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131.
利用拓扑度计算,研究了一类超线性奇异Neumann边值问题非平凡解的存在性,其中非线性项可变号且下方无界. 相似文献
132.
In this paper, we are concerned with the existence of solution to a boundary value problem of nonlinear fractional differential equation at resonance. By means of the coincidence degree theory, the existence of solution is obtained. 相似文献
133.
In this paper the authors generalize the classic random bipartite graph model, and define a model of the random bipartite multigraphs as follows:let m = m(n) be a positive integer-valued function on n and ζ(n,m;{pk}) the probability space consisting of all the labeled bipartite multigraphs with two vertex sets A ={a1,a2,...,an} and B = {b1,b2,...,bm}, in which the numbers tai,bj of the edges between any two vertices ai∈A and bj∈ B are identically distributed independent random variables with distribution P{tai,bj=k}=pk,k=0,1,2,...,where pk ≥0 and ∞Σk=0 pk=1. They obtain that Xc,d,A, the number of vertices in A with degree between c and d of Gn,m∈ζ(n, m;{pk}) has asymptotically Poisson distribution, and answer the following two questions about the space ζ(n,m;{pk}) with {pk} having geometric distribution, binomial distribution and Poisson distribution, respectively. Under which condition for {pk} can there be a function D(n) such that almost every random multigraph Gn,m∈ζ(n,m;{pk}) has maximum degree D(n)in A? under which condition for {pk} has almost every multigraph G(n,m)∈ζ(n,m;{pk}) a unique vertex of maximum degree in A? 相似文献
134.
结合高职院校"双师型"教师实训教学的关键行动,构建了高职院校"双师型"教师实训教学绩效评价的指标体系,并结合实例将隶属度转换算法应用于具体的"双师型"教师实训教学绩效评价之中. 相似文献
135.
Let G be a finite group, Irr1(G) be the set of nonlinear irreducible characters of G and cd1(G) the set of degrees of the characters in Irr1(G). A group G is said to be a D2-group if|cd1(G)|=|Irr1(G)|-2. In this paper, we give a complete classification of solvable D2-groups. 相似文献
136.
John Engbers 《Journal of Graph Theory》2017,85(4):780-787
For graphs G and H , an H‐coloring of G is a map from the vertices of G to the vertices of H that preserves edge adjacency. We consider the following extremal enumerative question: for a given H , which connected n‐vertex graph with minimum degree δ maximizes the number of H‐colorings? We show that for nonregular H and sufficiently large n , the complete bipartite graph is the unique maximizer. As a corollary, for nonregular H and sufficiently large n the graph is the unique k‐connected graph that maximizes the number of H‐colorings among all k‐connected graphs. Finally, we show that this conclusion does not hold for all regular H by exhibiting a connected n‐vertex graph with minimum degree δ that has more ‐colorings (for sufficiently large q and n ) than . 相似文献
137.
Johannes H. Hattingh 《Discrete Applied Mathematics》2009,157(13):2846-2858
Let G=(V,E) be a graph. A set S⊆V is a restrained dominating set if every vertex in V−S is adjacent to a vertex in S and to a vertex in V−S. The restrained domination number of G, denoted γr(G), is the smallest cardinality of a restrained dominating set of G. We will show that if G is a connected graph of order n and minimum degree δ and not isomorphic to one of nine exceptional graphs, then . 相似文献
138.
Ramesh Prasad Panda 《代数通讯》2018,46(7):3182-3197
In this paper, the minimum degree of power graphs of certain cyclic groups, abelian p-groups, dihedral groups and dicyclic groups are obtained. It is ascertained that the edge-connectivity and minimum degree of power graphs are equal, and consequently, the minimum disconnecting sets of power graphs of the aforementioned groups are determined. In order to investigate the equality of connectivity and minimum degree of power graphs, certain necessary conditions for finite groups and a necessary and su?cient condition for finite cyclic groups are obtained. Moreover, the equality is discussed for the power graphs of abelian p-groups, dihedral groups and dicyclic groups. 相似文献
139.
In this paper, we firstly analyze some properties of the linear difference operator $[Ax](t)=x(t)-C(t)x(t-\tau),$ where $C(t)$ is a $n\times n$ matrix function, and then using Mawhin''s continuation theorem, a first-order neutral functional differential system is studied. Some new results on the existence and stability of periodic solutions are obtained. The results are related to the deviating arguments $\tau$ and $\mu$. Meanwhile, the approaches to estimate a $prior$ bounds of periodic solutions are different from the corresponding ones of the known literature. 相似文献
140.
基于模糊环境给出多值不确定型直觉模糊集的概念,定义了集合的交、并、包含等基本运算性质。通过刻画集合间的相似程度,提出八个新的相似度公式。最后将相似度应用于识别决策,说明公式的实用性和有效性。 相似文献