bluuebunny/crossref_metadata_2025 huggingface dataset:
Noise maps for complex geography over mountains.
Authors: Chuqillanqui Fidel , Gushiquen Elena , Montano Walter
Published: October 2010

International Credit Organizations are more strict concerning the demand that a prediction of the impact will be made, which would originate the installation of industrial plants. Software programs are powerful tools as long as the input data are convincing, for which it is important to have sufficient information of the existing sound pressure level in the area of construction, like of the loud emissions of the electromechanical equipment being used, which normally are not available or the factory data are based on bench tests or results that can apply to the models recognized by physical-mathematicians. Prediction studies by software, of the industrial plant to settle to 3500 msnm impact, and sound level measurements were made using the measurements’ uncertainty criteria under ISO 1996-2: 2007 recommendations, as well as the adaptation of the ISO series 374X, to know the sound power levels of electromechanical facilities being used in the project.
Considerations for near-field acoustical inverse measurements on partially correlated sources.
Authors: Wall Alan T. , Gee Kent L. , Neilsen Tracianne B. , James Michael M.
Published: October 2010

Array-based acoustical inverse methods are being explored for the localization of noise sources in the jet plume of high-power military aircraft. For any partially spatially correlated source, the appropriate localization technique depends largely on the source correlation properties and the proximity of the measurement array to the source. Since correlation characteristics in high-power jets are difficult to measure, the coherence lengths measured in the near field are explored to guide the selection of the appropriate technique. Near-field coherence length and wavenumber decomposition results are presented for numerically simulated, partially spatially correlated sources to benchmark the technique. The coherence lengths of data measured near a high-power military jet aircraft are shown and the implications for the feasibility of various acoustical inverse methods for source localization are presented. [Work supported by Air Force Research Laboratory SBIR.]
Relating patient physiology to the hospital sound environment.
Authors: Hsu Timothy Y. , Ryherd Erica E. , Ackerman Jeremy , Persson Waye Kerstin
Published: October 2010

Sounds in hospital wards have previously been linked to physiologic changes in patients including sleep disturbance, variation in vital signs, and impaired pain management. However, relationships between sound measurements and variations in physiologic measures remain somewhat unclear. This presentation will discuss a pilot study that focuses on the relationships between acoustic measurements and patient physiology in a Swedish medical-surgical intensive care unit. Sound measurements as well as physiologic measures including heart rate, oxygen saturation, respiratory rate, and blood pressure were recorded simultaneously for 24-h periods in 18 patients. Several different analyzes were performed to assess the relationships between the acoustic results and the patients’ physiological measurements. The data demonstrated a statistically significant relationship between the recorded physiological responses and acoustic measurements. The results build upon previous results to further elucidate the relationships between hospital acoustics and patient physiological arousal. This paper is part of a series of studies that evaluates the hospital soundscape and the response of patients and staff members. [Work supported by ASA and Swedish FAS.]
On some recent applications of the Coanda effect to acoustics.
Authors: Lubert Caroline P.
Published: October 2010

Over the last half century or so, the Coanda effect (which causes a jet of fluid to follow a curved surface) has been increasingly widely observed in a variety of applications including medicine, industry, maritime, and the natural world. Devices employing this effect usually offer substantial flow deflection and enhanced turbulence levels and entrainment compared with conventional jet flows. However, these prospective advantages are generally accompanied by other significant disadvantages such as flow detachment and a considerable increase in associated noise levels. This paper details some of these applications and discusses why the increased noise levels associated with this principle meant that its full potential is yet to be realized, and how these can be mitigated.
Multichannel active control of tonal fan noise in laptops.
Authors: Cordourier-Maruri Hector , Orduña-Bustamante Felipe
Published: October 2010

A multichannel active noise control system, based on a feed forward LMS algorithm, is simulated and implemented experimentally to reduce tonal noise components from internal cooling fans in laptops. Several 3-D simulations were carried out in order to determine the proper number and location of sensors and actuators, with three different criteria of reduction: sound pressure, sound intensity at discrete points, and global sound power. Results of simulations show reductions of up to 38 dB in the radiated sound power for a configuration consisting of three control actuators, three error sensors, and one reference sensor. Subsequently, experimental tests were undertaken of active noise control in a laptop, with the proposed configuration, in an anechoic chamber. Results show reductions of up to 15 dB in the sound pressure levels of individual error sensors. Hence, it is concluded, both theoretically and experimentally, that active noise control is a promising strategy to reduce tonal fan noise in personal computers.
Delay detectability and speech rate as a function of delay duration in auditory feedback.
Authors: Bhattacharyya Sudipa , Armson Joy , Kiefte Michael
Published: October 2010

