bluuebunny/crossref_metadata_2025 huggingface dataset:
Sound and biological models.
Authors: Porter Michael B. , Houser Dorian S. , Mountain David C. , Siderius Martin
Published: July 2011

We consider the coupling of biological and acoustic models in the ocean (marine bioacoustics). A casual look at journal publications and meeting programs over the last 10 years shows the extraordinary growth in research. Consider these five examples: animats, which are virtual marine mammals, swim in simulated oceans, acting as acoustic dosimeters to simulate the exposure of real animals in the ocean. The animats themselves respond to the sound field, avoiding unpleasant noises or seeking out sounds that suggest feeding or reproductive opportunities. Meanwhile, the songs, whistles, clicks, rumbles, etc., of living mammals allow a listener to follow their paths, or even to coarsely image the ocean environment. As they move through the sound field they may also disrupt it, scattering energy. Thus we see an intimate coupling between the biological models and the sound field in both virtual and real worlds. This talk will present examples of each of these couplings.
Shallow-water acoustic studies with regional ocean models.
Authors: Duda Timothy F. , Lin Ying-Tsong , Zhang Weifeng Gordon , Ponte Aurelian L. , Cornuelle Bruce D. , Lermusiaux Pierre F. J.
Published: July 2011

The value of acoustic propagation modeling using water-column sound-speed fields from computational physical oceanographic models is well established. With a proper investment in measurements and models it is now possible to make predictions of real-time and future acoustic effects of mesoscale eddies and other structures. This capability depends on properly incorporating data from satellite and in situ instruments into data-assimilative models. Many challenges remain, however. First, mesoscale feature uncertainties are high when data are scarce. Second, models do not fully handle gravity waves (internal and surface) and submesoscale features. The present utility of models is high despite these remaining challenges. For example, models running open-loop or with partial boundary condition and internal constraints will generate realistic fields for acoustics studies that have goals other than sound-field prediction. Recent analyzes of the sound propagation effects, at 50–1000 Hz, of internal waves, fronts, and canyons show that realism can improve studies of transmission loss uncertainty and fluctuation characteristics. As examples, internal-wave curvature affects acoustic beam generation and horizontal interference patterns, and internal-tide amplitude and direction affect shallow-water acoustic mode wavenumbers and attenuation parameters. Acoustic fluctuation effects computed with three-dimensional (3D) acoustic modeling through internal-wave permitting ocean models will be presented.
Correlating depth-integrated acoustic intensity fluctuations with observed oceanographic events during the Shallow Water 2006 experiment.
Authors: Sagers Jason D. , Knobles David P.
Published: July 2011

During the Shallow Water 2006 experiment, a 224 Hz moored source located on the New Jersey shelf broadcast 7.5 min transmissions every half hour over several weeks. These transmissions were recorded on three vertical line arrays (VLAs) located between 22 and 34 km seaward of the source. The depth-integrated intensity on each VLA is described as a function of time and VLA position. The observed intensity fluctuations (and statistics) and their correlation with temporally and spatially dependent oceanographic events, such as solitons, soliton packets, diffuse internal wave fields, and Tropical Storm Ernesto, will be presented. The intensity fluctuations are examined primarily in terms of 2-D acoustic coupled-mode theory. Seabed attenuation is likely the primary loss mechanism, and it may be possible to use the observed intensity fluctuations to infer information about seabed properties (such as sound speed ratio and attenuation). [Work supported by ONR]
Evolving mesoscale structure of two-dimensional sonic layer depth based on multisatellite altimetry and ARGO float profiles.
Authors: Menezes Viviane , Vianna Marcio
Published: July 2011

The influence of upper ocean warm core rings (WCRs) on long-range low-frequency sound propagation is well-known in ocean acoustics, through modeling the effects of sonic depth changes in ray paths and wave scattering. The predictions of any range-dependent acoustic detection model applied to a realistic upper-layer ocean acoustic scenario is strongly dependent on characterization of evolving mesoscale and submesoscale features. Since mesoscale dynamics is not directly predictable from climatology, we describe for the South Atlantic a method that statistically relate ARGO-float subsurface profile positions and derived sonic depths with altimetric and geodetic data objectively mapped in high resolution by an improved fast Gauss transform algorithm. The advantage of the method is that it permits us to go one-step ahead in the practical near-real-time prediction of the horizontal structure that can be quickly modeled to serve as input into the chosen acoustic match-field model, tested against the control model without the WCR complexity. Results from a few experiments are described.
Frequency and angular (vertical and azimuthal) characteristics of reverberation of low-frequency tonal signals (200–300 Hz) in shallow water due to wind waves.
Authors: Salin Boris M. , Salin Mikhail B. , Spindel Robert C.
Published: July 2011

