Woodbury, New York, April 12, 1996
The Acoustical Society of America (ASA) will hold its 131st Meeting May 13-17, 1996 at the Hyatt Regency Indianapolis Hotel in Indianapolis, IN. At the meeting over 680 papers will be delivered. With nearly 7000 members, the ASA is the largest scientific organization in the United States devoted to acoustics.
Acoustic Communication by Ants MRI-Guided Ultrasound Surgery Speech Identifiers for Drunk Drivers and Cold Sufferers Acoustic Pyrometry The Acoustics of Surf Waves Safety of Lithotripsy Pitch, Periodicity, and the Brain Hummingbird Dialects Musical Illusions Assessing the Quality of Musical Reeds Determining the Number of Concurrent Speakers Directivity of Musical Instruments The Inner Ear Synthesizing Automobile Engine Sounds Improving Acoustics at the Great Hall
Ants are thought to communicate primarily through chemicals called pheromones. However, ants also possess anatomical apparatus for producing sounds. Robert Hickling of the University of Mississippi (hickling@sparc.ncpa.olemiss.edu) and his colleagues will report evidence for meaningful acoustic communication in certain kinds of fire ants. The researchers recorded signals that are believed to correspond to distress and attack in addition to an "all's well" signal.
Combining magnetic resonance imaging (MRI) and ultrasound therapy, some researchers believe, may prove to be an excellent approach for certain types of soft-tissue surgery. MRI pictures taken before surgery can help ultrasound beams to be accurately aimed at the target region. During the operation, MRI sequences can provide data on the temperature of the area under surgery and deliver information which can be used to modify ultrasound intensity. Post-surgery MRI pictures can show changes in tissue induced by the ultrasound. Kullervo Hynynen of Harvard Medical School (617-278-0606) will describe in vivo experiments demonstrating this approach. (Paper 3aPAa1)
Drunk drivers may have a new reason to exercise their right to remain silent when arrested. Kathleen Cummings of Georgia Tech (kate@eedsp.gatech.edu) and her colleagues describe efforts to identify quantitative differences in the vocal characteristics of persons in intoxicated and sober states. (4aSC21) These differences may help law enforcement authorities to obtain evidence of intoxication by recording the voices of drunk drivers and subjecting their speech patterns to computer analysis. Renetta Tull of Northwestern (708-467-1949) and coworkers will describe differences that arise in speech recorded by persons before, during, and after bouts of the common cold. One potential application of this research is to improve the performance of automatic speaker recognition systems when used by persons with colds. (4aSC20)
Acoustic instruments are being developed for monitoring the operation of boilers and furnaces. This approach, known as "acoustic pyrometry," is now being used widely to predict furnace overheating and burner malfunctions before these complications occur. As John Kleppe of the University of Nevada (kleppe@moriah.ee.unr.edu) will explain, acoustic pyrometry techniques can determine the volume of gas flow in boilers and furnaces and measure the temperatures of gases in these systems. (4aEA5)
Wave-breaking is thought to be the dominant source of nonbiological noise in the ocean. In the deep ocean, wave breaking is intermittent, but in offshore waters, every appreciably sized wave breaks before it reaches land. At session 1pAO, Nicholas Makris of the Naval Research Laboratory (makris@abyss.nrl.navy.mil), W. Kendall Melville of UC-San Diego (kmelville@ucsd.edu), and others will describe how the sounds of breaking waves can offer information on ocean and geophysical properties such as energy dissipation, the formation of bubbles, and the suspension of sediment.
A topic of much discussion has been the safety of extracorporeal shock wave lithotripsy (ESWL), a technique in which externally generated shock waves are sent through the body to break up kidney stones. There is evidence that ESWL can cause several types of damage to the kidney. In attempts to make this technique safer, Richard Meltzer of Rochester (dick_meltzer@medicine.rochester.edu), and Andrew Evan of Indiana University (evan@anatomy.iupui.edu) and others at sessions 3aPAa and 3pPA present the latest studies on the bioeffects of lithotripsy.
