bluuebunny/crossref_metadata_2025 huggingface dataset:
Apparent-time study of interdental-stopping among English-monolingual Finnish- and Italian-heritage Michiganders
Authors: Cornillie Paige , Fosgard Julianne , Gibbs Samantha , Griffin Delani , Lawson Olivia , Rankinen Wil A.
Published: June 2017

The production of coronal oral stops in place of interdental fricatives, referred to as interdental-stopping, has been documented in Michigan’s Upper Peninsula (UP) [3, 2], as well as, in other ethnic-heritage influenced English varieties. However, there is a lack of quantitative inquiry into the degree to which this salient feature is present among Michigan UP's now predominantly monolingual English-speaking communities; recent studies have focused primarily on the last remaining older-aged bilinguals [1]. Michigan’s UP is in an ideal position to examine to what extent this feature is present among a rural and predominantly monolingual English-speaking community. The present study examines 40 Finnish-Americans and 44 Italian-Americans, whom are all monolingual speakers from Michigan’s Marquette County. Both samples are stratified by age, sex, and socioeconomic status. All data are obtained from a passage task. To what degree, if any, does stopping occur among the Finnish- and Italian-heritage monolingual-English speaking communities? This study reveals interdental-stopping occurring most often among working-class males but least among Italian middle- and younger-aged groups. The study's apparent-time construct highlights a potential change in the covert prestige that has been typically associated with this feature among the older generation [1]. The decrease of interdental-stopping among the younger generation indicates a shift in the feature's prestige within the community.
Localization and source assignment of blast noises from a military training installation
Authors: White Michael J. , Nykaza Edward T. , Hulva Andrew
Published: June 2017

Time differences of arrival (TDOA) are often sufficient data for localization of a sound source with a sensor array. We consider the problem of localizing multiple impulsive sound sources that occur on a military installation having live-fire training exercises, using a dozen or more noise monitors as a large array. In this setup, though, sounds from multiple events can arrive in different order at different monitors. When multiple sources are operating, ambiguous source-detection assignments degrade the localization estimates. By minimizing a global cost-function on the entire detection catalog, we resolve source-detection assignments and improve the localizations. We outline an estimator and show results with simulated data and field measurements.
DOA (direction of arrival) estimation of incident sound waves on a spherical microphone array: Comparison of some correction methods proposed to solve the DOA bias
Authors: Embrechts Jean-Jacques
Published: June 2017

A spherical 16-microphones array has been designed and built for room acoustics applications (measurement of directional room impulse responses or DRIR). The identification of strong specular reflections in a DRIR requires an accurate determination of their direction of incidence on the sphere. Beamforming methods are therefore applied for their DOA (direction of arrival) estimation. However, the crude applications of these methods revealed significant deviations between the measured and expected DOA. In-depth experiments in anechoic conditions have been carried out to analyze this problem and they revealed that the origin of these deviations could be related to the non-rigidity of the spherical surface of the array. In these experiments, incident waves were generated by a pseudo—point source at several frequencies in the anechoic chamber. The microphone array is rotated and oriented at several azimuthal positions. The sound pressures measured on the sphere by the 16 microphones are then compared with their theoretical values obtained with a rigid sphere assumption, which revealed some differences. Some methods are then proposed to correct this problem. These methods are finally presented and their results in DOA estimation tasks are compared.
Single channel speech enhancement based on harmonic estimation combined with statistical based method to improve speech intelligibility for cochlear implant recipients
Authors: Wang Dongmei , Hansen John H. L.
Published: June 2017

In this study, we propose a single microphone speech enhancement algorithm by combining harmonic structure estimation and traditional MMSE speech enhancement for a leveraged overall solution. Traditional single channel speech enhancement methods are usually based on the statistic characteristics of noise signals which are effective only for stationary noise, but not for non-stationary noise. In our study, we attempt to estimate noise by exploring the harmonic structure of the target speech combined with temporal noise tracking. In voiced segments, since speech energy is sparsely carried by harmonic partials, the spectrum located between adjacent harmonic partials are considered as noise. We assume that the speech spectrum distributes continuously along the frequency-dimension. Thus, the noise overlapped with speech harmonics can be estimated with an interpolation technique. Next, the estimated noise is incorporated into a traditional MMSE framework for speech enhancement. A listening test is carried out with 6 cochlear implant recipients to evaluate the proposed speech enhancement algorithm. The experimental results show that the proposed algorithm is able to improve the speech intelligibility in terms of word recognition rate for CI listeners.
Reliable data delivery using packet coding over acoustic links
Authors: Ahmed Rameez , Stojanovic Milica
Published: June 2017

