bluuebunny/crossref_metadata_2025 huggingface dataset:
Dynamic binaural-correlation processing in rats' inferior colliculus, medial geniculate body, and primary auditory cortex
Authors: Wang Qian , Cao Shuyang , Li Jingyu , Wu Xihong , Li Liang
Published: April 2012

Interaural correlation processing is critical for grouping and segregating auditory streams under reverberant environments with multiple sources. Although detection of dynamic changes in interaural correlation has been extensively studied in the field of psychoacoustics, the underlying neural mechanism remains largely unknown. In this study, frequency-following responses (FFRs) to narrow-band noises were measured at various levels of the auditory system in rats, including the inferior colliculus (IC), ventral division of the medial geniculate body (MGB), and primary auditory cortex (A1). The results of Experiment 1 show that FFRs recorded in the IC were affected by both interaural correlation and the interaural time difference (ITD). Moreover, results of Experiment 2 show that a break in interaural correlation (BIC) could elicit marked FFRs in each of the three central auditory structures, and the BIC-induced FFRs were significantly affected by the ITD. The results suggest that the rat's central auditory system is able to resolve and compare fast changes in fine-structure details of arbitrary noises presented at the two ears.
Associative visuoauditory memory in the auditory cortex
Authors: He Jufang , Chen Xi , Guo Yiping , Liao Zhengli , Li Xinjian , Wang Haitao , Li Xiao
Published: April 2012

This paper presents direct evidences of the establishment of associative memory traces in the rat auditory cortex and the participation of the entorhinal cortex in the establishment and retrieval of these memory traces. We produced an association between cortical electrical activation and a visual stimulus with classical conditioning. The memory traces were physiologically visualized from auditory neuronal responses to the visual stimulus after conditioning and behaviorally confirmed with a memory recall experiment. Formation of new associative memory in the auditory cortex with classical conditioning was bilaterally blocked when the entorhinal cortex was unilaterally temporarily inactivated, but returned if the entorhinal cortex was not inactivated. Retrieval of the established associative memory in the ipsilateral neocortex was affected by the inactivation of the unilateral entorhinal cortex, while that in the contralateral neocortex was not affected, thus suggesting a less dependence of the hippocampal system in the retrieval than in the formation of associative memory. Supported by Hong Kong Research Grant Council (PolyU 9/CRF/09)
The study of time-frequency analysis the nocturnal snoring signal based on the wavelet transform
Authors: Yinhong Zhang , Quanlu Li , Jing Wu
Published: April 2012

This paper presents a time-frequency analysis method for non-stationary snoring signal that based on the discrete wavelet transform. The snoring is an important characters of upper airway obstruction and a typical inspiratory sound appearing during sleep. The severe snoring sound leads to the Obstructive Sleep Apnea Syndrome during persistent ventilatory movements and it can result in cessation of breathing. The resulting experimental shows that the characters of different time-frequency domain of the snoring signal and offers value for analyzing the temporal feature of snoring sound in health medical treatment. It is an interesting application of the wavelet transform theory in the medical field.
Improvement on coherent signal-subspace method using several reference frequencies
Authors: Feng Dahang , Bao Ming , Guan Luyang , Tong Jianfei , Li Xiaodong
Published: April 2012

An improved coherent signal-subspace method is proposed using several reference frequencies for wideband direction-of-arrival (DOA) estimation. In this proposed method, the whole bandwidth of the received signal is divided into several parts, then a reference frequency is selected from each part for the coherent signal-subspace method to estimate the DOAs of wideband sources separately, and the results from all frequency parts are averaged to obtain a final estimate. Compared with the conventional coherent signal-subspace method, the proposed method achieves higher resolution and smaller root mean square error, especially when the bandwidth of the source is large. The performance of the proposed method is demonstrated and analyzed through the computer simulations.
Autocorrelation-function-based estimation approach and variability of waveguide invariant in fluctuated shallow water
Authors: Shihong Zhou , Li He , Yun Ren , Renhe Zhang
Published: April 2012

Waveguide invariant, which describes the broadband acoustic field interference striations in underwater acoustic spectrograms due to multipath phenomena of sound propagation, is beneficial to be applied to temporal and spatial array signal processing specially for large-aperture horizontal line array, etc. However, the dependence of waveguide invariant on fluctuated water-column environment due to internal waves or internal tides is often complicated and shows different interference patterns, which influents the performance of temporal and spatial array signal processing. This presentation focuses on variability of waveguide invariant in fluctuated shallow water environment. One novel estimation approach of waveguide invariant based on phase-shift-compensation of autocorrelation functions at two hydrophones with horizontal range separation is presented. The experimental airgun-emitted pulse data acquired in iso-speed shallow water environment is used to verify the estimation approach. Based on it, the variability of waveguide invariant in fluctuated shallow water with internal wave effects are analyzed using long-term observed LFM signals obtained by one sea-floor located horizontal-line-array and one fixed sound source. The contribution of low- and higher- order filtered modes to interference patterns is given for explaining the mechanism of mode interference. Some interesting experimental results are shown.
Acoustical monitoring of the second mode internal solitary wave on oceanic shelf
Authors: Lunkov Andrey , Hwung Hwung-Hweng , Petnikov Valeriy , Wang Yu-Huai , Yang Ray-Yeng
Published: April 2012