The relationship between delayed auditory feedback and speech rate, speech error rate, and delay detectability was examined as a function of delay duration. Thirty adult participants read paragraphs while listening to delayed feedback at 10 logarithmically spaced delay durations between 0 and 180 ms. Significant main effects of delay duration was found for speech rate as well as number of disfluencies. In addition, there was a significant effect of delay duration on the detectability of the delay as well as on reaction times even for very short delays (i.e., 16 ms). For reasons that are currently unknown, delays at 45 ms were significantly more difficult to detect than delays of either 32 or 64 ms. This was evident for both reaction-time data as well as signal-detection data. There was a linear, downward trend in speech rate for delays of 32 ms and longer, with a small deviation at 45 ms. Disfluencies were infrequent but there were significant increases in stuttering-like disruptions at longer delays (i.e., 128–180 ms). [Work supported by SSHRC.]
Examination of coarticulation features in Mandarin tone productions using locus equation.
Authors: Chen Yang , Ng Manwa L.
Published: October 2010

Locus equation (LE) was designed to examine the spectral changes during coarticulated consonant-vowel (CV) utterances through obtaining a regression straight-line which fits to points on a 2-D Cartesian coordinate system, with the ordinate and abscissa corresponding to onset F2 and target (mid-vowel) F2, respectively [Lindblom (1963); Sussman et al. (1992)]. The linear LE functions, according to Sussman et al. (1991), were referred as potential “CV prototypes”, of which the slopes are considered to indicate the extent of coarticulation-induced variation in a CV(C) context. This study attempts to investigate coarticulation features in Mandarin speech sounds by comparing LE among different Mandarin tones. A tonal language, specifically Mandarin, where a change in tone of a syllable leads to a change in lexical meaning, will be used in the study. There are four contrastive tones in the Mandarin, each of which is realized by vocal pitch variation in vowel segment. Based on recent findings of kinetic interrelations between phonatory and articulatory systems during Mandarin tone productions [Gao and Esling (2003)], this study intends to determine if coarticulation features in Mandarin CV contexts vary with variation of lexical tones at which each of the following vowel sounds is produced.
The articulatory kinematics of stopping speech.
Authors: Tilsen Sam
Published: October 2010

For over 35 years, the stop-signal paradigm [cf. Ladefoged et al., J. Acoust. Soc. Am. 54, 1105–1108 (1973)] has been neglected in speech research. An experiment was conducted in which speakers were given a stop-signal either just prior to or during the production of monosyllabic and disyllabic nonword sequences, which contrasted in stress pattern and place of onset consonant articulation. Acoustic and articulatory kinematic data were collected with the aim of determining how speakers halt speech mid-utterance. It was hypothesized that upcoming syllable stress may influence how quickly speech can be terminated. Three findings of interest will be presented: (1) speakers halt speech more slowly when signaled to do so prior to a stressed syllable than an unstressed syllable; (2) to halt airflow, many speakers use an upcoming onset consonant gesture in the target utterance, in addition to a glottal stop; (3) a number of changes occur in the relative timing of laryngeal and supralaryngeal gestures prior to stoppage of speech. A dynamical model will be presented of amplitude-coupled stress, syllable, and articulatory planning systems, which can simulate the effects of syllable stress on stop-signal RT and observed changes in the relative timing of articulatory gestures.
Using digital ultrasound to investigate trill vibration.
Authors: Whalen D. H. , Iskarous Khalil , Grathwohl Will , Proctor Michael
Published: October 2010

Apical trills last about 150 ms, with individual closure and opening parts between 10 and 30 ms. [Ladefoged et al., J. Int. Phonetic Assoc. 7, 46–54 (1977).] A digital ultrasound study revealed articulatory details correlated with spectral output. The Haskins Digital Ultrasound System allowed imaging at 127 Hz of apical trills in Russian and Spanish. [M. Proctor, Ph.D. dissertation, Yale University (2009).] Trills were produced in a VCV environment by two Spanish and two Russian speakers. Apical vibration was measured by tracking the intersection between the tongue edge and a polar gridline extending from the center of the ultrasound transducer to the tongue blade, (since the tongue tip cannot be resolved). rms amplitude was measured for three frequency bands (200–1000, 1000–2000, 3000–4000 Hz). Correlations were found between amplitude and tongue height even though measurement was in the blade region. Even when the tongue tip does not contact the alveolar ridge, the amplitude is affected. Further, the higher the tongue, the higher the frequency band that showed a change in energy. It is shown that the results are explainable on aeroacoustic grounds.
Pattern classification analyzes of vowel-inherent spectral change in adults and children.
Authors: Assmann Peter F. , Nearey Terrance M.
Published: October 2010

This study compares the pattern of time-varying spectral change in a database of vowels spoken in hVd words by adults and children ranging from 5 to 18 years. Measurements of vowel formant frequencies (F1, F2, and F3), mean fundamental frequency, and duration were used to train a pattern classifier to determine the optimum sampling locations for the purpose of vowel classification. A series of linear discriminant analyzes was carried out, using leave-one-out cross validation to classify the test stimuli. These analyzes differed in the temporal location(s) at which the formant frequencies were measured and the number (1, 2, or 3) of sample points. For all age and sex classes, classification accuracy was higher when two samples were used rather than a single frame, with a mean increase in accuracy of 10.8%. Adding a third sample point produced marginal improvement in classification, with less than 1% change overall. The highest classification results were obtained when the initial sample was taken relatively early in the vowel (around the 20% point), while the second sample was taken around the 70% point, with relatively minor variations in classification scores across age and sex categories.
Investigation of the inter-articulator correlation in acoustic-to-articulatory inversion using generalized smoothness criterion.
Authors: Ghosh Prasanta , Narayanan Shrikanth
Published: October 2010

