Dr. techn. Karl Hollaus
AddressInstitute for Analysis and Scientific Computing phone: +43 1 58801 10116 email: karl.hollaus@tuwien.ac.at |
Workshop
Projects
Research Interests
Computational Electromagnetics, Finite Element Method, Multiscale Method and Homogenization, Domain Decomposition, Software Development (Netgen/NGSolve)
Diploma Thesis
Identifikation optimaler Geometrieparameter einer SMES - Spulenanordnung mit deterministischen und stochastischen Optimierungsverfahren, TU Graz and Dipartimento di Ingegneria Elettrica, Università degli Studi di Genova, 1997.
PhD Thesis
Numerical Simulation of Eddy Currents and the Associated Losses in Laminated Ferromagnetic Materials by the Method of Finite Elements, TU Graz, 2001. pdf
Teaching
"Partielle Differentialgleichungen und Methode der finiten Elemente"
Talks
- Homogenization of Laminated Cores and the Role of Surface Charges, ICEAA2017, Verona, Italy, Sept. 11 - 15, 2017.
- Multiscale Finite Element Method and Geometric Perturbation of Laminated Cores, ICEAA2017, Verona, Italy, Sept. 11 - 15, 2017.
- Multiscale and Harmonic Balance FEM for the Eddy Current Problem in Laminated Iron Cores, CEFC 2016, Miami, USA, Nov. 13 - 16, 2016. pdf
- Various Two Dimensional Multiscale Finite Element Formulations for the Eddy Current Problem in Iron Laminates, EMF 2016, Lyon, France, April 12 - 14, 2016. pdf (highlighted talk)
- Multi-Scale Finite Element Method to Simulate Eddy Currents in Laminated Iron, SCEE 2014, Wuppertal, Germany, July 22 - 25, 2014. pdf
- Two-Scale Homogenization of the Nonlinear Eddy Current Problem with FEM, Compumag 2013, Budapest, June 30 - July 4, 2013. pdf
- FEM: Domain Decomposition and Homogenization for Maxwell's Equations of Large Scale Problems, TCSE Vienna Workshop 2012, Vienna, February 13, 2012. pdf
- Homogenization of the Eddy Current Problem in 2D, 14th International IGTE Symposium 2010, Graz, Austria, Sept. 19 - 22, 2010. pdf
- Novel Variation Formulation for Domain Decomposition to solve Maxwell's Equations, DSPDES 2010, Barcelona, Spain, June 3, 2010. pdf
Recent Work
- Air Gap and Edge Effect in the 2D/1D-Method with the Magnetic Vector Potential A using MSFEM, Digest for CEFC 2018, Hangzhou, China, Oct. 28 - 31, 2018 (submitted, May, 2018). preprint
- Simple and Cheap Structural MOR Method for the 2D/1D-MSFEM, Digest for CEFC 2018, Hangzhou, China, Oct. 28 - 31, 2018 (submitted, May, 2018). preprint
- A 2D/1D Multiscale FEM Model for the Nonlinear Eddy Current Problem in Thin Sheets, Digest for CEFC 2018, Hangzhou, China, Oct. 28 - 31, 2018 (submitted, May, 2018). preprint
- MSFEM and MOR to simulate one laminate for electrical machines, Abstract for EMF 2018, Darmstadt, Germany, April 10 - 12, 2018 (submitted, Dec., 2017). preprint
- MOR for the MSFEM of the Eddy Current Problem in Linear Laminated Media, Abstract for MATHMOD 2018, Vienna, Austria, Feb. 21 - 23, 2018 (submitted, Nov., 2017). preprint
- MSFEM for the Linear 2D1D-Problem of Eddy Currents in Thin Iron Sheets, Abstract for MATHMOD 2018, Vienna, Austria, Feb. 21 - 23, 2018 (submitted, Nov., 2017). preprint
- MSFEM with Network Coupling for the Eddy Current Problem of a Toroidal Transformer, Abstract for ISTET 2017, Ilmenau, Germany, July 16 - 19, 2017 (submitted, April, 2017). preprint
