Searchlight scheduling problem

Kazuo Sugihara, Ichiro Suzuki, Masafumi Yamashita

Research output: Contribution to journalArticle

25 Citations (Scopus)

Abstract

The problem of searching for a mobile robber in a simple polygon by a number of searchlights is considered. A searchlight is a stationary point which emits a single ray that cannot penetrate the boundary of the polygon. The direction of the ray can be changed continuously, and a point is detected by a searchlight at a given time if and only if it is on the ray. A robber is a point that can move continuously with unbounded speed. First, it is shown that the problem of obtaining a search schedule for an instance having at least one searchlight on the polygon boundary can be reduced to that for instances having no searchlight on the polygon boundary. The reduction is achieved by a recursive search strategy called the one-way sweep strategy. Then various sufficient conditions for the existence of a search schedule are presented by using the concept of a searchlight visibility graph. Finally, a simple necessary and sufficient condition for the existence of a search schedule for instances having exactly two searchlights in the interior is presented.

Original languageEnglish
Pages (from-to)1024-1040
Number of pages17
JournalSIAM Journal on Computing
Volume19
Issue number6
DOIs
Publication statusPublished - Jan 1 1990

Fingerprint

Searchlights
Polygon
Half line
Scheduling Problem
Schedule
Scheduling
Visibility Graph
Simple Polygon
Sufficient Conditions
Stationary point
Search Strategy
Sweep
Interior
If and only if
Necessary Conditions
Visibility

All Science Journal Classification (ASJC) codes

  • Computer Science(all)
  • Mathematics(all)

Cite this

Sugihara, K., Suzuki, I., & Yamashita, M. (1990). Searchlight scheduling problem. SIAM Journal on Computing, 19(6), 1024-1040. https://doi.org/10.1137/0219070

Searchlight scheduling problem. / Sugihara, Kazuo; Suzuki, Ichiro; Yamashita, Masafumi.

In: SIAM Journal on Computing, Vol. 19, No. 6, 01.01.1990, p. 1024-1040.

Research output: Contribution to journalArticle

Sugihara, K, Suzuki, I & Yamashita, M 1990, 'Searchlight scheduling problem', SIAM Journal on Computing, vol. 19, no. 6, pp. 1024-1040. https://doi.org/10.1137/0219070
Sugihara K, Suzuki I, Yamashita M. Searchlight scheduling problem. SIAM Journal on Computing. 1990 Jan 1;19(6):1024-1040. https://doi.org/10.1137/0219070
Sugihara, Kazuo ; Suzuki, Ichiro ; Yamashita, Masafumi. / Searchlight scheduling problem. In: SIAM Journal on Computing. 1990 ; Vol. 19, No. 6. pp. 1024-1040.
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