bluuebunny/crossref_metadata_2025 huggingface dataset:
Spontaneous nasalization after glottal consonants in Thai: An rt-MRI investigation of rhinoglottophilia
Authors: Johnson Sarah E. , Sutton Brad , Liang Zhi-Pei
Published: November 2017

The affinity between glottal and nasal articulations (“rhinoglottophilia”) facilitates spontaneous nasalization. In Thai, low vowels nasalize after /h/ and to a lesser degree after glottal stop. Nasalization after /h/ may occur because breathiness and nasalization share high energy at low frequencies and a raised first harmonic. Glottal consonants generally may cause nasalization because aerodynamically they do not require a closed velopharyngeal port. We investigated whether Thai vowels after /h/ and glottal stop exhibit similar degrees of velopharyngeal opening (VPO) and compared these results with acoustic measures of nasalization / breathiness. We calculated nasalization / breathiness by the energy ratio of low and high harmonics; we measured VPO by processing oblique real-time magnetic resonance images of the velopharyngeal port. Four Thai speakers (two females, two males) produced relatively large VPO and high acoustic nasalization / breathiness after /h/. Female speakers nasalized vowels after glottal stop, though they produced overall less VPO and lower acoustic nasalization / breathiness when compared to vowels after /h/. In Thai, vowels after /h/ exhibit more physiological nasalization than vowels after glottal stop; furthermore, low VPO is associated with low acoustic nasalization / breathiness. We conclude VPO is primarily responsible for impressions of nasalization in this context.
Effect of beamwidth on detection of near-bottom targets with multibeam echosounders
Authors: de Moustier Christian
Published: November 2017

In multibeam echosounding, beamwidth and sidelobe levels constrain detection of echoes from near-bottom targets that are often masked by echoes from the bottom received in the mainlobe of individual beams or through their sidelobes. Acoustic backscatter data collected with multibeam echosounders from various manufacturers indicate that the customary half power point (−3 dB) metric for the angular width of individual beams underestimates the masking effects of bottom echoes. A better fit of the detected bottom echo trace is obtained with beamwidths estimated 10 dB below the maximum response of each beam. The corresponding beamwidths are roughly 66% larger at −10 dB than at −3 dB for a canonical sinc squared beam pattern. Therefore, using the manufacturers’ nominal −3 dB beamwidth specifications yields underestimates by the same percentage of the area ensonified by the pulse within a beam, and corresponding overestimates of the detected acoustic backscatter level used to infer target strength or bottom backscatter coefficients.
The research of a frequency-domain adaptive matched filter
Authors: Hui Juan
Published: November 2017

The most classical detector of active underwater acoustic is the matched filter (MF), which is the optimal processor under ideal conditions. Aiming at the problem of active sonar detection, we propose a frequency-domain adaptive matched filter (FDAMF) with the use of a frequency-domain adaptive line enhancer (ALE). The FDAMF is an improved MF. In the simulations in this paper, the signal to noise ratio (SNR) gain of the FDAMF is about 18.6 dB higher than that of the classical MF when the input SNR is −10 dB. In order to improve the performance of the FDAMF with a low input SNR, we propose a pre-processing method, which is called frequency-domain time reversal convolution and interference suppression (TRC-IS). Compared with the classical MF, the FDAMF combined with the TRC-IS method obtains higher SNR gain, a lower detection threshold, and a better receiver operating characteristic (ROC) in the simulations in this paper. The simulation results show that the FDAMF has higher processing gain and better detection performance than the classical MF under ideal conditions. The experimental results indicate that the FDAMF does improve the performance of the MF, and can adapt to actual interference in a way.
Intelligent active sonar via tuning of transmit waveform and detection threshold
Authors: Nelson Jill K. , Schoenecker Steven
Published: November 2017

We consider active sonar systems that translate high-level tasks to a set of parameter adaptations and arbitrate among competing demands, thereby incorporating cognitive processing in the system. We propose adopting the goal-driven autonomy (GDA) architecture presented in Klenk et al. [Computational Intelligence, May 2013] to realize intelligent active processing. Using the GDA architecture, the sonar system uses its observations to inform how system parameters are tuned to achieve a set of surveillance goals. In addition, the system is able to reason about its actions, identifying discrepancies between predicted and observed performance and modifying both parameters and goals accordingly. In this work, we focus on a tracking task and consider the transmit waveform and detection threshold as tunable parameters. We describe an active sonar system that tunes these two parameters based on observations of the physical environment and target characteristics, as well as current goals. The intelligent system uses its observations of the environment to generate estimates of target Doppler and of clutter density to tune waveform and detection threshold, respectively. Through simulation, we demonstrate the performance improvement achieved by the cognitive system when tracking a maneuvering target that is traveling through spatially non-uniform clutter.
Sound speed and attenuation in muddy sediments from low-frequency acoustic measurements
Authors: Wan Lin , Badiey Mohsen , Knobles D. P. , Wilson Preston S. , Eickmeier Justin
Published: November 2017

