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Full-Text Articles in Engineering
Design Of An Offner-Chrisp Imaging Spectrometer For A Planetary Fluorescence Instrument, Tristan Wells Carlson
Design Of An Offner-Chrisp Imaging Spectrometer For A Planetary Fluorescence Instrument, Tristan Wells Carlson
McKelvey School of Engineering Theses & Dissertations
Spectrometers have been an integral part of space exploration in the late 20th and 21st centuries and will continue to provide quantitative measurements to answer exciting questions like, “Is or was there life on other planets?” PERISCOPE, Probe for Exploring Regolith and Ice by Subsurface Classification of Organics, Polycyclic aromatic hydrocarbons, and Elements, is a next generation spectrometer designed to explore icy worlds like Europa. It uses time-resolved ultraviolet (UV) fluorescence spectroscopy, a technique that identifies organic molecules, polycyclic aromatic hydrocarbons (PAH), and rare earth elements (REE). Photon wavelength discrimination is very important for this technique and is accomplished by …
Three Dimensional Photonics Structures: Design And Applications, Mansoor Sultan
Three Dimensional Photonics Structures: Design And Applications, Mansoor Sultan
Theses and Dissertations--Electrical and Computer Engineering
Photonics is an emerging technology for light control, emission, and detection. Photonic devices control photons the same way electronic circuits control electrons in active or passive mode depending on the energy requirement of the device. This dissertation will discuss the design, fabrication, testing of photonic structures with applications including imaging and renewable energy. First, we developed a novel lithography method for fluoropolymer resist based on variable pressure electron beam lithography (VP-EBL). VP-EBL proves to be an efficient method for patterning a widely used, but challenging to process, fluoropolymer, Teflon AF. However, rather than solely mitigating charging, the ambient gas is …
Saturation Behaviors In Deep Turbulence, Jeffrey R. R. Beck
Saturation Behaviors In Deep Turbulence, Jeffrey R. R. Beck
Dissertations, Master's Theses and Master's Reports
Distributed-volume atmospheric turbulence near the ground significantly limits the performance of incoherent imaging and coherent beam projection systems operating over long horizontal paths. Defense, military and civilian surveillance, border security, and target identification systems are interested in terrestrial imaging and beam projection over very long horizontal paths, but atmospheric turbulence can blur the imagery and aberrate the laser beam such that they are beyond usefulness. While many post-processing and adaptive optics techniques have been developed to mitigate the effects of turbulence, many of these techniques do not work as expected in stronger volumetric turbulence, or in many cases don't work …
Microwave Detection Of Surface Breaking Cracks In Metallic Structures Under Heavy Corrosion And Paint, John Robert Gallion
Microwave Detection Of Surface Breaking Cracks In Metallic Structures Under Heavy Corrosion And Paint, John Robert Gallion
Masters Theses
"We live in the world of "aging infrastructures". In this environment, critical and heavily utilized infrastructure, i.e. ships, planes, bridges, etc., are operating at or beyond their designed age. Replacement is no longer an option and "retirement for cause" is the current approach to maintenance and replacement. Consequently, there is an ever-increasing demand for efficient and robust nondestructive evaluation (NDE) methods that can determine the physical health of these structures. Large structures, which are primarily made of metals, either steel or aluminum, are susceptible to high-stress cracking and corrosion. Stress-induced cracks in heavily corroded steel, used in bridges, railroads, storage …
Enhancing The Resolution Of Imaging Systems By Spatial Spectrum Manipulation, Wyatt Adams
Enhancing The Resolution Of Imaging Systems By Spatial Spectrum Manipulation, Wyatt Adams
Dissertations, Master's Theses and Master's Reports
Much research effort has been spent in the 21st century on superresolution imaging techniques, methods which can beat the diffraction limit. Subwavelength composite structures called ``metamaterials" had initially shown great promise in superresolution imaging applications in the early 2000s, owing to their potential for nearly arbitrary capabilities in controlling light. However, for optical frequencies they are often plagued by absorption and scattering losses which can decay or destroy their interesting properties. Similar issues limit the application of other superresolution devices operating as effective media, or metal films that can transfer waves with large momentum by supporting surface plasmon polaritons. In …
A Compact Ultra Wide-Band Radar System For See-Through-Wall Applications, Stephen G. Magoon
A Compact Ultra Wide-Band Radar System For See-Through-Wall Applications, Stephen G. Magoon
Masters Theses
A compact Ultra wide-band (UWB) radar system for through-wall applications has been developed. Lightweight, portable and low in power consumption, it is configurable for both bistatic and monostatic operation. It uses low cost, off-the-shelf surface mount components, and is ideally suited for ranging, 3d-imaging, and wall characterization. Tests show excellent pulse width generation, resulting in very broadband transmission (0.7 – 5.6 GHz) and good receiver dynamic range, resulting in accurate measurement capabilities.