bluuebunny/crossref_metadata_2025 huggingface dataset:
Impact noise insulation performance of commonly used materials when excited by different impact noise sources
Authors: Panosso Andriele d. , Paul Stephan
Published: November 2016

This study aimed to verify the performance of different materials used as impact noise insulation when excited by different impact sources. The method applied consisted of several acoustic measurements, following the standards' instructions and using different impact sources, such as the tapping machine and an impact tire. When using the tapping machine results indicate rather big differences in noise insulation performance for the different materials, showing a range from 50 to 76 dB for the Weighted Standardized Impact Sound Pressure Level while measurements with the tire showed a range of 72 to 82 dB for the Average Maximum Impact Pressure Level, meaning very similar noise insulation for all materials.
Information-seeking in an echolocating dolphin
Authors: Harley Heidi E. , Fellner Wendi , Frances Candice , Thomas Amber , Losch Barbara , Feuerbach David
Published: November 2016

Dolphins gain information through echolocation, a publicly accessible sensory system in which dolphins produce clicks to investigate objects. We measured information-seeking behavior by counting clicks that a blindfolded dolphin directed toward the sample object in a three-alternative matching task with object sets that varied in discriminability: Indiscriminable (performance accuracy M = 33%) vs. Easy (performance accuracy M>90%). The dolphin produced a similar number of clicks when first investigating each set type. Across multiple sessions, however, the dolphin emitted fewer clicks only when investigating indiscriminable (vs. easy) sets. Reduced echoic investigation with indiscriminable, but not easy, object sets was not due to overall motivation: the differential relationship between click number and object set discriminability was maintained when difficult and easy trials were interleaved and when objects from originally difficult sets were grouped with more discriminable objects. Further analyses of the dolphin’s click production towards the choice alternatives also revealed that the dolphin produced more clicks towards the chosen (vs. unchosen) alternatives when solving the task. Overall, these data suggest that dolphins calibrate the effort they invest in information seeking in accordance with the information content available in their immediate environment.
Comparison of quantitative ultrasound parameters from two approaches on in vivo human fatty liver
Authors: Muleki-Seya Pauline , Han Aiguo , Andre Michael P. , Loomba Rohit , Sirlin Claude B. , Erdman John W. , O'Brien William D.
Published: November 2016

Two different quantitative ultrasound (QUS) processing strategies are evaluated and compared. The first method estimates the Lizzi-Feleppa (LF) parameters from the linear fit of the normalized power spectrum, and yields the slope, the intercept, and the midband. The QUS approach relies on the attenuation and BSC versus frequency, and yields the mean attenuation and BSC. By using the spherical Gaussian model, the effective scatterer diameter (ESD) and acoustic concentration (EAC) are estimated from the BSC. The goal of this study is to compare the LF and QUS parameters to determine how they are correlated and to verify their correlation with ESD and EAC. To do this, RF data were acquired using a Siemens S3000 from 20 patient livers (suspected of Non-Alcoholic Fatty Liver Diseases (NAFLD)) and from these spectra, the LF and QUS parameters were estimated. The liver fat fraction for each patient was estimated using MRI, and ranged from 0.03 to 0.3. The results show that LF slope is correlated to ESD (R2 = 0.75), LF midband to EAC (R2 = 0.70), and LF intercept to ESD and EAC. A very high correlation between LF midband and the mean BSC is observed (R2 = 1.00), along with the fat fraction (R2 = 0.63). [Support: NIH R01DK106419.]
A quantitative imaging biomarker alliance
Authors: Hall Timothy J. , Garra Brian S. , Carson Paul L. , Milkowski Andy , Fowlkes J B. , Kripfgans Oliver , Barr Richard G. , Averkiou Mike
Published: November 2016

The Radiological Society of North America (RSNA) created the Quantitative Imaging Biomarker Alliance (QIBA) to convert “imaging systems” with subjective image interpretation to “measurement systems” with objective measurands having actionable numerical values. The goal is to create QIBA protocols and profiles that specify methods for data acquisition, analysis, and interpretation. QIBA profiles also provide specific claims of what can be accomplished by following the QIBA protocol. The intent is to validate the profile across imaging systems in a collaboration between industry, government (NIH, FDA, NIST), Pharma, clinicians, and academics. The RSNA/QIBA effort includes over 850 volunteers worldwide with Biomarker Committees for all major imaging modalities. The effort is expanding with collaborations in Japan (the Japan Radiological Society’s QIBA-Japan) and in Europe (European Institute for Biomedical Imaging Research and the European Imaging Biomarker Alliance; EIBIR—EIBALL). The QIBA ultrasound group began with a committee to investigate and minimize sources of bias and variance in shear wave speed estimates for liver fibrosis assessment. The group has grown to about 200 members and includes committees to advance biomarkers based on measurement of volume blood flow and parameters derived from contrast-enhanced ultrasound. The status and implications of these efforts will be presented.
Comparison of zooplankton density estimated by acoustic inversion method and net sampling
Authors: Sawada Kouichi , Mukai Tohru , Fukuda Yoshiaki , Matsuura Tomohiko
Published: November 2016

