Atsushi Takizawa

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Given a directed graph <i>D = (V, A)</i> and a set of specified vertices S = {s<sub>1</sub>,&#8230;,s<sub>d</sub>} &#8838; <i>V</i> with |S| = <i>d</i> and a function <i>f</i>: S &#8594; N where N denotes the set of natural numbers, we present a necessary and sufficient condition that there exist &#931;s<sub>i</sub> &#949; arc-disjoint in-trees denoted by(More)
In recent years, catastrophic disasters by massive earthquakes are increasing in the world, and disaster management is required more than ever. In the case of disasters such as tsunami from which the slight delay of evacuation deprives of life. In this article, we formalize the emergency evacuation planning model for the evacuation from tsunami etc. based(More)
Using spatial data mining techniques, we analyze car-related crimes such as auto theft, auto parts theft, and breaking into a car in the area of Nishikyo-ku, Kyoto City. The strategy of natural surveillance proposed by Crime Prevention Through Environmental Design (CPTED) is taken into consideration as visibility attributes. From the viewpoint of risk(More)