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Searching the Past, Finding the Present: Identifying Contemporary Tribal Communities in Gilcrease Museum's Rare Books Collection
Get PDFGilcrease Museum staff and scholars embarked on a multi-year project in 2023-2024 to research, identify, and catalog Native American Tribal affiliations within Gilcrease’s rare book collection. The Helmerich Center for American Research (HCAR) houses approximately 4,000 rare books from the Gilcrease Museum. First collected by Thomas Gilcrease (Muscogee Citizen) in the mid-20th century, the collection tells the hemispheric story of the Americas from 1494 to the mid-1900s. A small team at HCAR, including Dr. William (Billy) Smith, Associate Director, Dr. Benjamin Pokross, Duane H. King Post Doctoral Fellow, and Jana Gowan, Reference and Outreach Librarian, began surveying, researching, and documenting the presence of tribal communities and Indigenous creators in the museum’s rare book collection in order to create more accurate and culturally sensitive catalog records while also increasing accessibility to and understanding of the Gilcrease collections. This presentation will provide a general overview of the project design and progress to date and specifically feature the use of the Tribal Nations in Oklahoma Metadata database in support of the project, while also inviting input from the cataloging community
Design And Construction of A Novel Drilling Rig For The Investigation of Hard Rock Drilling for Super-Hot Enhanced Geothermal System Development
No full textThe pursuit of sustainable energy solutions in the face of increasing global demand has fueled interest in super-hot Enhanced Geothermal Systems (EGS). These systems tap into vast, recoverable geothermal energy potential capable of meeting humanity's long-term heat and electricity needs. The traditional geothermal power plants, relying on conventional flash steam or binary cycle technology, demonstrate limited efficiency and incur high capital costs due to the low energy density of available temperatures. Nevertheless, drilling operations targeting super-hot geothermal reservoirs encounter formidable challenges, particularly in igneous basins. Existing drilling technologies and practices often prove inadequate for such harsh conditions, necessitating advancements in drilling methodologies and equipment.
This thesis presents a novel lab-scale drilling rig designed to facilitate the testing and development of technologies for geothermal drilling. Rig construction involved meticulous attention to structural integrity and compatibility with high-temperature test requirements. Integration of sensors facilitated real-time data acquisition for performance analysis. Experimental drilling tests were conducted on sandstone and granite samples, exploring the effects of temperature on drilling rates and bit performance. The data were analyzed to evaluate the drilling efficiency and the impact of temperature on rock strength. Additionally, techno-economic evaluation of the super-hot EGS was carried out, considering factors such as the well cost and resource temperature to investigate the impact of temperature and drilling speed on the levelized cost of electricity. Historical drilling data were used to generate time-to-hit-temperature, cost-to-hit-temperature, and favorability maps for geothermal system development across the United States. The findings of this thesis will contribute to the advancement of drilling technologies and provide insights for strategic decision-making in geothermal resource development
HOW DO CORPORATE POLITICAL CONTRIBUTION STRATEGIES IMPACT FIRMS’ TAX BURDENS?
No full textThis study explores the impact of various firm political action committee (PAC) contribution strategies on the value of political activity. Specifically, I examine how candidate characteristics, contribution timing, and other factors influence a firms’ tax rates. Unlike other studies that examine similar variables, I include these strategies in a single regression, allowing me to determine which are effective while controlling for all the others. I find that firms that focus their contributions on party leadership and those who contribute early pay more taxes than other politically active firms, while those who focus on tax committee members and members of a single party have lower tax rates. Overall, my findings imply that firms should spread their resources broadly, but also target legislators with a direct influence over the desired outcome rather than generally influential legislators
Direct Acylation of 2-Methylfuran with Carboxylic Acids Over Zeolite Catalysts
No full textZeolites have garnered considerable attention in recent years as highly promising catalysts for direct Friedel-Crafts acylation reactions, employing renewable carboxylic acids, leading to the production of a versatile range of high-value fuels and essential commodity chemicals. In particular, the acylation of furanic compounds using carboxylic acids offers an enticing avenue for the sustainable synthesis of surfactants. Despite significant progress in recent years in enhancing our understanding of acylation reactions involving sustainable biomass-derived compounds via heterogeneous zeolite catalysis, there remains a notable knowledge gap concerning certain aspects of catalyst behavior, including activity, stability, and the factors influencing product selectivity.