The movements of the different speech articulators are known to be correlated to various degrees. Thus, it is important to investigate whether the estimated articulator trajectories in the acoustic-to-articulatory inversion preserve similar correlation patterns. In this work, the inter-articulator correlation in the context of the articulatory inversion is investigated using the generalized smoothness criterion (GSC). In GSC, the articulator-specific smoothness constraints are considered during articulatory inversion. GSC estimates each articulator separately without explicitly using any correlation information between the articulators and, therefore, a methodology is proposed to explicitly impose the inter-articulator correlation for the acoustic-to-articulatory inversion using GSC. Based on the theoretical and experimental investigations, it is found that the GSC inherently preserves the inter-articulator correlation to a certain extent and, hence, there is no significant benefit by explicitly using the inter-articulator correlation information during the articulatory inversion using GSC.
A comparison of algorithms to automatically extract vowel formants and nasal poles from tagged vowels in PRAAT.
Authors: Cristià Alejandrina
Published: October 2010

The goal of the present research was to develop an easy-to-use PRAAT script yielding robust measurements of acoustic correlates of vowel quality and vowel nasality. Several algorithms were scripted in PRAAT and evaluated on two corpora. The first was the Hillenbrand corpus, containing /hVd/ words in isolation, spoken by 50 men, 50 women, 29 boys, and 21 girls, where vowels have been hand-tagged by experts. The best performing algorithm yielded extremely high correlations with the expert-measured F1 and F2 frequencies (r>0.95). The second corpus consisted of spontaneous speech by American English and Canadian French women, addressing either their infant or an adult, and where several types of vowels had been hand-tagged (including point vowels /i,a,u/, frequently used to assess vowel space size; and contrasts of vowel tenseness, likely involving F1 and F2 frequencies; and vowel nasality, correlated with F1 bandwidth, as well as its amplitude in relation to the nasal poles P0 and P1). Although, even the best algorithm yielded spurious F2 values for infant-directed /u/'s, measures were robust indicators of vowel quality and nasality in non-back vowels across the different speakers, languages, and registers. Thus, this script may be useful, particularly for non-specialists, since it only requires vowel-tagging.
Scattering from elastic objects in a waveguide using the finite element technique.
Authors: Abawi Ahmad T.
Published: October 2010

Computation of scattering from an object in a waveguide requires the solution of the wave equation by simultaneously satisfying boundary conditions on the surface of the object as well as the boundaries of the waveguide. An accurate solution requires that the computational domain be discretized at least at one-tenth of the acoustic wavelength. For a computational domain tens or hundreds of wavelength large, this results in very large systems of linear equations whose solution is a daunting numerical task. To cope with the numerical complexity, in this paper we solve this problem by using a combination of the finite element and the spectral integral techniques. The finite element technique is used to compute the scattered field and the spectral integral technique is used to compute the waveguide Green’s function. The scattered field and the waveguide Green’s functions are used in the Helmholtz–Kirchhoff integral to compute the field everywhere in the waveguide. The accuracy of the technique is tested by comparing its results with those from a full finite element solution in 2-D. The technique is then extended to 3-D.
Sound penetration into unconsolidated sand: Quantifying and predicting acoustic scattering from proud, half buried and fully buried targets in both the laboratory and littoral environments using direct measurements of sound speed in the sandy bottom.
Authors: Simpson Harry J. , Houston Brian H. , Waters Zachary J. , Berdoz Alain R. , Amon Danial L. , Frank Philip A. , Liskey Steve W. , Kraus Larry A. , Bucaro Joseph A.
Published: October 2010

The impact of unconsolidated sandy bottoms on sound propagations and scattering from targets of interest is quantified with a series of experiments in both the laboratory and in littoral environments. In the laboratory, the sound speed and attenuation is well quantified and a series of proud, partially buried and fully buried scattering measurements from a variety of targets is discussed. The compressional sound speed and dispersion is important in understanding the propagation of sound into and out of sandy bottoms and the impact of scattering from buried targets both above and below the critical angle. The compressional sound speed and dispersion are important to understand and model the unconsolidated sandy bottom and to predict the impedance loading and impact to scattering signatures from targets. We will detail several laboratory and field measurements of the compressional sound speed and scattering from buried targets. Also, we will show measurements and predictions of scattering from targets in various states of burial. Propagation models will be used to predict sound propagation and scattering in the sandy bottom and will be compared to measurements of sound propagating through the sandy bottom at close and long ranges. [Work supported by ONR.]
Sediment sound speed and attenuation results from the sediment acoustics experiments in 1999 (SAX99) and 2004 (SAX04).
Authors: Thorsos Eric I. , Williams Kevin L. , Hefner Brian T. , Jackson Darrell R.
Published: October 2010

