ABAKUS | Publications


  2015
Prof. Levent Gürel received the Harrington-Mittra Award in Computational Electromagnetics.

  2014
New book from IEEE Press and Wiley: The Multilevel Fast Multipole Algorithm (MLFMA) for Solving Large-Scale Computational Electromagnetics Problems.

  2014
Another achievement in the series of world record: More than one billion unknown solved.

  2013
Prof. Levent Gürel received 2013 UIUC ECE Distinguished Alumni Award.

  2011
Prof. Gürel is elevated to ACES Fellow Grade.

  2011
Prof. Gürel is invited to address the 2011 ACES Conference in Virginia, USA, as a Plenary Speaker.

  2011
Prof. Levent Gürel is named IEEE Distinguished Lecturer.

   2009
Prof. Levent Gürel is elevated to IEEE Fellow grade


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Publications


    Journal Papers

  1. 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. MTT-36, pp. 1488-1497, Nov. 1988. 

  2. 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. MTT-36, pp. 1498-1506, Nov. 1988. 

  3. L. Gürel and W. C. Chew, “Recursive algorithms for calculating the scattering from N strips or patches,” IEEE Trans. Antennas Propagat.vol. AP-38, pp. 507-515, Apr. 1990. 

  4. L. Gürel and W. C. Chew, “A recursive T-matrix algorithm for strips and patches,” Radio Science, vol. 27,pp. 387-401, May-June 1992. 

  5. W. C. Chew, L. Gürel, Y. M. Wang, G. Otto, R. Wagner, and Q. H. Liu, “A generalized recursive algorithm for wave-scattering solutions in two dimensions,” IEEE Trans. Microwave Theory Tech., vol. MTT-40, pp. 716-723, April 1992. 

  6. 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. 1537-1560, Nov. 1992. 

  7. L. Gürel and W. C. Chew, “Scattering solution of three-dimensional array of patches using the recursive T-matrix algorithms,” IEEE Microwave and Guided Wave Lett., vol. 2, pp. 182-184, May 1992. 

  8. L. Gürel and W. C. Chew, “Recursive T-matrix algorithms for the solution of electromagnetic scattering from strip and patch geometries,” IEEE Trans. Antennas Propagat.,vol. AP-41, pp. 91-99, Jan. 1993. 

  9. 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. 277-279, Aug. 1996.  

  10. 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. 2189-2199, Nov.-Dec. 1997.  

  11. 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. 155-157, April 1998. 

  12. U. Oğuz, L. Gürel and O. Arıkan, “An efficient and accurate technique for the incident-wave excitations in the FDTD method,” IEEE Trans. Microwave Theory Tech., vol. 46, no. 6, pp. 869-882, June 1998. 

  13. 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. 1373-1387, Nov.-Dec. 1999. 

  14. L. Gürel and U. Oğuz, “Signal-processing techniques to reduce the sinusoidal steady-state error in the FDTD method,” IEEE Trans. Antennas Propagat. vol. 48, no. 4, pp. 585-593, April 2000.  

  15. L. Gürel and U. Oğuz, “Three-dimensional FDTD modeling of a ground-penetrating radar,” IEEE Trans. Geosci. Remote Sensing, vol. 38, no. 4, pp. 1513-1521, July 2000.

  16. L. Gürel and U. Oğuz, “Simulations of ground-penetrating radars over lossy and heterogeneous grounds,” IEEE Trans. Geosci. Remote Sensing, vol. 39, no. 6, pp. 1190-1197, June 2001.

  17. U. Oğuz and L. Gürel, “Modeling of ground-penetrating-radar antennas with shields and simulated absorbers,” IEEE Trans. Antennas Propagat, vol. 49, no. 11, pp. 1560-1567, Nov. 2001.

  18. M. I. Aksun, F. Caliskan, and L. Gürel, “An efficient method for electromagnetic characterization of 2-D geometries in stratified media,” IEEE Trans. Microwave Theory Tech., vol. 50, no. 5, pp. 1264-1274, May 2002.

  19. L. Gürel and U. Oğuz, “Transmitter-receiver-transmitter configurations of the ground-penetrating radar,” Radio Science, vol. 37, no.3, pp. 5-1 - 5-7, May 2002.

  20. U. Oğuz and L. Gürel, "Application of signal-processing techniques to dipole excitations in the finite-difference time-domain method," J. Electromagn. Waves Appl.vol. 16, no. 5, pp. 671-687, May 2002.

  21. U. Oğuz and L. Gürel, "Frequency responses of ground-penetrating radars operating over highly lossy grounds," IEEE Trans. Geosci. Remote Sensingvol. 40, no. 6, pp. 1385-1394, June 2002.

  22. L. Gürel and U. Oğuz, "Transmitter-receiver-transmitter-configured ground-penetrating radars over randomly heterogeneous ground models," Radio Science, vol. 37, no. 6, pp. 6-1 - 6-9, Nov.-Dec. 2002.

  23. U. Oğuz and L. Gürel, "Optimization of the transmitter-receiver separation in the ground-penetrating radar," IEEE Trans. Antennas Propagat., vol. 51, no. 3, pp. 362-370, Mar. 2003.

  24. 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. 12-1 - 12-10, June 2003.

  25. U. Oğuz and L. Gürel, "Reducing the dispersion errors of the finite-difference time-domain method for multifrequency plane-wave excitations," Electromagnetics, vol. 23, no. 6, pp. 539 - 552, Aug.-Sep. 2003.

  26. Ö. Ergül and L. Gürel, "Nonplanar trapezoidal-tooth log-periodic antennas: design and electromagnetic modelling," Radio Science, vol. 40, RS5010, doi:10.1029/2004RS003215, Oct. 2005.

  27. Ö. Ergül and L. Gürel, "Solid-angle factor in the magnetic-field integral equation," Microwave and Opt. Technol. Lett., vol. 45, no. 5, pp. 452-456, June 2005.

  28. L. Gürel and Ö. Ergül, "Singularity of the magnetic-field integral equation and its extraction," IEEE Antennas Wireless Propagat. Lett., vol. 4, pp. 229-232, 2005.