This presentation considers the main schemes of calculating the frequency and angular characteristics of reverberation of low-frequency cw signals in shallow water caused by scattering from a rough, wind-driven surface. Experimental and calculated data are given in order to display directivity patterns and levels of the reverberation signals in both vertical and horizontal planes and to display it as a function of the water depth, the propagation path length, the carrier frequency, and the surface roughness spectrum. We note the horizontal angular asymmetry of the scattered side lobes. [B.M.S. and M.B.S. gratefully acknowledge the generous support of the U.S. Office of Naval Research, ONRG.]
The use of pressure dependent subharmonic resonance to increase the signal to noise ratio of ultrasound contrast agent imaging.
Authors: Jafari Sojahrood Amin , Kolios Michael
Published: July 2011

Conventional methods of subharmonic (SH) imaging of ultrasound contrast agents (UCAs) employ a frequency which is approximately twice the resonance frequency of the UCA (the SH resonance frequency). However, this approach may be limited by a low signal to noise ratio. To address this problem, the Hoff model was solved for several UCAs and the SH resonance frequencies of the bubble were calculated for different applied pressures (PAs). By increasing the PA above the pressure threshold for SH generation, the SH resonance frequency shifts toward lower values. Calculation of the scattered pressure in the regime of stable oscillations show that, if the bubble is sonicated with its pressure dependent SH resonance frequencies, the backscattered signal can be significantly stronger than when sonicating with the conventional SH resonance frequency (although the initiation of the SH occurs at a higher PA). The enhancement of the SH and ultraharmonic amplitudes can be up to 7 and 14 dB, respectively. This enhancement may lead to better UCA SH imaging, especially for molecular based imaging protocols.
Investigation of microbubble response to long ultrasonic pulses used in therapeutic applications.
Authors: Mannaris Christophoros , Averkiou Michalakis A.
Published: July 2011

In current drug delivery approaches, microbubbles and drugs can be co-administered intravenously while high intensity ultrasound is applied. The exact mechanisms of microbubble interactions with ultrasound the drug and the cells are not fully understood and sometimes, the optimal ultrasound parameters are simply a case of trial and error. A better understanding of microbubble response to long ultrasonic pulses is important for drug delivery. Two different in-vitro setups to examine the response of microbubbles are presented: with the microbubbles suspended in a large enclosure and with the microbubbles flowing in a capillary. Various commercially available and drug delivery specific bubbles were considered. Acoustic streaming, which greatly influences the observed response from bubbles, was observed in many “typical” drug delivery conditions in the large enclosure setup. With the capillary setup, streaming was eliminated and accurate bubble responses were recorded. In the capillary setup and at high pressures where bubble destruction is prominent, all bubble activity disappears within 80–100 cycles despite the length of the excitation pulse, mainly due to diffusion phenomena. A question is raised whether the enhanced drug delivery seen with longer ultrasound pulses at high pressures is related to the microbubble response or whether other factors are involved.
Estimating concentration of ultrasound contrast agents with backscatter coefficients.
Authors: Leithem Scott M. , O’Brien William D. , Oelze Michael L.
Published: July 2011

Ultrasound contrast agents (UCAs) are used clinically to enhance the contrast of ultrasound images. Recently, microbubbles have been explored as a means to enhance therapeutic techniques. Because the effectiveness of these techniques relies on the UCA concentration at a target site, it would be beneficial to acquire real-time estimates non-invasively. A method for measuring concentration, based upon backscatter coefficients (BSCs) at frequencies above resonance, was developed. Calculation of the BSC was accomplished using plane reference measurements from the back wall of a Plexiglas chamber. For each trial, an average of 500 snapshots of ultrasonic backscatter from Definity microbubbles flowing through the chamber was acquired. Immediately following this procedure, a sample of the UCAs was extracted from the flow path in order to optically verify the concentration estimates. Using measurements of attenuation coefficient through the bubble cloud, BSC was calculated for the 15–25 MHz range. UCA concentration was estimated by using a Levenberg–Marquardt fitting algorithm to match the experimental BSC to a linear scattering model. All BSC-based estimates were within one standard deviation of optically derived estimates. These results indicate that the BSC can be used to measure UCA concentration. [This work was supported by NIH Grant No. R37EB002641.]
Ultrasound-induced angiogenesis requires contrast agent collapse.
Authors: Johnson Chenara A. , O’Brien William D.
Published: July 2011

Ultrasound (US) and ultrasound contrast agents (UCA) ability to induce a particular bioeffect, angiogenesis, has been explored as a means of restoring blood flow to ischemic muscle. Determining the mechanistic motivation of the angiogenic response (AR) is integral to the evaluation of bioeffects, US therapy development, and understanding the physical process. Using a 1 MHz transducer (PRF = 10 Hz, PD = 10 μs), this study explored the effects of oscillation and collapse cavitation (CC) on both acute bioeffects (day 0) and subsequent AR (day 5) in the gracilis muscle of Sprague Dawley rats (N = 20). The UCA used, Definity, was determined, in separate experiments, to have a collapse threshold of approximately 0.25 MPa. Because UCAs demonstrate an increasing percentage of CC with increasing US pressure, this study used pressures ranging from 0 to 0.9 MPa. The acute bioeffects were measured via permeability assessments with Evans Blue Dye. ARs were assessed by vascular endothelial growth factor expression. Capillary density was determined by CD31 staining for both time points. The findings support that CC is necessary to elicit an AR and suggest that acute effects could potentially be used to gauge the AR. [Work Supported by F31 HL097653 (C.A.J.) and R37EB002641.]
Passive cavitation imaging of echogenic liposomes insonified with 6 MHz pulsed Doppler ultrasound in a flow phantom.
Authors: Haworth Kevin J. , Mast T. Douglas , Radhakrishnan Kirthi , Kopechek Jonathan A. , Burgess Mark T. , Huang Shaoling , McPherson David D. , Holland Christy K.
Published: July 2011