The possibility of monitoring second gravitational mode internal solitons using interference pattern frequency shifts is discussed. The investigation is carried out for the shelf of the northern South China Sea near the Dongsha Atoll by means of numerical modeling. We used the data of the in-situ internal solitons measurements in this area. The “vertical modes and horizontal rays” approach is implemented to calculate the low frequency sound fields in the 3d environment. Stationary acoustic path is oriented at the right angle to the preferred internal wave propagation direction. A sound source and receivers are deployed at the sea bottom. Sound receivers are located at the different ranges where horizontal refraction is pronounced, and where it is insignificant. Numerical experiments demonstrate that some of acoustic waveguide modes are focused, and others are defocused in the horizontal plane when the second mode soliton propagates across the acoustic path. It is shown that the second mode internal solitary wave parameters can be successfully reconstructed from the frequency shifts in the spectrum of received signals only if horizontal refraction effects are weak. [Work supported by Russian Foundation for Basic Research and National Science Council of Taiwan # 10-02-92005]
Comparison of automated and aural/visual techniques to classify humpback whale (Megaptera novaeangliae), song units
Authors: Copeland Adrienne M. , Au Whitlow W. L. , Lammers Marc O. , Pack Adam A. , Oswald Julie N. , Chen Jessica
Published: April 2012

Humpback whale song research has focused on analyzing the full song structure rarely describing individual song units. Even less progress has been made in automatically distinguishing and classifying these individual units. Two different techniques were employed to study their call units, visual/aural and automated/statistical. Humpback whale songs were recorded in the Hawaiian Islands both remotely with an autonomous acoustic recorder and by a snorkeler with a portable digital tape recorder. Humpback whale song units collected by the autonomous acoustic recorders were aurally separated into 23 distinct units in a companion study. Song units collected by a snorkeler using the portable recorder off Maui were analyzed using a specialized Matlab script that defined 48 frequency and temporal parameters for each unit. From the 48 parameters, the units were separated into distinct categories using a multivariate categorical analysis. The distinct units were compared between the different techniques to gage if automated methods could be used in future humpback whale studies. After this comparison was made, a principal component analysis (PCA) determined which of the aforementioned 48 parameters were important in statistically distinguishing between the distinct units furthering our understanding of frequency and temporal importance in categorizing song structure.
Ultrasonic properties of fast and slow longitudinal waves propagating in the cancellous bone
Authors: Fujita Fuminori , Yamashita Keisuke , Mizuno Katsunori , Matsukawa Mami , Otani Takahiko
Published: April 2012

Longitudinal wave in cancellous bone separates into fast and slow waves depending on the alignment of trabeculae. Here, the fast wave mainly propagates in trabeculae, whereas slow wave propagates in the soft tissue (bone marrow). Because these two waves usually overlap, the evaluation of each wave has still remained difficult. In this study, then, we have tried to evaluate the wave properties (attenuation and velocity), making use of the plane wave in an acoustic tube. 3-D image of the bone specimen was obtained by X-ray micro CT. In an acoustic tube, a cancellous bone specimen was set between home-made PVDF transducers. A function generator delivered a single sinusoidal signal in the range of 0.5 to 1.5 MHz to the transmitter. By filing a part of bone specimen away, we have tried to obtain the attenuation and velocity of the specimen. The two wave phenomenon clearly occurred in our specimen. In some trabecular bones of big animals, the wave separated perfectly. We have then tried to obtain ultrasonic properties of both waves and investigated the reflection and transmission at the interfaces.
A micro-machined microphone based on field-effect-transistor and electrets
Authors: Shin Kumjae , Je Yub , Lee Haksue , West James E. , Moon Wonkyu
Published: April 2012

Micro-machined microphones are attaching attention of industry because of their benefit of size over conventional ones. Since most of micro-machined microphones are capacitive sensors, the sizes of their electrodes determine the low frequency noise level that increases with inverse of frequency (1/f). Therefore, the size of microphone itself becomes larger than the one that can be fabricated. Here we introduce a micro-machined microphone that can overcome the limit of capacitive microphones. The proposed microphone is composed of a field-effect-transistor (FET) and an electret. The difference between the conventional electret capacitive microphones and the proposed microphone may be the transduction mechanism: the change in the position of an electret causes the change in electric field on the gate of FET. Compared with capacitive transduction, the resistive channel of FET can be designed to have low sensor impedance, and subsequntly have low impedance at low frequency. To make experimental specimen, FET onto membrane and electret were fabricated with conventional metal-oxide-semiconductor fabrication process and micromachining process, respectively. The FET membrane chip and the electret chip were assembled. Simple current to voltage converter was applied as a pre-amplifier. Its feasibility to apply low frequency acoustic sensor will be proved by simulation and experimental results.
CAA-based optimisation of a sensor array to characterize aft and forward fan noise in a 3D nacelle
Authors: Mincu D.-C. , Manoha E. , Polacsek C.
Published: April 2012

