bluuebunny/crossref_metadata_2025 huggingface dataset:
On the interaction of tone and intonation in Mandarin Chinese
Authors: Shih Chilin
Published: October 2005

Intonation in many languages, including English, is realized most effectively by changes in fundamental frequency. It is important to investigate whether this relation holds true in a tone language, where F0 variation may affect lexical meaning. This paper reports the interaction of tones and intonation in a tone language, Mandarin Chinese, and calculates the effects of various intonation patterns as well as focus structures. The result is implemented and tested in a Chinese text-to-speech system. In general, the interrogative pattern in Mandarin Chinese is characterized by a high reference line and a high boundary tone at the end of a sentence. However, the resulting tone shape is not always rising as a result of the lexical tones. Focus is realized mainly by increasing the pitch range, but the exact implementation is complicated by some local tonal effects such as target shift. This paper will also explain the interaction of catathesis (pitch lowering triggered by specific tonal context) and focus in the direction of prosodic structure.
Synthesis of falling nuclear pitch accents
Authors: Liberman Mark Y. , Steele Shirley A.
Published: October 2005

A falling (“declarative”) nuclear pitch accent has a simple shape: an upward pitch obtrusion on the accented syllable, a fairly abrupt fall to near the bottom of the speaker's range, and a more gradual fall to the end. The synthesis algorithm in Anderson, Pierrehumbert, and Liberman (1983) decomposes this pattern into a H* pitch accent followed by an L phrase accent and an L boundary tone. It devotes four parameters to the realization of the H* accent (amount of rise, target F0 height, target duration, target time) and two parameters to the L phrase accent (target F0, target time). The parameters depend in part on properties of the accented syllable (e.g., prominence) and in part on characteristics of larger phrases (e.g., pitch range). The resulting time/F0 pairs are subject to interpolation and smoothing. This paper improves on the naturalness of the algorithm by incorporating findings from a recent study by Steele. In particular, the principles that determine the timing, magnitude, and alignment of the H* F0 rise and of the H* to L F0 fall have been improved.
Phonetic dependencies in syllables with full and reduced vowels
Authors: Kamm Candace , Macchi Marian
Published: October 2005

Speech synthesis using demisyllable concatenation relies on the assumption that initial and final demisyllables are phonetically independent of each other, aside from the need for smoothing the boundary. The success of demisyllable concatenation reported by Lovins, Macchi, and Fujimura [J. Acoust. Soc. Am. Suppl. 1 65, S130 (1979)] suggests that any phonetic dependencies that exist are not perceptually salient, at least for phrase-final syllables containing stressed vowels. To asess the independence assumption for naturally spoken English CVC syllables, the influences the initial consonants on syllable-final events and of final consonants on syllable-initial events were examined for long-duration syllables containing full vowels and shorter-duration syllables containing full and reduced vowels. Reduced syllables showed larger variation in formant frequencies at vowel offset across initial consonants than full-vowel syllables, including those with comparable vowel duration. Similarly, reduced syllables showed larger variation in formant frequencies at vowel onset across final consonants than syllables containing long-duration full vowels. To maintain the contextual variation in reduced vowels in demisyllable synthesis, it may be necessary to devise more complex smoothing rules or to include several versions of reduced-vowel demisyllables in the inventory.
High-frequency acoustic propagation in a range-dependent guiding-to-antiguiding ocean channel transition
Authors: Felsen L. B. , Ishihara T.
Published: October 2005

Variations in the ambient physical parameters in the ocean may be such as to change a depth-dependent profile with weak range dependence from guiding to antiguiding. This paper examines conversion of an initially well-guided high-frequency adiabatic mode into a nonguided sound field after passing through the transitional profile region. A theory is developed which smoothly patches a parabolic equation for the transitional domain onto trapped adiabatic mode fields on the guiding side and onto leaky modes on the nonguiding side. The parabolic equation is implemented numerically where it cannot be reduced to the simpler asymptotic forms. Numerical results for the dominant mode in a model profile confirm the analytical features of the theory, and reveal clearly the phenomenology of initial confinement in a surface duct, with subsequent detachment and “beaming” into deep water after passing through the transition to the antiguiding environment. [Work supported by ONR.]
Parabolic equation modeling of normal mode propagation in a wedge
Authors: Jensen Finn B. , Tindle C. T.
Published: October 2005

The parabolic equation model has been used to investigate the behavior of the “wedge modes” described in the experimental results of Hobaek, Tindle, and Muir [J. Acoust. Soc. Am. Suppl. 1 78, S70 (1985)] for propagation in a shallow water wedge. The wavefronts of wedge modes are not vertical, but are curved into arcs of circles centered on the wedge apex. Individual wedge modes can be examined by simulating a curved line source. A wedge mode propagates without coupling to other modes. By contrast, if the line source curvature is omitted it is not possible to excite a pure mode, and strong mode interference is observed. As wedge modes propagate upslope through their cutoff depth, their energy is dumped into the bottom as a beam. Any coupling to other modes as a mode passes through cutoff is very small and may be ignored.
Seismic propagation velocity measurements in arctic sea ice
Authors: Ozard J. M. , Brooke G. H.
Published: October 2005