While there have been numerous theoretical and experimental studies on the properties of marine granular sands, there are significantly fewer studies on sediments classified as muds. The validity of geoacoustic models for muddy sediments has not been successfully tested due to the lack of inverted low-frequency sound speed and attenuation from acoustic measurements. The ONR-sponsored Seabed Characterization Experiment (SBCE), conducted in a mud patch on the New England continental shelf in the spring of 2017, provides an opportunity to make substantial improvements in understanding the physical mechanisms controlling sound propagation in muddy sediments. Acoustic signals (e.g., 31g explosive and combustive source signals) detonated at various ranges, depths and azimuths were measured in SBCE. This paper utilizes these measured signals to extract the acoustic normal mode characteristics including modal dispersive curve with Airy phase structure, modal amplitude, modal attenuation coefficient, and mode depth function. These normal mode characteristics are used in geo-acoustic inversion algorithms to estimate low-frequency sound speed and attenuation in muddy sediments as a function of frequency. The performance of different inversion methods using different normal mode characteristics is discussed. [Work supported by ONR Ocean Acoustics.]
Hybrid geoacoustic inversion method and its application to different sediments
Authors: Li Zhenglin , Zhang Renhe
Published: November 2017

Bottom acoustic parameters have large effects on sound propagation both in shallow water and in deep water with an incomplete sound channel. A hybrid geoacoustic inversion method is proposed to invert for sound speed, density and attenuation coefficient based on the facts that the bottom acoustic parameters have different sensitivities to sound field at different ranges. The hybrid inversion method is applied to inversion for bottom parameter with different sediments in the Yellow Sea, East China Sea, and South China Sea and verified by using the core sampling measurements. The relationships between the sediments types and the bottom acoustic parameters are given. The differences of the sediment acoustic parameters between sandy silty(or silty sand) and clay(or mud) sediment at low frequency are discussed in the end. [Work supported by the National Natural Science Foundation of China under Grant No. 10434012 and Grant No. 41561144006.]
Comparing performance of bottom-moored and unmanned surface vehicle towed passive acoustic monitoring platforms for sperm whale detection
Authors: Mahmud Sakib , Sidorovskaia Natalia , Li Kun , Pierpoint Chris , Tiemann Christopher , Mellinger David K.
Published: November 2017

Passive acoustic monitoring (PAM) is a more efficient method of monitoring the distribution and abundance of deep-diving cetaceans than conventional visual surveys. Many species produce identifiable acoustic signals during echolocation and communication which makes it possible to identify and classify based on their acoustical cues. Three different PAM platforms recorded data in overlapping time periods in the vicinity of the 2010 oil spill site: unmanned surface vehicle towed array, bottom-moored buoys, and Seaglider-mounted hydrophone. The detection rate of unmanned surface vehicle towed array and bottom-moored buoys were compared for their efficiency in detecting marine mammals. Detection events were obtained using independent detectors for each platform and then compared by feeding data through a common detector. The results of this study aid in the development of cost-efficient PAM methodology for mitigation and environmental impact assessment purposes. [This research was made possible by a grant from The Gulf of Mexico Research Initiative.]
Anechoic lesion detection in a strongly scattering medium: Application to pulmonary nodules
Authors: Mohanty Kaustav , Muller Marie M.
Published: November 2017

We present an imaging methodology to detect the presence of an anechoic lesion in a highly scattering medium consisting of spherical air scatterers. Classical imaging methods have failed to image such media. In the method presented here, the incoherent backscattered intensity is extracted and the linear growth of the diffusive halo is tracked. Sudden changes in this growth indicates the presence of a target. This algorithm combined with the algorithm of Winslow et al. on contour detection enables us to predict the presence and the location of such a lesion. This method has been developed to detect the presence of pulmonary nodules and ground glass opacities in the lung parenchyma. Using a 128-element linear array transducer operating at 5 MHz, experimental results were obtained from a sponge phantom with an air volume fraction of 50%, in which gelatin nodules of diameter 5 mm and 8 mm were implanted at depths of 15 mm and 20 mm, respectively. The diameter of the nodules could be predicted within an error margin of ±25%. FDTD simulations were also carried out with nodule sizes of 6mm and 11 mm, in media with 20% and 50% air volume fractions. The coordinates of the center of the lesion could be predicted within a tolerance of ±7%.
Quantitative ultrasound for the dynamic biomechanical analysis of tongue-food interface during oral processing: An in vitro study
Authors: Mantelet Mathieu , Souchon Isabelle , Panouillé Maud , Boué François , Restagno Frédéric , Mathieu Vincent
Published: November 2017

The development of non-invasive methods is critical for a better understanding of the biomechanical phenomena involved in the dynamic mechanisms of food texture perception during oral processing. The aim of the present study is to investigate in vitro the potential of a quantitative ultrasound device in order to monitor the mechanical properties of tongue-food interface during a compression. A tongue-palate bio-mimicking set-up was designed, consisting in a traction-compression machine equipped with tongue and palate phantoms. Gels and emulsion filled gels were considered as model foods for their wide ranges of texture properties. Finally, a 1 MHz ultrasonic transducer positioned under the tongue records in real-time the pulse-echo response of the tongue-food-palate system during a compression. The results put in evidence in vitro the potential of tongue-food interface reflexion coefficient to monitor the competitive and collaborative contributions (i) of the tongue-palate system (roughness, lubrication, and velocity) and (ii) of food properties (composition, structure, and rheology) on the mechanical properties of the tongue interface during occlusion cycles. The study paves the way for the use of quantitative ultrasound methods to monitor tongue-food-palate system during oral processing.
Assessment of dental implant stability: Coupling modeling and experimental approaches
Authors: Vayron Romain , Nguyen Vu-Hieu , Haiat Guillaume
Published: November 2017

