Open Research Oklahoma (Oklahoma State Univ.)
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Wheat grazeout versus harvest for grain
No full textThe Oklahoma Cooperative Extension Service periodically issues revisions to its publications. The most current edition is made available. For access to an earlier edition, if available for this title, please contact the Oklahoma State University Library Archives by email at [email protected] or by phone at 405-744-6311
Wind estimation using quadcopters
No full textWind estimation techniques for unmanned aerial vehicles (UAVs) have the potential to improve navigation and flight performance of vehicles, and support environmental studies and meteorology. Compared to wind estimation using fixed-wing UAVs, rotary UAVs can estimate wind at one point in space as well as vertical wind profiles. In this dissertation, wefirst consider a nonlinear estimation problem where a quadcopter hovers or moves in a wind field. We show that the quadcopter dynamics with the nominal thrust model and quadratic drag model is invariant and the measurement equation is equivariant under actions of the SE(3) Lie group. We design an Invariant Extended Kalman Filter (IEKF) by taking advantage of the invariance in the system dynamics. Second, we establish invariance properties of various thrust and drag models, and incorporate them in the IEKF design. The resulting design is successfully validated in simulations. Through Monte-Carlo simulations, we demonstrate that IEKF shows an improvement in transient performance over a conventional Extended Kalman Filter (EKF) and IEKFs with accurate thrust models improve the state and wind estimation. Third, we perform both indoor and outdoor experiments and validate the effectiveness of IEKFs. Fourth, we consider spatial-temporal wind field estimation using multiple quadcopters. For wind state fusion, we develop a sequential covariance intersection (SCI) method and a sequential weighted exponential product (SWEP) method which can fuse wind state as well as covariance under unknown correlations. The effectiveness of the designed partial state fusion methods is verified in simulations. We further identify the invariance in a Gaussian-basis function wind model and design an IEKF with the Gaussian basis (IEKF-GB). The simulation results show the superiority of IEKF-GB under various spatial and temporal wind fields
Impact of child nutrition programs offered in schools on daily nutrition and dietary quality
No full textThe Oklahoma Cooperative Extension Service periodically issues revisions to its publications. The most current edition is made available. For access to an earlier edition, if available for this title, please contact the Oklahoma State University Library Archives by email at [email protected] or by phone at 405-744-6311
Productivity and economic viability of hybrid sweetgum in Oklahoma, Texas, and Louisiana
No full textThe pulp and paper industry of the south-central U.S., which relies partly on hardwood timber, has faced supply chain issues due to excessive hardwood mortality, harvesting/transportation challenges, and heightened demand from the oil and gas industries. Moreover, demand for wood-based renewable energy is increasing. One solution is to utilize highly-productive and site-tolerant species to generate timber, pulp, and biofuel feedstock in a plantation setting. While sweetgum (Liquidambar styraciflua) is a potential hardwood candidate, research suggests hybrid sweetgum (Liquidambar formosana x styraciflua) exhibits greater productivity under highly-controlled conditions. My study, spanning southeastern Oklahoma, northeastern Texas, and northwestern Louisiana explored this at an operational scale. Thirty-five stands were sampled, eleven with half-sib families of sweetgum and 24 with hybrid clones. Stand ages ranged from 6-11 years for half-sibs and 5-8 years for hybrids. Site conditions varied greatly, but planting densities and management intensities were relatively similar. Hybrids had greater wood specific gravity (0.49 vs 0.46 g/cm3) and stem bulk density (0.94 vs 0.87 Mg/m3). Decreased stem taper also meant the hybrids were much heavier for a given stem diameter. Ultimately, hybrids exhibited significantly faster growth than the half-sibs at the same age (15.8 vs 11.4 Mg/hectare/y). From an economic standpoint, this increased growth rate allowed the hybrids to excel, despite the higher cost of seedlings. The hybrids produced significantly better economic returns than the half-sibs under every management scenario and market scenario tested. For example, the half-sib stands produced a mean LEV of -932.20/ha. In conclusion, my study confirms hybrid sweetgum’s viability by demonstrating its superior productivity and greater economic returns
Development and psychometric properties of a new measure of stigma experienced by light and non-drinking college students
No full textIntroduction: The number of college students who rarely or never consume alcohol in the United States is growing. However, past research has found that college students can be stigmatized for light or non-drinking behaviors. While previous research has examined experiences of enacted, perceived, and self-stigma among light and non-drinking college students qualitatively, few quantitative studies exist. As such, the purpose of the present study was to create a self-report measure that assessed experiences of enacted, perceived, and self-stigma among light and non-drinking college students.Method: First, three participants participated in a pilot group discussion evaluating the 58 potential scale items. Pilot group participants provided feedback on how easily understood the items were as well as the wording and phrasing of items. Then, participants from two separate samples of undergraduate students (N = 495 for the exploratory factor analysis sample, N = 256 for the