
Publications
Journal Papers
 W. C. Chew and L. Gürel, “Reflection and transmission
operators for strips or disks embedded in homogeneous and layered media,” IEEE Trans. Microwave Theory Tech., vol. MTT36, pp. 14881497, Nov. 1988.
 L. Gürel and W. C. Chew, “Guidance or resonance conditions for strips or disks embedded in homogeneous and layered media,” IEEE Trans. Microwave Theory Tech., vol. MTT36, pp. 14981506, Nov. 1988.
 L. Gürel and W. C. Chew, “Recursive algorithms for
calculating the scattering from N strips or patches,” IEEE
Trans. Antennas Propagat.vol. AP38, pp. 507515, Apr.
1990.
 L. Gürel and W. C. Chew, “A recursive Tmatrix algorithm
for strips and patches,” Radio Science, vol. 27,pp. 387401,
MayJune 1992.
 W. C. Chew, L. Gürel, Y. M. Wang, G. Otto, R. Wagner, and Q. H.
Liu, “A generalized recursive algorithm for wavescattering solutions in
two dimensions,” IEEE Trans. Microwave Theory Tech.,
vol. MTT40, pp.
716723, April 1992.
 W. C. Chew, Y. M. Wang, and L. Gürel, “Recursive algorithm
for using windowed addition theorem,” J. of Electromagn. Waves Appl., vol. 6,no. 11, pp. 15371560, Nov. 1992.
 L. Gürel and W. C. Chew, “Scattering solution of threedimensional array of patches using the recursive Tmatrix algorithms,” IEEE Microwave and Guided Wave Lett., vol. 2, pp. 182184, May 1992.
 L. Gürel and W. C. Chew, “Recursive Tmatrix algorithms for the solution of electromagnetic scattering from strip and patch geometries,” IEEE Trans. Antennas Propagat.,vol. AP41, pp. 9199, Jan. 1993.
 L. Gürel and M. I. Aksun, “Electromagnetic scattering solution of conducting strips in layered media using the fast multipole method,” IEEE Microwave and Guided Wave Lett. vol. 6, no. 8, pp. 277279, Aug. 1996.
 U. Oğuz and L. Gürel, “Interpolation techniques to improve the accuracy of the plane wave excitations in the finite difference time domain method,” Radio Science vol. 32, no. 6, pp. 21892199, Nov.Dec. 1997.
 L. Gürel and W. C. Chew, “Fast algorithm for scattering from planar arrays of conducting patches,” IEEE Microwave and Guided Wave Lett., vol. 8, no. 4, pp. 155157, April 1998.
 U. Oğuz, L. Gürel and O. Arıkan, “An efficient and accurate technique for the incidentwave excitations in the FDTD method,” IEEE Trans. Microwave Theory Tech., vol. 46, no. 6, pp. 869882, June 1998.
 L. Gürel, K. Sertel, and İ. K. Şendur, “On the choice of basis functions to model surface electric current densities in computational electromagnetics,” Radio Science, vol. 34, no. 6, pp. 13731387, Nov.Dec. 1999.
 L. Gürel and U. Oğuz, “Signalprocessing techniques to
reduce the sinusoidal steadystate error in the FDTD method,” IEEE
Trans. Antennas Propagat. vol. 48, no. 4, pp. 585593, April 2000.
 L. Gürel and U. Oğuz, “Threedimensional FDTD modeling
of a groundpenetrating radar,” IEEE Trans. Geosci. Remote Sensing,
vol. 38, no. 4, pp. 15131521, July 2000.
 L. Gürel and U. Oğuz, “Simulations of groundpenetrating
radars over lossy and heterogeneous grounds,” IEEE Trans. Geosci.
Remote Sensing, vol. 39, no. 6, pp. 11901197, June
2001.
 U. Oğuz and L. Gürel, “Modeling of
groundpenetratingradar antennas with shields and simulated absorbers,” IEEE
Trans. Antennas Propagat, vol. 49, no. 11, pp. 15601567, Nov. 2001.
 M. I. Aksun, F. Caliskan, and L. Gürel, “An efficient method for electromagnetic characterization of 2D geometries in stratified media,” IEEE Trans. Microwave Theory Tech., vol. 50, no. 5, pp. 12641274, May 2002.
 L. Gürel and U. Oğuz,
“Transmitterreceivertransmitter configurations of the groundpenetrating
radar,” Radio Science, vol. 37, no.3, pp. 51  57, May
2002.
 U. Oğuz and L. Gürel, "Application
of signalprocessing techniques to dipole excitations in the finitedifference
timedomain method," J. Electromagn. Waves Appl.vol.
16, no. 5, pp. 671687, May 2002.
 U. Oğuz and L. Gürel, "Frequency
responses of groundpenetrating radars operating over highly lossy grounds,"
IEEE Trans. Geosci. Remote Sensingvol. 40, no. 6, pp. 13851394, June 2002.
 L. Gürel and U. Oğuz, "Transmitterreceivertransmitterconfigured
groundpenetrating radars over randomly heterogeneous ground models,"
Radio Science, vol. 37, no. 6, pp. 61  69, Nov.Dec. 2002.
 U. Oğuz and L. Gürel, "Optimization of the
transmitterreceiver separation in the groundpenetrating radar," IEEE Trans. Antennas Propagat., vol. 51, no. 3, pp. 362370, Mar. 2003.
 L. Gürel, H. Bağcı, J. C. Castelli,
A. Cheraly, and F. Tardivel, "Validation through comparison: measurement
and calculation of the bistatic radar cross section (BRCS) of a stealth
target," Radio Science, vol. 38,
no. 3, pp. 121  1210, June 2003.
 U. Oğuz and L. Gürel, "Reducing the
dispersion errors of the finitedifference timedomain method for
multifrequency planewave excitations," Electromagnetics, vol. 23,
no. 6, pp. 539  552, Aug.Sep. 2003.
 Ö. Ergül and L. Gürel, "Nonplanar trapezoidaltooth logperiodic antennas: design and electromagnetic modelling,"
Radio Science, vol. 40, RS5010, doi:10.1029/2004RS003215, Oct. 2005.
 Ö. Ergül and L. Gürel, "Solidangle factor in the magneticfield integral equation," Microwave and Opt. Technol. Lett., vol. 45, no. 5, pp. 452456, June 2005.
 L. Gürel and Ö. Ergül, "Singularity of the magneticfield integral equation and its extraction," IEEE Antennas Wireless Propagat. Lett., vol. 4, pp. 229232, 2005.
 Ö. Ergül and L. Gürel, "Improved testing of the magneticfield integral equation," IEEE Microwave Wireless Comp. Lett., vol. 15, no. 10, pp. 615617, Oct. 2005.
 Ö. Ergül and L. Gürel, "The use of curlconforming basis functions for the magneticfield integral equation," IEEE Trans. Antennas Propagat., vol. 54, no. 7, pp. 19171926, July 2006.
 Ö. Ergül and L. Gürel, "Improving the accuracy of the magneticfield integral equation with the linearlinear basis functions," Radio Sci., vol. 41, RS4004, doi:10.1029/2005RS003307, July 2006.
 Ö. Ergül and L. Gürel, "Enhancing the accuracy of the interpolations and anterpolations in MLFMA," IEEE Antennas Wireless Propagat. Lett., vol. 5, pp. 467470, 2006.
 Ö. Ergül and L. Gürel, "Optimal interpolation of translation operator in multilevel fast multipole algorithm," IEEE Trans. Antennas Propagat., vol. 54, no. 12, pp. 38223826, Dec. 2006.
 L. Gürel and Ö. Ergül, "Extending the applicability of the combinedfield integral equation to geometries containing open surfaces," IEEE Antennas Wireless Propagat. Lett., vol. 5, pp. 515516, 2006.
 Ö. Ergül and L. Gürel, "Linearlinear basis functions for MLFMA solutions of magneticfield and combinedfield integral equations," IEEE Trans. Antennas Propagat., vol. 55, no. 4, pp. 11031110, Apr. 2007.