  29. Ö. Ergül and L. Gürel, "Improved testing of the magnetic-field integral equation," IEEE Microwave Wireless Comp. Lett., vol. 15, no. 10, pp. 615-617, Oct. 2005.

  30. Ö. Ergül and L. Gürel, "The use of curl-conforming basis functions for the magnetic-field integral equation," IEEE Trans. Antennas Propagat., vol. 54, no. 7, pp. 1917-1926, July 2006.

  31. Ö. Ergül and L. Gürel, "Improving the accuracy of the magnetic-field integral equation with the linear-linear basis functions," Radio Sci., vol. 41, RS4004, doi:10.1029/2005RS003307, July 2006.

  32. Ö. Ergül and L. Gürel, "Enhancing the accuracy of the interpolations and anterpolations in MLFMA," IEEE Antennas Wireless Propagat. Lett., vol. 5, pp. 467-470, 2006.

  33. Ö. Ergül and L. Gürel, "Optimal interpolation of translation operator in multilevel fast multipole algorithm," IEEE Trans. Antennas Propagat., vol. 54, no. 12, pp. 3822-3826, Dec. 2006.

  34. L. Gürel and Ö. Ergül, "Extending the applicability of the combined-field integral equation to geometries containing open surfaces," IEEE Antennas Wireless Propagat. Lett., vol. 5, pp. 515-516, 2006.

  35. Ö. Ergül and L. Gürel, "Linear-linear basis functions for MLFMA solutions of magnetic-field and combined-field integral equations," IEEE Trans. Antennas Propagat., vol. 55, no. 4, pp. 1103-1110, Apr. 2007.

  36. 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. 1476-1494, June 2007.

  37. Ö. Ergül and L. Gürel, "Modeling and synthesis of circular-sectoral arrays of log-periodic antennas using multilevel fast multipole algorithm and genetic algorithms," Radio Science, vol. 42, RS3018, doi:10.1029/2006RS003567, June 2007.

  38. L. Gürel and Ö. Ergül, "Fast and accurate solutions of extremely large integral-equation problems discretized with tens of millions of unknowns," Electron. Lett., vol. 43, no. 9, pp. 499-500, doi:10.1049/el:20070639, Apr. 2007.

  39. Ö. Ergül and L. Gürel, "Efficient solution of the electric-field integral equation by the iterative LSQR algorithm," IEEE Antennas Wireless Propagat. Lett., vol. 7, pp. 36-39, 2008.

  40. Ö. Ergül and L. Gürel, "Hierarchical parallelisation strategy for the multilevel fast multipole algorithm in computational electromagnetics," Electron. Lett., vol. 44, no. 1, pp. 3-5, Mar2008.

  41. Ö. Ergül and L. Gürel, "Stabilization of integral-equation formulations for the accurate solution of scattering problems involving low-contrast dielectric objects," IEEE Trans. Antennas Propagat., vol. 56, pp. 799-805, 2008.

  42. Ö. Ergül and L. Gürel, "Efficient parallelization of the multilevel fast multipole algorithm for the solution of large-scale scattering problems," IEEE Trans. Antennas Propagat., vol. 56, no. 8, pp. 2335-2345, Aug. 2008.

  43. 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. 9898-9912, Dec. 2008.

  44. L. Gürel and Ö. Ergül, "Design and simulation of circular arrays of trapezoidal-tooth log-periodic antennas via genetic optimization," Prog. Electromagn. Res., PIER 85, pp. 243-260, 2008.

  45. Ö. Ergül and L. Gürel, "Comparison of integral-equation 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. 176-187, Jan. 2009. 

  46. T. Malas and L. Gürel, "Accelerating the multilevel fast multipole algorithm with the sparse-approximate-inverse (SAI) preconditioning," SIAM J. Sci. Comput., vol. 31, no.3, pp. 1968-1984, March 2009. 

  47. Ö. Ergül, I. van den Bosch, and L. Gürel, "Two-step Lagrange interpolation method for the multilevel fast multipole algorithm," IEEE Antennas Wireless Propagat. Lett., vol. 8, pp. 69-71, 2009. 

  48. 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. 

  49. 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. 

  50. 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 179-198, 2009. 

  51. L. Gürel and Ö. Ergül, "Contamination of the accuracy of the combined-field integral equation with the discretization error of the magnetic-field integral equation," IEEE Trans. Antennas Propagat., vol. 57, no. 9, pp. 2650–2657, Sept. 2009. 

  52. Ö. Ergül and L. Gürel, "Discretization error due to the identity operator in surface integral equations," Comput. Phys. Commun., vol. 180, no. 10, pp. 1746-1752, Oct 2009. 

  53. Ö. Ergül and L. Gürel, "Efficient solution of the electric and magnetic current combined-field integral equation with the multilevel fast multipole algorithm and block-diagonal preconditioning," Radio Science, vol. 44, RS6001, doi:10.1029/2009RS004143. 

  54. L. Gürel and T. Malas, "Iterative near-field preconditioner for the multilevel fast multipole algorithm," SIAM J. Sci. Comput., vol. 32, no. 4, pp. 1929–1949, 2010. 

  55. Ö. Ergül, A. Arslan-Ergül 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. 

  56. Ö. Ergül, T. Malas and L. Gürel, "Solutions of large-scale electromagnetics problems using an iterative inner-outer scheme with ordinary and approximate multilevel fast multipole algorithms," Prog. Electromagn. Res., PIER 85, vol. 106, pp. 203-223, 2010. 

  57. Ö. Ergül and L. Gürel, "Efficient solutions of metamaterial problems using a low-frequency multilevel fast multipole algorithm," Prog. Electromagn. Res., vol. 108, no. 81-99, 2010. 

  58. Ö. Ergül and L. Gürel, "Improving iterative solutions of the electric-field integral equation via transformations into normal equations," J. of Electromagn. Waves and Appl., vol. 24, no. 16, pp. 2129–2138, Nov. 2010. 

  59. 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. 18-27, Feb. 2011. 

