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Development And Characterization Of A Directional Radiation Detection System Using A Fuzzy Logic Algorithm, Michael Joseph Willis
Development And Characterization Of A Directional Radiation Detection System Using A Fuzzy Logic Algorithm, Michael Joseph Willis
Doctoral Dissertations
Traditional radiation detection equipment consists of various types of devices that are capable of determining the presence of radioactive sources in the vicinity of the detection unit. Use of these systems typically consists of survey and search methods that employ broad area sweeps to narrow down the location of a radioactive source. Although these methods are effective, they are typically inefficient and lack the ability to produce a directional bearing of the source relative to the measurement location. More efficient methods that provide relative direction information for detected sources would facilitate a more timely response to a potential radiological threat. …
Development Of Tools Needed For Radiation Analysis Of A Cubesat Deployer Using Oltaris, Marycarmen Gonzalez-Dorbecker
Development Of Tools Needed For Radiation Analysis Of A Cubesat Deployer Using Oltaris, Marycarmen Gonzalez-Dorbecker
Master's Theses
Currently, the CubeSat spacecraft is predominantly used for missions at Low- Earth Orbit (LEO). There are various limitations to expanding past that range, one of the major ones being the lack of sufficient radiation shielding on the Poly-Picosatellite Orbital Deployer (P-POD). The P-POD attaches to a launch vehicle transporting a primary spacecraft and takes the CubeSats out into their orbit. As the demand for interplanetary exploration grows, there is an equal increase in interest in sending CubeSats further out past their current regime. In a collaboration with NASA’s Jet Propulsion Laboratory (JPL), students from the Cal Poly CubeSat program worked …
Structural Micrometeoroid And Radiation Shielding For Interplanetary Spacecraft, Jared Allen Ruekberg
Structural Micrometeoroid And Radiation Shielding For Interplanetary Spacecraft, Jared Allen Ruekberg
Master's Theses
This paper focused on two significant space forces that can affect the success of a spacecraft: the radiation and micrometeoroid environments. Both are looked at in the context of the region of space between Earth and Mars. The goal was create reference environments, to provide context to results of environmental modeling, and to provide recommendations to assist in early design decisions of interplanetary spacecraft. The radiation section of this report used NASA's OLTARIS program to generate data for analysis. The area of focus was on the radiation effects for crewed missions, therefore effective dose equivalent was the metric used to …
Characterization Of Mechanically Cooled High Purity Germanium (Hpge) Detectors At Elevated Temperatures, Joseph Benjamin Mccabe
Characterization Of Mechanically Cooled High Purity Germanium (Hpge) Detectors At Elevated Temperatures, Joseph Benjamin Mccabe
Doctoral Dissertations
High resolution gamma spectroscopy is a tool used in nuclear security applications due to its achievable energy resolution and associated ability to identify special nuclear material. This identification ability is achieved by identifying the characteristic gamma-rays of a material. The challenges that have confronted industry concerning the use of hand-held high purity germanium (HPGe) in homeland security applications have centered on weight, geometry, and cool-down time. Typical liquid nitrogen cooled detectors ranging in size from 10% to 150% detectors will cool down sufficiently within 2-6 hours of filling. The cool-down time achieved in this research ranges from 45 min on …
Spectral Radiation Analysis Of Premixed Oxy-Syngas And Oxy-Methane Flames, Naznin Jahan Afrose
Spectral Radiation Analysis Of Premixed Oxy-Syngas And Oxy-Methane Flames, Naznin Jahan Afrose
Open Access Theses & Dissertations
Oxy-fuel combustion has potential to be an impeccable enhancement of current combustion techniques. For a hydrocarbon burning with oxygen the resulting exhaust stream is composed mainly of carbon dioxide and water vapor. This exhaust allows for easier carbon capture and sequestration since the water can be condensed out. Another advantage is the significant reduction of NOx since much of the nitrogen found in air-combustion systems is eliminated. These processes also provide a higher theoretical efficiency which is advantageous. Although beneficial many of the exhaust gas products radiative characteristics are unknown. Motivated by this, this paper focuses on the spectral radiation …
Numerical Study Of Upstream And Downstream Regions Of One Dimensional Detonation Wave In A Dusty Gas Medium, Shubhadeep Banik
Numerical Study Of Upstream And Downstream Regions Of One Dimensional Detonation Wave In A Dusty Gas Medium, Shubhadeep Banik
Masters Theses
"In detonative combustion very high temperatures are attained by the burned gases. As a result, a large amount of thermal energy is produced during the combustion process. This heat can affect the state of the unburned fuel through radiation of heat from the burned gases. In this study a one-dimensional model was deemed appropriate to gain insight into the fundamental structure of the detonation wave. In this model, the detonation wave divides the fluid stream into an upstream region, consisting of fuel and oxidant, and a downstream region, consisting of burned gases. A set of computer programs, some developed during …
An Experimental Method Of Measuring Spectral, Directional Emissivity Of Various Materials And Joule Heating, Robert Bickel
An Experimental Method Of Measuring Spectral, Directional Emissivity Of Various Materials And Joule Heating, Robert Bickel
Theses and Dissertations--Mechanical Engineering
Emissivity is an important parameter in calculating radiative cooling of a surface. In experiments at the NASA Ames hypervelocity ballistic range, one of the main errors indicated in temperature measurements is the uncertainty of emissivity for the materials under investigation. This thesis offers a method for measuring emissivity of materials at elevated temperatures at the University of Kentucky. A test specimen which consists of different sample materials under investigation and a blackbody cavity was heated in a furnace to an isothermal condition at known temperature. The emitted thermal radiation was measured and the comparison of sample and blackbody radiation yielded …
Radiation Heat Transfer In A Particulate Medium Using A Ray Tracing Method, Manish B. Patil
Radiation Heat Transfer In A Particulate Medium Using A Ray Tracing Method, Manish B. Patil
LSU Master's Theses
In the present work, a complete 3D simulation of ray tracing model is developed for studying the radiation heat transfer, associated with laser based additive manufacturing, in both thick and thin particulate beds by using the Monte Carlo method. Additional program is developed for creating different types of packing structures such as simple cubic, rhombohydral and random packing. The scattering mechanisms in the particulate beds for large opaque spheres are evaluated using the specular and diffuse reflection methods. Further, a novel approach has been added to the model to include isotropic, forward and backward scattering mechanisms for a medium which …