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Zuckerwar Allan J - - 2008
Calibration of the pressure sensitivity of measurement microphones in a coupler requires by definition that the incident pressure be uniform over the surface of the microphone diaphragm. This requirement is readily satisfied at frequencies up to the cut in frequencies of the radial modes and, if the microphone is not ...
Riner Joshua - - 2008
An acoustic method to check the validity of Hertz's law and assess the actual collision force law in granular media is proposed. The technique uses a microphone to detect the sound produced by collisions between solid polypropylene balls. The impact is observed to produce an underpressure followed by an overpressure. ...
Ludwigsen Daniel - - 2008
The end correction that accounts for the inertial impedance at the open end of a pipe is a widely used refinement to lumped-element models, and many variations have been investigated. This study measures the end correction for 1 m closed-open pipes of varying diameters, exposed to a single-frequency external sound ...
Tack Johannes W - - 2008
BACKGROUND: A newly developed artificial voice source was clinically evaluated in laryngectomized women for voice quality improvements. The prosthesis was placed in a commercially available, tracheoesophageal shunt valve. METHODS: In 17 subjects, voice-producing element (VPE) prototypes were compared with the subject's regular tracheo-esophageal shunt voice in a randomized cross-over trial. ...
Chone Carlos Takahiro - - 2008
OBJECTIVE: To evaluate the utility of computerized manometry (CM) to identify pharyngoesophageal segment (PES) spasm during tracheoesophageal speech. STUDY DESIGN: Prospective clinical, controlled study. SUBJECTS AND METHODS: Intraluminal pressures of the PES were collected in 12 tracheoesophageal speakers without spasm and 8 tracheoesophageal speakers with PES spasm before and after ...
da Costa-Goncalves Andrey C - - 2008
Spinophilin controls intensity/duration of G protein-coupled receptor signaling and thereby influences synaptic activity. We hypothesize that spinophilin affects blood pressure through central mechanisms. We measured blood pressure and heart rate in SPL-deficient (SPL(-/-)), heterozygous SPL-deficient (SPL(+/-)), and wild-type (SPL(+/+)) mice by telemetry combined with fast Fourier transformation. We also assessed ...
Alipour Fariborz - - 2009
To determine the aerodynamic and acoustic effects due to a sudden change from chest to falsetto register or vice versa. It was hypothesized that the continuous change in subglottal pressure and flow rate alone (pressure-flow sweep [PFS]) can trigger a mode change in the canine larynx. Ten canine larynges were ...
Park Jong Beom - - 2008
The influence of a posterior gap on the airflow through the human glottis was investigated using a driven synthetic model. Instantaneous orifice discharge coefficient of a glottal shaped orifice was obtained from the time-varying orifice area and the velocity distribution of the pulsated jet measured on the axial plane using ...
Jiang Jack J - - 2008
Vocal fold vibration is associated with four distinct vibratory patterns: those of the right-upper, right-lower, left-upper, and left-lower vocal fold lips. The purpose of this study was to propose a least squares method to quantify the vibratory properties of each of the four vocal fold lips via videokymography (VKG). This ...
Hatch Leila - - 2008
In 2006, we used the U.S. Coast Guard's Automatic Identification System (AIS) to describe patterns of large commercial ship traffic within a U.S. National Marine Sanctuary located off the coast of Massachusetts. We found that 541 large commercial vessels transited the greater sanctuary 3413 times during the year. Cargo ships, ...
Perincek Seher - - 2009
Design requirements for industrial size ultrasound bath for textile treatments have been determined. For this purpose, effects of sound pressure level, bath temperature, bath volume, textile material type and hydrophility degree of fabric were examined extensively. Finite element analysis (FEA) was used to investigate spacing and alignment of the ultrasound ...
Hoffman Matthew R - - 2009
Current noninvasive measurement of subglottal pressure using airflow interruption often produces inconsistent results due to the elicitation of audio-laryngeal reflexes. Auditory feedback could be considered as a means of ensuring measurement accuracy and precision. The purpose of this study was to determine if auditory masking could be used with the ...
Fulcher Lewis P - - 2010
An experimental study of the pressure distributions in an asymmetric larynx, hereafter referred to as a hemilarynx, was carried out at a glottal diameter of 0.04 cm and transglottal pressures of 3, 5, 10, 20, and 40 cm H(2)O. In each case, the glottal wall "on the left" was chosen ...
Chang C H - - 2008
Compared to single-pressure models, multipressure multiphase flow models require additional closure relations to determine the individual pressures of the different phases. These relations are often taken to be evolution equations for the volume fractions. We present a rigorous theoretical framework for constructing such equations for compressible multiphase mixtures in terms ...
Alipour Fariborz - - 2008
The purpose of this study was to examine the phonatory characteristics of pig, sheep, and cow excised larynges and to find out which of these animal species is the best model for human phonation. Excised pig, sheep, and cow larynges were prepared and mounted over a tapered tube on the ...
Yagi Saiko - - 2008
Swallowing is a reflex that receives sensory information from the peripheral nerves and from the cerebral cortex. The aim of the present study was to investigate whether the sensory input from anterior teeth affects the functional characteristics of tongue pressure applied against the hard palate during swallowing. Subjects were eight ...