- A Mixed Multiscale Finite Element Method with A and J for Eddy Currents in Iron Laminates, Digest for Compumag 2017, Daejeon, Korea, June 18 - 22, 2017 (submitted, Jan., 2017). preprint
- Transient Finite Element Simulation of Non-Linear Eddy Current Problems with Biot-Savart-Field of Voltage-Driven Coils, Digest for Compumag 2017, Daejeon, Korea, June 18 - 22, 2017 (submitted, Jan., 2017). preprint
- Adaptive Mesh Refinement for Multi-Scale FEM for the Eddy Current Problem in Laminated Materials, Digest for Compumag 2017, Daejeon, Korea, June 18 - 22, 2017 (submitted, Jan., 2017). preprint
- Multiscale and Harmonic Balance FEM for the Eddy Current Problem in Laminated Iron Cores, Short paper for CEFC 2016, Miami, USA, Nov. 13 - 16, 2016 (submitted, April, 2016). preprint
- An Efficient Reformulation of a Multiscale Method for the Eddy Current Problem, Abstract for IGTE 2016, Graz, Austria, Sept. 18 - 21, 2016. preprint
- A Mixed Multiscale Finite Element Method for 3D Eddy Currents in Iron Laminates, Abstract for IGTE 2016, Graz, Austria, Sept. 18 - 21, 2016. preprint
- Various two dimensional multi-scale finite element formulations for the eddy current problem in iron laminates, Abstract for EMF 2016, Lyon, France, from 12 to 14 April 2016. preprint
- Multi-Scale FEM Modeling of Eddy Currents with a Current Vector Potential T in Laminated Media, Short paper for Compumag 2015, Montreal, Canada, 28 June - 2 July, 2015 (accepted, March, 2015). preprint
- MSFEM to Simulate Eddy Currents in Laminated Iron, Abstract for Scientific Computing in Electrical Engineering SCEE 2014, Wuppertal, Germany, July 22 - 25, 2014. (submitted, June, 2014). pdf
- Multi-scale FEM for the eddy current problem in laminated media, Short paper for CEFC 2014, Annecy, France, May 25 - 28, 2014 (submitted, Dec., 2013). preprint
Publications
- K. Hollaus, J. Schöberl, "Some Two-Dimensional Multiscale Finite Element Formulations for the Eddy Current Problem in Iron Laminates", IEEE Transactions on Magnetics, vol. 54, no. 4, 2018. online
- K. Hollaus, M. Schöbinger, "Multiscale finite element method for perturbation of laminated structures", In ICEAA 2017, pages 1262-1263. online
- M. Schöbinger, K. Hollaus, I. Tsukerman, "Homogenization of laminated magnetic cores and the role of surface charges", In ICEAA 2017, pages 971-972. online
- Markus Schöbinger, J. Schöberl, K. Hollaus, "Adaptive Mesh Refinement for Multi-Scale FEM for the Eddy Current Problem in Laminated Materials", IEEE Transactions on Magnetics, vol. 54, no. 3, 2018. online
- Markus Schöbinger, J. Schöberl, K. Hollaus, "An Efficient Reformulation of a Multiscale Method for the Eddy Current Problem," COMPEL, vol. 36, pp. 1421-1429, 2017.
- K. Hollaus, "Multiscale and Harmonic Balance FEM for the Eddy Current Problem in Laminated Iron Cores". In Proc. 17th IEEE CEFC 2016, 13-16 Nov. 2016, Miami, USA.
- H. Davtjan, M. Kaltenbacher, J. Schöberl, M. Schöbinger, K. Hollaus, "Multiscale finite element methods for eddy current problems in laminated iron MSFEM4ECP", Technical article, Newsletter, International Compumag Society, Volume 23 No. 2. July, 2016.