Acoustic links are challenged by high bit error rates, which cause data packets to be declared as erroneous. To prevent the packet loss and achieve reliable data transmission over such links, some form of feedback must be implemented to deliver acknowledgments from the receiver to the transmitter, thus initiating re-transmission of erroneous packets. Conventionally, data packets are grouped and a selective acknowledgment procedure of the stop-and-wait type is employed as a suitable solution for half-duplex acoustic links. We re-visit the issue of reliable data transmission and investigate the use of random packet coding in conjunction with a selective acknowledgment procedure. Specifically, we introduce random packet coding, and regard a block of coded packets as an equivalent of a packet—now termed the super-packet. We then form groups of super-packets and apply a selective acknowledgment procedure on the so-obtained units. Analytical results, obtained with experimentally verified channel models, demonstrate the power of grouped packet coding which offers a much improved throughput-delay performance on randomly time-varying acoustic channels with long delays.
Very low signal to noise ratios coherent communications with an M-ary orthogonal spread spectrum signaling scheme
Authors: Silva Jacob L. , Gendron Paul J.
Published: June 2017

Considered here is the use of an M-ary orthogonal spread spectrum signal set for coherent symbol detection at very low signal to noise ratios (SNR). We consider symbols that are convolutionally orthogonal over the entire multipath delay spread of the channel and allow for the minimum mean square error (MMSE) estimation of an observed acoustic response function with minimal computational effort at the receiver. We employ these signals with an assumed sparsity prior to implement a joint symbol and broadband channel estimation scheme for coherent detection without the use of intra-packet training symbols of any kind. The approach allows us to compensate for the shared time varying Doppler process of the various coherent arrivals. The approach is demonstrated with at-sea recordings at extremely low received SNR.
Broadband underwater acoustic communications subsystem design
Authors: Bachand Corey , Turcotte Tyler , Brown David A.
Published: June 2017

Increased bandwidth for acoustic communication places demanding requirements on the electroacoustic transducer, tuning and matching circuits, and amplifier design. This presentation investigates various aspects of the transmit channel with a focus on increasing bandwidth to the fullest extent possible. This includes using alternative transducer designs, polarization orientations, transduction materials, broadband tuning networks, and gain/phase control in high efficiency Class-D amplifiers. Comparisons between modeled and measured performance for systems that achieve 10, 20, and 30 kHz are considered.
Underwater source localization using unsynchronized passive acoustic arrays
Authors: Zitterbart Daniel P. , Lin Ying-Tsong
Published: June 2017

Localizing sources of underwater sound is a well studied field that is utilized by several scientific and naval communities. The scope of localization might differ dramatically, from the necessity to localize targets with a sub-meter accuracy to estimation of the position of an object on a kilometer scale. Advances in data storing capabilities during the last decade now allow multi-year deployments of autonomous passive acoustic monitoring arrays for which past-recovery time synchronization cannot be guaranteed. For localization of transient signals, like marine mammal vocalization, arrival time based localization schemes are currently the prevalent method. Applying arrival time based methods to non-synchronized multi station arrays eventually leads to large localization uncertainties. Here, we present a backpropagation based localization scheme that overcomes the necessity to synchronize between array stations for localization purposes. It utilizes waveguide dispersion measured within distributed arrays for simultaneous source localization and time synchronization. Numerical examples are presented to demonstrate that localization uncertainty significantly improves compared to arrival time based methods.
Estimation of clock drift in underwater acoustic instruments using propagation channel analysis
Authors: Udovydchenkov Ilya A. , Blair Ballard J. , Stephen Ralph A. , Worcester Peter F. , Dzieciuch Matthew
Published: June 2017

All underwater acoustic sensors require accurate on-board clocks for subsequent data analysis and interpretation. Unfortunately, most clocks suffer from a phenomenon called “clock drift” (loss of accuracy), which occurs due to environmental changes, aging, and other factors. Typically, the clock drift is accounted for by calibrating the clock in the instrument before and after the deployment, and applying a correction during data post-processing. This method, however, does not allow accurate estimation of clock errors during a particular experimental event. In this presentation a small subset of data collected on the last day of the Bottom Seismometer Augmentation in the North Pacific (OBSANP) Experiment in June-July 2013 is analyzed. It is shown that advanced signal processing techniques can be used to accurately reconstruct the motion of the ship-suspended acoustic source, which, in turn, can improve the accuracy of the acoustic receivers deployed on the seafloor in the deep ocean. [Work supported by the MITRE Innovation Program and ONR.]
Covet underwater acoustic communication based on spread spectrum orthogonal frequency division multiplexing (OFDM)
Authors: Yang Shaofan , Guo Zhongyuan , Guo Shengming , Jia Ning , Xiao Dong , Huang Jianchun
Published: June 2017

A covert underwater acoustic communication (UAC) method is realized with a dolphin whistle as the information carrier. The proposed method jointly utilizes the spread spectrum and orthogonal frequency division multiplexing (OFDM) techniques. The original dolphin whistle is represented as the complex baseband OFDM transmitted signal and the phase of its discrete Fourier transform (DFT) coefficients are modulated by a spread spectrum code to carry information. The audio quality and waveform similarity are used as two covert effect criterion. In simulations, the influences of the code length and modulation parameters are investigated. It is verified that the communication performance and camouflage effect are a pair of contradictions. Therefore, the best compromise formula should be chosen according to the actual demands.
Specifics of DEMON acoustic signatures for large and small boats
Authors: Pollara Alexander S. , Lignan Gregoire , Boulange Louis , Sutin Alexander , Salloum Hady
Published: June 2017