A multi-frequency acoustic zooplankton fish profiler (AZFP, ASL Environmental Sciences) with temperature-salinity and depth sensor was moored at 10 m from the bottom (ca. 30 m) at the mouth of Yamada Bay in Iwate Prefecture, Japan, from 14 January to 16 June 2015 in order to measure volume backscattering strength profiles from the transducer surface to the water surface at four frequencies (125, 200, 455, and 769 kHz). Zooplankton density by size was estimated from the measured volume backscattering strength at four frequencies by the inversion method. Monitoring period was selected to cover the period when juvenile salmon stay in the bay before leaving for oceans. Zooplankton sampling was conducted periodically (once a week or two weeks, day and night) using a Kitahara Net (30 cm dia., 335 µm mesh) and a Norpac Net (45 cm dia., 335 µm mesh) at near the moored position. These observations revealed that large zooplankton, which juvenile salmon prefers, arrived with the Oyashio Current, and the zooplankton density increased from late April to the middle of May. Acoustically estimated variation pattern in zooplankton density over time was similar to that obtained by net sampling. [This work was supported by AFFRC, Japan.]
Noise suppression based on loudness management for hearing aid
Authors: Hiramoto Takeru , Hiruma Nobuhiko , Nakashima Hidetoshi , Fujisaka Yoh-ichi.
Published: November 2016

It is well known that speech intelligibility does not improve even if SNR is improved and noise annoyance decreases by noise suppression for hearing aids, since the noise suppression decreases the level of the desired signal as well as the one of the noise. One solution for the problem is to minimize the speech distortion as much as possible even if a large quantity of residual noise exists. In this study, we propose a noise suppression algorithm based on loudness management to improve speech intelligibility for hearing aid wearer. Our algorithm not only minimizes the speech distortion but also maintains the speech loudness. In the algorithm, the speech spectrum is estimated from the observed signal first, and then the loudness of the estimated speech spectrum is calculated. Simultaneously, the loudness of the observed signal is also calculated and the gains in each frequency band are controlled in order to correspond between these two loudness. In our loudness management, even if the bands are almost filled by noise component, it is not suppressed as much as possible not to reduce barely audible speech component. As results, the noise suppressed signal with low speech distortion is obtained and speech intelligibility is improved comparing with commonly used method.
Low latency dereverberation with considering speech naturalness for hearing aids
Authors: Nozaki Kotoyo , Ikeda Yusuke , Oikawa Yasuhiro , Fujisaka Yoh-ichi , Sunohara Masahiro
Published: November 2016

It is well known that long reverberation makes speech unclear especially for hearing impaired. For a long time, a lot of researches on dereverberation have been studied. However, the computational cost of most of those methods are too expensive for hearing aids. Therefore, we have proposed the simplified dereverberation method, which can estimate reverberation energy from observed signal. In addition, it is also necessary implementing the processing with low latency to avoid an annoyance for hearing aid wearer. Processed signal have to be natural as much as possible to reduce listening effort, although there is performance limit because of simplicity. In this study, we make two proposals in our previous method. First, we apply Frequency-Warped Filterbank (FWF) in analysis and synthesis systems in order to make frequency bands as Bark scaled alignment, and to take the tolerable latency all over frequency for hearing. Second, we introduce the gain control in each frequency to maintain naturalness of processed speech, because reverberation energy varies depending on frequency bands in actual reverberant environments. From subjective experiments, there was a tendency that they prefer this proposal to the previous method.
INCE/J Vibration Measurement Manual for Buildings—Part 4: Measurement of ground propagation characteristic and long-term measurement in building for road traffic vibration
Authors: Kazama Ryosuke , Yamashita Kodai , Umayahara Hiromitsu , Hasumi Toshiyuki
Published: November 2016

Vibration Measurement Manual for Buildings, issued by Technical Subcommittees on Environmental Vibration Evaluation of The Institute of Noise Control Engineering of Japan, describes how to measure and evaluate vibration. According to the manual, vibration level and 1/3 octave band vibration acceleration levels, which are calculated from tri-axial acceleration waveforms, are used as measurement values. For the values of each axis, we extracted the 10 maximum values of each band level around the time when vibration levels reached maximum by vibration occurrences. The final measurement result is arithmetic average of the maximum 10 data. Some measuring instruments including vibration level meters, data recorders and waveform analysis software are necessary to obtain the result. To show how to measure vibration and how to operate measuring instruments based on the manual, we report two measurement examples about road traffic vibration which is easily perceptible. First, we measured a ground propagation characteristic at multi points along straight line from vibration source. Second, we conducted a long-term vibration measurement in a building, assuming low occurrence of vibration which caused complaints. As a result, we found that the level of certain frequency bands in vertical direction reached the vibration perception threshold range.
Spectral analysis of absorption characteristics of particulate dampers to mitigate building vibration
Authors: Tavossi Hasson M.
Published: November 2016

