Bipolar single-valued neutrosophic models are the generalization of bipolar fuzzy models. We first introduce the concept of bipolar single-valued neutrosophic competition graphs. We then, discuss some important propos...Bipolar single-valued neutrosophic models are the generalization of bipolar fuzzy models. We first introduce the concept of bipolar single-valued neutrosophic competition graphs. We then, discuss some important propositions related to bipolar single-valued neutrosophic competition graphs. We define bipolar single-valued neutrosophic economic competition graphs and m-step bipolar single-valued neutrosophic economic competition graphs. Further, we describe applications of bipolar single-valued neutrosophic competition graphs in organizational designations and brands competition. Finally, we present our improved methods by algorithms.展开更多
Given a digraph D =（V, A）, the competition graph G of D, denoted by C（D）, has the same set of vertices as D and an edge between vertices x and y if and only if N;（x）∩N;（y）≠Ф. In this paper, we investigate t...Given a digraph D =（V, A）, the competition graph G of D, denoted by C（D）, has the same set of vertices as D and an edge between vertices x and y if and only if N;（x）∩N;（y）≠Ф. In this paper, we investigate the competition graphs of round digraphs and give a necessary and sufficient condition for these graphs to be hamiltonian.展开更多
For any graph?G,?G?together with sufficiently many isolated vertices is the competition graph of some acyclic digraph. The competition number?k(G)?of a graph?G?is defined to be the smallest number of such isolated ver...For any graph?G,?G?together with sufficiently many isolated vertices is the competition graph of some acyclic digraph. The competition number?k(G)?of a graph?G?is defined to be the smallest number of such isolated vertices. In general, it is hard to compute the competition number?k(G)?for a graph?G?and chara-cterizing a graph by its competition number has been one of important research problems in the study of competition graphs. A 2-connected planar graph?G?with minimum degree at least 3 is a pseudo-Halin graph if deleting the edges on the boundary of a single face?f0?yields a tree. It is a Halin graph if the vertices of?f0?all have degree 3 in?G. In this paper, we compute the competition numbers of a kind of pseudo-Halin graphs.展开更多
As a generalization of the scrambling index and the exponent,m-competition index has been widely applied to stochastic matrices,food webs and memoryless communication systems in recent years. For a positive integer m,...As a generalization of the scrambling index and the exponent,m-competition index has been widely applied to stochastic matrices,food webs and memoryless communication systems in recent years. For a positive integer m,where 1 ≤ m ≤ n,the mcompetition index( generalized competition index) of a primitive digraph D of order n is the smallest positive integer k such that for every pair of vertices x and y,there exist m distinct vertices v_1,v_2,…,v_m such that there exist walks of length k from x to v_i and from y to v_i for 1 ≤ i ≤ m. By analyzing the structure of θ-graphs( theta graphs) and using enumeration investigation methods,the mcompetition indices of primitive θ-graphs are studied and an upper bound is provided. Moreover, some corresponding extremal θ-graphs are characterized.展开更多
It is hard to compute the competition number for a graph in general and characterizing a graph by its competition number has been one of important research problems in the study of competition graphs. Sano pointed out...It is hard to compute the competition number for a graph in general and characterizing a graph by its competition number has been one of important research problems in the study of competition graphs. Sano pointed out that it would be interesting to compute the competition numbers of some triangulations of a sphere as he got the exact value of the competition numbers of regular polyhedra. In this paper, we study the competition numbers of several kinds of triangulations of a sphere, and get the exact values of the competition numbers of a 24-hedron obtained from a hexahedron by adding a vertex in each face of the hexahedron and joining the vertex added in a face with the four vertices of the face, a class of dodecahedra constructed from a hexahedron by adding a diagonal in each face of the hexahedron, and a triangulation of a sphere with 3n (n≥2) vertices.展开更多
As a key technique in hyperspectral image pre-processing,dimensionality reduction has received a lot of attention.However,most of the graph-based dimensionality reduction methods only consider a single structure in th...As a key technique in hyperspectral image pre-processing,dimensionality reduction has received a lot of attention.However,most of the graph-based dimensionality reduction methods only consider a single structure in the data and ignore the interfusion of multiple structures.In this paper,we propose two methods for combining intra-class competition for locally preserved graphs by constructing a new dictionary containing neighbourhood information.These two methods explore local information into the collaborative graph through competing constraints,thus effectively improving the overcrowded distribution of intra-class coefficients in the collaborative graph and enhancing the discriminative power of the algorithm.By classifying four benchmark hyperspectral data,the proposed methods are proved to be superior to several advanced algorithms,even under small-sample-size conditions.展开更多
