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931.
E. M. El-Kholy El-Said R. Lashin Salama N. Daoud 《Proceedings Mathematical Sciences》2007,117(3):293-300
In this paper we introduce a new type of folding called equi-Gaussian curvature folding of connected Riemannian 2-manifolds.
We prove that the composition and the cartesian product of such foldings is again an equi-Gaussian curvature folding. In case
of equi-Gaussian curvature foldings, f: M → P
n
, of an orientable surface M onto a polygon P
n
we prove that
and we generalize (iii) for #nT
2. 相似文献
((i)) |
((ii)) |
((iii)) |
932.
A. N. Khisamiev 《Siberian Mathematical Journal》2007,48(6):1115-1126
This is a continuation of [1]. We introduce the concept of a primarily quasiresolvent periodic abelian group and describe primarily quasiresolvent and 1-quasiresolvent periodic abelian groups. We construct an example of a quasiresolvent but not primarily quasiresolvent periodic abelian group. For a direct sum of primary cyclic groups we obtain criteria for a group to be quasiresolvent, 1-quasiresolvent, and resolvent, and establish relations among them. We construct a set S of primes such that the direct sum of some cyclic groups of orders p ∈ S is not a quasiresolvent group. 相似文献
933.
Marcin Bilski 《Mathematische Zeitschrift》2007,256(4):705-716
The aim of this paper is to show that for every locally analytic subset X of C
m
and every there exist a neighborhood V of a in C
m
and a sequence of Nash subsets of V converging to such that X
ν and X satisfy a certain condition for tangency of order ν. Next it is shown that this condition implies that for sufficiently large
ν the multiplicities of X
ν and X at a are equal.
相似文献
934.
It is shown that each critical set in a Latin square of order n > 6 has to have at least empty cells. © 2006 Wiley Periodicals, Inc. J Combin Designs 15: 77–83, 2007 相似文献
935.
James A. Davis Jonathan Jedwab Ken W. Smith 《Proceedings of the American Mathematical Society》2007,135(7):2011-2018
Using only elementary methods, we prove Alquaddoomi and Scholtz's conjecture of 1989, that no Barker array having exists except when .
936.
Let be a surjective operator between two uniform algebras with . We show that if satisfies the peripheral multiplicativity condition for all , where is the peripheral spectrum of , then is an isometric algebra isomorphism from onto . One of the consequences of this result is that any surjective, unital, and multiplicative operator that preserves the peripheral ranges of algebra elements is an isometric algebra isomorphism. We describe also the structure of general, not necessarily unital, surjective and peripherally multiplicative operators between uniform algebras.
937.
Xiu Min REN Kai Man TSANG 《数学学报(英文版)》2007,23(2):265-280
In this paper, it is proved that with at most O(N65/66) exceptions, all even positive integers up to N are expressible in the form p^2 2+p^3 3+p^4 4+p^5 5. This improves a recent result O(N19193/19200+ε) due to C. Bauer. 相似文献
938.
S. Pirzada Merajuddin T. A. Naikoo 《分析论及其应用》2007,23(4):363-374
Let D(U, V, W) be an oriented 3-partite graph with |U|=p, |V|=q and |W|= r. For any vertex x in D(U, V, W), let d x and d-x be the outdegree and indegree of x respectively. Define aui (or simply ai) = q r d ui - d-ui, bvj(or simply bj) = p r d vj - d-vj and Cwk (or simply ck) = p q d wk - d-wk as the scores of ui in U, vj in V and wk in Wrespectively. The set A of distinct scores of the vertices of D(U, V, W) is called its score set. In this paper, we prove that if a1 is a non-negative integer, ai(2≤i≤n - 1) are even positive integers and an is any positive integer, then for n≥3, there exists an oriented 3-partite graph with the score set A = {a1,2∑i=1 ai,…,n∑i=1 ai}, except when A = {0,2,3}. Some more results for score sets in oriented 3-partite graphs are obtained. 相似文献
939.
郭剑寒 《浙江大学学报(理学版)》1993,20(2):141-144
设M是闭的.连通的,光滑的m形,m>2, f映射,P二}xEM[f'(二)=二,对某个;,15r2的周期 本文利用复迭空间的概念推广 相似文献
940.
骆如枫 《浙江大学学报(理学版)》1993,20(4):375-380
本文以胡世华教授建立的自然推理系统为基础,构造了一个弗协调逻辑H.在以H为逻辑的弗协调集合论S_H中,罗素(B.Russell)命题是可证的. 相似文献