It has been predicted that the seismic propagation velocities of sea ice affect the propagation of sound in ice covered arctic waters. Since very little data are available on propagation velocities, a series of in situ measurements of propagation velocities and associated density, temperature, and salinity profiles have been made in sea ice. Seismic energy from predominantly shear or compressional wave sources was propagated over ranges of a few hundred meters to two three-component geophone arrays. Propagation paths in smooth and in slightly rough annual ice were selected. Plate, flexural, and shear wave arrivals were clearly identified from their polarizations and particle velocities. A reduction in plate and flexural wave velocities was observed in the rough annual ice compared to the smoth annual ice.
Impulse-response and transfer-function measurements in rooms by m sequence cross correlation
Authors: Palmer E. Paul , Price Rodney D. , Burton Steven J.
Published: October 2005

The impulse response and transfer function between a sound source and receiver in a room can be measured using cross-correlation techniques with a maximum-length sequence as the signal source. A graphic representation of time evolution of direct sound, echoes, scattering, etc. (via the impulse response) and of spectral effects (via the transfer function) provide tools for acoustical design. The methods are illustrated for diffraction around an edge in an anechoic chamber. “Textbook”-like interference patterns are not seen because of the broadband nature of the signal. Instead, a quantitative measure of scattering, appropriate for speech and music, is obtained. Quantitative spectral measures are obtained using the transfer function. In an ordinary room, the effects of changing reflecting, scattering, and absorbing walls and objects and of displacing source and receiver are graphically displayed. The effects of modifying and adjusting sound-reinforcement systems are quantified. The impulse response, and computer-manipulated versions, can be convolved with appropriate speech and music signals for psychoacoustic testing.
Acoustical sealing at common walls
Authors: George Ballard W.
Published: October 2005

Caulking is one of the significant elements in the achievement of effective sound insulation between adjacent spaces or dwelling units. This paper presents calculations and discussion related to the benefits of caulking, with particular reference to sealing at the base of common walls and at electrical boxes. Data in the technical literature are used to derive an estimate of the effective “sound transmission class” associated with one or more beads of caulking, Using these data, calculations are made of sound leakage transmission for various configurations of the wall base. For analysis of double-stud walls, these have been modeled as acoustical plenums, and on this basis are seen to have some advantages in terms of the leakage path attenuation. A generally similar approach is used to calculate the attenuation achievable at boxes installed in common walls.
Uncertainty evaluation for the measurement of acoustic impedance in a freefield with two microphones
Authors: Champoux Y. , L'Espérance A.
Published: October 2005

The measurement of the acoustic impedance and/or the reflection coefficient of an acoustical system placed at the end of an impedance tube has recently generated great interest. The development of the two-microphone method has, for one thing, greatly increased the ease and speed with which such acoustical measurements can be made. The use of a small sample size inserted in a tube is, however, still required. Recently [J. F. Allard and B. Sieben, J. Acoust. Soc. Am. 77, 1617–1618 (1985)] suggested measurement of the acoustic impedance in the freefield. The present paper addresses theoretically the accuracy of such a freefield measurement. With the hypothesis of spherical wave propagation, the uncertainties associated with the finite-approximation error, phase mismatch and the near-field error are evaluated for the case of various acoustical materials. The importance of the selection of the appropriate type of wave propagation in the calculation of the reduced impedance at the surface of the sample is also demonstrated.
The effect of varying scale on acoustic propagation over a smooth surface
Authors: Bobak Michael T. , Raspet Richard
Published: October 2005

In an earlier paper we reported on the incorporation of a measured spatially varying turbulence model into the turbulence effects theory of Clifford and Lataitis [J. Acoust. Soc. Am. Suppl. 1 79, S19 (1986)]. In the earlier paper the theory was evaluated only in the limits L0 ≫ (L/k)1/2 or L0 ≪ (L/k)1/2, where L0 is the turbulence scale, k the acoustic wavenumber, and L the propagation distance. The validity of the above conditions was compromised by the varying scale of the measured turbulence model. In this paper we report on the evaluation of the complete integrals of Clifford and Lataitis [J. Acoust. Soc. Am. 73, 1548–1550 (1983)] and discuss how these results vary from the approximate integrals.
Transient behavior of oscillating bubbles
Authors: Prosperetti Andrea
Published: October 2005

Research on the behavior of bubbles in sound fields has mostly been concerned with the steady regime of oscillation. However, the use of the pulsed mode in ultrasonic devices for medical applications has rendered the transient behavior of practical interest as well. In this paper several aspects of the transient regime are investigated theoretically with particular consideration given to the thermal mechanisms affecting the internal pressure in the bubble. It is shown that these mechanisms introduce a “memory” effect in the bubble response. Analytical results are obtained for low forcing, and numerical ones when large-amplitude effects are significant. Phase change effects and gas-vapor mass diffusion in the case of hot liquids are also considered. [Work supported by ONR.]
Innovative underwater sound transducer designs and their analysis by use of bond graphs
Authors: Hanish S.
Published: October 2005