- K. Hollaus, J. Schöberl, "Multi-scale FEM and magnetic vector potential A for 3D eddy currents in laminated media," COMPEL, vol. 34, no. 5, pp. 1598-1608, 2015. online
- K. Hollaus, J. Schöberl, "A Higher Order Multi-Scale FEM with A for 2D Eddy Current Problems in Laminated Iron", IEEE Transactions on Magnetics, vol. 51, no. 3, 7402804, March, 2015. Draft pdf
- K. Hollaus, A. Hannukainen, J. Schöberl, "Two-Scale Homogenization of the Nonlinear Eddy Current Problem with FEM," IEEE Transactions on Magnetics, vol. 50, no. 2, pp. 413-416, Feb., 2014. online
- K. Hollaus, M. Huber, J. Schöberl, P. Hamberger, "A Linear FEM Benchmark for the Homogenization of the Eddy Currents in Laminated Media in 3D," International Federation of Automatic Control IFAC, vol. 7, no. 1, pp. 1190-1194, 2012. preprint
- K. Hollaus, J. Schöberl, "Two-scale FEM for the linear Eddy Current Problem in 3D," Proceedings of the 18th Compumag Conference on the Computation of Electromagnetic Fields, 12-15 July 2011, Sydney, Australia. preprint
- K. Hollaus, J. Schöberl, "Homogenization of the Eddy Current Problem in 2D," Proceedings of the 14th International IGTE Symposium on Numerical Field Calculation in Electrical Engineering, pp. 154-159, Graz, Austria, September 19-22, 2010. preprint
- K. Hollaus, D. Feldengut, J. Schöberl, M. Wabro, D. Omeragic, "Nitsche-type Mortaring for Maxwell's Equations," Progress In Electromagnetics Research Symposium Proceedings, 397 - 402, July 5-8, Cambridge, USA 2010. preprint
- K. Hollaus, O. Bíró, P. Caldera, G. Matzenauer, G. Paoli, K. Preis, C. Stockreiter, "Extraction of Circuit Parameters from PCB by FDTD and SIBC," COMPEL, vol. 28, no. 4, pp. 1091-1101, 2009. online
- Björk et al., "System-Level Design," in G.Q. Zhang, A.J. van Roosmalen "More than Moore - Creating High Value Micro/Nanoelectronics Systems," Springer, pp. 305-330, 2009. online
- K. Hollaus, O. Bíró, P. Caldera, G. Matzenauer, G. Paoli, and G. Plieschenegger, "Simulation of Crosstalk on Printed Circuit Boards by FDTD, FEM, and a Circuit Model," IEEE Transactions on Magnetics, vol. 44, pp. 1486-1489, April 2008. online
- K. Hollaus, O. Bíró, K. Preis and C. Stockreiter, "Edge finite elements coupled with a circuit for wave problems," Internat. Conf. on Electromagnetics in Advanced Applications, ICEAA 2007, IEEE Xplore, pp. 956-959, Torino, Italy, 17th –21st Sept. 2007. online
- B. Weiß, O. Bíró, P. Caldera, K. Hollaus, G. Paoli, K. Preis, "A Multigrid Algorithm for the Transfinite-Element Time-Domain Method using the A, V -Formulation", IEEE Transactions on Magnetics, vol. 43, pp. 1353-1356, April 2007. online
- C. Stockreiter, G. Matzenauer, O. Biro, P. Caldera, G. Paoli, K. Hollaus, K. Preis, B. Weiss, "Transfinite Element Method Using the A, v-Potential Formulation With Edge Elements in the Frequency Domain," IEEE Transactions on Magnetics, vol. 43, pp. 1349-1352, April 2007. online
- W. Renhart, K. Hollaus, C. Magele and G. Matzenauer, "Radiation of USB-WLAN Antenna Influenced by Human Tissue and by Notebook Enclosure," IEEE Transactions on Magnetics, vol. 43, pp. 1345-1348, April 2007. online