In the context of the on-going European project JTI-SFWA, the modal acoustic content inside a realistic fan duct, designed by Dassault-Aviation, must be characterized experimentally. The objective is to use Onera's CAA solver sAbrinA-V0 to design a non-intrusive sensor distribution inside the nacelle, upstream/downstream the fan plane, accounting for the heterogeneous mean flow and the complex internal geometry. By computing the propagation of several interacting modes in the duct, a region in which the acoustic pattern is close to the infinite duct analytical solution was characterized. Then several 3D distributions of pressure sensors were tested in this zone. Radial and azimuthal sensor arrays were located at the nacelle wall, whereas a radial sensor array was placed along the bifurcation leading edge, without additional intrusivity. The response of the 3D arrays to a given acoustic field, either analytical or propagated through CAA, was projected on an analytical modal basis. For several array configurations, this projection clearly showed the emergence of the modal injected content. From these simulations, the most efficient sensor distribution will be used to equip an experimental fan noise simulator, and the modal projection process will be applied on measurements to evaluate the actual modal content in the duct.
Strike notes and their pitches of some kinds of bells
Authors: Yoshikawa Shigeru , Cho Wang-Ho , Toi Takeshi
Published: April 2012

The strike notes of western church bells have been studied very long. This paper considers the bells that are different from church bells: (1) simple tubular bells called “wind chime”, (2) a downward-stretching tubular bell with hyperbolic surface, which the authors name “Gaudi bell” because Antoni Gaudi envisaged music of such bells coming from the belfries of the Sagrada Familia Church, and (3) a double Gaudi bell stretching downward and upward from the center with different lengths. Strike notes of these bells are yielded from the axial vibrations. However, their pitches do not necessarily correspond to the strongest spectrum (mode) of the bell vibrations. Aluminum tubular bells of our wind chime gave the “spectral pitch” determined by the spectral frequencies (around 1 kHz) of the fourth mode. On the other hand, our Gaudi bell (brass-made, 1.80 m, 50 kg) yielded the fourth mode at 750 Hz. However, many listeners perceived the pitch at 375 Hz. This is the “virtual pitch” based on the missing fundamental (mode frequencies higher than the 4th were 1082, 1450, 1842, and 2258 Hz). A double Gaudi bell (bronze-made, 0.342 + 0.260 m) gave the “spectral pitch” at 1125 and 2046 Hz.
Gabor domain analysis of mambranophones
Authors: Ferguson Robert
Published: April 2012

Advanced analysis methods of exploration seismology are applied to the study of a class of membranophones that are well modelled as three spring damped oscillators. As a first attempt, damping is ignored in this treatment. Analysis using vibroseis-like source sweeps, cross-correlation, Fourier decomposition, and Gabor domain analysis provide insight into how this class is tuned for use in jazz and popular music. It is found that for a particularly good set of three example membranophones, they are tuned to pitches such that they resonate in combinations that are particularly harmonious. Combinations of octave, perfect fourth, and perfect fifth are found and, in particular, the Gabor domain is most useful for discrimination of resonant tones from the ambient noise of the recording system and surroundings.
Revision of the new orleans noise code in regard to soundscape, enforcement, and cultural impact
Authors: Woolworth David
Published: April 2012

New Orleans is a city with districts of predominately residential historical structures that overlap with entertainment districts that play host to a tourist based economy, in addition to being the home of rich cultural traditions that include live music and Mardi Gras Carnival. As tourist and entertainment venues and their noise levels increase and expand, residents of mixed use areas are becoming less tolerant of the noise and are vacating the French Quarter that depends on their presence for the vitality of these districts. The complex layers and conflicting schedules of neighborhoods, entertainment zones, and frequent music festivals make a difficult case for enforcement. This paper outlines the methods for assessing the existing conditions and making the code revision to begin the process to strike a balance in the French Quarter and keep future development of the rest of the city in check.
Recognition of Mandarin Chinese in noisy, reverberant environments
Authors: Li Liang , Wu Xihong , Schneider Bruce
Published: April 2012

Cochlear-implant users partially recover their speech intelligibility in quiet but not in a noisy, reverberant environment, particularly for those speaking tonal languages, for which semantic information is also expressed by pitch contour. To improve cochlear-implant algorithms for tonal-language users, we have investigated speech recognition in Mandarin-Chinese speaking listeners under adverse listening condition to address four issues related to perceptual fusion and informational masking. First, to what extent do Chinese speech and non-speech sounds differ with respect to the tendency of perceptual fusion (between direct and reflected waves)? Second, why does perceptual separation provide a smaller release from informational masking in Mandarin Chinese than in English? Third, can the use of the recently developed simulated phase-locking stimulation strategy (SPLS, which extracts both phase and amplitude-envelope information) improve speech perception in Mandarin-speaking cochlear-implant patients compared to the continuous interleaved sampling strategy (CIS) currently in use? Fourth, does the prior presentation of a sentence spoken in quiet, by the same person who immediately afterwards produces a masked target sentence, improve identification of the masked target (voice priming) only for tonal-language speaking listeners?
Multiple maskers for speech masking in open-plan offices
Authors: Wang Yue , Drotleff Horst Albert , Li Ping
Published: April 2012