 T. Malas and L. Gürel, "Incomplete LU preconditioning with multilevel fast multipole algorithm for electromagnetic scattering," SIAM J. Scientific Computing, vol. 29 , no. 4, pp. 14761494, June 2007.
 Ö. Ergül and L. Gürel, "Modeling and synthesis of circularsectoral arrays of logperiodic antennas using multilevel fast multipole algorithm and genetic algorithms," Radio Science, vol. 42, RS3018, doi:10.1029/2006RS003567, June 2007.
 L. Gürel and Ö. Ergül, "Fast and accurate solutions of extremely large integralequation problems discretized with tens of millions of unknowns," Electron. Lett., vol. 43, no. 9, pp. 499500, doi:10.1049/el:20070639, Apr. 2007.
 Ö. Ergül and L. Gürel, "Efficient solution of the electricfield integral equation by the iterative LSQR algorithm," IEEE Antennas Wireless Propagat. Lett., vol. 7, pp. 3639, 2008.
 Ö. Ergül and L. Gürel, "Hierarchical parallelisation strategy for the multilevel fast multipole algorithm in computational electromagnetics," Electron. Lett., vol. 44, no. 1, pp. 35, Mar2008.
 Ö. Ergül and L. Gürel, "Stabilization of integralequation formulations for the accurate solution of scattering problems involving lowcontrast dielectric objects," IEEE Trans. Antennas Propagat., vol. 56, pp. 799805, 2008.
 Ö. Ergül and L. Gürel, "Efficient parallelization of the multilevel fast multipole algorithm for the solution of largescale scattering problems," IEEE Trans. Antennas Propagat., vol. 56, no. 8, pp. 23352345, Aug. 2008.
 Ö. Ergül and L. Gürel, "Novel electromagnetic surface integral equations for highly accurate computations of dielectric bodies with arbitrarily low contrasts," J. Comput. Phys., vol. 227, no. 23, pp. 98989912, Dec. 2008.
 L. Gürel and Ö. Ergül, "Design and simulation of circular arrays of trapezoidaltooth logperiodic antennas via genetic optimization," Prog. Electromagn. Res., PIER 85, pp. 243260, 2008.
 Ö. Ergül and L. Gürel, "Comparison of integralequation formulations for the fast and accurate solution of scattering problems involving dielectric objects with the multilevel fast multipole algorithm," IEEE Trans. Antennas Propagat., vol. 57, no. 1, pp. 176187, Jan. 2009.
 T. Malas and L. Gürel, "Accelerating the multilevel fast multipole algorithm with the sparseapproximateinverse (SAI) preconditioning," SIAM J. Sci. Comput., vol. 31, no.3, pp. 19681984, March 2009.
 Ö. Ergül, I. van den Bosch, and L. Gürel, "Twostep Lagrange interpolation method for the multilevel fast multipole algorithm," IEEE Antennas Wireless Propagat. Lett., vol. 8, pp. 6971, 2009.
 Ö. Ergül and L. Gürel, "Iterative solutions of hybrid integral equations for coexisting open and closed surfaces," IEEE Trans. Antennas Propagat., vol. 57, no. 6, pp. 1751–1758, June 2009.
 Ö. Ergül and L. Gürel, "A hierarchical partitioning strategy for an efficient parallelization of the multilevel fast multipole algorithm," IEEE Trans. Antennas Propagat., vol. 57, no. 6, pp. 1740–1750, June 2009.
 L. Gürel, Ö. Ergül, A. Ünal, and T. Malas "Fast and accurate analysis of large metamaterial structures using the multilevel fast multipole algorithm," Prog. Electromagn. Res., PIER 95, pp 179198, 2009.
 L. Gürel and Ö. Ergül, "Contamination of the accuracy of the combinedfield integral equation with the discretization error of the magneticfield integral equation," IEEE Trans. Antennas Propagat., vol. 57, no. 9, pp. 2650–2657, Sept. 2009.
 Ö. Ergül and L. Gürel, "Discretization error due to the identity operator in surface integral equations," Comput. Phys. Commun., vol. 180, no. 10, pp. 17461752, Oct 2009.
 Ö. Ergül and L. Gürel, "Efficient solution of the electric and magnetic current combinedfield integral equation with the multilevel fast multipole algorithm and blockdiagonal preconditioning," Radio Science, vol. 44, RS6001, doi:10.1029/2009RS004143.
 L. Gürel and T. Malas, "Iterative nearfield preconditioner for the multilevel fast multipole algorithm," SIAM J. Sci. Comput., vol. 32, no. 4, pp. 1929–1949, 2010.
 Ö. Ergül, A. ArslanErgül and L. Gürel, "Computational study of scattering from healthy and diseased red blood cells," J. Biomed. Opt., vol. 15, no. 4, 045004, doi:10.1117/1.3467493, July/Aug. 2010.
 Ö. Ergül, T. Malas and L. Gürel, "Solutions of largescale electromagnetics problems using an iterative innerouter scheme with ordinary and approximate multilevel fast multipole algorithms," Prog. Electromagn. Res., PIER 85, vol. 106, pp. 203223, 2010.
 Ö. Ergül and L. Gürel, "Efficient solutions of metamaterial problems using a lowfrequency multilevel fast multipole algorithm," Prog. Electromagn. Res., vol. 108, no. 8199, 2010.
 Ö. Ergül and L. Gürel, "Improving iterative solutions of the electricfield integral equation via transformations into normal equations," J. of Electromagn. Waves and Appl., vol. 24, no. 16, pp. 2129–2138, Nov. 2010.
 Ö. Ergül and L. Gürel, "Rigorous solutions of electromagnetics problems involving hundreds of millions of unknowns," IEEE Antennas Propagat. Mag., vol. 53, no. 1, pp. 1827, Feb. 2011.
 Ö. Ergül, T. Malas, and L. Gürel, "Analysis of dielectric photoniccrystal problems with MLFMA and Schurcomplement preconditioners," J. Lightw. Technol., vol. 29, no. 6, pp. 888897, Mar. 2011.
 T. Malas and L. Gürel, "Schur complement preconditioners for surface integralequation formulations of dielectric problems solved with the multilevel fast multipole algorithm," SIAM J. Sci. Comput., vol. 33, no. 5, pp. 2440–2467, 2011.
 Ö. Ergül and L. Gürel, "Rigorous analysis of doublenegative materials with the multilevel fast multipole algorithm," Applied Computational Electromagnetics Society (ACES) Journal, vol. 27, no. 2, pp. 161168, Feb. 2012.
 L. Gürel and Ö. Ergül, "Hierarchical parallelization of the multilevel fast multipole algorithm (MLFMA)," IEEE Proceedings, , vol. 101, no. 2, pp. 332  341, Feb. 2013.
 Ö. Ergül and L. Gürel, "Accurate solutions of extremely large integralequation problems in computational electromagnetics," IEEE Proceedings, , vol. 101, no. 2, pp. 342  349, Feb. 2013.
 Ö. Ergül and L. Gürel, "Fast and Accurate Analysis of LargeScale Composite Structures with the Parallel Multilevel Fast Multipole Algorithm," J. Opt. Soc. Am. A, vol. 30, no. 3, pp. 509  517, March 2013.
Conference Papers
 W. C. Chew and L. Gürel, "Reflection and transmission operators for strips or disks embedded in homogeneous and layered media," 1988 URSI Radio Science Meeting Digest, Syracuse, NY, p. 312, June 1988.
 L. Gürel and W. C. Chew, "Guidance or resonance conditions for strips or disks embedded in homogeneous and layered media," 1988 URSI Radio Science Meeting Digest, Syracuse, NY, p. 320, June 1988.
 W. C. Chew and L. Gürel, "Recursive algorithms for calculating the scattering from N strips or disks," 1989 URSI Radio Science Meeting, Program and Abstracts, San Jose, CA, p. 220, June 1989.