Particulate medium can act as efficient damper for building internal and external vibrations. Mechanical properties of the particulate material, their shape and size distributions determine the vibration absorption characteristics of these dampers. It has been shown that an unconsolidated particulate damper act as a bandpass filter for vibration frequencies of mechanical vibrations transmitted through them. The particulate dampers can also have frequency bandgap structure, where transmitted mechanical vibration of a particular frequency is strongly attenuated by absorption and scattering. The samples of non-consolidated uniform fused-silica spherical particulates are subjected to mechanical vibrations of different frequencies and intensities to determine their absorption characteristics as a function of frequency, intensity, and direction of propagation. The effects of a particulate diameter and layer thickness on absorption characteristics are determined experimentally, at low and at high frequency ranges encountered in building vibration. The goal of this investigation is to find the required absorption characteristics for particulate damper for applications to mitigate building vibration.
Flanking sound transmission in connected panels of cross-laminated-timber at low frequencies
Authors: Buchegger Blasius , Ferk Heinz , Schanz Martin
Published: November 2016

The sound transmission between adjacent rooms can be dominated by the structure-borne sound transmission in the flanking walls. A wall can be defined as a subsystem of the overall system based on two coupled rooms. These subsystems show local modes, if they are not connected to each other. In contrast, connected subsystems result in global modes showing a high response of both subsystems, if the comparable local modes have similar eigenfrequencies. The flanking sound transmission especially at low frequencies is reduced, if a generation of such global modes can be suppressed. As a consequence, the flanking sound transmission in buildings can be mitigated significantly using a proper design of the walls (geometry, material, etc.). The principles and the impact of this effect are studied in this paper using numerical models based on the finite element method. Selected constructions are implemented in real size 2D- and 3D-models of two adjacent rooms. Panels of cross-laminated-timber are used because the variable composition of the single layers of a panel allows an extensive variation of the vibration response of the single walls. The results confirm the applicability of the described effect for common practical situations.
Interactions between perception and production during speech sound learning
Authors: Baese-Berk Melissa M.
Published: November 2016

It is frequently assumed that perception and production develop in tandem during non-native speech sound acquisition. However, several previous studies have suggested that simply producing tokens during training can disrupt perceptual learning (e.g., Leach & Samuel, 2009). Here, I present several experiments examining some sources of such a disruption. Further, I ask how learning in production progresses when listeners fail to learn in perception. In the first set of experiments, I examine performance on a discrimination task after training in perception alone, or training perception + production, in which listeners repeat tokens on every trial. In follow up experiments, rather than repeating the training tokens, listeners read an unrelated letter aloud between each perceptual training trial or respond to the unrelated letter with a button press, rather than reading the letter aloud. In a second set of experiments I examine how production learning progresses when learners produce tokens during training. The critical factor examined is whether listeners are able to differentiate between tokens in perception and whether this ability correlates with learning in production. Taken together, the results of these studies suggest that the relationship between perception and production is complex, especially during learning.
Neurobiological constraints on speech learning: Individual differences and plasticity
Authors: Chandrasekaran Bharath
Published: November 2016

A primary goal of auditory neuroscience is to understand how conspecific sounds are represented, learned, and mapped to constructs. Speech signals, conspecific to humans, are multidimensional, acoustically variable, and temporally ephemeral. A significant computational challenge in speech perception (and more broadly, audition) is categorization, that is, mapping continuous, multidimensional, and variable acoustic signals into discrete, behavioral equivalence classes. Despite the enormity of this computational challenge, native speech perception is rapid and automatic. In contrast, learning novel speech categories is effortful, and considered one of the most challenging categorization tasks for the mature brain. I will discuss three lines of ongoing research using multimodal neuroimaging, computational modeling, and behavioral training approaches: a) examine the multiple neural systems underlying successful L2 speech category learning in adulthood, b) assess sources of individual differences in L2 speech category learning, and c) design optimal, neurobiologically constrained training paradigms that reduce inter-individual differences in L2 speech category learning. These studies will provide insights into these fundamental questions: consistent with prior work on visual category learning, are multiple neural systems involved in speech categorization? What is the role of emerging expertise and individual differences in mediating neural and computational processes involved in speech category learning?
Doppler spectral moments of multibeam echosounder data to infer the ascent velocity of methane bubbles emanating from natural seafloor seeps
Authors: de Moustier Christian
Published: November 2016

A multibeam echosounder operating at 500 kHz was deployed on a remotely operated vehicle to detect methane bubble streams emanating from natural seafloor seeps in 1400-m water depths. The sonar transmitted 10-ms tone bursts every 100 ms over a 7°×120° beam, and formed 128 receive beams regularly spaced 0.94° apart over the 120° sector. The sonar head faced upward and signals backscattered from ascending bubbles were sampled at about 6 kHz between 10 m and 50 m from the head. Doppler spectral moments were computed for each ping with the conventional data autocovariance method. For unimodal and symmetric Doppler spectra, the mean power is related to the backscattering strength of the sampled volume, the mean Doppler frequency yields the mean radial velocity of the bubbles, and the spectral width measures the mean velocity uncertainty with some indication of bubble oscillation. Mean ascent velocities of 0.2 m/s matched those obtained from concurrent optical measurements. However, beams free of bubbles showed mean descent velocities of about 1.5 cm/s, most likely due to marine snow, which could bias mean ascent velocity estimates for bubbles at greater distance from the sonar because the corresponding Doppler spectra might no longer be unimodal.
Some effects of ocean surface roughness on high and low duty cycle, broadband waveforms
Authors: Hines Paul C. , Murphy Stefan M. , Abraham Douglas A. , Deane Grant B.
Published: November 2016