Microbubble activity has been linked to bioeffects in a variety of therapeutic ultrasound applications including thermal ablation and localized drug delivery. Passive cavitation imaging of microbubble activity has been demonstrated in vitro during continuous-wave ultrasound exposure [Salgaonkar et al. (2009), JASA 126, 3071–3083; Gyongy and Coussios 2010, IEEE Trans BME 57, 48–56]. Here, we perform passive cavitation imaging of echogenic liposomes (ELIPs) in a flow phantom exposed to 6 MHz pulsed Doppler ultrasound (3.1 μs pulse duration, 1250 Hz pulse repetition frequency) transmitted from a diagnostic scanner (Philips HDI 5000, CL15-7 transducer). Frames of received ultrasound signal were obtained passively on 64 parallel channels recording for 112 μs (L8-3 transducer, Zonare z.one ultra scanner). Received echoes were beamformed by frequency-domain phase shifts to produce cavitation images. Localization of cavitation activity was tested by moving the Doppler exposure volume to three different positions and observing a concurrent spatial shift in cavitation activity. At the highest insonation pressures a loss in echogenicity was observed. Cavitation activity coincided spatially with this loss. Subharmonic and broadband cavitation images for multiple insonation pressures were consistent with previously determined stable and inertial cavitation thresholds for ELIP. [Work supported in part by NIH grants F32HL104916, R01HL074002, R21EB008483, R01HL059586, and R01NS047603.]
Laser sensing techniques for acoustic detection of buried mines.
Authors: Aranchuk Vyacheslav , Sabatier James M. , Burgett Richard
Published: July 2011

Acoustic detection of buried mines is based on excitation of vibrations in the ground with airborne sound and measuring vibration of the ground surface by using a laser interferometric sensor. The principle of detection uses the fact that buried mines have mechanical impedances that are smaller than that of soils. That makes the soil above a mine vibrating with magnitude higher than the surrounding soil. A laser sensor creates a vibration image of the ground by measuring vibration in many points on the surface. The presence of a buried mine can be detected by an abnormality in the vibration image. The method has shown excellent performance in field tests. One limiting factor of the method is a long measurement time due to low frequency of vibrations. Different laser interferometric techniques have been investigated to reduce the time of detection. The paper discusses application of single-beam scanning laser Doppler vibrometry (LDV), multiple-beam LDV, and speckle-interferometry based methods for acoustic detection of mines.
Development of a portable system for acoustical reconstruction of tunnel and cave geometries.
Authors: Bowen David L.
Published: July 2011

Noninvasive remote determination of the geometry of caves, tunnels, and piping complexes has value for both military and commercial activities. Troops that must enter caves, tunnels, or urban storm sewer piping systems, for example, would be greatly aided by first knowing the distance to the next turn, opening, branch, or closure. A system employing a sound source and a pair of acoustic sensors was developed to do this, based on the medical techniques of acoustic laryngometry and rhinometry, and has been demonstrated both in laboratory and in full-scale field situations. Acoustical reflectometry techniques are first used to compute an area versus distance profile of the passageway under interrogation. Other procedures are then used to classify and characterize the various types of “junctions” that could give rise to the observed changes in area (branching versus a simple area expansion, etc.). Results obtained using a prototype field system in full-scale tests indicate that small arms fire can be used in place of a loudspeaker as the sound source (with hydrophones as the sensing elements), thus increasing the portability of the system. Other techniques for remote geometry mapping of tunnel-like spaces will also be discussed. [Work supported by the U.S. Army Corps of Engineers.]
Rayleigh wave technique for underground explorations.
Authors: Lu Zhiqu , Wilson Glenn , Zhang Tianyu
Published: July 2011

A laser Doppler vibrometer (LDV) based multi-channel analysis of surface wave (MASW) method has recently been developed. In the method, an electro-mechanical shaker was used as a seismic source operating in a frequency sweeping mode to excite Rayleigh waves propagating through the soil surface. The surface vibrations along a straight line were detected by a moving LDV. Unlike conventional MASWs that explore soil profile from a few meters to a few tens of meters below the ground, the present MASW investigates underground depth from a few centimeters to a few meters due to its high frequency excitation and high spatial resolution of moving LDV. Two approaches will be used to create two-dimensional (2D) image of subsurface features: dynamic moveout and dispersive curve inversion. The geological anomalies can be identified from the contrasts of the 2D image. Some details and cases will be addressed.
Advances in acoustic communication and navigation transducers for small underwater vehicles.
Authors: Brown David A.
Published: July 2011