 W. C. Chew and L. Gürel, "An O(N 2) recursive algorithm for calculating the scattering from strips or patches," 1990 URSI Radio Science Meeting, Program and Abstracts, Dallas, TX, p. 5, May 1990.
 W. C. Chew, Y. M. Wang, L. Gürel, and J. H. Lin, "Recursive algorithms to reduce the computational complexity of scattering problems," The 7th Annual Review of Progress in Applied Computational Electromagnetics, Conference Proceedings, Monterey, CA, pp. 278291, Mar. 1991.
 L. Gürel and W. C. Chew, "On the connection of T matrices and integral equations," 1991 International IEEE APS Symposium Digest, London, Ontario, Canada, June 1991.
 L. Gürel and W. C. Chew, "Recursive Tmatrix algorithms for 1D and 2D clusterings of strips," 1991 International IEEE APS Symposium Digest, London, Ontario, Canada, June 1991.
 L. Gürel and W. C. Chew, "Recursive Tmatrix algorithms for conducting patches," 1991 North American Radio Science Meeting, Program and Abstracts, London, Ontario, Canada, June 1991.
 W. C. Chew, Y. M. Wang, L. Gürel, J. H. Lin, and Q. H. Liu, "Fast algorithms for calculating scattering by inhomogeneous and impenetrable objects," Progress in Electromagnetics Research Symposium Proceedings, Cambridge, MA, p. 699, July 1991.
 W. C. Chew, Y. M. Wang, and L. Gürel, "A recursive algorithm using windowed addition theorem," 1992 IEEE APS International Symposium Digest, Chicago, IL, pp. 15871590, July 1992.
 L. Gürel, "Fast algorithm for electromagnetic solution of modifiedgeometry problems," 1993 IEEE APS International Symposium Digest, Ann Arbor, MI, pp. 6063, June 1993.
 L. Gürel and T. Gürel, "Absorbing boundary condition for monochromatic oblique incidence," Progress in Electromagnetics Research Symposium Proceedings, Pasadena, CA, p. 118, July 1993.
 L. Gürel, S. Daijavad, and B. J. Rubin, "Investigation of the resonances of open rectangular cavities," 1994 URSI Radio Science Meeting, Seattle, WA, June 1994.
 L. Gürel, "Fastmultipolemethod solution of twodimensional conductor geometries," 1995 IEEE APS International Symposium and URSI Radio Science Meeting, Newport Beach, CA, June 1995.
 L. Gürel, "Computational electromagnetics, electromagnetic compatibility and European Community," in Turkish, 6. National Symposium of Electrical Engineering, Bursa, Turkey, Sept. 1995.
 L. Gürel and M. I. Aksun, "Fast multipole method in layered media: 2D electromagnetic scattering problems," 1996 IEEE APS International Symposium and URSI Radio Science Meeting, Baltimore, MD, July 1996.
 L. Gürel, "Fast RCS computation via the fast multipole method," NATO AGARD SPP Symposium on Radar Signature Analysis and Imaging of Military Targets, Ankara, Turkey, Oct. 1996.
 L. Gürel, "Electromagnetic compatibility and computational electromagnetics," in Turkish, Symposium for the Technological Progress in the Defense Industry, Ankara, Turkey, June 1997.
 L. Gürel, "Electromagnetic modeling of the GPR (ground penetrating radar) and scenario simulations," in Turkish, Symposium for the Technological Progress in the Defense Industry, Ankara, Turkey, June 1997.
 L. Gürel, "Fast algorithms for the RCS computations of complex and large targets," in Turkish, Symposium for the Technological Progress in the Defense Industry, Ankara, Turkey, June 1997.
 İ. K. Şendur and L. Gürel, "FMM solution of large threedimensional electromagnetics problems with arbitrary surface triangulations," Progress in Electromagnetics Research Symposium, Cambridge, MA, July 1997.
 K. Sertel and L. Gürel, "FMM solution of electromagnetic scattering problems involving curved surfaces," Progress in Electromagnetics Research Symposium, Cambridge, MA, July 1997.
 L. Gürel, U. Oğuz, and O. Arıkan, "Accurate planewave excitation in the FDTD method," 1997 IEEE APS International Symposium and URSI Radio Science Meeting, Montreal, Canada, July 1997.
 U. Oğuz and L. Gürel, "Subsurfacescattering calculations via the 3D FDTD method employing PML ABC for layered media," 1997 IEEE APS International Symposium and URSI Radio Science Meeting, Montreal, Canada, July 1997.
 L. Gürel and W. C. Chew, "Fast direct solution algorithm for electromagnetic scattering from 3D planar and quasiplanar geometries," 1997 IEEE APS International Symposium and URSI Radio Science Meeting, Montreal, Canada, July 1997.
 L. Gürel, İ. K. Şendur, and K. Sertel, "Quantitative comparison of rooftop and RWG basis functions," 1997 IEEE APS International Symposium and URSI Radio Science Meeting, Montreal, Canada, July 1997.
 K. Sertel and L. Gürel, "A comparison of surfacemodeling techniques," 1997 IEEE APS International Symposium and URSI Radio Science Meeting, Montreal, Canada, July 1997.
 İ. K. Şendur and L. Gürel, "Solution of radiation problems using the fast multipole method," 1997 IEEE APS International Symposium and URSI Radio Science Meeting, Montreal, Canada, July 1997.
 L. Gürel and W. C. Chew, "Fast direct (noniterative) solvers for integralequation formulations of scattering problems," 1998 IEEE APS International Symposium and URSI North American Radio Science Meeting, Atlanta, GA, June 1998.
 L. Gürel and W. C. Chew, "Fast noniterative steepest descent path algorithm for planar and quasiplanar patch geometries," 1998 IEEE APS International Symposium and URSI North American Radio Science Meeting, Atlanta, GA, June 1998.
 F. Çalışkan, M. I. Aksun, and L. Gürel, "Efficient methods for electromagnetic characterization of 2D geometries in stratified media," 1998 IEEE APS International Symposium and URSI North American Radio Science Meeting, Atlanta, GA, June 1998.
 L. Gürel, Kubilay Sertel, and İbrahim Kürş at Şendur, "On the chargemodeling capabilities of a class of current basis functions," Progress in Electromagnetics Research Symposium, Nantes, France, July 1998.
 L. Gürel and İ. K. Şendur, "Computational investigation of radiation from conducting boxes with arbitrary apertures," International Symposium on Electromagnetic Compatibility, Rome, Italy, Sept. 1998.
 L. Gürel, A. E. Yılmaz, and W. C. Chew, "Fast computation of scattering from (near)resonant structures," Proceedings of the 1999 IEEE APS International Symposium and USNC/URSI National Radio Science Meeting, pp. 11741177, Orlando, Florida, USA, July 1999.
 L. Gürel and U. Oğuz, "Employing PML absorbers in the design and simulation of ground penetrating radars," Proceedings of the 1999 IEEE APS International Symposium and USNC/URSI National Radio Science Meeting, pp. 18901893, Orlando, Florida, USA, July 1999.
 L. Gürel, "Electromagnetic compatibility standards and computer simulations," in Turkish, Proceedings of the 1999 Symposium of Effects of Electromagnetic Pollution, pp. 6164, Ankara, Turkey, Nov. 1999.
 L. Gürel and U. Oğuz, "Simulation of realistic threedimensional GPR scenarios using the FDTD method," Progress in Electromagnetics Research Symposium, Cambridge, Massachusetts, USA, July 2000.
 U. Oğuz and L. Gürel, "Threedimensional FDTD modeling of a GPR," Proceedings of the 2000 IEEE APS International Symposium and USNC/URSI National Radio Science Meeting, Salt Lake City, Utah, USA, July 2000.
 L. Gürel, "Radar cross section (RCS) computation of military targets and development of invisibility (stealth) techniques," in Turkish, National Defense Industry Symposium, Ankara, Turkey, Nov. 2000.