In this paper, data from TREX13 are used to compare the impact of the environment on High Duty Cycle (HDC) sonar and Pulsed Active Sonar (PAS). This paper presents the results of an examination of short-range single surface-reflection echoes, and longer-range target echoes from an air hose. Measurements showed that for an 18 s HDC pulse, the mean (coherent) component of the specular arrival decreased with increasing rms roughness whereas 0.5 s PAS pulse echoes showed no correlation with roughness. The standard deviations of the mean echo levels are used to examine the incoherent (scattered) component of the specular arrivals. The incoherent component of the specular arrival increased with the product of the surface correlation length and the square of the rms roughness, for both HDC and PAS, with the PAS data having a 1 dB higher standard deviation. A normal mode propagation model and a rough surface scattering model used in conjunction with a simple model that accounts for motion-induced coherence loss from the matched filter, are used to interpret the results. [Work sponsored by ONR Code 32.]
3D modeling of low-to-mid-frequency acoustic propagation through an estuarine salt wedge
Authors: Reeder D. Benjamin , Lin Ying-Tsong
Published: November 2016

An estuary is an example of a constrained environment which often hosts a salt wedge, the stratification of which is a function of the tide's range and speed of advance, river discharge volumetric flow rate, and river mouth morphology. A field experiment was carried out in the Columbia River to test the hypothesis that the estuarine salt wedge is acoustically observable in terms of low-to-mid-frequency acoustic propagation. Linear frequency-modulated (LFM) acoustic signals in the 500-2000 Hz band were collected during the advance and retreat of the salt wedge. Data-model comparisons demonstrate the degree to which acoustic propagation in this constrained environment is controlled by horizontal refraction and out-of-plan scattering by bedforms along the acoustic transect.
Marine mammal hearing and the effects of noise
Authors: Southall Brandon L.
Published: November 2016

Marine mammals use sound for critical life functions through passive listening and, in some species, active sonar. Major recent advances have been made in understanding what sounds they make, how they hear, and how noise affects their hearing, behavior, and physiology. While data are lacking for whole groups, notably baleen whales, direct hearing measurements are available for most taxa. Some species, such as odontocete cetaceans, hear extremely broad frequency ranges, well into ultrasonic biosonar frequencies. Pinnipeds have more limited frequency ranges but are adapted for aerial and underwater hearing. Indirect data suggest whales use and are more sensitive to low frequencies. For most species, quite high received sound levels are required to temporarily or permanently affect hearing. Direct experimental measurements of behavioral responses have revealed strong species and context dependencies, with factors such as proximity, novelty, and spatial relationships influencing response probability as well as relative loudness. For active surveillance sonar systems operating in the 30-200 kHz range, whales and otariid pinnipeds are of much less concern in terms of audibility and potential behavioral disturbance than phocid pinniped and odontocete cetaceans, notably porpoises. Hearing loss or other injuries from such systems are quite unlikely in almost all practical scenarios.
Electronic shell―Improvement of room acoustics without orchestra shell utilizing active field control
Authors: Watanabe Takayuki , Miyazaki Hideo
Published: November 2016

This paper introduces an example of Electronic Shell acoustic enhancement system that was installed in a multi-purpose hall without an orchestra shell. The system is based on the concept of Active Field Control using electro-acoustic means. The three objectives of this system were 1) the enhancement of early reflection for performers, 2) the extension of the reverberation time and the enhancement of the total sound energy on stage, and 3) the enhancement of early reflection in the audience area. The application of this system showed an improvement of about 1 to 2 dB in STearly and more than 2 dB in G in the audience area, which is equivalent or better performance than simple mobile type orchestra shell. Regarding the spatial sound structure and the time domain characteristics between simple mobile type shell and the Electronic Shell system, there are differences since the mobile type shell mainly takes care of lateral reflections; on the other hand, the Electronic Shell system takes care of overhead reflections, and it cannot provide some early reflections after the direct sound arrives. It was clarified the relationship between the differences in physical features and the subjective improvement of the musical performance using a temporal system installed in a rehearsal hall.
Killer whale (Orcinus orca) audiograms
Authors: Branstetter Brian K. , Acton Doug , Stewart John , Houser Dorian , St. Ledger Judy , Finneran James , Jenkins Keith
Published: November 2016

