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Results 401 - 450 of 1090
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Cobo Pedro - - 2007
Although hybrid passive-active absorption in impedance tubes has been widely analyzed, its study in more realistic conditions remains to be accomplished. This letter describes the practical measurement of the passive-active absorption coefficient in a free field. The passive absorber consists of a microperforated panel backed by an air cavity and ...
Zhang Yu - - 2007
PURPOSE: The present study was a methodological study designed to reveal the dynamic mechanisms of phonation instability pressure (PIP) using bifurcation analysis. Phonation pressure range (PPR) was also proposed for assessing the pressure range of normal vocal fold vibrations. METHOD: The authors first introduced the concept of bifurcation on the ...
Laukkanen Anne-Maria - - 2008
This study investigated the peak-to-peak (p-t-p) amplitude of the voice source as a function of fundamental frequency (F(0)). Nine males and nine females with or without singing training produced (1) a glissando from lowest to highest F(0) and back in their speaking range on /a:/ and (2) an ascending-descending scale ...
Björkner Eva - - 2008
The considerable voice timbre differences between musical theater (MT) and western operatic singers are analyzed with respect to voice source and formant frequencies in five representatives of each singer group. Audio, subglottal pressure (P(sub)), and electroglottograph (EGG) signals were recorded while the subjects sang a sequence of [pae:] syllables starting ...
Yokota Reiko - - 2007
Measurement of the pressure applied to the anterior region of the palate and incisor region of the mandible during thumb-sucking was carried out 3 female children. A polyethylene bag embedded with a high-sensitivity small pressure sensor was fixed on the ventral side of the thumb so that the baroreceptor could ...
Aydin Y - - 2007
The aim of this study was to evaluate subjective noise perception and objective parameters of circulation in the vicinity of the Frankfurt airport. Two areas were selected in which aircraft noise was the predominant source of noise (and was) created by planes induced by take off but not during landing. ...
Finnegan Eileen M - - 2009
The aim of this study is to determine how phonation is affected by the presence and by alteration in the position of the supraglottic structures. The study used three excised canine larynges. A series of pressure-flow experiments were completed first on the excised larynx with false folds and epiglottis intact, ...
Williams Warwick - - 2007
Some individuals must wear hearing protectors in order to reduce their noise exposure even after all other avenues of exposure control have been exhausted. However, is it reasonable to expect these individuals to wear earmuffs for long, continuous periods? Measurements of 39 commonly available earmuffs show that in all cases, ...
Searl Jeff - - 2007
OBJECTIVES: This study compared bilabial contact pressure (CPsp) and oral air pressure (Po) for /p/, /b/, and /m/ produced by tracheoesophageal (TE) versus laryngeal speakers. Nonspeech maximum bilabial contact pressures (CPmax) were measured to calculate the percentage of the range utilized for bilabial phonemes. METHODS: Ten TE speakers and 10 ...
van Iersel Maikel M - - 2007
The effect of hydrostatic pressure on chemical reactions induced by 20 kHz ultrasound has been studied using three different methods: the oxidation of potassium iodide, bubble cloud visualization studies, and sound attenuation measurements. The latter two have demonstrated that shielding of the ultrasonic wave is less pronounced at elevated pressures. ...
Bell Andrew - - 2007
It is widely thought that organisms detect sound by sensing the deflection of hair-like projections, the stereocilia, at the apex of hair cells. In the case of mammals, the standard interpretation is that hair cells in the cochlea respond to deflection of stereocilia induced by motion generated by a hydrodynamic ...
Jacobsen Finn - - 2007
Statistically optimized near field acoustic holography (SONAH) differs from conventional near field acoustic holography (NAH) by avoiding spatial Fourier transforms; the processing is done directly in the spatial domain. The main advantage of SONAH compared with NAH is that the usual requirement of a measurement aperture that extends well beyond ...
Braunschweig T - - 2008
An objective method for the diagnosis of functional dysphonias is presented. The mathematically motivated approach was evaluated on 71 female subjects with normal voice or functional dysphonia. Using digital high-speed recordings, the phonation onset process was recorded in real-time for 8-10 different sound pressure levels for each subject. From these ...