 U. Oğuz and L. Gürel, "Electromagnetic modeling of mine detection systems," in Turkish, National Defense Industry Symposium, Ankara , Turkey, Nov. 2000.
 L. Gürel, "Electromagnetic compatibility (EMC) in defense systems and EMC education," in Turkish, National Defense Industry Symposium, Ankara, Turkey, Nov. 2000.
 L. Gürel and Ö. Ergül, "Design of broadband logperiodic antenna arrays using genetic algorithms," in Turkish, Space Symposium: Global Space Activities and Potential in Turkey, Ankara, Turkey, pp. 411416, May 2001.
 L. Gürel and H. Bağcı, "The use of RCS computations in developing and precluding stealth techniques and radar design," in Turkish, Space Symposium: Global Space Activities and Potential in Turkey, Ankara , Turkey , pp. 443449, May 2001.
 L. Gürel and U. Oğuz, "Design and electromagnetic modelling of radars detecting land mines," in Turkish, Space Symposium: Global Space Activities and Potential in Turkey, Ankara, Turkey, pp. 403410, May 2001.
 L Gürel, "The importance of electromagnetic compatibility (EMC) in military systems and EMC education," in Turkish, Space Symposium: Global Space Activities and Potential in Turkey, Ankara, Turkey, pp. 395402, May 2001.
 U. Oğuz and L. Gürel, "On the frequencyband selection for groundpenetrating radars operating over lossy and heterogeneous grounds," 2001 IEEE APS International Symposium and USNC/URSI National Radio Science Meeting, Boston, Massachusetts, USA, July 2001.
 U. Oğuz and L. Gürel, "Simulation of TRTconfigured groundpenetrating radars over heterogeneous grounds," 2001 IEEE APS International Symposium and USNC/URSI National Radio Science Meeting, Boston, Massachusetts, USA, July 2001.
 L. Gürel and U. Oğuz, "Application of signalprocessing techniques to reduce the errors related to the FDTD excitations," 2001 IEEE APS International Symposium and USNC/URSI National Radio Science Meeting, Boston, Massachusetts, USA, July 2001.
 L. Gürel and H. Bağcı, "FMM computation of the bistatic RCS of stealth and nonstealth targets," 2002 IEEE APS International Symposium and URSI National Radio Science Meeting, San Antonio, Texas, USA, June 2002.
 Ö. Ergül and L. Gürel "Electricfield, magneticfield, and combinedfield integral equations for electromagnetic scattering problems," in Turkish, URSITurkey2002 Scientific Conference and National General Assembly Meeting, İstanbul Technical University, İstanbul, Turkey, pp. 158161, Sept. 2002.
 Ö. Ergül and L. Gürel, "Broadband logperiodic antennaarray design using genetic algorithms in an electromagnetic simulation environment," in Turkish, URSITurkey2002 Scientific Conference and National General Assembly Meeting, İstanbul Technical University, İstanbul, Turkey,pp. 154157, Sept. 2002.
 L. Gürel, "Electromagnetic compatibility simulations," in Turkish, URSITurkey2002 Scientific Conference and National General Assembly Meeting, İstanbul Technical University, İstanbul, Turkey, Sept. 2002.
 L. Gürel and U. Oğuz, "Electromagnetic simulations of groundpenetrating radars," in Turkish, URSITurkey2002 Scientific Conference and National General Assembly Meeting, İstanbul Technical University, İstanbul, Turkey, Sept. 2002.
 C. Cengiz Yıldırım and L. Gürel, "Electromagnetic method of moments in the presence of an infinitely large conducting plane," in Turkish, URSITurkey2002 Scientific Conference and National General Assembly Meeting, İstanbul Technical University, İstanbul, Turkey, Sept. 2002.
 Ö. Ergül and L. Gürel, "Solution of the electromagnetic scattering problems with the fast multipole method," in Turkish, High Performance Computing Symposium, Gebze Institute of Technology, Kocaeli, Turkey, Oct. 2002.
 L. Gürel, "Domestic R&D contributions for national defense projects," in Turkish, Symposium on Strategic Relations in the Defense Industry, Ankara, Turkey, Nov. 2002.
 L. Gürel, Ö. Ergül, and H. Bağcı, "Computation of the bistatic RCS of stealth airborne targets via the fast multipole method," PIERS 2003 Progress in Electromagnetics Research Symposium, Singapore , Jan. 2003.
 L. Gürel, "Electromagnetic modelling and simulation," in Turkish, Symposium: Modelling and Simulation for Defense Applications, Ankara, Turkey, May 2003.
 U. Oğuz and L. Gürel, "FDTD simulations of multiple GPR systems," 2003 IEEE APS International Symposium and USNC/CNC/URSI National Radio Science Meeting, Columbus, Ohio, June 2003.
 Ö. Ergül and L. Gürel, "Logperiodic antenna design using electromagnetic simulations," 2003 IEEE APS International Symposium and USNC/CNC/URSI National Radio Science Meeting, Columbus, Ohio, vol. 1, pp. 245248, June 2003.
 Ö. Ergül and L. Gürel, "Comparisons of FMM implementations employing different formulations and iterative solvers," 2003 IEEE APS International Symposium and USNC/CNC/URSI National Radio Science Meeting, Columbus, Ohio, vol. 1, pp. 1922, June 2003.
 L. Gürel and U. Oğuz, "Threedimensional electromagnetic modeling of various GPR problems," PIERS 2003 Progress in Electromagnetics Research Symposium, Honolulu, Hawaii, USA, Oct. 2003.
 L. Gürel and Ö. Ergül, "EFIE, MFIE, and CFIE solutions of electromagnetic scattering problems," PIERS 2003 Progress in Electromagnetics Research Symposium, Honolulu, Hawaii, USA, Oct. 2003.
 L. Gürel, "3D FDTD simulations of ground penetrating radar scenarios," PIERS 2004 Progress in Electromagnetics Research Symposium, Pisa , Italy , Mar. 2004.
 Ö. Ergül and L. Gürel, "Investigation of the inaccuracy of the MFIE discretized with the RWG basis functions," 2004 IEEE APS International Symposium and URSI Radio Science Meeting, Monterey, CA, vol. 3, pp. 33933396, June 2004.
 Ö. Ergül and L. Gürel, "Improving of the accuracy of the MFIE with the choice of basis functions," 2004 IEEE APS International Symposium and URSI Radio Science Meeting, Monterey, CA, vol. 3, pp. 33893392, June 2004.
 Ö. Ergül and L. Gürel, "Problems in the use of the RWG functions for the magneticfield integral equation," in Turkish, URSITurkey 2004 Scientific Symposium, Ankara, Turkey, pp. 7476, Sept. 2004.
 Ö. Ergül and L. Gürel, "The use of linear basis functions for the magneticfield integral equation," in Turkish, URSITurkey 2004 Scientific Symposium, Ankara , Turkey , pp. 9092, Sept. 2004.
 Ö. Ergül, A. R. Bozbulut, and L. Gürel, "Parallelization of the multilevel fast multipole method for the solution of large electromagnetic scattering problems," in Turkish, URSITurkey 2004 Scientific Symposium, Ankara, Turkey, pp. 7173, Sept. 2004.
 F. Yıldırım and L. Gürel, "Extrapolation of frequency domain solution of electromagnetic problems with matrix pencil method," in Turkish, URSITurkey 2004 Scientific Symposium, Ankara, Turkey, Sept. 2004.
 L. Gürel and T. Malas, "Algebraic properties of preconditioned dense linear systems arising in computational electromagnetics," SIAM Conference on Computational Science and Engineering, Orlando, Florida, USA, Feb. 2005.
 Ö. Ergül and L. Gürel, "Combinedfield solution of composite geometries involving open and closed conducting surfaces," 2005 IEEE/ACES International Conference on Wireless Communications and Applied Computational Electromagnetics, Hawaii, USA, pp. 325328, April 2005.