Historically, understanding of killer whale (Orcinus orca) hearing was based on behavioral and evoked potential data from three animals, one of which had significant hearing loss. For the other two whales, the mean detection threshold at 20 kHz was 36 dB re 1 μPa; this is the lowest underwater behavioral detection threshold of any marine mammal tested, suggesting that it may be an outlier. The current study measured the behavioral audiograms of eight killer whales at two different facilities. Hearing sensitivity was measured from 100 Hz to 160 kHz in animals ranging in age from 12 to 52 years. Two whales had hearing loss consistent with presbycusis and a third displayed atypical low-frequency hearing loss (but normal high frequency hearing); previously measured low thresholds at 20 kHz were not replicated in any animal. Hearing in the killer whales was generally similar to other delphinids, with lowest threshold (49 dB re 1 μPa) at approximately 40 kHz, good hearing (i.e., within 20 dB of best sensitivity) from 5—80 kHz, and low- and high-frequency hearing cut offs (> 100 dB re μPa) of 600 Hz and 114 kHz, respectively.
Analysis of fin whale vocalizations south of Rhode Island
Authors: Giard Jennifer L. , Tazawa Makio , Miller James H. , Potty Gopu R. , Lin Ying-Tsong , Newhall Arthur , Baumgartner Mark
Published: November 2016

Fin whale vocalizations were recorded south of Rhode Island during late summer through early fall of 2015 using a number of underwater recording systems. These systems were deployed to monitor broadband noise, including pile driving, from construction of the Block Island Wind Farm. Two vertical hydrophone array moorings were deployed in approximately 40 meters of water each with four hydrophones. Additionally, a tetrahedral array was deployed in about 30 meters of water just above the seabed. The tetrahedral array consisted of four hydrophones spaced 0.5 meters apart. The spacing between each of these recording systems was approximately 7.5 km. 20-Hz fin whale vocalizations were recorded numerous times on all of the sensors both during and after construction was completed. An analysis and localization effort of these signals was performed to estimate the source level, directionality, and the track of the whale over the period of the vocalizations. The results of this analysis will be discussed. [Work supported by the BOEM.]
Improvements to using inter-click intervals to separate odontocete click trains from multiple animals
Authors: Young Jeremy , Høst-Madsen Anders , Nosal Eva-Marie
Published: November 2016

At the December 2013 ASA meeting, we introduced a method to separate click trains from multiple odontocetes that relies on click timing only. The method assumes that ICIs are slowly-varying according to some distribution. Click trains are classified by sequentially going through the clicks and maximizing the likelihood based on these distributions. Since then, additions have been made to improve performance and make it more practical including a source number estimation method, a refinement to the algorithm when the ICI distributions are unknown, and a way to incorporate information from the shape of clicks. We will present the results of these new methods on real and simulated datasets.
Monitoring of swine sneezing using time-frequency analysis for detecting diseases
Authors: Kawagishi Takuji , Mizutani Koichi , Zempo Keiichi , Wakatsuki Naoto , Takemae Nobuhiro , Saito Takehiko
Published: November 2016

This research mentions a detection method of swine sneezing in noisy swine house. While it is important to prevent swine infectious disease expansion in early stage, it is difficult to detect an infection in early stage because we cannot judge an infection from appearance of swine. However, it is a well-known fact that a swine with an infection tends to sneeze much more than healthy swine. The aim of this research is to achieve a detection of diseased swine in an automated way using the sound in the swine house and signal processing. We found that the sound of swine sneeze includes high frequency components 5-30 kHz and a sound feature of spectra, compared to the environmental noise in swine house. Based on these features of sneezing sound, we propose the detecting technique of sneezing sound based on the composition template of a frequency feature by a time-frequency analysis which is calculated from a lot of sneezing sounds. This method calculates the difference between frequency values of templates and recorded sounds. That could judge the recorded sounds as sneezing if sounds are smaller than the threshold. As a result, the method demonstrated effectiveness in a detection of swine sneezing.
Age-related hearing loss in TrpV1 knockout mice
Authors: Li Hongzhe
Published: November 2016

Several transient receptor potential (TRP) channels including TRPV1 are located on hair cell membranes. The gating mechanisms of these channels are associated with cellular stress, inflammation, and cytoplasmic uptake of aminoglycosides. Thus, TRPV1 channel may serve as a functional target that links acoustic trauma and enhanced aminoglycoside trafficking. TrpV1 mutant mice have no apparent hearing loss as young adults. Here, we assessed the hearing sensitivity of TrpV1 mutant mice (B6.129X1-Trpv1tm1Jul/J, stock #3770) by auditory brainstem responses to a broad frequency range, from 4 to 48 kHz. At 7 weeks of age, the auditory sensitivity in TrpV1 mutant mice was comparable to their heterozygous littermates. By 11 weeks of age, mutant TrpV1 mice exhibited evident high frequency hearing loss, with 30-to-40 dB elevated thresholds between 24 and 48 kHz, compared to littermate controls. At 18 weeks of age, high frequency hearing sensitivity worsened in both groups of mice, and this age-related progressive hearing loss was further expedited in TrpV1 mutant mice compared to littermate controls. Further research is required to determine the otoprotective role of TRPV1 channel in maintaining auditory sensitivity as mice age, and whether TrpV1 functionality exacerbates aminoglycoside-induced ototoxicity.
Tissue physical property in the head of small toothed whales: Effect on the clicks propagation and directivity
Authors: Kuroda Mika , Sasaki Motoki , Yamada Kazutaka , Miki Nobuhiro , Amano Masao , Yamada Tadasu K. , Matsuishi Takashi
Published: November 2016