Marine vessel propellers produce noise by the formation and shedding of cavitation bubbles. This process creates both narrow-band tones and broad-band amplitude modulated noise. The Detection of Envelope Modulation on Noise (DEMON) is an algorithm to determine the frequencies that modulate this noise. Results of DEMON processing depend on the selection of a ship noise frequency band to analyze. It is well known that the best passband to use may vary dramatically between vessels. Despite this, there has been no systematic investigation how the DEMON spectra depend of the carrier noise frequencies, and the modulation indices of vessel noise have not been investigated. We use a modification of the Cyclic Modulation Spectrum (CMS) to determine the modulation index of cavitation noise across the entire spectrum of carrier frequencies. We investigated how speed and vessel size affect the modulation index and carrier frequency of vessel noise. Several phenomena in the distribution of modulation indices for large and small boats were observed. These can be used for vessel classification. For small boats, the DEMON spectra have a different set of frequency peaks at various carrier frequencies. This is explained by the engine exhaust which produces amplitude modulated noise much like a propeller.
The underwater sound field from impact pile driving: Observations and modeling of key features in the time domain
Authors: Dahl Peter H. , Dall'Osto David R.
Published: June 2017

Observations of the pressure time series made from a vertical line array at range of order 10 waveguide depths from the pile source are presented along with interpretive modeling. Modeling is based on conceptualizing underwater sound from impact pile driving as originating from a vertical distribution of harmonic point sources uniformly distributed along the wetted-length of the pile, each source phased prior to summation in the frequency domain. This leads to credible representations of pressure time series as function of range and depth that are linearly related to field measurements. In particular, precursor arrivals which arrive prior to any water borne arrival as result of having propagated through a higher-speed sediment, and deterministic manifestations of the Mach cone effect within the main pressure time series, are shown in comparison with modeling results. Both phenomena are influenced by the increasing sediment excursion of the pile, and the importance of the sound speed gradient and sediment attenuation to the precursor will be shown. Finally, the synthetic results are used to generate acoustic streamlines that trace the pathway of (short-time-averaged) active acoustic intensity associated with the precursor. Results from this work suggest the precursor amplitude sets the performance bound of any sound mitigation strategy.
Experimental validation of models for prediction of marine pile driving sound
Authors: Müller Roel A. , Nijhof Marten , Binnerts Bas , de Jong Christ A. , Ainslie Michael A. , Jansen Erwin
Published: June 2017

Various models for the underwater noise radiation due to marine pile driving are being developed worldwide, to predict the sound exposure of marine life during pile driving activities. However, experimental validation of these models is scarce, especially for larger distances. Recently, TNO has been provided with data from underwater noise measurements up to 65 km from the piling location, gathered during the construction of two wind farms in the Dutch North Sea. These measurement data have been compared with different modeling approaches, in which the sound source is either formulated as an equivalent point source, or as a axially symmetric finite element model of the pile including the surrounding water and sediment. Propagation over larger distances, with varying bathymetry, is modeled efficiently by either an incoherent adiabatic normal mode sum or a flux integral approach. Differences between simulation and measurement data are discussed in terms of sound exposure level and spectral content, which leads to more insight into the mechanisms of sound radiation and propagation that are relevant during marine piling activities. An overview is given of the merits, shortcomings, and possibilities for improvement of the models.
Hydroacoustic measurements and modeling of pile driving operations in Ketchikan, Alaska
Authors: Warner Graham A. , Austin Melanie , MacGillivray Alexander
Published: June 2017

Underwater acoustic measurements of pile driving operations were made at the Ketchikan ferry terminal in July 2016. At the time of the measurements, marine mammal injury and disturbance criteria developed by the National Marine Fisheries Service (NMFS) were based on sound pressure level (SPL) thresholds. Shortly after the measurements, NMFS changed the injury thresholds to a dual criteria involving peak pressure and sound exposure levels specific to marine mammal functional hearing groups. This paper presents distances to both injury criteria and the (unchanged) SPL-based disturbance criteria for vibratory driving and impact hammering 30-inch diameter cylindrical piles. Threshold distances were obtained using empirical regressions of sound levels measured by seabed-mounted recorders at 10 and 1000 m nominal range. A finite-difference method pile driving source model was used with a parabolic equation propagation model to compare measurements with simulations and to estimate received levels at all ensonified locations in the complex bathymetric environment of the Tongass Narrows. Measured and modeled results show the importance of hydrophone placement with respect to the Mach cone and near-pile bathymetry.
On the airborne contribution to the underwater sound-field from marine pile installation
Authors: Dall'Osto David R. , Dahl Peter H.
Published: June 2017