Garrel Renaud - - 2008
Well-known multimass models of vocal folds are useful to describe main behavior observed in human voicing but their principle of functioning, based on harmonic oscillation, may appear complex. This work is designed to show that a simple one-mass model ruled by laws of relaxation oscillation can also depict main behavior ...
Alipour Fariborz - - 2007
The purpose of this study was to examine the aerodynamic and acoustic effects of the false vocal folds and the epiglottis on excised larynx phonation. Several canine larynges were prepared and mounted over a tapered tube that supplied pressurized, heated, and humidified air. Glottal adduction was accomplished either by using ...
Toll Nathanial J - - 2007
The effects of barometric pressure and earth tide changes are often observed in ground water level measurements. These disturbances can make aquifer test interpretation difficult by masking the small changes induced by aquifer testing at late times and great distances. A computer utility is now available that automatically removes the ...
Choi Hyun Seok HS Department of Biomedical Engineering, College of Health Science, Yonsei University, Wonju, South Korea. - - 2007
Motion artifacts can degrade the quality of data measured. In this paper, we suggest a capacitive sensor application which is able to be fabricated easily and employed for adaptive filtering. When the motion artifacts occur, the capacitance varies as well. Thereby, the capacitance data coincide with the motion artifacts. The ...
Kim Jun Sik - - 2007
The tongue has important roles in deglutition, speech, airway protection, taste, and sexual function, and its amputation is very serious. Using supermicrosurgical techniques, we replanted successfully a patient's tongue, the distal part of which had been amputated by the bite of another person, through the anastomosis of a blood vessel ...
Holmberg Eva B - - 2007
This study discusses phonetogram recordings as a tool in the voice clinic. It reports experiences during recordings and changes in measures across voice therapy for women with vocal fatigue. Phonetogram data are discussed along with subglottal pressure measurements and subjective evaluations of voice function and quality. Assessments were made pre-, ...
Horácek Jaromír - - 2007
The maximum impact stress at the contact of the vocal folds achieved during the oscillation cycle was estimated in phonation using an aeroelastic model of voice production. Relations of impact stress to the lung pressure, fundamental frequency of self-oscillations, prephonatory glottal width, sound pressure level generated at the end of ...
Laukkanen Anne-Maria - - 2007
Vocal exercises that increase the vocal tract impedance are widely used in voice training and therapy. The present study applies a versatile methodology to investigate phonation during varying artificial extension of the vocal tract. Two males and one female phonated into a hard-walled plastic tube (phi 2 cm), whose physical ...
Wolff, M.
This paper reports on a study of applying an HMM-based labeler along with a tailored feature extraction to Korotkoff sounds. These sounds can be heard through a stethoscope during the auscultatory blood pressure measurement usually done at medical practices. While this method works well when the patient is at rest, ...
Ketelslagers K - - 2007
The purpose of this study was to determine the clinical value of subglottic pressure (SGP) in normal and dysphonic subjects. "The airway interrupted method" was used to measure the intra-oral pressure. Voice samples from 60 healthy subjects and 79 dysphonic patients were recorded under normal conditions of pitch and intensity. ...
Ungar Eric E - - 2006
The noise reductions provided by capsules consisting of uniform cylindrical shells whose two ends are closed off by like circular plates are analyzed for the low-frequency regime in which a capsule acts quasi-statically, much like a pressure vessel. The change in the confined volume is determined from the structural deflections ...
Werth Alexander J - - 2006
The role of cranial morphology in the generation of intraoral and oropharyngeal suction pressures in odontocetes was investigated by manipulating the jaw and hyolingual apparatus of submerged heads of three species presenting varied shapes. Hyoid and gular muscles were manually employed to depress and retract the tongue. Pressures were recorded ...