  60. Ö. Ergül, T. Malas, and L. Gürel, "Analysis of dielectric photonic-crystal problems with MLFMA and Schur-complement preconditioners," J. Lightw. Technol., vol. 29, no. 6, pp. 888-897, Mar. 2011. 

  61. T. Malas and L. Gürel, "Schur complement preconditioners for surface integral-equation formulations of dielectric problems solved with the multilevel fast multipole algorithm," SIAM J. Sci. Comput., vol. 33, no. 5, pp. 2440–2467, 2011. 

  62. Ö. Ergül and L. Gürel, "Rigorous analysis of double-negative materials with the multilevel fast multipole algorithm," Applied Computational Electromagnetics Society (ACES) Journal, vol. 27, no. 2, pp. 161-168, Feb. 2012. 

  63. 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. 

  64. Ö. Ergül and L. Gürel, "Accurate solutions of extremely large integral-equation problems in computational electromagnetics," IEEE Proceedings, , vol. 101, no. 2, pp. 342 - 349, Feb. 2013. 

  65. Ö. Ergül and L. Gürel, "Fast and Accurate Analysis of Large-Scale Composite Structures with the Parallel Multilevel Fast Multipole Algorithm," J. Opt. Soc. Am. A, vol. 30, no. 3, pp. 509 - 517, March 2013. 


  66. Conference Papers

  1. 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.

  2. 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.

  3. 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.

  4. 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.

  5. 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. 278-291, Mar. 1991.

  6. L. Gürel and W. C. Chew, "On the connection of T matrices and integral equations," 1991 International IEEE AP-S Symposium Digest, London, Ontario, Canada, June 1991.

  7. L. Gürel and W. C. Chew, "Recursive T-matrix algorithms for 1-D and 2-D clusterings of strips," 1991 International IEEE AP-S Symposium Digest, London, Ontario, Canada, June 1991.

  8. L. Gürel and W. C. Chew, "Recursive T-matrix algorithms for conducting patches," 1991 North American Radio Science Meeting, Program and Abstracts, London, Ontario, Canada, June 1991.

  9. 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.

  10. W. C. Chew, Y. M. Wang, and L. Gürel, "A recursive algorithm using windowed addition theorem," 1992 IEEE AP-S International Symposium Digest, Chicago, IL, pp. 1587-1590, July 1992.

  11. L. Gürel, "Fast algorithm for electromagnetic solution of modified-geometry problems," 1993 IEEE AP-S International Symposium Digest, Ann Arbor, MI, pp. 60-63, June 1993.

  12. L. Gürel and T. Gürel, "Absorbing boundary condition for monochromatic oblique incidence," Progress in Electromagnetics Research Symposium Proceedings, Pasadena, CA, p. 118, July 1993.

  13. 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.

  14. L. Gürel, "Fast-multipole-method solution of two-dimensional conductor geometries," 1995 IEEE AP-S International Symposium and URSI Radio Science Meeting, Newport Beach, CA, June 1995.

  15. L. Gürel, "Computational electromagnetics, electromagnetic compatibility and European Community," in Turkish, 6. National Symposium of Electrical Engineering, Bursa, Turkey, Sept. 1995.

  16. L. Gürel and M. I. Aksun, "Fast multipole method in layered media: 2-D electromagnetic scattering problems," 1996 IEEE AP-S International Symposium and URSI Radio Science Meeting, Baltimore, MD, July 1996.

  17. 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.

  18. L. Gürel, "Electromagnetic compatibility and computational electromagnetics," in Turkish, Symposium for the Technological Progress in the Defense Industry, Ankara, Turkey, June 1997.

  19. 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.

  20. 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.

  21. İ. K. Şendur and L. Gürel, "FMM solution of large three-dimensional electromagnetics problems with arbitrary surface triangulations," Progress in Electromagnetics Research Symposium, Cambridge, MA, July 1997.

  22. K. Sertel and L. Gürel, "FMM solution of electromagnetic scattering problems involving curved surfaces," Progress in Electromagnetics Research Symposium, Cambridge, MA, July 1997.

  23. L. Gürel, U. Oğuz, and O. Arıkan, "Accurate plane-wave excitation in the FDTD method," 1997 IEEE AP-S International Symposium and URSI Radio Science Meeting, Montreal, Canada, July 1997.

  24. U. Oğuz and L. Gürel, "Subsurface-scattering calculations via the 3D FDTD method employing PML ABC for layered media," 1997 IEEE AP-S International Symposium and URSI Radio Science Meeting, Montreal, Canada, July 1997.

  25. L. Gürel and W. C. Chew, "Fast direct solution algorithm for electromagnetic scattering from 3D planar and quasi-planar geometries," 1997 IEEE AP-S International Symposium and URSI Radio Science Meeting, Montreal, Canada, July 1997.

  26. L. Gürel, İ. K. Şendur, and K. Sertel, "Quantitative comparison of rooftop and RWG basis functions," 1997 IEEE AP-S International Symposium and URSI Radio Science Meeting, Montreal, Canada, July 1997.

  27. K. Sertel and L. Gürel, "A comparison of surface-modeling techniques," 1997 IEEE AP-S International Symposium and URSI Radio Science Meeting, Montreal, Canada, July 1997.

  28. İ. K. Şendur and L. Gürel, "Solution of radiation problems using the fast multipole method," 1997 IEEE AP-S International Symposium and URSI Radio Science Meeting, Montreal, Canada, July 1997.

  29. L. Gürel and W. C. Chew, "Fast direct (noniterative) solvers for integral-equation formulations of scattering problems," 1998 IEEE AP-S International Symposium and URSI North American Radio Science Meeting, Atlanta, GA, June 1998.

  30. L. Gürel and W. C. Chew, "Fast noniterative steepest descent path algorithm for planar and quasi-planar patch geometries," 1998 IEEE AP-S International Symposium and URSI North American Radio Science Meeting, Atlanta, GA, June 1998.

