820 resultados para thermal distortion


Relevância:

20.00% 20.00%

Publicador:

Resumo:

This paper presents information on the reliability of distortion product otoacoustic emissions in children with profound sensorineural hearing losses.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

This paper presents a study investigating the relationship between tympanometry measures of the middle ear and Distortion Product Otoacoustic Emissions (DPOAE) screening, suggesting that using a combination of the two methods in pediatricians’ offices would result in fewer inappropriate referrals for comprehensive hearing evaluations.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

The purpose of this study was to examine objective and subjective distortion present when frequency modulation (FM) systems were coupled with four digital signal processing (DSP) hearing aids. Electroacoustic analysis and subjective listening tests by experienced audiologists revealed that distortion levels varied across hearing aids and channels.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

This paper studies the test-retest reliability of distortion product otoacoustic emissions (DPOAE) in newborns in a neonatal intensive care unit.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

This paper describes a project which set up a system to measure distortion product otoacoustic emissions (DPOAEs) in the Sprague Dawley rat and to conduct a pilot study to measure the development of DPOAEs as a function of age.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

This paper discusses a study done of neonates to determine the differences between ABR and DPOE for hearing screening.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

This paper discusses the effect of noise exposure on high school aged boys' hearing levels and how to measure the effects.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

This paper studies the relationship between hearing sensitivity and the presence of otoacoustic emissions by examining the variability of same ear emissions in a group of normal-hearing subjects.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

This paper examines distortion product otoacoustic emissions (DPOAEs) used to test peripheral auditory function, and how noise level in the ear affects the detectability of DPOAEs. The study examines the clinical feasibility of different time averages at different frequencies on the noise floor.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

This paper is a review of a study on distortion product emissions in normal hearing chinchillas.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

This paper discusses the distortion-product otoacoustic emissions (DPOAE) of chinchillas when exposed to noise.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Recovery of distortion product otoacoustic emissions in the bullfrog after noise exposure does not correlate with hair cell damage noted on the amphibian papilla.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Reaction Injection Moulding (RIM) is a moulding technology used for the production of large size and complex plastic parts. The RIM process is characterized essentially by the injection of a highly reactive chemical system (usually polyurethane) and fast cure, in a mould properly closed and thermally controlled. Several studies show that rapid manufacturing moulds obtained in epoxy resins for Thermoplastic Injection Moulding (TIM) affect the moulding process and the final properties of parts. The cycle time and mechanical properties of final parts are reduced, due to a low thermal conductivity of epoxy materials. In contrast, the low conductivity of materials usually applied for the rapid manufacturing of RIM moulds, increase the mechanical properties of final injected parts and reduce the cycle time. This study shows the effect of the rapid manufacturing moulds material during the RIM process. Several materials have been tested for rapid manufacturing of RIM moulds and the analysis of both, temperature profile of moulded parts during injection and the cure data experimentally obtained in a mixing and reaction cell, allow to determine and model the real effect of the mould material on the RIM process.

Relevância:

20.00% 20.00%

Publicador:

Relevância:

20.00% 20.00%

Publicador:

Resumo:

We have investigated the adsorption and thermal decomposition of copper hexafluoroacetylacetonate (Cu-11(hfaC)(2)) on single crystal rutile TiO2(110). Low energy electron diffraction shows that room temperature saturation coverage of the Cu-II(hfac)(2) adsorbate forms an ordered (2 x 1) over-layer. X-ray and ultra-violet photoemission spectroscopy of the saturated surface were recorded as the sample was annealed in a sequential manner to reveal decomposition pathways. The results show that the molecule dissociatively adsorbs by detachment of one of the two ligands to form hfac and Cu-1(hfac) which chemisorb to the substrate at 298 K. These ligands only begin to decompose once the surface temperature exceeds 473 K where Cu core level shifts indicate metallisation. This reduction from Cu(I) to Cu(0) takes place in the absence of an external reducing agent and without disproportionation and is accompanied by the onset of decomposition of the hfac ligands. Finally, C K-edge near edge X-ray absorption fine structure experiments indicate that both the ligands adsorb aligned in the < 001 > direction and we propose a model in which the hfac ligands adsorb on the 5-fold coordinated Ti atoms and the Cu-1(hfac) moiety attaches to the bridging O atoms in a square planar geometry. The calculated tilt angle for these combined geometries is approximately 10 degrees to the surface normal.