bluuebunny/crossref_metadata_2025 huggingface dataset:
Phonetic realization of prominence among lexical tones in Mandarin Chinese.
Authors: Bao Mingzhen , Wayland Ratree
Published: October 2013

Linguistic prominence is defined as words or syllables perceived auditorily as standing out from their environment Terken (1994). It is explored through changes in pitch, duration, and loudness Ladd (1996). In this study, phonetic realization of prominence was investigated among lexical tones in Mandarin Chinese. The primary concern was to compare how accent and focus are acoustically realized under four conditions: (a) unaccented and unfocused, (b) accented but unfocused, (c) unaccented but focused, and (d) accented and focused, among four tones. Ten native speakers of Chinese were recorded reading materials in a natural fashion. The recorded data were segmented and acoustically measured for acoustic parameters: vowel duration; mean and maximum of intensity; and mean, maximum, minimum, and slope of F0. The results showed that vowel duration lengthening was the main acoustic parameter associated with accent, while an increase in vowel duration, mean and maximum of intensity and F0, and slope of F0 was associated with focus realization. It was also found that acoustic parameters used to realize focus were differentially ranked and varied from tone to tone. These results suggested that phonetic realization of prominence in Mandarin Chinese was affected by category of prominence (i.e., focus or accent) and tonal contexts.
Perceived age in normal and disordered voices.
Authors: Bourgeois Dorothy , Brown W.S. , Shrivastav Rahul , Rothman Howard , Harnsberger James D.
Published: October 2013

An experiment was conducted to identify the contribution of voice quality to perceived age. Voice quality effects were assessed in age estimation experiments using (1) natural pathological stimuli that incorporated voice qualities of interest and (2) young normal voices in which two voice cues, hoarseness and tremor, were modified through resynthesis. The disordered samples included single sentences from 227 talkers included in the Kay Elemetrics database of disordered samples. The resynthesized samples were sentences from ten young males in which (1) the f0 contour was multiplied by a random number within a fixed range (hoarseness) or (2) a 5–9-Hz wave with an amplitude of 7.5% of the original f0 value was incorporated (tremor). Sixty navive listeners estimated all speakers ages in years. The results demonstrated that disordered voices were overestimated in age by 11 years, with the greatest mismatch in chronologic and perceived age reaching 47 years older. The addition of synthetic tremor and hoarseness shifted perceived age older by 8 and 5 years, respectively. In summary, voice quality appears to play a significant role in the perception of perceived age, comparable to or exceeding other cues that have been identified to date.
Perception of falling and rising pitch contour contrast: Effects of first language background.
Authors: Wayland Ratree , Bao Mingzhen , Kaan Edith
Published: October 2013

The main objective of this study is to examine the ability to discriminate falling and rising pitch contour contrasts among native speakers of a tonal language (Chinese) and native speakers of a nontonal language (English). Linearly falling and rising pitch contours on [ba:] syllables are presented to participants in (1) the “same different categorial” discrimination task and (2) an “oddball” detection task. Preliminary results obtained from 10 Chinese and 12 English speakers suggested that (a) native Chinese speakers found the falling contour to be easier to discriminate than the rising contour, while the ability to discriminate between the two pitch contours was comparable among the English speakers, (b) reaction time for the falling contour false alarms was longer than for the rising contour among the English speakers, (c) no difference in either “detection” rate or “reaction” time between the two contours was found among both groups of speakers. More data will be collected from both groups of speakers and from speakers of another tonal language. Language general as well as language specific factors will be considered to account for the patterns of results obtained.
The production and perception of prenuclear second occurrence focus.
Authors: Wake Melissa , Bishop Jason , Panganiban Cathryn
Published: October 2013

Semantic focus in English is typically marked by intonational prominence, most canonically by a pitch accent. One case that has been presented as an exception to this generalization, however, is that of second occurrence (SO) focus. An SO focus is a repeated but focused item, usually associated with a focus sensitive operator such as “only” or “even.” Previous studies have suggested that SO foci lack pitch accents for phonological rather than information structural reasons, in most cases examining such foci in the postnuclear domain. We present acoustic and phonological data that demonstrate that SO foci also lack considerably in intonational prominence (particularly in terms of F0) when prenuclear, although they show increased duration. Additionally, the perceptibility of prenuclear SO focus is tested. Perceptually weak prosodic marking would suggest an important role for pragmatics in a focal interpretation, as has been suggested previously for SO focus.
Perception of contrastive meaning through the L+H*L−H% contour.
Authors: Dennison Heeyeon Y. , Schafer Amy J. , Anderson Victoria B.
Published: October 2013