 F. Yıldırım and L. Gürel, "Coupled matrix pencil method for frequency extrapolation of electromagnetic solutions," 2005 IEEE APS International Symposium and USNC/URSI National Radio Science Meeting, Washington , DC , USA , July 2005.
 L. Gürel and F. Yıldırım, "Coupled deconvolution for frequency extrapolation of electromagnetic solutions with matrix pencil method," 2005 IEEE APS International Symposium and USNC/URSI National Radio Science Meeting, Washington , DC , USA , July 2005.
 L. Gürel and Ö. Ergül, "Solution of large CEM problems with parallel multilevel fast multipole algorithm (MLFMA)," 2005 IEEE APS International Symposium and USNC/URSI National Radio Science Meeting, Washington , DC , USA , July 2005.
 Ö. Ergül and L. Gürel, "Iterative leastsquares solution of the combinedfield integral equation," 2005 IEEE APS International Symposium and USNC/URSI National Radio Science Meeting, Washington , DC , USA , July 2005.
 Ö. Ergül and L. Gürel, "Hybrid CFIEEFIE solution of composite geometries with coexisting open and closed surfaces," 2005 IEEE APS International Symposium and USNC/URSI National Radio Science Meeting, Washington, DC, USA, vol. 4B,. pp. 289292, July 2005.
 L. Gürel, Ö. Ergül, and T. Malas, "Preconditioned iterative solution of the combinedfield integral equation with the MLFMA," PIERS 2005 Progress in Electromagnetics Research Symposium, Hangzhou, China, Aug. 2005.
 Ö. Ergül and L. Gürel, "On the lagrange interpolation in multilevel fast multipole algorithm," 2006 IEEE APS International Symposium and USNC/URSI National Radio Science Meeting and AMEREM Meeting, Albuquerque, New Mexico, USA, pp. 18911894, July 2006.
 L. Gürel and Ö. Ergül, "Investigations of load balancing, communications, and scalability in parallel MLFMA," 2006 IEEE APS International Symposium and USNC/URSI National Radio Science Meeting and AMEREM Meeting, Albuquerque, New Mexico, USA, July 2006.
 Ö. Ergül and L. Gürel, "Design of circular logperiodic arrays using electromagnetic simulations," 2006 IEEE APS International Symposium and USNC/URSI National Radio Science Meeting and AMEREM Meeting, Albuquerque, New Mexico, USA, pp. 40234026, July 2006.
 L. Gürel and T. Malas, "Variable preconditioning with nested iterations employing MLFMA," 2006 IEEE APS International Symposium and USNC/URSI National Radio Science Meeting and AMEREM Meeting, Albuquerque, New Mexico, USA, July 2006.
 T. Malas and L. Gürel, "Incomplete LU preconditioning strategies for MLFMA," 2006 IEEE APS International Symposium and USNC/URSI National Radio Science Meeting and AMEREM Meeting, Albuquerque, New Mexico, USA, July 2006.
 L. Gürel, Ö. Ergül, and A. Ünal, "MLFMA modeling of metamaterials containing splitring resonators," 2006 IEEE APS International Symposium and USNC/URSI National Radio Science Meeting and AMEREM Meeting, Albuquerque, New Mexico, USA, July 2006.
 L. Gürel, Ö. Ergül, T. Malas, and A. Ünal, "Preconditioned parallel MLFMA solution of metamaterial structures," PIERS 2006 Progress in Electromagnetics Research Symposium, Tokyo, Japan, Aug. 2006.
 L. Gürel and Ö. Ergül, "Iterative solution of composite problems with the combinedfield integral equation," 36th European Microwave Conference 2006, Manchester, UK, pp. 239240, Sept. 2006.
 L. Gürel, A. Ünal, and Ö. Ergül, "Electromagnetic modeling of splitring resonators," 36th European Microwave Conference 2006, Manchester, UK, pp. 303305, Sept. 2006.
 Ö. Ergül and L. Gürel, "Efficient solutions of circular arrays of logperiodic antennas via the electricfield integral equation," in Turkish, URSITurkey 2006 Scientific Symposium, Ankara, Turkey, pp. 7678, Sept. 2006.
 Ö. Ergül and L. Gürel, "Leastsquares solution of the electricfield integral equation," in Turkish, URSITurkey 2006 Scientific Symposium, Ankara, Turkey, pp. 5254. Sept. 2006.
 Ö. Ergül and L. Gürel, "Investigation of integralequation formulations for iterative solutions of dielectric bodies," in Turkish, URSITurkey 2006 Scientific Symposium, Ankara, Turkey, pp. 4648. Sept. 2006.
 Ö. Ergül and L. Gürel, "Solution of composite geometries with open and closed surfaces via the hybridfield integral equation," in Turkish, URSITurkey 2006 Scientific Symposium, Ankara, Turkey, pp. 2224, Sept. 2006.
 Ö. Ergül, A. Ünal, and L. Gürel, "Electromagnetic simulation of large metamaterial structures," in Turkish, URSITurkey 2006 Scientific Symposium, Ankara, Turkey, pp. 376378, Sept. 2006.
 Ö. Ergül and L. Gürel, "Parallelization of the multilevel fast multipole algorithm for the solution of threedimensional arbitrary geometries," in Turkish, URSITurkey 2006 Scientific Symposium, Ankara, Turkey, pp. 4042, Sept. 2006.
 A. Manyas and L. Gürel, "Solution of highfrequency scattering problems of complex geometries via multilevel PO algorithm," in Turkish, URSITurkey 2006 Scientific Symposium, Ankara, Turkey, Sept. 2006.
 T. Malas and L. Gürel, "Using nested solvers as effective preconditioners in computational electromagnetics," in Turkish, URSITurkey 2006 Scientific Symposium, Ankara, Turkey, Sept. 2006.
 T. Malas and L. Gürel, "Incomplete LU preconditioners for surface integral equations," in Turkish, URSITurkey 2006 Scientific Symposium, Ankara, Turkey, Sept. 2006.
 T. Malas and L.Gürel, "A parallel sparse approximate inverse preconditioner for the multilevel fast multipole algorithm," in Turkish, URSITurkey 2006 Scientific Symposium, Ankara, Turkey, Sept. 2006.
 L. Gürel, Ö. Ergül, and T. Malas, "Parallel MLFMA solution of large integralequation problems," in Turkish, URSITurkey 2006 Scientific Symposium, Ankara, Turkey, pp. 3133, Sept. 2006.
 Ö. Ergül, F. Akdeniz, and L. Gürel, "Efficient and accurate electromagnetic simulation of doubleridged horn antennas with the multilevel fast multipole algorithm, in Turkish, URSITurkey 2006 Scientific Symposium, Ankara, Turkey, pp. 170172, Sept. 2006.
 Ö. Ergül, A. Ünal, and L. Gürel, "Efficient and accurate analysis of large metamaterial structures with the multilevel fast multipole algorithm," IV. International Workshop on Electromagnetic Wave Scattering, Gebze, Turkey, pp. 8.158.20, Sept. 2006.
 Ö. Ergül and L. Gürel, "Rigorous analysis of circular logperiodic arrays using the multilevel fast multipole algorithm," IV. International Workshop on Electromagnetic Wave Scattering, Gebze,Turkey, pp. 6.156.20, Sept. 2006.
 T. Malas and L. Gürel, "Effective preconditioning techniques for iterative solutions of integralequation methods," IV. International Workshop on Electromagnetic Wave Scattering, Gebze, Turkey, Sept. 2006.
 L. Gürel, Ö. Ergül, T. Malas, "Solutions of large problems of computational electromagnetics at Bilkent University," IV. International Workshop on Electromagnetic Wave Scattering, Gebze, Turkey, pp. 10.910.17, Sept. 2006.
 Ö. Ergül and L. Gürel, "On the accuracy of MFIE and CFIE in the solution of large electromagnetic scattering problems," European Conference on Antennas and Propagation (EuCAP 2006), Nice, France, Nov. 2006.
