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 39 for “"mechanical vibrations"”.
-
Magnetic induction systems to harvest energy from mechanical vibrations
… induction systems to harvest energy from mechanical vibrations. Two styles of magnetic induction systems - magnet-through-coil and magnet-across-coils - were analyzed. MATLAB models were created to serve as a design aid and optimization tool for both styles of magnetic induction systems. …
-
Synthesis of electric networks interconnecting PZT actuators to efficiently damp mechanical vibrations
… thesis is to show that it is possible to damp mechanical vibrations in a given frame, constituted by Euler beam governed by the equations of an elastica, by means of piezoelectric actuators glued on every beam and interconnected each other via electrical networks.Since we believe that the most …
-
Impact of vibration-induced disturbances on superconducting magnets
… discrete ground coils causes electromagnetic and mechanical vibrations. These disturbances limit the performance of the maglev, as occurred in the Japanese MLU002 maglev. Here I examine how the electromagnetic oscillations are translated into mechanical vibrations and the subsequent effects on …
-
Remote optical excitation and sensing of structural vibration
… non-contact techniques for optical excitation of mechanical vibrations in structures and with the use of non-contact fibre optic interferometers for the measurement of parameters which characterise these mechanical vibrations. Taken together, the excitation and sensing systems provide a method for …
-
Modal analysis of laser vibrated structures
… irradiation of metallic structures to excite mechanical vibrations within those structures. As found by other authors, single high-power laser pulses ablate the irradiated surface material and may impulsively excite structural vibration; however, the use of laser power densities above the …
-
Toward a demonstration of a Light Force Accelerometer
… was prohibitively difficult due to destabilizing mechanical vibrations. For a microsphere in atmospheric pressure, the estimated bias stability was 318 jig after 300 seconds of averaging, and the approximate short-term sensitivity was 500 pg/v/ Hz. Stabilization of mechanical vibrations and …
-
Review of energy harvesting methods for twin screw extruders
… harvesting technologies typically utilize either mechanical, thermal, radiation, flow-based, or bio-chemical energy sources. Research in low-power energy harvesting technologies is motivated by an increased interest in the Internet of Things and the need to create isolated electronic systems, such …
-
Energy harvesting of random wide-band vibrations with applications to an electro-magnetic rotational energy harvester
… of ambient vibration by transduction of mechanical kinetic energy into electrical energy. Many mechanical or electro-mechanical systems produce mechanical vibrations. The kinetic energy associated with these mechanical vibrations represents a potential source of energy for sensors and …
-
Structural magnetic induction dampers in buildings
… magnetic induction dampers for dampening mechanical vibrations in buildings subjected to strong dynamic excitations. The concept of energy harvesting in various fields of engineering is first examined. Then it is applied to the design of magnetic induction dampers in buildings. Various …
-
Advances in Magnetic Resonance Phase‐Contrast Velocity Mapping
… magnetic field monitoring demonstrating that mechanical vibrations can have a large impact on flow quantification. Approaches for background phase offset correction based on field monitoring data are discussed. To address the long scan times, dual slice excitation and spatiotemporally …
-
A new degenerate Fermi gas apparatus
… is designed to eliminate noise generated by the mechanical vibrations of the machine. The system relies on taking multiple images with time scale shorter than typical vibration periods. Third, a new experiment control system is developed. The new control system replaced the outdated 8 years old …
-
Phonon-polaritons in bulk and patterned materials
… are admixtures of coupled electromagnetic and mechanical vibrations in polar crystals. An in-depth theoretical treatment supplemented with simulations of experimental results of a four-wave mixing impulsive stimulated Raman scattering (ISRS) method to generate and probe polaritons with …
-
Penetration force measurements in the central nervous system with silicon electrodes
… is to reduce the penetration force by using mechanical vibrations. First, the penetration force was measured in the rat brain. To measure the penetration force, the microelectrode was connected to a load transducer. Because dura is a tough membrane to penetrate, it is usually removed during …
-
Characterization of modified polyimide adhesives
… The response of this metal/polymer composite to mechanical vibrations and the passage of electric current was measured. Model aluminum conductor bar joints containing this material were assembled and exposed to elevated temperatures for extended periods of time while the electrical properties of …
-
Computational Modeling of Geometry Dependent Phonon Transport in Silicon Nanostructures
… boundary geometry. Phonons are quantized mechanical vibrations that are the dominant carrier of heat in semiconductor materials and their aggregate behavior determine a nanostructure's thermal performance. Phonon-geometry scattering processes as well as waveguiding effects which result …
-
Electromechanical Coupling of Distributed Piezoelectric Transducers for Passive Damping of Structural Vibrations: Comparison of Network Configurations
… wave guides to obtain an optimal electro-mechanical energy exchange and therefore to dissipate the mechanical vibrational energy in the electric form. Modular PiezoElectroMechanical (PEM) structures are constituted by continuous elastic beams (or bars) coupled, by means of an array of PZT …
-
Optical resistance of dielectric coatings to multi-pulse femtosecond laser radiation /
… laser beam propagation direction, energy or even mechanical vibrations in the optical systems produce apparently accumulative damage statistics. The exposed area increases shot-by-shot, thus increasing the S-on-1 probability of damage.
-
Dynamics of vacuum-sealed, double-leaf partitions
… where the acoustics of the inner chamber and mechanical vibrations of structural supports are passively and actively controlled. The work presented here is unique in that the proposed system aims to eliminate the need for active acoustic control of transmitted acoustic energy by removing all …
-
Wide stripe single and dual wavelength mode semiconductor diode lasers
… drawbacks in that they are very sensitive to mechanical vibrations. This work has focused on the use of an internal grating, a distributed Bragg reflector (DBR) grating that was monolithically inserted into the gain section of a semiconductor laser. The result is a single wavelength mode …
-
Surface micromachined MEMS variable capacitor with two-cavity for energy harvesting
… the wasted energy associated with undesirable mechanical vibrations to power microelectronic sensors and actuators widely found in structures and systems surrounding us. The harvested power, though very small, can have a profound effect on the usage of microsensors. First, the self-powered …
Page 1 of 2