Sediment acoustics experiments in 1999 (SAX99) and 2004 (SAX04) were conducted in shallow water off the Florida Panhandle near Fort Walton Beach, Florida. Measurements were made of the frequency dependence of sound speed and attenuation in sandy sediments, supplemented by detailed environmental characterization. Following SAX99 laboratory measurements were conducted to further investigate the physical mechanisms contributing to the frequency dependences observed. An overview will be given of these sound speed and attenuation results, and the implications for sediment acoustics modeling will be discussed. [Work supported by ONR.]
Sound control in mass transit stations: With case study from Central Anatolia.
Authors: Bal Kocyigit Filiz , Kocyigit Ahmet
Published: October 2010

The aim of this research is to evaluate sound control in mass transit stations, with a case study from Central Anatolia. For this aim Ankara’s central metro station is selected. Today, with the improvement of building technology, integration of different professions is increased. With this integration, special systems are used for some of the buildings, named “special buildings.” At these buildings, which have special character, sound is one of the professions and it needs acoustic criteria for their special characters. Nowadays authorities understand that one-value of dB is not enough for accepting noise criteria, and researched the value depending on frequency band and noise criteria curves. However, one should understand that these works are not enough for the architecture, up to now. Especially for the “intelligent buildings”, which is one specific part of “special buildings”, for the purpose of verifying the noise criteria, which depend on frequencies, analyzing the frequency bands of noise is very important. In the work, Kizilay station was selected, for example, as an intelligent building and the frequency of noise was analyzed and noise criteria for the interior were proposed. The comparison of criteria and tests results showed that, between 250 and 2000 Hz frequency at Saturday and Monday, there are big problems.
Acoustical drawbacks at one type project for education buildings.
Authors: Bal Kocyigit Filiz
Published: October 2010

The aim of this research is to evaluate acoustical quality drawbacks at one type projects for education buildings. For this aim Ankara (for Central Anatolia) and Karabuk (for Black Sea region) regions’ national primary schools are researched according to room acoustics condition and environmental factor. These schools’ projects are compared with some private schools and other cities’ national school projects, and several sounds levels are measured at different critical zones in schools. Researches showed that there are several effected sound sources in schools which sometimes can be incessant, sometimes temporal, and directly affect the indoor noise level. The importance of these levels is, first, at the signal to noise ratio for communication between students, teachers, and other staff. Second, hearing and understanding the loudspeaker in daily period and especially during emergency time is vitally important. At this research, two different critical materials, conditions, and areas are determined; daily and constantly critical zones and critical zones at emergency conditions such as stairs, emergency doors, corridors, elevator indoor, etc. Not only emergency time but also daily period problems which are directly related to the noise level in schools need different solutions for the control of acceptable sound levels according to international standards.
Corpus aspects to measure Spanish speech intelligibility: The methodology.
Authors: Sommerhoff Jorge , Rosas Claudia
Published: October 2010

This study presents the methodology employed to develop a subjective measurement tool for Spanish speech intelligibility. It is an experimental corpus, consisting of logatoms with a consonant + vowel + consonant structure, including all phonetically possible combinations in Spanish, with data from the first stage of the ongoing research project Fondecyt Regular No. 1090249 (CONICYT) in order to draw up lists of logatoms to measure the articulation percentage and their correlation with the speech transmission index. The information provided will facilitate the local improvement of the acoustic quality when building public educational facilities and will also contribute to the national development of efficient habitability standards through a novel Spanish linguistic test aiming to serve as a reference for its application in the rest of the world’s Hispanic varieties.
Indoor environmental quality and acoustical data.
Authors: Costello Amy , Roy Kenneth
Published: October 2010

Building indoor environmental quality (IEQ) surveys such as that developed by the Center for the Built Environment (CBE) at the University of California at Berkeley are currently collecting data from many buildings around the country and the world. Other entities with a vested interest in the operation of the United States building stock are also collecting acoustical data. While these data sets are publically available, they have not been analyzed by the acoustical community. As the concept of sustainability grows, the importance of “proving” that IEQ in buildings including acoustics performs as designed will also grows. This paper will review some of the available acoustical survey data sets including the Environmental Protection Agency’s Building Assessment Survey and Evaluation Survey (BASE) and National Center for Education Statistics’ Public School Principals Report.
Prospects of the treatment of acoustical insulation in building codes of México.
Authors: Vergara Mario E.
Published: October 2010