An innovative technique in modern underwater sound transducer design is to combine conventional transducers with miniature operational networks so as to achieve advanced receiving and transmitting responses for meeting newest design challenges. Operational amplifiers, field-effect transistors, and microprocessors are a few of the active or passive networks that can be so mated to underwater projectors and hydrophones. For all such electromechanical devices, the newer approach of analysis based on bond graph procedures will be demonstrated. A few examples will be analyzed in detail with the objective of both illustrating the use and advantages of bond graphs, and of unfolding the numerous possibilities for shaping transducer responses to accommodate a new generation of design demands.
Forward masking by multicomponent maskers with spectral uncertainty
Authors: Neff Donna L. , Callaghan Brian P. , Jesteadt Walt
Published: October 2005

Large amounts of simultaneous masking can be produced by small numbers of sinusoids spread over a wide frequency range, provided the frequencies of the sinusoids are changed with each stimulus presentation. In this study we examine the effect of similar stimuli in forward masking. Threshold for a 10-ms, 1000-Hz signal was measured at delays of 4, 8, 16, or 32 ms following the offset of a masker presented at 60, 70, or 80 dB SPL. The masker was a 1000-Hz sinusoid, a broadband noise, or a multicomponent complex. The complex was composed of 2–100 sinusoids that were drawn at random for each presentation from a 300–3000 Hz range, excluding frequencies within the critical band around the signal. Masking increased as the number of masker components increased. but did not exceed that produced by the sinusoid or noise. Slopes of masking were independent of component number and decreased as signal delay increased. The data have been analyzed in terms of models developed to describe masking produced by simpler stimuli. [Work supported by NIH.]
On burst noise detectability in syntehetic and natural speech
Authors: Kawahara Hideki
Published: October 2005

The relation between the hearing threshold of burst noise and some speech properties was measured by the sequential estimation method. A noise burst with a duration of 2–100 ms, LPC-based synthetic speech, and natural speech were used. Synthetic speech samples were generated from LPC parameters of the original speech samples—five Japanese vowels spoken by female speakers—with noise and pulse train excitation. Speech samples and a noise burst were added to produce stimuli, and the subjects were instructed to detect the noise burst in it. The detectability of a short noise burst (by 10 ms) was found to increase with increments of pitch duration and differ from vowel to vowel. However, the detectability of a relatively long noise burst (by 100 ms) seemed independent of excitation source parameters: The synchronization effect between short-term speech energy and minimum audible burst noise level was also observed for a very short noise burst (by 3 ms). A signal detection model of the human auditory system was proposed to confirm good correlation with these results. These results prove that it is possible to improve synthetic speech quality and waveform coding system performance.
Temporal effects in simultaneous masking and their influence on tuning curves in hearing-impaired listeners
Authors: Kimberley Barry P. , Nelson David A. , Bacon Sid P.
Published: October 2005

Recent investigations raise questions about the temporal development of tuning in the auditory system [S. P. Bacon and B.C. J. Moore, J. Acoust. Soc. Am. 80, in press (1986)]. They demonstrated that simultaneous masking psychophysical tuning curves (PTCs) were broader, on the high-frequency side, when the probe tone coincided with masker onset that when it was temporally centered in the masker. We replicated their experiment in normal-hearing listeners and extended it to hearing-impaired listeners who demonstrated abnormal PTCs. Simultaneous PTCs for 10 dB SL 20-ms probe tones, masked by 400-ms masking tones, were obtained with the probe at the onset and at the temporal center of the masker. Results from normal-hearing listeners confirmed earlier findings. However, in hearing-impaired listeners there was little change in PTC shape with temporal position. These data suggest that the mechanism responsible for the temporal effect in normal ears are ineffective in listeners with sensorineural hearing loss. [Work supported by NINCDS.]
Temporal masking curves and recovery from adaptation in hearing-impaired listeners
Authors: Nelson David A. , Freyman Richard L.
Published: October 2005

Temporal masking curves, obtained from 12 normal-hearing and 16 hearing-impaired listeners using 200-ms, 1000-Hz pure-tone maskers and 20-ms, 1000-Hz fixed-level probe tones, were fit by an exponential function with a single level-independent time constant. Normal-hearing listeners' time constants ranged between 37–67 ms, with a mean of 50 ms. Hearing-impaired listeners' time constants ranged between 58–114 ms and increased exponentially with hearing loss according to the function τ = 52e0.011(HL), when the slope (k) of the growth of masking was restricted to unity. When iterative fitting procedures included k as a free parameter, k values from normal-hearing listeners varied around unity (mean = 1.03), while those from hearing-impaired listeners were less (mean = 0.71). These data indicate that temporal resolution is poorer in hearing impaired listeners by factors as large as 2.3 for a hearing loss of 52 dB, but the major effect of hearing loss on the detectability of sequential signals is due to the sensitivity loss and to an exponential recovery process that is dependent upon sensory response not stimulus level. In impaired ears, sensitivity loss apparently reduces the sensory response to high-level maskers so that the recovery process is slower, much like it is for low-level maskers in normal-hearing listeners. [Work supported by NINCDS.]
Pharyngealization in Chechen
Authors: Kingston John , Nichols Johanna
Published: October 2005