  31. F. Çalışkan, M. I. Aksun, and L. Gürel, "Efficient methods for electromagnetic characterization of 2-D geometries in stratified media," 1998 IEEE AP-S International Symposium and URSI North American Radio Science Meeting, Atlanta, GA, June 1998.

  32. L. Gürel, Kubilay Sertel, and İbrahim Kürş at Şendur, "On the charge-modeling capabilities of a class of current basis functions," Progress in Electromagnetics Research Symposium, Nantes, France, July 1998.

  33. 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.

  34. L. Gürel, A. E. Yılmaz, and W. C. Chew, "Fast computation of scattering from (near-)resonant structures," Proceedings of the 1999 IEEE AP-S International Symposium and USNC/URSI National Radio Science Meeting, pp. 1174-1177, Orlando, Florida, USA, July 1999.

  35. L. Gürel and U. Oğuz, "Employing PML absorbers in the design and simulation of ground penetrating radars," Proceedings of the 1999 IEEE AP-S International Symposium and USNC/URSI National Radio Science Meeting, pp. 1890-1893, Orlando, Florida, USA, July 1999.

  36. L. Gürel, "Electromagnetic compatibility standards and computer simulations," in Turkish, Proceedings of the 1999 Symposium of Effects of Electromagnetic Pollution, pp. 61-64, Ankara, Turkey, Nov. 1999.

  37. L. Gürel and U. Oğuz, "Simulation of realistic three-dimensional GPR scenarios using the FDTD method," Progress in Electromagnetics Research Symposium, Cambridge, Massachusetts, USA, July 2000.

  38. U. Oğuz and L. Gürel, "Three-dimensional FDTD modeling of a GPR," Proceedings of the 2000 IEEE AP-S International Symposium and USNC/URSI National Radio Science Meeting, Salt Lake City, Utah, USA, July 2000.

  39. 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.

  40. U. Oğuz and L. Gürel, "Electromagnetic modeling of mine detection systems," in Turkish, National Defense Industry Symposium, Ankara , Turkey, Nov. 2000.

  41. L. Gürel, "Electromagnetic compatibility (EMC) in defense systems and EMC education," in Turkish, National Defense Industry Symposium, Ankara, Turkey, Nov. 2000.

  42. L. Gürel and Ö. Ergül, "Design of broadband log-periodic antenna arrays using genetic algorithms," in Turkish, Space Symposium: Global Space Activities and Potential in Turkey, Ankara, Turkey, pp. 411-416, May 2001.

  43. 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. 443-449, May 2001.

  44. 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. 403-410, May 2001.

  45. 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. 395-402, May 2001.

  46. U. Oğuz and L. Gürel, "On the frequency-band selection for ground-penetrating radars operating over lossy and heterogeneous grounds," 2001 IEEE AP-S International Symposium and USNC/URSI National Radio Science Meeting, Boston, Massachusetts, USA, July 2001.

  47. U. Oğuz and L. Gürel, "Simulation of TRT-configured ground-penetrating radars over heterogeneous grounds," 2001 IEEE AP-S International Symposium and USNC/URSI National Radio Science Meeting, Boston, Massachusetts, USA, July 2001.

  48. L. Gürel and U. Oğuz, "Application of signal-processing techniques to reduce the errors related to the FDTD excitations," 2001 IEEE AP-S International Symposium and USNC/URSI National Radio Science Meeting, Boston, Massachusetts, USA, July 2001.

  49. L. Gürel and H. Bağcı, "FMM computation of the bistatic RCS of stealth and nonstealth targets," 2002 IEEE AP-S International Symposium and URSI National Radio Science Meeting, San Antonio, Texas, USA, June 2002.

  50. Ö. Ergül and L. Gürel "Electric-field, magnetic-field, and combined-field integral equations for electromagnetic scattering problems," in Turkish, URSI-Turkey-2002 Scientific Conference and National General Assembly Meeting, İstanbul Technical University, İstanbul, Turkey, pp. 158-161, Sept. 2002.

  51. Ö. Ergül and L. Gürel, "Broadband log-periodic antenna-array design using genetic algorithms in an electromagnetic simulation environment," in Turkish, URSI-Turkey-2002 Scientific Conference and National General Assembly Meeting, İstanbul Technical University, İstanbul, Turkey,pp. 154-157, Sept. 2002.

  52. L. Gürel, "Electromagnetic compatibility simulations," in Turkish, URSI-Turkey-2002 Scientific Conference and National General Assembly Meeting, İstanbul Technical University, İstanbul, Turkey, Sept. 2002.

  53. L. Gürel and U. Oğuz, "Electromagnetic simulations of ground-penetrating radars," in Turkish, URSI-Turkey-2002 Scientific Conference and National General Assembly Meeting, İstanbul Technical University, İstanbul, Turkey, Sept. 2002.

  54. C. Cengiz Yıldırım and L. Gürel, "Electromagnetic method of moments in the presence of an infinitely large conducting plane," in Turkish, URSI-Turkey-2002 Scientific Conference and National General Assembly Meeting, İstanbul Technical University, İstanbul, Turkey, Sept. 2002.

  55. 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.

  56. L. Gürel, "Domestic R&D contributions for national defense projects," in Turkish, Symposium on Strategic Relations in the Defense Industry, Ankara, Turkey, Nov. 2002.

  57. 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.

  58. L. Gürel, "Electromagnetic modelling and simulation," in Turkish, Symposium: Modelling and Simulation for Defense Applications, Ankara, Turkey, May 2003.

  59. U. Oğuz and L. Gürel, "FDTD simulations of multiple GPR systems," 2003 IEEE AP-S International Symposium and USNC/CNC/URSI National Radio Science Meeting, Columbus, Ohio, June 2003.

  60. Ö. Ergül and L. Gürel, "Log-periodic antenna design using electromagnetic simulations," 2003 IEEE AP-S International Symposium and USNC/CNC/URSI National Radio Science Meeting, Columbus, Ohio, vol. 1, pp. 245-248, June 2003.