- B. Weiß, O. Bíró, P. Caldera, K. Hollaus, G. Paoli, K. Preis, C. Stockreiter, "On the convergence of the transfinite-element method," COMPEL, vol. 26, no. 3, pp. 600-611, 2007. online
- G. Matzenauer, O. Bíró, K. Hollaus, K. Preis, W. Renhart, "Perfectly Matched Layers for T, Phi Formulation," COMPEL, vol. 26, no. 3, pp. 612-625, 2007. online
- H. Scharfetter, K. Hollaus, J. Rosell-Ferrer, R. Merwa, "Single-step 3-D image reconstruction in magnetic induction tomography: Theoretical limits of spatial resolution and contrast to noise ratio," Annals of Biomedical Engineering, pp. 1-13, 2006. online
- K. Hollaus, O. Bíró, P. Caldera, G. Matzenauer, G. Paoli, K. Preis, W. Renhart, C. Stockreiter and B. Weiß, "Simulation of Microstrips on Printed Circuit Boards," Tagungsband des 51. Internationalen Wissenschaftliches Kolloquium der TU Ilmenau, ISBN 3-938843-16-0, 5 pages, Ilmenau, Germany, 11-15, September 2006. preprint
- K. Hollaus, O. Bíró, K. Preis, C. Stockreiter and B. Weiß, "S-Parameter Extraction from Structures on Printed Circuit Boards by FDTD and Surface Impedance Boundary Condition," Proceedings of The Twelfth IEEE Conference on Electromagnetic Field Computation, ISBN 1-4244-0319-7, p. 378, Miami, USA, April 30th-May 3rd, 2006. online
- K. Hollaus, O. Bíró, G. Matzenauer, K. Preis, C. Stockreiter, B. Weiß, P. Caldera and G. Paoli, "Comparison of FETD and FDTD to Simulate Micro-strip Structures on PCBs," Proceedings of The Sixth International Conference on Computation in Electromagnetics CEM 2006, ISBN 3-8007-2957-1, p. 209-210, Aachen, Germany, April 4-6, 2006. preprint
- B. Weiß, O. Bíró, K. Hollaus, K. Preis, P. Caldera, G. Paoli, "A Multigrid Solver for Time Harmonic Three-Dimensional Electromagnetic Wave Problems," IEEE Transactions on Magnetics, vol. 42, pp. 639-642, April 2006. online
- K. Hollaus, O. Bíró, P. Caldera, G. Matzenauer, G. Paoli, K. Preis, C. Stockreiter, and B. Weiss, "Electromagnetic Field Computation of Simple Structures on Printed Circuit Boards by the Finite-Element Method," IEEE Transactions on Magnetics, vol. 42, pp. 815-818, April 2006. online
- B. Wagner, K. Hollaus, Ch. Magele, "Reconstruction of the anisotropic complex conductivity distribution of a human thigh in three dimensions," IEEE Transactions on Magnetics, vol. 42, pp. 1171-1174, April 2006. online
- P. Brunner, R. Merwa, A. Missner, J. Rosell, K. Hollaus, H. Scharfetter, "Reconstruction of the shape of conductivity spectra using differential multi-frequency magnetic induction tomography", Physiol. Meas., vol. 27, no. 5, pp. S237-S248, May 2006. online
- R. Merwa, P. Brunner, A. Missner, K. Hollaus, H. Scharfetter, "Solution of the inverse problem of magnetic induction tomography (MIT) with multiple objects: analysis of detectability and statistical properties with respect to the reconstructed conducting region", Physiol. Meas., vol. 27, no. 5, pp. S249-S259, May 2006. online
- K. Hollaus, B. Wagner, O. Bíró, "Simulation of the quasi-static electric field by an electric current vector potential approximated by edge elements", COMPEL, vol. 24, no. 2, pp. 581-590, 2005. online
