积运算符号图的谱

Spectra of product operation signed graphs

对图中的每条边标记正边或负边,这样的图称为符号图。给出符号图的积运算(对称积、直积、半强积、强积)的定义,得到这些积运算符号图邻接矩阵的张量形式,并得到积运算(直积、半强积、强积)符号图的邻接谱。

A graph whose edges are labeled either as positive or negative is called a signed graph.The product operations,i.e.symmetric product,direct product,semi-strong product and strong product,of signed graphs are given,respectively.The adjacency matrices of these product operation signed graphs in tensor form are obtained,and some relations on the eigenvalues of signed graphs on product operations(direct product,semi-strong product,strong product)are also formulated.