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131.
模糊数直觉模糊集是直觉模糊集和区间数直觉模糊集的拓展,本文提出了二型直觉模糊数概念,对基于二型直觉模糊信息的多属性决策进行了研究.以结构元理论为基础,给出了二型直觉模糊数的距离公式,然后定义了二型直觉模糊正、负理想点,进而给出了一种基于二型直觉模糊数的多属性决策的步骤.最后通过实例来证明其有效性. 相似文献
132.
本文给出L-fuzzy N-收敛空间的定义,讨论L-fuzzy N-收敛空间范畴(L-fuzzyN-收敛空间和它们之间的连续映射构成的范畴)的若干范畴的性质,并且证明它的一个子范畴同构与L-fuzzy拓扑空间范畴. 相似文献
133.
Let (S, 𝔫) be an s-dimensional regular local ring with s > 2, and let I = (f, g) be an ideal in S generated by a regular sequence f, g of length two. As in [2, 3], we examine the leading form ideal I* of I in the associated graded ring G: = gr𝔫(S). Let μ G (I*) = n ≥ 3, and let {ξ1, ξ2,…, ξ n } be a minimal homogeneous system of generators of I* such that ξ1 = f* and ξ2 = g*, and c i : = deg ξ i ≤ deg ξ i+1: = c i+1 for each i ≤ n ? 1. For m ≤ n, we say that K m : = (ξ1,…, ξ m )G is an ideal generated by part of a minimal homogeneous generating set of I*. Let D i : = GCD(ξ1,…, ξ i ) and d i = deg D i for i with 1 ≤ i ≤ m. Let K m be perfect with ht G K m = 2. We prove that the following are equivalent: 1. deg ξ i+1 = deg ξ i + (d i?1 ? d i ) +1, for all i with 3 ≤ i ≤ m ? 1; 2. deg ξ i+1 ≤ deg ξ i + (d i?1 ? d i ) +1, for all i with 3 ≤ i ≤ m ? 1. Furthermore, if these equivalent conditions hold, then K m = I*. Moreover, if e(G/K m ) = e(G/I*), we prove that K m = I*. We illustrate with several examples in the cases where K m is or is not perfect. 相似文献
134.
For M ∈ R-Mod and τ ∈M-tors, we define the concept of fully τ-bounded module as a generalization of the concept of fully τ-bounded ring. We prove that for a τ-noetherian module M with local τ M -Gabriel correspondence, which is a progenerator of σ[M] and with τ is FIS-invariant, then M is fully τ-bounded. Also, we show that if M is τ-noetherian and fully τ-bounded, then M has local τ M -Gabriel correspondence. 相似文献
135.
A ring R is called a principal ideal ring (PIR), if each ideal of R is a principal ideal. A local ring (R, 𝔪) is an artinian PIR if and only if its maximal ideal 𝔪 is principal and has finite nilpotency index. In this article, we determine the structure of a finite local PIR. 相似文献
136.
E. M. E. Zayed 《Applicable analysis》2013,92(9):905-925
The asymptotic expansions of the trace of the heat kernel for small positive t, where λν are the eigenvalues of the negative Laplacian in Rn (n=2 or 3), are studied for a general annular bounded domain Ω with a smooth inner boundary ?Ω1 and a smooth outer boundary ?Ω2 where a finite number of piecewise smooth Dirichlet, Neumann and Robin boundary conditions on the components Γ j (j=1,…,m) of ?Ω1 and on the components of ?Ω2 are considered such that and and where the coefficients in the Robin boundary conditions are piecewise smooth positive functions. Some applications of Θ (t) for an ideal gas enclosed in the general annular bounded domain Ω are given. 相似文献
137.
《代数通讯》2013,41(6):2553-2573
The first note shows that the integral closure L′ of certain localities L over a local domain R are unmixed and analytically unramified, even when it is not assumed that R has these properties. The second note considers a separably generated extension domain B of a regular domain A, and a sufficient condition is given for a prime ideal p in A to be unramified with respect to B (that is, p B is an intersection of prime ideals and B/P is separably generated over A/p for all P ∈ Ass (B/p B)). Then, assuming that p satisfies this condition, a sufficient condition is given in order that all but finitely many q ∈ S = {q ∈ Spec(A), p ? q and height(q/p) = 1} are unramified with respect to B, and a form of the converse is also considered. The third note shows that if R′ is the integral closure of a semi-local domain R, then I(R) = ∩{R′ p′ ;p′ ∈ Spec(R′) and altitude(R′/p′) = altitude(R′) ? 1} is a quasi-semi-local Krull domain such that: (a) height(N *) = altitude(R) for each maximal ideal N * in I(R); and, (b) I(R) is an H-domain (that is, altitude(I(R)/p *) = altitude(I(R)) ? 1 for all height one p * ∈ Spec(I(R))). Also, K = ∩{R p ; p ∈ Spec(R) and altitude(R/p) = altitude(R) ? 1} is a quasi-semi-local H-domain such that height (N) = altitude(R) for all maximal ideals N in K. 相似文献
138.
Bipan Hazarika 《Applied Mathematics Letters》2012,25(3):466-470
In this article, we introduce the concept of lacunary I-convergent sequence of fuzzy real numbers and study some basic properties. 相似文献
139.
Ekrem Savas 《Applied Mathematics Letters》2012,25(4):733-738
Following the line of recent works of Das et al. (2011) [15] and Savas and Das (2011) [19] we apply the notion of ideals to strong matrix summability, and in this note, we introduce the notion of strong AI-summability with respect to an Orlicz function. We make certain investigations on the classes of sequences arising out of this new summability method. 相似文献
140.
引入了相容半连续Domain、相容强连续Domain的概念,给出了一系列性质,讨论了相容半连续Domain、相容强连续Domain与相容连续Domain间的关系.引入了相容半Scott拓扑,并讨论了其相关性质. 相似文献