This study establishes empirical evidence regarding listeners’s perceptions of the contrastive tune [L+H*L−H%; e.g., Lee et al. (2007)]. Eighteen native English speakers heard three types of test sentences: (1) contrastive, “The mailbox was(L+H*) full(L−H%),” (2) positive neutral, “The mailbox(H*) was full(H*L−L%);” and (3) negated neutral, “The mailbox(H*) was not(H*) full(H*L−L%).” The participants first scored them by naturalness, and then typed continuation sentences based on the perceived meaning. Three other native English speakers independently coded the continuations to evaluate participants’ interpretations of the test sentences. The results clearly demonstrated that the L+H*L−H% tune generated contrastive meanings (e.g., “…but the mailman took the mail and now it is empty” significantly more often than both the positive and negative neutral counterparts. Moreover, sentences presented in the contrastive tune were perceived as natural utterances. High coder agreement indicated a reliable function of the contrastive tune, conforming to the existing literature based on intuitive examples [e.g., Lee (1999)]. Interestingly, however, the contrastive tune produced the expected contrastive meaning in only about 60% of trials (versus less than 10% contrastive continuations for the other contours). This finding shows that the interpretation of the L+H*L−H% contour is more complex than previously suggested.
Perception of emphasis in urban Jordanian Arabic.
Authors: Jongman Allard , Combest Sonja , Herd Wendy , Al-Masri Mohammad
Published: October 2013

Previous acoustic analyses of minimal pairs of emphatic versus plain CVC stimuli showed that (1) emphatic consonants have a lower spectral mean than their plain counterparts and (2) vowels surrounding emphatic consonants are characterized by a higher F1, lower F2, and higher F3 than vowels surrounding plain consonants [Jongman et al., J. Acoust. Soc. Am. 121, 3169 (2007)]. The present perception study explores whether Arabic listeners’ recognition of emphasis is based on information in the consonant or vowel. Monosyllabic words were used with emphatic and plain consonants in either initial or final position. By means of cross-splicing, the emphatic consonant or its adjacent vowel replaced the plain consonant or its adjacent vowel. Thirty Jordanian listeners participated in the experiment. On each trial, they indicated which word (emphatic or plain) they heard. Results show that the contribution of consonantal and vocalic information to the perception of emphasis depends on vowel quality: In the context of |a|, listeners seem to make their decision primarily based on the vowel while in the context of |i| and |u|, properties of the consonant carry more weight in this decision. The perceptual data will be compared to the acoustic measurements. [Research supported by the NSF.]
Duration of tone sandhi in Mandarin Chinese.
Authors: Yang Bei
Published: October 2013

Tone sandhi is the tonal alternation when they are connected in speech flow. Six types of tone sandhi of disyllabic words in Mandarin Chinese are investigated in this research, including the neutral tone, the dipping tone alternation, /bu/, /yi1/, /yi2/, and double change (both of tone changes in a disyllabic word). The paper explores the duration of these six types and whether the neutral tone can change into the citation tones (level, rising, dipping, and falling tones) if we change the duration of the neutral tone. Five Chinese native speakers participate in the study. Two tasks are used to elicit data. First, speakers are required to read 40 disyllabic words. The second one is an identification task. The duration of eight neutral tones are elongated by acoustic technology. The participants hear the eight processed neutral tones and eight unprocessed neutral tones, and are asked to judge the tone types. The results indicate that the neutral tone has the shortest duration, and the duration of other sandhi tone is shorter than that of the normal citation tones. The data also show that the neutral tone and citation tones can be altered based on duration and pitch.
Signal processor for detection of signals in cluttered environments.
Authors: Wagstaff Ronald , Rice Heath
Published: October 2013

The well-publicized experience of the USS Cole in a foreign port demonstrates the potential danger our military ships are frequently exposed to. When docked, they are the most vulnerable to attack by small fast boats that can hit and run before their threat is recognized, and defenses can be activated. This is a challenge that has many facets. Attack by a small high-powered fast-boat is just one type of threat. However, it is important. One way of quickly identifying a fast-boat is with an underwater acoustic sensing system. Such a system is not without challenges. Harbors are typically busy and contaminated by many forms of acoustic clutter. Detecting and separating the signals of fast-boats from among the clutter are difficult tasks. Fortunately, a signal processor has been developed with highly coherent fast-boat signals, and harbor clutter in mind. This fast-boat processor invokes temporal coherence constraints, by degree, to strip away incoherent noise and less coherent shipping signals, and leaves the fast-boat signals exposed. This signal processor will be discussed, and the results will be presented to illustrate the substantial signal-to-noise ratio and automatic signal detection gains that can be achieved.
Hardware and software solutions to noise in resonance measurements.
Authors: Gladden Joseph
Published: October 2013