The application of piezoceramic (PZT) and single crystal (PMN-PT) transducers for underwater acoustic communication modems and navigation systems is reviewed. Many applications demand increased acoustic bandwidth, moderate to high acoustic power, compact form factors, and in some cases directionality. The presentation reviews Lagrangian based analytical modeling methods and the development of a MATLAB based users-tool kit for virtual prototyping. Experimental results and field testing of many devices are summarized including single crystal fully active segmented modem transducers with measured coupling factors of 0.87 having usable fractional bandwidth of greater than 100%. Several transducers for navigation aids are presentment including pressure gradient multimode, baffled cylinders and spheres, compact arrays, and spiral-wavefront transducers. Examples of the influence of the vehicle body on transducer performance are considered in an experimental investigation of a Webb sea glider with a BTech WHOI-micromodem transducer and hull and wing mounted sensors for trawler avoidance. [Work supported by the ONR.]
Modem-based aids for underwater navigation.
Authors: Green Dale , McManus Steve
Published: July 2011

Both autonomous and semi-autonomous underwater platforms require navigation capabilities. Acoustics have long been the preferred method because all other methods are so limited in range and/or are so costly. Traditional methods have relied on tonal-based waveforms used with any of three approaches: long baseline (LBL), short baseline, or ultra-short baseline (USBL). These systems can be highly effective when propagation conditions are “good” but may incur high cost in terms of false and missed detections. The use of wide-band waveforms can substantially improve performance, but a significant cost is incurred in the complexity required at the receiver. However, given this complexity, consideration should be given to the use of underwater acoustic communications (acomms) as the provider of enhanced navigation aids. We describe three modem-based navigation aids based, two of which have never exhibited a false alarm, and each of which provides substantial improvement over tonal-based systems. We describe a spread spectrum signaling method used in LBL navigation, an underwater GPS system in which any number of platforms can obtain accurate geoposition in a completely passive sense, and we describe a physically small, wide-band modification to conventional USBL. All of these systems provide high accuracy navigation while retaining full acomms links.
System level tradeoffs for broadband transduction in unmanned underwater vehicle applications.
Authors: Thompson Stephen C. , Meyer Richard J. , Beinert Eric M. , Montgomery Thomas C.
Published: July 2011

Unmanned underwater vehicle (UUV) applications, with their inherently severe constraints on size, weight, and power consumption, are being asked to perform acoustic tasks that might previously have been accomodated shipboard. When an acoustic system needs a projector with more than an octave bandwidth at moderate or higher power with a high total system efficiency, there is a dearth of options available. In fact, there are no well established figures of merit for rating transducers in this operating regime, as those appropriate for conventional systems generally assume a single degree of freedom system operating near reasonance. This paper will discuss the many dimensions of this issue.
Science news in the 21st century.
Authors: Powell Devin C.
Published: July 2011

Open a newspaper in 1980s, and youward likely find a science section. Open one in 2011, and you may not even find a science reporter. With the rise of the Internet and the decline of print, the news world is changing. Science journalism is increasingly relegated to pages of specialty publications. American science literacy remains poor. And the NSF is pushing scientists to make a greater effort to reach out to the public. The presenter will draw upon his experiences as a science reporter to illustrate and describe the state of science journalism, what the American public knows about science, and your place as an acoustic researcher in this ever-changing landscape.
A veteran reporter’s perspective on science.
Authors: Boyle Alan
Published: July 2011

As MSNBC.com’s science editor, Alan Boyle runs a virtual curiosity shop of the physical sciences and space exploration, plus paleontology, archaeology, and other ologies that strike his fancy. During his 34 years of daily journalism in Cincinnati, Spokane and Seattle, he survived a hurricane, a volcanic eruption, a total solar eclipse, and an earthquake. Join Boyle for an insider’s take on the mind of the reporter—how journalists approach complex scientific topics and complex scientists, and what information they are looking for.
Finding my voice: My expericences communicating research with the media.
Authors: Benoit-Bird Kelly
Published: July 2011

Talking with the media can be intimidating but it can also provide a great platform for reaching the public, increasing the impact of your research. Recently, I have had the opportunity to interact with television, radio, magazine, and newspaper outlets about my work. These experiences have ranged from frustrating to inspiring. So, how do you make sure that coverage of your work is at least accurate and hopefully engaging for all concerned? First, do not be afraid to ask for help. If your institution has an outreach, communications, or press office, talk with them before the need to interact with the press comes up and each time you are contacted by the media. Second, before agreeing to an interview, be sure you know who you are talking to. Determine what the focus of the story they are working on is, if the interviewer has an agenda, and why they have chosen to talk to you. Third, prepare your key messages in advance and repeat them often during the interview. These messages should be clear and concise so they are easy to quote or turn into sound bites. Finally, practice saying what you want heard and answering questions.
The cold call: How to face an interview.
Authors: Boyle Alan
Published: July 2011