  61. Ö. Ergül and L. Gürel, "Comparisons of FMM implementations employing different formulations and iterative solvers," 2003 IEEE AP-S International Symposium and USNC/CNC/URSI National Radio Science Meeting, Columbus, Ohio, vol. 1, pp. 19-22, June 2003.

  62. L. Gürel and U. Oğuz, "Three-dimensional electromagnetic modeling of various GPR problems," PIERS 2003 Progress in Electromagnetics Research Symposium, Honolulu, Hawaii, USA, Oct. 2003.

  63. 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.

  64. L. Gürel, "3-D FDTD simulations of ground penetrating radar scenarios," PIERS 2004 Progress in Electromagnetics Research Symposium, Pisa , Italy , Mar. 2004.

  65. Ö. Ergül and L. Gürel, "Investigation of the inaccuracy of the MFIE discretized with the RWG basis functions," 2004 IEEE AP-S International Symposium and URSI Radio Science Meeting, Monterey, CA, vol. 3, pp. 3393-3396, June 2004.

  66. Ö. Ergül and L. Gürel, "Improving of the accuracy of the MFIE with the choice of basis functions," 2004 IEEE AP-S International Symposium and URSI Radio Science Meeting, Monterey, CA, vol. 3, pp. 3389-3392, June 2004.

  67. Ö. Ergül and L. Gürel, "Problems in the use of the RWG functions for the magnetic-field integral equation," in Turkish, URSI-Turkey 2004 Scientific Symposium, Ankara, Turkey, pp. 74-76, Sept. 2004.

  68. Ö. Ergül and L. Gürel, "The use of linear basis functions for the magnetic-field integral equation," in Turkish, URSI-Turkey 2004 Scientific Symposium, Ankara , Turkey , pp. 90-92, Sept. 2004.

  69. Ö. Ergül, A. R. Bozbulut, and L. Gürel, "Parallelization of the multi-level fast multipole method for the solution of large electromagnetic scattering problems," in Turkish, URSI-Turkey 2004 Scientific Symposium, Ankara, Turkey, pp. 71-73, Sept. 2004.

  70. F. Yıldırım and L. Gürel, "Extrapolation of frequency domain solution of electromagnetic problems with matrix pencil method," in Turkish, URSI-Turkey 2004 Scientific Symposium, Ankara, Turkey, Sept. 2004.

  71. 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.

  72. Ö. Ergül and L. Gürel, "Combined-field 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. 325-328, April 2005.

  73. F. Yıldırım and L. Gürel, "Coupled matrix pencil method for frequency extrapolation of electromagnetic solutions," 2005 IEEE AP-S International Symposium and USNC/URSI National Radio Science Meeting, Washington , DC , USA , July 2005.

  74. L. Gürel and F. Yıldırım, "Coupled deconvolution for frequency extrapolation of electromagnetic solutions with matrix pencil method," 2005 IEEE AP-S International Symposium and USNC/URSI National Radio Science Meeting, Washington , DC , USA , July 2005.

  75. L. Gürel and Ö. Ergül, "Solution of large CEM problems with parallel multi-level fast multipole algorithm (MLFMA)," 2005 IEEE AP-S International Symposium and USNC/URSI National Radio Science Meeting, Washington , DC , USA , July 2005.

  76. Ö. Ergül and L. Gürel, "Iterative least-squares solution of the combined-field integral equation," 2005 IEEE AP-S International Symposium and USNC/URSI National Radio Science Meeting, Washington , DC , USA , July 2005.

  77. Ö. Ergül and L. Gürel, "Hybrid CFIE-EFIE solution of composite geometries with coexisting open and closed surfaces," 2005 IEEE AP-S International Symposium and USNC/URSI National Radio Science Meeting, Washington, DC, USA, vol. 4B,. pp. 289-292, July 2005.

  78. L. Gürel, Ö. Ergül, and T. Malas, "Preconditioned iterative solution of the combined-field integral equation with the MLFMA," PIERS 2005 Progress in Electromagnetics Research Symposium, Hangzhou, China, Aug. 2005.

  79. Ö. Ergül and L. Gürel, "On the lagrange interpolation in multilevel fast multipole algorithm," 2006 IEEE AP-S International Symposium and USNC/URSI National Radio Science Meeting and AMEREM Meeting, Albuquerque, New Mexico, USA, pp. 1891-1894, July 2006.

  80. L. Gürel and Ö. Ergül, "Investigations of load balancing, communications, and scalability in parallel MLFMA," 2006 IEEE AP-S International Symposium and USNC/URSI National Radio Science Meeting and AMEREM Meeting, Albuquerque, New Mexico, USA, July 2006.

  81. Ö. Ergül and L. Gürel, "Design of circular log-periodic arrays using electromagnetic simulations," 2006 IEEE AP-S International Symposium and USNC/URSI National Radio Science Meeting and AMEREM Meeting, Albuquerque, New Mexico, USA, pp. 4023-4026, July 2006.

  82. L. Gürel and T. Malas, "Variable preconditioning with nested iterations employing MLFMA," 2006 IEEE AP-S International Symposium and USNC/URSI National Radio Science Meeting and AMEREM Meeting, Albuquerque, New Mexico, USA, July 2006.

  83. T. Malas and L. Gürel, "Incomplete LU preconditioning strategies for MLFMA," 2006 IEEE AP-S International Symposium and USNC/URSI National Radio Science Meeting and AMEREM Meeting, Albuquerque, New Mexico, USA, July 2006.

  84. L. Gürel, Ö. Ergül, and A. Ünal, "MLFMA modeling of metamaterials containing split-ring resonators," 2006 IEEE AP-S International Symposium and USNC/URSI National Radio Science Meeting and AMEREM Meeting, Albuquerque, New Mexico, USA, July 2006.

  85. 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.

  86. L. Gürel and Ö. Ergül, "Iterative solution of composite problems with the combined-field integral equation," 36th European Microwave Conference 2006, Manchester, UK, pp. 239-240, Sept. 2006.

  87. L. Gürel, A. Ünal, and Ö. Ergül, "Electromagnetic modeling of split-ring resonators," 36th European Microwave Conference 2006, Manchester, UK, pp. 303-305, Sept. 2006.