Sound masking is an effective method to reduce speech intelligibility for reaching acceptable speech privacy in open-plan offices. Speech-like masker is considered as a good choice to reduce speech intelligibility. Using one masker in masking system is the common way so far. In this paper, a new method was proposed, using randomly integrated speech frames (SF) of the speaker as masker. Because SF masker was based on speech of the same speaker, it is a good speech-like masker. We further studied the method of using multiple SF maskers. The performance of this new masking method was evaluated by objective measurement (STOI). The speech masked by one SF masker and multiple SF maskers were compared. Results showed that speech with SF masker could reduce speech intelligibility. Speech with multiple SF maskers led to poorer speech intelligibility than speech with only one SF masker. Masking speech by multiple SF maskers is an effective way to reduce speech intelligibility in open-plan offices. (Acknowledgement: This research was supported by the joint training PhD program of Chinese Academy of Sciences-Fraunhofer, and Fraunhofer Institute of Building Physics in Stuttgart, Germany.)
Lake test of 70 kHz correlation velocity log for AUV
Authors: Wang Changhong , Chen Long , Qiu Wei , Wang Yuling
Published: April 2012

A 70 kHz correlation velocity log (CVL) for AUV has recently been developed. The hardware design and signal processing were discussed. Localized least mean squares (LLMS) algorithm was proposed as the criterion of velocity estimation. The CVL underwent lake trials in Qiandao Lake Sea both on a ship and an AUV in Aug 2011. The CVL was calibrated. Trackline test, varying speed cruise test and drifting test were carried out to examine the performance of the CVL. The uncertainty statistics from the lake trial showed that the velocity accuracy of the CVL was about 0.8%V. This work was supported by Knowledge Innovation Project of Chinese Academy of Sciences.
Gliders, floats, and robot sailboats: autonomous platforms for marine mammal research
Authors: Mellinger David K. , Klinck Holger , Bogue Neil M. , Luby Jim , Matsumoto Haru , Stelzer Roland
Published: April 2012

Passive acoustic monitoring (PAM), now widely used for marine mammal research, is typically conducted using hydrophone arrays towed behind ships, providing real-time data from large areas over short time spans (days to weeks), or using fixed autonomous hydrophones, providing non-real-time data from small areas over long time spans (months to years). In contrast, mobile platforms can supply near-real-time data over spatiotemporal scales large in both space and time. These systems are deployed from a vessel, communicate via satellite with shore stations for navigation and control updates, and report in near-real time upon detecting marine mammal or other sounds of interest. Acoustically-equipped gliders are buoyancy-driven devices that are capable of traversing long distances (hundreds to thousands of kilometers) over weeks to months of autonomous operation. Autonomous floats such as QUEphones drift with currents or park on the seafloor, rising to the surface upon detecting sounds of interest. Robot sailboats such as the Roboat use wind to propel themselves quickly over long distances. All platforms can store large datasets and carry additional sensors (e.g., temperature, salinity, chlorophyll, pH, O2), and are therefore well-suited for investigating oceanographic and ecological questions. Advantages and disadvantages of these platforms for various applications will be discussed.
Acoustic design criteria in green building rating systems
Authors: Kwok May Han Grace
Published: April 2012

Acoustic design aspect has been considered in various green building rating systems as part of the sustainable building design approach in an attempt to ensure a desirable acoustic environment for the future occupants. Primarily, the focus is on speech privacy, background noise control and noise isolation in a general building setting. In this paper, the acoustic design criteria adopted by different green building rating systems, including LEED in the United States, China Green Building Label in China, BREEAM in Britain, Green Star in Australia, CASBEE in Japan, BEAM Plus in Hong Kong, are evaluated in a comparative study with pros and cons highlighted. Selected criteria are investigated against respective regulatory requirements and common acoustic design standards and practices. The potential implications on building design and construction as well as the associated benefits to building users are also discussed. Possible conflicts and synergy with other sustainable design aspects in the green building rating systems are addressed. Lastly, acoustic design strategies and post-occupancy acoustic surveys for green buildings are recommended.
Diffuse ultrasonic backscatter in two-phase media
Authors: Liu Dalie , Turner Joseph
Published: April 2012

The microstructure of sintered metals and ceramics may be modeled as two phases consisting of the particles and a surrounding matrix during certain processing stages. Diffuse ultrasonic backscatter has been widely used to extract the microstructural parameters and also to detect flaws in such materials. In this research, a singly-scattered response model is used to predict the grain noise for the two-phase model. The expression of backscatter coefficient is derived and found to be dependent on the spatial correlations of the material properties. The geometric two-point correlation function plays an important role in this model and can be determined from numerical correlation statistics. Good agreement is found between the results determined from the model and the experimental results.
Acoustic-gravity waves in ocean and atmosphere generated by an underwater source
Authors: Fuks Iosif , Godin Oleg A.
Published: April 2012

