The Near Pressure Field of Coaxial Subsonic Jets

Friday, January 30, 2009 4:00 p.m. ETC 4.120 Professor Charles E. Tinney Department of Aerospace Engineering and Engineering Mechanics The University of Texas at Austin http://www.ae.utexas.edu The principle focus of this presentation is towards developing a better intuition for the mechanisms by which unbounded turbulent jet flows generate sound. The research was performed as part…

Experimental Studies of Microbubble Dynamics in Ultrasound Using Ultra-High-Speed Imaging and Optical Trapping

Friday, November 21, 2008 4:00 p.m., ETC 4.120 Dr. Valeria Garbin University of Twente The Netherlands pof.tnw.utwente.nl Contrast agent microbubbles are widely used in the field of ultrasound medical imaging to enhance contrast of ultrasound images and quantify organ perfusion, among many other applications. A full understanding of the behavior of these micron-scale bubbles under…

Sensing Resonant Targets through Iterative, Single-Channel Time Reversal

Friday, October 24, 2008 4:00 p.m., ETC 4.120 Zachary J. Waters Department of Mechanical Engineering Boston University http://www.bu.edu/me The presence of noise and coherent returns from clutter often confound efforts to detect and identify targets buried in the ocean. Returns from a buried resonant target are enhanced by using iterative time reversal with a single…

Molecular Specific Photoacoustic Imaging with Gold Nanoparticles

Friday, October 17, 2008 4:00 p.m., ETC 4.120 Srivalleesha Mallidi Department of Biomedical Engineering The University of Texas at Austin http://www.bme.utexas.edu Cancer has become one of the leading causes of death. The early detection of cancer is absolutely necessary to decrease the mortality rate and also to obtain effective therapeutic outcomes. Advances in materials science…

Analog Feedback Control of an Active Sound Transmission Control Module

Friday, September 26, 2008 4:00 p.m., ETC 4.120 Jason D. Sagers Department of Mechanical Engineering Brigham Young University http://www.physics.byu.edu/Research/acoustics An analytical and experimental proof-of-concept is presented for a new feedback-controlled sound transmission control module for use in an active segmented partition (ASP) array. The objective of such a module is to provide high transmission loss…

Review of Drill String Acoustic Telemetry System

Wednesday, September 17, 2008 4:00 p.m., ETC 4.120 Dr. Fernando Garcia-Osuna Schlumberger Sugar Land Integration Center (SPC) Sugar Land, Texas http://www.slb.com and Khalid H. Miah Department of Electrical and Computer Engineering The University of Texas at Austin http://www.ece.utexas.edu Acoustic wireless telemetry systems for logging and measurements while drilling (LWD/MWD) applications, the drill string being the…

Theory and Estimation of Acoustic Intensity and Energy Density

Friday, September 12, 2008 4:00 p.m., ETC 4.120 Derek C. Thomas Department of Physics and Astronomy Brigham Young University http://www.physics.byu.edu/Research/acoustics In order to facilitate the acquisition and accurate interpretation of intensity and energy density data in high-amplitude pressure fields, the expressions for intensity and energy density are examined to ascertain the impact of nonlinear processes…

Laboratory Measurements of the Speed of Sound in Water-Saturated Granular Sediments

Friday, September 5, 2008 4:00 p.m., ETC 4.120 Theodore F. Argo IV Department of Mechanical Engineering and Applied Research Laboratories The University of Texas at Austin http://www.me.utexas.edu A better understanding of sound propagation in water-saturated granular sediments is required for improved shallow-water sonar performance and mine detection. For example, no existing first-principles model has accurately…

Human-Based Percussion Detection and Self-Similarity in Electroacoustic Music

Thursday, June 12, 2008 10:00 a.m. John Anderson Mills III Department of Electrical and Computer Engineering The University of Texas at Austin http://www.ece.utexas.edu Ph.D. Dissertation Defense Electroacoustic music is music that uses electronic technology for the compositional manipulation of sound, and analyzing this music requires special measures.  A preliminary tool set to analyze percussivity and…

Plasmonic and Metamaterial Cloaking: A Route for Acoustic Cloaks?

Wednesday, June 11, 2008 10:00 a.m. in ARL Auditorium Dr. Andrea Alu Department of Electrical and Systems Engineering University of Pennsylvania http://www.seas.upenn.edu/~andreaal/index.html The quest for miniaturizing and optimizing the performance of electromagnetic devices for numerous applications (wireless and optical communications, imaging, …) has fostered in recent years a strong interest in artificial materials, metamaterials and…

The Size and Shape of Intracochlear Pressure

Thursday, May 15, 2008 3:30 p.m. in ACES 6.304 Professor Elizabeth S. Olson Department of Biomedical Engineering and Department of Otolaryngology/Head and Neck Surgery Columbia University http://www.entcolumbia.org Upon sound stimulation, the eardrum and ossicles are set in vibration. The stapes vibration pressurizes the cochlear fluids.  Due to the cochlea’s geometry and its approximately symmetric division…

A Model of the Interaction of Bubbles and Solid Particles under Acoustic Excitation

Friday, April 25, 2008 3:00 p.m. Todd A. Hay Applied Research Laboratories The University of Texas at Austin http://www.arlut.utexas.edu Ph.D. Dissertation Defense Dynamical equations of motion are presented for the interaction of clustered spherical bubbles and solid particles suspended in liquid. Both the bubbles and particles are free to pulsate and translate, and bubble coalescence…

Three-Dimensional Geoacoustic Inversion of the New Jersey Shelf

Friday, April 11, 2008 4:00 p.m. Megan S. Ballard Applied Research Laboratory The Pennsylvania State University http://www.arl.psu.edu Perturbative inversion, based on a linearized relationship between sound speed in the sediment and modal eigenvalues, is applied to data from the Shallow Water Experiment 2006.  Data were collected by towing a low-frequency sound source out and back…

Recording Classical Music as an Exercise in Realistically Capturing an Acoustic Event

Friday, April 4, 2008 4:00 p.m. John Hadden CD Producer and Engineer London, England http://www.johnhadden.com The ultimate goal of a classical music engineer is to record a musical performance as realistically as possible, capturing the very subtle details of sound colors, onset transients and dynamics as well as the reverberation, reflections and diffraction of the…

Micromachined Optical Diffraction-Based Sound and Vibration Sensors

Monday, March 3, 2008 10:00 a.m. Dr. Neal A. Hall Micro-Audio, LLC Atlanta, Georgia 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 of device size and capacitance, creating an unconstrained mechanical and acoustical design…