@misc{ErdmannLangSeebass, author = {Erdmann, Bodo and Lang, Jens and Seebass, Martin}, title = {Adaptive Solutions of Nonlinear Parabolic Equations with Application to Hyperthermia Treatments}, url = {http://nbn-resolving.de/urn:nbn:de:0297-zib-3130}, number = {SC-97-44}, abstract = {We present a self-adaptive finite element method to solve nonlinear evolution problems in 3D. An implicit time integrator of Rosenbrock type is coupled with a multilevel approach in space. The proposed method is applied to hyperthermia treatments to demonstrate its potential for the solving of complicated problems.}, language = {en} } @misc{LangErdmannSeebass, author = {Lang, Jens and Erdmann, Bodo and Seebass, Martin}, title = {Impact of Nonlinear Heat Transfer on Temperature Control in Regional Hyperthermia}, url = {http://nbn-resolving.de/urn:nbn:de:0297-zib-3426}, number = {SC-97-73}, abstract = {We describe an optimization process specially designed for regional hyperthermia of deep seated tumors in order to achieve desired steady--state temperature distributions. A nonlinear three--dimensional heat transfer model based on temperature--dependent blood perfusion is applied to predict the temperature. Using linearly implicit methods in time and adaptive multilevel finite elements in space, we are able to integrate efficiently the instationary nonlinear heat equation with high accuracy. Optimal heating is obtained by minimizing an integral object function which measures the distance between desired and model predicted temperatures. A sequence of minima is calculated from successively improved constant--rate perfusion models employing a damped Newton method in an inner iteration. We compare temperature distributions for two individual patients calculated on coarse and fine spatial grids and present numerical results of optimizations for a Sigma 60 Applicator of the BSD 2000 Hyperthermia System.}, language = {en} } @misc{ErdmannLangSeebass, author = {Erdmann, Bodo and Lang, Jens and Seebass, Martin}, title = {Optimization of Temperature Distributions for Regional Hyperthermia Based on a Nonlinear Heat Transfer Model}, url = {http://nbn-resolving.de/urn:nbn:de:0297-zib-3283}, number = {SC-97-59}, abstract = {We describe an optimization process specially designed for regional hyperthermia of deap seated tumors in order to achieve desired steady--state temperature distributions. A nonlinear three--dimensional heat--transfer model based on temperature--dependent blood perfusion is applied to predict the temperature. Optimal heating is obtained by minimizing an integral object function which measures the distance between desired and model predicted temperatures. Sequential minima are calculated from successively improved constant--rate perfusion models employing a damped Newton method in an inner iteration. Numerical results for a Sigma 60 applicator are presented. This work has been supported by Deutsche Forschungsgemeinschaft (DFG) within the Sonderforschungsbereich 273 \glqq Hyperthermie: Methodik und Klinik \grqq .}, language = {en} } @inproceedings{ErdmannLangSeebass1997, author = {Erdmann, Bodo and Lang, Jens and Seebass, Martin}, title = {Adaptive Solutions of Nonlinear Parabolic Equations with Application to Hyperthermia Treatments}, series = {CHT'97}, booktitle = {CHT'97}, editor = {de Vahl Davis, G. and Leonardi, E.}, address = {Cesme, Turkey}, pages = {103 -- 110}, year = {1997}, language = {en} } @inproceedings{ErdmannLangSeebass1998, author = {Erdmann, Bodo and Lang, Jens and Seebass, Martin}, title = {Optimization of Temperature Distributions for Regional Hyperthermia based on a Nonlinear Heat Transfer Model}, series = {Biotransport}, volume = {858}, booktitle = {Biotransport}, editor = {Diller, K.}, pages = {36 -- 46}, year = {1998}, language = {en} } @article{ErdmannLangSeebass1999, author = {Erdmann, Bodo and Lang, Jens and Seebass, Martin}, title = {The Impact of a Nonlinear Heat Transfer Model for Temperature Control in Regional Hyperthermia}, series = {IEEE Transactions on Biomedical Engineering}, volume = {49}, journal = {IEEE Transactions on Biomedical Engineering}, number = {9}, pages = {1129 -- 1138}, year = {1999}, language = {en} } @article{LangErdmannSeebass1999, author = {Lang, Jens and Erdmann, Bodo and Seebaß, Martin}, title = {Impact of Nonlinear Heat Tansfer on Temperature Control in Regional Hypertermia}, series = {IEEE Trans. Biomed. Engrg.}, volume = {46}, journal = {IEEE Trans. Biomed. Engrg.}, doi = {10.1109/10.784145}, pages = {1129 -- 1138}, year = {1999}, language = {en} }