Barrett, The Honors College Thesis/Creative Project Collection
Barrett, The Honors College at Arizona State University proudly showcases the work of undergraduate honors students by sharing this collection exclusively with the ASU community.
Barrett accepts high performing, academically engaged undergraduate students and works with them in collaboration with all of the other academic units at Arizona State University. All Barrett students complete a thesis or creative project which is an opportunity to explore an intellectual interest and produce an original piece of scholarly research. The thesis or creative project is supervised and defended in front of a faculty committee. Students are able to engage with professors who are nationally recognized in their fields and committed to working with honors students. Completing a Barrett thesis or creative project is an opportunity for undergraduate honors students to contribute to the ASU academic community in a meaningful way.
Displaying 1 - 10 of 30
Description
Pacemakers in the early 1970s were powered by betavoltaic devices which provided long lasting battery life. The betavoltaic devices also emitted gamma radiation due to inadvertent radioisotope contamination, which could not be completely shielded. The betavoltaic devices were quickly replaced by lithium batteries after their invention, and betavoltaics were abandoned. Modern technological advancements made it possible to isolate beta emitting radioisotopes properly and achieve better energy conversion efficiencies which revived the topic of betavoltaics. This research project has studied state-of-the-art pacemakers and modern radioactive power sources in order to determine if modern pacemakers can be safely nuclear powered and if that is a reasonable combination.
ContributorsAwad, Al-Homam Abdualrahman (Author) / Holbert, Keith (Thesis director) / Aberle, James (Committee member) / Barrett, The Honors College (Contributor) / Electrical Engineering Program (Contributor)
Created2014-12
Description
An introduction to neuroscientific thought aimed at an audience that is not educated in biology. Meant to be readable and easily understood by anyone with a high school education. The first section is completed in its entirety, with outlines for the proposed final sections to be completed over the next few years.
ContributorsNelson, Nicholas Alan (Author) / Olive, M. Foster (Thesis director) / Brewer, Gene (Committee member) / Barrett, The Honors College (Contributor) / Department of Psychology (Contributor) / School of Life Sciences (Contributor) / School of Historical, Philosophical and Religious Studies (Contributor)
Created2014-05
Description
Generally, increasing the electrical size of an antenna will increase the directivity of the antenna. In the case of an array of identical antennas with uniform spacing, the electrical size can be increased by increasing the number of elements. However, directivity can be further increased by performing signal processing on the signals received by elements of an antenna array. This thesis focuses primarily on reproducing and expanding upon a method to increase the directivity of a two-element array using non-linear transmission lines periodically loaded with varactor diodes, which act as harmonic multipliers. Simulation and circuit design is performed using Keysight Advanced Design System, a microwave circuit simulation software package. Furthermore, a hardware implementation is discussed and recommendations are made for construction of the hardware array. Finally, possible expansion of the two-element array to a four or more element array is discussed, and preliminary simulations are examined.
ContributorsHanson, Elliot (Author) / Diaz, Rudolfo (Thesis director) / Aberle, James (Committee member) / Barrett, The Honors College (Contributor) / School of Electrical, Computer, and Energy Engineering (Contributor)
Created2015-05
Description
A hybrid PV/T module was built, consisting of a thermal liquid heating system and a photovoltaic module system that combine in a hybrid format. This report will discuss the work on the project from Fall 2012 to Spring 2013 and the extended section on the economics for the Honors Thesis. Three stages of experiments were completed. Stage 1 showed our project was functional as we were able to verify our panel produced electricity and increased the temperature of water flowing in the system by 0.65°C. Stage 2 testing included “gluing” the flow system to the back of the panel resulting in an average increase of 4.76°C in the temperature of the water in the system. Stage 3 testing included adding insulating foam to the module which resulted in increasing the average temperature of the water in our flow system by 6.95°C. The economic calculations show the expected energy cost savings for Arizona residents.