Air-water interface becomes anomalously transparent, and the power flux in the wave transmitted into the air increases dramatically, when a compact sound source in water approaches the interface within a fraction of wavelength [O.A. Godin, Phys. Rev. Lett. 97, 164301 (2006)]. The anomalous transparency of the ocean-atmosphere interface has important implications for detection of underwater explosions and monitoring of compliance with the Comprehensive Nuclear Test Ban Treaty. At wave frequencies below 0.1 Hz, it becomes necessary to take gravity into account. Then fluid buoyancy and compressibility simultaneously serve as restoring forces, and mechanical perturbations in the water and in the air propagate as acoustic-gravity waves (AGW). It was previously shown [I. Fuks and O.A. Godin, Proc. OCEANS'11, MTS/IEEE, Kona, HI, Sept. 2011] that, in the case of a shallow source in an ocean of an infinite depth, a sharp peak in the power flux into air appears at frequencies close to a cutoff frequency of about 4mHz of a surface acoustic-gravity wave. In this paper, we extend these results to the ocean of a finite depth where the AGWs interact with an elastic bottom.
Acoustical emission of jet-edge systems using a vibrating element in water
Authors: Li C , Deng Jingjun , Bai Lixin
Published: April 2012

The jet-edge system using a vibrating element (liquid whistle) was investigated experimental using high-speed camera. The vibrating element vibrated periodically with a few millimeters displacement and cavitaion bubbles were observed near the tip of the vibrating element. The acoustic emission of the system was measured with hydrophones in some place. The low frequency and shock signals were observed in the pressure signal, and whistle can be heard at the same time. In frequency field, the line and broadband spectrum exist. The foundation frequency f0 of the vibrating element and harmonics compose the line spectrum. The former 10 order harmonics can be seen obviously. As the flow velocity increasing, the frequency f0 and the harmonic do not change, but the intensity of the high order harmonics and broadband spectrum become strong. Base the experimental result, we consider that the f0 is the foundation frequency of the vibrating element, and the harmonics and the continuous spectrum is the bubble cavitation emission. Acknowledgement: This work was supported by the National Natural Sciences Foundation of China (10804118)and he National Science and Technology Major Project of China (No. 2011ZX05032-003)
Attentional modulation of EEG signals
Authors: Choi Inyong , Bharadwaj Hari , Shinn-Cunningham Barbara
Published: April 2012

Physiological measures revealing effects of selective attention are needed to develop insights into how auditory attention is controlled. Here, we used electroencephalography (EEG) to measure neural activity when listeners attended one of two competing auditory streams. Listeners identified whether a target three-tone melody had a rising, falling, or non-monotonic pitch contour while ignoring a competing, simultaneous melody. To enhance stream segregation, the streams differed in timbres (oboe and cello) and perceived lateral position (to the left, to the right). We “tagged” each of the streams by adding amplitude modulation (AM) at different gamma-band frequencies. We found that the evoked gamma activity at the AM frequencies was statistically above the noise floor, and depended on the spatial configuration and the modulation frequency, as might be expected. Importantly, for identical acoustic inputs, the relative strength of the AM frequencies depended on which stream a listener attended. Moreover, the pattern of responses depended on what cue directed the listener to attend to a particular target. Results suggest that the control of attention engages different neural networks, depending on the feature directing attention. These results will be discussed in light of efforts to develop brain-machine interfaces that monitor auditory attention.
The effect of spectral asynchrony on speech recognition in demanding listening conditions
Authors: Wojtczak Magdalena , Rai Sachin , Beim Jordan A. , Oxenham Andrew J.
Published: April 2012

Speech recognition is remarkably robust to overall spectral asynchronies as large as 160-180 ms when performance is measured in quiet. One reason for such robustness may be substantial redundancy in the speech stimulus. This study investigated the effect of spectral asynchrony on speech recognition in listening conditions yielding 80% or less correct recognition score for synchronized speech (baseline condition). IEEE sentences mixed with a speech-shaped noise or two-talker babble were divided into 1/3-octave bands. Successive bands were progressively delayed from low to high, or from high to low, center frequency. The overall delay between the lowest and highest-frequency channels was varied between 0 and 160 ms. The difficulty of the task in the synchronous condition was determined by different signal-to-noise ratios and by presenting either the full stimulus or a lowpass-filtered version. The results show that performance is less robust to spectral asynchrony when speech is presented with an interfering background, although it remains relatively unchanged for overall delays up to 40-ms, independent of the direction of the delay as a function of frequency. The results were analyzed using the speech transmission index. [Supported by NIH grant R01DC010374].
Auditory and cognitive factors in speech and environmental sound perception of cochlear implant listeners
Authors: Shafiro Valeriy , Sheft Stanley , Kuvadia Sejal , Gygi Brain , Ho Kim
Published: April 2012