There exist two or more competing products in viral marketing, and the companies can exploit the social interactions of users to propagate the awareness of products. In this paper, we focus on selecting seeds for maxi...There exist two or more competing products in viral marketing, and the companies can exploit the social interactions of users to propagate the awareness of products. In this paper, we focus on selecting seeds for maximizing the competitive influence spread in social networks. First, we establish the possible graphs based on the propagation probability of edges, and then we use the competitive influence spread model (CISM) to model the competitive spread under the possible graph. Further, we consider the objective function of selecting k seeds of one product under the CISM when the seeds of another product have been known, which is monotone and submodular, and thus we use the CELF (cost-effective lazy forward) algorithm to accelerate the greedy algorithm that can approximate the optimal with 1 ? 1/e. Experimental results verify the feasibility and effectiveness of our method.展开更多
为整体审视我国体育后备人才研究的发展动态、前沿热点与演进历程,以期为我国体育后备人才研究提供理论依据与参考,使得研究能与实践深度融合,在体育强国的时代背景下实现应用价值最大化。本文采用Cite Space V软件与文献计量方法对1986...为整体审视我国体育后备人才研究的发展动态、前沿热点与演进历程,以期为我国体育后备人才研究提供理论依据与参考,使得研究能与实践深度融合,在体育强国的时代背景下实现应用价值最大化。本文采用Cite Space V软件与文献计量方法对1986-2021年CNKI学术期刊数据库收录的1496篇体育后备人才研究文献进行研究,结果表明:我国体育后备人才年发文量呈波浪式增长,分为孕育萌芽阶段、快速发展阶段与稳步增长阶段三个阶段,学术关注度呈现“前低后高”;合作网络之间较少而松散,仅形成了两个较大的核心合作网络群;研究热点主要集中于体育后备人才宏观研究、体育后备人才培养与竞技体育等方面;主题研究演进经历了4个时期:开篇布局时期(1986-2001年)、体教结合时期(2002-2008年)、后奥运会时期(2009-2019年)与体教融合时期(2020至今)。展开更多
Let D be a digraph.The competition graph of D is the graph having the same vertex set with D and having an edge joining two different vertices if and only if they have at least one common out-neighbor in D.The phyloge...Let D be a digraph.The competition graph of D is the graph having the same vertex set with D and having an edge joining two different vertices if and only if they have at least one common out-neighbor in D.The phylogeny graph of D is the competition graph of the digraph constructed from D by adding loops at all vertices.The competition/phylogeny number of a graph is the least number of vertices to be added to make the graph a competition/phylogeny graph of an acyclic digraph.In this paper,we show that for any integer k there is a connected graph such that its phylogeny number minus its competition number is greater than k.We get similar results for hypergraphs.展开更多
文摘Bipolar single-valued neutrosophic models are the generalization of bipolar fuzzy models. We first introduce the concept of bipolar single-valued neutrosophic competition graphs. We then, discuss some important propositions related to bipolar single-valued neutrosophic competition graphs. We define bipolar single-valued neutrosophic economic competition graphs and m-step bipolar single-valued neutrosophic economic competition graphs. Further, we describe applications of bipolar single-valued neutrosophic competition graphs in organizational designations and brands competition. Finally, we present our improved methods by algorithms.
基金Supported by NSFC(11401353)TYAL of ShanxiNatural Science Foundation of Shanxi Province(2016011005)
文摘Given a digraph D =（V, A）, the competition graph G of D, denoted by C（D）, has the same set of vertices as D and an edge between vertices x and y if and only if N;（x）∩N;（y）≠Ф. In this paper, we investigate the competition graphs of round digraphs and give a necessary and sufficient condition for these graphs to be hamiltonian.
文摘For any graph?G,?G?together with sufficiently many isolated vertices is the competition graph of some acyclic digraph. The competition number?k(G)?of a graph?G?is defined to be the smallest number of such isolated vertices. In general, it is hard to compute the competition number?k(G)?for a graph?G?and chara-cterizing a graph by its competition number has been one of important research problems in the study of competition graphs. A 2-connected planar graph?G?with minimum degree at least 3 is a pseudo-Halin graph if deleting the edges on the boundary of a single face?f0?yields a tree. It is a Halin graph if the vertices of?f0?all have degree 3 in?G. In this paper, we compute the competition numbers of a kind of pseudo-Halin graphs.
基金Shanxi Scholarship Council of China(No.2012-070)Foundation of North University of China(No.2013-12-1)
文摘As a generalization of the scrambling index and the exponent,m-competition index has been widely applied to stochastic matrices,food webs and memoryless communication systems in recent years. For a positive integer m,where 1 ≤ m ≤ n,the mcompetition index( generalized competition index) of a primitive digraph D of order n is the smallest positive integer k such that for every pair of vertices x and y,there exist m distinct vertices v_1,v_2,…,v_m such that there exist walks of length k from x to v_i and from y to v_i for 1 ≤ i ≤ m. By analyzing the structure of θ-graphs( theta graphs) and using enumeration investigation methods,the mcompetition indices of primitive θ-graphs are studied and an upper bound is provided. Moreover, some corresponding extremal θ-graphs are characterized.