Talking to a reporter can be an exciting or a harrowing experience. In the second part of his talk, veteran science reporter Alan Boyle will conduct a mock interview of scientist Steven Garrett of the Acoustical Society of America. Watch the 10 min interview unfold to experience firsthand the potential pitfalls and opportunities involved in this experience.
Aluminum handbells for enhanced bass sound.
Authors: Rossing Thomas D.
Published: July 2011

In order to obtain a higher radiation efficiency and thereby enhance the sound of bass bells, the Malmark company makes a bass handbell of aluminum. [Rossing, et al., MRS Bull. 20, 40 (1995)]. These aluminum bells are larger in diameter than the corresponding bronze bells, and they have lower coincidence frequencies, both of which lead to more efficient radiation of bass notes. In addition they are considerably lighter in weight, and thus they are more easily handled by bell ringers.
Soundbox behavior in environments with varying sound speed.
Authors: Waltham Chris , Chen Mo , Kotlicki Andrzej , Wolfe Nathan , Yu Jing Fei , Zhu Chengchong
Published: July 2011

The radiation produced by the wooden soundbox of a string instrument is largely the result of the coupling of oscillations in the wood and those of the enclosed air. The traditional way of studying this interaction is to make modifications to the instrument such as adding masses to the soundboard and chimneys to the soundhole. Presented here is an alternative approach that changes the sound speed of the environment using a tent filled with different gases. The resulting admittance data, expressed as contour plots, show clearly the relationship between air and wood modes. The effect of these modes on the radiation of the instrument is demonstrated by measurements of monopole radiativity for a guitar (with and without the hole blocked) and these data are compared to the output of a simple model. Other instruments studied with the gas tent include violins (regular and balsa), viola, setar, and sound.
Designing soundboards with flexural disk models.
Authors: Davis Evan B.
Published: July 2011

Musical instruments are designed to be efficient sound radiators that can survive the rigors of the handling and use by musicians. A flexural disk soundboard and ported box system is developed to explore various structural acoustic design strategies. The flexural disk is used to link the structural and acoustic properties of the soundboard. Musical instruments are designed to reproduce a range of frequencies. The playing frequency range of an instrument is defined as being from the frequency of lowest open string to the frequency an octave above the frequency of the highest open string. The fundamental or main wood mode of a string musical instrument, plucked or bowed, is observed to be at the center of the instrument’s playing range. The main air mode is placed approximately an octave below the main wood mode. Soundboards are sized to be approximately a quarter of the acoustic wavelength in diameter at the main wood frequency. The simple flexural disk models with their linked structural acoustic properties demonstrate a solid structural acoustic logic to the empirically developed instruments and why these designs have been so resistant to change by inventive and creative contemporary instrument makers.
Philosophical viewpoints on noise from wind power projects.
Authors: Duncan Edward C. D.
Published: July 2011

Many people are involved with evaluating, engineering, developing, and opposing wind power projects. While there are many worldviews on global warming, renewable energy, and green technologies, this paper focuses on the philosophical viewpoints surrounding noise from wind power projects. After identifying various stakeholders, the paper investigates how some great historical and current minds have contributed, likely unknowingly, to this field including Gifford Pinchot, John Muir, Jonathan Edwards, Mark Sagoff, Bryan Norton, and Cass Sunstein. A brief review of the history of noise in the rural environment comparing transportation noise with wind turbine noise will be provided. The relation between cost-benefit analysis, the precautionary principle, and wind power noise ordinances will be discussed. The paper will wrap up with some thoughts of what Sagoff may have to offer regarding NIMBYism and why Nortons call for convergence is also a call for acousticians to practice good science.
Audible low-frequency wind turbine sound.
Authors: Richarz Harrison, F. , Richarz Werner G.
Published: July 2011

To date a large fraction of research on wind turbine sound has been directed at the audible spectrum. Rotation of wind turbine blades is a primary cause of the cyclic broad-band sound that is characteristic of wind turbines. Auto-correlations of measured wind turbine sounds exhibit distinct, periodic “low frequency” pulses. The pulse duration is but a fraction of the blade passage period, with energy content of the order of 20–40% of the overall mean square pressure. Analytical decomposition of the low-frequency pulses reveals line spectra whose components diminish relatively slowly. The spectrum levels of the frequency components above 20 Hz are sufficiently high to be audible under favorable ambient conditions. This hypothesis was tested by generating and listening to various possible pressure time histories that share the shape of the low-frequency pulses as measured by auto-correlations. When propagation effects such as scattering are accounted for, the relative phase shifts suffered by the higher frequency components result in an audible swoosh.
A community noise law for wind turbines.
Authors: Schomer Paul
Published: July 2011

The noise generated by wind turbines, termed wind energy conversion systems (WECSs), appears to be a growing problem worldwide. The WECSs seem to be especially a problem in quiet rural areas, areas where there is known to be a greater expectation for peace and quiet than in other areas. This paper presents an ordinance for use in such areas when appropriate vis-à-vis state and/or local laws and regulations. The ordinance includes metrics, criteria, background determination, WECS noise prediction, and enforcement. The ordinance is universally applicable to communities experiencing WECS noise, except for the criteria which are geared toward quiet rural areas, but are easily adjusted to less noise sensitive areas on the basis of the ambient in these areas and on the basis of applicable national and international standards.
Wind turbine noise ordinances: A review of selected state and local regulations.
Authors: Old Isaac H. C. , Eros Emily J. , Duncan Eddie C. D.
Published: July 2011

