Optimization of the deposited power distribution inside a layered lossy medium irradiated by a coupled system of concentrically placed waveguide applicators

Nikita, KS; Maratos, NG; Uzunoglu, NK

dc.contributor.author	Nikita, KS	en
dc.contributor.author	Maratos, NG	en
dc.contributor.author	Uzunoglu, NK	en
dc.date.accessioned	2014-03-01T01:13:58Z
dc.date.available	2014-03-01T01:13:58Z
dc.date.issued	1998	en
dc.identifier.issn	0018-9294	en
dc.identifier.uri	https://dspace.lib.ntua.gr/xmlui/handle/123456789/12822
dc.subject	Hyperthermia	en
dc.subject	Optimization	en
dc.subject	Phased array	en
dc.subject.classification	Engineering, Biomedical	en
dc.subject.other	Bioelectric phenomena	en
dc.subject.other	Electromagnetic wave absorption	en
dc.subject.other	Optimization	en
dc.subject.other	Tissue	en
dc.subject.other	Waveguides	en
dc.subject.other	Specific absorption rate (SAR)	en
dc.subject.other	Waveguide applicators	en
dc.subject.other	Hyperthermia therapy	en
dc.subject.other	article	en
dc.subject.other	electromagnetic field	en
dc.subject.other	heat exchange	en
dc.subject.other	hyperthermia	en
dc.subject.other	mathematical analysis	en
dc.subject.other	Algorithms	en
dc.subject.other	Electricity	en
dc.subject.other	Electromagnetic Fields	en
dc.subject.other	Equipment Design	en
dc.subject.other	Humans	en
dc.subject.other	Hyperthermia, Induced	en
dc.subject.other	Models, Biological	en
dc.title	Optimization of the deposited power distribution inside a layered lossy medium irradiated by a coupled system of concentrically placed waveguide applicators	en
heal.type	journalArticle	en
heal.identifier.primary	10.1109/10.686799	en
heal.identifier.secondary	http://dx.doi.org/10.1109/10.686799	en
heal.language	English	en
heal.publicationDate	1998	en
heal.abstract	A method is proposed for controlling the deposited power distribution in a layered cylindrical lossy model, irradiated by a phased-array hyperthermia system consisting of four waveguide applicators. A rigorous electromagnetic model of the heated tissue, which takes into account coupling phenomena between system elements, is used for predicting the electric field at any point inside tissue. The relative amplitudes and relative phases of the array elements are optimized in order to attain desired specific absorption rate (SAR) distributions inside and outside malignant tissues. A constrained nonlinear optimization problem is solved by using the penalty function method and the resulting unconstrained minimization of the penalty function is carried out by the downhill simplex method. Two practical phased-array hyperthermia systems have been studied and numerical results are presented.A method is proposed for controlling the deposited power distribution in a layered cylindrical lossy model, irradiated by a phased-array hyperthermia system consisting of four waveguide applicators. A rigorous electromagnetic model of the heated tissue, which takes into account coupling phenomena between system elements, is used for predicting the electric field at any point inside tissue. The relative amplitudes and relative phases of the array elements are optimized in order to attain desired specific absorption rate (SAR) distributions inside and outside malignant tissues. A constrained nonlinear optimization problem is solved by using the penalty function method and the resulting unconstrained minimization of the penalty function is carried out by the downhill simplex method. Two practical phased-array hyperthermia systems have been studied and numerical results are presented.	en
heal.publisher	IEEE, Piscataway, NJ, United States	en
heal.journalName	IEEE Transactions on Biomedical Engineering	en
dc.identifier.doi	10.1109/10.686799	en
dc.identifier.isi	ISI:000074261500012	en
dc.identifier.volume	45	en
dc.identifier.issue	7	en
dc.identifier.spage	909	en
dc.identifier.epage	920	en