In chapter 2, the catalyst deactivation mechanisms during acylation are investigated using commercial ZSM-5 zeolites with different Si/Al ratios. The role of 2-MF self-coupling, side reactions with ketenes, and sequential reactions with formed products are decoupled by feeding each species independently and comparing activity loss rates with those of varying surface coverage. The specific reactants employed in this study are 2-methylfuran (2-MF) and acetic acid (AA) to yield the product was 2-acetyl-5-methylfuran (Ac-MF). We reveal that the deactivation constant associated with direct 2-MF adsorption on a clean catalyst surface is approximately twice that of product self-coupling under identical conditions. Co-feeding carboxylic acids improves catalyst stability by diminishing the deactivation rate by several orders of magnitude via inhibiting adsorption of 2-MF and the formed products. Furthermore, evaluating the prominent route toward catalyst deactivation at high acid coverage was determined by systematic modification of surface coverage and the diffusion path of produced products. These results uncover the critical role of acetic acid to limit direct interaction between highly reactive acyl acceptors with surface Bronsted sites. Moreover, the addition of varying partial pressures of non-reactive adsorbent molecules with significant adsorption constants allows manipulation of surface coverage while maintaining the gas phase chemical potential. These experiments show that the product (Ac-MF) reacting with gas phase 2-MF is the primary mechanism of deactivation at high acid coverage, not sequential reactions along the diffusion path or direct interaction of 2MF with the zeolite surface.
Based on the aforementioned results, we proposed that attenuating the acid strength could accelerate the product (Ac-MF) desorption which in return decreases the probability of a sequential reaction between the product and the gas phase 2-MF. A method was developed in chapter 3 involving incorporation of phosphorus in MFI zeolites which leads to decrease the acidity of Brønsted acid site in the catalyst. Here we report the acylation of 2-methylfuran with acetic acid over phosphorus-modified MFI zeolites with various phosphorus loadings. We show that at lower reaction temperatures (160°C), only the sites that are not titrated by phosphorus exhibit activity for acylation. However, when increasing the reaction temperature to 240°C the weaker phosphorus-modified sites begin to exhibit activity for acylation. Interestingly, the phosphorus-modified samples exhibited slower coke formation, and therefore deactivation, due to diminished side reactions.
The active sites in aluminosilicate zeolite have distinct activity that is subjective to several factors associated with the local environment. For example, the proximity of extra-framework aluminum (EFAL) to Brønsted acid sites (BAS) gives rise to distinct active sites exhibiting notably enhanced activity. In chapter 4, we undertake a comprehensive investigation into the acylation of 2-methylfuran (2-MF) using acetic acid (AA) over EFAL-incorporating MFI (Si/Al=40) and BEA (Si/Al=150) zeolites, then contrasting their behaviors after EFAL removal via ammonium hexafluorosilicate (AHFS) washing. EFAL concentrations were measured via solid-state Al27-NMR analysis. Acylation under mild conditions, specifically within the 160-180°C range, remarkably uncovers higher activity over zeolites possessing EFAL, whereas reaction rates experience a pronounced decline post-AHFS treatment. Interestingly, the removal of EFAL leads to a twofold increase in measured activation barriers, aligning them with those observed for all-framework aluminum MFI (Si/Al=140) zeolites. DFT calculations are presented that agree with the experimental activation energies, highlight modifications to adsorbed intermediates and kinetically relevant transition states. Understanding this complex interplay between extra-lattice alumina and Brønsted acid sites is significant for comprehending the underlying factors that govern the kinetics of the reaction and holds key implications for optimizing catalytic performance. This study substantially contributes to understanding of zeolite-catalyzed acylation, offering a pivotal framework to enhance catalytic efficiency within the territory of renewable chemical synthesis.
