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891.
Suppose that X is a closed, symplectic four-manifold with an anti-symplectic involution σ and its two-dimensional fixed point set. We show that the quotient X/σ admits no almost complex structure if .As a partial converse if X is simply-connected and , then the X/σ admits an almost complex structure.Also we show that the quotient X/σ admits an almost complex structure if X is Kähler and . 相似文献
892.
We derive the Singleton bound for poset codes and define the MDS poset codes as linear codes which attain the Singleton bound.
In this paper, we study the basic properties of MDS poset codes. First, we introduce the concept of I-perfect codes and describe the MDS poset codes in terms of I-perfect codes. Next, we study the weight distribution of an MDS poset code and show that the weight distribution of an MDS
poset code is completely determined. Finally, we prove the duality theorem which states that a linear code C is an MDS -code if and only if is an MDS -code, where is the dual code of C and is the dual poset of
相似文献
893.
V.?A.?Il’inEmail author A.?A.?Kuleshov 《Proceedings of the Steklov Institute of Mathematics》2014,284(1):155-160
In our previous papers, we introduced the notion of a generalized solution to the initial-boundary value problem for the wave equation with a boundary function µ(t) such that the integral ∫ 0 T (T ? t)|µ(t)| p dt exists. Here we prove that this solution is a unique solution to the problem in L p that satisfies the corresponding integral identity. 相似文献
894.
We consider the problem of constructing a common controller stabilizing a finite family of linear dynamic plants of various orders with respect to state. For the solution, we use the method of extension of dynamic order, which permits one to reduce the original problem to a problem of simultaneous stabilization of plants of the same order. We state conditions for the existence of a universal stabilizer for a given finite family of dynamic plants. 相似文献
895.
S. N. Il’in 《Russian Mathematics (Iz VUZ)》2013,57(3):26-31
It is well-known that for modules over rings the Baer injectivity criterion takes place. In this paper we prove that under one additional condition this criterion is also valid for modules over semirings. We prove that a semiring S satisfies the Baer criterion if and only if all injective (with respect to one-sided ideals of S) semimodules satisfy the above condition. We propose a newmethod for constructing semirings satisfying the Baer criterion. 相似文献
896.
We consider stationary linear vector systems with commensurable delays. We obtain sufficient conditions for the reducibility of such systems to canonical form with the extraction of null dynamics. A constructive algorithm for the reduction of a system to that form is presented. We suggest a method for estimating the unknown input for vector delay systems with given accuracy. 相似文献
897.
898.
Yoon Tae Kim 《随机分析与应用》2013,31(5):973-997
Abstract By using the white noise theory for a fractional Brownian sheet, we derive an Itô formula for the generalized functionals for the fractional Brownian sheet with arbitrary Hurst parameters H 1, H 2 ∈ (0,1). As an application, we give the integral representations for two versions of local times of a fractional Brownian sheet, respectively. 相似文献
899.
Yoon Tae Kim 《Journal of Mathematical Analysis and Applications》2009,359(1):106-125
We introduce two types of the Stratonovich stochastic integrals for two-parameter processes, and investigate the relationship of these Stratonovich integrals and various types of Skorohod integrals with respect to a fractional Brownian sheet. By using this relationship, we derive a differentiation formula in the Stratonovich sense for fractional Brownian sheet through Itô formula. Also the relationship between the two types of the Stratonovich integrals will be obtained and used to derive a differentiation formula in the Stratonovich sense. In this case, our proof is based on the repeated applications of differentiation formulas in the Stratonovich form for one-parameter Gaussian processes. 相似文献
900.
A new family of interpolatory stationary subdivision schemes is introduced by using radial basis function interpolation. This
work extends earlier studies on interpolatory stationary subdivision schemes in two aspects. First, it provides a wider class
of interpolatory schemes; each 2L-point interpolatory scheme has the freedom of choosing a degree (say, m) of polynomial reproducing. Depending on the combination (2L,m), the proposed scheme suggests different subdivision rules. Second, the scheme turns out to be a 2L-point interpolatory scheme with a tension parameter. The conditions for convergence and smoothness are also studied.
Dedicated to Prof. Charles A. Micchelli on the occasion of his 60th birthday
Mathematics subject classifications (2000) 41A05, 41A25, 41A30, 65D10, 65D17.
Byung-Gook Lee: This work was done as a part of Information & Communication fundamental Technology Research Program supported
by Ministry of the Information & Communication in Republic of Korea.
Jungho Yoon: Corresponding author. Supported by the Korea Science and Engineering Foundation grant (KOSEF R06-2002-012-01001). 相似文献