Dental implants are widely used clinically but implant failures, which may have dramatic consequences, still occur and remain difficult to anticipate. Accurate measurements of implants biomechanical stability are of interest since they could be used to improve the surgical strategy. The aim of this work is to develop a medical device capable of estimating dental implant stability using quantitative ultrasound. To do so, our approach consists in coupling modeling and experimental methods. Firstly, an implant was initially completely inserted in the proximal part of a bovine humeral bone sample. The 10 MHz ultrasonic response of the implant is then measured and a quantitative indicator is derived. Then, the implant is unscrewed by 2π radians and the measurement was realized again. The value of indicator significantly increases as a function of the number of rotation. The results show that bone quantity in contact with the implant has a significant influence on its ultrasonic response. Secondly, a 3D finite element model is employed and the geometrical configuration is assumed to be axisymmetric. The numerical results show that the implant ultrasonic response changes significantly when a liquid layer is located at the implant interface.
Rapid and simple measurement of hypersonic wave velocity by Brillouin scattering with induced phonons
Authors: Shibagaki Yoshiaki , Takayanagi Shinji , Kawabe Masahiko , Yanagitani Takahiko , Suzuki Masashi , Matsukawa Mami
Published: November 2017

Brillouin scattering is a non-contact method to measure wave velocities in the GHz range. One problem of the Brillouin scattering technique is weak light scattering from thermal phonons, which results in the long measurement time and necessity of a complex tandem Fabry-Perot interferometer. To overcome this problem, we have proposed techniques to make use of induced strong coherent phonons from a high frequency transducer. In this study, we have tried to induce strong longitudinal coherent phonons by a ScAlN film transducer (composition of the film : Sc0.41Al0.59N), which has a high electromechanical coupling coefficient. The transducer was fabricated on the quartz sample and composed of the ScAlN film grown by an RF magnetron sputtering and electrodes. The transducer was deposited on one side of the sample. Due to the induced phonons, the scattered light became much stronger than those of thermal phonons and could be observed by a simple confocal Fabry-Perot interferometer. The measured frequency shift of the Brillouin scattering peak was equal to the excitation frequency of the ScAlN transducer (883 MHz). This technique enables easy, rapid and simple measurement of wave velocity in the GHz range, which can be applied for the 2D velocity imaging of the sample.
Resonant ultrasound spectroscopy measurement of elastic properties of SnSe
Authors: Karunarathne Ashoka , Gladden Josh R. , Priyadarshan Gautam , Wei Pai-Chun , Chen Yang-Yuan , Bhattacharya Sriparna , Rao Apparao M.
Published: November 2017

Resonant Ultrasound Spectroscopy (RUS) is a precise experimental approach for investigating the elastic properties of solid materials at different temperatures and hydrostatic pressures. In RUS, the elastic stiffness tensor of crystalline solids with different crystal structures are determined from their vibrational resonance spectra. A study of the mechanical properties of thermoelectric materials can provide insights to their high efficiency and low thermal conductivity. SnSe is a thermoelectric material which exhibits a high efficiency and low thermal conductivity due to its anharmonicity and low symmetric crystal structure. SnSe exhibits a structural phase transition from Pnma to Cnma at ∼800 K, and the single layered orthorhombic crystal structure of SnSe results in nine independent elastic constants. In this study, RUS was used to determine the temperature dependent elastic properties of polycrystalline SnSe through its phase transition temperature. Use of RUS technique to better understand the temperature dependent elastic properties of low symmetry crystals will be discussed. The elastic constants of single crystal SnSe calculated by RUS at room temperature are in agreement of within ∼35% of theoretical reported values.
Numerical investigation of metafluid behavior in pre-strained negative stiffness honeycombs
Authors: Goldsberry Benjamin M. , Haberman Michael R.
Published: November 2017

Negative stiffness honeycombs (NSH) are doubly periodic arrays of curved beams that have recently been shown to exhibit a reversible pseudo-plastic large deformation response and are therefore interesting candidates for impact isolation applications. The authors previously used finite element analysis to show that NSH exhibit three types of propagating modes described by (i) longitudinal, (ii) transverse, and (iii) rotational displacements with respect to the propagation direction. The phase and group velocities of each mode can be significantly altered by applying a uniaxial pre-strain imposed on the top and bottom boundaries of the NSH. The present work will show that the transverse and rotational mode phase speeds are significantly more sensitive to strain than the longitudinal modes for small but finite pre-strain levels. Consequently, for some pre-strain levels there exists a large frequency band where only longitudinal waves propagate. The pre-strained NSH therefore behaves as a pentamode metamaterial, or metafluid, and may represent a new type of structure to realize devices designed using transformation acoustics. The effect of the geometry and pre-strain on the existence and frequency range of unimodal propagation in pre-strained NSH will be investigated. [Work supported by NSF.]
Active vibration control by a tunable piezoelectric shunt metamaterial
Authors: Stearns Aaron J. , Beck Benjamin
Published: November 2017

