Investigation of the Cancellation of Acoustic Waves Scattered from an Elastic Sphere

Friday, November 13, 2009 4:00 p.m. in ETC 4.120 Matthew D. Guild Applied Research Laboratories The University of Texas at Austin www.arlut.utexas.edu The topic of acoustical cloaking has gained significant attention in recent years due to the successful creation of electromagnetic cloaks using metamaterials. Two specific approaches have been suggested to successfully construct acoustical cloaks:…

Speech Perception: An Engineer’s View

Friday, November 6, 2009 4:00 p.m. in Burdine 208 Professor Robert I. Damper School of Electronics and Computer Science University of Southampton Southampton, UK www.isis.ecs.soton.ac.uk/areas/?view=speech Human speech is a complex biological and social phenomenon. Historically, in among the morass of complexity, it has not always been clear precisely what is the explanandum (the phenomenon or…

Nonlinear Sound and Sound-Like Wave Interactions in Quantum Liquids

Friday, October 23, 2009 4:00 p.m. in ETC 4.150 Dr. Nellie I. Pushkina Scientific Research Computing Center Moscow State University Moscow, Russia www.srcc.msu.su/nivc/index_engl.htm Quantum liquids present a very good opportunity for studying sound and sound-like wave processes. In these fluids there exist a number of various types of weakly damped excitations not present in classical…

The Songs of Bats and Dissecting the Auditory System

Friday, October 9, 2009 4:00 p.m. in ETC 4.120 Professor George D. Pollak Section of Neurobiology School of Biological Sciences The University of Texas at Austin www.utexas.edu/neuroscience/Neurobiology/GeorgePollak/index.html Bats are best known for their echolocation abilities but they also are among the most colonial of mammals, living in caves with populations that can number in the…

Wave Propagation in Water-Saturated Sand and Grain Contact Physics

Friday, October 2, 2009 4:00 p.m. in ETC 4.120 Dr. Nicholas P. Chotiros and Dr. Marcia J. Isakson Applied Research Laboratories The University of Texas at Austin www.arlut.utexas.edu Measurements in sandy ocean sediments over a broad range of frequencies show that the sound speed dispersion is significantly greater than that predicted by the standard Biot-Stoll…

Cochlear Implants

Friday, September 25, 2009 4:00 p.m. in ETC 4.120 Amy Gensler, M.A., Cert. AVT Austin Ear Clinic Austin, Texas www.austinear.com Cochlear implants are life-changing prosthetic devices that can dramatically improve hearing and speech perception for people with severe-to-profound sensorineural hearing loss. Cochlear implant technology is much improved today compared to technology first commercially released in…

Experimental Investigations of Bubble Dynamics in Constrained Geometries

Friday, September 18, 2009 4:00 p.m. in ETC 4.120 Dr. Todd A. Hay Applied Research Laboratories The University of Texas at Austin www.arlut.utexas.edu The behavior of ultrasound contrast agent (UCA) microbubbles in confining environments is relevant for several biomedical applications including imaging and targeted drug delivery. This talk will focus on experiments and associated modeling…

Model for the Response of Human Lung Tissue to Low-Frequency Underwater Sound

Friday, September 4, 2009 4:00 p.m. in ETC 4.120 Dr. Mark S. Wochner Applied Research Laboratories The University of Texas at Austin www.arlut.utexas.edu The time-dependent nature of mammalian lung damage due to acoustic excitation at the lung’s resonance frequency has been demonstrated by Dalecki and coworkers at The University of Rochester. A finite-element-based model of…

Investigations of Acoustic and Seismic Coupling at the Air-Earth Boundary

Friday, May 29, 2009 10:00 a.m. in the ARL Auditorium Dr. Wheeler Howard Miltec Research and Technology Oxford, Mississippi www.ducommun.com/miltec/mrt Soils overlying naturally occurring hardpans, such as caliche or fragipan, normally experience decreased crop yield and increased erosion rates. Mapping these layers on a field scale would permit the judicious distribution of hydraulic and agricultural…

The Development and Execution of Mate Choice in Túngara Frogs

Friday, April 10, 2009 4:00 p.m. in ETC 4.120 Alexander T. Baugh The Institute for Neuroscience The University of Texas at Austin www.neuroscience.utexas.edu Interest in the question of when and how species recognition and mate preferences emerge in animals with strong species-typical predispositions has faded since the time of the classical ethologists. In its place,…

Modeling of Sonic Tools with hp-Adaptive Finite Elements

Friday, March 13, 2009 4:00 p.m. in ETC 4.150 Professor Leszek F. Demkowicz Department of Aerospace Engineering and Engineering Mechanics Assistant Director, Institute for Computational and Engineering Sciences The University of Texas at Austin www.ices.utexas.edu In finite element modeling, hp-adaptive methods allow for locally varying element size, h, and polynomial order, p, combining the strengths…

Micromachined Optical Diffraction-Based Sound and Vibration Sensors

Friday, February 27, 2009 4:00 p.m. in ETC 4.120 Professor Neal A. Hall Department of Electrical and Computer Engineering The University of Texas at Austin www.ece.utexas.edu This presentation will summarize recent developments with micromachined microphones employing diffraction-based optical displacement detection. The approach has the advantage of providing high-displacement detection resolution of the microphone diaphragm, independent…

Parametric Array: A Novel Application of Nonlinear Acoustics

Friday, February 20, 2009 4:00 p.m. RLM 7.104 Professor David T. Blackstock Department of Mechanical Engineering and Applied Research Laboratories The University of Texas at Austin http://www.me.utexas.edu When two intense primary sounds of different frequencies propagate together, their nonlinear interaction produces various distortion components. Particularly interesting is the difference frequency component, which is at the…

Why Make Complex Acoustic Signals that Attract Predators? The Dynamics of Túngara Frog Signal Complexity

Friday, February 13, 2009 4:00 p.m., ETC 4.120 Karin L. Akre and Professor Michael J. Ryan Section of Integrative Biology The University of Texas at Austin http://www.biosci.utexas.edu/ib Female túngara frogs (Physalaemus pustulosus) use male acoustic signals to make mate choice decisions. Males produce advertisement calls of variable complexity. They produce frequency-modulated vocalizations, called whines, and…

High-Frequency Ultrasound Transducers and Applications

Wednesday, February 4, 2009 4:00 p.m. BME 3.204 Dr. Jeffrey A. Ketterling Riverside Research Institute New York, New York http://www.rri-usa.org/biomed.php This seminar will focus on recent work involving high-frequency ultrasound (HFU) transducers (>20 MHz) that are widely used for fine-resolution ophthalmic and small-animal imaging. Most HFU imaging is now performed with single-element, focused transducers. These…