Refereed Journals:

S. Ramakrishnan, S. Udpa and L. Udpa, “Performance of Source Localization algorithms in detection of intrathoracic acoustic sources,” 2009 (in preparation).

S. Ramakrishnan, S. Udpa and L. Udpa, “A viscoelastic finite-difference time-domain model of sound propagation in human thorax,” submitted to Journal of the Acoustical Society of America, 2009 (under review).

S. Ramakrishnan and S. Udpa, “ Comments on ‘Detection of Distributed Sources Using Sensor Arrays’,” IEEE Transactions on Signal Processing, Vol. 55, Issue 6, Part 1, pp. 2757-2758, June 2007.

Y. Tian, S. S. Udpa, N. Nair and S. Ramakrishnan, “Modeling of Electromagnetic Heating Effects During “In-Vivo” Testing of Prosthetic Heart Valves,” IEEE Transactions on Magnetics, Vol. 42, Issue 10, pp. 3563-3565, October 2006.

S. C. Chan, R. Clifford, S. Majumdar, N. Nair, S. Ramakrishnan, Y. Li, P. Ramuhalli, L. Udpa and S. S. Udpa, "Novel methods for detecting fractures in prosthetic heart valves," Insight: Nondestructive Testing and Condition Monitoring, Vol. 47, No. 1, pp. 15-19, January 2005.

P. Xiang, S. Ramakrishnan, X. Cai, P. Ramuhalli, R. Polikar, S. S. Udpa and L. Udpa, "Automated analysis of rotating probe multi-frequency eddy current data from steam generator tubes," Intl. J. Applied Electromagnetics and Mechanics, Vol. 12, No. 3/4, 2001, pp. 151-164.

 

Conference Proceedings:

S. Ramakrishnan, S. Udpa and L. Udpa, “A Numerical Model to study Auscultation Sounds under Pneumothorax conditions,” accepted to be published in Proceedings of 31st Annual International Conference of IEEE Engineering in Medicine and Biology (EMBC), 2009.

S. Ramakrishnan, S. Udpa and L. Udpa, “A numerical model simulating sound propagation in human thorax,” accepted to be published in Proceedings of IEEE International Symposium on Biomedical Imaging (ISBI), 2009.

Z. Zeng, N. Lei, S. Majumdar, S. Ramakrishnan, C. E. Bardel, P. Lekeakatakunju, P. Ramuhalli, L. Udpa and T. Bipes, “Simulation of eddy current steam generator tube testing in nuclear power plants,” accepted to be published in Proceedings of Electromagnetic Nondestructive Evaluation (ENDE), 2009.

J. Benson, O. Udebhoo, R. K. Dayana, S. Ramakrishnan, S. Majumdar, P. Ramuhalli, L. Udpa and S. Udpa, “Automated Analysis Systems for Characterizing Eddy Current SG Inspection Data,” Proceedings of International Society of Electromagnetics and Mechanics (ISEM 2007), pp. 157-158, Sept. 2007.

S. Majumdar, S. Ramakrishnan, N. Nair, S. C. Chan, R. Clifford and S. S. Udpa, “A Modified FFT Algorithm for Efficient Computation of Narrow Band Spectrum,” IEEE International Conference on Electro Information Technology (EIT 2006), East Lansing, MI May 2006.

N. V. Nair, V. R. Melapudi, S. Ramakrishnan, L. Udpa, S. S. Udpa and W. P. Winfree, “A Wavelet Based Signal Processing Technique for Image Enhancement in Terahertz Imaging Data,” Review of Quantitative Nondestructive Evaluation, D. O. Thompson and D. E. Chimenti, Eds., American Institute of Physics, 2005.

S. Ramakrishnan, N.V. Nair, R. Clifford, S. Majumdar, S. C. Chan, Y. Li, P. Ramuhalli, L. Udpa and S. Udpa, “An Electromagnetic Acoustic Transduction Technique for Detecting Strut Fractures in Artificial Heart Valves,” IEEE International Conference on Electro Information Technology (EIT 2005), Lincoln, NE, May 22-25, 2005.