Acoustic metamaterials are composite materials exhibiting effective properties and acoustic behavior not found in traditional materials. Primarily through periodic subwavelength resonant inclusions, acoustic metamaterials can enable steering, cloaking, lensing, and frequency band control of acoustic waves. However, a common drawback of acoustic metamaterials is that effectiveness is limited to narrow frequency bands. Thus, investigation of practical active and adaptable acoustic metamaterials is valuable in achieving wider operation frequency bands. Here, a metamaterial consisting of active tunable piezoelectric shunts is investigated numerically and experimentally from the unit cell level. A physical model of the unit cell is developed using the finite element method. From the finite element model, the wave finite element method is applied to compute the dispersion and forced response of the periodic structure. It is demonstrated that the shunts introduce an additional degree of freedom by which adaptable bending wave attenuation can be accomplished. Since the periodic shunts are only effective at certain frequency bands, a known optimization method is implemented to tune the shunts. Additionally, a new optimization scheme is compared to the existing scheme found in literature.
Uniformity of inherent vowel duration across speakers of American English
Authors: Wilson Colin , Chodroff Eleanor
Published: November 2017

Vowel duration is determined by a number of factors in American English (e.g., Klatt, 1976), including the tense vs. lax distinction (e.g., /i/-/ɪ/, /u/-/ʊ/) and the relation between duration and vowel height (e.g., Lehiste, 1970). A large body of research has identified segment-internal factors in data averaged over many speakers (e.g., Crystal and House, 1988; Hillenbrand et al., 1995), but few studies have investigated the inherent vowel duration patterns of individuals (cf. House, 1961). Stressed vowel productions (>2 million tokens) were identified by forced alignment in connected speech recordings of 390 speakers (209 female) from the Mixer 6 corpus (Chodroff et al., 2016). For each speaker, mean durations of ten stressed vowels (/i ɪ e ɛ æ a ʌ o ʊ u/) were calculated after outlier exclusion. The resulting duration patterns were strongly correlated across pairs of speakers (Pearson r: mean = 0.936, 95% CI [0.935, 0.936], range [0.559, 0.999]), and PCA identified a single component, plausibly indexing global speaking rate, that accounted for more than 82% of the variance. These results establish that inherent vowel duration is highly uniform across speakers, a type of structured phonetic variation that has implications for models of perceptual adaptation.
Determining the place of articulation of Arabic voiceless dorsal fricatives
Authors: Charles Sherman D. , Alfaifi Abdullah , Abo-Mokh Noor , Robinson Sarah , de Jong Kenneth
Published: November 2017

Previous, mostly impressionistic, examinations of Arabic varieties provide varied descriptions of the dorsal fricative /χ/ place of articulation, ranging from velar to uvular. While some descriptions attribute this variation to dialectal differences, descriptions of the same dialect also vary. 3D ultrasound data were collected from six native speakers of different dialects of Arabic, one each from Syria, Palestine, Faifi (in Saudi Arabia), Egypt, Algeria, and Morocco. Apart from the dorsal fricatives, the corpus included productions of palatal, pharyngeal, and contrasting velar and uvular stops to provide comparative standards for various points of articulation. The Syrian, speaker showed very similar articulations for /χ/ with uvular stops, while the other speakers variably showed a more anterior articulation between the velar and uvular stops. The most anterior articulations were apparent in the Moroccan and Algerian speakers, giving some suggestion of a dialectal difference; however, point of articulation of the dorsal fricative was variable for most of the speakers and not obviously restricted by dialect. The effect of these articulatory observations on the acoustic noise spectra are ongoing.
Dialect contact and word-specific phonetics: North Koreans in Seoul
Authors: Kang Yoonjnung , Yun Suyeon
Published: November 2017

This study examines the speech of North Korean refugees who currently reside in Seoul. We investigate (a) how the North Korean speakers’ stops are affected by contact with Seoul Korean and (b) whether words only commonly used in the North and words newly acquired in the South are realized differently. The data were collected from 35 Hamkyeoung speakers, balanced for age (born before vs. after 1975) and time since arrival in Seoul (0–3 vs. 3–15 years). Twenty Seoul speakers also participated as a comparison group. Participants produced 78 stop-initial words with two repetitions, evenly divided into North vs. South lists, balanced for laryngeal feature, place of articulation, and the following vowel height across the lists. The results show that in line with previous literature, Hamkyeoung aspirated stops are longer in VOT than Seoul stops and Hamkyeoung lenis stops are shorter in VOT than Seoul stops. We found evidence for contact-induced phonetic drift for aspirated stops, but not for lenis stops—earlier arrivals produce aspirated stops with a shorter VOT than recent arrivals. We found no evidence of word-specific phonetic representation and stops were produced with a comparable VOT value regardless of their Northern vs. Southern origin.
Practicing English medical word pronunciation with a communication robot and a tablet by Japanese medical students
Authors: Sakamoto Yoko , Sakata Nobuhiro
Published: November 2017