This study examined the role of acoustic pattern discrimination abilities and higher-order cognitive factors on the perception of spectrally degraded speech and environmental sounds. Over the course of four testing sessions and a week of environmental sound training, cochlear implant and normal-hearing listeners (tested with a 4-channel implant vocoder simulation), received a 160-item environmental sound test, and isolated word and sentence tests. Listeners were also tested with a battery of cognitive tests which included measures of inhibition, closure, working memory and executive function, and a battery of psychoacoustic tests of spectral and temporal pattern processing. A great deal of overlap in the processing abilities for speech and environmental sounds was found in both groups of listeners. Centrally, speech and environmental sounds were associated with working memory and executive function measures (i.e., digit-span-backward, letter-number sequence). Psychoacoustically, the two sound classes were associated with measures of spectral resolution and temporal fine-structure processing. These findings indicate that successful perception of acoustically complex meaningful patterns under conditions of spectral degradation involves joint contributions from specific peripheral factors and central processes, and suggest directions for improving listener performance through training [Support provided by NIH/NIDCD].
Word retrieval process uses phonemic cues in memory-impaired epilepsy analyzed by Rey's auditory verbal learning test
Authors: Asano Keiko , Okura Hidehiro , Sugano Hidenori , Nakano Mitsuko , Fusegi Keiko , Arai Hajime
Published: April 2012

This study investigated what kinds of phonemic strategies memory-impaired patients with diagnoses such as frontal lobe epilepsy compared to the strategies healthy people use in order to memorize and retrieve words in the aspects of Rey's Auditory Verbal Learning Test (AVLT). This Auditory Verbal Learning Test is widely used in the field of clinical and neuropsychological assessments to examine word learning and memory. This test has two stages: A list of 16 unrelated, concrete nouns is presented over five learning trials with immediate recall tested following each presentation. After a delay interval of 30 minutes with no further presentations of the list, delayed recall is assessed. The number of words correctly recalled is commonly adopted as quantitative information in clinical assessment. After the tests, participants are asked what kinds of strategies they used to memorize the words in terms of examining the process of decoding, recall and retrieval. Spontaneous memorization strategies used by memory-impaired patients are visual-oriented and episode-making, whereas the most healthy people use the method of grouping a few words as one chunk. Contrary to self-monitoring strategies, especially among the epilepsy patients, phonemic cues are unconsciously used to retrieve the words. The implication on the function of different brain areas activated between patients and healthy people will also be discussed.
Boundary tones in production and comprehension of in pro-drop language: the case of Korean
Authors: Ahn Hyunah
Published: April 2012

This paper investigates if boundary tones have either a gradient or a categorical indication of structural phrasing. The role of prosody in syntactic disambiguation has been well documented and a recent study showed Korean speakers use the presence and absence of boundary tones to disambiguate a null-argument sentence borne out of double nominative construction in Korean (Ahn, 2011). Two experiments show that boundary tones play an important role both in comprehension and in production in spoken Korean. In Experiment 1, speakers read a paragraph including contexts and the critical sentence given in a latin-square design. The critical sentences in this production experiment include both null-argument and non-null-argument sentences to see if the use of boundary tones is for addressees or for the speaker himself. In Experiment 2, participants judge the naturalness of null-argument sentences given in contexts and answer comprehension questions probing if they got the correct reading of the two ambiguous interpretations. The results show a clear interaction effect of prosody and structure on the accuracy to the comprehension questions. A gradient-categorical dichotomy of prosody in sentence processing will be discussed and suggestions for a further study will be made to investigate the relationship of boundary tones and comprehension.
Envelope pitch at different stimulation sites of cochlear implant
Authors: Meng Qinglin , Yuan Meng , Mou Hongyu , Feng Haihong
Published: April 2012

Pitch perception researches showed that temporal modulation plays an important role in pitch perception from unresolved harmonics. Fundamental frequency (F0) enhancement through temporal modulation of envelope was utilized in some cochlear implant (CI) signal processing strategies [e.g., Laneau, et.al., 2006] to improve the pitch perception of CI. In this study, Temporal Modulation Transfer Function (TMTF) and the relationship between Amplitude Modulation Rate (AMR) and pitch perception at different stimulation sites (apical, middle, and basal) were investigated. The stimuli are sinusoidal-amplitude–modulation pulse trains. Two psychophysical experiments were carried out: Two-Alternative-Forced Choice on modulated/un-modulated stimuli and AMR-Pitch Ranking. Experimental results showed that some of the CI subjects exhibited distinct performance at different stimulation sites, which implies that issues of stimulation sites and the subject's individual performance should be considered for F0 enhancement strategies on CI. More experiments are in progress and whole results will be shown on the conference.# This work is supported by National Natural Science Foundation of China (11104316), and Shanghai Natural Science Foundation (11ZR1446000).
Loudness of sounds with a subcritical bandwidth
Authors: Hots Jan , Rennies Jan , Verhey Jesko Lars
Published: April 2012

