Main speaker, Wavelet Applications in Industrial Processing V, SPIE International Symposium on Optics East 2007, Boston, MA, USA, September 9--12, 2007.

Plenary Speaker, Annual Colloquium of the Tunisian Mathematical Society 2007, Sousse, Tunisia, March 19--22, 2007.

Invited speaker, February Fourier Talks, The Norbert Wiener Center for Harmonic Analysis and Applications, Maryland, February 15--16, 2007.

Plenary Speaker, International Conference on Harmonic Analysis and Applications in San Luis Argentina, July 31--August 5, 2006.

Plenary speaker, Wave 2006, Bernoulli Center, EPFL, Lausanne, Swtitzerland, July 110-14, 2006.

Plenary Speaker, International Conference Harmonic Analysis and Applications, * Encuentro Nacional de Analistas A.P. Calderon, Merlo, San Luis, Argentina, 2006.

Keynote speaker, Wavelet XI, SPIE San Diego, July 31-August 4, 2005.

Two days lectures on “Wavelet frames on irregular grids and non-harmonic Gabor systems", Workshop on Wavelets, Frames and Operator Theory, June 23, July 2, 2003, University of Colorado Boulder.

Main speaker, The Second International Symposium on Computing Science, 20-23, 2002, Guangzhou, China.

Plenary Speaker, International Conference on Wavelets and their Applications, Jan. 4-5, 2002, Anna university, Madras, India.

Invited Speaker, Workshop on Wavelet Frames and Operator Theory, July 15-20, 2002, Texas A&M, College Station.

Invited Speaker, International Conference on Applied and Computational Harmonic Analysis, June, 4-8, 2001, City University of Hong Kong, Hong Kong, China.

Plenary Speaker, International Conference on Image and Signal Processing, May 3-5, 2001, Sgadir Morocco.

Plenary Speaker, Joint IDR-IMA Workshop: Ideal Data Representation, Institute for Mathematics and Its Applications, April 9-13, 2001, University of Minneapolis, Minnesota.

Main Speaker, International Conference on Wavelet Analysis and its Applications, Nov. 15-20, 1999, Zhongshan Univ., Guangzhou, China.

Main Speaker, Conference on Harmonic Analysis and Applications, University of Maryland, College Park, October 7-9, 1999.

Plenary Speaker, Workshop on Wavelets in Signal Processing and Biomedical Applications, The National University of Singapore, December 21-22, 1998.

Main Speaker, Wavelet and Applications Workshop, Swiss Science Foundation, Centro Stehpano Francini, Monte Verita, Ticino, Switzerland Sept. 28-Oct.2, 1998.

Main Speaker, Workshop on Spectral Methods in Medical Signal Processing, Institut fur biomathematik und Gesundheit GmbH, Feb. 29-March 1, 1998, Munich.

Plenary Speaker, Workshop on Mathematics Applied to Industry, August 18-29, 1997, Mar del Plata Argentina.

Main Speaker, International Conference on Mathematical Models in Medical and Health Sciences, invited speaker, May 28-30, 1997, Nashville, TN.

Main Speaker, International Conference on Dynamical Systems, "DYNAMIC DAYS," Ecole Normale Superieure de Lyon, France, Dynamic Days 1996, Jully 11, 1996.

Main Speaker, Conference in Honor of Professor Richard MacCamy, Department of Mathematics, Carnegie-Mellon University, PA, August 17, 1995.

Main Speaker, Primer Coloquio Latinamericano de matematica aplicada a la Industria y la Medicina, Buenos Aires, Argentina, December 1995.

Main Speaker, Workshop on Wavelets, Department of Mathematics, Univ. of Vienna, Austria, March 6 and March 8, 1993.

Invited Speaker, Special Issue on Wavelets, frames and Related expansions, AMS sectional meeting Organ, November 11-13, Eugene Oregon,2005.

Seminar Speaker, Dept of mathematics Univerity of Washington at Saint Louis, January 22, 2005.