The aim of this study was to investigate which tool can be more effective way to practice English medical word pronunciation for Japanese medical students: a communication robot or a tablet. The subjects were 8 Japanese medical freshman students. The target words were 10 medical words related to an infectious disease. In the training, the subjects learned the meaning of the word in Japanese and then they practiced the pronunciation in English. Four subjects followed the order; Pretest → Robot → Posttest1 → Tablet → Posttest 2, while the remaining 4 subjects were counterbalanced; Pretest → Tablet → Posttest 1 → Robot → Posttest 2. All subjects answered the questionnaire after Posttest 2. The process was videorecorded and the waveform was analyzed. The results showed that the postures and voices of the subjects were better with a communication robot than with a tablet. The pronunciation practiced with a communication robot had improved with a fewer trial. The subjects wrote in the questionnaire that they could practice pronunciation with a communication robot aiming to be able to talk with a person in the future. Thus, compared to a tablet, a communication robot can be an effective tool to practice English medical words.
Novel imaging tools for supporting the teaching of singing and spoken performance
Authors: Blaylock Reed , Narayanan Shrikanth S.
Published: November 2017

Recently, singers and singing instructors have begun to use real-time magnetic resonance imaging (rtMRI) videos of speech and singing movements as a pedagogical tool. Singers use videos of vocal tract movements to learn about the movements of speech, and are then able to contrast those movements with their ideal singing productions. These validated images can now replace the previous “practice-of-speculation” regarding the articulatory postures desirable during singing. While rtMR videos are most often used by professional instructors and aspiring-professional singers, these videos may soon commonly be used to assist amateur choruses as well, which often struggle to produce unified vowel qualities. Beatboxing is a related and unexplored pedagogical domain, yet beatboxing was one of the earliest spoken performance styles acquired at USC with real-time MRI. These videos, together with USC’s publicly available inventory of rtMR videos demonstrating the sounds of the world’s languages, provide a rich resource for the extreme and varied percussive sounds used by beatboxers. In sum, students of singing and spoken language performance have a brand new asset available to them in the form of dynamic real-time MR videos of the moving vocal tract. [NIH R01DC007124.]
Detection performance analysis of product processing of colinear arrays
Authors: Adhikari Kaushallya , Buck John R.
Published: November 2017

Non-uniform linear arrays (NULAs) often achieve better resolution than standard uniform linear arrays (ULAs) with equal numbers of sensors. However, conventional beamforming (CBF) of an NULA received signal leads to the same detection statistic PDF as a ULA with the equal number of sensors, undercutting NULA's improved resolution. Nested and coprime arrays partition an NULA into two subarrays and multiply the subarrays' CBF outputs. This research compares this product processor's detection performance against a CBF detector with an equal number of sensors for a narrowband Gaussian signal in spatially white additive Gaussian noise. The product processor's detection PDF is a scaled product of the detection statistic with modified Bessel functions. Receiver operation characteristics (ROC) curves illustrate that the product processor's performance is inferior to the CBF detector with an equal number of sensors. The detection performance of a product processor matches the CBF detector only for high SNRs and large numbers of sensors. However, in the presence of interferers, the product processor for coprime arrays can outperform both the CBF detector and product processing nested arrays with an equal number of sensors. [Work supported by ONR.]
Small aperture acoustic methods to locate transients
Authors: Scanlon Michael V.
Published: November 2017

Acoustic microphone arrays have been used in battlefield environments to detect and locate continuous wave targets like helicopters and ground vehicles, and for transient events like gunshots, mortars, rockets and explosions. Depending on the application, source bandwidth, propagation distance, and required localization accuracy, these arrays can vary their sensor separation greatly. Unattended ground sensors, manned- and unmanned-platforms, and Soldier-worn systems can all benefit from very small apertures if performance can be maintained. A commercially available acoustic particle velocity sensor, approximately one-half an inch in diameter, showed good transient localization at a field experiment. Data will also be presented from a small cluster-array of cardioid microphones.
Extrapolated open spherical microphone arrays beamforming for acoustic source localization
Authors: Yang Boquan , Shi Shengguo , Li Ying , Zhang Lanyue , Wang Chao
Published: November 2017

Spherical microphone arrays have become a particular tool for analyzing the spatial sound field, especially in source localization and identification. Spherical Harmonic Beamforming (SHB) is a fundamental algorithm with the spherical microphone arrays in aeroacoustics. However it presents some intrinsic limitations, specific poor resolution and sidelobe suppression capability. This paper aims to overcoming this limitations by employing Functional Beamforming and Beamforming Regularization Matrix. Functional beamforming has a narrower the mainlobe width and lower sidelobes by increasing the order of matrix functions. To improve the performance of algorithm at low frequency, this paper uses an extrapolated spherical arrays that is a larger radius of the spherical arrays through the Beamforming Regularization Matrix algorithm which can improve the spatial resolution. The results of numerical simulations and experiments show that the proposed method can remarkably suppress beamforming sidelobes, improve dynamic range of the system，and obtain a higher array gain, which leads to the accurate identification the location of sound sources.
Bayesian geoacoustic inversion of seabed reflection data at the New England mud patch
Authors: Belcourt Josée , Dosso Stan E. , Holland Charles W. , Dettmer Jan
Published: November 2017

