Dr. John Sadowsky

Computer Science

Current Courses

Personal Bio

Dr. Sadowsky has been a member of the adjunct faculty of the Whiting School of Engineering since 1981. He is a senior principal professional research mathematician with Signalscape Incorporated, of Cary, North Carolina, specializing in computational signal processing techniques and algorithms, parameter estimation, pattern recognition, sensory engineering, and speech processing. He received his B.A. in mathematics from the Johns Hopkins University and his Ph.D. from the University of Maryland, College Park, in number theory, as a student of W. W. Adams and an academic descendant of K. Gauss. He has a wide range of interests, including number theory, signal processing, computational complexity, algorithm design and analysis, information theory, computational algebraic geometry, statistical decision theory and inference, cryptology, computational graph theory, and sensory engineering (the science of virtual reality.) He is also a professional actor and stage director in the Washington/Baltimore area (Pumpkin Theater, Landless Theater Company, various films, etc.) and is a director and actor with the Company of the Rose at the Maryland Renaissance Festival.

Education History

  • Ph.D. Mathematics, University of Maryland

Work Experience

Senior Principal Engineer, Signalscape, Incorporated

Publications

NSA Modeling and Simulation: Validation Practices and Procedures, D. Gregg, J. Sadowsky, March, 1999

"Adaptive Design of Wavelets for Continuous and Discrete Wavelet Transforms to Determine Features in Signals," Sadowsky, J., Proceedings of the 32nd Annual Conference on Information Sciences and Systems, Princeton University, Princeton, New Jersey, March 18-20, 1998

“Review of Applied Neural Networks for Signal Processing by Fa-Long Luo and Rolf Unbehauven,” Sadowsky, J, International Journal of Neural Systems, World Scientific, 1998

“Constant Envelope Wavelet Modulation,” Holland, R.L., Jordan, M.A., Nichols, R.A., Jones, S.D., Jensen, J.R., Bokulic, R.S., Edwards, M.L., Sadowsky, J., Sullivan, M.D., and Tornatore, H.G., APL Technical Memorandum VS-97-042, May, 1997

“Direct Numerical Simulation of Electromagnetic/Rough Surface and Sea Scattering by an Improved Banded Matrix Iterative Method,” D.J. Donohue, H.-C. Ku, D.R. Thompson, and J. Sadowsky, The Johns Hopkins University Technical Digest, Vol. 18, No. 2, 1997

“A Subway Platform Edge and Train Car Door Detection System for the Blind,” J. Sadowsky,J. L. Abita, R. P. Aylor, G. A. Barney,J. Bohandy,B. G. Carkhuff, K. L. Josephson,B. A. Klem,S. J. Mobley,E. B. Morris,J. F. Rider, W. Schneider,R. L. Stanford, and S. F. Wilderson, The Johns Hopkins University Technical Digest, Vol. 18, No. 2, 1997

The Continuous Wavelet Transform and Variable Resolution Time-Frequency Analysis,” A.-H. Najmi and J. Sadowsky, The Johns Hopkins University Technical Digest, Vol. 18, No. 1, pp. 134-140, 1997

“An Investigation of Signal Characteristics using the Continuous Wavelet Transform,” J. Sadowsky, The Johns Hopkins University Technical Digest, Vol. 17, No. 3, 258-269, 1996

“A Multidivisional Graduate Curriculum for Sensory Engineering; The Science of Synthetic Environments,” J. Sadowsky, invited talk to the Joint Meeting of the New York State Section of the American Physical Society and the American Association of Physics Teachers, Yorktown Heights, New York, April 12-13, 1996.

"Feasibility of Superresolution Techniques to Resolve the Problem of Multipath," J. Sadowsky, JHU/APL Technical Report RSI-95-002, February, 1995

"A Synthetic Environment System for Planning, Education, and Data Visualization," J. Sadowsky, D. Weintraub, I. Feldberg, and S. Diamond, Proceedings of the Twenty-Eighth Annual Asilomar Conference on Signals, Systems, and Computers, Maple Press,1994, pp. 1367-1371

"Multidivisional Graduate Education Program in Sensory Engineering", J. Sadowsky and R. Massof, Proceedings of the Twenty-Eighth Annual Asilomar Conference on Signals, Systems, and Computers, Maple Press, 1994, pp. 1325-1329