In the current study, the distribution of acoustic impedance in the head of harbor porpoise and striped dolphin were reported and the transmission factor in the head was calculated. Clicks properties are considered to be closely connected to the structure of sound producing organ, however, few effective investigations have been carried out to reveal the cause of the species diversity of clicks properties. Clicks of toothed whales has been confirmed to be produced at the dorsal barsae (DB) and propagated to the melon where the clicks’ beam is progressively focused, and emitted into the seawater from the emitting surface (ES), a circular aperture at the frontal part of the melon. In our observation of the melon, a continuous gradients were observed from DB to ES for three species. At the ES, acoustic impedance of melon was matched with that of seawater. This mechanism would enable efficient click propagation and emission. The estimated directivity of clicks only from the transmission factor was much weaker than observed directivity, which suggests that the directivity of clicks is strongly affected by the refraction in the melon than a reflection and attenuation in the head tissue.
Variation in frequency-modulated call type for different flight densities in Mexican Free-tailed bats
Authors: Mardis Cassi , Dreessen Stephanie , Kloepper Laura
Published: November 2016

Mexican free-tailed bats (Tadarida brasiliensis) adapt their call type depending on multiple factors. These bats have two general types of echolocation sounds, frequency-modulated (FM) and constant frequency (CF). CF calls are generally produced during the search phase of foraging, and FM calls are used during approach, prey capture, and roost emergence. In this study, we examined how Mexican free-tailed bats adapt their calls during emergence to avoid echo interference. We extracted individual calls from within a 500-ms sample that corresponded to five different emergence density categories. We found that these bats produce eight different FM call types during emergence. For each call within the sample, we characterized the call shape and calculated different parameters (duration, start frequency, peak frequency, end frequency). We compared the acoustic parameters across density categories and call shape, and compared the distribution of call shape across density categories. The results indicate that the call parameters and call shape vary from bat to bat, but there is no clear trend that this variance is due to the bat density. Therefore, these bats are likely changing their call shape and frequency characteristics to distinguish their own echoes from those of other bats.
Localization of acoustic windows in the beluga by acoustic delays from different sound-source positions
Authors: Sysueva Evgeniya , Supin Alexander , Popov Vladimir , Nechaev Dmitry , Lemazina Alena , Tarakanov Mikhail
Published: November 2016

Acoustic windows were localized by acoustic delays from different sound-source positions in a beluga whale (Delphinapterus leucas). The delays were measured by recording the earlies component of the auditory evoked potential (AEPs) to short tone pips. This component recorded from the lateral head surface reflects the activity of the auditory nerve and features true monaural properties. Monaural nature of the component allows to localize an acoustic window with a better precision than binaural components. The acoustic delays were measured from a sound source at different positions at frequencies from 22.5 to 90 kHz (half-octave steps).A common sound-receiving region was identified for all these frequencies. The relation of the results to hypotheses of sound conduction in odontocetes is discussed. The use and care of the animals were adhered to the guidelines of the Russian Academy of Sciences for Research Involving Human and Non-Human Animals.
Three dimensional observation of pelagic fish schools by multibeam echosounder ME70
Authors: Abe Koki , Matuura Tomohiko , Yasuda Tohya , Kawauchi Yohei
Published: November 2016

In this study, three-dimensional observation of pelagic fish using a multibeam echosounder with a quantitative echosounder are discussed. Multibeam echosounder originally has been developed for bathymetry survey, transmits and receives fan-shaped acoustic beam, and has extensive search area compared with single beam conventional echosounder. SIMRAD ME70 used in this study was developed specifically for fisheries research while maintaining the characteristics of fan-shaped wide multibeam. Because the calibration software is built in the ME70 for quantitative analysis of the acoustic beams, the output data can be compared with that from the quantitative echosounder like the EK60. Therefore, the ME70 and the EK60 are installed in the R/V YOKO-MARU used in alternate transmission, and carried out the observation for the same fish schools. Echograms were obtained from both echosounders and compared in terms of differences in characteristics of these echograms. Multibeam echosounder covered a widespread area to the side way of the vessel that the conventional echosounder could not observe and allowed to express fish schools in three dimensions.
Modelling macroalgae scattering (Ecklonia radiata)
Authors: Hermand Jean-Pierre
Published: November 2016

