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971.
The problem of applying some approaches to approximate solutions and the asymmetry of closed phase trajectories in some domain of parameters are examined__________Translated from Prikladnaya Mekhanika, Vol. 41, No. 2, pp. 81–90, February 2005. 相似文献
972.
For a convex set-valued map between p-normed (0 < p ≤ 1) spaces, we give a criterion for its inverse to be locally Lipschitz of order p. From this we obtain the Robinson-Ursescu Theorem in p-normed spaces and the open mapping and closed graph theorems for closed convex set-valued maps. 相似文献
973.
Let RS be an extension of integral domains. If each intermediate ring in this extension is integrally closed in S, then (R,S) is called a normal pair. We investigate in this work the set of intermediate rings in such ring extensions. We establish several results and equations concerning the cardinality of the set of intermediate rings. In particular, we give a way to compute the number of intermediate rings in normal pairs with only finitely many intermediate rings. 相似文献
974.
乘积FC-空间中广义混合向量拟平衡问题系统 总被引:1,自引:0,他引:1
本文在乘积FC-空间中引入并研究一类新的广义混合向量拟平衡问题系统,利用极大元定理,得到了关于广义混合向量拟平衡问题系统解的一些存在性定理,改进和推广了前人已有的某些结果. 相似文献
975.
V. A. Gutnikov V. Yu. Kiryakin I. K. Lifanov A. V. Setukha S. L. Stavtsev 《Computational Mathematics and Mathematical Physics》2007,47(12):2002-2013
A mathematical model of sound propagation from a noise source in urban areas is constructed. The exterior Neumann problem for the scalar Helmholtz equation is reduced to a system of hypersingular integral equations. A numerical method for solving the system of integral equations is described. The convergence of the quadrature formulas underlying the numerical method is estimated. Numerical results are presented for particular applications. 相似文献
976.
设Hi是实或复数域上无限维完备的不定度规空间,Ai是B(Hi)中由单位元I和一个理想生成的子代数,其中B(Hi)表示Hi上所有有界线性算子构成的代数,i=1,2.本文刻画了从A1到A2上双边保不定半正交性的可加满射Ф,即对任意T,S∈A1,T S=0(=)Ф(T) Ф(S)=0.主要结果表明,这样的Ф具有形式Ф(T)=UTV对任意的T∈A1成立,这里U,V是有界线性或共轭线性可逆算子且U U=cI,c是非零实数. 相似文献
977.
半经典闭合轨道理论已经成功地计算了在外加磁场和平行电磁场中的里德堡原子的回归谱.但对于垂直电磁场中的里德堡原子,理论和计算都变得更为复杂.本文把闭合轨道理论推广到三维情况,采用 B.Hüpper的模型势计算了ε=-0.03,主量子数n≈ 40,m=0下He原子在垂直电磁场中的光吸收谱和回归谱,并和H原子在垂直电磁场中的回归谱作比较,突出了实散射的贡献.计算中应用了离子实散射的分区自洽迭代方法,并考虑到轨道的多次重复和离子实的多次散射效应.这是对闭合轨道理论的验证和进一步推广. 相似文献
978.
979.
A.G. Hitchcock 《Topology and its Applications》1982,14(3):267-281
Recent development of the theory of general topological vector spaces (without local convexity, hence without duality theory), as in [1], has exposed more of the essential (distinctly topological) nature of a good deal of the locally convex theory, resulting in a remarkably high survival rate of theorems, with (it is claimed) greater simplicity and elegance of proofs. This is especially true of the closed graph theorem. Associated concepts, such as barrelledness and the various kinds of completeness, can be described and related in a manner which demands extension to uniform spaces and beyond. In the setting of categories and functors, we believe these ideas acquire an elegance and unity which considerably widens their scope while shedding light on their homeground in functional analysis. The aim of this paper, which takes a much broader perspective than Pelletier [10], is to distill some of this categorical essence, and to point out new problems, both topological and categorical, which present themselves along the way. 相似文献
980.
We give several applications of a recent theorem of the second author, which solved a conjecture of the first author with Hay and Neal, concerning contractive approximate identities; and another of Hay from the theory of noncommutative peak sets, thereby putting the latter theory on a much firmer foundation. From this theorem it emerges there is a surprising amount of positivity present in any operator algebras with contractive approximate identity. We exploit this to generalize several results previously available only for C?-algebras, and we give many other applications. 相似文献