Results 11 to 20 of about 232,461 (350)

Impedance Tuning: A Method for Active Control of the Acoustic Boundary Conditions of Combustion Test Rigs

, 2009
Eine der größten Herausforderungen für die Entwicklung zukünftiger schadstoffarmer Gasturbinenkraftwerke ist die Gewährleistung eines stabilen Verbrennungsprozesses. Um die immer strikter werdenden Emissionsrichtlinien, vor allem hinsichtlich NOx, zu erfüllen, führte die Gasturbinenindustrie die Mager-Vormisch-Verbrennung ein.
Mirko R. Bothien
openaire   +4 more sources

Construction and testing of a modern acoustic impedance tube

, 2001
The acoustic impedance of a material describes its reflective and absorptive properties. Acoustic impedance may be measured in a wide variety of ways. This thesis describes the construction and testing of an acoustic impedance measurement tube which employs modem Fourier Transform techniques.
Sean P. O'Malley
openaire   +3 more sources

Dynamic force measurement techniques in split hopkinson pressure bar testing of low acoustic impedance materials used as armor interlayer materials

, 2012
GoreTM PolarchipTM heat insulating Teflon and Dow ChemicalsTM Voracor CS Polyurethane were characterized in this study by conducting compression tests at various strain rates. Quasi-static compression tests were done with a Shimadzu AG-X conventional test machine while two different modified Split Hopkinson Pressure Bar (SHPB) systems were used for ...
Ali Kıvanç Turan
openaire   +4 more sources

OS0717 Ultrasonic Testing Using Powder Coupling with Adjustable Acoustic Impedance

The Proceedings of the Materials and Mechanics Conference, 2012
Kazuya MORI, Kenji HASHIMOTO, Kazuhisa ERA   +2 more
openaire   +2 more sources

Analysis of wideband tympanometry in Ménière’s disease

Brazilian Journal of Otorhinolaryngology, 2022
Introduction: Endolymphatic hydrops is the pathophysiological substrate of Ménière’s disease. The changes in the inner ear, transmitted to the middle ear through changes in the ossicular chain mobility, can be quantified by wideband tympanometry, through
Gisela Andrea Yamashita Tanno, Mônica Alcantara de Oliveira Santos, Marcelo Tabosa Dutra Sanches, Alessandra Spada Durante, Kátia de Almeida, Marcella Scigliano Gameiro, Nayara Michelle Costa de Freitas Roque, Osmar Mesquita de Sousa Neto   +7 more
doaj   +1 more source

Wideband Acoustic Absorbance in Otosclerosis: Does Stapedotomy Restore Normal Tympanic Cavity Function?*

International Archives of Otorhinolaryngology, 2022
Introduction Otosclerosis is characterized by the fixation of the stapes to the oval window, thereby impairing acoustic signal absorbance. A commonly used surgical technique for improving hearing in cases of otosclerosis is stapedotomy.
Alessandra Spada Durante, Polyana Cristiane Nascimento, Katia de Almeida, Thamyris Rosati Servilha, Gil Junqueira Marçal, Osmar Mesquita de Sousa Neto   +5 more
doaj   +1 more source

Acoustic Experimental Technology for Aircraft Nacelle Liner

Aerospace, 2023
An aircraft nacelle acoustic liner is a key mean of aircraft noise reduction. The success of its design depends strongly on the development of experimental technology, which is generally divided into two stages: impedance eduction and the modal ...
Qun Yan, Dongwen Xue, Qinqin Mu, Jiafeng Yang, Xiang Gao, Wenchao Huang   +5 more
doaj   +1 more source

Middle ear resonance in infants: Age effects

International Archives of Otorhinolaryngology, 2012
Summary Introduction: The resonant frequency is the probe frequency in which susceptance is 0 due to the neutralization of the forces of mass and stiffness components that control the middle ear.
Karina Delgado André, Seisse Gabriela Gandolfi Sanches, Renata Mota Mamede Carvallo   +2 more
doaj   +3 more sources

A method for material characterization of sealing system elastomers using sound transmission loss measurements

Polymer Testing, 2022
The acoustic properties of sealing systems are essential for the noise control of new-generation vehicles and closure systems. Accurate characterization of the elastic elastomer properties is essential to perform acoustic analyses; however, this ...
Orçun Saf, Haluk Erol, Ali Erkin Kutlu
doaj   +1 more source

The Acoustic Performance of Natural Composites in Reducing Stress Levels: Textile Industry

Civil Engineering Journal, 2023
The porous characteristics of recycled natural fibres make them suitable for use as acoustic materials. Straw and water hyacinth fibres are natural materials that can potentially be used as composites in damping devices. This study evaluated the acoustic
M. P. Widjanarti, A. Probandari, .. Sumardiyono, .. Sunarto   +3 more
semanticscholar   +1 more source