ContributorsHaines, Brent Robert (Author) / Roedel, Ronald (Thesis director) / Aberle, James (Committee member) / Rauch, Dawson (Committee member) / Barrett, The Honors College (Contributor) / Electrical Engineering Program (Contributor)
Created2013-05
Description
A hybrid PV/T module was built, consisting of a thermal liquid heating system and a photovoltaic module system that combine in a hybrid format. This report will discuss the work on the project from Fall 2012 to Spring 2013. Three stages of experiments were completed. Stage 1 showed our project was functional as we were able to verify our panel produced electricity and increased the temperature of water flowing in the system by 0.65°C. Stage 2 testing included “gluing” the flow system to the back of the panel resulting in an average increase of 4.76°C in the temperature of the water in the system. Stage 3 testing included adding insulating foam to the module which resulted in increasing the average temperature of the water in our flow system by 6.95°C.
ContributorsDenke, Steven Michael (Author) / Roedel, Ron (Thesis director) / Aberle, James (Committee member) / Rauch, Dawson (Committee member) / Barrett, The Honors College (Contributor) / Electrical Engineering Program (Contributor)
Created2013-05
Description
In modern remote sensing, arrays of sensors, such as antennas in radio frequency (RF) systems and microphones in acoustic systems, provide a basis for estimating the direction of arrival of a narrow-band signal at the sensor array. A Uniform linear array (ULA) is the most well-studied array geometry in that its performance characteristics and limitations are well known, especially for signals originating in the far field. In some instances, the geometry of an array may be perturbed by an environmental disturbance that actually changes its nominal geometry; such as, towing an array behind a moving vehicle. Additionally, sparse arrays have become of interest again due to recent work in co-prime arrays. These sparse arrays contain fewer elements than a ULA but maintain the array length. The effects of these alterations to a ULA are of interest. Given this motivation, theoretical and experimental (i.e. via computer simulation) processes are used to determine quantitative and qualitative effects of perturbation and sparsification on standard metrics of array performance. These metrics include: main lobe gain, main lobe width and main lobe to side lobe ratio. Furthermore, in order to ascertain results/conclusions, these effects are juxtaposed with the performance of a ULA. Through the perturbation of each element following the first element drawn from a uniform distribution centered around the nominal position, it was found that both the theoretical mean and sample mean are relatively similar to the beam pattern of the full array. Meanwhile, by using a sparsification method of maintaining all the lags, it was found that this particular method was unnecessary. Simply taking out any three elements while maintaining the length of the array will produce similar results. Some configurations of elements give a better performance based on the metrics of interest in comparison to the ULA. These results demonstrate that a sparsified, perturbed or sparsified and perturbed array can be used in place of a Uniform Linear Array depending on the application.
ContributorsSilbernagel, Drake Oliver (Author) / Cochran, Douglas (Thesis director) / Aberle, James (Committee member) / Electrical Engineering Program (Contributor) / Barrett, The Honors College (Contributor)
Created2016-05
Description
It is a well-established finding in memory research that spacing or distributing information, as opposed to blocking all the information together, results in an enhanced memory of the learned material. Recently, researchers have decided to investigate if this spacing effect is also beneficial in category learning. In a set of experiments, Carvalho & Goldstone (2013), demonstrated that a blocked presentation showed an advantage during learning, but that ultimately, the distributed presentation yielded better performance during a post-learning transfer test. However, we have identified a major methodological issue in this study that we believe contaminates the results in a way that leads to an inflation and misrepresentation of learning levels. The present study aimed to correct this issue and re-examine whether a blocked or distributed presentation enhances the learning and subsequent generalization of categories. We also introduced two shaping variables, category size and distortion level at transfer, in addition to the mode of presentation (blocked versus distributed). Results showed no significant differences of mode of presentation at either the learning or transfer phases, thus supporting our concern about the previous study. Additional findings showed benefits in learning categories with a greater category size, as well as higher classification accuracy of novel stimuli at lower-distortion levels.