Airborne sound generated by the impact hammer used for marine pile installation contributes to the total underwater sound field. This contribution is distinct from the sound generated underwater, e.g., by the up-and-down going Mach waves generated by the pile underwater. Airborne sound transmission into the water occurs within a 26 deg. cone directly below the pile-hammer. As the pile is driven deeper, the distance between the hammer and the water surface decreases producing a time-dependent signature in the observed underwater sound pressure that correlates directly to the observed pile-depth monitored during installation. Additionally, the area subtended by the cone of transmission decreases as the pile is driven deeper, which reduces the duration of the air-borne contribution which is longest at the beginning of the pile installation. In this presentation, a model for the airborne contribution is examined alongside data that was measured at ranges of approximately 2 and 10 times the water depth. In addition to basic interpretation of the time signature from impact pile driving, the observed transmission of high-intensity airborne sound into the water during pile installation has implications for the contributions of airborne noise associated with wind-turbines.
Overview of underwater acoustic and seismic measurements of the construction and operation of the Block Island Wind Farm
Authors: Miller James H , Potty Gopu R. , Lin Ying-Tsong , Newhall Arthur , Vigness-Raposa Kathleen J. , Giard Jennifer , Mason Tim
Published: June 2017

The Block Island Wind Farm (BIWF), the first offshore wind farm in the United States, consists of five 6-MW turbines 3 miles southeast of Block Island, Rhode Island in water depths of approximately 30 m. Construction began in the summer of 2015 and power production began in late 2016. Underwater acoustic and geophysical measurement systems were deployed to acquire real-time observations of the construction and initial operation of a wind facility to aid the evaluation of environmental effects of future facilities. The substructure for these BIWF turbines consists of jacket type construction with piles driven to the bottom to pin the structure to the seabed. The equipment used to monitor construction and initial operation consisted of a towed array consisting of eight hydrophones, two fixed moorings with four hydrophones each and a fixed sensor package for measuring particle velocity. This sensor package consists of a three-axis geophone on the seabed and a tetrahedral array of four low sensitivity hydrophones at 1 m from the bottom. Additionally, an acoustic vector sensor was deployed in mid-water. Data collected on these sensor systems during construction and initial operation will be summarized. [Work supported by Bureau of Ocean Energy Management (BOEM).]
Hydroacoustic measurements during construction of the first US offshore windfarm—Methodologies to address regulatory requirements
Authors: Kalapinski Erik J. , Varnik Kristjan
Published: June 2017

The regulations governing underwater noise from offshore wind farm development in the United States have not been as explicit as in other countries. The Block Island Wind Farm represents the first case study. In this context, it is important to disseminate information about the relevant noise sources, address evolving guideline criteria, and develop noise measurement and analysis procedures to address regulatory reporting requirements. Tetra Tech led the hydroacoustic monitoring program which occurred in two distinct stages. The first involved short-term monitoring of the installation of the initial wind turbine generator foundation using both mobile real-time and static monitoring techniques used for daily reporting. Long-term monitoring of the remaining four foundations with static recorders documented the inherent variability in the data set. Received sound levels measured at pre-determined distances were used to assess site-specific propagation characteristics and to verify ranges to the relevant sound exposure thresholds. This involved the evaluation of multiple metrics including the apparent sound source level of pile-driving activities and the confirmation of the Exclusion and Monitoring Zone established to ensure the protection of marine life. All of the monitoring objectives were met, including the field verification of modeling results established during the environmental permitting process.
An integrated passive and active room acoustics + sound reinforcement system design solution for a large worship space
Authors: Kahn David
Published: June 2017

The United Methodist Church of the Resurrection, with more than 16,000 adult members and an average weekly worship attendance of more than 8,600, recently completed a new 3,500-seat worship space. The new sanctuary building has an ellipsoidal plan shape and a very tall ceiling to address an important programmatic goal to achieve “A Sense of Majesty”. Acoustical goals included warm speech throughout all seating areas with acoustics inspiring to create a high level of energy therefore encourage high level of participation. Furthermore, the church wants to support both traditional (orchestra and choir) and contemporary (Praise band with vocalists) styles of music in this new worship space. These programming goals, to some extent, are in conflict with one another. Particularly the architectural goal of having a soaring space is in conflict with the goals for a space that provides acoustical support of corporate worship. Since the walls and ceiling are too far away from most of the seating area to provide beneficial sound reflections to support corporate worship and to support traditional music, an electronic enhancement system was provided to electronically create the early sound reflections that could be created by a lower ceiling.
A loudspeaker orchestra for opera houses studies
Authors: D'Orazio Dario , Barbaresi Luca , Garai Massimo
Published: June 2017