An LPC analysis was used to extract formant frequencies from stop release through vowel in eight Chechen minimal and near-minimal pairs contrasting plain versus pharyngealized syllables of the structure pa, ta, ba, da (seven tokens of each, each pronounced by two native speakers). Pharyngealization proves to raise F1, lower F2 (with clear sensitivity to point of articulation of the stop), and lower F3. It thus has little observable effect on the consonant, but markedly increases the compactness of the vowel. The effect on the vowel is as predicted by Fant [The Acoustic Theory of Speech Production (Mouton, The Hague, 1960)], although the F1 raising is somewhat less than would be expected. The acoustic effect of pharyngealization is similar to that of uvularization, but not identical (the degree of F2 perturbation and the type of F3 perturbation differ). This explains both the fact that pharyngealization can co-occur with uvulars, and the cross-linguistic rarity of this co-occurrence. It also explains the near-identical patterning of pharyngealization in Chechen and Semitic languages, and uvularization in Kartvelian languages.
Normal mode propagation in a commercial catfish pond
Authors: Murray Lambert E. , Gilbert Kenneth E.
Published: October 2005

Acoustic propagation measurements were made in a commercial catfish pond in the frequency range 200–2000 Hz. A low-frequency cutoff was observed at 600 Hz. Above the cutoff frequency, modal propagation was observed. At 1000 Hz, measurements of propagation loss versus range indicated the presence of a single propagating mode. A second mode appeared at 1400 Hz and became stronger with increasing frequency. Measurements at a fixed range of the pressure field as a function of depth also indicated a single mode at 1000 Hz and showed a second mode as the frequency increased. Comparisons of the data with preliminary theoretical predictions will be presented.
Parabolic decomposition of the separable Helmholtz equation
Authors: Wood David H.
Published: October 2005

The solution of the separable Helmholtz equation is represented as the convolution of solutions of two related (formally) parabolic partial differential equations. Separable means that the square of the index of refraction is a function of depth plus a function of range and that the depth of the ocean is assumed to be constant. This representation decomposes the separable Helmholtz equation into two parabolic partial differential equations. One equation is the usual Fock-Tappert parabolic equation for sound propagation. The solutions of the second parabolic equation may be regarded as candidate kernels of special integral transformations, or transmutations. All of these equations have many solutions, of course, so initial and/or boundary conditions are presented that will determine solutions of the parabolic equations so that their convolution will give the Green's function for the Helmholz equation. Examples of such transmutation representations will be presented.
Sound radiated into the Arctic Ocean by cracks in the polar ice sheet
Authors: Langley A. J.
Published: October 2005

Ambient noise in the Arctic Ocean is caused partly by cracking of the ice sheet. Starting with a suitable “equivalent source” for fracturing processes, an analytical description of the radiated field has been derived when the ice sheet is modeled by an infinite, thick, elastic plate bounding a homogeneous fluid half-space. This simple model can be used to assess the importance of radiation damping, absorption, scattering, and ocean sound-speed profile in the production of real sound fields. Under mid-Arctic conditions at frequencies below about 20 Hz, the model indicates that radiation damping and absorption are very weak, and that a large contribution to the ambient noise could come from elastic waves in the ice that are scattered by inhomogeneities or edges of floes. Therefore, models relating low-frequency ambient noise to sources in the ice should take some account of scattering. At higher frequencies, absorption becomes more important, and the effect of scattering becomes harder to estimate because it depends upon details of the ice structure. [Work supported by Arctic Program, ONR.]
Waterborne and seismic partitioning of distributed noise in shallow water
Authors: Kuperman W. A. , Schmidt Henrik
Published: October 2005

The waveguide nature of a shallow water environment bounded below by a viscoelastic medium permits noise to couple into seismic waves. Geophone and hydrophone measurements [T. Akal et al., in Ocean Seismo-Acoustics, edited by T. Akal and J. Berkson (Plenum, New York, 1986), pp. 767–778] have shown that below a threshold frequency of about 10 Hz in 100 m of water, there is an increase in the vertical and radial components of the outputs of geophones as compared to no increase in the pressure output from an adjacent hydrophone. A previously developed wave theory of distributed noise in a stratified ocean [W. A. Kuperman and F. Ingenito, J. Acoust. Soc. Am. 67, 1988–1996 (1980)] used with the appropriate viscoelastic medium Green's function [H. Schmidt and F. B. Jensen, J. Acoust. Soc. Am. 77, 813–825 (1985)] explains this phenomena which occurs below the waterborne propagation cutoff frequency.
High sea state ambient noise near Bermuda
Authors: Cobb A. Donn , Von Winkle William A. , Browning David G.
Published: October 2005