This paper presents nonlinear Bayesian inversion of wide-angle seabed reflection-coefficient data for fine-grained/cohesive sediments recorded in the ONR Seabed Characterization Experiment at the New England mud patch. In particular, the inversion is applied to high-resolution broadband reflectivity data from a site with a ∼11-m thick mud layer. Trans-dimensional inversion, sampling over an unknown number of seabed layers, and spherical-wave reflection modeling are employed. The inversion provides maximum a posteriori parameter estimates with uncertainties quantified in terms of marginal posterior probability profiles for sound speed, density, and attenuation as a function of depth in the sediment. [The research was funded by the Office of Naval Research, Ocean Acoustics Program, and the Canadian Department of National Defence.]
Analyses of crowd-sourced sound levels, logged from more than 2250 restaurants and bars in New York City
Authors: Farber Gregory , Wang Lily M.
Published: November 2017

Media reports in the United States and the United Kingdom have reported increasingly high sound levels in restaurants and bars over the past ten years, but accurate sound measurements are lacking. The Zagat survey found noise to be the second most common complaint among diners, barely behind poor service. This paper presents sound level measurements from more than 2250 restaurants and bars in New York City, using the novel SoundPrint smartphone app. The average sound level was found to be 78 dBA in restaurants and 81 dBA in bars. These sound levels do not allow ready conversation and pose a auditory health danger for noise-induced hearing loss and other non-auditory health issues. The reported sound levels by venue managers generally underestimated actual sound levels. Of interest are the findings that venues in certain neighborhoods and also of certain types of cuisine tend to be louder or quieter than others. The sound level values measured by the SoundPrint app have been tested against class 1 sound level meters and found to be reasonably close (within 1–2 dB). This report is a proof-of-concept study of crowd-sourced sound measurements, which can provide valuable data for the general public and health officials.
A comparative study of sound environment of restaurants in Singapore, Macao, and Hong Kong
Authors: Lau Siu Kit , To W M , Chung Andy
Published: November 2017

Some of the key elements affecting the indoor sonic environment of a restaurant depend on its size, room configuration, architecture features, and occupancy rate. Whether the languages of people speak in the same venue or a combination of theirs have an impact remains unsure. Surveys have been conducted in three tourist cities, namely, Singapore, Macao, and Hong Kong, to collect the audio, visual, and quantitative data of the indoor sound environment of selected restaurants. This paper presents the results and comparative analytics of the surveys.
Behavioral and electrophysiological assessment of hearing in the Japanese quail (Coturnix japonica)
Authors: Strawn Sarah N. , Hill Evan M.
Published: November 2017

Presented are the behavioral audiogram and auditory brainstem response (ABR) recordings from the Japanese quail (Coturnix japonica). This study was particularly interested in the sensitivity of this species to infrasound (i.e., frequencies below 20 Hz). Previous histological research found that the basilar papilla of gallinaceous species tends to be specifically tuned to frequencies below 1 kHz. Consistent with this finding, previous behavioral tests of chickens demonstrated exceptional sensitivity to low-frequency sounds, especially infrasound. The results of this study show that the Japanese quail has a sensitivity to 16 Hz that is equivalent to that of humans, and thus their infrasound sensitivity is far less than that of the chicken. The ABR recordings did not match the sensitivity or frequency range of the behavioral audiogram, though they provided a reasonable estimate of the high-frequency limit of the animal’s hearing range and frequency of best sensitivity. These findings are consistent with histological evaluations of the inner-ear physiology of gallinaceous birds that suggest the low-frequency end of the Japanese quail’s hearing range is shifted slightly away from that of other birds of this order, though they would still possess good sensitivity below 1 kHz.
An information-theoretic approach to choosing spectrogram resolutions for analyzing different biological and musical sounds
Authors: Taft Benjamin N.
Published: November 2017

The great diversity and abundance of animal sounds have been portrayed by spectrograms for more than 75 years. Until recently, the time- and frequency-resolution of spectrograms was dictated by hardware limitations such as the number of filter banks in a spectrograph, the sample rate of a digitizer, or the storage capacity of a computer's memory. Improvements in these technologies, especially in the sample rate, has expanded the range of practical time- and frequency-resolutions that spectrograms can display, even if it is still necessarily caught in a tradeoff between resolving temporal or frequency details at each given sample rate. The region of this tradeoff, however, may now actually exceed the time- or frequency-resolving ability of the auditory systems of the animals that emit and perceive biological sounds. Animals are also bound by the fundamental time versus frequency tradeoff. Therefore, if we can measure the best time- and frequency-resolution to analyze a signal, we can both increase analytical efficiency and gain insight into the perceptual abilities of the receivers of the signal. An information metric is proposed for determining the optimal time- and frequency-resolution to analyze a sound. It consists of the frequency excursion of the sound across time windows, divided by the autocorrelation among adjacent spectrogram time windows. The metric is evaluated by applying it to several species of bird song, as well as whale calls, human speech, and musical notes,
Examination of behavioral response of wild river herring to sonar signals using acoustic telemetry
Authors: Iafrate Joseph , Watwood Stephanie L. , Kutcher Jessica , Dossot Georges
Published: November 2017