Grolman Wilko - - 2007
BACKGROUND: In laryngectomized patients, tracheoesophageal voice generally provides a better voice quality than esophageal voice. Understanding the aerodynamics of voice production in patients with a voice prosthesis is important for optimizing prosthetic designs and successful voice rehabilitation. OBJECTIVES: To measure the aerodynamics and sound intensity in tracheoesophageal voice production. STUDY ...
Döllinger Michael - - 2006
OBJECTIVE: This study investigated the influence of epilarynx area on an excised human vocal fold during phonation. STUDY DESIGN: A hemilarynx set-up using an excised human larynx was used. An artificial vocal tract with an epilarynx tube of variable cross-sectional area was attached. High-speed imaging was performed and standard phonatory ...
Mendez J M - - 2006
In this work we analyze the pressure motor patterns used by canaries (Serinus canaria) during song, both in the cases of males and testosterone treated females. We found a qualitative difference between them which was not obvious from the acoustical features of the uttered songs. We also show the diversity ...
Huckabee Maggie-Lee - - 2006
OBJECTIVE: To evaluate the influence of tongue-to-palate pressures on submental muscle contraction and oral and pharyngeal pressure dynamics during effortful swallowing maneuver. DESIGN: Comparative analysis of 2 task strategies on biomechanic measures of swallowing. SETTING: Research laboratory in a free-standing research facility. PARTICIPANTS: Consecutive volunteer sample of 20 healthy participants ...
Luschei Erich S - - 2006
Laryngeal muscle electromyography (EMG) and measures of the behavior of the respiratory system have been made during spontaneous laughter in two groups of subjects. The smaller group also had a direct measure of tracheal pressure during this behavior. Laryngeal adductors such as the thyroarytenoid (TA) and lateral cricoarytenoid (LCA) exhibited ...
Räsänen Jukka O - - 2006
We evaluated the acoustic frequency response of endotracheal tubes (ETs) to assess their effect on respiratory system sound transmission studies. White noise 150-3300 Hz was introduced into 4.0-, 6.0-, and 8.0-mm ETs and recorded at their proximal and distal ends. Four tubes of each size were studied at their original ...
Foldyna Josef - - 2006
Recently, substantial attention is paid to the development of methods of generation of pulsations in high-pressure systems to produce pulsating high-speed water jets. The reason is that the introduction of pulsations into the water jets enables to increase their cutting efficiency due to the fact that the impact pressure (so-called ...
Huang Wei - - 2006
In this paper, the relation between the ambient radius R(0) of the acoustic cavitation bubble and its driving pressure was investigated by an improved method. The evolution of the bubble was gained with a long-distance microscope and a bundle of 532 nm laser switched by an acousto-optic modulator. The ambient ...
Tao Chao - - 2006
Vocal fold impact pressures were studied using a self-oscillating finite-element model capable of simulating vocal fold vibration and airflow. The calculated airflow pressure is applied on the vocal fold as the driving force. The airflow region is then adjusted according to the calculated vocal fold displacement. The interaction between airflow ...
Kelly James F - - 2006
A time-space decomposition approach is derived for numerical calculations of the transient nearfield pressure generated by a circular piston. Time-space decomposition analytically separates the temporal and spatial components of a rapidly converging single integral expression, thereby converting transient nearfield pressure calculations into the superposition of a small number of fast-converging ...
van Kempen E - - 2006
Conclusions that can be drawn from earlier studies on noise and children's blood pressure are limited due to inconsistent results, methodological problems, and the focus on school noise exposure. To investigate the effects of aircraft and road traffic noise exposure on children's blood pressure and heart rate. Participants were 1283 ...
Li Sheng - - 2006
Vocal fold geometry plays an important role in human phonation. A wide range of inferior and superior vocal fold surface angles has been shown to be present during phonation [Nanayakkara, Master's thesis, Bowling Green State University, Bowling Green, OH (2005)]. This study explored how these angles affect pressure distributions on ...