The acoustical insulation of dwellings in order to protect them from environmental noise is an issue not yet addressed in building regulations in Mexico, but the Federal Government, through the National Housing Commission (CONAVI), has promoted the development of a Building Code for Dwellings, which in the future could include provisions about this subject. So far, authorities have focused their attention on the problems of energy efficiency and thermal insulation of public buildings. On the subject of housing, they have proposed levels of thermal insulation that could be adopted as standards and have also promoted the study of constructive solutions appropriate to those standards. The levels of acoustical and thermal insulation that are produced by various constructive solutions used by housing developers in the metropolitan area of the city of Puebla, Mexico, are analyzed in this work in order to compare their performance with international standards. A more comprehensive regulatory framework is needed in Mexico, and the results of this research will produce recommendations on acoustical insulation capacities that the National Housing Commission could include in its code. [Project supported by funds from CONACYT and CONAVI.]
Correlation between reverberation time of restaurants in the city of Monterrey, Mexico, and the opinion of its clients on their acoustical comfort.
Authors: García Mederez Adrián , Lara Ochoa Carlos Armando , Cpich Guerrero Jorge Alejandro , Tapia González Pablo Ernesto , Elizondo Garza Fernando J.
Published: October 2010

The acoustical comfort in restaurants can be perceived by the clients in terms of interpersonal communication, tranquility to eat, and also as environmental happiness at the place. That is a subjective factor that can make more popular a certain restaurant and can affect its business success. The reverberation time is a parameter related to the physical characteristics of a room and has influence on the acoustical sensation perceived by the costumers at a restaurant. In this paper the results of measurements of the reverberation time in restaurants at the city of Monterrey, Mexico, are compared with the opinion of its clients on the perception of their acoustical comfort.
Software tools for marine mammals acoustic surveys and the implementation of mitigation procedures.
Authors: Pavan Gianni , Fossati Claudio , Caltavuturo Giovanni , Francia Cristina , Bassanini Manuel , Modena Nicola
Published: October 2010

Several research groups are by now developing and working with software and hardware to implement PAM services worldwide. Despite considering standardization as a fundamental requirement, extensive experimentation still has to be done. In particular, the balance between software based and operator based classification, analysis, and interpretation is critical. A software suite has been developed and is continuously updated to assist researchers in conducting acoustic monitoring in marine mammals surveys; the aim is to keep improving the detection and classification of cetacean sounds, the source localization, and the real-time integration with visual detections into a GIS. The ultimate goal is to produce data for distribution and density estimation, and to provide a solid platform for mitigation. These tools have been developed throughout 10 years of SIRENA research cruises (NATO URC) and LDEO (Columbia Univ., NY) seismic cruises. The core of the system is the SEAPRO PAM software package that provides multisensor/multichannel wideband recording and spectrographic display along with navigation data management and display, operator based sound classification, GIS plotting (integrated with sightings), and audio tools to make all received signals audible to the operator. Other modules provide spectro-statistical noise analysis, AIS data visualization, sound classification, and network transmission of acoustic data for distributed processing.
TRITON software package: Analyzing large passive acoustic monitoring data sets using MATLAB.
Authors: Wiggins Sean M. , Roch Marie A. , Hildebrand John A.
Published: October 2010

As consumer electronic technology continues to advance with lower power, higher speed, larger data capacity, and lower costs, the ability to collect large acoustic data sets becomes more practical. However, working with these large data sets can be challenging and requires different approaches to managing and analyzing the data than traditionally have been used with small data sets. TRITON is a software package developed for working with long-term, wide-band, multi-terabyte, acoustic data sets. One of TRITON’s primary functions is to make long-term spectrograms from a large group of small (1 Gbyte) sequential data files. These long-term spectral averages provide a means of quickly evaluating long durations (hours) of wide-band data for sounds such as animal calling bouts and permit the user to zoom in to traditional spectral/time domain displays for finer scale analysis. TRITON has a graphical user interface and is based in MATLAB, which allows for easy modifications for specific data processing and analysis requirements. Examples of this are whistle and echolocation click detectors developed as TRITON extensions.
Rapid acquisition of marine mammal evoked potential audiograms by stranding networks.
Authors: Houser Dorian S. , Moore Kathleen , Sharp Sarah , Finneran James J.
Published: October 2010

Two portable evoked potential measurement systems were constructed for use by stranding networks to determine the feasibility of non-expert collections of cetacean audiometric data. The systems were based on a customized version of the evoked response study tool with a simplified user interface designed for testing odontocetes. Stranding network personnel were provided one day of training on the system. Between January and April, 2010 the International Fund for Animal Welfare Marine Mammal Rescue and Research program attempted unsupervised AEP measurements on five live-stranded odontocetes: a harbor porpoise (Phocoena phocoena, n=1), common dolphins (Delphinus delphis; n=3), and an Atlantic white-sided dolphin (Lagenorhyncus acutus, n=1). Full or partial audiograms were obtained from the common and white-sided dolphins. The skin condition of the harbor porpoise was sufficiently poor as to prevent consistent electrode contact during testing. No audiogram was obtained from this animal. Audiograms were typically dolphin in nature with an upper frequency limit approaching 160 kHz. Stranding network success at collecting odontocete AEP audiograms demonstrates that hearing tests can be conducted by non-expert operators with a streamlined and simplified testing system. This approach will increase the rate at which audiometric data are collected from marine mammals.
Ocean bottom profiling with ambient noise: A model for the passive fathometer.
Authors: Traer James , Gerstoft Peter , Siderius Martin
Published: October 2010

