Forensics and the Acoustical Engineer
Tuesday, March 4, 1997 4:00 p.m. Robert Bruce Collaboration in Science and Technology, Inc. Houston, Texas No abstract available.
Noise Control and Engineering Acoustics at Boeing
Monday, March 3, 1997 4:00 p.m. Dr. Milton Lumpkin Manager, Noise Engineering 737/757 Programs Boeing Corporation Seattle, Washington http://www.boeing.com At Boeing, the Noise Engineering and Noise Laboratory organizations employ approximately 160 people to insure that Boeing aircraft set world class standards for low noise emissions. Our scientists, engineers, and technicians work to reduce the noise…
Mode Extraction from a VLA Using Singular Value Decomposition
Friday, February 21, 1997 4:00 p.m. Tracianne Neilsen Department of Physics The University of Texas at Austin http://www.ph.utexas.edu A method is developed for extracting the depth-dependent mode functions from single-frequency measurements on a vertical line array as a source moves out in range. A matrix of the complex pressure field versus receiver depth and source…
Review of Recent and Ongoing Developments in the Acoustic Treatment of Aerosols
Friday, January 31, 1997 4:00 p.m. Karl Martin Department of Mechanical Engineering The University of Texas at Austin http://www.me.utexas.edu Acoustic agglomeration is the use of high intensity sound to cause aerosol particles to stick together. It is a process with applications in pollution control and bulk materials handling. The acoustic agglomeration effect has been known…
Control of Acoustic Cavitation with Application to Lithotripsy*
Wednesday, December 18, 1996 3:00 p.m. Mike Bailey Department of Mechanical Engineering Control of acoustic cavitation, which is sound-induced growth and collapse of bubbles, is the subject of this dissertation. Application is to extracorporeal shock wave lithotripsy (ESWL), used to treat kidney stones. Cavitation is thought to help comminute stones yet may damage tissue. Can…
Presentations for the Third Joint ASA Meeting Honolulu, Hawaii
Monday, November 25, 1996 4:00 p.m. Frank Boyle Applied Research Laboratories: A Generalized Acoustic Model for Marine Sediments Matias Budhiantho Department of Electrical Engineering: Acoustic Velocity Related Statistical Distributions B. J. Landsberger Department of Mechanical Engineering: Second Harmonic Generation in a Sound Beam Transmitted Through an Isotropic Solid Zhenia Zabolotskaya Department of Mechanical Engineering: Nonlinear…
Propagation of Acoustic Pulses in a Turbulent Medium
Friday, November 15, 1996 4:00 p.m. Dr. Philippe Blanc-Benon Laboratoire de M’ecanique des Fluides et d’Acoustique Ecole Central de Lyon Lyon, France An acoustic wave propagating through a turbulent atmosphere is significantly affected by the variation in the value of the refractive index along the propagation path. The influence of temperature and wind velocity fluctuations…
Point-Source Reciprocity Relations in Elastodynamics and Acoustics
Monday, November 11, 1996 4:00 p.m. Professor C. L. Morfey Institute of Sound and Vibration Research Southampton, United Kingdom The fields of linear elastodynamics and linear acoustics employ somewhat different reciprocity relations for the limiting case of point sources. In acoustics, the volume-velocity source is regarded as basic: The appropriate reciprocity relation is well-known and…
Localization and Delocalization in One-Dimensional Dynamic Systems
Wednesday, November 6, 1996 4:00 p.m. Joe Dickey The Johns Hopkins University Mechanical structures with reasonably periodic variations in impedance may exhibit wave localization similar to Anderson localization in atomic systems. Several such systems have been investigated by the authors: a beaded string, membranes and plates with periodic stiffeners attached, and a “jungle gym” All…
Acoustical Aspects of the Planar Jet Instability
Friday, November 1, 1996 4:00 p.m. Dr. A. Wilson Nolle Department of Physics The spatial growth of the sinuous instability of planar jets has received much attention as the amplification mechanism involved in edge-tone oscillation and in flutelike instruments. Early “temporal” theoretical treatments, used in most discussions of these systems, dealt with an unrealistic oscillation…
Acoustic Correlates to Speech Form the Basis for Perception
