Open Access. Powered by Scholars. Published by Universities.®
Articles 1 - 4 of 4
Full-Text Articles in Entire DC Network
Simulation And Phases Of Macroscopic Particles In Vortex Flow, Heath Eric Rice
Simulation And Phases Of Macroscopic Particles In Vortex Flow, Heath Eric Rice
Electronic Theses and Dissertations
Granular materials are an interesting class of media in that they exhibit many disparate characteristics depending on conditions. The same set of particles may behave like a solid, liquid, gas, something in-between, or something completely unique depending on the conditions. Practically speaking, granular materials are used in many aspects of manufacturing, therefore any new information gleaned about them may help refine these techniques. For example, learning of a possible instability may help avoid it in practical application, saving machinery, money, and even personnel. To that end, we intend to simulate a granular medium under tornado-like vortex airflow by varying particle …
Multidoman Piezo-Ceramic Cantilever, David Paul Sedorook
Multidoman Piezo-Ceramic Cantilever, David Paul Sedorook
Electronic Theses and Dissertations
PZT-5H is a ferroelectric and piezoelectric material that has many applications that are the subjects of current research. As a ferroelectric, PZT-5H has a permanent electrical polarization that arises from ferroelectric domains. In this thesis, numerical simulations were conducted via the well know Finite Element Method of several types of piezoelectric cantilevers that were made of PIC-181, a high quality PZT-5H made in Germany. Single crystal cantilever models with multiple polarization vectors were investigated with Q factors ranging from Q = 50 to Q = 1200, where the acoustical displacements were calculated. Further, the displacements were calculated for a multidomain …
Horizons, Holography And Hydrodynamics, Arif Mohd
Horizons, Holography And Hydrodynamics, Arif Mohd
Electronic Theses and Dissertations
In this dissertation we study black-hole horizons in general relativity and in Gauss-Bonnet gravity. We generalize Wald's "black-hole entropy is the Noether charge" construction to the first-order formalism of these theories. Next we construct the "membrane paradigm" for black objects in Gauss-Bonnet gravity and demonstrate how the horizon can be vieas a membrane with fluidlike properties. Holography is invoked to relate the transport coefficients obtained for the horizons in the membrane paradigm with the transport coefficients which describe the hydrodynamic limit of the boundary gauge theory.
Standoff Laser Interferometric Photoacoustic Spectroscopy For The Detection Of Explosives, Logan Marcus
Standoff Laser Interferometric Photoacoustic Spectroscopy For The Detection Of Explosives, Logan Marcus
Electronic Theses and Dissertations
There will unfortunately always be a pressing need to detect and identify explosive materials. Performing detection at a standoff distance is much safer and this is the impetus for this work. Photoacoustic spectroscopy is well suited to the task of explosive detection at a standoff distance. A detailed theory of the standoff measurement of the physical response of a system to photoacoustic excitation with an interferometric sensor has been constructed and tested. The use of this methodology to measure the standoff photoacoustic spectrum of TNT with an interferometric sensor has clearly been demonstrated. This methodology and the tested theory can …