Resonance measurements have the benefit that the system itself is a natural signal amplifier with a gain proportional to the quality factor (Q) of the resonator. However, even this small respite from Murphy’s law is not always enough to coax weak resonance signals out of a noisy background. In this talk I will discuss several aspects of improving signal to noise ratios in resonant ultrasound spectroscopy measurements using both hardware and software based solutions such as custom low-noise preamplifiers, lock-in amplifiers, dynamic averaging during data acquisition, and nonlinear fitting of noisy and overlapping (low-Q) peaks to an analytical model. Some particular issues of signal transmission across high-thermal gradients will also be discussed.
Identifying individual clicking whales acoustically amid the clutter of other clicking whales.
Authors: Ioup George E. , Ioup Juliette W. , Pflug Lisa A. , Tashmukhambetov Arslan M. , Sidorovskaia Natalia A. , Thompson Charles H. , Tiemann Christopher O.
Published: October 2013

Exceptionally clear recordings of sperm whale (Physeter macrocephalus) codas reveal time and frequency properties, which show that clicks within a coda are remarkably similar to each other but that they can differ from clicks in other codas. This is consistent with the hypothesis that individual whales can be identified by the characteristics within their codas. Research has centered on the cluster analysis of these codas to help establish whether acoustic identification of individuals is possible. Recently the cluster analysis has been made more robust. This increases the confidence in the applicability of the approach. Data are now available to couple visual sightings and acoustic tracking with recordings for acoustic identification to give an independent verification of the analysis. Acoustic identification of individuals has also been attempted using isolated echolocation clicks of sperm and beaked whales (Mesoplodon densirostris and Ziphius cavirostris). Although this is a more difficult and problematic undertaking, there has been some promising cluster analysis. Again data for acoustic tracking and visual observations are now available with the recordings for acoustic identification using echolocation clicks to test and perhaps validate the method. [Research supported in part by SPAWAR.]
Clutter prediction using artificial neural networks.
Authors: Ioup Juliette , Lohrenz Maura , Gendron Marlin
Published: October 2013

Clutter is a known problem in electronic geospatial (map) displays, on which many different types of data can be combined and presented as a single image. In this context, clutter may be thought of as an overabundance of information, which reduces display usability by the viewer. To declutter a geospatial display, it is necessary to first predict the amount of clutter a human observer might perceive. Computer-aided classification of maps according to the amount of clutter likely to be perceived by a human viewer is the goal of the research described here. Artificial neural networks are among the possible choices of computing techniques that can be used for this task. The network is trained using prior clutter classifications of training maps made by humans, so that automated prediction of clutter for a new map is possible. The objective is to have the network classify maps according to clutter as perceived by human judges. Several neural network algorithms and trials with data consisting of cluttered map classifications and response times by human judges are described. The choice of input features, including the use of principal components, is discussed. Preliminary results with test maps show good prediction of clutter.
Uncertainty and resolution in continuum inversion of ocean bottom geoacoustic properties.
Authors: Ganse Andrew A. , Odom Robert I.
Published: October 2013

Inversion of ocean bottom geoacoustic properties from acoustic receptions in the water column is a nonlinear inverse problem that is inherently unstable and nonunique. One common approach to stabilizing this problem is to assume that the ocean bottom is made up of a small number of layers. The solution from this approach does allow one to reproduce the scattered sound field if all the other experiment parameters such as frequency and geometry are also reproduced. However without extensive prior information about that ocean bottom, this approach yields only one of many equivalent nonunique solutions and may not accurately describe the actual ocean bottom itself. An alternate approach, which may allow one to reuse the results later with a different frequency or geometry, is to use the tools of geophysical continuum inversion to specify the degree of nonuniqueness by quantifying both the uncertainty and limited resolution of the continuum bottom solution. This work compares inversion uncertainty and resolution results for different formulations of the data (e.g., matched field versus matched modes versus waveform), different geometries, and different formulations of the uncertainty (e.g., normally distributed versus including some higher-order moments). [Work partially supported by ONR.]
Time domain integration to improve geoacoustic parameter estimation.
Authors: DelBalzo Donald , Leclere James , Ioup George
Published: October 2013

Shallow-water acoustic predictions are affected by uncertainty in sediment property characteristics. Inverse methods using controlled active source signals have been developed to estimate seabed properties. However, some applications prefer a more covert approach. Our work is focused exclusively on passive inversion techniques using signals from surface ships of opportunity. This study addresses the accuracy of low-frequency (100 Hz) matched-field correlations and subsequent geoacoustic estimates using signals from moving surface ships with unknown source levels at unknown ranges. A time-staggered technique is employed to reduce ambiguities in thick-sediment descriptions, with ever increasing confidence as time evolves. Matched-field techniques are applied in a simulated shallow-water environment with a single vertical line array and high signal-to-noise ratios. The simulations indicate significant potential for accurate estimates of thick-sediment characterizations of grain size and layer thickness out to ranges of tens of water depths in shallow water, despite moderate mismatch conditions in the environmental model. [Work sponsored by SPAWAR.]
Russell Johnson: The Bolt Beranek and Newman years.
Authors: Cavanaugh William J.
Published: October 2013

