Documents disponibles écrits par cet auteur

An exact method for minimizing the total treatment time in intensity-modulated radiotherapy / L. R. Mason in Journal of the operational research society (JORS), Vol. 63 N° 10 (Octobre 2012) 

Public ISBD [article]  in Journal of the operational research society (JORS) > Vol. 63 N° 10 (Octobre 2012) . - pp. 1447–1456 Titre : An exact method for minimizing the total treatment time in intensity-modulated radiotherapy Type de document : texte imprimé Auteurs : L. R. Mason, Auteur ; V. H. Mak-Hau, Auteur ; A. T. Ernst, Auteur Année de publication : 2012 Article en page(s) : pp. 1447–1456 Note générale : operational research Langues : Anglais (eng) Mots-clés : integer  programming;  combinatorial  optimization;  constraint  programming Index. décimale : 001.424 Résumé : In this paper, we solve a combinatorial optimization problem that arises from the treatment planning of a type of radiotherapy where intensity is modulated by multileaf collimators (MLC) in a step-and-shoot manner. In Ernst et al [INFORMS Journal on Computing 21 (4) (2009): 562–574], we proposed an exact method for minimizing the number of MLC apertures needed for a treatment. Our method outperformed the fastest algorithms available at the time. We refer to our method as the CPI method. We now attempt to minimize the total treatment time by modifying our CPI method. This modification involves non-trivial work, as some of the search space elimination schemes used in the CPI method cannot be applied in here. In our numerical experiments, we again compare our new method with the fastest algorithms currently available. There has been significant recent research in this area; hence we compare our method with those published in Wake et al [Computers and Operations Research 36 (2009): 795–810], Taşkin et al [Operations Research 58 (3) (2010): 674–690] and Cambazard et al [CPAIRO (2010): 1–16]. The numerical comparisons indicate that our method generally outperformed the first two, while being competitive with the third. DEWEY : 001.424 ISSN : 0160-5682 En ligne : http://www.palgrave-journals.com/jors/journal/v63/n10/abs/jors2011158a.html [article] An exact method for minimizing the total treatment time in intensity-modulated radiotherapy [texte imprimé] / L. R. Mason, Auteur ; V. H. Mak-Hau, Auteur ; A. T. Ernst, Auteur . - 2012 . - pp. 1447–1456. operational research Langues : Anglais (eng) in Journal of the operational research society (JORS) > Vol. 63 N° 10 (Octobre 2012) . - pp. 1447–1456 Mots-clés : integer  programming;  combinatorial  optimization;  constraint  programming Index. décimale : 001.424 Résumé : In this paper, we solve a combinatorial optimization problem that arises from the treatment planning of a type of radiotherapy where intensity is modulated by multileaf collimators (MLC) in a step-and-shoot manner. In Ernst et al [INFORMS Journal on Computing 21 (4) (2009): 562–574], we proposed an exact method for minimizing the number of MLC apertures needed for a treatment. Our method outperformed the fastest algorithms available at the time. We refer to our method as the CPI method. We now attempt to minimize the total treatment time by modifying our CPI method. This modification involves non-trivial work, as some of the search space elimination schemes used in the CPI method cannot be applied in here. In our numerical experiments, we again compare our new method with the fastest algorithms currently available. There has been significant recent research in this area; hence we compare our method with those published in Wake et al [Computers and Operations Research 36 (2009): 795–810], Taşkin et al [Operations Research 58 (3) (2010): 674–690] and Cambazard et al [CPAIRO (2010): 1–16]. The numerical comparisons indicate that our method generally outperformed the first two, while being competitive with the third. DEWEY : 001.424 ISSN : 0160-5682 En ligne : http://www.palgrave-journals.com/jors/journal/v63/n10/abs/jors2011158a.html

Dynamic scheduling of recreational rental vehicles with revenue management extensions / A. T. Ernst in Journal of the operational research society (JORS), Vol. 61 N° 7 (Juillet 2010) 

Public ISBD [article]  in Journal of the operational research society (JORS) > Vol. 61 N° 7 (Juillet 2010) . - pp. 1133–1143 Titre : Dynamic scheduling of recreational rental vehicles with revenue management extensions Type de document : texte imprimé Auteurs : A. T. Ernst, Auteur ; M. Horn, Auteur ; P. Kilby, Auteur Année de publication : 2011 Article en page(s) : pp. 1133–1143 Note générale : Recherche opérationnelle Langues : Anglais (eng) Mots-clés : Scheduling  Networks  and  graphs  Revenue  management  Vehicle  routing Index. décimale : 001.424 Résumé : The rental fleet scheduling problem (RFSP) arises in vehicle-rental operations that offer a wide variety of vehicle types to customers, and allow a rented vehicle to ‘migrate’ to a setdown depot other than the pickup depot. When there is a shortage of vehicles of a particular type at a depot, vehicles may be relocated to that depot, or vehicles of similar types may be substituted. The RFSP involves assigning vehicles to rentals so as to minimise the costs of these operations, and arises in both static and online contexts. The authors have adapted a well-known assignment algorithm for application in the online context. In addition, a network-flow algorithm with more comprehensive coverage of problem conditions is used to investigate the determination of rental pricing using revenue management principles. The paper concludes with an outline of the algorithms’ use in supporting the operations of a large recreational vehicle rental company. DEWEY : 001.424 ISSN : 0361-5682 En ligne : http://www.palgrave-journals.com/jors/journal/v61/n7/abs/jors200978a.html [article] Dynamic scheduling of recreational rental vehicles with revenue management extensions [texte imprimé] / A. T. Ernst, Auteur ; M. Horn, Auteur ; P. Kilby, Auteur . - 2011 . - pp. 1133–1143. Recherche opérationnelle Langues : Anglais (eng) in Journal of the operational research society (JORS) > Vol. 61 N° 7 (Juillet 2010) . - pp. 1133–1143 Mots-clés : Scheduling  Networks  and  graphs  Revenue  management  Vehicle  routing Index. décimale : 001.424 Résumé : The rental fleet scheduling problem (RFSP) arises in vehicle-rental operations that offer a wide variety of vehicle types to customers, and allow a rented vehicle to ‘migrate’ to a setdown depot other than the pickup depot. When there is a shortage of vehicles of a particular type at a depot, vehicles may be relocated to that depot, or vehicles of similar types may be substituted. The RFSP involves assigning vehicles to rentals so as to minimise the costs of these operations, and arises in both static and online contexts. The authors have adapted a well-known assignment algorithm for application in the online context. In addition, a network-flow algorithm with more comprehensive coverage of problem conditions is used to investigate the determination of rental pricing using revenue management principles. The paper concludes with an outline of the algorithms’ use in supporting the operations of a large recreational vehicle rental company. DEWEY : 001.424 ISSN : 0361-5682 En ligne : http://www.palgrave-journals.com/jors/journal/v61/n7/abs/jors200978a.html