Physical Sciences and Mathematics Commons^™

Setting Constraints On The Lunar Exosphere: A Comprehensive Analysis Of Velocity Resolved Sodium And Potassium Line Profile Measurements, Dona Chathuni P. Kuruppuaratchi

Doctoral Dissertations and Master's Theses

This dissertation outlines and presents the most comprehensive set of velocity-resolved measurements of sodium D2 (5889.9509 Å) lines taken over multiple lunations spanning seven years (2011 – 2017). These data are used to study the morphology and dynamics of the lunar exosphere. Additionally, potassium D1 (7698.9646 Å) is used as a complement to sodium. The two species approach, with sodium being the main attraction, provides constraints on the critical drivers of the lunar exosphere. Observations were made at the National Solar Observatory McMath – Pierce Telescope, Kitt Peak, Arizona where I personally collected both sodium and potassium data over about …

An Exploratory Study Of General Aviation Visual To Instrument Meteorological Condition Contextual Factors, James Harry Hartman Iii

Doctoral Dissertations and Master's Theses

The purpose of this dissertation was to bridge the existing literature gap of outdated contextual factor (CF) research through examination and determination of current General Aviation (GA) Title 14 Code of Federal Regulations (CFR) Part 91 visual flight rules (VFR)-into-instrument meteorological condition (IMC) contextual factors. Contextual factors are a multifaceted arrangement of pertinent events or occurrences contributing to pilot accidents in weather-related decision-making errors. A total of 46 contextual factors were identified and examined from the reviewed research literature. The study examined and determined the presence of the 46 contextual factors, frequencies, and manifestations in the GA VFR-into-IMC Aviation Accident …

An Aviation Weather Preflight Decision Support Tool To Improve Ga Pilots Preflight And Inflight Performance, Jayde M. King

Doctoral Dissertations and Master's Theses

Low hour, inexperienced General Aviation (GA) pilots account for the majority of weather-related incidents, which often result in fatalities. Previous research identifies poor preflight planning practices and a lack of aviation weather knowledge as key contributing factors to the high novice private pilot accident and fatality rate. Research invested into resolving these issues often attempt to introduce new inflight weather technology to assist pilots with weather avoidance. However, these interventions usually result in pilots using the information to strategically navigate closer to degraded weather conditions (Beringer & Ball, 2004; Burgess & Thomas, 2004). Therefore, the purpose of this study was …

Optimization Of Spacecraft Formations About Lagrange Points For The Next Generation Space Weather Prediction Mission, Roberto Cuéllar Rangel

Doctoral Dissertations and Master's Theses

This thesis’s work serves as proof of concept for the Next Generation Space Weather Prediction Mission, a multi-spacecraft mission at various libration points whose objective is to forecast Space Weather hazards with a 12day warning time. This thesis deals with the design and control of orbits of spacecraft formations at different libration points. The systems studied are SunEarth, SunVenus, SunMercury, and SunMars. The orbit design and formation keeping control of the spacecraft are solved simultaneously using an optimization software called DIDO. Initial conditions are obtained through two different strategies. The first one, by placing the spacecraft in a tetrahedral formation …

Python Implementation Of Batch Least-Squares Filter For Satellite Orbit Determination, Austin Ogle

Doctoral Dissertations and Master's Theses

Accurate orbit determination techniques are fundamental to the maintenance and execution of any ongoing space-based mission. This project serves as a guide and demonstration of a batch sequential least-squares filter for Earth-orbiting satellites using exclusively open-source technologies. The target audience for this project was an academic institution aiming to keep track of an irregularly documented satellite. The observation function mimics a telescope, accepting right ascension and declination as measured values.

State propagation was handled using the Poliastro library. This package boasts FORTRANlevel speed by utilizing the DOPRI8 integrator, explicitly calling FORTRAN code. Matrix inversion was solved using the SciPy banded …

Use Of Lidar Data To Investigate The Influence Of Bottom Friction Coefficients For Storm Surge Modeling Of Hurricane Michael In The Florida Panhandle, Sky Comarsh White

Doctoral Dissertations and Master's Theses

Current storm surge modeling typically uses local land use land cover (LULC) maps coupled with lookup tables to parameterize surface roughness because the process is defensible and easily automated at the regional scale. However, this is not a truly accurate method since LULC data is generalized for an area and often contains misclassifications. Intra-class variability is also a concern as variations in obstacle density within LULC classifications are prominent at typical storm surge model resolution scales ranging from 20-meters to 200-meters in the floodplain. Using lidar data, topography and the 3-dimensional structure of above-ground obstructions can be more accurately characterized, …

Neusch Automated Filter System: A Custom-Designed Photo-Filter Switching Apparatus For Embry-Riddle’S 1 Meter Telescope, Tyler Neusch

Doctoral Dissertations and Master's Theses

The one-meter telescope on the roof of Embry-Riddle’s College of Arts and Sciences building in Daytona Beach, FL is an advanced piece of technology supporting education and public outreach. One part of this telescopic system is a custom-made Cassegrain Instrument Mount. This one-of-a-kind mount allows for multiple scientific instruments to be simultaneously mounted to the telescope. However, its mechanical layout prevents the use of a traditional device known as a filter wheel.

Filter wheels store multiple photo-filters each capable of filtering out all but certain wavelengths of light for use with a CCD camera. Therefore, a filter wheel allows the …

Assessing If Motivation Impacts General Aviation Pilots’ Persistence In Varying Weather Conditions, Sabrina Woods

Doctoral Dissertations and Master's Theses

Continued flight under visual flight rules into instrument meteorological conditions is the predominant cause for fatal accidents by percentage, for general aviation aircraft operations. It is possible that a pilot’s motivation or reason for flying will override other safer, more logical courses of action when a hazard presents itself. The decision appears to stem from a willingness to persist in a course of action despite factors that indicate an alternate and safer course is warranted. This research addresses what is currently presumed about the decision to continue flying under visual flight rules into instrument conditions and marries those ideas with …

Atmospheric And Ionospheric Responses To Acoustic And Gravity Waves Driven By Earthquakes And Tsunamis, Pavel A. Inchin

Doctoral Dissertations and Master's Theses

Natural hazards (NHs) are causes for significant concern due to their potentially catastrophic impacts on society. The study of their effects on the upper atmosphere can provide significant insight into the coupled nature of geophysical processes, and drives important applications for radio communication and navigation, leading potentially to the development of NH early-warning systems. Although general concepts underlying their coupling mechanisms are well understood, recent computational capabilities, supported by high temporal and spatial density of observations, have reached the level where such processes can be modeled with unprecedented realism for detailed case studies. The studies provided in this thesis are …