The observed relationship between wind speed and ambient noise level has varied from ocean to ocean. Generally higher levels measured in southern hemisphere oceans have been attributed to fully developed seas, although this mechanism is not understood. Ambient noise data taken near Bermuda after a persistent (5 days) wind of approximately 40 kn are higher than previously observed and consistent with southern ocean measurements, thus supporting a developed sea state hypothesis. [Work supported by NUSC.]
Field manual for sound proofing of buildings in the vicinity of airports
Authors: Yaniv Simone L.
Published: October 2005

This paper summarizes the manual prepared for the FAA to provide uniform national guidance for sound-proofing existing buildings around airports in accordance with the goals set forth in FAR Part 150. The guidelines contained in the manual are quantitative rather than qualitative in scope. Procedures are given for estimating the noise reduction provided by existing buildings in the vicinity of airports, determining the amount of soundproofing required to achieve an adequate indoor noise environment, and for selecting cost-effective retrofit options. Although the manual is intended for use by technical people without specific training in acoustics, computations are required. Accordingly, examples will be presented to illustrate the step-by-step procedures, lookup tables, and graphs used.
An exterior enclosure sound level reduction (SLR) worksheet for use by architects and housing developers utilizing the external wall rating (EWR) method for aircraft noise
Authors: Hougland Dana S.
Published: October 2005

A worksheet calculation method was developed for architects and housing developers to calculate the exterior enclosure SLR of new residential units. The worksheet calculations are designed to be completed and submitted to the local building department as preliminary verification that new residential construction around a major commerical airport provides the required enclosure SLRs. The worksheet is based on the external wall rating (EWR) for aircraft noise [Sharp et al., “The Assessment of Noise Alternative Measures for External Noise,” Wyle Res. Rep. WR76-3 (April 1976)]. The SLR worksheet and a data base of regional constructions are incorporated into proposed revisions to the city/county building code. The results of SLR measurements made on a typical, new residence in the affected area are compared with calculated data on the same residence.
Use of the Shell Isolation Rating method in the design of an elementary school near a military air base
Authors: Johnson James A.
Published: October 2005

The National Bureau of Standards document NBS BSS 84, “Design Guide for Reducing Transportation Noise in and Around Buildings,” was adapted for use in evaluating several design options by an architect in the course of replacing a highly noise-impacted elementary school with a new facility on the same block of land. The dominant noise sources were military fighter aircraft operating in a traffic pattern which placed them approximately 1550 ft abeam the school, some 2500 ft from the runway threshold. The predicted Shell Isolation Ratings are compared to field-measured results at the school site in order to evaluate the method's utility as a design tool. Faculty response to the new facility is favorable, partly because a noise level reduction greater than that recommended by the military was found advisable, and was achieved. Computerization of the methodology will be presented.
A simplified math model and equivalent circuit for large, uniform, multilayered gratings of encapsulated compliant tubes irradiated by plane sound waves in water
Authors: Brigham G. A. , Woolley Barry
Published: October 2005

Detailed mathematical studies of encapsulated layers of compliant tubes indicate that the elastomeric effects can be reduced to a shear viscous damping and a shear wave stiffness loading in the layer equivalent circuit, which has been shown in earlier research to be a T network. Analysis of multiple layers yields the observation that the unsymmetric tube/ layer modes are strongly coupled to the difference of the pressure across the layer while the symmetric (compliant) modes are strongly coupled to the average of the pressure around each tube. A circuit interpretation reveals all symmetric modes in parallel with their net impedance, a shunt by the main branch which consists of the antisymmetric modes in parallel, all in a common T network. The theoretical derivations, coupling impedances, equivalent circuit, and comparison with both data and a large computer model are all presented in this paper.
Generic models of spatially distributed sensors and actuators
Authors: Busch-Vishniac Ilene J.
Published: October 2005

Traditional models of sensors and actuators typically represent the transducer by a series of interconnected, discrete, lumped elements. Such models are useful because the characteristic behavior of the transducer is described by ordinary differential equations. However, these models are limited to low-frequency regimes because they contain a finite number of elements. Further, they are not easily adaptable to transducers in which the behavior is explicitly a consequence of the continuum nature of transducing element, such as acoustic horns. Presented here are generic models of transducers in which the continuous nature of the transducer is stressed. The models may be classed into two types: those which apply to transducers in which the coupling between locations occurs only through the input and output ports, and those in which there is mechanical coupling between transducer locations as well. The former case may be modeled using coupled two-port theory, and the latter using augmented transmission lines. These techniques allow for spatially varying physical parameters, and apply regardless of the transducer type, function, and geometry.
Inexpensive microcomputer-based sound measurement apparatus
Authors: Hanson Roger J. , Ward Robert T.
Published: October 2005

Hardware and software kits (less than $350) have been developed which together with an Apple II computer can be used to make a variety of sound measurements suitable for educational purposes at the precollege level. Descriptions and demonstrations will be given of such systems including those developed by TERC (Technical Education Research Centers, Cambridge, MA) for junior high school science programs. The systems include amplifiers, A to D and D to A converters, and frequency analysis components all packaged in the form of plug-in cards or modules connected to the game port. A microphone and a speaker are also included. When used with the included software, the systems can perform the elementary functions of a digital oscilloscope, a sound spectrograph, and a frequency counter. Laboratory tests of the response of the systems to various signals will be reported.
Backscattering of light from spherical and slightly spheroidal air bubbles in water: A novel unfolding of the glory
Authors: Arnott W. Patrick , Marston Philip L.
Published: October 2005