Noise regulations can often have a great impact on the siting of wind turbines. In the United States, there are no national wind turbine noise regulations. State standards are often not in place, leaving wind turbine siting regulations up to local authorities. This presentation discusses an assortment of both state and local standards from the United States, their implications, and from what basis the ordinances are developed.
Planning for small wind turbines in California.
Authors: Bennett John C.
Published: July 2011

A case study in the development of regulatory noise standards for wind energy projects is presented for a California county. The discussion will focus on small wind turbines, their setbacks for safety and noise effects, acceptable heights, and related installation issues. A summary of possible guidelines and field studies points out the ongoing concerns that exist over this topic in California and the rest of the United States.
Isolation strategies and results in repurposed spaces for theater and music.
Authors: Woolworth David S.
Published: July 2011

Three repurposed buildings are examined with attention to noise isolation approaches and structural issues. Two black box theaters, one inside a brick powerhouse, and a second inside an early 1900s dorm that includes new classrooms, are observed. A third project is an early 1900s music building gutted and redesigned for integrated recording and improved isolation. Additional items of interest in regard to mechanical noise, acoustics, and historical commission limitations are presented.
Auditory-somatosensory integration in the auditory brainstem and its alteration after cochlear damage.
Authors: Shore Susan E.
Published: July 2011

In addition to auditory-nerve inputs, the cochlear nucleus (CN) receives extensive non-auditory inputs from somatosensory ganglia and brainstem nuclei [Shore et al., JCN (2000); Zhou and Shore JCN, (2007)]. The effects of stimulating these pathways on CN physiology are examined using multichannel technology to measure single- and multi-unit activities across populations of neurons in both the dorsal and ventral divisions of the guinea pig CN. Neurons in both CN divisions show evidence of multisensory integration by exhibiting non-linear summation of auditory nerve and somatosensory inputs. Thus, somatosensory neurons can suppress or enhance acoustically evoked response rates as well as altering their temporal patterns. These changes may explain why some patients with tinnitus can modulate the loudness and pitch of their tinnitus by somatic maneuvers of the head and neck. Exploring how these pathways change after various forms of deafness allows us to delve into the realm of neural plasticity, hyperacusis, and tinnitus. Noise induced deafness renders CN neurons more sensitive to somatosensory stimulation as well as increasing the spontaneous rates of those neurons responsive to these inputs [Shore et al., EJN (2008)], findings that can be explained by cross-modal reinnervation [Zeng et al., J. Neurosci. (2009)].
Neuronal mechanisms and perceptual significance of somatoauditory interactions in primate A1.
Authors: Schroeder Charles
Published: July 2011

Recent anatomical, physiological, and neuroimaging findings indicate multisensory convergence at early, putatively unisensory stages of cortical processing. We sought to confirm somatosensory-auditory interaction in AI, and to define both its physiological mechanisms and its consequences for auditory information processing. Laminar current source density and multiunit activity were sampled during multielectrode penetrations of primary auditory area AI in awake macaques revealed clear somato-auditory interactions, with a novel mechanism: Somatosensory inputs appear to reset the phase of ongoing neuronal oscillations, so that accompanying auditory inputs arrive during an ideal, high excitability phase, and produce amplified neuronal responses. In contrast, responses to auditory inputs arriving during the opposing low-excitability phase tend to be suppressed. We speculate that these effects are likely mirrored by corresponding changes in the gain of the perceptual representation. Our findings underscore the instrumental role of neuronal oscillations in sensory operations. The timing and laminar profile of the multisensory interactions in AI indicate that nonspecific thalamic systems may play a key role in the effect.
Pitch and loudness interactions between audition and touch.
Authors: Yau Jeffrey M. , Olenczak J. Bryce , Weber Alison I. , Dammann J. Frank , Bensmaia Sliman J.
Published: July 2011

Sensory signals combine and interact to produce stable representations of our environment. Audition and touch both convey information about environmental oscillations. We hypothesized that the two modalities interact in the perception of sounds and vibrations. We conducted a series of psychophysical experiments to explore how auditory and tactile signals interact in frequency and intensity perception. We found that audio-tactile pitch interactions are bidirectional, as distractors influence frequency perception regardless of the attended modality. In contrast, we found that loudness interactions depend on the attended modality: Tactile distractors influence judgments of auditory loudness, but judgments of tactile intensity are impervious to auditory distractions. We also found that audio-tactile pitch and loudness interactions differ in their sensitivity to stimulus timing. These results reveal that auditory and tactile inputs combine differently depending on the perceptual task. That distinct rules govern the integration of auditory and tactile signals in pitch and loudness perception implies that the two rely on separate neural mechanisms.
The effect of atypical nasal resonance on intelligibility in sentence-length stimuli.
Authors: Watson Peter , Plichta Bartek
Published: July 2011