- B. Wagner, K. Hollaus, Ch. Magele, "Reconstruction of the anisotropic complex conductivity distribution in 3D", COMPEL, vol. 24, no. 2, pp. 558-564, 2005. online
- K. Hollaus, O. Bíró, P. Caldera, G. Matzenauer, G. Paoli, K. Preis, B. Weiss, "Simulation of Simple Topologies on a PCB by a Frequency and a Time Domain Method," Proceedings of Joint 9th ICEAA `05 and 11th EESC `05, Torino, Italy, 12th Sept. – 16th Sept. 2005, ISBN 88-8202-094-0, pp. 893-896.preprint
- K. Hollaus, O. Bíró, "Comparison of Tetrahedral Edge Finite-Elements Using Different Potential Formulations,” IEEE Transactions on Magnetics, vol. 41, pp. 1676-1679, May 2005. online
- K. Hollaus, O. Bíró, C. Gerstenberger, K. Preis, R. Stollberger, B. Wagner, "Effect of Stray Capacitances on Bio-Impedances in Quasi-Static Electric Field,” IEEE Transactions on Magnetics, vol. 41, pp. 1940-1943, May 2005. online
- R. Merwa, K. Hollaus, P. Brunner, H. Scharfetter, "Solution of the inverse problem of magnetic induction tomography (MIT)", Physiol. Meas., vol. 26, no. 2, pp. S241-S250, April 2005. online
- K. Hollaus, C. Gerstenberger, C. Magele, H. Hutten, "Accurate Reconstruction Algorithm of the Complex Conductivity Distribution in Three Dimensions," IEEE Transactions on Magnetics, vol. 40, pp. 1144-1147, March 2004. online
- K. Hollaus, C. Magele, R. Merwa, H. Scharfetter, "Numerical Simulation of the Eddy Current Problem in Magnetic Induction Tomography for Biomedical Applications by Edge Elements,” IEEE Transactions on Magnetics, vol. 40, pp. 623-626, March 2004. online
- K. Hollaus, C. Magele, R. Merwa, H. Scharfetter, "Fast calculation of the sensitivity matrix in magnetic induction tomography by tetrahedral edge finite elements and the reciprocity theorem", Physiol. Meas., vol. 25, no. 1, pp. 159-168, February 2004. online
- K. Hollaus, B. Weiß, Ch. Magele, H. Hutten, "Geometric multigrid to accelerate the solution of the quasi-static electric field problem by tetrahedral finite elements", Physiol. Meas., vol. 25, no. 1, pp. 169-179, February 2004. online
- R. Casañas, H. Scharfetter, A. Altes, A. Remacha, P. Sarda, J. Sierra, R. Merwa, K. Hollaus, J. Rosell, "Measurement of liver iron overload by magnetic induction using a planar gradiometer: preliminary human results", Physiol. Meas., vol. 25, no. 1, pp. 315-323, February 2004. online
- H. Scharfetter, S. Rauchenzauner, R. Merwa, O. Bíró, K. Hollaus, "Planar gradiometer for magnetic induction tomography (MIT): theoretical and experimental sensitivity maps for a low-contrast phantom", Physiol. Meas., vol. 25, no. 1, pp. 325-333, February 2004. online
- R. Merwa, K. Hollaus, O. Bíró, H. Scharfetter, "Detection of brain oedema using magnetic induction tomography: A feasibility study of the likely sensitivity and detectability", Physiol. Meas., vol. 25, no. 1, pp. 347-354, February 2004. online
- R. Casañas, H. Scharfetter, A. Altes, A. Remacha, P. Sarda, J. Sierra, R. Merwa, K. Hollaus, J. Rosell, "In-vitro and in-vivo measurement of iron concentration in human hepatic tissue by magnetic induction methods," Proc. 25th Annual Int. Conf. IEEE, Eng. in Med. and Biol. Society, vol. 4, pp. 3064-3067, Sept. 2003. online
