Electronic Theses and Dissertations http://hdl.handle.net/1957/89 2016-06-28T02:41:06Z 2016-06-28T02:41:06Z Moving Towards Academic Success and Life Long Learning Becker, Derek Raymond http://hdl.handle.net/1957/59362 2016-06-27T20:03:10Z 2016-06-17T00:00:00Z Moving Towards Academic Success and Life Long Learning Becker, Derek Raymond Early learning skills, such as executive function (EF), are a key component of healthy development and predict long-term academic success. Yet many children are entering kindergarten without the necessary skills (including EF) that are needed to set them on a successful learning trajectory. Early prekindergarten classrooms that encourage a high quality learning environment have shown a positive impact on the development of EF. However, because learning also takes place outside the classroom through fine and gross motor play, there is also a need to better understand the role of the physical body in the learning process. To address this gap, this dissertation focused on visual motor skills (VMS), and sport participation as tools that could be used to promote school readiness and long term academic success. Study I examined direct and interactive effects among different aspects of EF (working memory, cognitive flexibility, inhibitory control) and VMS with math and literacy achievement at four time points between the prekindergarten and kindergarten year. At the fall of prekindergarten, a behavioral measure of EF, working memory, and inhibitory control were directly associated with math. In addition, children’s VMS, working memory and cognitive flexibility were associated with initial literacy scores. Growth in math between the fall and spring of prekindergarten was predicted by VMS, a behavioral measure of EF, and a measure of cognitive flexibility, with working memory predicting growth between the spring of prekindergarten and the fall of kindergarten. For literacy, measures of VMS, working memory, and cognitive flexibility in the fall of prekindergarten predicted growth in literacy during the spring. In addition, at two transitional points, during the fall of prekindergarten and kindergarten, VMS compensated for low cognitive flexibility and behavioral EF on initial math achievement (fall), and for growth in math between the spring of prekindergarten and fall of kindergarten, respectively. For Study II, 15 youth sports (e.g., soccer, basketball, swimming, running) were categorized by being either open- or closed-skilled and by intensity to assess if children who play open-skilled sports, metabolically intense sports, or both, have higher EF, literacy, and math scores. The interaction between open-skilled sports and intensity was also explored with EF, literacy, and math. Results showed the relationship between sport intensity and EF varied by the number of open-skilled sports, with sport intensity more related to EF for children who play fewer open-skilled sports and less related for children who played a greater number of open-skilled sports. For math, results differed for open-skilled and intense sports, with intensity associated with lower math scores, and open-skilled sports associated with higher math scores. Together, these studies offer a unique view into the role of the physical body and movement in the learning process, and could inform interventions aimed at promoting and maintaining EF and academic achievement prior to, and after entering formal school. Graduation date: 2017 2016-06-17T00:00:00Z Regional Scale Modeling of Climate, Cryosphere, and Freshwater Discharge in Changing Coastal Mountain Environments Beamer, Jordan P. http://hdl.handle.net/1957/59360 2016-06-27T19:52:45Z 2016-06-02T00:00:00Z Regional Scale Modeling of Climate, Cryosphere, and Freshwater Discharge in Changing Coastal Mountain Environments Beamer, Jordan P. The glaciated coastal mountain watersheds that drain into the Gulf of Alaska (GOA) provide a model laboratory to explore the challenges of hydrological modeling and study the impact of climate and glacier cover change on regional hydrology. The region is data-sparse and contains a complex assemblage of topography and land cover, including a system of mountain glaciers that are retreating at some of the highest rates on Earth. The high rates of runoff from precipitation and glacial melt delivered by coastal rivers influence ocean circulation patterns, rates of global sea level rise, and provide spawning habitat for the large salmon populations. Physically-based hydrological modeling of the major water budget components of the GOA, driven using historical reanalysis weather data and land cover, reveals that the modeled water budget components, particularly precipitation input, vary widely between commonly-used weather products. The majority of the large freshwater flux into the GOA is derived from distributed coastal streams rather than the large inland rivers. The modeled seasonal aggregated GOA hydrograph is dominated by the spring and early summer snowmelt, and supplemented by late summer glacial ice melt. Model results demonstrate good agreement with NASA Gravity Recovery and Climate Experiment (GRACE) satellite data in terms of annual amplitudes and long term losses (ice loss), and suggest that existing GRACE solutions, previously reported to represent glacier mass balance alone, are actually measuring the full water budget of land and ice surfaces. An ensemble of climate models and future emissions scenarios were paired with systematically altered land cover to test the sensitivity of the hydrologic system to changes in