A “Loudspeaker Orchestra” is an array of loudspeakers with a well-defined setup and layout. Initially proposed by contemporary composers for innovative performances (e.g., the “Acousmonium” used by the Groupe de Recherches Musicales in the 1970s), in the last years, the Loudspeaker Orchestra has been used for MIMO acoustic measurements in concert halls. In the present work, a Loudspeaker Orchestra for measurements in opera houses is proposed, taking into account the acoustic differences between a concert hall and an opera house. In fact, in a concert hall, the orchestra plays on the stage, while in an opera house, the orchestra plays in the pit, with a different layout, a smaller instrumental ensemble, etc. In a concert hall, the soloists are placed near the conductor, while in an opera house they move all over the stage, due to dramatic reasons. Basing on previous studies on room criteria and experiences with real orchestras, the authors proposed a Loudspeaker Orchestra layout for opera houses. In this work, tests on various configurations are presented, comparing measurements and numerical simulations.
Did Paleolithic cave artists intentionally paint at resonant cave locations?
Authors: Lubman David
Published: June 2017

In 1988, two investigators (Iegor Reznikoff and Michel Dauvois) reported a connection between the local density of cave paintings and local sonic “resonance” in three French Paleolithic painted caves. Archaeologist Chris Scarre summarized their findings in a brief article that drew much attention (Painting by Resonance, Nature 338 [1989]: 382). Scarre wrote “Reznikoff- Dauvois theory is consistent with the likely importance of music and singing in the rituals of our early ancestors.” Reznikoff-Dauvois believed cave artists intentionally chose painting locations for their sonic resonance. They further conjectured it was the artists admiration for resonant sound that inspired their choice. This writer suggests the associations found were merely correlative, and not necessarily causal. (Crowing roosters do not cause the sun to rise.) How then can the correlation be explained? This writer hypothesizes that initially, “painterly” needs rather than sonic preferences may have influenced choice of painting location (large expanses of non-porous rock). Since non-porous rock is highly sound reflective the best cave locations for long-lasting cave paintings are “resonant.” Paintings on porous (non-resonant) rock would not persist. This is a testable hypothesis. Moreover, combining impressive art and sound could inspire singing and dance. Such sites might plausibly become ritual spaces.
Synthetic aperture sonar interferometry for detailed seabed mapping: Performance considerations
Authors: Hansen Roy E. , Sæbø Torstein O. , Synnes Stig A. , Lorentzen Ole E.
Published: June 2017

Synthetic Aperture Sonar (SAS) interferometry is a technique for detailed mapping of the seabed, with the potential of very high resolution and wide swaths simultaneously. There are several specific challenges to overcome for the technique to reach its full potential. These differ from other mapping sensor technologies, e.g., multibeam echosounders (MBES), and interferometric sidescan sonars (ISSS). In this talk, we describe the principle of SAS interferometry with emphasis on the estimation part, strongly inspired by the similar principle in synthetic aperture radar (SAR). We describe the limiting factors in using SAS interferometry for seabed depth estimation. These are related to the host platform, the measurement geometry, the sonar array design, and the signal processing. We construct an error budget where we categorize the different components that affect the overall performance. We also describe the choices and tradeoffs available in the signal processing for a given set of measurements. We show example images and depth estimates from the Kongsberg HISAS interferometric SAS collected by a HUGIN autonomous underwater vehicle.
Coastal ocean current tomography using a spatio-temporal Kalman filter
Authors: Wang Tongchen , Zhang Ying , Yang Tsih C. , Xu Wen , Chen Huifang
Published: June 2017

The method of ocean acoustic tomography (OAT) can be used to invert/map the ocean current in a coastal area based on measurements of two-way travel time differences between the nodes deployed on the perimeter of the surveying area. Previous work has attempted to relate the different measurements in time using the Kalman filter. Now, if the ocean dynamics or model is known, one can also determine the current field given an initial distribution or the travel-time difference data on the boundary, and can even forecast the current changes. Based on the ocean dynamics, the current field is shown to be spatially and temporally correlated. We derive their relation and use that as the state model for the Kalman filter; the coefficients are estimated from data using an auto-regressive analysis. Armed with this model, it is shown based on simulated data that the current field can be tracked as a function of time using the Kalman filter (with an arbitrary initial condition) with a higher accuracy than that estimated by OAT. The reason of the improvement, the use of spatial-temporal state model (versus using only the temporal evolution), is studied. The method has also been applied to real data.
The International Electrotechnical Commission (IEC) and ultrasonics
Authors: Lanctot Peter J.
Published: June 2017

Peter Lanctot from the International Electrotechnical Commission (IEC) will provide an overview of the international standardization activities related to IEC Technical Committee 87, Ultrasonics. Since 1955, the IEC has published international standards for a wide range of applications across virtually all business sectors including medicine, electronics, consumer products, food, manufacturing industries, and defence for ultrasonic technologies. As TC 87 is in charge of Ultrasonic Standardization activities within the IEC, Peter will provide a high level overview on their standards work oriented towards ultrasonic aspects of medical equipment and the safety of non-medical applications of ultrasonic fields. He will also touch upon the important platform that IEC TC 87 and other IEC technical committees offer to companies, industries, and governments for meeting, discussing, and developing the International Standards they require. Based in Geneva, Switzerland, the International Electrotechnical Commission is the world’s leading organization that prepares and publishes International Standards for all electrical, electronic and related technologies.
Overview of International Electrotechnical Commission Technical Committee 87 ultrasound organization and standards
Authors: Maruvada Subha
Published: June 2017