This paper will discuss the numerical modelling of acoustic scattering by macroalgae. Using earlier measurement of tissue acoustic properties, the scattering function of a thalus of Ecklonia radiata species is estimated by means of finite elements. Results will be presented for frequencies up to 20 kHz. [Work supported by ONR and ONR Global.]
Clinical experience of intra-operative high intensity focused ultrasound in patients with colorectal liver metastases. Results of a Phase II study
Authors: Melodelima David , Dupre Aurelien , Perol David , Chen Yao , Vincenot Jeremy , Kocot Anthony , Rivoire Michel
Published: November 2016

The aim of this study was to assess the feasibility, safety and accuracy of HIFU ablation in patients with liver metastases in a prospective, phase I-II trial. The transducer has a toroidal shape (diameter: 70 mm, radius of curvature: 70 mm) and was divided into 32 ring-shaped emitters operating at 3 MHz. Twenty-eight patients were included. HIFU ablations were created to ablate metastases (20 mm maximal diameter) with safety margins in all directions. The exposure time varied from 40 seconds to 370 seconds according to the diameter of the metastases to be treated. One metastasis of 10 mm in diameter was ablated in 40 seconds with safety margins. Using electronic focusing metastases of 2 cm in diameter were ablated with safety margins (> 3 mm in all directions) in 370 seconds. The dimensions of these HIFU ablations were a diameter of 48 ± 4.9 mm and a long axis of 51 ± 3.4 mm. No damage occurred to neighboring tissues. This HIFU device safely achieved ablations of small metastases (< 20 mm) with planned safety margins of at least 3 mm in all directions. This study is the first clinical use of intra-operative HIFU in patients with liver metastases.
Liver tracking system utilizing template matching and energy function in high intensity focused ultrasound/radio frequency ablation therapy
Authors: Tomita Kyohei , Koizumi Norihiro , Kondo Ryosuke , Kayasuga Atsushi , Nishiyama Yu , Tsukihara Hiroyuki , Fukuda Hiroyuki , Numata Kazushi , Matsumoto Yoichiro , Mitsuishi Mamoru
Published: November 2016

Monitoring and evaluating the therapeutic effects, in ultrasound images during HIFU (High Intensity Focused Ultrasound) and RFA (Radio Frequency Ablation) therapies, are important. However, the common problem is the difficulty to monitor the progress and identify the positions of the focal lesion precisely in accordance with the progress of the treatment. This problem is caused by the movement of organs and the change of the textures information in ultrasound images. To overcome those problems, we have developed a novel method to track, follow, and monitor the focal lesion by the combination of the energy function method and the template matching method. The template matching method uses the characteristic texture information of the organ near the focal lesion. The energy function is implemented in order to reinforce the robustness of the tracking performance of the template matching method. Particularly, we evaluate the existing probability of the focal lesion considering the continuity of the movement and the relative distance from the surface of the liver. The estimated position of the focal lesion is obtained by minimizing the above mentioned energy function. The effectiveness of the proposed method is confirmed by comparing the novel proposed method and the conventional template matching method in terms of the tracking performance for the liver tumor during the real RFA treatments.
Construction methodology for non-invasive ultrasound theragnostic system by medical digitalization
Authors: Koizumi Norihiro , Tsukihara Hiroyuki , Yoshinaka Kiyoshi , Miyazaki Hideyo , Fukuda Hiroyuki , Numata Kazushi , Homma Yukio , Matsumoto Yoichiro , Mitsuishi Mamoru
Published: November 2016

We propose a noninvasive ultrasound theragnostic system (NIUTS) that compensates for movement by tracking and following the area to be treated by using stereo ultrasound imaging while irradiating the focal lesion with HIFU. Theragnostics involves therapeutics and diagnostics. Our proposed system uses focused ultrasound to destroy tumors and stones without damaging the surrounding healthy tissue. This is achieved by tracking and following the focal lesion (stones/tumors), in order to compensate for movement due to respiration, heartbeat, etc. In the overall research project, we aim to enhance the focal lesion servo (FLS) performances based on our original medical support system construction methodology, which is called “Me-DigIT (medical digitalization by IT technology, which includes especially robot technology).” In the present report, we illustrate the mechanisms, controllers, and robot vision core technology to enhance the focal lesion tracking and following performance of the NIUTS. As a result, with the constructed NIUTS, tracking performance within 2.5 mm was achieved for a healthy human kidney. The standard deviation of the position of the servo target was 1.92 mm with FLS, while it was 13.2 mm without FLS. In other words, 86 % of body movement could be compensated for by using NIUTS.
Modeling shock-wave fields generated by a diagnostic-type transducer
Authors: Karzova Maria M. , Rosnitskiy Pavel B. , Yuldashev Petr V. , Sapozhnikov Oleg A. , Kreider Wayne , Cunitz Bryan W. , Bailey Michael R. , Khokhlova Vera A.
Published: November 2016