The properties of acyl donor in acylation reactions play a significant role in determining the behavior of resulting products and their industrial applications in the commodity chemicals. In Chapter 5, we investigate the role of carbon chain length in direct acylation of 2-MF over HZSM-5 zeolite under varied conditions. Our research reveals that reaction rates increase with larger acids, despite the accompanying rise in activation barriers, due to the formation of more stable surface acyl intermediates. This increased stability can be attributed to a stronger adsorption, which was obtained from fitting Eley-Rideal kinetic model. Additionally, our experiments show varying deactivation rates of the catalyst during acylation with different carboxylic acid mixtures, underscoring the importance of co-feeding acetic acid alongside larger carboxylic acids. The addition of acetic acid not only mitigates catalyst deactivation but also maintains product selectivity towards acylation with larger carboxylic acids
Essays in Venture Capital and Entrepreneurship
No full textThis dissertation comprises two essays that investigate the realms of venture capital (VC) and entrepreneurship. In the first essay (Chapter 1), an exploration unfolds to determine whether climate risk serves as a crucial factor in the investment decisions of venture capitalists, and to assess its impact on the entrepreneurial ecosystem. The second essay (Chapter 2) delves into the repercussions of enhanced creditor rights on VC funding structure and its subsequent effects on startup performance.
Chapter 1 examines the association between climate risk and green innovation within startup companies, with a specific focus on the role of VC investors in their consideration of climate risk when making investment decisions. By using the State Climate Adaptation Plans (SCAPs) as sources of exogenous variation to the perceived level of climate risk, we find that startups respond by intensifying their commitment to green innovation, while VC investors correspondingly increase their funding allocation to such environmentally focused startups. However, there is a significant heterogeneity observed among VC investors in terms of their valuation of climate risk within their investment decisions. Notably, experienced VCs do not exhibit a shift in demand towards green startups, a phenomenon that contributes to their long-term success in terms of achieving more favorable exits. Furthermore, we find that the SCAPs adversely affect brown startups in terms of attracting VC funding, while startups operating within the energy sector exhibit an increase in green innovation but fail to secure additional VC financing. These findings hold notable implications for green startups and for VC investors seeking to support green innovation in the face of evolving environmental policies.
Chapter 2 aims to analyze the effects of the Uniform Fraudulent Transfer Act (UFTA) on VC investment strategies and the performance of startups. By utilizing a difference-in-differences framework, the findings indicate that the UFTA inadvertently triggers a sequence of consequences that necessitate VC investors to adjust their investment strategies, giving priority to existing portfolio companies. Consequently, owing to a scarcity of new market entrants, VC investors allocate greater funding to startups with longer durations, thereby leading these startups to rely more heavily on secured debt and experience diminished innovation outcomes subsequent to the implementation of the UFTA. Additionally, under heightened financial pressures, startups display a heightened occurrence of violations, particularly in the realm of employment offenses. Nevertheless, notwithstanding the negative externalities associated with the UFTA, startups financed by experienced VCs exhibit distinctive levels of innovation performance, ultimately facilitating their successful exit through the avenue of initial public offerings (IPOs) in the long run
SPEER23 Survey Report Investigating Climate, Weather, and Energy Attitudes in the United States through the Lens of Social and Psychological Factors
Get PDFReport of the 2023 SPEER Social Survey which includes items on social and political tolerance, as well as weather, climate, and ecological items. Additionally the SPEER23 survey includes social, religious, psychological, political, and demographic questions. Social measures include scales for social capital and racial resentment. Religious questions include ones asking about religious service attendance, religious beliefs, biblical literalism, religious affiliation, and Christian nationalism. Psychological questions measure social dominance orientation, moral foundations, fears, conspiracy, and cultural worldviews. Political items measure party affiliation and left/right orientation. Finally, socio-demographic background questions ask about age, race, ethnicity, sex, gender, family structure, marital status, education, income, urbanicity, and region.Changing seasonal weather patterns and increases in climate-related severe weather have resulted in billions of dollars in damages to property as well as injuries and loss of life across the United States. These climate and weather patterns are expected to continue in the coming decades, depending on the magnitude of global warming, ushering in more frequent heat waves and intensifying the water cycle, which will result in more extreme weather events including severe winter