An analytical model is presented for the passive fathometer response to ocean surface noise, interfering discrete noise sources, and locally uncorrelated noise in an ideal waveguide. The leading order term from the ocean surface noise produces the cross-correlation of vertical multipaths, yielding the depth of sub-bottom reflectors. Discrete noise incident on the array produces peaks that may obscure the sub-bottom reflections but can be attenuated with the use of adaptive processing. Such adaptive methods are described and applied to several data sets to demonstrate improvements possible as compared to conventional processing. Motion of the array, due to surface waves, is inferred from the passive fathometer response and, applying a correction for this motion, the seabed reflection is averaged coherently to yield an estimate of the seabed Green’s function.
Passive seabed remote sensing using ambient noise: Comparisons with active techniques.
Authors: Siderius Martin , Holland Charles W.
Published: October 2010

Remote sensing in the ocean using ambient noise techniques is starting to be considered a viable option for surveying seabed properties. Historically, active techniques have been used to measure seabed layering and reflectivity. Part of the appeal of ambient noise remote sensing is that it allows for surveying in areas where active sound transmissions are not allowed (e.g., in marine protected areas). Although it may seem far-fetched to expect passive noise remote sensing methods to extract similar information about the seabed as active methods, in recent years results have been promising. However, direct comparisons between active and passive methods have been limited. One of the best ways to measure seabed properties is using what is often referred to as wide-angle reflection measurements. One version of the technique uses a single hydrophone at a fixed location with a sound projector transmitting from close range out to about a kilometer. The analysis of the reflection measurements are very similar to the ambient noise technique in that the seabed layering is extracted from the time-domain data and the frequency domain reflectivity is used to determine seabed properties. In this presentation, we will compare results from active reflectivity measurements with ambient noise remote sensing.
A flexible implantable sensor for post-operative monitoring of blood flow.
Authors: Cannata Jonathan M. , Vilkomerson David , Chilipka Tom , Yang Hao-Chung , Han Sukgu , Rowe Vincent L. , Weaver Fred A.
Published: October 2010

A blood flow measurement system utilizing flexible ultrasonic Doppler patch-sensors and battery operated electronics was developed. These sensors can be wrapped around a blood vessel to safely and accurately measure flow. Prototype sensors were fabricated by spin-coating 12-μm-thick P(VDF-TrFE) films onto 25-μm-thick flexible polyimide substrates with patterned gold electrodes. The transmitting electrodes consisted of an array of equally spaced traces. Oppositely oriented electric fields were applied to alternate traces during polarizing so that when the traces are excited by a 40-MHz sinusoidal signal, the P(VDF-TrFE) film produces successive positive and negative pressure waves that sum to form two diffraction-grating beams at 39 deg with respect to blood flow. A uniform electrode for a receiving transducer was positioned to maximize the reception of the backscattered Doppler signal from the center of a 3-mm-diameter blood vessel. Patch-sensors were placed around the abdominal aorta of a New Zealand white rabbit. The mean peak blood velocity measured by the sensor during a 5-h period was 122 cm/s, which compared favorably to the peak velocity of 120 cm/s detected by a Duplex ultrasound system. [Work funded by NIH/NHLBI Grant no. R41-HL87467-01A2.]
A semi-quantitative method in microbubble-based ultrasound contrast imaging.
Authors: Kamiyama Naohisa , Yoshiara Hiroki , Yoshida Tetsuya
Published: October 2010

The aim of our study is to construct a semi-quantitative tool which can simply represent the measurable blood flow with a microbubble-based contrast agent. The possibilities of quantifying the blood flow are explored by many researchers to classify the tumors or to evaluate the response to anti-angiogenic therapy. Flash-replenishment (FR) sequence, which utilizes destruction of the bubbles by ultrasound exposure and observes reperfusion into the scan volume, has become a more applicable technique in contrast echography. The theoretical equations in FR sequence have been described to quantify hepatic parenchymal blood flow. The arrival time 2-D mapping was developed to acquire such diagnostic information easily in the routine examinations. This method watches the inflow of the microbubble in the scan image and paints colors pixel-by-pixel corresponding to the time of arrival. Results of the efficiency of this method will be shown, not only for tumor characterization but also for quantifying the fibrosis stage for diffuse liver disease.
Investigating vascular-targeting strategies with three-dimensional power Doppler ultrasound.
Authors: El Kaffas Ahmed , Giles Anoja , Czarnota Gregory J.
Published: October 2010