Colloquium Speaker, Dept of mathematics Univerity of Washington at Saint Louis,January 21, 2005.

Speaker at the mini-workshop “wavelet and frames”, Mathematisches Forschungsinstitut Oberwolfach, Lorenzenhof, Oberwolfach-Walke, Germany, February 15, 21, 2004.

Invited speaker, special session “Wavelets, frames and operator Theory”, Annual Meeting of the Amer. Math. Soc., January 15-18, 2003, Baltimore.

Invited speaker, special session “Inverse Problems and Sampling Theory in Signal Analysis”, Annual Meeting of the Amer. Math. Soc., January 15-18,  2003, Baltimore.

Invited speaker, International Conference on Sampling Theory and Applications, May, 13-17, 2001, UCF, Orlando, Florida.

Invited speaker, Special session "Interaction of inverse problems and image analysis," Annual Meeting of the Amer. Math. Soc., January 10-13, 2001, New Orleans.

Invited speaker, Special session "Integral Transforms," Annual Meeting of the Amer. Math. Soc., January 10-13, 2001, New Orleans.

Invited speaker, Special session on "Computational wavelet analysis," American Mathematical Society meeting, September 23-24, 2000, Toronto, Canada.

Invited Speaker, International Association for Mathematics and Computers Simulation Conference, Special Session in honor of Gilbert Walter, Milwaukee, Wisconsin, May, 25-27, 2000.

Invited Speaker, Workshop on "Wavelets and its Applications," Georgia Tech, April 21, 2000.

Colloquium, Department of Mathematics, Texas A&M, April 26, 2000.

Colloquium, UCLA, February 22, 2000.

Invited speaker for the session "Mathematical Models for Physiology," SIAM Annual Meeting, Rio Grande, Puerto Rico, July 10-14, 2000.

Invited speaker for the session "Mathematics in Image Formation and Processing," SIAM Annual Meeting, Rio Grande, Puerto Rico, July 10-14, 2000.

Invited speaker for the session "New Advances in Medical Imaging," Fourth International Congress on Industrial and Applied Mathematics, July 5-9, Edinburgh, Scotland, 1999.

Invited Speaker for the mini symposium "Wavelets and their Applications," Society of Industrial and Applied Mathematics, May 10-12, 1999, Atlanta, Georgia.

Invited speaker for the session "Functional and Harmonic Analysis of Wavelets," Annual Meeting of the American Mathematical Society, San Antonio, Texas 1999.

Colloquium, Institut National de la Recherche Informatique et de Controle (INRIA), November 27, 1997, Paris, France.

Colloquium, Mathematics Dept., Ecole Poly technique de Paris, France, December 1, 1997.

Invited speaker, American Mathematical Society Summer Seminars on Numerical Analysis, Utah, Aug.9, 1995.

Colloquium, Department of Mathematics, University of William and Mary, Virginia, March 20 1995.

Colloquium, Department of Electrical Engineering, University of Virginia, Charlotsville, Feb. 20, 1995.

Colloquium, Department of Mathematics, Univ. of Indiana, Indianapolis, November 12, 1993.

Colloquium, Department of Mathematics, Univ. of Delaware, Newark, April 23, 1993.

Colloquium, Department of Mathematics, Carnegie-Mellon Univ., Pittsburgh PA, November 6, 1992.

Colloquium, Department of Mathematics, Univ. of Pittsburgh, Pittsburgh PA, November 4, 1992.

Colloquium, Department of Mathematics, Univ. of South Carolina, Columbia SC, October 30, 1992.

Invited presentation, GE Corporate Research and Development, Schenectady New York, May 6, 1992.

Department of Mathematics, American Univ., March 3, 1992.

Invited presentation, GE Corporate Research and Development, Schenectady New York, November15, 1991.

Colloquium, Department of Mathematics, Univ of Maryland at Baltimore County, September 20, 1991.

Colloquium, Department of Mathematics, University of Toledo, May 15, 1991.