The International Electrotechnical Commission (IEC) is the world’s leading organization that prepares and publishes International Standards for all electrical, electronic and related technologies. It comprises Technical Committees (TCs) and Subcommittees (SCs) that oversee standards development in all areas of technology. Particular to ultrasound medical devices, TC 87, Ultrasonics, is responsible for preparing standards related to measurement methods, field characterization, and safety concerns, but excluding safety and essential performance standards for equipment and systems. Responsibility for the latter falls under TC 62, Electrical Equipment in Medical Practice. SC 62B in TC 62 is in charge of all diagnostic imaging equipment and related devices, including ultrasound, and SC 62D deals with all electromedical equipment used in medical practice other than diagnostic imaging, such as ultrasound therapeutic and surgical devices. This presentation will discuss the safety standards, measurement standards, maintenance/performance documents and structure and distribution of work in TC 87 and SC62B and SC62D as an introduction to the more specific talks following.
International Electrotechnical Commission (IEC) and Food and Drug Administration (FDA) efforts to develop standards for ultrasound physiotherapy
Authors: Herman Bruce
Published: June 2017

Ultrasound physiotherapy devices produce acoustic energy, typically in the low MHz range, to generate deep heat for relief of pain and spasms, and have been used since the 1940’s. The IEC and the FDA have an interrelated history of developing standards for these devices. The IEC produced the first such standard “Testing and calibration of ultrasound therapeutic equipment”(1963). The FDA, with the IEC document as guide, developed its own “Ultrasonic Therapy and Surgery Products Performance Standard”(1978, 2012). Then the IEC, with FDA involvement and using many of the FDA’s concepts, produced “Medical electrical equipment—Part 2-5: Particular requirements for the basic safety and essential performance of ultrasonic physiotherapy equipment (1984, 2000, 2009) and “Ultrasonics—Physiotherapy systems—Field Specifications and methods of measurement in the frequency range 0.5 MHz to 5 MHz” (1996, 2007, 2013). FDA personnel are also currently leading an IEC effort to write a standard dealing with new, lower frequency physiotherapy. The FDA is also committed to harmonizing FDA regulations with IEC standards whenever possible. This presentation recounts the history of these efforts and examines some similarities and differences among the documents.
Ultrasound molecular imaging
Authors: Lindner Jonathan
Published: June 2017

Non-invasive in vivo molecular imaging technologies are uniquely poised to be able to temporally evaluate vascular adaptations to disease and the impact of new therapies. These technologies have been used to study vascular changes in various forms of cardiovascular and inflammatory disease and cancer. The approaches for studying the macro- or microvasculature with non-invasive imaging go beyond anatomic or perfusion characterization and instead yield information on vascular phenotype by either analyzing novel signal features or using targeted contrast agents that reveal the molecular underpinnings for disease. This talk will review new developments in ultrasound molecular imaging techniques that are likely to have a substantial impact on the understanding of pathophysiology, the development of new therapies, or diagnosis of disease in patients. Topics of focus will include recent advances in molecular imaging for the evaluation of: (1) atherosclerotic disease, (2) tissue inflammation or ischemic injury; and (3) thrombus or prothrombotic environment, (4) angiogenesis and stem cells. The discussion will also include a discussion of how these different approaches may play a role to solve current clinical deficiencies.
Effect of molecular weight on sonoporation-mediated uptake in human cardiac cells
Authors: Bhutto Danyal F. , Murphy Emily M. , Zhao John , Moore Joseph B. , Bolli Roberto , Kopechek Jonathan A.
Published: June 2017

Sonoporation of cells induced by ultrasound-driven microbubble cavitation has been utilized for intracellular delivery of molecular therapeutics. The molecular weight of therapeutic agents can vary significantly, with DNA plasmids often larger than 5 MDa, siRNAs and miRNAs ~10 kDa, and other drugs often less than 1 kDa. Some studies have suggested that sonoporation-mediated uptake may decrease at higher molecular weights due to slower diffusion rates, but experiments with equal molar concentrations have not been reported. Therefore, the objective of this study was to explore the effect of molecular weight on sonoporation-mediated uptake of fluorescein (0.33 kDa) or fluorescent dextrans (10 kDa, 2 MDa) using equal molar concentrations (100 nM). Sonoporation was induced in cultured human cardiac mesenchymal cells using lipid microbubbles and 2.5 MHz B-mode ultrasound (P4-1 transducer, Verasonics Vantage ultrasound system) and uptake by viable cells was measured with flow cytometry. No significant differences in sonoporation-mediated uptake were measured between molecules of different sizes at equal molar concentrations (ANOVA p = 0.92). However, significant differences in uptake were observed at different molar concentrations and acoustic pressures (ANOVA p = 0.02). In summary, these results suggest that the effect of molecular weight on sonoporation-mediated uptake is minimal compared to drug concentration or acoustic pressure.
Optimization of liposome delivery using low intensity ultrasound and microbubbles
Authors: Ruan Jia-Ling , Browning Richard J. , Yesna Yildiz , Vojnovic Borivoj , Stride Eleanor P. , Kiltie Anne
Published: June 2017