In 1954, the author and Russell Johnson both joined the architectural acoustics staff of the pioneering research and consulting firm, Bolt Beranek and Newman (BBN), in Cambridge, MA. Just over 16 years later, in 1970, after exposure to some of the brightest talents in the relatively new discipline of applied acoustics, both left BBN to form their own independent consulting firms: Cavanaugh, a general consulting practice, and Johnson, which was to become an internationally renowned firm, providing comprehensive services on all phases of performance facility design including acoustics. In the mid-1990s, the author began the process of nominating his long time friend and colleague for the Acoustical Society’s prestigious Wallace Clement Sabine Medal which was awarded in 1997 with the citation “for contributions to the understanding of the acoustics of performance spaces and the design of concert halls, theaters and opera houses throughout the world.” This paper traces Russell Johnson’s developing performance facility design interests from his early pre-WWII days, his US Army wartime service, his postwar studies at Carnegie Tech (now Carnegie Mellon University), and at Yale as well as his “extended” initial committment of two years at BBN to learn all he could about performance space acoustics.
Tribute to Russell Johnson: W. C. Sabine’s personal paper.
Authors: Beranek Leo L.
Published: October 2013

Russell Johnson was one of the most active acoustical consultants involved with concert hall design. He was a Senior Consultant at Bolt Beranek and Newman in Cambridge before he founded Artec. Sabine’s interactions with Mr. Johnson will be featured. In 1975, the notebooks of Wallace Clement Sabine were discovered and in 1979 his consulting files were discovered. Both findings were reported [J. Acoust. Soc. Am. 61, 629–639 (1977); J. Acoust. Soc. Am. 69, 1–6 (1981)]. By chance, Sabine’s personal papers were discovered recently and highlights from them will be presented with emphasis on his European activities from 1906 to 1917.
Russell Johnson: Four decades of collaboration.
Authors: Wolff Robert
Published: October 2013

Collaboration of Russell Johnson at Bolt Beranek and Newman, Russell Johnson Associates, and Artec Consultants Inc., from 1966 to 2001, with focus on fundamental approaches to acoustics design and consulting gleaned from experiences with Russell Johnson. Insights into Johnson's beliefs about the relation of acoustics design and consulting to theater design and to buildings for the performing arts will be discussed.
Russell Johnson’s “University of Artec”.
Authors: Essert Robert
Published: October 2013

Johnson’s legacy was one of passion for holistic design excellence in performance buildings. Architecture and theater were early passions. His interest and skill in acoustical design was a means to influence as much as he could of the auditorium architecture because he cared about quality for the performers and audiences and also because he wanted to express his design aesthetic. I had the privilege of being at Artec from 1980 through 1996, a period when the firm outgrew the home office and emerged into the big time. Although the complexion of the firm changed over those years, Johnson’s focus on quality and learning carried through. I will explore these two threads—quality and learning—as he motivated clients, architects, and the Artec staff to do excellent work, with examples of both process and creativity.
Auditorium acoustics newsletters, edited by Russell Johnson.
Authors: Rosenberg Carl J.
Published: October 2013

From January 1968 to May 1970, Russell Johnson was the principal editor of an internal newsletter at BBN called Auditorium Acoustics. Review of the 43 extant issues presents an interesting perspective on topics of concern and interest to Johnson at that time and reflects on the public attitudes toward acoustics and concert hall design. This paper shares some of those perspectives.
Building on the shoulders of a giant: Using technology to extend biosonar research pathways first blazed by Sam H. Ridgway.
Authors: Cranford Ted
Published: October 2013

Underwater biosonar research began in the middle of the last century by a handful of pioneers. Among the debates that raged in the scientific literature for the first 30 years were (1) the origin of biosonar signals and their formation into a transmitted beam and (2) the pathways and mechanisms for sound reception. Ridgway and his colleagues (1980) provided definitive proof for the nasal origin of sonar signals using electromyography and small pressure catheters inserted into various airways. Ridgway also collaborated on a series of experiments that attempted to discern the structure and function of the tympanoperiotic complex. My colleagues and I have combined remote imaging technology, high-speed video endoscopy, and finite element analysis to pinpoint the site of sonar signal generation, posit novel sound propagation pathways into and out of the heads of various odontocetes, and uncover new elements of the structure and function of the tympanoperiotic complex. These results will be presented in light of Ridgway’s pioneering work.
Non anthropogenic deafness in marine mammals: Hearing that is going, going, gone.
Authors: Ketten D. R. , Arruda J. , O’Malley J. , Cramer S. , Hammock J.
Published: October 2013

