Friday, May 1, 1992 3:00 p.m. Michalakis A. Averkiou “Propagation of pulsed finite amplitude sound beams in a liquid with strong absorption” Michalakis A. Averkiou “Reflection of focused sound beams from curved surfaces” Bart Lipkens “The propagation of plane N waves through a statistically isotropic turbulent field as a singular perturbation problem” Douglas E. Reckamp…
Friday, April 24, 1992 3:00 p.m. James A. Hawkins, Jr. Mechanical Engineering The University of Texas at Austin We have developed, using Hamilton’s variational principle, a model which describes the propagation of acoustical disturbances (sound) in bubbly sediments. The sediment is taken to be a solid frame saturated by a fluid (in the sense of…
Friday, April 10, 1992 4:00 p.m. Jack B. Evans, P.E. Jack Evans & Associates, Inc. Engineered Vibration Acoustic & Noise Solutions Building design criteria and construction parameters, with a focus on environmental noise from mechanical equipment, including engineer generators, fire pumps and cooling towers will be presented. Case histories will be discussed, including on-site observations…
Friday, April 3, 1992 4:00 p.m. Inder Makin Biomedical Engineering The University of Texas at Austin The talk will present a model for second harmonic generation in a focused Gaussian beam that is reflected and transmitted at a slightly curved interface. Second harmonic generation is a nonlinear effect that accompanies waveform distortion at sufficiently high…
Friday, March 13, 1992 4:00 p.m. Randy M. Roberts Department of Physics The University of Texas at Austin The underwater spark is being investigated as a practical source of intense, low frequency sound. The spark generates an oscillating bubble which produces intense sound with a fundamental frequency corresponding to the bubble’s period. The acoustic energy and…
Friday, March 6, 1992 4:00 p.m. Jeffrey A. Cook Applied Research Laboratories and Department of Physics The University of Texas at Austin Spark discharges have been used for many years as a source of sound and high pressures. Previous research on spark-generated bubbles has been concerned primarily with the dynamics of a single bubble. Multiple…
Friday, February 28, 1992 4:00 p.m. Dr. Mark Hamilton Department of Mechanical Engineering The University of Texas at Austin Lithotripters use focused shock waves to disintegrate kidney stones and gallstones. One way to generate the shock wave is with a spark source at the near focus of an ellipsoidal mirror. The acoustic energy in the…
Friday, February 21, 1992 4:00 p.m. Bart Lipkens Applied Research Laboratories and Department of Mechanical Engineering The University of Texas at Austin Typical measured sonic boom rise times are two to five times longer than rise times calculated using molecular relaxation theory [J. Kang, Ph.D. thesis, Pennsylvania State University (May 1991); A. D. Pierce and…
Friday, February 7, 1992 4:00 p.m. Nathan Kane Department of Mechanical Engineering The University of Texas at Austin In this seminar, the ringing that results from rubbing a wine glass rim with a wet finger is investigated. Normally, only one tone, corresponding to the fundamental of the glass, can be produced by rubbing a glass…
Friday, January 31, 1992 4:00 p.m. Dr. Mark F. Hamilton Department of Mechanical Engineering The University of Texas at Austin Although the study of nonlinear acoustics predates nonlinear optics by more than a century, nonlinear optics has been exploited much more for technological applications than has nonlinear acoustics. The main difference is dispersion (dependence of…
Monday, December 2, 1991 3:00 p.m. D. C. Teas KRUG Life Sciences, Inc. and Kent K. Gillingham Armstrong Laboratory, Brooks AFB, TX Spatial disorientation accounts for a substantial percentage of aircraft accidents and nearly all such accidents are fatal. Pilots also report experiencing disorientation during flight without losing control of their aircraft. When disorientation is…
Monday, November 18, 1991 3:00 p.m. John Post Electrical & Computer Engineering Department The University of Texas at Austin To study the throat impedance of a JBL constant directivity horn, a new acoustic impedance measurement system has been developed. This system will be presented along with supporting data from the horn measurements. Additional applications will…
Monday, November 11, 1991 3:00 p.m. Dr. Konstantin A. Naugol’nykh Andreev Acoustical Institute USSR Academy of Sciences Moscow No abstract available.
Monday, October 28, 1991 3:30 p.m. Bart Lipkens Applied Research Laboratories The University of Texas at Austin This talk is a “dry run” for a paper which will be given at the Acoustical Society of America Meeting in Houston, Texas, November 4-8 1991.
Monday, October 28, 1991 3:00 p.m. James A. Ten Cate Department of Mechanical Engineering Applied Research Laboratories The University of Texas at Austin This talk is a “dry run” for a paper which will be given at the Acoustical Society of America Meeting in Houston, Texas, November 4-8 1991.
Friday, October 25, 1991 3:00 p.m. Leick D. Robinson Applied Research Laboratories The University of Texas at Austin One of the primary obstacles to NASA’s proposed High Speed Civil Transport is the sonic boom produced by the aircraft. Features of the sonic boom that are of primary importance are the amplitude and rise time of…
Monday, October 14, 1991 3:00 p.m. Aubrey L. Anderson Department of Oceanography Texas A & M University Remote sensing characterization of seafloor sediments with acoustic systems is a long standing goal of acoustical oceanographers. Recent results of measurements with side scan sonars and chirp sonars are encouraging. A major complication in the interpretation of such…
Monday, October 7, 1991 3:00 p.m. Noel A. Adorno and E. L. Hixson Department of Electrical and Computer Engineering The University of Texas at Austin A focused microphone array in the headliner of a car could provide a “no hands” cellular system microphone. The usually installed stereo could provide the receiver. The focal volume should…
Monday, September 30, 1991 3:00 p.m. Professor E. A. Zabolotskaya General Physics Institute USSR Academy of Sciences Moscow This seminar will provide an overview of the history, structure, and research areas of the General Physics Institute of the USSR Academy of Sciences. The Institute is composed of 10 Departments (e.g., Wave Phenomena, Microelectronics, Solid State…
Friday, September 20, 1991 12:00 p.m. Dr. Timothy S. Margulies U.S. Nuclear Regulatory Commission Washington, D.C. The theoretical prediction of acoustic wave propagation in fluids is important for understanding medical diagnostic techniques, ocean and other geophysical transmission characteristics; as well as, for measuring physio-chemical properties of fluids, and for estimating equations of state. The purpose…