ContributorsJacoby, Victoria Leigh (Author) / Homa, Donald (Thesis director) / Brewer, Gene (Committee member) / Davis, Mary (Committee member) / Department of Psychology (Contributor) / Barrett, The Honors College (Contributor)
Created2017-12
Description
Temporal discounting refers to our tendency to discount the value of future rewards. At the extreme, temporal discounting can give rise to detrimental myopic decision-making. Most studies examining the neural basis of temporal discounting in people have been performed using functional Magnetic Resonance Imaging (fMRI). However, fMRI has relatively poor temporal resolution compared with the speed at which people make choices, so understanding choice dynamics using fMRI is difficult. We address the issue utilizing electroencephalography (EEG) to study cortical processes related to temporal discounting. The fMRI literature has found that a network of fronto-parietal brain regions plays an important role during the decision-making process. We aim to explore activity in these regions during the decision process and determine how cortical activity relates to choice parameters. Based on prior fMRI studies, we hypothesized that dorsomedial prefrontal cortex (dmPFC) may act as a regulator of dorsal lateral prefrontal cortex (dlPFC) and there will be an increase in dlPFC activity for more difficult decisions. We also hypothesized that neural activity may be directly related to the temporal discount rate we estimate behaviorally. We utilized regression analysis to determine the relationship. The results found supported our hypotheses. This study may open the door to a better understanding of the dynamic of brain regions while performing a temporal discounting task.
ContributorsTanwisuth, Koranis (Author) / McClure, Samuel (Thesis director) / Brewer, Gene (Committee member) / School of Historical, Philosophical and Religious Studies (Contributor) / School of Mathematical and Statistical Sciences (Contributor) / Department of Psychology (Contributor) / Barrett, The Honors College (Contributor)
Created2017-05
Description
The frontostriatal reward circuit serves an underlying role in reward processing, cognitive planning, and motor control in the context of achieving a goal. Furthermore, research suggests a relationship between the reward circuits and behavior expressed in Attention Deficit Hyperactivity Disorder (ADHD); however, the specific structural differences of the reward circuits in those with ADHD remain ambiguous. Diffusion tensor imaging (DTI) techniques were used to analyze diffusion weighted magnetic resonance imaging (DWI) data in order to examine the structural connectivity of frontostriatal reward pathways in ADHD adolescents compared to typically developing (TD) adolescents. It was hypothesized that measures of impulsivity would be predicted by white matter tract integrity measures in frontostriatal tracts related to affective processing (ventromedial prefrontal cortex to ventral striatum, vmPFC) in adolescents with ADHD, and that there would be reduced tract integrity in tracts related to executive control (dorsolateral prefrontal and anterior cingulate cortex—dlPFC and ACC, respectively). Frontostriatal tracts as well as the hippocampus and amygdala were examined in relation to age and impulsivity using both correlation and regression models. Results indicated that impulsivity declined with age in the TD group while no significant trend was identified for the ADHD group. The hypotheses were not supported and results for both predictions on the affective and executive circuits showed opposite trends from what was expected.
ContributorsHarrison, Sydney Rae (Author) / McClure, Samuel (Thesis director) / Brewer, Gene (Committee member) / Davis, Mary (Committee member) / Department of Psychology (Contributor) / Barrett, The Honors College (Contributor)
Created2017-12
Description
Remotely controlled flying vehicles such as UAVs are becoming more common due to decreases in material costs and increases in performance of components. Radio control link options, however, have not improved at the same rate as airframes, motors, flight controllers, etc [HobbyKing]. Most UAVs require a radio link, often at 2.4 GHz, for flight control, and a second link at 915 MHz for telemetry data transmission [HobbyKing]. Occasionally there is also a video link at either 2.4 GHz or 5.8 GHz. Having multiple transmitters increase power usage from the limited battery reserve that the UAV carries. It also increases weight and space used on the airframe. In addition, the 2.4 GHz band is often congested [ISM Congestion] and does not provide as great a range for a given transmission power as lower frequencies do [Wu]. Attempting to reduce space and weight, power consumption, and simplify design, while increasing control and telemetry range requires the design, testing, and implementation of a radio link that handles both real-time flight control and telemetry with the same transceiver. Only the flight control and telemetry will be addressed in this project. Merging and/or improving the video link will not be tackled at this time in order to simplify project goals to fit inside time constraints. The new radio link system will be verified for functionality then power and range test data will be gathered to determine how effective it is.
ContributorsPortillo-Wightman, Gabrielle Raquel (Author) / Goryll, Michael (Thesis director) / Aberle, James (Committee member) / Electrical Engineering Program (Contributor) / Barrett, The Honors College (Contributor)
Created2017-12