In humans, hearing is absent or diminished as a result of congenital defects, aging, noise exposures, traumatic events, and disease. Until concern arose about anthropogenic noise impacts on marine mammals, little was known about the mechanisms or incidence of marine mammal hearing losses. Over the past decade, we have gained substantial information from behavioral and electrophysiologic audiometres, in vivo imaging, and postmortem examinations. Dr. Sam Ridgway has been a pivotal element in these investigations, pioneering many of the techniques and facilitating broad collaborative studies. In this paper, the results of computerized tomographic and histologic studies of pinniped and cetacean ears, the majority of which Dr. Ridgway supplied, will be presented. The data show that marine mammals sustain precipitous and progressive hearing loss from multiple etiologies, including labyrinthitis, infestations, trauma, chronic multistage otitis, and presbycusis. In particular, older dolphins and seals develop degenerative pathologies (neural, hair cell, support cell loss, and demineralization) paralleling presbycusic changes in older humans. For captive cases, the distribution of inner ear pathologies will be compared with their premortem hearing curves to demonstrate the feasibility of back-projection hearing analyses on ears from noncaptive animals to better understand hearing status of wild populations. [Work supported by the ONR and the NIH/NIDCD]
A Forrest Gump effect? Being “there” for surprises and delights in cetacean and pinniped neurobiology.
Authors: Ridgway Sam
Published: October 2013

Anaesthesia research enabled collaborations with pioneers in animal bioacoustics and neurobiology. Being “there” with Evans, Schusterman, and Scott Johnson stoked interest in hearing. Surgery on the ear with McCormick and Wever helped to elucidate sound conduction. In Wever’s laboratory were also Simmons, Fay, and Saunders. (Simmons' bats were there. Bringing giant turtles and dolphins to Princeton was challenging.) With Bullock, recordings were made from auditory areas of the dolphin brain demonstrating separate centers for pulse and whistle responses. Suga helped with similar sea lion research. Sleeping seals transmitted their EEGs from pools atop Harrisons' department in Cambridge. With Woods and Galambos, far field auditory responses were characterized and correlated with the direct responses. Event-related brain potentials were also described. Discovering a deaf/mute dolphin with Don Carder and finding others with presbycusis were a surprise (ears eventually went to Ketten). Having Finneran, Schlundt, and Houser take over marine mammal TTS and sonar issues, as well as sound production work with Moore and Cranford, was delightful. There on Oahu with Mohl, Au, Nachtigall, and Supin when a baby sperm whale came onto Maui for testing again illustrated the Gump effect: “Life was like a box of chocolates. You never know what you’re gonna get.”
Acoustic classification of battlefield vehicles based on their seismic detection.
Authors: William Peter , Hoffman Michael
Published: October 2013

Identification of battlefield vehicles using a wireless sensor network is an event driven application that requires simple detection and energy efficient classification. Seismic and acoustic sensors have the capability to detect and track targets in a passive non-line-of-sight manner. The proposed approach uses seismic emissions for event detection and acoustic emissions for classification of detected events. Seismic detection using unpowered geophones achieves minimal energy for wakeup and event detection in addition to elimination of wind and background noise events. Time domain extracted features from the acoustic emission of vehicles are very efficient in battlefield vehicle discrimination preserving the coupled harmonic signature for both tracked and wheeled vehicles. We propose a simple energy efficient time domain detection and classification scheme that enables the sensor node to perform detection, feature extraction, and classification. Classification of acoustic features is performed using a multilayer feedforward neural network. The proposed approach shows that selective time domain acoustic features surpass equivalent spectral features. Evaluation of the proposed approach using recorded data shows an average classification rate (single node and single event) that exceeds 83% and an average false alarm rate of 16% (over both tracked and wheeled vehicles).
Constructing and using a low cost speckle pattern interferometer for analysis of musical instruments.
Authors: Morrison Andrew
Published: October 2013

Following the design of Moore [Am. J. Phys. 72, 1380 (2004)], a speckle-pattern interferometer for use in exploring the mode shapes of vibrating structures, especially musical instruments, has been constructed. The interferometer was built primarily by undergraduates with mostly common optical elements found in any undergraduate optics laboratory. The interferometer uses a FireWire (IEEE 1394) camera, which has a built-in frame-grabbing capability, eliminating the need for expensive frame-grabbing hardware. The interferometer has been used to study vibrating structures such as snare drum heads, mandolins, and a tennis racket. The interferometer has also been used to study the the vibrational properties of a cured carbon fiber disk. The design and implementation of an affordable speckle-pattern interferometer along with a brief overview of some of the results of research projects conducted with undergraduate students will be presented.
Drum tuning: An experimental analysis of membrane modes under slightly nonuniform tension.
Authors: Worland Randy
Published: October 2013

Results of an experimental study of normal mode vibrations in single-headed musical drums under nonuniform tension will be presented. Although uniform tension is often assumed in theoretical treatments, in practice the musical drum only approximates this condition, even after careful tuning by the drummer. This study investigates the behavior of normal mode shapes and frequencies under (slightly) nonuniform tension, as they relate to the tuning process. In particular, the role of the (1,1) mode will be described. Experimental results include electronic speckle pattern interferometry images of modal shapes along with the associated frequencies. A finite element model will be used for comparison with the experimental results.
Radiation of guitar loudspeakers.
Authors: Timm Heiko
Published: October 2013