The predicted loudness for narrowband signals with bandwidths smaller than the bandwidth of the auditory filter, i.e., with a subcritical bandwidth, depends on the type of loudness model. While models analyzing the long-term spectrum (stationary loudness models) predict loudnesses for these subcritical signals which are independent of the bandwidth of the sound, models sensitive to the temporal structure of the signal (dynamic loudness models) predict higher loudnesses for narrowband noise signals than for tones due to the inherent level fluctuations of the noise. The present study measures the loudness of subcritical sounds for center frequencies of 750, 1500, and 3000 Hz. For all three center frequencies, the level of the narrowband noise had to be up to 5 dB higher than the level of the equally-loud tone at the center frequency. This experimental finding is at odds with both predictions, i.e., the loudness is neither the same for all signals nor is the level of the narrowband noise smaller than that of the equally-loud tone. The data indicate a special character of sounds with a distinct tonal character which is not accounted for in current loudness models.
Comparison of pure tone thresholds obtained via automated audiometry and standard pure tone audiometry
Authors: Eddins David A. , Walton Joseph P. , Dziorny Adam E. , Frisina Robert D.
Published: April 2012

It is likely that the role of automated audiometry will expand in both clinical and research settings in the next few years. A novel method for measuring pure tone thresholds using an automated threshold measurement method is reported here. The Automated Audiometry for the NIH Toolbox (AANT) test was developed for use in the NIH Toolbox multi-disciplinary evaluation battery which contains over 20 tests of sensory function and cognition. Development goals included low system cost, high accuracy, test administration time under 10 minutes, and automated calibration and measurement procedures suitable for use by evaluators without specialized training. Here we report the results of a validation study in which pure tone thresholds obtained using the AANT algorithm and hardware are compared to pure tone thresholds measured using the gold standard clinical method, standard audiometric hardware, and experienced examiners. Air-conduction thresholds will be reported for test frequencies of 500, 1000, 2000, 4000, 6000, and 8000 Hz using both methods. Additional measures for each subject include otoscopy, screening tympanometry, and the Hearing Handicap Inventory for Adults or Elderly. Data will be reported for 100 subjects between the ages of 4 and 85 years in age ranges.
Sound source localization in the horizontal plane through the bilaterally applied bone-conducted ultrasonic hearing aids
Authors: Hotehama Takuya , Nakagawa Seiji
Published: April 2012

Bone-conducted ultrasound (BCU) can be perceived not only by normal hearing but also by the profoundly hearing impaired who cannot make use of a conventional hearing aid. BCU hearing aid (BCUHA), in which an ultrasonic carrier is amplitude-modulated (AM) by collected external sound and presented through a bone-conduction vibrator onto the mastoid portion, has been developed for the profoundly hearing impaired. To obtain useful information in order to realize accurate sound source localization through the BCUHAs. In this study, localization performance in the horizontal plane through bilaterally applied BCUHAs was investigated by psychological experiments. Results show that subjects hardly lateralized when the BCUHAs were simply applied bilaterally with the double-sideband modulation method. On the other hand, the localization performances were improved when the inter-lateral intensity and time differences of presenting signals of BCUHAs were enhanced on the basis of those of the collected external sounds and when the “transposed modulation” was employed as the modulation method. Our results suggest the necessity of the inter-lateral cooperative system to modify the spatial parameters of the output signal for accurate sound localization through the BCUHAs.
Effects of interaural level differences on the externalization of sound
Authors: Catic Jasmina , Santurette Sebastien , Dau Torsten , Buchholz Jörg
Published: April 2012

Distant sound sources in our environment are perceived as externalized and are thus properly localized in both direction and distance. This is due to the acoustic filtering by the head, torso, and external ears, which provides frequency-dependent shaping of binaural cues such as interaural level differences (ILDs) and interaural time differences (ITDs). In rooms, the sound reaching the two ears is further modified by reverberant energy, which leads to increased fluctuations in short-term ILDs and ITDs. In the present study, the effect of ILD fluctuations on the externalization of sound was investigated. A psychoacoustic experiment was performed in a standard IEC 268-13 listening room by normal-hearing listeners. Individual binaural room impulse responses were used to simulate a distant speech source delivered via headphones. The speech signal was then processed such that the naturally occurring fluctuations in the ILDs were compressed, while the ITDs were preserved. This manipulation reduced the perceived degree of externalization mainly for broadband and highpass filtered speech. In the case of lowpass filtered speech, the compression of ILD fluctuations did not affect externalization. Overall, for sounds that contain frequencies above about 1 kHz the ILD fluctuations were found to be an essential cue for externalization.
New generation pinger using pseudo noise sequence signal
Authors: Sasakura Toyoki
Published: April 2012

