The sound of a bullet hitting a target is sometimes discernable in an audio recording of a shooting event and can be used to determine the distance from shooter to target. This paper provides an example where the microphone is adjacent to the shooter and presents the simple mathematics needed in cases where the microphone is adjacent to the target. Spectrograms of the sound of bullet impact on ...

Modal decays and modal power distribution in acoustic environments are key factors deciding the perceptual quality performance accuracy of audio applications. This paper presents application eigenbeam spatial correlation method estimating time-frequency-dependent directional reflection powers decay times. The experimental results evaluate proposed technique for two rooms with distinct using the...

San Felipe Jalapa de D ⁄ ıaz (Jalapa) Mazatec is unusual in possessing a three-way phonation contrast and three-way level tone contrast independent of phonation. This study investigates the acoustics of how phonation and tone interact in this language, and how such interactions are maintained across variables like speaker sex, vowel timecourse, and presence of aspiration in the onset. Using a l...

Three experiments addressed the hypothesis that production factors constrain phonotactic learning in adult English speakers, and that this constraint gives rise to a markedness effect on learning. In Experiment 1, an acoustic measure was used to assess consonant–consonant coarticulation in naturally produced nonwords, which were then used as stimuli in a phonotactic learning experiment. Results...

The decline of bats demands more widespread monitoring of populations for conservation and management. Current censusing methods are either prone to bias or require costly equipment. Here, we report a new method using passive acoustics to determine bat count census from overall acoustic amplitude of the emerging bat stream. We recorded the video and audio of an emerging colony of Mexican free-t...

Bees play an important role in agriculture and ecology, their pollination efficiency is essential to the economic profitability of farms. The drastic decrease bee populations witnessed over last decade has attracted great attention automated remote beehive monitoring research, with acoustics analysis emerging as a prominent field. In this paper, we review existing literature on report articles ...

1 Robert O. Lawton Distinguished Professor, Department of Mathematics, Fellow AIAA. 2 Post-Doctoral Research Associate, Department of Mathematics. 3 Research Scientist, Structural Acoustics Branch, Aerodynamics, Aerothermodynamics and Acoustics Competency, Member AIAA. 4 Senior Research Scientist, Computational Modeling and Simulation Branch, Aerodynamics, Aerothermodynamics and Acoustics Compe...

Imagine that you are blindfolded inside an unknown room. You snap your fingers and listen to the room's response. Can you hear the shape of the room? Some people can do it naturally, but can we design computer algorithms that hear rooms? We show how to compute the shape of a convex polyhedral room from its response to a known sound, recorded by a few microphones. Geometric relationships between...

Inter-speaker variability is pervasive in speech, and the ability to predict sources of inter-speaker variability from acoustics can afford scientific and technological advantages. An important source of this variability is vocal tract morphology. This work proposes a statistical model-based approach to classifying the shape of the hard palate and the pharyngeal wall from speech audio. We used ...