The optical glory, which is related to a weak focusing of backscattered light, was observed for bubbles in water. This caustic is affected by small deviations from sphericity. Hydrodynamics causes freely rising bubbles in pure water to become slightly spheroidal if their diameter ≳ 250 μm. We modeled and photographed the near backward scattering from spherical and slightly spheroidal horizontally illuminated bubbles. Spherical bubbles produce backward-directed glory wavefronts having the local shape of a circular torus [D. S. Langley and P. L. Marston, Phys. Rev. Lett. 47, 913–916 (1981)]. Our model introduces the leading perturbation of those wavefronts resulting from a small deviation from sphericity. The cross-polarized scattering from a sphere has a fourfold symmetric azimuthal dependence; the patterns for spheroids are typically twofold symmetric. Detailed features of the modeled patterns are confirmed by the observations. This gives a specific example of broken symmetry resulting in an unfolding of a caustic which would otherwise have an infinite co-dimension. Related unfoldings should occur in certain acoustical scattering problems. [Work supported by ONR.]
Hyperbolic-umbilic diffraction catastrophes and the tracing of local principal curvatures of wavefronts
Authors: Marston P. L.
Published: October 2005

Focal sections characteristic of a hyperbolic-umbilic diffraction catastrophe (hudc) are known to be observable in light scattered from spheroidal drops [P. L. Marston and E. H. Trinh, Nature 312, 529–531 (1984)]. They should also be present in high-frequency sound reflected from curved surfaces or refracted by inhomogeneities. It is shown that a wave whose amplitude in the xy plane is exp[ik(g − ct)], will produce a farfield hudc focal section if g(x,y) = ax3 + 3γy2x)/6, where a and γ are related to the local principal curvatures (k1 and k2) of g for y = 0 by k1 = ax and k2 = γx. The apex angle Ψ formed by the caustics of the hudc is given by tan(Ψ/2) = (γ/α)1/2. Therefore, to predict the hudc pattern k1 and k2 are needed for points on the outgoing wavefront adjacent to the focal ray at x = 0, y = 0. These may be found by tracing up to the xy plane the local principal curvatures of the wavefront. This procedure was verified for the aforementioned light scattering problem; in agreement with data on acoustically levitated drops, it gives an(Ψ/2) = m/(12)1/2, where m is the drop's refractive index. [Work supported by ONR.]
Plane wave scattering from compliant tube gratings at oblique incidence
Authors: Audoly C. , Lamy P.
Published: October 2005

A computer model, based on a method presented by previous authors [R. P. Radlinski and M. M. Simon, J. Acoust. Soc. Am. 72, 607–614 (1982)] and extended to oblique incidence has been developed to calculate scattering of a plane wave from compliant tube gratings in water. Insertion loss and total pressure field at both sides of the gratings are given and compared to experiments. The cases of single- and double-layer gratings embedded in a viscoelastic layer or not are considered. For some cases of incidence, the excitation of a class of resonant modes of the tubes section causes significant changes in insertion loss curves. When the gratings are encapsulated the effects of incidence are less important.
Comparison of simulated peripheral auditory responses to vowels in noise with neural data
Authors: Payton Karen L.
Published: October 2005

A model of the auditory periphery, designed to fit neural responses to tones, has been shown [K. L. Payton, J. Acoust. Soc. Am. Suppl. 1 77, S80 (1985)] to predict many response characteristics of auditory-nerve fibers to vowel sounds in quiet [M. B. Sachs and E. D. Young, J. Acoust. Soc. Am. 68, 858–875 (1980)]. This paper examines the effects of background noise on model vowel responses and compares them to neural responses [M. B. Sachs, H. F. Voigt, and E. D. Young, J. Neurophysiol. 50, 27–45 (1983)]. In quiet, both the neural and model average rate responses saturate at high stimulus levels. Representation of vowel formants by the ALSR, a temporal measure of neural responses relatively insensitive to level, is also predicted by the model. When white noise is added, at + 10 dB S/N ratio, both the neural and model average rate responses saturate at lower vowel sound levels. However, the presence of background noise degrades the model ALSR responses more than it degrades the neural ALSR responses. [Work supported by NSF.]
The relationship between sexual and individual differences in lovebird calls
Authors: Wheeler Leslie A. , Lefebvre Jacques , Wimitzky Michel
Published: October 2005

Those of us who have tried to determine how acoustic information is transmitted in parrot calls have come up against a curious problem: while we have a pretty good idea of how parrots can use their calls to recognize each other as individuals, we cannot figure out how they recognize each other sexually. To try to solve this problem, our team changed strategy: if direct approaches fail, try an indirect approach. In short, to study sexual differentiation, we worked backwards and sideways from studies of individual differentiation. By putting together a jig saw puzzle whose pieces represent the results of psychoacoustic experimentation, of classical acoustic analysis, and of original techniques for acoustic information extraction, an image did indeed emerge and is presented in this paper.
Anatomical effects of intense tone stimulation in the ear of bony fishes
Authors: Cox Mardi , Rogers Peter H. , Popper Arthur N. , Saidel William M.
Published: October 2005