The potential effect of high-intensity noise and disturbance to fish populations is of growing concern. Adult river herring were exposed to mid-frequency (1–10 kHz) sonar signals to assess behavioral response in their natural environment. In this case study, acoustic telemetry was employed to measure fine scale movement of free-ranging river herring released in Dodge Pond, Connecticut, in response to a controlled sound exposure experiment. Alewife (Alosa pseudoharengus) was selected as the target species due to natural occurrence in the study area and documented hearing specializations in this species. An acoustic telemetry array was used to examine movement, spatial distribution, and schooling behavior of the fish before, during, and after exposure to mid-frequency sonar or similar sonar signals. Movement parameters examined include directional response, distance moved, swim speed, and distribution of the school. The sound field was mapped to assess received levels including both sound pressure level (SPL) and particle velocity within full extent of the telemetry array. Preliminary results will be presented including novel methods for gastric tagging, baseline behavior, performance of the array, and measurements supporting sound field mapping.
Two ultrasound longitudinal waves in cancellous bone acquired using a fast decomposition method with a phase rotation parameter for bone quality assessment
Authors: Taki Hirofumi , Nagatani Yoshiki , Matsukawa Mami , Izumi Shin-Ichi
Published: November 2017

Ultrasound signal passing through cancellous bone consists of two longitudinal waves: fast and slow waves. Accurate decomposition of the fast and slow waves is supposed to be highly beneficial in order to determine the characteristics of cancellous bone. We applied a fast decomposition method using adaptive beamforming technique with a phase rotation parameter to ultrasound signals that passed through bone specimens with various bone volume to total volume (BV/TV) ratios in a simulation study. The decomposition method accurately characterized the two waves with the normalized residual intensity of less than −19.5 dB when the specimen thickness ranged from 4 to 7 mm and the BV/TV ratio was from 0.144 to 0.226. The ratio of the peak envelope amplitude of the fast wave to that of slow wave increased monotonically as BV/TV ratio increased. The result also indicates a strong relationship between the phase rotation value and BV/TV ratio, where the variation of the phase rotation value increased as specimen thickness increased. These findings show that the decomposition method using adaptive beamforming technique with a phase rotation parameter has the high potential in estimating the BV/TV ratio in cancellous bone.
Development of an S3/SC1 standard for auditory evoked potential hearing tests in toothed whales
Authors: Houser Dorian S.
Published: November 2017

The National Marine Fisheries service regulates the impact of anthropogenic ocean noise to marine mammals. Other government and commercial groups that produce ocean noise are subject to regulation. Both groups desire greater knowledge of hearing in marine mammals to better predict, mitigate, and regulate noise exposure. Auditory evoked potential (AEP) hearing tests have become a primary method by which hearing tests are performed in toothed whales (e.g., dolphins, porpoises). The synthesis of AEP data to address noise impacts to marine mammals is limited, in part, because of the variability between AEP thresholds measured by different researchers and laboratories using different methodologies. Methodological differences exist for AEP detection, threshold estimation, calibration, and stimulus delivery. Threshold variability could be reduced through standardization of AEP hearing test methods, which is desired by regulatory agencies and sound producers. An S3/SC1 standard for AEP hearing test methods in toothed whales has been initiated to address this need. The draft standard will be submitted to ANSI for consideration by the end of 2017. Adoption of the standard internationally would further improve threshold comparability by ensuring researchers globally utilize the same methods. The process should increase AEP data reliability for purposes of addressing ocean noise issues.
An acoustical study focused on the effects of guitar soundboard material on sound propagation
Authors: Saccaggi Guido , Capozella Josh , Kuebler Derek , Turo Diego , Vignola Joseph F.
Published: November 2017

This presentation describes a student project that aims to study the effect of a guitar top’s material and bracing design on measurable parameters such as radiated sound power and spectrum. To illustrate, two identical, classical guitars were purchased, and the soundboards were replaced. The top of one guitar was replaced with a soundboard composed of two different woods and the other with a carbon fiber composite. Mahogany and spruce were chosen as the two woods, as mahogany is purported to enhance lower notes and spruce to enhance higher notes. Carbon fiber was picked to maximize flexural rigidity of the top. Performances of the two guitars were characterized by measuring the acoustic pressure at a fixed distance from the guitar. Additionally, the vertical acceleration of specific locations of the top was also measured as well as the strain in the pick to make a fair comparison between the sounds radiated by both guitars. Sound recordings were analyzed with time-domain, frequency spectra, and to compare the performance of the two guitars
A study on the sound investigation of wooden gong rock
Authors: Kim Bong Young , Bae Myungjin
Published: November 2017