storms, flooding, severe wind, hail, drought, and fire weather (i.e., land and weather conditions that are conducive to wildfires) (IPCC, 2021). Humans do not exist independent of Earth systems, and Earth systems no longer operate independently of human influence, as evidenced by the proposal of a new geologic era - the Anthropocene (Crutzen, 2002). This increase in natural catastrophes and large-scale disasters, both observed over the last few decades and expected in the near future, cause repetitive stress and strain on society in rebuilding and mitigation efforts and create disproportionate vulnerabilities for individuals (Thomas et al., 2019). There are a few studies that focus on how attitudes and behaviors are impacted by natural disasters (e.g., Maki et al., 2019; Rudolph & Kuhn, 2018; Sun et al., 2019); however, most of these studies analyzed data that are limited in sample size, and generally looked at on an aggregated level rather than individual-level attitudes and behaviors. This is not always ideal because data on individual attitudes and behaviors can be used to inform climate-related interventions and policies, as well as increase understanding of the willingness of individuals to help others in need, post-disaster. As a first step towards filling data needs, we conducted an online survey – the inaugural wave and pilot study of the Social, Political, Earth & Environmental Survey – in 2023 (SPEER23 Survey).N
CAN SELF-ORGANIZING TEACHER GROUPS REDUCE TEACHER ISOLATION?
Get PDFThis study investigates the conditions fostering self-organized teacher groups within schools and their relationship to reducing teacher isolation. Utilizing a mixed-methods approach involving 663 online surveys and 18 interviews, the research aimed to identify specific school conditions that encourage teachers to form self-organized groups and assess whether such participation experience decreased feelings of isolation. Findings indicate that self-organized groups, formed under interdependence, independence, and clear goal-setting conditions, are associated with reduced teacher isolation. These groups enable collaborative support without necessitating physical meetings, suggesting that connections within the educational organization can significantly mitigate feelings of isolation among teachers. Although the complexity theory framework does not allow for definitive cause-and-effect conclusions, the study highlights a strong link between supportive conditions for self-organization and lower levels of reported isolation. This research contributes to the educational field by offering insights into how school leaders can cultivate environments that promote teacher autonomy, collaboration, and self-organization, potentially reducing isolation and enhancing the educational setting. The implications extend a call to action for educational leaders and policymakers to foster school cultures that embrace self-organization principles, emphasizing the importance of independent and interdependent work aligned with shared objectives for natural teacher group emergence
Exploration of Factors Influencing the Teacher Self-Efficacy in Educators of Justice-Involved Juveniles in Special Settings: An Explanatory Sequential Mixed-Methods Study
Get PDFJuveniles involved with the justice system are a population of youth with extensive needs who are historically underserved. Legal mandates have attempted to ensure these students are receiving a quality education, but little is known about the educators who are providing services. This explanatory-sequential mixed-methods study sought to identify patterns in demographic characteristics, feelings of teacher self-efficacy, and development of feelings of high teacher self-efficacy in a group of educators of justice-involved juveniles in special settings. Quantitative analysis included descriptive statistics, non-parametric analysis of variance, and non-parametric correlations. Qualitative analysis included an iterative process beginning with a priori codes, leading to development of sub-groupings. Findings suggest this group of participants were moderately efficacious in working with justice-involved juveniles. Group variances indicate females with more life experiences, higher levels of education, and more years of teaching experience tend to score higher on teacher self-efficacy. This group of educators scored slightly higher on Teacher Self-Efficacy scale items that referred to general teaching strategies versus those designed for at-risk or disruptive students, indicating a deficit for working with special populations. Further, this group placed less emphasis on vicarious learning experiences, such as efficacy grained through coursework or observations, in the development of their feelings of high teacher self-efficacy. Implications are discussed regarding future instruction and training of preservice educators to improve feelings of efficacy for working with justice-involved juveniles in special settings
THE DEVELOPMENT OF A NEW KA-BAND NEAR-FIELD PLANAR MEASUREMENT SYSTEM FOR A DIGITAL PHASED ARRAY RADAR
Get PDFA near-field planar scanner is an electromechanical system whose objective is to obtain the far-field pattern of a mostly directive antenna by recording its electromagnetic fields in the near-field region by taking measurements at different points on an imaginary finite plane in front of the antenna under test, the collected data are then mathematically processed to obtain the far-field patterns.