  88. Ö. Ergül and L. Gürel, "Efficient solutions of circular arrays of log-periodic antennas via the electric-field integral equation," in Turkish, URSI-Turkey 2006 Scientific Symposium, Ankara, Turkey, pp. 76-78, Sept. 2006.

  89. Ö. Ergül and L. Gürel, "Least-squares solution of the electric-field integral equation," in Turkish, URSI-Turkey 2006 Scientific Symposium, Ankara, Turkey, pp. 52-54. Sept. 2006.

  90. Ö. Ergül and L. Gürel, "Investigation of integral-equation formulations for iterative solutions of dielectric bodies," in Turkish, URSI-Turkey 2006 Scientific Symposium, Ankara, Turkey, pp. 46-48. Sept. 2006.

  91. Ö. Ergül and L. Gürel, "Solution of composite geometries with open and closed surfaces via the hybrid-field integral equation," in Turkish, URSI-Turkey 2006 Scientific Symposium, Ankara, Turkey, pp. 22-24, Sept. 2006.

  92. Ö. Ergül, A. Ünal, and L. Gürel, "Electromagnetic simulation of large metamaterial structures," in Turkish, URSI-Turkey 2006 Scientific Symposium, Ankara, Turkey, pp. 376-378, Sept. 2006.

  93. Ö. Ergül and L. Gürel, "Parallelization of the multilevel fast multipole algorithm for the solution of three-dimensional arbitrary geometries," in Turkish, URSI-Turkey 2006 Scientific Symposium, Ankara, Turkey, pp. 40-42, Sept. 2006.

  94. A. Manyas and L. Gürel, "Solution of high-frequency scattering problems of complex geometries via multilevel PO algorithm," in Turkish, URSI-Turkey 2006 Scientific Symposium, Ankara, Turkey, Sept. 2006.

  95. T. Malas and L. Gürel, "Using nested solvers as effective preconditioners in computational electromagnetics," in Turkish, URSI-Turkey 2006 Scientific Symposium, Ankara, Turkey, Sept. 2006.

  96. T. Malas and L. Gürel, "Incomplete LU preconditioners for surface integral equations," in Turkish, URSI-Turkey 2006 Scientific Symposium, Ankara, Turkey, Sept. 2006.

  97. T. Malas and L.Gürel, "A parallel sparse approximate inverse preconditioner for the multilevel fast multipole algorithm," in Turkish, URSI-Turkey 2006 Scientific Symposium, Ankara, Turkey, Sept. 2006.

  98. L. Gürel, Ö. Ergül, and T. Malas, "Parallel MLFMA solution of large integral-equation problems," in Turkish, URSI-Turkey 2006 Scientific Symposium, Ankara, Turkey, pp. 31-33, Sept. 2006.

  99. Ö. Ergül, F. Akdeniz, and L. Gürel, "Efficient and accurate electromagnetic simulation of double-ridged horn antennas with the multilevel fast multipole algorithm, in Turkish, URSI-Turkey 2006 Scientific Symposium, Ankara, Turkey, pp. 170-172, Sept. 2006.

  100. 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. 8.15-8.20, Sept. 2006.

  101. Ö. Ergül and L. Gürel, "Rigorous analysis of circular log-periodic arrays using the multilevel fast multipole algorithm," IV. International Workshop on Electromagnetic Wave Scattering, Gebze,Turkey, pp. 6.15-6.20, Sept. 2006.

  102. T. Malas and L. Gürel, "Effective preconditioning techniques for iterative solutions of integral-equation methods," IV. International Workshop on Electromagnetic Wave Scattering, Gebze, Turkey, Sept. 2006.

  103. 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. 10.9-10.17, Sept. 2006.

  104. 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.

  105. Ö. Ergül and L. Gürel, "Circular arrays of log-periodic antennas for broadband applications, "European Conference on Antennas and Propagation (EuCAP 2006), Nice, France, Nov. 2006.

  106. Ö. Ergül and L. Gürel, "Efficient parallelization of multilevel fast multipole algorithm," European Conference on Antennas and Propagation (EuCAP 2006), Nice, France, Nov. 2006.

  107. 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.

  108. T. Malas and L. Gürel, "Incomplete LU preconditioning for the electric-field integral equation," European Conference on Antennas and Propagation (EuCAP 2006), Nice, France, Nov. 2006.

  109. A. Manyas and L. Gürel, "Multilevel PO algorithm for non-uniform triangulations," European Conference on Antennas and Propagation (EuCAP 2006), Nice, France, Nov. 2006.

  110. 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.

  111. 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.

  112. L. Gürel, Ö. Ergül, and T. Malas, "Solutions of large integral-equation problems with parallel preconditioned MLFMA," The 23rd International Review of Progress in Applied Computational Electromagnetics (ACES 2007), Verona, Italy, March 2007.

  113. 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. 1620-1624, March 2007.

  114. L. Gürel, Ö. Ergül, and A. Ünal, "Accurate analysis of metamaterials involving finite arrays of split-ring resonators and thin wires," PIERS 2007 Progress in Electromagnetics Research Symposium, Beijing, China, pp. 470-473, March 2007.

  115. Ö. Ergül and L. Gürel, "Fast and accurate solutions of large-scale scattering problems with parallel multilevel fast multipole algorithm," 2007 IEEE International Symposium on Antennas and Propagation, Honolulu, Hawai'i, USA, June 2007.

  116. Ö. Ergül and L. Gürel, "Improving the accuracy of the surface integral equations forlow-contrast dielectric scatterers," 2007 IEEE International Symposium on Antennas and Propagation, Honolulu, Hawai'i, USA, June 2007.

  117. Ö. Ergül and L. Gürel, "Iterative solution of the normal-equations form of the electric-field integral equation," 2007 IEEE International Symposium on Antennas and Propagation, Honolulu, Hawai'i, USA, June 2007.

  118. 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.

  119. 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.

  120. 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.