Ultrasonic biotelemetry system is one of the useful methods to observe fish migration and behavior. New generation pinger, which has small size, long life, long distance and high recognition ability was developed using pseudo noise sequence signals.. Size, lifetime, distance and collision avoidance are tradeoff relation each other. To solve this, the advanced technology using CDMA mobile phone communication was adopted. Pseudo noise sequence signal was applied for transmitting signal and correlation processing was used for receiving signals. The transmitting signal consisted of 31 bits pseudo noise sequence signal and the correlator of receiving signal was 992 steps using FPGA(Field Programmable Gate Array). As a result, the new pinger has the size of φ10×35mm long including depth sensor, sound transmission lasts 240 days when 30 seconds repetition using the small battery SR626SW 32mAh. The signal could be achieved over 1,000 meters distance in a field validation. A unique set of 32 ID codes of the pseudo noise sequences were found to minimize collision of identification. In addition, depth and temperature information could be transmitted. The new generation pinger contributes not only to the research work of biotelemetry but also to fisheries and aquaculture purposes in the world.
Sperm whale coda communication studied with multiple acoustic tags
Authors: Madsen Peter Teglberg
Published: April 2012

Female sperm whales spend their entire lives in matrilineal groups with long term social bonds. However, contrary to other toothed whale species with a complex, long term social structure, sperm whales seemingly only use stereotyped patterns of clicks, named coda, to radiate acoustic clan identity with little or no signature encoding. Due to their deep diving behavior in offshore water, it is difficult to study the acoustic behavior and source properties of sperm whale communication signals. To alleviate that, multiple acoustic Dtags was deployed on sperm whales to study the behavioral context and source parameters of coda production. It is shown that more than 50% of all codas are produced during deep dives where the active space can cover the entire foot print of the social group despite low apparent source levels of around 180 dB re 1uPa. Intra click information in the form of spectral and IPI information is heavily distorted as a function of aspect with little room for individual encoding. The unequivocal assignment of codas to tagged individuals have demonstrated a large potential for information transfer in the inter click intervals of codas suggesting a much more complex acoustic communication in sperm whales than previously proposed.
Two-dimensional multi-layer of arterial elasticity measurement considering geometric transformations
Authors: Niu Lili , Qian Ming , Song Ruibo , Meng Long , Qi Guan , Liu Xin , Zheng Hairong
Published: April 2012

Knowledge of the arterial elasticity can provide an important reference for understanding arterial wall changes that may occur before and during the early stages of atherosclerosis. In practice, the movements of arterial wall during the cardiac cycle are complex, which undergo not only translation but also rotation and deformation subjected to pulse pressure, transmural pressure and shear force. Conventional correlation based methods for arterial wall movement evaluation consider only the translational component and limit their accuracy. This study proposes a texture matching method based on ultrasonic B-mode image for accurately measurement the movement of the arterial wall with geometric transformations, improving the accuracy of elasticity measurement. Feasibility of the method was studied in an in vitro silicone tube phantom and in vivo carotid arteries of mice. The calculated elastic modulus for the in vitro silicone tube agrees well with the results obtained from mechanical testing, deviating only 6.2%. The mean elastic modulus of the carotid arteries of mice is 122.4±29.2kPa. The results demonstrate that the texture matching method can measure elastic modulus of the arterial wall with geometric transformations accurately. It may be clinically useful for aiding early detection of atherosclerosis.
Synchronization intercomparsion method and sea trials of acoustic doppler current profiler (ADCP)
Authors: Wu Jianbo , Deng Kai , Gao Chao , Li Jun , Wang Changhong
Published: April 2012

The advantage and disadvantage of intercomparsion methods adopted routinely for performance comparison of Acoustic Doppler Current Profiler (ADCP) were analyzed. A new ADCP intercomparsion method was introduced, by which ADCPs were synchronized to work alternately ping by ping in the same steady platform, and the requirements for achieving creditable comparing measurements were also discussed. Several intercomparsion tests of two ADCPs at mooring shelves and subsurface buoy were conducted in northern South China Sea. One ADCP is 150 kHz self-contained ADCP made by Institute of Acoustics, the other is RDI 150 kHz Quartermaster ADCP. A statistical method was used to process the measurement data obtained through the new intercomparsion method, and criterions were adopted to evaluate the performance of ADCPs. Comparing with other methods, the synchronization intercomparsion method is more objective and credible.
Humidity measurement using a ultrasonic probe based on sound attenuation
Authors: Motegi Takahiro , Mizutani Koichi , Wakatsuki Naoto
Published: April 2012

Measurement of spatial average humidity has been required for air conditioning management in facilities, to obtain a change tendency of environment. For example, spatial humidity management is important to prevent the damage of cultural assets. However, conventional sensors such as wet-dry hygrometers measure the local humidity at a measurement point and do not reflect the spatial humidity. In this paper, humidity measurement using a ultrasonic probe is proposed. A ultrasonic probe, which measures the sound attenuation coefficient in acoustical path, reflects the averaged humidity among the path and achieves non-contact measurement of the spatial average humidity between ultrasonic transducers. The performance of the proposed technique is evaluated in experiment, and it is found that if the probe knows the information of temperature, humidity can be successfully measured from sound attenuation coefficient.