 Ö. Ergül and L. Gürel, "Circular arrays of logperiodic antennas for broadband applications, "European Conference on Antennas and Propagation (EuCAP 2006), Nice, France, Nov. 2006.
 Ö. Ergül and L. Gürel, "Efficient parallelization of multilevel fast multipole algorithm," European Conference on Antennas and Propagation (EuCAP 2006), Nice, France, Nov. 2006.
 Ö. Ergül, A. Ünal, and L. Gürel, "Accurate modeling of metamaterials with MLFMA," European Conference on Antennas and Propagation (EuCAP 2006), Nice, France, Nov. 2006.
 T. Malas and L. Gürel, "Incomplete LU preconditioning for the electricfield integral equation," European Conference on Antennas and Propagation (EuCAP 2006), Nice, France, Nov. 2006.
 A. Manyas and L. Gürel, "Multilevel PO algorithm for nonuniform triangulations," European Conference on Antennas and Propagation (EuCAP 2006), Nice, France, Nov. 2006.
 L. Gürel, T. Malas, and Ö. Ergül, "Preconditioning the MLFMA solution of EFIE with nested flexible iterative solvers," SIAM Conference on Computational Science and Engineering, Costa Mesa, California, USA, Feb. 2007.
 L. Gürel, Ö. Ergül, and A. Ünal, "Investigation of transmission properties of multilayer metamaterial structures with MLFMA," The 23rd International Review of Progress in Applied Computational Electromagnetics (ACES 2007), Verona, Italy, March 2007.
 L. Gürel, Ö. Ergül, and T. Malas, "Solutions of large integralequation problems with parallel preconditioned MLFMA," The 23rd International Review of Progress in Applied Computational Electromagnetics (ACES 2007), Verona, Italy, March 2007.
 L. Gürel, T. Malas, and Ö. Ergül, "Efficient preconditioning strategies for the multilevel fast multipole algorithm," PIERS 2007 Progress in Electromagnetics Research Symposium, Beijing, China, pp. 16201624, March 2007.
 L. Gürel, Ö. Ergül, and A. Ünal, "Accurate analysis of metamaterials involving finite arrays of splitring resonators and thin wires," PIERS 2007 Progress in Electromagnetics Research Symposium, Beijing, China, pp. 470473, March 2007.
 Ö. Ergül and L. Gürel, "Fast and accurate solutions of largescale scattering problems with parallel multilevel fast multipole algorithm," 2007 IEEE International Symposium on Antennas and Propagation, Honolulu, Hawai'i, USA, June 2007.
 Ö. Ergül and L. Gürel, "Improving the accuracy of the surface integral equations forlowcontrast dielectric scatterers," 2007 IEEE International Symposium on Antennas and Propagation, Honolulu, Hawai'i, USA, June 2007.
 Ö. Ergül and L. Gürel, "Iterative solution of the normalequations form of the electricfield integral equation," 2007 IEEE International Symposium on Antennas and Propagation, Honolulu, Hawai'i, USA, June 2007.
 Ö. Ergül, Ç. Yavuz, A. Ünal, and L. Gürel, "Investigation of various metamaterial structures using multilevel fast multipole algorithm," 2007 IEEE International Symposium on Antennas and Propagation, Honolulu, Hawai'i, USA, June 2007.
 T. Malas, Ö. Ergül, and L. Gürel, "Approximate MLFMA as an efficient preconditioner," 2007 IEEE International Symposium on Antennas and Propagation, Honolulu, Hawai'i, USA, June 2007.
 L. Gürel and A. Manyas, "Multilevel physical optics algorithm for fast solution of scattering problems involving nonuniform triangulations," 2007 IEEE International Symposium on Antennas and Propagation, Honolulu, Hawai'i, USA, June 2007.
 Ö. Ergül, A. Ünal, T. Malas, and L. Gürel, "Integralequationbased approach for the accurate analysis of metamaterials," NanoTRIII Nanoscience and Nanotechnology Conference, Ankara, Turkey, June 2007.
 L. Gürel and Ö. Ergül, "Efficient solution of the combinedfield integral equation with the parallel multilevel fast multipole algorithm," Computational Electromagnetics Workshop (CEM 07), İzmir, Turkey, August 2007.
 Alp Manyas and L. Gürel, "Memoryefficient multilevel physical optics algorithm for fast computation of scattering from threedimensional complex targets," Computational Electromagnetics Workshop (CEM 07), İzmir, Turkey, August 2007.
 Tahir Malas, Ö. Ergül, and L. Gürel, "Sequential and parallel preconditioners for largescale integralequation," Computational Electromagnetics Workshop (CEM 07), İzmir, Turkey, August 2007.
 Ö. Ergül, Alper Ünal, and Levent Gürel, "MLFMA solutions of transmission problems involving realistic metamaterial walls," Computational Electromagnetics Workshop (CEM 07), İzmir, Turkey, August 2007.
 Ö. Ergül and L. Gürel, "Fast and accurate solutions of scattering problems involving dielectric objects with moderate and low contrasts," Computational Electromagnetics Workshop (CEM 07), İzmir, Turkey, August 2007.
 Ö. Ergül, T. Malas, and L. Gürel, "Solution of extremely large integralequation problems," International Conference on Electromagnetics in Advanced Applications (ICEAA 07), Torino, Italy, Sept. 2007.
 Ö. Ergül, T. Malas, A. Ünal, and L. Gürel "Solutions of large integralequation problems with preconditioned MLFMA," 37th European Microwave Conference (EuMC), Munich, Germany, Oct. 2007.
 L. Gürel, Ö. Ergül, A. Manyas, "POMLFMA hybrid technique for the solution of electromagnetic scattering problems involving complex targets," European Conference on Antennas and Propagation (EuCAP 2007), Edinburgh, UK, Nov. 2007.
 Ö. Ergül and L. Gürel, "ParallelMLFMA solution of CFIE discretized with tens of millions of unknowns," European Conference on Antennas and Propagation (EuCAP 2007), Edinburgh, UK, Nov. 2007.
 T. Malas and L. Gürel, "Solution of large EFIE problems via preconditioned multilevel fast multipole algorithm," European Conference on Antennas and Propagation (EuCAP 2007), Edinburgh, UK, Nov. 2007.
 Ö. Ergül and L. Gürel, "Accurate solutions of scattering problems involving lowcontrast dielectric objects with surface integral equations," European Conference on Antennas and Propagation (EuCAP 2007), Edinburgh, UK, Nov. 2007.
 T. Malas, Ö. Ergül, and L. Gürel, "Effective preconditioners for large integralequation problems," European Conference on Antennas and Propagation (EuCAP 2007), Edinburgh, UK, Nov. 2007.
 Ö. Ergül, T. Malas, Ç. Yavuz, A. Ünal, and L. Gürel, "Computational analysis of complicated metamaterial structures using MLFMA and nested preconditioners," European Conference on Antennas and Propagation (EuCAP 2007), Edinburgh, UK, Nov. 2007.
 T. Malas, Ö. Ergül, and L. Gürel, "Parallel preconditioners for solutions of dense linear systems with tens of millions of unknowns," 22nd International Symposium on Computer and Information Sciences (ISCIS07), Ankara, Turkey, Nov. 2007.
 Ö. Ergül and L. Gürel, "Solution of largescale scattering problems with the multilevel fast multipole algorithm parallelized on distributedmemory architectures," 22nd International Symposium on Computer and Information Sciences (ISCIS07), Ankara, Turkey, Nov. 2007.
 W. C. Chew, C. P. Davis, K. F. Warnick, Z. P. Nie, J. Hu, S. Yan, and L. Gürel, "EFIE and MFIE, why the difference?," 2008 IEEE International Symposium on Antennas and Propagation and the 2008 USNC/URSI National Radio Science Meeting, San Diego, California, USA, July 2008.
 Ö. Ergül and L. Gürel, "Hierarchical parallelization of the multilevel fast multipole algorithm for the efficient solution of largescale scattering problems," 2008 IEEE International Symposium on Antennas and Propagation and the 2008 USNC/URSI National Radio Science Meeting, San Diego, California, USA, July 2008.