Near-field planar scanners are an excellent solution to the various limitations involved in far-field measurement. This type of system does not require an extremely large anechoic chamber to avoid external and self-interference in a controlled environment and does not require the AUT to rotate or move in any direction, making this system ideal for measuring array antennas. Currently the use of array antennas is proliferating, so the need for affordable systems to test and calibrate them is essential. The objective of this thesis is to provide the design and assembly steps of a low-budget, customizable, open-source near-field planar scanner. This thesis discusses the mathematical equations and theoretical foundations of near-field planar scanners. It also explains our proposed hardware and software design, highlighting the most important considerations. This work also discusses the process to perform an antenna measurement using the present system taking advantage of all its capabilities and finally, this thesis presents the accuracy and correct operation of the proposed scanner
Identifying Traffic Control Mechanism to Improve Level of Service and Resilience in Road Networks based on Topological Credentials
No full textTraffic congestion mitigation strategies often include debating the merit of adding more roads versus optimizing the existing ones. Identifying and improving critical intersections, particularly by adjusting signal control mechanisms, may result in a cost-effective solution. During system disruptions, such as natural or man-made disasters, traffic patterns become unpredictable, leading to gridlocks at certain intersections. It is essential to proactively identify these intersections and apply time and cost-saving solutions. Research has explored various improvement strategies for signalized intersections, such as using actuated controllers or implementing urban traffic control strategies during peak demand. However, the literature does not provide enough guidance on how to prioritize one intersection over the others at the network level to improve level service as well as resilience. Moreover, none of the research conducted network analysis for improving transportation network reconfiguring traffic controllers using node-weighted and full- weighted (both edge and node weight) betweenness centrality (BC). This study presents a new traffic control mechanism technique for improved level of service and resilience in road networks based on topological credentials i.e., rank of relative importance (i.e., node centrality using both edge and node weights) of network elements such as intersections. The goal is to systematically improve the network performance by adopting specific intervention strategies (i.e., traffic controller setup) at certain intersections based on centrality and observing performance metrics such as total travel time, total delay, and Level of Service (LOS).
The study considered the Boise downtown network in Idaho to run these experiments in a simulated environment using Dynamic Traffic Assignment for two specific scenarios (i.e., normal and disrupted) under different network intervention schemes. Results indicate that interventions made at certain intersections improved network performance. For example, changing fixed-time Ring Barrier Controllers (RBC) into actuated RBCs at 8 most important intersections reduces total travel time by 6.7%, total delay by 7.8% and 96 out of 175 turning and through movements at various intersections/nodes experienced better LOS when full-weighted BC ranking is considered. A higher reduction in total travel time (7.8%), total delay (8.8%) and increased number of turning and through movement improvement on intersection in terms of LOS (103 out of 175) is observed when 3 most important intersections are converted into roundabout and rest of the 5 most important intersections into actuated RBCs as per BC ranking. Under disrupted condition (i.e., removing the most important road segment/edge based on the ranking of edge BC measurement of edges of base network), the system performance (total travel time as an indicator) drops down to 96.49% when the original network is assumed to be working at 100% efficiency. After systematically applying node intervention strategies using the full- weighted BC ranking of nodes, the system performance recovers up to 105.95%. Future research should observe system performance by considering a combination of network properties as well as interventions made at other network elements such as roadway segments instead of intersections