Hiroshima Institute of Technology

The uniqueness of covers of widely generalized line graphs

As a natural generalization of line graphs, Hoffman line graphs were defined by Woo and Neumaier. Especially, Hoffman line graphs are closely related to the smallest eigenvalues of graphs, and the uniqueness of strict covers of a Hoffman line graph plays a key role in such a stud...

Media Characteristics Analysis of Regional Resource Promotion for Young Generations Using the Metaverse

ABSTRACT This study investigates the media characteristics and effectiveness of virtual reality (VR)‐based regional promotion using a metaverse environment. A virtual world utilizing VR technology was developed to promote tangible cultural properties in the Hatsukaichi area of Hi...

Helicity conservation of the Riemann–Silberstein vector

Abstract In this paper, we consider Riemann–Silberstein (RS) helicity (RSH) given by the sum of the electric and magnetic helicities. We show that this quantity is chiral under parity transformation and invariant under duality. In the case of null fields in free space, we prove t...