 T. Malas and L. Gürel, "Preconditioning large integralequation problems involving complex targets," 008 IEEE International Symposium on Antennas and Propagation and the 2008 USNC/URSI National Radio Science Meeting, San Diego, California, USA, July 2008.
 L. Gürel, Ö. Ergül, and T. Malas, "Solutions of extremely large electromagnetics problems involving tens of millions of unknowns using parallel MLFMA and preconditioners," XXIX General Assembly of the International Union of Radio Science, Chicago, Illinois, USA, Aug. 2008.
 Ö. Ergül and L. Gürel "Solutions of electromagnetics problems involving large dielectric objects with the multilevel fast multipole algorithm," in Turkish, URSITurkey 2008 Scientific Symposium, Antalya, Turkey, Oct. 2008.
 A. Ünal, Ö. Ergül and L. Gürel "Investigation of complicated metamaterial structures with parallel multilevel fast multipole algorithm," in Turkish, URSITurkey 2008 Scientific Symposium, Antalya, Turkey, Oct. 2008.
 S. Kılınç, Ö. Ergül and L. Gürel "Investigation of transmission properties of finite periodic dielectric structures by using integral equations and the multilevel fast multipole algorithm," in Turkish, URSITurkey 2008 Scientific Symposium, Antalya, Turkey, Oct. 2008.
 B. Tiryaki, A. Ünal, Ö. Ergül and L. Gürel "Computations and comparisons of radarcrosssection values of various airborne targets by using parallel multilevel fast multipole algorithm," in Turkish, URSITurkey 2008 Scientific Symposium, Antalya, Turkey, Oct. 2008.
 Ö. Ergül and L. Gürel "Hierarchical parallelization of MLFMA for the efficient solution of largescale electromagnetics problems," Vth International Workshop on Electromagnetic Wave Scattering (EWS), Antalya, Turkey, Oct. 2008.
 T. Malas and L. Gürel "Iterative Block NearField Preconditioners for Surface IntegralEquation Formulations of Dielectric Problems," Vth International Workshop on Electromagnetic Wave Scattering (EWS), Antalya, Turkey, Oct. 2008.
 Ö. Ergül and L. Gürel "Fieldbasedstabilized combined tangential formulation for the accurate solution of scattering problems involving lowcontrast dielectric objects," Vth International Workshop on Electromagnetic Wave Scattering (EWS), Antalya, Turkey, Oct. 2008.
 Ö. Ergül and L. Gürel "Contamination of the accuracy of the surface integral equations with the discretization error of the identity operator," Vth International Workshop on Electromagnetic Wave Scattering (EWS), Antalya, Turkey, Oct. 2008.
 P. YlaOijala, Ö. Ergül, L. Gürel, and M. Taskinen, "Efficient surface integral equation methods for the analysis of complex metamaterial structures," European Conference on Antennas and Propagation (EuCAP 2009), Berlin, Germany, March 2009.
 T. Malas and L. Gürel, "An effective preconditioner based on the Schur complement reduction for integralequation formulations of dielectric problems," 2009 IEEE International Symposium on Antennas and Propagation and 2009 USNC/URSI National Radio Science Meeting, Charleston, South Carolina, USA, June 2009.
 T. Malas and L. Gürel, "Scalable parallelization of the sparseapproximateinverse (SAI) preconditioner for the solution of largescale integralequation problems," 2009 IEEE International Symposium on Antennas and Propagation and 2009 USNC/URSI National Radio Science Meeting, Charleston, South Carolina, USA, June 2009.
 Ö. Ergül and L. Gürel, "On the errors arising in surface integral equations due to the discretization of the identity operator," 2009 IEEE International Symposium on Antennas and Propagation and 2009 USNC/URSI National Radio Science Meeting, Charleston, South Carolina, USA, June 2009.
 Ö. Ergül and L. Gürel, "Solutions of electromagnetics problems involving hundreds of millions of unknowns with parallel multilevel fast multipole algorithm," 2009 IEEE International Symposium on Antennas and Propagation and 2009 USNC/URSI National Radio Science Meeting, Charleston, South Carolina, USA, June 2009.
 Ö. Ergül and L. Gürel, "Preconditioned MLFMA solution of multiple dielectricmetallic composite objects with the electric and magnetic current combinedfield integral equation (JMCFIE)," 2009 IEEE International Symposium on Antennas and Propagation and 2009 USNC/URSI National Radio Science Meeting, Charleston, South Carolina, USA, June 2009.
 Ö. Ergül and L. Gürel, "Numerical analysis of threedimensional frequencyselective structures using the multilevel fast multipole algorithm," 23rd Biennial Conf. on Numerical Analysis, Glasgow, UK, June 2009.
 Ö. Ergül and L. Gürel, "Fast and accurate solutions of extremely large scattering problems involving threedimensional canonical and complicated objects," Computational Electromagnetics Workshop (CEM’09), Izmir, Turkey, July 2009.
 A. Manyas, Ö. Ergül, and L. Gürel, "Hybridizing physical optics with MLFMA for efficient scattering computations of threedimensional complex targets," Computational Electromagnetics Workshop (CEM’09), Izmir, Turkey, July 2009.
 Ö. Ergül, T. Malas, S. Kılınc, S. Sarıtas, and L. Gürel, "Analysis of photoniccrystal problems with MLFMA and approximate Schur preconditioners," Computational Electromagnetics Workshop (CEM’09), Izmir, Turkey, July 2009.
 T. Malas and L. Gürel, "Approximate Schur preconditioners for efficient solutions of dielectric problems formulated with surface integral equations," Computational Electromagnetics Workshop (CEM’09), Izmir, Turkey, July 2009.
 Ö. Ergül and L. Gürel, "Fast and accurate analysis of complicated metamaterial structures using a lowfrequency multilevel fast multipole algorithm," International Conference on Electromagnetics in Advanced Applications (ICEAA), Torino, Italy, Sept. 2009.
 L. Gürel and Ö. Ergül "Rigorous solutions of largescale scattering problems discretized with hundreds of millions of unknowns," International Conference on Electromagnetics in Advanced Applications (ICEAA), Torino, Italy, Sept. 2009.
 Ö. Ergül, A. ArslanErgül, and L. Gürel "Rigorous solutions of scattering problems involving red blood cells," European Conference on Antennas and Propagation (EuCAP 2010), Barcelona, Spain, April 2010.
 T. Malas and L. Gürel "Iterative solution of dielectric waveguide problems via Schur complement preconditioners," 2010 IEEE International Symposium on Antennas and Propagation and CNC/USNC/URSI Radio Science Meeting, Toronto, Ontario, Canada, July 2010.
 Ö. Ergül and L. Gürel "Advanced partitioning and communication strategies for the efficient parallelization of the multilevel fast multipole algorithm," 2010 IEEE International Symposium on Antennas and Propagation and CNC/USNC/URSI Radio Science Meeting, Toronto, Ontario, Canada, July 2010.
 L. Gürel, T. Malas, and Ö. Ergül, "Preconditioning iterative MLFMA solutions of integral equations," EMTS 2010 International Symposium on Electromagnetic Theory, Berlin, Germany, Aug. 2010.
 Ö. Ergül and L. Gürel, "An efficient parallel implementation of the multilevel fast multipole algorithm for rigorous solutions of largescale scattering problems," EMTS 2010 International Symposium on Electromagnetic Theory, Berlin, Germany, Aug. 2010.
 D. Doğan, M. E. İnal, A. Manyas, and L. Gürel, "Validation of RCS reduction with radar absorbing materials on canonical geometries," in Turkish, URSITurkey 2010 Scientific Symposium, NCTR, Aug. 2010.
 L. Gürel and Ö. Ergül, "LL basis functions: halforder increase over RWG functions significantly improves MFIE and CFIE results,"The 27th International Review of Progress in Applied Computational Electromagnetics (ACES 2011), Williamsburg, Virginia, March 2011.