confirmatory factor analysis sample) from a large, Midwestern university participated in the present study. Participants completed online questionnaires related to drinks consumed per week, drinking attitudes, self-concealment, and perceived social support. Participants in the first sample also completed the original 58 scale items. An exploratory factor analysis was then used to narrow down the scale items and participants in the second sample completed the 18 retained scale items. Finally, participants in the second sample completed the scale again four weeks later to assess test-retest reliability.Results: The exploratory factor analysis revealed a four-factor structure fit the data best and accounted for 44.03% of the variance. The confirmatory factor analysis then revealed the four-factor model provided an adequate fit for the data. Discussion: The current study created a measure called the College Alcohol Stigma Scale which may serve as a valuable tool to better understand experiences of enacted, anticipated, and self-stigma as well as values engagement among college students who engage in light drinking or who abstain from drinking. Future research should assess how this scale predicts drinking outcomes and intentions to abstain from future alcohol use
Tax implications of CEO compensation packages
No full textThis study examines associations between different forms of CEO compensation and corporate tax avoidance activity. I develop a new theoretical framework for predicting the associations between CEO compensation and corporate tax avoidance. I also rank forms of compensation by their impact on various forms of tax avoidance ranging from conservative to aggressive approaches. This assists corporate boards by providing information on which forms of tax avoidance are associated with various compensation schemes. That is, the results inform corporate boards about potential tax consequences of implementing certain compensation packages
Reliability and usability of ChatGPT for library metadata
No full textAt the end of November 2022, OpenAI launched ChatGPT, an artificial intelligence chatbot, and it quickly became a world-wide phenomenon. Instantly, it became a subject of controversy and concern as well as praise. Schoolteachers and professors grew worried as ChatGPT was used to create content for everything from high school assignments to scholarly works. Lazy writers aside, ChatGPT’s output has often proved to be inaccurate to the point of complete fabrication. ChatGPT has also regularly misattributed the sources of its information, even giving the wrong author for large blocks of text.With all ChatGPT’s weaknesses, does ChatGPT have any beneficial uses for catalogers and metadata professionals? As a field, information professions are regularly challenged to do more work, more accurately, in less time. Does ChatGPT offer any reliable, accurate services at this time to assist these professionals in completing their tasks?This study seeks to evaluate the weaknesses and strengths of ChatGPT as it tries to perform three common cataloging/metadata tasks: 1) assigning classification numbers, 2) choosing Library of Congress subjects headings, and 3) harvesting keywords. Over the course of four months, it will ask ChatGPT a standardized list of questions on these topics. Then it will collate and evaluate ChatGPT’s performance. In the end, this study will offer its findings as well as best practices for using ChatGPT in cataloging and metadata tasks.Librar
Towards non-contact glucose sensing in aqueous turbid medium at ∼1.1 meters distance
No full textThis work demonstrates a non-contact diffuse reflectance approach with a working distance of ∼1.1 meters for the potential of glucose sensing. Non-contact diffuse reflectance over 1.1-1.3 μm was developed according to a center-illumination-area-detection (CIAD) geometry. The modeled response of diffuse reflectance in the CIAD geometry was examined with phantoms by altering independently the size of the collection geometry and the reduced scattering and absorption properties of the medium. When applied to aqueous turbid medium containing glucose control solutions with the cumulative volume varying over three orders of magnitude, a linear relationship expected for the diffuse reflectance as a function of the medium absorption/reduced-scattering property was observed for four conditions of the glucose-medium composition that differed either in the effective glucose concentration or the host medium scattering property. The cumulation of glucose up to 17.8 mg/dL and 8.9 mg/dL in the host medium having the same optical properties resulted in linear regression slopes of 0.0032 and 0.0030, respectively. The cumulation of the glucose up to 17.8 mg/dL in an aqueous host medium that differed two folds in the reduced scattering property caused the linear regression slope to differ between 0.0032 and 0.0019. The R² values of all cases were all greater than 0.987.Electrical & Computer Engineerin
What is wickedness?: An analysis of the wicked stepmother in literary and film adaptations of the Cinderella story
No full textThis Honors Thesis is a comparative study of different versions of the wicked stepmother character in the Cinderella story. It examines both the history and evolution of the Cinderella tale and the history and evolution of the stepmother trope in the broader world of fairytales. In addition, this paper provides a deep dive analysis into four variations of the character from Charles Perrault's 1697 version, the 1812 version from the Grimm brothers' collection, the 1950 Disney animated film and its sequels, and the 2015 live-action Disney film. Throughout these versions, the stepmother exhibits different degrees of cruel behavior and is motivated by different factors. This paper seeks to determine which versions of the stepmother are truly deserving of the moniker "wicked.