Kent and Rosenbek [(1989)] hypothesized that abnormally high nasal resonance (HNRS) due to a paretic or paralyzed velopharyngeal mechanism in speakers with dysarthria could worsen intelligibility. Contrastingly, Whitehill’s [(2000)] review of literature found few that believe that HNRS associated with cleft palate contributes very little to a worsening of intelligibility. Determining the effect of atypical nasality on intelligibility is difficult to determine, because HNRS in disordered speech populations is almost always accompanied by other speech/voice abnormalities. A method of synthesizing different degrees of nasal resonance to sentence-length stimuli has been developed and successfully tested for perceptual adequacy. This method was used to synthesize three degrees of nasal resonance (none, mild, and moderate) in 30 sentences spoken by a healthy speaker. The sentences contained only oral phonemes. The sentences were normalized for intensity and mixed with noise and presented to 30 listeners over headphones. The listeners were instructed to orthographically transcribe what they heard. The sentences without nasal resonance were 10%–15% more intelligible than those sentences with increased nasal resonance.
The effect of the frequency of deep-brain stimulation on fine-grained acoustic features of speech.
Authors: Chen Yu-Wen , Watson Peter , Montgomery Erwin B. , Walker Harrison
Published: July 2011

Deep-brain stimulation (DBS) has been used for approximately 1 decade to ameliorate the symptoms of Parkinson's disease (PD). DBS often ameliorates many of the atypical motor symptoms of PD—with the exception of speech production. Clinically significant improvement of speech is not realized or in some cases is worsened [Tornquist et al. (2005). One potential explanation of this paradox is that the DBS settings used to improve limb and truncal control are set for force generation, but not for the complex agonist-antagonist interplay that is required for speech [Montgomery, (2008)]. The data from six patients with PD who have implanted DBS systems will be presented. Each patient produced sustained vowels, sustained fricatives, and oral reading of sentences under four different DBS frequency settings. Data show that for some settings patients were able to increase loudness only, but for other settings loudness is slightly reduced but vowel formant space is increased and spectral kurtosis of fricatives is decreased. The experimenters performing the acoustic analysis were blind to the frequency settings.
Temporal structure in the speech of a person with dementia: A longitudinal case study.
Authors: Carozza Linda , Quinn Margaret , Mack Julia , Bell-Berti Fredericka
Published: July 2011

Cognitive and language processes in dementia have been studied extensively, but motor speech degeneration in the course of dementing illness has been relatively unexplored. The potential for early dissociation of motor functions of language at the level of speech production has not been explored; an interaction between motor speech and language production and perception changes should inform our understanding of the deterioration in dementia. We have previously reported results of a preliminary study of the temporal structure in the speech of persons with dementia. In that study, one of the participants showed inconsistent final lengthening and effects of final consonant voicing on vowel duration, as well as a VOT pattern that suggested a reduced distinction between American English /b/ and /p/. This study explores changes in the temporal structure of speech of that participant, who was recorded 6 months after the first session. He produced a series of short phrases containing a target word occurring in phrase-medial or -final position; the target word began with a fricative or voiced or voiceless stop consonant and ended with /t/ or /d/. We will report on temporal pattern changes in VOT, phrase-final lengthening, and the effect of final consonant voicing on vowel duration.
Relative fundamental frequency as an acoustic correlate of vocal effort in spasmodic dysphonia.
Authors: Stepp Cara E. , Eadie Tanya L.
Published: July 2011

Individuals with vocal hyperfunction have lowered relative fundamental frequency (RFF) in vowels immediately preceding and following a voiceless consonant, but the relationship between RFF and perceived voice quality has yet to be studied in neurogenic voice disorders. The purpose of this study was to determine the relationship between RFF with listeners’ perceptions of 19 individuals with adductor spasmodic dysphonia. Speech recordings were presented to 20 inexperienced listeners who evaluated effort and overall severity using visual analog scales. The correlation coefficient (R2) between average effort and severity measures and an RFF measure was calculated as a function of the number of acoustic instances used for the RFF estimate (1–9, of a total of nine voiced-voiceless-voiced instances). Increases in the number of acoustic instances used for the RFF average led to increases in the correlation with perceptual measures, with use of six or more instances resulting in a stable estimate. Correlation coefficient values were highest between effort and RFF (range R2=0.06–0.43), with slightly lower correlation coefficients between severity and RFF (range R2=0.06–0.35). This study indicates that RFF measures are correlated with perceived voice quality and that guidelines should be developed for calculating reliable estimates of RFF in future research.
Envelope modulation spectrum: Exploring the challenges to intelligibility of dysarthric speech.
Authors: Utianski Rene L. , Lansford Kaitlin , Lotto Andrew , Liss Julie M.
Published: July 2011