Vascular targeting agents have been recently combined strategically with existing cancer therapies to potentially enhance tumor response. Our aim was thus to investigate the role of blood vessels in radiation response and how blood vessels can be targeted to enhance treatments. Breast cancer MDA-MB-231 xenografts were treated with single radiation doses of 0–16 Gy alone, or in combination with Sutent, an antiangiogenic agent. 3-D ultrasound tumor data were acquired before and 24 h after treatment using a 25-MHz transducer and a VEVO770. The vascularity index (VI) was used to quantify blood from power Doppler data, while quantitative ultrasound spectroscopy (QUS) was used to monitor tumor cell death. Staining using TUNEL and CD31 of tumor sections was used to measure cell death and tumor vasculature distributions. Preliminary results indicated a VI decrease of up to 50% when tumors were irradiated with 16 Gy. Sutent-radiation combination treatments showed an increase in the VI, which may be associated with a vascular normalization effect. Analyses with QUS and TUNEL staining indicate an enhanced dose-dependent increase in tumor cell death when radiation was combined with Sutent. These results indicate that Sutent treatment may radiosensitize tumors by altering the tumor microenvironment. [Work funded by the Canadian Breast Cancer Foundation.]
High-frequency ultrasound Doppler velocimetry measurements of intra-cochlear structures in human temporal bones.
Authors: Brown Jeremy , Torbatian Zahra , Garland Phil , Adamson Rob , Van Wijhe Rene , Savage Julian , Bance Manohar
Published: October 2010

Hearing loss is one of the most prevalent, chronic, and fast growing disorders, affecting approximately one-tenth of the population. Diagnostic imaging tools currently used in this field such as CT and MRI do not have sufficient spatial/temporal resolution to properly diagnose most of the underlying causes of hearing loss. In this work, we present the first high-resolution velocimetry measurements of intra-cochlear structures using high-frequency (40 MHz) pulsed-wave Doppler ultrasound. A 40-MHz single-element transducer based on PMN-PT single-crystal piezoelectric was fabricated in-house and mounted onto the tip of a needle. The transducer was a side-looking circular disk with a 1 mm outer diameter. A custom data acquisition system was developed in order to perform pulsed-wave Doppler and was synchronized with an acoustic stimulus. Velocimetry measurements were performed on the basilar membrane located inside the cochlea of fresh temporal bones by imaging across the round window membrane and stimulating the eardrum with pure-tone sounds. For the first time, the vibration of the basilar membrane was measured on a completely intact cochlea using ultrasound velocimetry. The middle ear resonance could be detected by measuring the frequency-dependent basilar membrane velocities between 100 and 2500 Hz. This resonance was verified using a laser vibrometer.
Acoustics at Brigham Young University through the years.
Authors: Sommerfeldt Scott D. , Gee Kent L.
Published: October 2010

Brigham Young University (BYU) has a long and rich tradition in acoustics education and research. This legacy began in 1911 when Harvey Fletcher joined the faculty at BYU and mentored both Carl Eyring and Vern Knudsen. It continued with Eyring joining the faculty in 1924, Fletcher returning to BYU in 1952, and Bill Strong joining the faculty after that. The acoustics program at BYU has been significantly revitalized over the past 15 years, both in terms of the number of faculty and students involved with acoustics and with the expansion of the program to become interdisciplinary. This paper overviews the historical growth of the BYU acoustics program and highlights recent progress in student participation as well as the expansion of the facilities and research conducted at BYU.
Undergraduate and graduate acoustics education at Brigham Young University.
Authors: Gee Kent L. , Sommerfeldt Scott D.
Published: October 2010

The current acoustics program at Brigham Young University reflects efforts intended to better prepare students for jobs in industry, research, and academia. In the classroom, ongoing modifications to graduate-level coursework are intended to provide students with a solid foundation in core acoustics principles and practices. A new advanced undergraduate course has been developed to provide students with formal training in acoustics prior to the graduate level and prepare them for research, internships, and entry-level acoustics positions. In the laboratory, graduate students not only carry out research of significance, but often serve as peer mentors to undergraduate students new to the group. This permits undergraduate students greater opportunity to participate meaningfully in research activities and has resulted in an increase in undergraduate-authored presentations and publications.
History and educative programs of the Acoustics Laboratory of the Nuevo Leon State University in Monterrey, Mexico.
Authors: Elizondo-Garza Fernando J. , García Mederez Adrián , Lara Ochoa Carlos Armando
Published: October 2010

The Acoustics Laboratory of the Mechanical and Electrical Engineering School of the Nuevo Leon State University in Monterrey, Mexico, founded by Eng. Miguel Medina, has been the axis of the education, research, and consulting to companies and government in this field of science in the northeast of Mexico. In this paper the history of this department, its vision, the services offered, and the approach of the courses on acoustics that are offered to the students of the university as well as through continuing education and by other courses are presented.
Acoustics in the engineering degree studies in Uruguay.
Authors: González Alice Elizabeth , Rezzano Nicolás , Bonilla Pablo
Published: October 2010

