共查询到20条相似文献,搜索用时 31 毫秒
1.
2.
《Discrete Mathematics》2022,345(11):113020
3.
4.
Joachim Toft 《Applied and Computational Harmonic Analysis》2019,46(1):154-176
We extend Feichtinger's minimality property on the smallest non-trivial time-frequency shift invariant Banach space, to the quasi-Banach case. Analogous properties are deduced for certain matrix spaces.We use these results to prove that the pseudo-differential operator is a Schatten-q operator from to and r-nuclear operator from to when for suitable p, q and r in . 相似文献
5.
In this paper, we explore some properties of hulls of cyclic serial codes over a finite chain ring and we provide an algorithm for computing all the possible parameters of the Euclidean hulls of that codes. We also establish the average -dimension of the Euclidean hull, where is the residue field of R, as well as we give some results of its relative growth. 相似文献
6.
We construct a class of -additive cyclic codes generated by pairs of polynomials, where p is a prime number. Based on probabilistic arguments, we determine the asymptotic rates and relative distances of this class of codes: the asymptotic Gilbert-Varshamov bound at is greater than and the relative distance of the code is convergent to δ, while the rate is convergent to for and . As a consequence, we prove that there exist numerous asymptotically good -additive cyclic codes. 相似文献
7.
Hai Q. Dinh Xiaoqiang Wang Hongwei Liu Songsak Sriboonchitta 《Discrete Mathematics》2019,342(5):1456-1470
Let be an odd prime, , be positive integers, be nonzero elements of the finite field such that . In this paper, we show that, for any positive integer , the Hamming distances of all repeated-root -constacyclic codes of length can be determined by those of certain simple-root -constacyclic codes of length . Using this result, Hamming distances of all constacyclic codes of length are obtained. As an application, we identify all MDS -constacyclic codes of length . 相似文献
8.
9.
10.
《Discrete Mathematics》2022,345(12):113173
For a graph G, the unraveled ball of radius r centered at a vertex v is the ball of radius r centered at v in the universal cover of G. We obtain a lower bound on the weighted spectral radius of unraveled balls of fixed radius in a graph with positive weights on edges, which is used to present an upper bound on the (where ) smallest normalized Laplacian eigenvalue of irregular graphs under minor assumptions. Moreover, when , the result may be regarded as an Alon–Boppana type bound for a class of irregular graphs. 相似文献
11.
13.
《Discrete Mathematics》2022,345(5):112801
Let G and H be simple graphs. The Ramsey number is the minimum integer N such that any red-blue-coloring of edges of contains either a red copy of G or a blue copy of H. Let denote m vertex-disjoint copies of . A lower bound is that . Burr, Erd?s and Spencer proved that this bound is indeed the Ramsey number for , and . In this paper, we show that this bound is the Ramsey number for and . We also show that this bound is the Ramsey number for and . 相似文献
15.
《Discrete Mathematics》2022,345(12):113158
In 2016, McDiarmid and Yolov gave a tight threshold for the existence of Hamilton cycle in graphs with large minimum degree and without large “bipartite hole”(two disjoint sets of vertices with no edge between them) which extends Dirac's classical Theorem. In detail, an -bipartite-hole in a graph G consists of two disjoint vertex sets S and T with and such that . Let be the maximum integer such that G contains an -bipartite-hole for every pair of nonnegative integers s and t with . Motivated by Bondy's metaconjecture, in this paper, we study the existence of vertex-pancyclicity (every vertex is in a cycle of length i for each and Hamilton-connectivity(any two vertices can be connected through a Hamilton path). Our central theorem is that for any given and sufficiently large n, if G is an n-vertex graph with and , then G is Hamilton-connected and vertex-pancyclic. 相似文献
16.
17.
Xingfei Xiang 《Journal of Mathematical Analysis and Applications》2022,505(2):125518
In bounded convex domains, the regularity of a vector field u with its , in space and the tangential component or the normal component of u over the boundary in space, is established for . As an application, we derive an estimate for solutions to a Maxwell type system with an inhomogeneous boundary condition in convex domains. In contrast to the well-posed region of r in the space for the Maxwell type system in Lipschitz domains given by Kar and Sini (2016) [16], we extend the well-posed region to be optimal. 相似文献
18.
19.
Let C be a chain complex of finitely generated free modules over a commutative Laurent polynomial ring in s indeterminates. Given a group homomorphism we let denote the resulting induced complex over the Laurent polynomial ring in t indeterminates. We prove that the Betti number jump loci, that is, the sets of those homomorphisms p such that , have a surprisingly simple structure. We allow non-unital commutative rings of coefficients, and work with a notion of Betti numbers that generalises both the usual one for integral domains, and the analogous concept involving McCoy ranks in case of unital commutative rings. 相似文献