Pitch is the building block of musical melodies and harmonies. The ability to perceive pitch, according to William Hartmann of Michigan State University (hartmann@msupa.pa.msu.edu), is "the most precise of all our human senses." Hartmann will describe how experimental studies on pitch perception are being used to test models on the auditory processing of pitch. He will describe the role of pitch in separating overlapping voices and artificial intelligence models of this phenomenon. (1eID1)
Male hummingbirds sing songs to attract mates. Certain types of hummingbirds establish territorial sites, known as leks, where they carry out this task. Hummingbirds on the same lek cooperate with each other, singing the same song. Hummingbirds at different leks sing different songs, resulting in "dialects" that vary from lek to lek. Sandra L. Gaunt of Ohio State (gaunt.2@osu.edu) explores the hummingbird song and its role in the lek mating system. (4aAB1)
Combining pairs of special computer-generated tones and playing them in a certain sequence can result in a musical illusion in which the tones seem to be either rising or descending endlessly in pitch. Curiously, some people will hear a given sequence as rising while others will hear the same sequence as descending. Diana Deutsch of UC-San Diego (ddeutsch@ucsd.edu) has found that a mother and her children will hear these tones in strikingly similar ways, and that perception of the tones correlates with where the listener grew up. (2pMUb7)
Found in the mouthpieces of musical instruments such as clarinets and saxophones, reeds are essential to generating and manipulating tones in these instruments but can be notoriously uneven in quality. Professionals can spend upwards of $2500 per year on reeds and even then perform using a relatively small fraction of them. Even highly experienced performers cannot assess reed quality through visual inspection. James Payne of Ohio State (614-292-6571) will describe a new technique, known as computerized light transmission analysis, which has been designed to measure reed quality. (2aMU4)
Makio Kashino of NTT Basic Research Labs in Japan (kashino@av-hp.ntt.jp) explores the ability of listeners to judge the total number of people speaking at the same time. Listeners made nearly perfect judges for recordings of up to two talkers, but the accuracy of their responses sharply deteriorated for three or more speakers. Often, the number of speakers was underestimated by listeners. Factors that promoted sound source separation (forward versus reverse speech, and single versus multiple loudspeakers) did not improve performance. (5pPP8)
Musical instruments do not necessarily radiate their sounds the same way in every direction of space. In fact, directivity can be one of the distinguishing features of an instrument. Daniel Martin, editor-in-chief of the ASA (513-231-5278), will describe directional effects in orchestral trumpet, French horn, piano, and organ pipes (3aAA1) and Peter Hoekje of the University of Northern Iowa (plhoekje@uni.edu) will describe studies on wind instruments (3aAA4). The University of Michigan's Gabriel Weinreich (weinreich@mail.physics.lsa.umich.edu) speculates that changes in the directional patterns of violins can account for the "flashing brilliance" of those instruments (3aAA5). A live orchestra will demonstrate these effects. (3pAA1)
In addition to detecting sound, the ear produces a little bit of sound itself. Known as otoacoustic emissions, these sounds are produced in the cochlea or inner ear. Glenis Long of Purdue University (long@physics.purdue.edu) describes the possibility that otoacoustic emisssions can be used to probe the function of the cochlea. (5aPP3) Session 4pSC (contact David Pisoni at Indiana University, pisoni@indiana.edu) is devoted to the advances and successes of cochlear implants in hearing-impaired children.
According to automobile marketers, car purchasers have preconceived expectations of how the engines of different types of cars (luxury, sportscar, compact) should sound. Applying speech synthesis techniques which mimic human voices based on the anatomy of the vocal cords, Scott Amman of Ford Motor Company (usfmczaw@ibmmail.edu) and coworkers are attempting to design computer models that reproduce the sounds of an automobile based on its engine design. This could potentially lead to the design of cars with customized engine sounds. (2aEA6)
One of the most historically renowned auditoriums in New York City, the Great Hall at Cooper Union, has featured speeches from figures ranging from Abraham Lincoln to Bill Clinton. However, this auditorium has suffered perennially from excessive reverberation, resulting in often unintelligible speech. For the past few years, the acoustical properties of the hall have been carefully studied. Now, Gregory Miller of Cooper Union (miller3@cooper.edu) and his colleagues have come up with a simple idea that they believe can significantly reduce reverberation effects while maintaining the architectural integrity of the auditorium. Their idea is to replaster the walls and ceiling with a lower-density, more porous material. (4aAA7)
Meeting abstracts may be viewed at the location http://asa.aip.org/abstracts.html for those with access to the Web.
For more information during the meeting, contact Elaine Moran (elaine@aip.org) at the ASA registration desk, 317-632-1234. For information before the meeting, contact Ben Stein at bstein@aip.acp.org or 301-209-3091. Return to 131st Meeting Archive Return to ASA Press Room