N.V. Nair, S. Ramakrishnan, R. Clifford, Y. Li, S. Majumdar, S. C. Chan, P. Ramuhalli, L. Udpa and S. S. Udpa, “A Beat Frequency Electromagnetic Acoustic Transduction Technique for Detecting Strut Fractures in Prosthetic Heart Valves,” Proceedings of Electromagnetic Nondestructive Evaluation (ENDE 2004), Studies in Applied Electromagnetics and Mechanics, IOS press, Vol. 25, 2005.

S. C. Chan, M. Oka, R. Clifford, S. Majumdar, N. Nair, S. Ramakrishnan, Y, Li, P. Ramuhalli, L. Udpa, and S. S. Udpa, “In Vitro Testing of a System for the Evaluation of Prosthetic Heart Valves,” Proceedings of Electromagnetic Nondestructive Evaluation (ENDE 2004), Studies in Applied Electromagnetics and Mechanics, IOS press, Vol. 25, 2005.

N V Nair, S Ramakrishnan, S T Thomas, R Ahn, L Udpa and S S Udpa, "Signal Processing Techniques for Detecting Strut Fractures in Prosthetic Heart valves," International Conference on Eddy Current Non Destructive Evaluation (ENDE 2003), Paris, France, May 2003.

S Ramakrishnan, S T Thomas, N V Nair, S S Udpa and K Balasubramaniam, "An Electromagnetic Acoustic Technique for Non-Invasive Defect Detection in Mechanical Prosthetic Heart valves," National Seminar of the Indian Society for Non Destructive Testing, NDE 2002, December 2002.

 

Presentations:

S. Ramakrishnan, S. Udpa and L. Udpa, “An acoustic FDTD model of human thorax to develop multi-sensor techniques for noninvasive detection of thoracic pathologies,” First International Symposium on Audible Acoustics in Medicine and Physiology, Sept 8-9 2008. (poster)

S. Ramakrishnan, S. Majumdar, P. Ramuhalli, L. Udpa, and S. Udpa, "Eddy Current AutoAnalysis Software Demonstration," EPRI Technical Advisory Group Meeting, Hyatt Regency Austin, TX, June 9, 2008.

Y. Tian, S. S. Udpa, N. Nair and S. Ramakrishnan, “Modeling of Electromagnetic Heating Effects During “In-Vivo” Testing of Prosthetic Heart Valves”, IEEE International Magnetics Conference, San Diego, CA, May 8-12, 2006.

N.V. Nair, S. Ramakrishnan, R. Clifford, Y. Li, S. Majumdar, S. C. Chan, P. Ramuhalli, L. Udpa and S. S. Udpa, “A Beat Frequency Electromagnetic Acoustic Transduction Technique for Detecting Strut Fractures in Prosthetic Heart Valves,” International Workshop on Electromagnetic Nondestructive Evaluation, East Lansing, MI, June 1-2, 2004.

S. Ramakrishnan, S. Mukherjee, S. Soo, J. Chen, P. Ramuhalli, L. Udpa, and S. Udpa, "Eddy Current AutoAnalysis Software Demonstration," Palo Verde Nuclear Power Plant, Phoenix, AZ, 2003.

S. Ramakrishnan, P. Ramuhalli, L. Udpa, and S. Udpa, "Eddy Current AutoAnalysis Matlab GUI Demonstration," San Onofre Nuclear Generating Station, San Diego, CA, 2002.

Invited Conference Presentations (Assisted in Preparation):

S. S. Udpa, S. C. Chan, R. Clifford, S. Majumdar, N. Nair, S. Ramakrishnan, P. Ramuhalli, A. Surapur, L. Udpa, and A. White, “Active and Passive Methods for Detecting Strut Fractures in Prosthetic Heart Valves,” V. S. Joshi Memorial Plenary Lecture, NDE 2004, Pune, India, December 9-11, 2004.

S. C. Chan, R. Clifford, S. Majumdar, N. Nair, S. Ramakrishnan, P. Ramuhalli, and S. Udpa, “Detection of Strut Fractures in Artificial Heart Valves,” Invited presentation given at Woosuk University, Jeonju, Korea, October, 2003.

S. Ramakrishnan, S. Mukherjee, S. Soo, J. Chen, U. Parrikar, B. Shin, P. Ramuhalli, L. Udpa and S. Udpa, “Development of Algorithms for Automatic Analysis of Rotating Probe Eddy Current Data,” Invited Presentation to 22nd Annual EPRI Steam Generator NDE Workshop, Hilton Head, SC, June 30 – July 2, 2003.