The acoustics area has a very secondary place in the engineering degree studies in Uruguay. Only one early course on the physics of waves provides some idea of the broader aspects. Furthermore, some courses that used to provide the students a partial idea on some aspects of noise are no longer issued. Nowadays, most of the working market does not require high training on acoustics, but gradually noise issues are gaining importance and they are often addressed by professionals with no training in the subject. This fact has created in the collective imagination the idea that noise issues should be managed from an intuitive and empirical sense, rather than from a rigorous and formal approach, as would be desirable. Recently, environmental awareness has led people to include some basic aspects of environmental noise in the training of future civil engineers. Students who choose Civil Engineering on Hydraulics and Environmental will achieve further knowledge in their formation on environmental noise, its consequences, and management. On the other hand, the awakening of a “culture of the lawsuit” has generated the need of postgraduate activities to update and improve the skills of professionals interested in getting involved in this field.
Acoustics at the Georgia Institute of Technology.
Authors: Ryherd Erica E. , Hastings Mardi , Doane John
Published: October 2010

Acoustics at Georgia Tech spans multiple schools, including Mechanical Engineering, Electrical Engineering, Aerospace Engineering, Biomedical Engineering, Psychology, Music, Physics, Mathematics, and Architecture. The program began over 50 years ago and strengthened considerably in the 1960s and 1970s after Eugene Patronis, Ben Zinn, and Allan Pierce joined the faculty in the Schools of Physics, Aerospace Engineering, and Mechanical Engineering, respectively. Since then hundreds of students in acoustics have graduated and hold positions in academia and industry around the world. Currently the School of Mechanical Engineering has 11 academic faculty members with primary interest in acoustics and dynamics. Areas of research include architectural acoustics, psychoacoustics, noise control, environmental acoustics, sustainable systems design, underwater acoustics, bioacoustics, ultrasonics, active/passive control, fluid-structure interaction, nonlinear acoustics, acousto-optics, micromachined sensors and actuators, vibration of nonlinear and frictional systems, shock and vibration isolation, structural acoustics, wave propagation, and structural health monitoring. Masters and Ph.D. level programs are offered in addition to various undergraduate courses. The depth of knowledge at Georgia Tech facilitates a variety of collaborations, allowing students a multi-disciplinary education in the science and application of acoustics. Student interactions are further facilitated by a number of organizations on campus, including a recently established student chapter of the ASA.
Brazil’s first undergraduate course in acoustical engineering.
Authors: Paul Stephan , da Silva Andrey R. , Vergara Erasmo F. , da Paixão Dinara X.
Published: October 2010

The fact that the research on acoustics represents an important segment of science and a significant necessity of society is certainly commonplace among acousticians. In many situations, however, it is only marginally incorporated into the curricula of universities. This is particularly the case in the Brazilian educational and research institutions, mainly due to the lack of a comprehensive curriculum that accounts for basic education in acoustics, despite the enormous demand for acousticians in Brazil. To meet this demand, the Federal University of Santa Maria has begun, in the end of 2008, a dedicated 5-year undergraduate course in Acoustical Engineering to provide students with more than basic knowledge in acoustics, vibrations, and audio. Within the first four semesters the curricula are structured to provide fundamental knowledge for enginners with traditional engineering subjects such as math, physics, mechanics, electrical circuits, and the like, accompanied by disciplines concerning musical education for acoustical engineers (first to fourth semester) and issues related to human exposure to noise. Starting at the fifth semester education in acoustics, vibration, and audio is broadened each semester with disciplines like room acoustics, noise control, environmental acoustics, electroacoustics, numerical methods in acoustics, psychoacoustics, and so on. The talk will present the structure of the course as well as discuss challenges and difficulties.
A stiff mass-spring-chain model for piano strings.
Authors: Kuroda Junji , Smith Julius , Van Heusen Katarina , Perng Jack
Published: October 2010

The mass-spring chain allows accurate modeling of vibrating strings in all three spatial dimensions. [Rowland and Pask, Am. J. Phys. (1999).] However, such a model is for non-stiff strings. A stiff mass-spring string model is proposed, consisting of three or more cross-coupled parallel mass-spring chains.
Practical determination of acoustic parameters of the singing voice implemented in the interactive analysis software EVOCANTO.
Authors: Orduña-Bustamante Felipe , Gracida Olvera Gisela
Published: October 2010

Practical methods of analysis with low computational complexity are presented for the determination of acoustic parameters from radiated sound pressure spectra of sustained sung vowels. Sound spectra are analyzed in order to obtain the fundamental vocal source frequency F0 and its harmonics, the corresponding musical pitch, the first few “formant” frequencies F1, F2, possibly up to F5, that are apparent from the harmonic contour, a nominal vocal tract shape derived from (F1, F2), a measure of formant-to-harmonic tuning of F1 and F2, indication of the presence of a singer’s formant, and a measure of the rate of vibrato. Real-time determination and display of these parameters are integrated into the singing voice analysis software EVOCANTO, a graphical interactive didactic computer program which is intended as a teaching aid for singing tutors and students. Examples of the use of EVOCANTO are presented for typical male and female singing voice registers.