Friday, October 25, 1996 4:00 p.m. Wendy A. Castleman Department of Psychology Speech is a fairly continuous stream of acoustical information. However, listeners do not hear speech as continuous. They perceive speech as a string of discrete words, syllables and phonemes. This poses the problem of how listeners are able to segment the stream into…
Modeling and Measurement of Nonlinear Surface Waves*
Monday, October 14, 1996 3:30 p.m. Doug Meegan Applied Research Laboratories The linear theory for small-signal surface waves (Rayleigh, Scholte, and Stoneley) will be reviewed, and conditions for the existence of these modes of propagation will be described. Next, a nonlinear theory for finite-amplitude Stoneley and Scholte waves will be presented. The theory generalizes an…
Lithotripsy: The Breaking of Kidney Stones by Acoustic Shock Waves
Friday, October 4, 1996 4:00 p.m. Dr. Robin Cleveland Applied Physics Laboratory University of Washington at Seattle The use of shock waves to destroy kidney stones has found wide acceptance in hospitals throughout the world. Although over two million successful lithotripsy treatments have occurred, there is still much to be learned about the physical mechanisms…
Techniques for “Collecting Relevant Information Electronically”
Friday, September 20, 1996 4:00 p.m. Susan Ardis Head, McKinney Engineering Library The purpose of this talk is to give students and faculty the scoop (the truth) about libraries and information so that you can get what you want when you want it with grace and ease. This talk will answer several exciting questions including:…
Trends in Electromechanical Transduction
Wednesday, September 11, 1996 4:00 p.m. Dr. Ilene Busch- Vishniac Department of Mechanical Engineering In recent years there has been a growing interest in electromechanical transducers, i.e., sensors and actuators. This increase in interest has been prompted by a number of trends, including: the growing pervasiveness of sensors and intelligence in devices, the increasingly challenging…
Nonlinear Acoustic Nondestructive Testing
Thursday, May 9, 1996 4:00 p.m. Dr. Alexander Sutin Institute of Applied Physics Russian Academy of Science Nizhny Novgorod, Russia Acoustic imaging and NDT methods are widely used in various technical fields. Conventional methods are based on the principles of linear acoustics; nonlinear distortion is ignored. The strength of the distortion can drastically increase due…
Presentations for the 131st Meeting of the Acoustical Society of America
Monday, May 6, 1996 3:30 p.m. Michael R. Bailey “Intensified cavitation produced with pressure release and rigid ellipsoidal reflectors” E. A. Zabolotskaya “Nonlinear surface wave propagation in crystals” David T. Blackstock “R. T. Beyer’s contributions to nonlinear acoustics” Frank A. Boyle “Mapping acoustic echosounder data to human color vision” Penelope Menounou “Propagation of finite-amplitude broadband…
Reading Spark Signatures and Educational Activities of the Acoustical Society of America
Friday, May 3, 1996 4:00 p.m. Dr. Wayne M. Wright Applied Research Laboratories The University of Texas at Austin and Department of Physics Kalamazoo College Kalamazoo, Michigan This presentation will be composed of two parts. The first part will be an illustrated review of opportunities that are provided by modest sparks in air to learn…
Excitation of Shear Waves within Rubber-like Material by Focused Longitudinal Waves
Friday, March 22, 1996 4:00 p.m. Dr. Oleg A. Sapozhnikov Department of Acoustics Physics Faculty Moscow State University Moscow, Russia Propagating in an absorbing medium, acoustic waves lose not only energy, but also momentum. The latter effect is associated with acoustic radiation pressure. In liquids it gives rise to acoustic streaming. In solids the result…
Effects of Frequency Dependent Absorption on the Propagation and Attenuation of High Intensity Acoustic Waves Containing Shocks
Tuesday, March 19, 1996 4:00 p.m. Dr. Vera A. Khokhlova Department of Acoustics Physics Faculty Moscow State University Moscow, Russia Shock waves used in medicine and other applications of intense ultrasound are greatly influenced by the thermoviscous losses in the propagation medium. The effect of the frequency dependence of the absorption and dispersion coefficient on…