  121. Ö. Ergül, A. Ünal, T. Malas, and L. Gürel, "Integral-equation-based approach for the accurate analysis of metamaterials," NanoTR-III Nanoscience and Nanotechnology Conference, Ankara, Turkey, June 2007.

  122. L. Gürel and Ö. Ergül, "Efficient solution of the combined-field integral equation with the parallel multilevel fast multipole algorithm," Computational Electromagnetics Workshop (CEM 07), İzmir, Turkey, August 2007.

  123. Alp Manyas and L. Gürel, "Memory-efficient multilevel physical optics algorithm for fast computation of scattering from three-dimensional complex targets," Computational Electromagnetics Workshop (CEM 07), İzmir, Turkey, August 2007.

  124. Tahir Malas, Ö. Ergül, and L. Gürel, "Sequential and parallel preconditioners for large-scale integral-equation," Computational Electromagnetics Workshop (CEM 07), İzmir, Turkey, August 2007.

  125. 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.

  126. 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.

  127. Ö. Ergül, T. Malas, and L. Gürel, "Solution of extremely large integral-equation problems," International Conference on Electromagnetics in Advanced Applications (ICEAA 07), Torino, Italy, Sept. 2007.

  128. Ö. Ergül, T. Malas, A. Ünal, and L. Gürel "Solutions of large integral-equation problems with preconditioned MLFMA," 37th European Microwave Conference (EuMC), Munich, Germany, Oct. 2007.

  129. L. Gürel, Ö. Ergül, A. Manyas, "PO-MLFMA hybrid technique for the solution of electromagnetic scattering problems involving complex targets," European Conference on Antennas and Propagation (EuCAP 2007), Edinburgh, UK, Nov. 2007.

  130. Ö. Ergül and L. Gürel, "Parallel-MLFMA solution of CFIE discretized with tens of millions of unknowns," European Conference on Antennas and Propagation (EuCAP 2007), Edinburgh, UK, Nov. 2007.

  131. 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.

  132. Ö. Ergül and L. Gürel, "Accurate solutions of scattering problems involving low-contrast dielectric objects with surface integral equations," European Conference on Antennas and Propagation (EuCAP 2007), Edinburgh, UK, Nov. 2007.

  133. T. Malas, Ö. Ergül, and L. Gürel, "Effective preconditioners for large integral-equation problems," European Conference on Antennas and Propagation (EuCAP 2007), Edinburgh, UK, Nov. 2007.

  134. 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.

  135. 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.

  136. Ö. Ergül and L. Gürel, "Solution of large-scale scattering problems with the multilevel fast multipole algorithm parallelized on distributed-memory architectures," 22nd International Symposium on Computer and Information Sciences (ISCIS07), Ankara, Turkey, Nov. 2007.

  137. 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.

  138. Ö. Ergül and L. Gürel, "Hierarchical parallelization of the multilevel fast multipole algorithm for the efficient solution of large-scale 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.

  139. T. Malas and L. Gürel, "Preconditioning large integral-equation 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.

  140. 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.

  141. Ö. Ergül and L. Gürel "Solutions of electromagnetics problems involving large dielectric objects with the multilevel fast multipole algorithm," in Turkish, URSI-Turkey 2008 Scientific Symposium, Antalya, Turkey, Oct. 2008.

  142. A. Ünal, Ö. Ergül and L. Gürel "Investigation of complicated metamaterial structures with parallel multilevel fast multipole algorithm," in Turkish, URSI-Turkey 2008 Scientific Symposium, Antalya, Turkey, Oct. 2008.

  143. 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, URSI-Turkey 2008 Scientific Symposium, Antalya, Turkey, Oct. 2008.

  144. B. Tiryaki, A. Ünal, Ö. Ergül and L. Gürel "Computations and comparisons of radar-cross-section values of various airborne targets by using parallel multilevel fast multipole algorithm," in Turkish, URSI-Turkey 2008 Scientific Symposium, Antalya, Turkey, Oct. 2008.

  145. Ö. Ergül and L. Gürel "Hierarchical parallelization of MLFMA for the efficient solution of large-scale electromagnetics problems," Vth International Workshop on Electromagnetic Wave Scattering (EWS), Antalya, Turkey, Oct. 2008.

  146. T. Malas and L. Gürel "Iterative Block Near-Field Preconditioners for Surface Integral-Equation Formulations of Dielectric Problems," Vth International Workshop on Electromagnetic Wave Scattering (EWS), Antalya, Turkey, Oct. 2008.

  147. Ö. Ergül and L. Gürel "Field-based-stabilized combined tangential formulation for the accurate solution of scattering problems involving low-contrast dielectric objects," Vth International Workshop on Electromagnetic Wave Scattering (EWS), Antalya, Turkey, Oct. 2008.

  148. 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.

  149. P. Yla-Oijala, 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.

  150. T. Malas and L. Gürel, "An effective preconditioner based on the Schur complement reduction for integral-equation 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.

  151. T. Malas and L. Gürel, "Scalable parallelization of the sparse-approximate-inverse (SAI) preconditioner for the solution of large-scale integral-equation problems," 2009 IEEE International Symposium on Antennas and Propagation and 2009 USNC/URSI National Radio Science Meeting, Charleston, South Carolina, USA, June 2009.

  152. 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.

  153. 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.

  154. Ö. Ergül and L. Gürel, "Preconditioned MLFMA solution of multiple dielectric-metallic composite objects with the electric and magnetic current combined-field 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.

  155. Ö. Ergül and L. Gürel, "Numerical analysis of three-dimensional frequency-selective structures using the multilevel fast multipole algorithm," 23rd Biennial Conf. on Numerical Analysis, Glasgow, UK, June 2009.

  156. Ö. Ergül and L. Gürel, "Fast and accurate solutions of extremely large scattering problems involving three-dimensional canonical and complicated objects," Computational Electromagnetics Workshop (CEM’09), Izmir, Turkey, July 2009.

  157. A. Manyas, Ö. Ergül, and L. Gürel, "Hybridizing physical optics with MLFMA for efficient scattering computations of three-dimensional complex targets," Computational Electromagnetics Workshop (CEM’09), Izmir, Turkey, July 2009.