In an attempt to determine whether or not a place-type mechanism for frequency discrimination exists in the ears of bony fishes, an experimental investigation of three species was conducted. Goldfish, Oscars, and Kissing Gouramis were exposed to intense single-frequency sound fields for 2 h and then sacrificed. During the exposure, the fish were constrained inside a waveguide at a point of maximal acoustic pressure and minimal particle velocity. The saccular maculae were examined under a scanning electron microscope to determine the location of hair cell damage as a function of frequency. Preliminary results indicate that the location of the damage may not depend on frequency. [Work supported in part by ONR and NIH.]
Static and dynamic differences in perilymphatic potassium between scala tympani (ST) and scala vestibuli (SV)
Authors: Ohyama Kenji , Arakawa Eiichi , Salt Alec N. , Thalmann Ruediger
Published: October 2005

Cochlear perilymph has been regarded as a single, homogeneous fluid, although K is usually found in lower concentration in ST (3–4 mM) than SV (6–7 mM). Since perforation of the cochlea (to aspirate a sample or insert an ion selective electrode) releases cochlear pressure, allowing cerebrospinal fluid (CSF) (3 mM K) to enter, it has not been established whether the K difference is genuine or artifactual by contamination with CSF. In guinea pigs (GP) stringent precautions were used to prevent perilymph leakage and release of cochlear pressure during insertion of the ion selective electrodes. We found that K in ST is significantly lower than in SV, demonstrating for the first time a systematic physiological difference between the scalae. We have also found marked differences between the clearance of K in ST and SV following high K perfusion (20 mM) of guinea pigs (GP) with the cochlear aqueduct occluded. In general, the rate of K clearance from SV is 2–3 times slower than the clearance from ST. These data demonstrate that dynamic processes of perilymph homeostasis are not uniform throughout the cochlea and that concentration differences can be maintained across the spiral ligament. [Work supported by NIH and NSF.]
Identification of vowels in noise and in reverberation produced by a female talker
Authors: Nábělek Anna K.
Published: October 2005

Vowels produced by a female talker were less identifiable than previously investigated vowels produced by a male talker [A. K. Nábělek and P. A. Dagenais, J. Acoust. Soc. Am. 80, 741–748 (1986)]. Matrices of responses were obtained for normal-hearing and hearing-impaired subjects for three conditions: quiet, noise (S/N = 0 dB), and reverberation (T = 1.2 s). The vowels which were confused by normal-hearing subjects were also confused by hearing-impaired subjects. However, there were some pairs of vowels which were confused only by hearing-impaired subjects. There were also some differences between errors for the female voice and errors collected previously for the male voice. Differences in errors for the two talkers and two groups of subjects will be discussed. [Work supported by NIH.]
Ocean acoustic tomography and acoustic propagation
Authors: Spindel R. C. , Worcester P. F.
Published: October 2005

Ocean acoustic tomography is a method for remotely sensing deterministic and stochastic variations in the ocean sound speed field. The fundamental tomographic measurement is sound speed, and therefore tomography directly provides acoustic propagation models with this essential, first-order, environmental information. In one form or another the various sound propagation codes rely on sound speed data in either 2-, 3- or 4-dimensional form. Experiments have shown that both mean and range-varying sound speed data can be obtained using tomography, and that when appropriate assumptions are made about the known horizontal and vertical covariance structure of the ocean, these data are spatially continuous. Thus it is not necessary to choose an interpolation scheme for discrete profiles that may be mathematically sensible, but physically less meaningful. Further, since the tomographic measurement itself uses propagating acoustic waves, it affords an opportunity to obtain simultaneously selected sound propagation parameters. We discuss these and other aspects of tomographic remote sensing and its application to acoustic propagation.
Exterior wall rating (EWR), a single number index for rating the sound transmission loss of A-weighted sound levels for exterior facades
Authors: Sutherland Louis C. , Mange Gary
Published: October 2005

A single number index, called the exterior wall rating, or EWR, has been developed for rating the sound transmission loss of A-weighted sound levels for exterior facades. This index is closely patterned after, but distinctly different from, the STC single number index. The latter provides a reliable rating for the sound transmission loss of interior partitions for typical interior sounds, but is not suitable for assessing the sound transmission loss of exterior walls to major sources of outdoor noise. However, by applying principles similar to those upon which the STC rating was developed, a practical index was constructed which can reliably rate exterior walls in terms of their ability to attenuate A-weighted sound levels. EWR originally evolved out of a systematic analysis of 1/3-octave-band sound transmission loss data for over 225 wall constructions and 33 different window constructions with four different relative areas from 0%–20% of the wall areas. From this analysis of over 22 500 combinations of structural assemblies, EWR was found to be a substantially more accurate predictor of attenuation of A-weighted sound levels than other candidate indices. These included a modified STC, SIL, and average TL values for 16 1/3-octave bands. EWR includes a necessary correction for the different spectra of aircraft and highway noise, and thus provides an efficient method for the design or analysis of sound insulation treatment of buildings to attenuate noise from these major outdoor noise sources. One such application is considered in paper HH4 by David Brown [J. Acoust. Soc. Am. Suppl. 1 80, S67 (1986)]. The basic methods for calculating EWR values from standard TL data are defined to encourage sound-transmission-loss-testing-laboratory operators and users to apply this practical method for rating sound transmission loss of exterior walls.
Sound transmission through windows of high-rise buildings located adjacent to freeways and major traffic arterials
Authors: Christoff Jerry P.
Published: October 2005