Liposomes are versatile drug delivery microvehicles to carry small molecule therapeutics and have a steadily growing global market share. Liposomal formulations can stabilize therapeutic compounds, promote cellular uptake, and improve biodistribution. The controlled delivery of liposomes can be further enhanced by ultrasound and microbubbles. Here we study the effect of ultrasound-mediated liposome delivery with microbubbles. By incorporating the fluorescent lipophilic dye, DiO, we investigated the effect of different liposome loading techniques and microbubble conjugation on liposome delivery in vitro. We found that active-loading liposomes demonstrated a better ultrasound-mediated delivery efficacy when conjugated with microbubbles than when used as a free drug. We also investigated the acoustic parameters: pressure (70 to 2000 kPa), duty cycle (10 to 50%), and PRF (2 to 1000 Hz); at a fixed 1 MHz center frequency for optimal liposome delivery with low cell detachment. Our results indicate that the liposome-carried microbubbles could be a promising new drug delivery vehicle to incorporate into the current chemoradiation therapy regime against cancer.
Towards using acoustic waves as a therapeutic tool for osteogenic differentiation
Authors: Shearer Lucas R. , Elefante Anna , Arabiyat Ahmad , Maynard Jacqueline , Kwaczala Andrea , King Eoin A.
Published: June 2017

Mesenchymal stem cells that reside in the bone marrow are unique in that they have the potential to differentiate into several cell types such as bone, fat, or cartilage. The mesenchymal stem cells are responsible for maintaining bone by differentiating into osteoblasts. Previous research has demonstrated the ability to influence this differentiation process through mechanical or chemical stimulation. Delivered at various frequencies and amplitudes, mechanical vibration is being considered as a non-drug treatment of osteoporosis. This paper reports on a study conducted in the University of Hartford to examine the possibility of using acoustic excitation, rather than mechanical vibration, to control cell differentiation. In vitro cell cultures (containing MC3T3-E1 pre-osteoblasts) were excited with white noise in a reverberation chamber for 30 minutes each day, over a four-day testing period. Preliminary results indicate an increase in cell proliferation due to acoustic excitation, but perhaps more significantly, prove that cells can be successfully transferred to and from a controlled acoustic environment. A more rigorous test regimen, including the development of a desktop stimulation chamber, has been scheduled to further quantify the response of these cells to similar acoustic stimulus.
Parameter variations for a porous layer simulation
Authors: Saati Khosroshahi Ferina , Moheit Lennart , Marburg Steffen
Published: June 2017

Porous media are widely known in the areas concerning noise absorption and interior and exterior acoustics. Among the numerical techniques to simulate a porous layer is finite element method using commercial software exist and actively update the range of models offered. In this work, an investigation is done using a no-flow basic problem. By variating material pore complexity and properties, different models are studied to enhance the understanding of the various treatments.
Miniature accelerometers for sensing middle ear motion
Authors: Hake Alison , Zhao Chuming , Grosh Karl
Published: June 2017

Acceleration sensors are prevalent in handheld electronics, navigation systems, and physical activity monitors as well as for vibration measurement. There are many measurement applications, such as sensing human middle ear motion, that require miniature, low-noise sensors to detect low-amplitude vibration. Both capacitive and piezoresistive MEMS accelerometers have been used for vibration sensing of the middle ear. Recent capacitive designs are large (base area of 2.5 mm x 6.2 mm) and have a limited bandwidth of 6.44 kHz. Low-noise piezoresistive devices power requirements are high for hearing instruments, greater than 1 mW. Commercial piezoelectric accelerometers are a viable means for vibration detection; while small, they are still large and lacking proper electronic connections for middle ear sensing applications. The aforementioned problems motivate the design of a small, passive, broadband accelerometer with low input referred noise (IRN). In this work, we design a micromachined, piezoelectric bimorph cantilever accelerometer for broadband, low-amplitude vibration sensing. An analytic model is developed to minimize the IRN. The analytic expression allows for rapid design of many system parameters that are verified through finite element analysis.
Feasibility study on a highly-directional parametric array loudspeaker applicable to mobile devices
Authors: Been Kyounghun , Ahn Hongmin , Kim Jin-Young , Kim In-Dong , Kim Joung Hoa , Lee Gibae , Bae Jinho , Lee Chong Hyun , Moon Wonkyu
Published: June 2017