 L. Gürel, "Solutions of extremely large integralequation problems involving hundreds of millions of unknowns and their applications in computational electromagnetics," Plenary Talk, The 27th International Review of Progress in Applied Computational Electromagnetics (ACES 2011), Williamsburg, Virginia, March 2011.
 Ö. Ergül and L. Gürel, "Accuracy: the frequently overlooked parameter in the solution of extremely large problems," European Conference on Antennas and Propagation (EuCAP 2011), Williamsburg, Rome, Italy, April 2011.
 L. Gürel, "Accuracy aspect of the MLFMA solutions of extremely large electromagnetics problems," 2011 International Workshop on Electromagnetic Theory, Modeling, and Simulation, Chengdu, China, June 2011.
 L. Gürel and Ö. Ergül, "Emphasizing the accuracy and efficiency aspects of solutions of extremely large benchmark problems in computational electromagnetics," Workshop on Advanced Techniques in Computational Electromagnetics (ATCEM’11), Glasgow, Scotland, UK, June 2011.
 Ö. Ergül and L. Gürel, "Extremely large electromagnetics problems: are we going in the right direction?," 24th Biennial Conference on Numerical Analysis, Glasgow, Scotland, UK, JuneJuly 2011.
 L. Gürel, "Ideas for the parallelization of (multilevel) fast multipole solvers on various dissimilar parallel computers,"" 2011 IEEE International Symposium on Antennas and Propagation and USNC/URSI National Radio Science Meeting, Spokane, Washington, USA, July 2011.
 Ö. Ergül and L. Gürel, “Analysis of lossy dielectric objects with the multilevel fast multipole algorithm,” 2011 IEEE International Symposium on Antennas and Propagation and USNC/URSI National Radio Science Meeting, Spokane, Washington, USA, July 2011.
 Ö. Ergül and L. Gürel, “Benchmark solutions of large problems for evaluating accuracy and efficiency of electromagnetics solvers,” 2011 IEEE International Symposium on Antennas and Propagation and USNC/URSI National Radio Science Meeting, Spokane, Washington, USA, July 2011.
 L. Gürel and Ö. Ergül, “Accuracy and efficiency considerations in the solution of extremely large electromagnetics problems,” Computational Electromagnetics Workshop (CEM’11), İzmir, Turkey, Aug. 2011.
 L. Gürel and Ö. Ergül, “Analysis of doublenegative materials with the surface integral equations and the multilevel fast multipole algorithm,” Computational Electromagnetics Workshop (CEM’11), İzmir, Turkey, Aug. 2011.
 Ö. Ergül and L. Gürel, “Rigorous solutions of largescale dielectric problems with the parallel multilevel fast multipole algorithm,” XXX URSI General Assembly and Scientific Symposium, Istanbul, Turkey, Aug. 2011.
 Ö. Ergül and L. Gürel, “Analysis of composite objects involving multiple dielectric and metallic partswith the parallel multilevel fast multipole algorithm,” The 28th International Review of Progress in Applied Computational Electromagnetics (ACES 2012), Columbus, Ohio, April 2012.
 Ö. Ergül and L. Gürel, “ParallelMLFMA solutions of largescale problems involving composite objects,” 2012 IEEE International Symposium on Antennas and Propagation and USNCURSI National Radio Science Meeting, Chicago, Illinois, USA, July 2012.
 L. Gürel, “Efficient parallelization of the multilevel fast multipole algorithm (MLFMA),” 2012 Indian Antenna Week (IAW), Gangtok, India, May 2012.
 L. Gürel, “Solution of extremely large integralequations in computational electromagnetics,” 2012 Indian Antenna Week (IAW), Gangtok, India, May 2012.
 L. Gürel, “Advanced numerical techniques for the scattering of waves by dielectric scatterers,” 14th International Conference on Mathematical Methods In Electromagnetic Theory Kharkiv, Ukraine, August 2012.
 L. Gürel, “Accuracy considerations for the integralequation solutions of some canonical problems,” INTELECT 2012, 6th LEMAEPFL OneDay Workshop on Integral Techniques for Electromagnetics, Sevilla, Spain, October 2012.
 L. Gürel, “Application of a parallel MLFMA to composite structures with arbitrary material properties,” The 29th International Review of Progress in Applied Computational Electromagnetics (ACES 2013), Monterey, CA, March 2013.
 Ö. Ergül and L. Gürel, “A webbased tool for benchmarking the accuracy of solutions of some canonical electromagnetics problems,” European Conference on Antennas and Propagation (EuCAP 2013), Gothenburg, Sweden, April 2013.
 L. Gürel, “A ParallelMLFMA solutions of very large benchmark problems in computational electromagnetics,” 2013 International Workshop on Electromagnetic Theory, Modelling and Simulation, University of Electronic Science and Technology of China (UESTC), Chengdu, China, June 2013.
 L. Gürel, “Recursive algorithms: early years of developing fast solvers with Prof. Chew at UIUC electromagnetics laboratory,” 2013 International Workshop on Electromagnetic Theory, Modelling and Simulation, University of Electronic Science and Technology of China (UESTC), Chengdu, China, June 2013.
 M. Hidayetoğlu, B. Karaosmanoğlu, and L. Gürel, “Reducing MLFMA memory with outofcore implementation and datastructure parallelization,” Computational Electromagnetics Workshop (CEM’13), İzmir, Turkey, Aug. 2013.
 M. Kazempour and L. Gürel, “Solution of lowfrequency electromagnetics problems using hierarchical matrices,” Computational Electromagnetics Workshop (CEM’13), İzmir, Turkey, Aug. 2013.
 A. Etminan and L. Gürel, “Microwave imaging of threedimensional conducting objects using the newton minimization approach,” Computational Electromagnetics Workshop (CEM’13), İzmir, Turkey, Aug. 2013.
 Ö. Ergül and L. Gürel, “Fast and accurate analysis of optical metamaterials using surface integral equations and the parallel multilevel fast multipole algorithm,” International Conference on Electromagnetics in Advanced Applications (ICEAA 13), Torino, Italy, Sept. 2013.
 L. Gürel, “Fast multipole methods in service of various scientific disciplines,” 2014 IEEE International Symposium on Antennas and Propagation and USNCURSI National Radio Science Meeting Memphis, TN, USA, July 2014.
 Mahdi Kazempour and L. Gürel, “Fast solution of electromagnetic scattering problems with multiple excitations using the recompressed adaptive cross approximation,” 2014 IEEE International Symposium on Antennas and Propagation and USNCURSI National Radio Science MeetingMemphis, TN, USA, July 2014.
 Aslan Etminan and L. Gürel, “Shape reconstruction of threedimensional conducting objects via nearfield measurements,”2014 IEEE International Symposium on Antennas and Propagation and USNCURSI National Radio Science Meeting Memphis, TN, USA, July 2014.
 Mert Hidayetoğlu and L. Gürel, “MLFMA memory reduction techniques for solving largescale problems,” 2014 IEEE International Symposium on Antennas and Propagation and USNCURSI National Radio Science Meeting Memphis, TN, USA, July 2014.
 Mahdi Kazempour and L. Gürel, “Algebraic acceleration and regularization of the source reconstruction method with the recompressed adaptive cross approximation,” 2014 IEEE International Symposium on Antennas and Propagation and USNCURSI National Radio Science Meeting Memphis, TN, USA, July 2014.
 Manouchehr Takrimi and L. Gürel, “A modified equivalence principle for open surfaces,”2014 IEEE International Symposium on Antennas and Propagation and USNCURSI National Radio Science Meeting Memphis, TN, USA, July 2014.
 Aslan Etminan, Alireza Sadeghi, and L. Gürel, “Electromagnetic Imaging of ThreeDimensional Dielectric Objects with Newton Minimization,” 2014 IEEE International Symposium on Antennas and Propagation and USNCURSI National Radio Science Meeting Memphis, TN, USA, July 2014.
