15 citations · 19 across the 15 of their papers we have counts for
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Perfect Roman domination in middle graphs
Kijung Kim
The middle graph of a graph is the graph obtained by subdividing each edge of exactly once and joining all these newly introduced vertices of adjacent edges of .…
Restrained Italian domination in trees
Kijung Kim
Let be a graph. A subset of is a \textit{restrained dominating set} if every vertex in is adjacent to a vertex in and to a vertex in $V \setmi…
Two-valenced association schemes and the Desargues theorem
Mitsugu Hirasaka, Kijung Kim, Ilia Ponomarenko
The main goal of the paper is to establish a sufficient condition for a two-valenced association scheme to be schurian and separable. To this end, an analog of the Desargues theore…
Schurity and separability of quasiregular coherent configurations
Mitsugu Hirasaka, Kijung Kim, Ilia Ponomarenko
A permutation group is said to be quasiregular if every its transitive constituent is regular, and a quasiregular coherent configuration can be thought as a combinatorial analog of…
Association schemes all of whose symmetric fusion schemes are integral
Mitsugu Hirasaka, Kijung Kim, Semin Oh
In this paper we aim to characterize association schemes all of whose symmetric fusion schemes have only integral eigenvalues, and classify those obtained from a regular action of…
Association schemes in which the thin residue is an elementary abelian -group of rank
Mitsugu Hirasaka, Kijung Kim
In this article, we investigate the existence and schurity problem of association schemes whose thin residues are isomorphic to an elementary abelian -group of rank .