in the literature Fang (1996) [21], and will have many applications in nonlinear analysis. 相似文献
994.
Ahmad T. Ali 《Journal of Computational and Applied Mathematics》2011,235(14):4117-4127
In this work, a new generalized Jacobi elliptic function rational expansion method is based upon twenty-four Jacobi elliptic functions and eight double periodic Weierstrass elliptic functions, which solve the elliptic equation ?′2=r+p?2+q?4, is described. As a consequence abundant new Jacobi-Weierstrass double periodic elliptic functions solutions for (3+1)-dimensional Kadmtsev-Petviashvili (KP) equation are obtained by using this method. We show that the new method can be also used to solve other nonlinear partial differential equations (NPDEs) in mathematical physics. 相似文献
995.
Xia CuiGuang-wei Yuan Jing-yan Yue 《Journal of Computational and Applied Mathematics》2011,236(2):253-264
A nonlinear iteration method named the Picard-Newton iteration is studied for a two-dimensional nonlinear coupled parabolic-hyperbolic system. It serves as an efficient method to solve a nonlinear discrete scheme with second spatial and temporal accuracy. The nonlinear iteration scheme is constructed with a linearization-discretization approach through discretizing the linearized systems of the original nonlinear partial differential equations. It can be viewed as an improved Picard iteration, and can accelerate convergence over the standard Picard iteration. Moreover, the discretization with second-order accuracy in both spatial and temporal variants is introduced to get the Picard-Newton iteration scheme. By using the energy estimate and inductive hypothesis reasoning, the difficulties arising from the nonlinearity and the coupling of different equation types are overcome. It follows that the rigorous theoretical analysis on the approximation of the solution of the Picard-Newton iteration scheme to the solution of the original continuous problem is obtained, which is different from the traditional error estimate that usually estimates the error between the solution of the nonlinear discrete scheme and the solution of the original problem. Moreover, such approximation is independent of the iteration number. Numerical experiments verify the theoretical result, and show that the Picard-Newton iteration scheme with second-order spatial and temporal accuracy is more accurate and efficient than that of first-order temporal accuracy. 相似文献
996.
Diego Conti 《Differential Geometry and its Applications》2011,29(4):493-506
We introduce obstructions to the existence of a calibrated G2-structure on a Lie algebra g of dimension seven, not necessarily nilpotent. In particular, we prove that if there is a Lie algebra epimorphism from g to a six-dimensional Lie algebra h with kernel contained in the center of g, then h has a symplectic form. As a consequence, we obtain a classification of the nilpotent Lie algebras that admit a calibrated G2-structure. 相似文献
997.
1前言作者建立了一个新型的符合临界重整化群理论的跨接状态方程,能够描述物质的整个区域热力性质山。鉴于R134a是R12的新的主要替代制冷剂,为了计算其整个区域的热力性质,本文将新跨接状态方程应用于R134a,以便提供一个能在整个区域计算R134a热力性质的状态方程。2新跨接状态方程作者建立了以下型式的新跨接状态方程l‘]:上式中,西方一r一IDZ户一p巾c;,一DI—TD;T—To/T;产为密度;pc为临界密度;T为温度;To为临界温度;矿对比过余Helmholtz自由能;A是Helmholtz自由能。新函数中,a。一30,a,一10;0—0.325和西一… 相似文献
998.
α,α'-二氧代烯酮环二硫代缩醛的NMR研究 总被引:1,自引:3,他引:1
报道了7种新的α,α'-二氧代烯酮环二硫代缩醛化合物的NMR谱.应用1H、13C NMR谱等确定了这7种新化合物的分子结构,并对全部谱峰进行了归属,初步探讨了分子结构对化学位移的影响. 相似文献
999.
半线性Sobolev方程的H~1-Galerkin混合有限元方法 总被引:1,自引:0,他引:1
利用H~1-Galerkin混合有限元方法研究了一维半线性Sobolev方程,得到了半离散解的最优阶误差估计,优点是不需验证LBB相容性条件. 相似文献
1000.
H1-Galerkin mixed methods are proposed for viscoelasticity wave equation.Depending on the physical quantities of interest,two methods are discussed.The optimal error estimates and the proof of the existence and uniqueness of semidiscrete solutions are derived for problems in one space dimension.And the methods don't require the LBB condition. 相似文献