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11.
宋显花 《数学的实践与认识》2021,(3):182-185
设B(X)是维数大于等于3的复Banach空间X上有界线性算子全体构成的代数.设A∈B(X),若Ax=x,则称x∈X是算子A的固定点.Fix(A)表示A的所有固定点的集合.本文刻画了B(X)上保持算子的Jordan积的固定点的满射. 相似文献
12.
The star products in symbolic dynamics, as effective algebraic operations for describing self-similar bifurcation structure in classical dynamical systems, are found to have either associativity or non-associativity. In this Letter, non-associative star products in trimodal iterative dynamical systems are considered. As the left and right operations have different effects, right-associative star products break the conventional Feigenbaum's metric universality. Through high precision parallel computation, it is found that period-p-tupling bifurcation processes described by right-associative star products exhibit a superconvergent universality of double exponential form. 相似文献
13.
Protein kinase C (PKC) plays a key role in neurotransmission in the central nervous system, and targeting PKC domain is considered as a strategy to modulate the anaesthetic effects. In this study, we described a synthetic pipeline to perform high-throughput virtual screening against a large library of 3D structural natural products released recently in order to discover those potential PKC modulators. A total of 100 natural products with top scores were raised, from which 12 promising candidates were tested to determine their inhibitory potencies against PKC. As might be expected, the promiscuous kinase inhibitor staurosporine showed a high PKC inhibitory activity (IC50 = 64 nM), and other two tested compounds, i.e. fisetin and tetrahydropapaverine, were also highly potent with their activities at nanomolar level (IC50 = 370 and 190, respectively). 相似文献
14.
Toll convexity is a variation of the so-called interval convexity. A tolled walk between two non-adjacent vertices and in a graph is a walk, in which is adjacent only to the second vertex of and is adjacent only to the second-to-last vertex of . A toll interval between is a set . A set is toll convex, if for all . A toll closure of a set is the union of toll intervals between all pairs of vertices from . The size of a smallest set whose toll closure is the whole vertex set is called a toll number of a graph , . The first part of the paper reinvestigates the characterization of convex sets in the Cartesian product of two graphs. It is proved that the toll number of the Cartesian product of two graphs equals 2. In the second part, the toll number of the lexicographic product of two graphs is studied. It is shown that if is not isomorphic to a complete graph, . We give some necessary and sufficient conditions for . Moreover, if has at least two extreme vertices, a complete characterization is given. Furthermore, graphs with are characterized. Finally, the formula for is given — it is described in terms of the so-called toll-dominating triples or, if is complete, toll-dominating pairs. 相似文献
15.
Itamar Stein 《代数通讯》2017,45(5):2105-2126
We give a new proof for the Littlewood-Richardson rule for the wreath product F?Sn where F is a finite group. Our proof does not use symmetric functions but use more elementary representation theoretic tools. We also derive a branching rule for inducing the natural embedding of F?Sn to F?Sn+1. We then apply the generalized Littlewood-Richardson rule for computing the ordinary quiver of the category F?FIn where FIn is the category of all injective functions between subsets of an n-element set. 相似文献
16.
William O’Donovan 《代数通讯》2017,45(3):1314-1322
17.
18.
Ratikanta Behera 《Linear and Multilinear Algebra》2017,65(8):1662-1682
The notion of the Moore–Penrose inverse of tensors with the Einstein product was introduced, very recently. In this paper, we further elaborate on this theory by producing a few characterizations of different generalized inverses of tensors. A new method to compute the Moore–Penrose inverse of tensors is proposed. Reverse order laws for several generalized inverses of tensors are also presented. In addition to these, we discuss general solutions of multilinear systems of tensors using such theory. 相似文献
19.
Exact and approximation product solutions form of heat equation with nonlocal boundary conditions using Ritz–Galerkin method with Bernoulli polynomials basis 下载免费PDF全文
Z. Barikbin E. Keshavarz Hedayati 《Numerical Methods for Partial Differential Equations》2017,33(4):1143-1158
In this article, a new method is introduced for finding the exact solution of the product form of parabolic equation with nonlocal boundary conditions. Approximation solution of the present problem is implemented by the Ritz–Galerkin method in Bernoulli polynomials basis. The properties of Bernoulli polynomials are first presented, then Ritz–Galerkin method in Bernoulli polynomials is used to reduce the given differential equation to the solution of algebraic equations. Illustrative examples are included to demonstrate the validity and applicability of the techniques presented in this article for finding the exact and approximation solutions. © 2016 Wiley Periodicals, Inc. Numer Methods Partial Differential Eq 33: 1143–1158, 2017 相似文献
20.
两类图的(d,1)-全标号 总被引:1,自引:0,他引:1
主要讨论了W_n与C_m的笛卡尔积和均衡完全r-部图K_r(n)的(d,1)-全标号,并得出了(d,1)-全数λ_d~T(W_n□C_m)和λ_d~T(K_(r(n)))的确切值. 相似文献