- K. Hollaus, R. Stollberger, B. Wagner, C. Gerstenberger, Ch. Magele, H. Hutten, "Simulations of the bio-impedance of the human thigh by the finite element method in 3D", Tagungsband des 48. Internationalen Wissenschaftliches Kolloquium der TU Ilmenau, ISSN 1619-4098, pp. 425-426, Ilmenau, Germany, 22-25, September 2003. preprint
- R. Merwa, K. Hollaus, B. Brandstätter, H. Scharfetter, "Numerical solution of the general 3D eddy current problem for magnetic induction tomography (spectroscopy)", Physiol. Meas., vol. 24, no. 2, pp. 545-554, May 2003. online
- B. Brandstätter, K. Hollaus, Ch. Magele, M. Michael, R. Merwa, H. Scharfetter, H. Hutten, "Direct estimation of Cole parameters in multifrequency EIT using a regularized Gauss-Newton method", Physiol. Meas., vol. 24, no. 2, pp. 437-448, May 2003. online
- K. Hollaus, O. Bíró, B. Brandstätter, S. P. Cermak, H. Zangl, G. Brasseur, "Design and Optimization of a Multi-Induction-Loop Access Control System", Proceedings of the International Symposium on Electromagnetic Compatibility, EMC Europe 2002, vol. 2, pp. 883-888, Sorrent, Italy, September 9-13, 2002. preprint
- K. Hollaus, O. Bíró, "Derivation of a Complex Permeability from the Preisach Model," IEEE Transactions on Magnetics, vol. 38, pp. 905-908, March 2002. online
- D. Rodger, P. C. Coles, O. Bíró, K. Hollaus, J. Pávó, "An Aluminium Plate Benchmark for ECT", in Electromagnetic Nondestructive Evaluation (V), eds. J. Pávó et al, IOS Press, Amsterdam, vol. 21, pp. 46-48, 2001. online
- O. Bíró, K. Hollaus, J. Pávó and K. Preis, "Numerical computation of the magnetic field due to a crack in a conducting plate", in Electromagnetic Nondestructive Evaluation (V), eds. J. Pávó et al, IOS Press, Amsterdam, vol. 21, pp. 11-15, 2001. online
- J. Pávó, O. Bíró, K. Hollaus, "Calculation of the field map from the measurement data of the fluxset sensor", COMPEL, vol. 20, no. 2, pp. 404-416, 2001. online
- K. Hollaus, O. Bíró, "A FEM of the Eddy Current Losses in Thin Ferromagnetic Sheets", Proceedings of the 9th International IGTE Symposium on Numerical Field Calculation in Electrical Engineering, pp. 152-157, Graz, Austria, September 11-13, 2000. preprint
- K. Hollaus, O. Bíró, "A FEM Formulation to Treat 3D Eddy Currents in Laminations," IEEE Transactions on Magnetics, vol. 36, pp. 1289-1292, July 2000. online
- D. Rodger, P. C. Coles, O. Bíró, K. Hollaus, J. Pávó, "An Aluminium Plate Benchmark for ECT", in Short Papers of The Sixth International Workshop on Electromagnetic Nondestructive Evaluation, ISBN 9-634206-42-5, Budapest, Hungary, pp. 39-40, 28th-30th July, 2000.
- O. Bíró, K. Hollaus, J. Pávó and K. Preis, "Numerical computation of the magnetic field due to a crack in a conducting plate", in Short Papers of The Sixth International Workshop on Electromagnetic Nondestructive Evaluation, ISBN 9-634206-42-5, Budapest, Hungary, pp. 7-8, 28th-30th July, 2000.
- K. Hollaus, O. Bíró, "Estimation of 3-D eddy currents in conducting laminations by an anisotropic conductivity and a 1-D analytical solution", COMPEL, vol. 18, no. 3, pp. 494-503, 1999. online