In Korea, there is a rock with a wooden gong sound. It is the wooden gong rock of Pyochungsa Temple in Miryang, Gyeongsangnam-do, and drum rock of Palgongsan Mountain in Daegu. The wooden gong is one of the Buddhist ceremonial tools that make a sound by knocking an empty tree. In this paper, we will investigate which sound component of wooden gong rock and drum rock as a wooden gong sound through sound analysis. The wooden gong resonates at about 600 Hz when tapped and continues to sound for about 0.1 second. However, most stones and rocks have a sound duration of less than 0.3 seconds without any resonance. Pyochungsa Temple's Wooden gong rock resonates at about 600 Hz and shows a duration of 0.6 to 0.9 seconds, depending on the knocking position and strength. Palgongsan Mountain's Drum rock resonates at about 400 Hz and has a duration of about 0.5 seconds. We conducted a MOS test on 30 people to see how much sound like a wooden sound for each sound. The results were as follows: wooden gong 4.5, wooden gong rock 4.1, drum rock 3.4, and common stone 2.0. Thus, the sound component of Pyochungsa Temple's wooden gong rock is closest to the wooden gong sound, so it sounds like a wooden gong sound. Wooden gong rock's wooden gong sound inspires Buddhist believers and tourists with Buddhist aspiration and patriotic loyalty. By investigating the sounds of these cultural heritages, the value and meaning of cultural heritage can be reexamined.
Effects of residual masker, spectral resolution, and low frequency cues on the perception of ideal binary-masked speech
Authors: Montazeri Vahid , Assmann Peter F.
Published: November 2017

This study investigated the intelligibility of ideal binary-masked (IdBM) stimuli under conditions with limited spectral resolution. In experiment 1, we used different IdBM local thresholds, which retain different amounts of residual masker and target information in the IdBM-stimuli. The stimuli were presented to 30 normal hearing listeners. The results indicated that, with a 6- or 12-channel tone-vocoder, the presence of residual masker in the IdBM-stimuli limits the intelligibility scores, thus preventing IdBM processing from achieving an ideal segregation of target from masker. In experiment 2, we investigated whether introduction of low frequency target information to the tone-vocoded IdBM-stimuli improves the intelligibility scores. Twenty normal hearing listeners participated in this experiment. The results indicated that in contrast to target F0 cues, inclusion of low-pass filtered target information (cutoff = 300 Hz) helped listeners segregate the target from the masker, thus improving the intelligibility of the IdBM-stimuli. These results argue against F0 as a segregation cue in electroacoustic conditions and suggest that target F0 cues do not provide benefits beyond those provided by IdBM.
Spectrum contrast sharpening by lateral suppression: Comb-filtered noise test
Authors: Supin Alexander , Nechaev Dmitry , Popov Vladimir , Sysueva Evgeniya
Published: November 2017

Spectrum contrast thresholds were measured in normal listeners using comb-filtered signals. The signal spectrum contained 0.075-oct wide ripples. Spectrum contrast varied from 0 (no ripple on the pedestal) to 1 (zero spectrum level between the ripples). Spectrum contrast thresholds were measured at ripple densities from 1 to 10 oct-1 using a two-alternative forced-choice adaptive procedure. The lowest spectrum contrast thresholds of less than 0.1 appeared at a ripple density of 4 oct-1. At lower ripple density down to 1 ocn-1, thresholds increase up to 0.2. At ripple densities above 4 oct-1, thresholds steeply increased up to 1.0 at densities of 8 to 10 oct-1. In agreement with the excitation-pattern model, threshold increase at high ripple densities may be explained by across-frequency integration in critical bands. However, threshold increase at low ripple densities cannot be explained by a simple critical-band model. The lowest spectrum contrast thresholds at a certain inter-ripple interval indicate the presence of lateral suppression zones in equivalent filter forms. According to this interpretation, the results demonstrate sharpening of spectral contrast due to lateral suppression. The lateral suppression zones may reflect either cochlear lateral suppression, or lateral inhibition in neuronal centers, or both. [Work supported by Russian Science Foundation.]
Pure-tone lateralization revisited
Authors: Völk Florian , Encke Jörg , Kreh Jasmin , Hemmert Werner
Published: November 2017

In certain conditions, especially with diotic headphone presentation, hearing sensations are located inside the head. Dichotic headphone presentation can result in lateralization: delaying one of the headphone input signals or reducing its amplitude typically pushes the hearing sensation inside the head toward the contralateral ear. Systematic connections between physical stimulus parameters and hearing-sensation positions provide insight into auditory-localization mechanisms and are helpful in designing and evaluating models thereof. However, typical paradigms of addressing lateral displacement, magnitude estimation or pointing, may suffer from response biases. This study aims at evaluating the suitability of a two-alternative forced choice paradigm: 15 normal-hearing subjects were asked to indicate, by pushing one of two buttons, whether the hearing sensation associated with a pure interaural phase or amplitude difference occurred “left or right,” without any reference or further instructions. Posing a notably simple task without internal mapping, this procedure appears advantageous regarding response biases. The results indicate a high intra-individual reproducibility and plausible inter-individual agreement. None of the participants encountered or reported difficulties using the inherently assumed “internal center” in their decision process. The data suggest the existence of an inter-individually similar decision criterion. Descriptively speaking, the results support the existence of a similar lateralization midpoint.