A mathematical theory was developed for sound transmission through single glazed windows assuming a line sound source and the appropriate angles between the location of the window in the building and the source. The predicted internal sound pressure levels using the theory and sound transmission loss values from ASTM E90 are compared to measurements in several buildings.
Noise transmission through building corridors and staircases in apartment houses. Effects on noise control of apartments
Authors: Sotiropoulou Alexandra G.
Published: October 2005

A series of noise attenuation measurements was carried out in long corridors and staircases at two, six-storied apartment houses in Athens. Such spaces are often liable to considerable transmission of building noises into apartments, due to their tubelike shape and their nonabsorptive treatment. Test spaces were treated in ordinary plaster; floors and stairs were covered in marble. Attenuation of 0 dB/m was measured in all corridors at all frequencies. In staircases, noise linearly decreased away from the source; the mean frequency attenuation was 5.5 dB per story. The effect of these findings within apartments was then evaluated, considering slamming doors, raised voices, etc. operating in builing corridors. In these evaluations, the sound insulation of typical entry doors of apartments was taken from measurements (STC 14). In all cases NR values exceeded the criterion value NR 35 [J. T. Broch, Acoustic Noise Measurements (B&K, Denmark, 1971), 2nd ed., Chap. 3, 35–39]. These results show that ordinary construction of corridors, staircases, and apartment doors is inadequate to protect apartments against usual building noises, and that construction improvements are required.
A new score input method for computer music
Authors: Shyu R.
Published: October 2005

To reduce the time and effort of score inputting and score proofreading for computer music, a new score input method was designed, implemented, and investigated. This new method allows scores to be entered through a regular computer keyboard using the minimum possible number of keystrokes, and be displayed, with the aid of computer graphics on a computer monitor in original musical notations. The number of keystrokes is minimized using the idea of “music abstraction.” An often used musical idea, no matter how many notes it consists of, can be abstracted as a single icon—called the “musicon” (music icon), and input using one keystroke each time it is needed. A study evaluated this design in terms of the speed of input and proofreading. The musicon can not only save keystrokes, it can also become a compositional tool by helping the composer to organize musical ideas in the same way a thought processor like the Thinktank can help a writer.
Acoustic parameters of violin vibrato
Authors: Rothman Howard B. , Arrayo A. Antonio
Published: October 2005

Studies of vocal vibrato conducted in 1930 indicated that the great singers produced a pulsation rate ranging from 5.9–7.8 pulses per second (pps). Studies conducted during the last decade show singers' vibrato pulsations ranging from 4.9–6 pps. The slower pulsation rate of modern singers reflects a different aesthetic that prevails today. Studies of violinists' vibrato conducted in 1930 indicate a pulsation range of 5.5–7 pps. Other findings from early studies indicate that violin vibrato rate remains constant as tonal amplitude varies and vibrato amplitude changes with tonal intensity. The present paper will examine the relation between the vibrato of violinist's representing an earlier aesthetic and those of today. Samples of sustained violin tones were obtained from acoustic, electric, and stereo recordings of great violinists of the past and the present. The samples were digitized using a 16-bit A/D converter at a sampling frequency of 10 kHz. Each digitized sample will be converted to a useful format for making purposes in order to derive information on vibrato pulse rate, the mean frequency of the tone, the semitone deviation around the mean, percent frequency deviation and percent amplitude deviation around the mean amplitude.
Science in the service of the performing arts. Section I: Background
Authors: Veneklasen Paul S.
Published: October 2005

Has orchestra performance reached its zenith? What can science offer for sustenance? The recognized limitations are exposed. The pioneering work of physicists is reviewed. The inspiring efforts of Leopold Stokowsky are paid special tribute and his innovative leadership toward orchestral balance and dynamic performance are stressed. Experiments with spatial factors in performance are described.
Science in the service of the performing arts. Section III: Experiments with full orchestra and conclusions
Authors: Veneklasen Paul S.
Published: October 2005

A unique series of tests with the Seattle Orchestra in the calibrated Seattle Auditorium was staged to experiment with section arrangement within the orchestra enclosure. New values for relative and absolute power output from instruments and sections as a function of dynamic playing level were derived. Results demonstrate that relative placement and elevation of sections can be used to greatly improve intersection balance and choral effects. A unique and strange stage arrangement emerges.