Loudspeakers of guitar amplifiers used by electric guitarists are analyzed in terms of their radiation characteristics. This was performed using an acoustic camera consisting of 128 microphones. The data recorded were digitalized with a sample rate of 48 kHz and analyzed with methods of near field acoustic holography (NAH) and statistical optimized NAH. By these algorithms an acoustic hologram was obtained. The radiation is visualized to get information about the different parts of the complete electric guitar sound box. Differences in sound between different loudspeaker constructions can be explained by taking this close look at the sound coming out of the speakers. The radiation behavior, the impulse behavior, and the diffraction of sound coming from the backside of the speaker are investigated in this way. So the amount of diffraction of sound influencing the overall character of the speaker is also addressed.
Understanding the acoustical implications of Underwriters Laboratory listings.
Authors: Golden Matthew
Published: October 2013

With today’s ever more complicated building design, acoustical consultants should be aware of how their recommendations affect other aspects of floor/ceiling design. The acoustical ratings must be balanced with the need for fire rated assemblies as well as structural requirements. As the industry leader in the listing of fire rated designs, the Underwriters Laboratory (UL) maintains a list of assemblies that will meet various levels of fire resistance. These listings are very detailed and even slight changes to the design can have a profound impact on the assembly’s fire resistance rating. This paper will compare various listed wood-frame floor/ceiling assemblies with respect to acoustical design. These comparisons will include fiberglass thickness, number of drywall layers, resilient channel spacing, and types of resilient sound clips. The general affect of each of those variables on acoustical performance will be shown. Several insights will also be shared from the acoustical supplier’s perspective on the UL listing experience.
The fire code and speech intelligibility.
Authors: Peppin Richard J.
Published: October 2013

The National Fire Code has provisions for speech intelligibility for annunciators. These requirements and their measurements will be discussed.
Phononic band gaps in periodically corrugated lithium niobate plate.
Authors: Ostrovskii Igor
Published: October 2013

A ZX-cut lithium niobate crystalline plate with a periodic corrugation is shown to have the band gaps in its spectrum of the plate acoustic waves. The corrugated plate is modeled numerically using finite element method. The depth of corrugations is 20% of the plate thickness along the Z-axis, and the corrugation period along the X-axis is taken from 0.3 to 1 mm for different model samples. The phase and group velocities of propagating acoustic modes will be affected significantly by the periodic change of plate thickness. The cutoff frequencies of higher-order modes will increase, and some new plate acoustic waves will appear. The periodic corrugations will cause the reflections and band gaps in the spectra of propagating modes. The strongest effects occur when the period of corrugations is equal to an integer number of half wavelengths of a mode. However, the distortions of the spectra do not appear in the spectrum if only 10% of the plate length is corrugated. One can achieve a complete band gap with certain corrugation periods and plate thicknesses. A periodically poled corrugated LiNbO3 is also considered. These acoustic properties of a phononic LiNbO3 crystal may be employed in a new generation of acoustic filters.
Large elastic softening in highly magnetostrictive Fe-based alloys.
Authors: LeBlanc Jared , Petculescu Gabriela , Wun-Fogle Marilyn , Restorff James , Lograsso Thomas , Clark Arthur , Hathaway Kristl
Published: October 2013

In order to practically exploit the large magnetostriction effects observed in Fe-based alloys, the magnetoelastic interactions in these materials have to be understood. Until now, Fe–Ga alloys have exhibited the largest magnetostriction in non-rare-earth alloys, but they also present a complex phase diagram, which does not allow a simple interpretation of magnetoelastic coupling at large Ga concentrations (above 20%). Fe–Ge alloys, which show an increase in the tetragonal magnetostriction but not as pronounced as in Fe–Ga, bring, however, a cleaner and more reproducible crystalline structure for the entire range of practical compositions. Measurements of elastic constants using resonant ultrasound spectroscopy in a saturating magnetic field and as a function of temperature for different compositions of the Fe–Ge alloys will be presented and contrasted to previously published Fe–Ga results. The addition of Ge to the structure of alpha-Fe softens the c′=(c11−c12)/2 shear modulus significantly. For example, only with 7 at. % Ge addition, c′ falls by 21% from the 48 GPa value of the pure Fe crystal.
Generalized acoustic cloaking theory.
Authors: Norris Andrew
Published: October 2013

An acoustic cloak is a region enclosing an object such that acoustic waves from all directions pass through and around the cloak as though the object was not present in the fluid. The object has zero scattering strength and is therefore acoustically invisible. Several researchers have proposed using fluids with anisotropic inertia for the cloaking material, but this has been shown by the author to require a cloak with infinite mass. An alternative framework is to use pentamodal materials, which guarantees finite mass and, under certain circumstances, isotropic inertia. The acoustic cloaking theory recently proposed by the author for acoustics is but one element in a class of cloaking theories for pentamodal materials. The main result is that pentamodal materials with anisotropic inertia form an invariant set of materials under arbitrary finite deformation and under the condition that the deformed material is cloaked. The general theory is explained using the language of finite deformations, common in continuum mechanics. The group properties follow by considering finite deformation in combination with gauge transformations. The talk will attempt to explain the meaning of pentamodal materials and show that the mathematics of transformation is related to simple physical requirements of transparency.
Using sound radiation to study collisions in granular media.
Authors: Riner Joshua , Regmi Chola , Petculescu Andi
Published: October 2013

