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Full-Text Articles in Engineering
Interim Access To The International Space Station, Tyson Karl Smith
Interim Access To The International Space Station, Tyson Karl Smith
All Graduate Theses and Dissertations, Spring 1920 to Summer 2023
This thesis evaluates mission scenarios using the existing Evolved Expendable Launch Vehicles for delivering the Crew Exploration Vehicle to the International Space Station. The Space Shuttle is scheduled to retire in the year 2011 and the Ares I is being developed to replace it. With its current schedule, the earliest that the Ares I will become fully operational is 2016. The configurations in this thesis are presented to narrow the gap in which the USA does not have direct access to the International Space Station. They also present "buy down" options for the USA human space operations, if the current …
Uncertainty Analysis For Land Surface Model Predictions: Application To The Simple Biosphere 3 And Noah Models At Tropical And Semiarid Locations, Joshua K. Roundy
Uncertainty Analysis For Land Surface Model Predictions: Application To The Simple Biosphere 3 And Noah Models At Tropical And Semiarid Locations, Joshua K. Roundy
All Graduate Theses and Dissertations, Spring 1920 to Summer 2023
Uncertainty in model predictions is associated with data, parameters, and model structure. The estimation of these contributions to uncertainty is a critical issue in hydrology. Using a variety of single and multiple criterion methods for sensitivity analysis and inverse modeling, the behaviors of two state-of-the-art land surface models, the Simple Biosphere Model 3 and Noah model, are analyzed. The different algorithms used for sensitivity and inverse modeling are analyzed and compared along with the performance of the land surface models. Generalized sensitivity and variance methods are used for the sensitivity analysis, including the Multi-Objective Generalized Sensitivity Analysis, the Extended Fourier …
Meshed Patch Antennas Integrated On Solar Cell - A Feasibility Study And Optimization, Timothy W. Turpin
Meshed Patch Antennas Integrated On Solar Cell - A Feasibility Study And Optimization, Timothy W. Turpin
All Graduate Theses and Dissertations, Spring 1920 to Summer 2023
This thesis work presents the feasibility of integrating meshed patch antennas directly onto the solar cell assembly to save valuable surface real estate of a small satellite. The solar cell cover glass is used as the substrate for the patch antenna. The antenna topology is chosen to be a meshed patch so that it is transparent to light to ensure the proper operation of solar cells. We found that although there is a compromise between the antenna efficiency and see-through percentage, one is able to optimize the antenna by carefully designing the mesh. To verify the design and integration, a …