Pierucci Mauro - - 2008
Ride quality in an elevator is the latest "hot topic" in elevator design and construction. In skyscrapers being built in Asia, Dubai and the US, the new elevators travel close to and beyond 10ms. The rides to the highest floors will last well over one minute. From a comfort point ...
Zhang Zhaoyan - - 2008
The influence of the body and cover stiffnesses on phonation onset and the resulting vibration pattern was investigated in a body-cover continuum model of the vocal folds. An eigenvalue analysis was performed to obtained phonation onset characteristics. The analysis showed that, with increasing body-cover stiffness ratio, both the phonation threshold ...
Barney Anna - - 2008
A physical model, built to investigate the aeroacoustic properties of voiced fricative speech, was used to study the amplitude modulation of theturbulence noise it generated. The amplitude and fundamental frequency of glottal vibration, relative positions of the constriction and obstacle, and the flow rate were varied. Measurements were made from ...
Sygulska Anna - - 2008
The paper concerns the influence of the stage layout on the acoustic properties of the auditorium of the Grand Theatre in Poznan. An experimental investigation and a numerical calculation were carried out. During the experimental investigation three cases were analyzed. Firstly, the stage was prepared for a concert (acoustical shell), ...
Babisch Wolfgang - - 2008
The HYENA study is a multi-centred study regarding the effects of aircraft noise and road traffic noise on blood pressure (BP) which was funded by the European Community. Study subjects were 4,861 males and females aged between 45 and 70 years, who had lived for at least 5 years in ...
Fuchs Susanne - - 2008
Intraoral pressure changes during speech production are a result of different factors, such as articulatory movements (place and manner of articulation), subglottal pressure, and laryngeal-oral coordination. This study attempts to provide a better understanding of the relation between aerodynamics and articulation in single voiceless consonants and their combinations. We gathered ...
Tayong Rostand - - 2008
When submitted to relatively high sound pressure amplitudes, Micro Perforated Panels (MPP) are influenced by certain effects, which are non negligible (vibration of the panel, end radiation and also proximity of the perforations). A model of the total impedance of the MPP is derived from the sum of the contributions ...
Stevenson Samuel - - 2008
It is widely accepted that the starting transient is an extremely significant perceptual feature of musical sound. For players, the ease with which a note can be started on a particular instrument is also of great importance. However, until recently research has concentrated on the analysis of steady state sounds ...
Santin Mathieu - - 2008
Dilute solutions of Optison and Definity were studied using a passive cavitation detector (PCD) with a 2.8-MHz transmitter and 13-MHz receiver. The dilution was such that each received signal should, on average, arise from a single microbubble. Several hundred microbubble responses were acquired at each of three rarefactional pressures (1.6+-0.2, ...
Daridon Jean Luc - - 2008
The thermophysical properties of pure substances in fluid state as functions of temperature and pressure are of great interest not only for industrial applications (for example in the oil and gas industry), but also for fundamental aspects in view of developing models for an accurate representation of dense fluids. Now ...
Horodysky Andrij Z - - 2008
Sciaenid fishes are important models of fish sound production, but investigations into their auditory abilities are limited to acoustic pressure measurements on five species. In this study, we used auditory brainstem response (ABR) to assess the pressure and particle acceleration thresholds of six sciaenid fishes commonly found in Chesapeake Bay, ...
Horvat Marko - - 2008
As a part of an extensive ongoing research on reverberation time measurements, efforts have been made to find an impulse-like source that will comply with certain demands concerning its spectral content and sound pressure levels it can provide. Although the relevant standards state that such kind of sources should be ...
Koga Yuichiro - - 2008
We propose a method for analysing of the acoustic characteristics of compact acoustic reproduction systems with Three-Dimensional FDTD method. We reproduce actual structure of compact acoustic reproduction systems and take the frequency characteristic of sound pressure level at a point with Three-Dimensional FDTD method. To compare the frequency characteristic of ...
Bader Rolf - - 2008
The vibration of a reed of a saxophone is calculated using a 2D model of the mouth cavity, the mouth piece and the reed. The time-dependent Finite-Element calculation takes the flow-structure interaction into account and changes the geometry of the flow according to the reed vibration in time. The model ...
Paulsen Reimer - - 2008
The degree to which employees on construction sites are exposed to noise often depends on a variety of individual activities. The calculation of the average noise exposure for different construction trades in this sector calls for an enhanced level of work analysis and measurement. Recommended here are personal measurements with ...
Ljunggren Fredrik - - 2008
This paper relates to building acoustic measurement inside a two-story office house. The construction, which is known as lightweight, is prefabricated in volumes at a factory and is then transported to the building yard for assembling. It is build up of a wooden frame with particle boards and plaster boards ...
Fulcher Lewis P - - 2008
Pressure distributions were obtained with a static physical model (M5) at diameters d = 0.005, 0.01, 0.02, 0.04, 0.08, 0.16, and 0.32 cm for converging angles of 5, 10, 20, and 40 degrees. At each diameter and angle, transglottal pressures typically ranged from 3 to 15 cm H(2)O. For each ...