An acoustic method to check the validity of Hertz's law and assess the actual collision force law in granular media is proposed. The technique uses a microphone to detect the sound produced by collisions between solid polypropylene balls. The impact is observed to produce an underpressure followed by an overpressure. It can be conjectured that the initial compression of the balls lowers the pressure, followed by an expansion which leads to a sharp pressure increase. The structure following the overpressure peak could be due to the bulk and surface waves produced in the spheres. There is a visible difference between the underpressure and overpressure peaks (of about 9%), which can indicate energy losses. The power spectrum has a dominant peak at ≈7 kHz, accompanied by several smaller peaks, some of which may be intermodulation products. [Work funded by the Louisiana Board of Regents.]
Modeling of transmission of shaped sonic booms into residential structures.
Authors: Sizov Natalia , Plotkin Kenneth , Hobbs Christopher
Published: October 2013

The indoor perception of shaped minimized sonic booms is a concern for the acceptability of overland supersonic flight. An investigation of the transmission of shaped booms into residential structures has been conducted. Two classical methods were used. The first is single degree of freedom analysis. The second is modal analysis, modeling a wall as a simply supported rectangular panel and the interior as a rectangular cavity. Time domain responses were computed for both methods. Both methods allowed arbitrary waveforms, and the modal model allows arbitrary wave incidence angle. Sound pressures inside a room and acceleration of the wall were calculated and compared to measured data collected during the NASA sonic boom tests conducted at the Edwards Air Force Base in 2007. The effects of wave signature parameters on transmission were studied to evaluate the advantages of various kinds of low boom shapes, and the influence of thickened shock structures. Future extension of this research will be to employ finite element modeling. [This work was funded by NASA Langley Research Center, Contract No. NNL07AD96T.]
Vibration and sound radiation from a rectangular panel with any boundary condition.
Authors: Zhang Xuefeng , Li Wen L.
Published: October 2013

This presentation is concerned with the vibroacoustic analysis of rectangular panels such as building walls, which may be isotropic or anisotropic in nature. A general analytical method is first described for modeling the vibration of a panel arbitrarily supported along each of its edges. The displacement field is analytically expressed as a two-dimensional Fourier cosine series supplemented with several one-dimensional series. Mathematically, such a series expansion is capable of representing and uniformly converging to any function (including the classical solution, if exists), which is adequately smooth over the solution domain. This series solution is exact in the sense that both the governing differential equation and the boundary conditions can be satisfied, on a pointwise basis, to any specified accuracy. Once the vibration field is determined, the resulting acoustic pressure and power radiation can be calculated in a simple and systematic manner. Numerical examples are given to demonstrate the vibroacoustic effects of the panel supporting conditions.
Interfacial and elastic contributions to the backscattering of a right circular cylinder: Experiments and interpretation.
Authors: La Follett Jon , Marston Philip L.
Published: October 2013

Synthetic aperture sonar (SAS) images of elastic targets near an interface contain features resulting from the interaction of incident and scattered sound with the interface in addition to those associated with the free-field dynamical response of the target. To improve the understanding of these features, a right circular aluminum cylinder was suspended in a water tank through an air interface and insonified at a grazing incidence. Monostatic SAS images were obtained by scanning the source (and receiver) along a horizontal line. Backscattering measurements were also made as the distance from the target to the interface was varied. Some of the features could be explained using a previously developed ray-based theory [K. Gipson and P. L. Marston, J. Acoust. Soc. Am. 106, 1673–1680 (1999);, 107, 112–117 (2000)]. Among these features were responses due to guided generalized Rayleigh waves such as meridional rays and helical rays. Also, ray path calculations for edge diffraction contributions (as a function of target-interface distance) were used to identify certain echoes in the SAS images. [Research supported by ONR.]
Measurement of diffracted pressure fields using an automated measurement system.
Authors: Simonaho Simo-Pekka , Lähivaara Timo
Published: October 2013

The theory of sound diffraction has been studied widely. Different modeling methods for sound diffraction have been proposed. Some of these modeling techniques are also used in the room acoustic modeling. In this study, diffracted pressure fields from a thin panel were measured. In the measurements, a loud-speaker was used as a sound source and diffraction from a thin panel was measured. The measurements were performed in small semianechoic chamber using a three-dimensional 3-D automated position system. This system consists of a 3-D position system, a data acquisition hardware, and a control unit. With this system, it is possible to measure diffracted pressure fields with high-spatial accuracy. In addition, numerical simulations are used in the modeling of sound diffraction from a thin edge. Finally, the simulated pressure fields are compared to the measured fields.
Development of subglottal quantal effects in young children.
Authors: Jung Youngsook , Lulich Steven M. , Stevens Kenneth N.
Published: October 2013

