Global ETD Search
Search theses and dissertations gathered from participating repositories worldwide. Every result links back to the library that holds it. No account is needed.
Results
Showing 1 to 20 of 22 for “"Laser-Doppler-Vibrometry"”.
-
Three-dimensional velocity extraction using laser Doppler vibrometry
… also need to be measured. Now with the use of a Laser Doppler Vibrometer the development of a method to measure three-dimensional velocities has provided the ability to measure in-plane velocities accurately. This thesis outlines the methods used for such three-dimensional extraction and gives an …
-
Laser Doppler Vibrometry Based Remote Sensing for Active Noise Control
… limit the performance of many ANC applications. Laser Doppler vibrometry, which works on the principle of optical interferometry, has been widely used in to measure vibrations in many vibro-acoustic applications. Yet, the developed instrument, laser Doppler vibrometer (LDV), has little been …
-
Information Processing for Biological Signals: Application to Laser Doppler Vibrometry
… of recording bio-mechanical activity using a Laser Doppler Vibrometer. The LDV measures surface velocity on the basis of the Doppler shift. This device is targeted on the neck overlying the carotid artery, and the proximity of the carotid to the skin results in a strong signal. Vibrations and …
-
Hydrogel Design Optimization for Measuring Ultrasound Using Laser Doppler Vibrometry
… benefit from a non-contact ultrasound system. Laser ultrasound (LUS) imaging offers potential advancements over conventional ultrasound, especially in achieving highresolution imaging of tissue structures and the elimination of liquid coupling mediums and probe-to-body contact. The thesis …
-
Development of a Novel Thermal Shock test for isostatically Pressed Carbon-Bonded Refractories
… such as digital image correlation (DIC) and laser Doppler vibrometry (LDV), were employed. Because of the novelty of Laser Doppler Vibrometry for refractories damage assessment, the outputs of this method were validated against acoustic-emission signals recorded during stress-strain cycles in …
-
Static Misalignment Effects is a Self-Tracking Laser Vibrometry System for Rotating Bladed Disks
The application of laser Doppler vibrometry to high speed rotating structures has been hampered by technical limitations. Whereas full-field three-dimensional velocity measurements can be made on stationary structures, the capability on rotating structures is limited to low speed, one-dimensional, …
-
Evaluation of optical techniques applied to online turbomachinery blade vibration measurements
… analyzing turbomachine blade vibrations, such as Laser Doppler Vibrometry (LDV) and photogrammetry. Both techniques have been successfully used to analyze vibrations of structures. Photogrammetry is a full-field measurement technique which allows for non-intrusive simultaneous measurement of …
-
Material, acoustic, and mechanical properties of mosquito and midge antennae
… hearing in insects. To this end, Confocal Laser Scanning Microscopy (CLSM), Finite Element Modelling (FEM) and Laser Doppler Vibrometry (LDV) were employed. The combination of the first two allows, in absence of prior knowledge of the material properties of mosquito or midge antennae, to …
-
Effect of Vibration of Unconsolidated Sand on the Performance of Interferometric Vibration Sensors
… traditional contact sensors are not desired. Laser Doppler vibrometers (LDV) and digital speckle pattern interferometers are studied in this thesis. The working principle of laser Doppler vibrometry and digital shearography is described. The effect of vibration of the unconsolidated sand on …
-
The effect of smooth muscle antagonists on the sound-induced motion of the tympanic membrane
… study two measurements, cochlear response and Laser Doppler Vibrometry, were used to assess the sound-induced velocity of the tympanic membrane of the gerbil before and after application of saline and varying concentrations of three smooth muscle antagonists (sodium orthovanadate, …
-
Middle ear pressure gain and cochlear input impedance in the chinchilla
… VS measurements were performed using single-beam laser-Doppler vibrometry; PV was measured with fiber optic pressure sensors like those described by Olson [JASA 1998; 103: 3445-63]. Accurate in-vivo measurements of PV are limited by anatomical access to the vestibule, the relative sizes of the …
-
Amphibian communication: Coupling of acoustic systems to the medium at the air-water interface
… and body walls constantly submerged. Using laser Doppler vibrometry, peak vibrations of female eardrums were found to be centered at about 3.5 kHz in air, but dropped to about 1.4 kHz underwater. The peak velocity of the eardrum was about 0.2 mm/s in air and 0.04 mm/s in water when …
-
THE INFLUENCE OF THE MICROENVIRONMENT OF HEALTHY AND TUMORAL CELLS
… combination of decellularization procedures and Laser Microdissection (LMD) and tested against tumoral rat cell line. As reference, we also performed force spectroscopy experiments using AFM spherical probes functionalized with the two main ECM proteins, laminin and fibronectin. Native ECM probes …
-
Biomechanical and neurophysiological investigation of insect tympanal organs
… of various species and orders of insect using laser Doppler vibrometry. The results were then compared between species, including the different structures and also the membrane mechanics. This chapter results highlights the different structures and also the range of frequencies that each …
-
Functional measurements of ear pathology in patients and cadaveric preparations
… Measurements of ossicular motion using laser Doppler vibrometry were also made in the same patients in order to compare the diagnostic utility of this well studied method to that of R. Using this patient information, multiple diagnostic uses and possibilities were explored, which showed …
-
Information Theoretic Methods For Biometrics, Clustering, And Stemmatology
… systems. We develop two biometrics based on laser Doppler vibrometry: LDV) signals and electrocardiogram: ECG) signals. For both cases, changes in statistics of biometric traits of the same individual is the major challenge which obstructs many methods from producing satisfactory results. We …
-
On the use of mechanical and acoustical excitations for selective heat generation in polymer-bonded energetic materials
… and thermal responses were recorded by scanning laser Doppler vibrometry and infrared thermography, respectively. Direct comparisons between the model and experimental results demonstrated good agreement with the predicted response, with low-order, bulk-scale heating observed along the modal …
-
Theoretical and Experimental Studies of Manipulation of Elastic Waves in Helix Metamaterials
… Wide low-frequency bandgap; Controllable design; Laser vibration measurement; Strong vibration attenuation; Carrera Unified Formulation Abstract Elastic metamaterials exhibit mechanical properties unattainable in natural materials and demonstrate vast potential in vibration and noise reduction, …
-
Microcantilever sensors for biochemical detection and analysis
… to an eight-cantilever array of length 120 μm. Laser doppler vibrometry (LDV) measured the cantilever resonant frequency, which ranged as 218 kHz−5.14 MHz in air and 73 kHz−3.68 MHz in water. The quality factor of the cantilever was 47−151 in air and 18−45 in water. The ability to measure …
Page 1 of 2