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Full-Text Articles in Engineering
Cloud-Induced Uncertainty For Visual Navigation, Alyssa N. Gutierrez
Cloud-Induced Uncertainty For Visual Navigation, Alyssa N. Gutierrez
Theses and Dissertations
This research addresses the numerical distortion of features due to the presence of clouds in an image. The research aims to quantify the probability of a mismatch between two features in a single image, which will describe the likelihood that a visual navigation system incorrectly tracks a feature throughout an image sequence, leading to position miscalculations. First, an algorithm is developed for calculating transparency of clouds in images at the pixel level. The algorithm determines transparency based on the distance between each pixel color and the average pixel color of the clouds. The algorithm is used to create a dataset …
Gps Multipath Reduction With Correlator Beamforming, Jason M. Barhorst
Gps Multipath Reduction With Correlator Beamforming, Jason M. Barhorst
Theses and Dissertations
This research effort investigates the feasibility of beamforming using a single Global Positioning System (GPS) front end. Traditional methods of beamforming use multiple front ends, typically one per antenna element. By enabling a receiver to sample a switched antenna array, the hardware cost of implementing a GPS antenna array can be significantly reduced. Similar techniques of reducing the number of receivers have been used by Locata Corporation in the design of their non-GPS positioning systems. However, Locata Corporation's local transmitters provide a signal strength much higher than GPS's signal strength. For this reason, the inclusion of low-noise amplifiers into the …
Selectively Tuning A Buckled Si/Sio2 Membrane Mems Through Joule Heating Actuation And Mechanical Restriction, Kyle K. Ziegler
Selectively Tuning A Buckled Si/Sio2 Membrane Mems Through Joule Heating Actuation And Mechanical Restriction, Kyle K. Ziegler
Theses and Dissertations
This research followed previous work and attempted to modify the spring in two ways. First, a Ti/Au meander resistor was deposited atop the membrane in an effort to actuate the membrane and change the spring constant. Secondly, a series of overhanging cantilevers were attached to the bulk substrate surrounding the membrane in an effort to constrain the membrane buckling deflection to the negative stiffness region. Membrane buckling was investigated through Finite Element analysis (FEA) and analytical equations. Deflections were measured using an interferometric microscope (IFM) and force/deflection measurements were captured using a unique measurement scheme. The results concluded that by …