Quantal articulatory acoustic relations between formants and subglottal resonances have been shown to define several vowel and consonant distinctive features, including the vowel features (back) and (low). In particular, the F2 frequency of front vowels is higher than the second subglottal resonance (Sg2) but is lower than Sg2 for back vowels. Likewise for low vowels, F1 is higher than Sg1. Measurements of F1 and F2 for productions of the vowels /a/ and /ae/ were made on a number of occasions for several children in the age range 2.5–3.7 years. Measurements of Sg1 and Sg2 for each child were obtained from the locations of discontinuities in the F1 and F2 trajectories in diphthongs and in vowel-consonant transitions. At the earlier ages for these children, there was variability in the utterances, and the F1 and F2 values deviated from the expected relation. At the later age of 3 years and above, considerable agreement with the expected values of F1 and F2 in relation to the subglottal resonances was obtained. The transition from the expected quantal relation appears to occur in the age range between 2 and 3 years. [Work supported in part by NIH Grant R01-DC00075.]
F0 control in electrolarynx speech.
Authors: Saikachi Yoko , Stevens Kenneth , Hillman Robert
Published: October 2013

Over half of laryngectomy patients use an electrolarynx (EL) to communicate, but current EL devices produce a mechanical sound quality mainly due to the lack of natural F0 variation. In order to improve the sound quality of EL speech, the present study aimed to develop and evaluate an automatic F0 control scheme, where F0 in EL speech is covaried based on modulations in the rms amplitude of the EL speech signal. Declarative sentences ending with vowels produced by two male laryngectomy patients before and after the laryngectomy were used in order to develop procedures for controlling F0. The linear regression coefficients between F0 and rms amplitude in the normal speech were first determined and applied to the amplitude variation in EL speech to compute the F0 contour for the EL sentences. An analysis-by-synthesis approach was employed to modify the F0 contour of the EL speech as computed. Perceptual evaluation showed that the addition of amplitude-based F0 modulation resulted in EL speech that was judged to be more natural sounding than EL speech having constant F0, supporting the idea of using a simple linear relationship between amplitude and frequency to compute an F0 contour. [Work supported by NIH Grant No. R01DC006449.]
Advanced classification techniques for real-time signals in resource-constrained systems.
Authors: Peacock G. Scott , Barsic David , Llorens Ashley
Published: October 2013

Automated classification of situational awareness data collected by autonomous vehicles is currently an unmet need in many applications. Classification algorithms developed at JHU/APL extend large margin classification (LMC) machine learning techniques to solve domain-specific problems such as those found in unmanned undersea vehicles systems. Common classification issues for the described systems include the following: (1) Asymmetric binary class membership, that is, a small amount of a target signal must be distinguished in a very large collection of data; (2) no silver-bullet features, i.e., robust classification requires many weak features, are used to distinguish targets from other signals; and (3) limited processing resources. The JHU/APL solution uses existing LMC technology with modifications to solve specific domain issues: (1) addition of a penalty term to address class asymmetry, (2) an iterative training algorithm that yields a sparse solution optimized for a given computational footprint, and (3) featureless classification that requires minimal or no data reduction and can improve classification robustness of the algorithm and cut development costs. Use of these developed techniques is demonstrated using well studied open source data that are representative of that required for autonomous vehicle classification tasks.
Time-frequency variations of the bistatic scattering response of proud and buried elastic shells in shallow water: Implication for mine counter-measure sonar systems.
Authors: Anderson Shaun D. , Sabra Karim G. , Zakharia Manell E. , Kuperman William A. , Schmidt Henrik
Published: October 2013

For underwater sonar, time-frequency analysis has been shown to be a relevant tool for the detection and classification of man-made targets (shell). For instance, for traditional monostatic systems, a key energetic feature of spherical shell is the coincidence pattern, or midfrequency enhancement, that is created by the coherent addition of antisymmetric Lamb-waves propagating clockwise and counterclockwise around the shell. The development by the Navy of mine countermeasure sonar systems, using a network of autonomous systems in unmanned vehicles, provides a mean for bistatic measurements, and thus potentially bistatic enhancement for target detection. We have investigated the time-frequency variations of the bistatic scattering response of elastic shells. The influence of the medium parameters as well as the source-receiver configuration will be investigated in free space and then extended to the case of a shallow water waveguide. In particular, we studied the bistatic variations of the coincidence pattern for classification purposes. Finally, the design of a robust space-time-frequency bistatic sonar system will be discussed to enhance the target detection of shells with the use of multiple sensors.