文摘It is hard to compute the competition number for a graph in general and characterizing a graph by its competition number has been one of important research problems in the study of competition graphs. Sano pointed out that it would be interesting to compute the competition numbers of some triangulations of a sphere as he got the exact value of the competition numbers of regular polyhedra. In this paper, we study the competition numbers of several kinds of triangulations of a sphere, and get the exact values of the competition numbers of a 24-hedron obtained from a hexahedron by adding a vertex in each face of the hexahedron and joining the vertex added in a face with the four vertices of the face, a class of dodecahedra constructed from a hexahedron by adding a diagonal in each face of the hexahedron, and a triangulation of a sphere with 3n (n≥2) vertices.
基金supported by the National Natural Science Foundation of China(No.41601344)the Fundamental Research Funds for the Central Universities(Nos.300102320107 and 201924)+2 种基金the National Key Research and Development Project(No.2020YFC1512000)in part by the General Projects of Key R&D Programs in Shaanxi Province(No.2020GY-060)Xi’an Science&Technology Project(Nos.2020KJRC0126 and 202018)。
文摘As a key technique in hyperspectral image pre-processing,dimensionality reduction has received a lot of attention.However,most of the graph-based dimensionality reduction methods only consider a single structure in the data and ignore the interfusion of multiple structures.In this paper,we propose two methods for combining intra-class competition for locally preserved graphs by constructing a new dictionary containing neighbourhood information.These two methods explore local information into the collaborative graph through competing constraints,thus effectively improving the overcrowded distribution of intra-class coefficients in the collaborative graph and enhancing the discriminative power of the algorithm.By classifying four benchmark hyperspectral data,the proposed methods are proved to be superior to several advanced algorithms,even under small-sample-size conditions.
基金This paper was supported by the National Natural Science Foundation of China (61472345, 61562091), the Natural Science Foundation of Yunnan Province (2014FA023,2013FB010), the Program for Innovative Research Team in Yunnan University (XT412011), the Program for Excellent Young Talents of Yunnan University (XT412003), Yunnan Provincial Foundation for Leaders of Disciplines in Science and Technology (2012HB004), and the Research Foundation of the Educational Department of Yunnan Province (2014C134Y).
文摘There exist two or more competing products in viral marketing, and the companies can exploit the social interactions of users to propagate the awareness of products. In this paper, we focus on selecting seeds for maximizing the competitive influence spread in social networks. First, we establish the possible graphs based on the propagation probability of edges, and then we use the competitive influence spread model (CISM) to model the competitive spread under the possible graph. Further, we consider the objective function of selecting k seeds of one product under the CISM when the seeds of another product have been known, which is monotone and submodular, and thus we use the CELF (cost-effective lazy forward) algorithm to accelerate the greedy algorithm that can approximate the optimal with 1 ? 1/e. Experimental results verify the feasibility and effectiveness of our method.
文摘为整体审视我国体育后备人才研究的发展动态、前沿热点与演进历程,以期为我国体育后备人才研究提供理论依据与参考,使得研究能与实践深度融合,在体育强国的时代背景下实现应用价值最大化。本文采用Cite Space V软件与文献计量方法对1986-2021年CNKI学术期刊数据库收录的1496篇体育后备人才研究文献进行研究,结果表明:我国体育后备人才年发文量呈波浪式增长,分为孕育萌芽阶段、快速发展阶段与稳步增长阶段三个阶段,学术关注度呈现“前低后高”;合作网络之间较少而松散,仅形成了两个较大的核心合作网络群;研究热点主要集中于体育后备人才宏观研究、体育后备人才培养与竞技体育等方面;主题研究演进经历了4个时期:开篇布局时期(1986-2001年)、体教结合时期(2002-2008年)、后奥运会时期(2009-2019年)与体教融合时期(2020至今)。
文摘Let D be a digraph.The competition graph of D is the graph having the same vertex set with D and having an edge joining two different vertices if and only if they have at least one common out-neighbor in D.The phylogeny graph of D is the competition graph of the digraph constructed from D by adding loops at all vertices.The competition/phylogeny number of a graph is the least number of vertices to be added to make the graph a competition/phylogeny graph of an acyclic digraph.In this paper,we show that for any integer k there is a connected graph such that its phylogeny number minus its competition number is greater than k.We get similar results for hypergraphs.
