Spectra and energy of bipartite signed digraphs
نویسندگان
چکیده
منابع مشابه
On the Energy of Bicyclic Signed Digraphs
Among unicyclic digraphs and signed digraphs with fixed number of vertices, the digraphs and signed digraphs with minimal and maximal energy are already determined. In this paper we address the problem of finding bicyclic signed digraphs with extremal energy. We obtain minimal and maximal energy among all those n -vertex bicyclic signed digraphs which contain vertex-disjoint signed directed cyc...
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We associate a signed digraph with a list of matrices whose dimensions permit them to be multiplied, and whose product is square. Cycles in this graph have a parity, that is, they are either even (termed e-cycles) or odd (termed o-cycles). The absence of e-cycles in the graph is shown to imply that the matrix product is a P0-matrix, i.e., all of its principal minors are nonnegative. Conversely,...
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A signed bipartite graph G(U, V) is a bipartite graph in which each edge is assigned a positive or a negative sign. The signed degree of a vertex x in G(U, V) is the number of positive edges incident with x less the number of negative edges incident with x. The set S of distinct signed degrees of the vertices of G(U, V) is called its signed degree set. In this paper, we prove that every set of ...
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ژورنال
عنوان ژورنال: Linear and Multilinear Algebra
سال: 2015
ISSN: 0308-1087,1563-5139
DOI: 10.1080/03081087.2015.1123670