New applications of ultrasound imaging may benefit from increased in situ pressure levels. However strong nonlinear propagation effects have not been studied in detail for fields generated by diagnostic transducers. Here we compare two modeling approaches for predicting shock formation in fields generated by a curvilinear imaging probe (C5-2). The field was simulated in two ways: 1) a 3D full-diffraction model based on the Westervelt equation, with a boundary condition defined on a cylindrical surface; 2) an axially symmetric parabolic model based on the KZK equation to define a flat, circular equivalent source. For both models, boundary conditions are adjusted to match low-power axial pressure measurements in the focal lobe of the beam. Simulations and measurements were performed for operation of 40, 64, and 128 central probe elements, and a wide range of clinically relevant output levels was considered. Comparison of focal waveforms shows that the KZK model can predict the amplitudes of fully developed shocks within 5% for 64 and 128 active elements, and within 15% for 40 elements. The full 3D calculations provide better agreement with experiments (within 3%) but require significantly more computational resources. [Work supported by RSF 14-12-00974 and a scholarship of the president of Russia.]
Three-dimensional sound field reproduction based on spatial fusion of carrier and sideband waves with parametric array loudspeaker
Authors: Nakayama Masato , Nishiura Takanobu
Published: November 2016

It is very important to provide a personal audible space (audio-spot) to listeners. Parametric array loudspeaker (PAL) has been proposed in order to provide an audio-spot because it has super directivity. It however has difficulty in reproducing the audible sound only to the particular space because the acoustic beam with the PAL is reflected and intercepted. Therefore, we have proposed the three-dimensional sound field reproduction based on spatial fusion of carrier and sideband waves with the PAL. In addition, we have proposed the method of near-sound-field reproduction based on spatial fusion of the carrier and sideband waves. In this presentation, we explain principle of the proposed method, and its applications. In the proposed method, we utilize principle which the intense ultrasound self-demodulates to the audible sound by nonlinear interaction in the air. More specifically, the intense ultrasound consists of the carrier and sideband waves, and the audible sound is demodulated as the different tone between carrier and sideband waves. The proposed method forms the audio-spot by fusing the carrier and sideband waves in the particular space. Finally, we evaluate the effectiveness of the proposed method through the evaluation experiments.
Perceptual optimization of sound field reproduction system and sound field rendering with software/hardware-based acoustic simulation
Authors: Otani Makoto , Tsuchiya Takao , Iwaya Yukio , Inoguchi Yasushi
Published: November 2016

The performance of sound field reproduction based on integral equations is restricted by interval of boundary surface discretization, which would cause spatial aliasing when it is not sufficiently fine. Physically accurate reproduction without spatial aliasing throughout an entire audible frequency range would require impractically large number of discretization points. However, the requirement would be relaxed if perceptually satisfactory reproduction is possible even with spatial aliasing. In this presentation, first, we introduce results of perceptual evaluation of effects of spatial aliasing in the sound field reproduction on auditory perception in order to find out a reasonable requirement for realization of perceptually satisfactory system. Second, we introduce development of sound field rendering system consisting of the sound field reproduction system and FDTD (Finite Difference Time Domain) method as an acoustic simulation solver. Finally, we also introduce our attempt to develop a real-time sound field rendering system that utilizes hardware-based acoustic simulation using DHM (Digital Huygens Model) implemented in ASIC (Application Specific Integrated Circuit).
Cancellation, reproduction, and cloaking using sound field control
Authors: Cheer Jordan
Published: November 2016

The active control of sound fields has been applied in active noise cancellation, sound field reproduction, and active acoustic cloaking; however, relatively few studies have considered the relationship between these three areas of research. This paper investigates the physical limitations on active noise control, sound field reproduction, and active acoustic cloaking in terms of the controllability and observability of the sound field. This has been achieved through a series of simulations that consider the control of the sound field in the presence of a scattering object. In terms of the controllability problem, it is shown that while active noise control and sound field reproduction are most effective when considering the interior control problem, active acoustic cloaking is most effective when facing the exterior control problem. Different sensing strategies are then considered for the cancellation, reproduction, and cloaking problems and their impact on the observability of the control problem is discussed.
Detached eddy simulation of a highlift airfoil noise with spectral difference method
Authors: Gao Junhui , Li Xiaodong
Published: November 2016

In this study the noise generated by the 30P30N highlift airfoil is simulated with a high order computational aeroacoustics code. To handle the complex geometry of the airfoil, the high order spectral difference method based on unstructured mesh is used for spatial discretization. The multi-time-step method based on Adam-Bashforth scheme is utilized for time marching, and a speed-up ratio greater than 10 is obtained comparing with the single time step method. The detached eddy simulation method is conducted for turbulence modeling. Radiation and outflow non-reflective boundary conditions are used in the far field and downstream. In this simulation, the inflow Mach number is 0.17, and the Reynolds number based on the inflow velocity and the chord length of the airfoil is 1.7e6. Three attack angles, which are 4, 5.5, and 8.5 degrees, respectively, are considered in this study. The dynamic pressure on the surface of the slat is sampled and compared with the experimental data by other researchers, and a good agreement is obtained. The far field noise, computed with the permeable Ffowcs Williams-Hawkings (FW-H) integration method, is analyzed and compared with the experimental data. The noise source is analyzed and identified with a correlation analysis of the dynamic pressure on the slat and the near field noise.