Results 291 to 300 of about 440,511 (349)
On the Value of Acoustic Impedance Tests in the Clinic
International Journal of Audiology, 1971 Vilija M. Priede, R. R. A. Coles
semanticscholar +4 more sources
Comparison of the Two-Microphone Method and a Modal Decomposition Method for Acoustic Impedance Testing [PDF]
12th AIAA/CEAS Aeroacoustics Conference (27th AIAA Aeroacoustics Conference), 2006 Accurate duct acoustic propagation models are required to predict and mitigate radiated aircraft engine noise. These models ultimately rely on acoustic impedance measurements to characterize candidate engine nacelle liner materials. This paper compares two different methods for normal incidence acoustic impedance testing: the two-microphone method (TMM)
Todd Schultz +2 more
openaire +2 more sources
Modal Decomposition Method for Acoustic Impedance Testing in Rectangular Ducts [PDF]
44th AIAA Aerospace Sciences Meeting and Exhibit, 2006 Accurate duct acoustic propagation models are required to characterize and reduce aircraft engine noise. These models ultimately rely on measurements of acoustic impedance for candidate materials used in engine nacelle liners. This paper seeks to increase the frequency range of normal incidence acoustic impedance testing in square ducts by extending ...
Todd Schultz +2 more
openaire +2 more sources
Uncertainty Analysis of the Two-Microphone Method for Acoustical Impedance Testing
8th AIAA/CEAS Aeroacoustics Conference & Exhibit, 2002 This paper presents two methods for determining the experimental uncertainty of normal-incidence acoustic impedance measurements using the twomicrophone method (TMM). The first method is an analytical technique that extends standard first-order uncertainty methods to complex variables.
Todd Schultz +3 more
openaire +3 more sources
Modal decomposition method for acoustic impedance testing in square ducts
The Journal of the Acoustical Society of America, 2006 Accurate duct acoustic propagation models are required to predict and reduce aircraft engine noise. These models ultimately rely on measurements of the acoustic impedance to characterize candidate engine nacelle liners. This research effort increases the frequency range of normal-incidence acoustic impedance testing in square ducts by extending the ...
Mark Sheplak +2 more
openaire +4 more sources
Modal decomposition method for high-frequency acoustic impedance testing
The Journal of the Acoustical Society of America, 2005 Accurate duct acoustic propagation models are required to characterize and reduce aircraft engine noise. These models ultimately rely on measurements of acoustic impedance for candidate materials used in engine nacelle liners. This paper seeks to increase the frequency range of acoustic impedance testing by extending the standard two-microphone method (
Todd Schultz +2 more
openaire +3 more sources
The bulk acoustic properties of a porous medium, derived from a single impedance test
The Journal of the Acoustical Society of America, 1999 In the majority of engineering applications, porous sound absorbing media may be treated as equivalent fluids, with vibration of the solid skeleton being neglected. Most measurement techniques for the bulk acoustic properties of such media (e.g., complex characteristic impedance and propagation constant) involve tests on large samples of material ...
A. Cummings
openaire +3 more sources
Akustika, 2021 The paper discusses a simple and low-cost method to design four microphone impedance tube of measuring the acoustic properties of building materials. The acoustic properties of the material are defined by the reflection coefficient, absorption coefficient, and transmission coefficient.
Sourabh Dogra, Arpan Gupta
openaire +3 more sources
[The role of acoustic impedance test in the diagnosis for occupational noise induced deafness].
Zhonghua lao dong wei sheng zhi ye bing za zhi = Zhonghua laodong weisheng zhiyebing zazhi = Chinese journal of industrial hygiene and occupational diseases, 2018 Objective: To investigate the characteristics of acoustic impedance test and its diagnostic role for occupational noise induced deafness, in order to provide an objective basis for the differential diagnosis of occupational noise induced deafness. Methods: A retrospective study was conducted to investigate the cases on the diagnosis of occupational ...
L J Xue +5 more
openaire +3 more sources
[Clinical applications of acoustic impedance tests].
Annali di laringologia, otologia, rinologia, faringologia, 1975 This manuscript briefly outlines the most important areas of clinical impedance audiometry. The author has emphasized the use of impedance audiometry in differentiating different types of middle ear pathology and utilizing the stapedial reflex in the determination of malingering as well as an overall test of the auditory function of the auditory ...
Vittorio Colletti
openaire +3 more sources