regional climate patterns and glacier coverage representative of late twenty first century conditions. Compared with the hindcast simulations, the model results forced with increased regional air temperatures and precipitation inputs and reduced glacier cover produce an increase in the annual GOA freshwater discharge volume. The seasonal GOA hydrograph is flattened due to increased winter runoff from more winter rainfall and less snow accumulation, and lower levels of snowmelt and glacier ice contribution. Large uncertainties exist in the direction of change in the glacier runoff component, primarily due to uncertainties that exist in predicting glacier response to climate change. Hydrological modeling with high resolution and inclusion of relevant physical processes can produce significantly improved products that are of high value to and in demand by numerous other scientific communities. However, the value and accuracy of the output from the hydrologic model is highly dependent on the weather forcing quality. Given the considerable importance of quality weather forcing for hydrologic modeling, it is imperative to assess the suitability of multiple products by evaluating local and regional performance and accounting for uncertainty. Additional efforts should be made to improve the spatial resolution of the reanalysis through downscaling and to strategically increase the number of weather stations at high elevations and incorporate that data into weather forcing datasets. Graduation date: 2017 2016-06-02T00:00:00Z Application of Self-Assembled Monolayers to InGaZnO Thin Film Transistors Motley, Joshua R. http://hdl.handle.net/1957/59359 2016-06-27T17:56:13Z 2016-05-27T00:00:00Z Application of Self-Assembled Monolayers to InGaZnO Thin Film Transistors Motley, Joshua R. Investigations on the application of self-assembled monolayers (SAM) to indium gallium zinc oxide (IGZO) thin film transistors (TFT) for fabrication and channel modification are presented. The back channel of IGZO thin film transistors can be modified by the absorption of self-assembled monolayers. The electrical properties of the IGZO exposed back channel are sensitive to surface chemistries and can be tailored using SAMs. Chemistry at the back channel interface alters device performance. The back channel surface sensitivities can be used in applications for chemical sensing TFTs. IGZO TFTs with and without octadecyl phosphonic acid applied to the back channel with varied channel thicknesses (10-50 nm) were examined. TFT parameters, such as, turn-on voltage, hysteresis, mobility, subthreshold swing, and current on/off ratio were evaluated by current-voltage electrical measurements. The use of electrohydrodynamic ink jet (EHDP) printing as non-contact method for patterning etch resists with sub-10 μm features was demonstrated for fabrication of IGZO TFTs. EHDP uses an electric field to generate ink droplets that can be smaller than the nozzle diameter. EHDP was used for depositing a self-assembled monolayer, n-hexyl phosphonic acid (HPA), and photoresist, SU8, as etch resists for patterning the IGZO TFT channel. Drop on demand printing is accomplished by overlapping of discrete droplets to form the desired feature. The optimal ink formulations and EHDP parameters were determined for each ink. Parameters were optimized for producing the smallest, uniform printed features. Bottom gate IGZO TFTs were fabricated by plasma sputtering IGZO onto a SiO₂/Si substrate. The IGZO TFT channels were patterned by printing HPA or SU8 ink as the etch resist, and using HCl as the etch solution. Indium tin oxide source and drain were deposited over the patterned channel using plasma sputtering. The electrical performance of IGZO TFTs patterned using HPA and SU8 were compared and evaluated using I-V electrical measurements. Drop on demand printing offers a high-speed, low cost route to TFT fabrication and manufacturing. The long narrow channels produced have applications for TFT sensor technologies. EHDP was shown to be capable of printing etch resists for the patterning and fabrication of IGZO TFTs on the scales relevant for digital displays. Graduation date: 2017 2016-05-27T00:00:00Z Design and Development of a Salticid Inspired Jumping Robot Tachella, Ramsey http://hdl.handle.net/1957/59358 2016-06-27T17:46:58Z 2016-05-11T00:00:00Z Design and Development of a Salticid Inspired Jumping Robot Tachella, Ramsey The ability to jump allows small robots to traverse rough terrain, clear large obstacles, and quickly reach elevated locations. These abilities have applications in a variety of areas such as, search and rescue, environmental monitoring, and urban warfare. The primary focus in current state-of-the-art jumping robots has been on jumping as high or far as possible, with little focus on how to change the prelaunch dynamics to accomplish different trajectories. This lack of variety limits the utility of jumping robots by reducing their effective workspace. To solve this problem, we explored the jumping behavior of the Salticid family of jumping spiders. Salticid spiders are able to change their leg geometry and use their front legs to channel jump energy into a vaulting motion. Vaulting allows the spider to achieve alter trajectories than are possible by extension of the rear legs alone. We mapped the spiders jumping mechanism onto a four-bar linkage to develop a model for the spiders jumping mechanics.This model is then used to develop a robot that is able to effectively mimic the spider's jumping behavior. Graduation date: 2017 2016-05-11T00:00:00Z