{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2024,2,6]],"date-time":"2024-02-06T23:44:02Z","timestamp":1707263042991},"reference-count":7,"publisher":"World Scientific Pub Co Pte Lt","issue":"03","content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Int. J. Comput. Geom. Appl."],"published-print":{"date-parts":[[2014,9]]},"abstract":"<jats:p> Let P and F be sets of n \u2265 2 and m \u2265 2 points in a plane, respectively. We study the problem of finding the minimum angle \u03b1 \u03f5 [2\u03a0\/m, 2\u03a0] such that one can install at each point of F a stationary rotating floodlight with illumination angle \u03b1, initially oriented in a suitable direction, in such a way that, at all times, every target point of P is illuminated by at least one floodlight. All floodlights rotate clockwise at unit speed. We provide bounds for the case in which the elements of P \u22c3 F are on a given line, and present exact results for the case in the plane in which we have two floodlights and many target points. We further consider the non-rotating version of the problem and look for the minimum angle \u03b1 such that one can install a non-rotating floodlight with illumination angle \u03b1 at each point of F, in such a way that every target point of P is illuminated by at least one floodlight. We show that this problem is NP-hard and hard to approximate. <\/jats:p>","DOI":"10.1142\/s0218195914600024","type":"journal-article","created":{"date-parts":[[2015,3,17]],"date-time":"2015-03-17T07:21:38Z","timestamp":1426576898000},"page":"183-196","source":"Crossref","is-referenced-by-count":2,"title":["CONTINUOUS SURVEILLANCE OF POINTS BY ROTATING FLOODLIGHTS"],"prefix":"10.1142","volume":"24","author":[{"given":"S.","family":"BEREG","sequence":"first","affiliation":[{"name":"Department of Computer Science, University of Texas, Dallas, Texas, USA"}]},{"given":"J. M.","family":"D\u00cdAZ-B\u00c1\u00d1EZ","sequence":"additional","affiliation":[{"name":"Departamento Matem\u00e1tica Aplicada II, Universidad de Sevilla, Sevilla, Spain"}]},{"given":"M.","family":"FORT","sequence":"additional","affiliation":[{"name":"Departament d'Inform\u00e1tica i Matem\u00e1tica Aplicada, Universitat de Girona, Girona, Spain"}]},{"given":"M. A.","family":"LOPEZ","sequence":"additional","affiliation":[{"name":"Department of Computer Science, University of Denver, Denver, USA"}]},{"given":"P.","family":"P\u00c9REZ-LANTERO","sequence":"additional","affiliation":[{"name":"Escuela de Ingenier\u00eda Civil en Inform\u00e1tica, Universidad de Valpara\u00edso, Valparaiso, Chile"}]},{"given":"J.","family":"URRUTIA","sequence":"additional","affiliation":[{"name":"Instituto de Matem\u00e1ticas, UNAM, Mexico D.F., Mexico"}]}],"member":"219","published-online":{"date-parts":[[2015,3,16]]},"reference":[{"key":"p_1","doi-asserted-by":"publisher","DOI":"10.1142\/S0218195997000090"},{"key":"p_2","doi-asserted-by":"publisher","DOI":"10.1016\/j.comgeo.2007.01.004"},{"key":"p_4","doi-asserted-by":"publisher","DOI":"10.1007\/s10472-010-9193-y"},{"key":"p_7","doi-asserted-by":"publisher","DOI":"10.1016\/0167-6377(82)90039-6"},{"key":"p_9","doi-asserted-by":"publisher","DOI":"10.1007\/s00454-004-1091-9"},{"key":"p_10","doi-asserted-by":"publisher","DOI":"10.1016\/S0925-7721(97)00027-8"},{"key":"p_11","doi-asserted-by":"publisher","DOI":"10.1137\/0219070"}],"container-title":["International Journal of Computational Geometry &amp; Applications"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/www.worldscientific.com\/doi\/pdf\/10.1142\/S0218195914600024","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2019,8,6]],"date-time":"2019-08-06T20:47:05Z","timestamp":1565124425000},"score":1,"resource":{"primary":{"URL":"https:\/\/www.worldscientific.com\/doi\/abs\/10.1142\/S0218195914600024"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2014,9]]},"references-count":7,"journal-issue":{"issue":"03","published-online":{"date-parts":[[2015,3,16]]},"published-print":{"date-parts":[[2014,9]]}},"alternative-id":["10.1142\/S0218195914600024"],"URL":"https:\/\/doi.org\/10.1142\/s0218195914600024","relation":{},"ISSN":["0218-1959","1793-6357"],"issn-type":[{"value":"0218-1959","type":"print"},{"value":"1793-6357","type":"electronic"}],"subject":[],"published":{"date-parts":[[2014,9]]}}}