"The Continuous Wavelet Transform: A Tool for Signal Investigation and Understanding," J. Sadowsky, The Johns Hopkins University Technical Digest, Vol. 15, No. 4, Nov., 1994, pp. 306-318

"Guest Editor's Introduction: Special Issue on Synthetic Environments," J. Sadowsky, The Johns Hopkins University Technical Digest, Vol. 15, No. 2, June, 1994, pp. 96-98

"Sensory Engineering: The Science of Synthetic Environments," J. Sadowsky and R. Massof, The Johns Hopkins University Technical Digest, Vol. 15, No. 2, June, 1994, pp. 99-109

“Review of Neural Networks: A Tutorial, by Michael Chester,” J. Sadowsky, ACM Computing Reviews, March 1994

"The Role of Applied Mathematics in Sensory Engineering," J. Sadowsky, Sensory Engineering Conference, The Johns Hopkins University, June, 1993

"An Algorithm for Estimating the Frequency of a Subsampled Signal, Using the Chinese Remainder Theorem," J. Sadowsky and D. Maurer, Proceedings of the Twenty-Seventh Conference on Information Sciences and Systems, Johns Hopkins University, March, 1993, pp. 645-649

"Number Theory for the Working Fractologist," J. Sadowsky, Maryland Dynamics Seminar, University of Maryland, College Park, June, 1992

"Time and Frames of Reference for Spacecraft Position and Attitude in the MSX Operations System," J. Sadowsky, JHU/APL Technical Report RMI-92-012, April, 1992

"An Interpolation Algorithm for the MSX Spacecraft Position Data," J. Sadowsky, JHU/APL Technical Report RMI-92-011, March, 1992

"Recommendation for the Orbital Prediction Software for MSX Mission Planning," J. Sadowsky, JHU/APL Technical Report RMI-92-008, March, 1992

"Infrared Sensor Availability Based on Computations of Probability of Cloud-Free Line-of-Sight Using the NAAWS Database," J. Sadowsky, JHU/APL Technical Report RMI-92-006, January, 1992

"Calculations of Probability of Cloud-Free Line-of-Sight (PCFLOS)," J. Sadowsky, JHU/APL Technical Report RMI-92-001, January, 1992

"Signal and Image Analysis Using the Wavelet Decomposition," First Symposium on Research and Development at the Applied Physics Laboratory, November, 1991

"The Number of Relatively Prime Solutions to a Diophantine Approximation of Hurwitz Numbers," J. Sadowsky, American Mathematical Society, Orono, Maine, August, 1991

"A Neural Network for Adaptive Surfaces and Closed Decision Boundaries," I. Bankman, J. Sadowsky, and V. Sigillito, Proceedings of the Twenty-fifth Conference on Information Sciences and Systems, Johns Hopkins University, March, 1991, pp. 848-853

"Neural Network Analysis of Images for Non-Destructive Evaluation", J. Sadowsky, I. Bankman, and V. Sigillito, Proceedings of the Twenty-Fourth Annual Asilomar Conference on Signals, Systems, and Computers, Maple Press, 1990, pp. 562-569

"Spectral Properties of the Weil Transforms," J. Sadowsky, Proceedings of the Conference on Information Sciences and Systems, Princeton University, March, 1990,
pp. 676-678

"Description of Attitude Data Files for the Delta Star Events," J. Sadowsky, T. Englar, and F. Murray, APL Technical Memorandum S3G-90-032, February, 1990.

"Applications of Weil Representation Theory to Signal Processing," J. Sadowsky, Proceedings of the Twenty-Third Annual Asilomar Conference on Signals, Systems, and Computers, 1989, Maple Press, pp. 628-632

"Assessment of the GAPP Systolic Chip for Use in Computationally Intensive Signal Processing," J. Craig, J. Katzin, and J. Sadowsky, Second SIAM Conference on Parallel Processing for Scientific Computing, 1985

"An Upper Bound in Asymptotic Diophantine Approximation with Reduced Fractions," J. Sadowsky, Annual Meeting of the American Mathematical Society, San Francisco, California, Jan. 1981

Asymptotic Diophantine Approximations with Reduced Fractions, J. Sadowsky, the University of Maryland, 1980

"Addresses in Computer Data Files Which are Ordered as Lattices," J. Sadowsky, Annual Meeting of the American Mathematical Society, Biloxi, Mississippi, Jan. 1979

Honors and Awards

  • Walter G. Berl Technical Publication Award (1998)

Professional Organizations

AMS