  158. Ö. Ergül, T. Malas, S. Kılınc, S. Sarıtas, and L. Gürel, "Analysis of photonic-crystal problems with MLFMA and approximate Schur preconditioners," Computational Electromagnetics Workshop (CEM’09), Izmir, Turkey, July 2009.

  159. 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.

  160. Ö. Ergül and L. Gürel, "Fast and accurate analysis of complicated metamaterial structures using a low-frequency multilevel fast multipole algorithm," International Conference on Electromagnetics in Advanced Applications (ICEAA), Torino, Italy, Sept. 2009.

  161. L. Gürel and Ö. Ergül "Rigorous solutions of large-scale scattering problems discretized with hundreds of millions of unknowns," International Conference on Electromagnetics in Advanced Applications (ICEAA), Torino, Italy, Sept. 2009.

  162. Ö. Ergül, A. Arslan-Ergül, and L. Gürel "Rigorous solutions of scattering problems involving red blood cells," European Conference on Antennas and Propagation (EuCAP 2010), Barcelona, Spain, April 2010.

  163. 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.

  164. 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.

  165. 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.

  166. Ö. Ergül and L. Gürel, "An efficient parallel implementation of the multilevel fast multipole algorithm for rigorous solutions of large-scale scattering problems," EMTS 2010 International Symposium on Electromagnetic Theory, Berlin, Germany, Aug. 2010.

  167. D. Doğan, M. E. İnal, A. Manyas, and L. Gürel, "Validation of RCS reduction with radar absorbing materials on canonical geometries," in Turkish, URSI-Turkey 2010 Scientific Symposium, NCTR, Aug. 2010.

  168. L. Gürel and Ö. Ergül, "LL basis functions: half-order 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.

  169. L. Gürel, "Solutions of extremely large integral-equation 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.

  170. 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.

  171. 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.

  172. 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 (AT-CEM’11), Glasgow, Scotland, UK, June 2011.

  173. 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, June-July 2011.

  174. 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.

  175. 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.

  176. 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.

  177. 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.

  178. L. Gürel and Ö. Ergül, “Analysis of double-negative materials with the surface integral equations and the multilevel fast multipole algorithm,” Computational Electromagnetics Workshop (CEM’11), İzmir, Turkey, Aug. 2011.

  179. Ö. Ergül and L. Gürel, “Rigorous solutions of large-scale dielectric problems with the parallel multilevel fast multipole algorithm,” XXX URSI General Assembly and Scientific Symposium, Istanbul, Turkey, Aug. 2011.

  180. 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.

  181. Ö. Ergül and L. Gürel, “Parallel-MLFMA solutions of large-scale problems involving composite objects,” 2012 IEEE International Symposium on Antennas and Propagation and USNC-URSI National Radio Science Meeting, Chicago, Illinois, USA, July 2012.

  182. L. Gürel, “Efficient parallelization of the multilevel fast multipole algorithm (MLFMA),” 2012 Indian Antenna Week (IAW), Gangtok, India, May 2012.

  183. L. Gürel, “Solution of extremely large integral-equations in computational electromagnetics,” 2012 Indian Antenna Week (IAW), Gangtok, India, May 2012.

  184. 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.

  185. L. Gürel, “Accuracy considerations for the integral-equation solutions of some canonical problems,” INTELECT 2012, 6th LEMA-EPFL One-Day Workshop on Integral Techniques for Electromagnetics, Sevilla, Spain, October 2012.

  186. 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.

  187. Ö. Ergül and L. Gürel, “A web-based tool for benchmarking the accuracy of solutions of some canonical electromagnetics problems,” European Conference on Antennas and Propagation (EuCAP 2013), Gothenburg, Sweden, April 2013.

  188. L. Gürel, “A Parallel-MLFMA 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.

  189. 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.

  190. M. Hidayetoğlu, B. Karaosmanoğlu, and L. Gürel, “Reducing MLFMA memory with out-of-core implementation and data-structure parallelization,” Computational Electromagnetics Workshop (CEM’13), İzmir, Turkey, Aug. 2013.

  191. M. Kazempour and L. Gürel, “Solution of low-frequency electromagnetics problems using hierarchical matrices,” Computational Electromagnetics Workshop (CEM’13), İzmir, Turkey, Aug. 2013.

  192. A. Etminan and L. Gürel, “Microwave imaging of three-dimensional conducting objects using the newton minimization approach,” Computational Electromagnetics Workshop (CEM’13), İzmir, Turkey, Aug. 2013.

  193. 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.

  194. L. Gürel, “Fast multipole methods in service of various scientific disciplines,” 2014 IEEE International Symposium on Antennas and Propagation and USNC-URSI National Radio Science Meeting Memphis, TN, USA, July 2014.

  195. 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 USNC-URSI National Radio Science MeetingMemphis, TN, USA, July 2014.

  196. Aslan Etminan and L. Gürel, “Shape reconstruction of three-dimensional conducting objects via near-field measurements,”2014 IEEE International Symposium on Antennas and Propagation and USNC-URSI National Radio Science Meeting Memphis, TN, USA, July 2014.

  197. Mert Hidayetoğlu and L. Gürel, “MLFMA memory reduction techniques for solving large-scale problems,” 2014 IEEE International Symposium on Antennas and Propagation and USNC-URSI National Radio Science Meeting Memphis, TN, USA, July 2014.

  198. 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 USNC-URSI National Radio Science Meeting Memphis, TN, USA, July 2014.

  199. Manouchehr Takrimi and L. Gürel, “A modified equivalence principle for open surfaces,”2014 IEEE International Symposium on Antennas and Propagation and USNC-URSI National Radio Science Meeting Memphis, TN, USA, July 2014.

  200. Aslan Etminan, Alireza Sadeghi, and L. Gürel, “Electromagnetic Imaging of Three-Dimensional Dielectric Objects with Newton Minimization,” 2014 IEEE International Symposium on Antennas and Propagation and USNC-URSI National Radio Science Meeting Memphis, TN, USA, July 2014.