This study explores whether information obtained from the envelope modulation spectrum (EMS) can predict the type of intelligibility decrement experienced by listeners of dysarthric speech. Previously, Liss et al. [J. Speech Lang. Hear. Res. 53, 1246–1255 (2010)] demonstrated that spectralinformation obtained via EMS can classify individuals with different patterns of degraded speech into their appropriate clusters. Variables noted as significant in discriminating dysarthria types, such as relative energy above and below the region of 4 Hz, are of particular interest. While the analyzes showed variations of energy in certain octaves of the acoustic signal were critical for this analysis, it is unclear which perceptual components map onto these measures. Using performance measures that capture listeners’ strategies to understand speech at the segmental, suprasegmental, and phonetic levels (intelligibility, lexical boundary errors, and word substitutions), regressions will be performed to determine which information contained within the EMS metrics can account for the variability in listener performance at various levels. Ultimately, this will allow us to look at trends in the EMS output, identify the source of intelligibility decrement, and predict listener performance on outcome measures. Results will bear on models of connected speech perception as well as clinical practice.
Contribution of vowel distinctiveness to intelligibility and vowel identification accuracy of dysarthric speech.
Authors: Lansford Kaitlin L. , Liss Julie M. , Utianski Rene L. , Azuma Tamiko , Dorman Michael F. , Lotto Andrew J.
Published: July 2011

Distorted vowel production is a hallmark characteristic of dysarthric speech and often is characterized by spectral and temporal degradation, flattening of spectral change formants, and vowel space distortions that may differentially affect high versus low or front versus back contrasts. Because acoustic information critical to accurate speech perception is contained in vowels, it is important to ask how such degradations influence the resulting percept. To date, attempts to characterize this relationship have met with mixed results. In the present investigation, a variety vowel space metrics were derived from vowels produced by 48 speakers with dysarthria to assess their ability to predict perceptual outcome measures (e.g., intelligibility and vowel identification accuracy). Novel metrics capturing distinctiveness of spectral neighbors (i.e., dispersion of vowels) were included in this analysis, as recent evidence suggests that vowel distinctiveness, not vowel space area, better predicts vowel intelligibility [Neel, J. Speech Lang. Hear. Res. 51, 574–585 (2008)]. Results of several stepwise multiple regressions support these findings as measures of vowel dispersion both novel and established were included in models that significantly predicted both intelligibility and vowel accuracy. Results of the present analysis provide compelling support of inclusion of such dispersion metrics in the study of dysarthric vowel perception.
Prosodic characteristics of speech directed to adults and to infants with and without hearing loss.
Authors: Dilley Laura C. , Cropsey Evamarie , Kondaurova Maria V. , Bergeson Tonya R.
Published: July 2011

Studies have shown that infant-direct speech (IDS) is distinguished from adult-directed speech (ADS) via a variety of acoustic-prosodic characteristics, including fundamental frequency and rate. However, little is known about how IDS and ADS may be distinguished in terms of linguistically relevant prosodic constructs, such as pitch accents, nor how these constructs map onto acoustic differences previously identified for IDS vs ADS. To investigate these issues, longitudinal recordings of mothers reading a storybook to their typically developing infants and to an experimenter were made when the infants were approximately 3, 6, or 9 months old. Trained analysts used an annotation system to code prosodic characteristics, including rhythmic prominences, pitch accents, and intonation phrase boundaries. Preliminary analyzes of labeled corpora revealed that mothers produced significantly more prominences in IDS than in ADS. In addition, mothers showed substantial individual differences in rates of prominence production in IDS and ADS. Future work will include acoustic analyzes of labeled prosodic constructs, as well as investigations of how prosodic variation in mothers’ speech may predict speech-language outcomes in both normal-hearing children as well as children with hearing loss. [Work supported by NIH-NIDCD Grant No. R01DC008581.]
The intelligibility of clear speech at normal and slow rates for older hearing-impaired listeners.
Authors: Krause Jean C. , Siapno R. Ann , Hansen Ari B.
Published: July 2011

Sentences spoken “clearly” are significantly more intelligible than those spoken “conversationally” for normal-hearing and hearing-impaired listeners in a variety of listening environments [e.g., Payton et al., J. Acoust. Soc. Am. 95, 1581–1592 (1994)]. Typically, clear speech is also spoken more slowly than conversational speech [Picheny et al., J. Speech Hear. Res. 29, 434–446 (1986); Uchanski et al., ibid. 39, 494–509 (1996)]. However, talkers can produce a form of clear speech at normal rates that provides a large intelligibility advantage to young normal-hearing listeners in noise [Krause and Braida, J. Acoust. Soc. Am. 112, 2165–2172 (2002)]. To determine whether this form of clear speech provides a similar benefit to older hearing-impaired (OHI) listeners, this experiment examined the intelligibility of conversational and clear speech at normal and slow rates (conv/normal, clear/normal, conv/slow, and clear/slow) for 11 OHI listeners with symmetric, sloping, moderate SNHL. Although clear speech at normal rates provided only a very small benefit on average, large benefits (comparable to clear/slow speech) were obtained in certain talker/listener combinations. For two of the four talkers, the intelligibility advantage was consistent across listener, suggesting that the benefit of clear speech at normal rates for this population may be talker-dependent.