A conventional parametric array (PA) loudspeaker has a relatively small aperture and produces a highly directional audible sound beam. Due to limitations arising from their size and power consumption, standard PA loudspeakers are not used in mobile devices. PA loudspeakers are typically larger than 25 cm and require more than 60 W. We show that piezoelectric micro-machined ultrasonic transducer (pMUT) arrays can emit highly directional ultrasonic sounds with a power efficiency of up to 80% [Je and Moon, Ultrasonics 53, 1124-1134 (2014)]. Highly directional sound beams with a frequency bandwidth of 13 kHz can be generated efficiently by pMUT arrays with two resonant frequencies [Je and Moon, JASA 173(4), 1732-1743 (2015)]. We used a signal processor, power amplifier, and pMUT array to build a loudspeaker system that is smaller than, and requires less power than, a conventional PA loudspeaker system. In our loudspeaker system, the maximum sound pressure level (SPL) is 75 dB, ± 3 dB frequency bandwidth is 12.5 kHz, and the total power consumption is 3.4 W. Hence, this loudspeaker system could potentially be used in mobile devices. [This work was supported by Samsung Research Funding Center, SRFC-IT1404-00.]
Collaboration, not oration: Tips for engaging students and promoting active learning in large classrooms
Authors: Kloepper Laura
Published: June 2017

Students state that traditional lectures are boring, and studies show that traditional lectures are ineffective and result in higher student failure rates than in active classroom settings. Unfortunately, large class sizes at many institutions prohibit some of the active learning strategies that are feasible in small classrooms. Moreover, increased time constraints of faculty members further limit one’s ability to assess individual learning in the classroom. Here, I demonstrate multiple techniques to incorporate into traditional lecture formats that increase student engagement, provide immediate assessment of lecture material, deepen critical thinking, and motivate student learning—all without increasing the time demands of the instructor.
Effective and efficient grading for assessing student learning
Authors: Ludwigsen Daniel
Published: June 2017

For decades, quality of assessment has increasingly become a part of the discussion of good teaching in higher education. New faculty (and older ones) may be overwhelmed at the thought of comprehensive assessment of student learning at the level of individual courses and entire degree programs, on top of keeping up with grading and feedback for each student. However, if student assignments are used effectively and efficiently to assess student learning, students perceive the process as fair, grades become more meaningful, and data is generated to inform evidenced-based improvement of instruction. While some graduate programs and early-career mentoring include course design, learning objectives, and assessment of student learning, not all Ph. D. programs require training in even basic elements. New faculty may benefit from an introduction to a “backwards” approach to course design, a survey of learning assessment tools, and current best practices in grading. Examples from acoustics courses at Kettering University illustrate these ideas, with lessons learned from recent ABET accreditation in engineering and applied physics programs.
Incorporating local experts into a Physics of Music class
Authors: Dostal Jack
Published: June 2017

The Physics of Music is a general education science class open to all students at Wake Forest University. A broad range of topics are covered: wave physics, hearing and the ear, the voice and singing, musical instrument function and performance (winds, strings, and percussion), room acoustics, and more. An instructor for such a course is not usually a master of all these areas. In this talk, I will describe how we engage some of our local experts (singers, instrumentalists, piano tuners, doctors) to enhance the student experience of learning about physics and music. Activities to incorporate their specialties into the class will also be described.
Effective abatement of railway noise in Germany
Authors: Weinandy Rene
Published: June 2017

Many people are exposed to high levels of noise that adversely affect their health and quality of life. Noise is now experienced virtually every-where and around the clock. Therefore, noise is an important environmental issue in Germany and within the EU. Under the Directives on rail traffic across Europe, the EU Commission has established pan-European noise thresholds for new types of rolling stock in the Technical Specifications for Interoperability (TSI). The most important consequence of the noise thresholds is that particularly noisy rolling stock fitted with cast iron block brakes is no longer permitted. The challenge is now to replace these brakes in especially noisy freight wagons in the current rolling stock with quieter braking systems. As a financial incentive for rail operators to refit such rolling stock with quieter brakes, track access charges are implemented in Germany. Additionally, there are a number of technical and legal measures available. The presentation will give an overview on these measures to efficiently abate railway noise in Germany.
Suggestions for a future ANSI sleep disturbance standard
Authors: Luz George A.
Published: June 2017

Recently, the American National Standards Institute (ANSI) withdrew the standard for sleep disturbance from transportation noise which it had published in 2008. This standard failed because the original working group had adopted a (Skinnerian) “black box” approach to describe the behavior of two intertwined neural systems: (1) an energy-dependent defense response and (2) an information-based threat analysis network. This paper reviews what brain scientists have discovered about the information-based network in the years between the publication of the standard and its withdrawal and argues that it is essential for a future standard to address the role of slow wave sleep. This assertion is followed by a discussion of the pros and cons for adapting current models of noise-induced disturbance of slow wave sleep (Basner, McGuire, Davies and others) into a future standard. Recommendations for a future standard include: (1) break with the logic of the National Environmental Policy Act of 1969, (2) focus on protecting the most vulnerable, (3) address all types of anthropogenic sound, (4) provide for cost cutting through emerging technology, and (5) include procedures for mitigation.