Lu I-Jung - - 2006
Our recent studies show that intravenous administration of capsaicin induces enhancement of the intralaryngeal thyroarytenoid (TA) branch but a reduction of the intralaryngeal abducent branch, suggesting that the glottis is likely closed by capsaicin. The aim of the present study was to examine whether the glottis is adducted by intravenous ...
Cooper Brenton G - - 2006
Precisely timed behaviors are central to the survival of almost all organisms. Song is an example of a learned behavior under exquisite temporal control. Song tempo in zebra finches (Taeniopygia guttata) is systematically modified depending on social context. When male zebra finches sing to females (directed), it is produced with ...
Lombard Lori E - - 2007
A hypophonic voice, characterized perceptually as weak and breathy, is associated with voice disorders such as vocal fold atrophy and unilateral vocal fold paralysis. Although voice therapy programs for hypophonia typically address the vocal folds or the sound source, twang voice quality was examined in this study as an alternative ...
Sümer Sarp Korkut - - 2006
A considerable number of the combine harvesters in Turkey are rather old and used without cabs resulting in unhealthy working conditions for their operators. Noise is one of the detrimental factors. This study deals with determining and comparing the noise exposed on the operators of the combines with and without ...
Moeini Vahid - - 2006
In this paper, we derive a new regularity for dense fluids, both compressed liquids and dense supercritical fluids based on the Lennard-Jones (12-6) potential function and using speed of sound results. By considering the internal pressure by modeling the average configurational potential energy, and then taking its derivative with respect ...
Li Sheng - - 2006
Vocal fold geometry plays an important role in human phonation. The intraglottal quasi-steady pressure and velocity distributions depend upon the shape, size, and diameter of the glottis. This study reports the effects of the variation of glottal shapes on intraglottal pressures and velocities using a Plexiglas model with a glottis ...
Ferasin L - - 2007
A six-month-old, entire female, Irish setter was presented with a two-month history of progressive hindlimb weakness and collapse on exercise. Thoracic auscultation revealed a soft systolic murmur and a split second heart sound. Differential cyanosis and polycythaemia were not observed. Right-to-left shunting patent ductus arteriosus (r-PDA) was confirmed on contrast ...
Schwandt Leonora Q - - 2006
Tracheoesophageal voice prostheses need to be replaced due to increased airflow resistance or retrograde leakage of fluid into the trachea as a consequence of biofilm formation. Previous in vitro studies show a change of aerodynamic features of biofilm covered voice prostheses after removal of the prostheses out of the patient. ...
Ahart Muhtar - - 2006
High-pressure micro-Brillouin scattering is employed to investigate the pressure dependence of the sound velocity, refractive index, equation of state, and mechanical properties of amorphous BeH2. The refractive index n has been determined by using two scattering geometries (70 degrees and 180 degrees). The equation of state is deduced from the ...
Zuckerwar Allan J - - 2006
A free-field (FF) substitution method for calibrating the pressure sensitivity of microphones at frequencies up to 80 kHz is demonstrated with both grazing and normal-incidence geometries. The substitution-based method, as opposed to a simultaneous method, avoids problems associated with the nonuniformity of the sound field and, as applied here, uses ...
Zhang Xin-Yu XY Joint Res. Center for Biomed. Eng., Chinese Univ. of Hong Kong, Shatin, Hong - - 2006
Previous studies have shown that it is possible to estimate pulmonary and systemic blood pressure using the spectral information of the second heart sound. A mathematical model for the vibration of the closed aortic valve is proposed in the paper with the introduction of the nonlinear elasticity of the aortic ...
Kodaira Y - - 2006
The aim of this study was first to investigate whether the covering of the palatal mucosa with a denture base affects or not the bolus-propulsion time, and second if there was such an effect then investigate the possible contributory factors which have influence on the propulsion time. The propulsion time ...
Yoshida Mitsuyoshi - - 2006
The tongue plays a key role in oropharyngeal swallowing. It has been reported that maximum isometric tongue pressure decreases with age. The risk for dysphagia resulting from low tongue strength remains unclear. This study was designed to reveal the relationship between tongue pressure and clinical signs of dysphagic tongue movement ...
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