Van Renterghem Timothy - - 2008
In this paper, the finite-difference time-domain method is used to study sound propagation over a green roof in an urban situation. Sound propagation between adjacent city canyons is considered, and the focus is on the reduction of the sound pressure level in the non-exposed canyon due to the presence of ...
Baldwin Ann Linda - - 2008
OBJECTIVES: To determine whether application of Reiki to noise-stressed rats can reduce their heart rates (HRs) and blood pressures. RATIONALE: In a previous study, we showed that exposure of rats to 90 dB white noise for 15 minutes caused their HRs and blood pressures to significantly increase. Reiki has been ...
Koenig Laura L - - 2008
Phonation requires that tracheal pressure remain higher than intraoral pressure (Pio). In obstruent consonants, a major constriction in the upper vocal tract yields an increase in Pio, inhibiting phonation. The degree of Pio increase in consonants varies as a function of laryngeal and supraglottal apertures. Voiceless stops involve a rapid ...
Raghukumar Kaustubha - - 2008
A first-order Born approximation is used to obtain the pressure sensitivity of the received signal to small changes in medium sound speed. The pressure perturbation to the received signal caused by medium sound speed changes is expressed as a linear combination of single-frequency sensitivity kernels weighted by the source signal ...
Henrich Nathalie - - 2008
In lyrical singing, two principal laryngeal mechanisms are used to produce all the notes across the singer's tessitura. Laryngeal mechanisms M1 and M2 are characterised by a greater and lesser vibrating mass respectively. Different timbres between the two are at least partly explained by their different glottal behaviours. However, different ...
Park Jong Beom - - 2008
The glottal displacement flow is a volume flow induced by the motion of the vocal folds in the absence of transglottal pressure. This source may eventually contribute to the radiated sound, in particular during glottal opening. The volume source strength was numerically computed for a time-varying rigid M5 geometry, and ...
Ryherd Steve - - 2008
The purpose of this project was to investigate the effects of the wearer's voice as a dominant sound source on body-mounted noise dosimeters in medium-level acoustic environments. Noise dosimeters provide a convenient method of quantifying an occupant's acoustical exposure. In recent years, interest in personal noise exposure has expanded beyond ...
Kragh Jorgen - - 2008
In 1999 three different types of two-layer porous asphalt pavement with 5 mm or 8 mm maximum aggregate in the top layer were built in a city street in Copenhagen. A section with dense asphalt concrete was built as a reference. The pavements have been monitored since then. The initial ...
Lucero Jorge C - - 2008
Several past studies have used laryngeal andor upper vocal tract models to explore aerodynamic control during production of obstruent consonants, yet many aspects of such control remain unclear. Of particular interest in this work is how varying laryngeal and vocal tract dimensions such as occur among men, women, and children ...
Rosenkrantz Eric - - 2008
The impedance of gas contained between two plane walls is a periodic function of the frequency. The frequency interval between two resonances of the gas is equal to c2D. Furthermore, the amplitude of the resonances is proportional to the pressure. We describe a signal processing to easily deduce the speed ...
Barney Anna - - 2008
During voiced speech the source of sound production arises from the vibrations of the vocal folds within the larynx. In order to terminate these vibrations it is necessary either to adduct the vocal folds to produce a forced closure or to reduce the pressure drop across them to below a ...
Borucki Sebastian - - 2008
The subject matter of the research work presented in this paper refers to the measurements of the values of the acoustic pressure levels (noise) occurring around a main feeding-point aerial substation adjacent to apartment buildings. The paper presents the values of the noise accompanying the particular power devices, mainly transformers, ...
Lucero Jorge C - - 2008
The dynamical principles of the vocal fold oscillation at phonation were set forth by Titze (I. R. Titze, J. Acoust. Soc. Am. 83, 1536-1552 , 1988), by representing motion of the tissues as a surface wave propagating in the direction of the airflow. An important result of his work was ...
Schmidt Sebastian - - 2008
Equal-loudness contours represent the relationship of loudness perception and sound pressure at the ear. Usually, the reference pressure is defined with a standardised calibration procedure. Individual ear canal characteristics significantly influence the contours, resulting in peaks and notches. By choosing the eardrum pressure as reference for the perception measurements, individual ...
Bailly Lucie - - 2008
Period-doubling occurrences have been found during singing phonations such as Mongolian Kargyraa throat singing or Sardinian A Tenore Bassu singing. The combined vibrations of vocal folds and ventricular bands have been observed during the production of such low-pitch bass-type sounds. The present study aims at better understanding the physical interaction ...
Lee Pyoung Jik - - 2008
A procedure to convert the floor impact sound level of the bang machine as well as the tapping machine into that of the impact ball was suggested. Because the bang machine has been the only standard heavy-weight impact source for a long time in Japan and Korea, much of its ...
Honda Kiyoshi - - 2008
In the production of voiceless fricatives, the airflow passing through the vocal tract is controlled by reciprocal open-close patterns of the glottal and oral constriction. In order to observe such coordinated patterns, the authors have developed a combined method using a non-invasive (external-lighting and sensing) photoglottographic (ePGG) technique and a ...
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