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ENHANCING SPECIFIC DIFFERENTIAL PHASE ESTIMATION BY ISOLATING DIFFERENTIAL BACKSCATTERING PHASE TO IMPROVE SEVERE WEATHER DETECTION
No full textPolarimetric radar variables such as differential phase (ф_DP) and its range derivative, specific differential phase (KDP), are critical for improving quantitative precipitation estimation (QPE) and microphysics retrieval. However, conventional estimation methods for KDP are limited by measurement errors and artifacts arising from the differential backscattering phase (δ), particularly in regions of non-Rayleigh scattering. The presence of δ can introduce significant biases in ф_DP measurements, leading to errors in KDP estimates and misinterpretations of polarimetric signatures associated with hail and tornado debris. To address these issues, this study develops and applies a novel processing method that leverages classification techniques and Linear Programming (LP) to simultaneously estimate both KDP and δ, reducing error of bias and standard deviation in KDP estimates. The proposed method is implemented using Level II radar data from the WSR-88D network, specifically focusing on 0.5° plan position indicator (PPI) scans. Three cases are analyzed: a hailstorm with a well-defined positive δ signature and two tornado events exhibiting both positive and negative δ signatures, illustrating the variability introduced by resonance scattering effects. Comparisons between the classification-based LP estimator and the operational least-square-fit (LSF) method demonstrate the ability of the proposed approach to improve KDP estimation and reveal the diagnostic potential of δ for identifying hail and tornado debris. These findings support the use of δ as an additional observational parameter for polarimetric radar-based hazard detection
Exploring the Optimal Design of a Mesoscale Boundary Layer Profiling Network for Model Forecasting Applications in Cases of Significant Severe Weather
No full textRapid advancements to computational capabilities, and the resulting proliferation of high-resolution convective allowing models (CAMs), have recently revolutionized severe weather forecasting. However, CAMs are still far from perfect, and are limited by the availability of observational data. Operational observations directly above Earth's surface are relatively sparse in space and time, leaving much of the three-dimensional structure of the lower troposphere poorly resolved. This under-sampling is likely a major limiting factor to the performance of CAM forecasts, which rely on observations to inform accurate initial conditions of the atmosphere. This is especially relevant to weather phenomena that occur in the atmospheric boundary layer (ABL), where small-scale heterogeneities driven by turbulence are merely parameterized, even in the most sophisticated operational models. Numerous features and processes, some of which play an important role in the evolution of convective storms, also exist in the ABL. A mesoscale network of vertical profiling systems could provide high-resolution observations of these features in addition to the general kinematic and thermodynamic structure of the ABL. Such observations would help to fill some of the data gaps that are likely detrimental to model forecasts of severe convective storms and their hazards. This study uses observing system simulation experiments (OSSEs) to explore how assimilating simulated observations from such networks into CAMs may impact forecast performance for high-impact severe weather hazards such as tornadoes. Additionally, various components of the design and operation of a profiling network are evaluated with the intent of gaining insight into how the network should be optimally designed to provide value while minimizing cost
Community, (Settler) Colonial Collecting, & Commercialization: Patkáša Kšúpi Wòtawe as a Case Study for Interpreting (Dis)Possessed Indigenous Belongings
No full textThis research examines how the meaning and function of dispossessed Indigenous belongings has been and continues to be produced within the broader context of settler colonialism. Centering two Dakȟóta patkáša kšúpi wòtawe, or turtle umbilical amulets, in the collection of the National Museum of the American Indian, as well as the work of the living maker Holly Young (Thizáptaŋna/Wičhíyena Dakȟóta), this thesis proposes a three-part analytical framework to analyze how the function and meaning of these belongings has been altered due to settler colonialism. In the first phase of the analytical framework, how Indigenous belongings function within community, I highlight how patkáša kšúpi wòtawe function as a microcosm for land-based epistemologies, specifically kinship and cyclical conceptions of time. Phase two, which focuses on colonial or settler colonially dispossessed Indigenous belongings, highlights how the structures of settler colonialism relegate patkáša kšúpi wòtawe as an ethnographic specimen, negating the individuality and sovereignty of their maker. The final phase, commercialization, gives a brief overview of the history of Native artists explicitly engaging with the art market and how living makers, such as Holly Young, can be seen as facilitators of tribal resilience and resist ongoing settler colonialism. Ultimately, this thesis aims to destabilize and challenge the steadfast settler colonial epistemological and semiotic structures of knowledge production regarding removed Indigenous belongings. Theoretically framing my analysis within post-structuralist semiotics, I employ a combination of anticolonial methodologies, such as centering oral histories and scholars, and the voice of living makers with Western art historical methods like close visual analysis and archival research
The Response of Mineral-Associated Organic Matter to Drought Conditions And The Signatures of Land Use in Sediment Loading in Central Oklahoma
No full textSoil organic carbon (SOC) acts as a significant terrestrial carbon sink, and its turnover is a factor of the different pools of SOC in a soil. Mineral-associated organic matter (MAOM) is considered to be a particularly stable SOC pool. MAOM is protected from microbial respiration primarily through strong chemical bonds between the OC and mineral, promoting soil carbon storage. Despite this inherent stability, MAOM turnover has been found to depend upon climatic conditions and the physiochemical properties of a given soil. Thus, there is a need to evaluate MAOM stability across different climates while simultaneously considering the mineralogical controls on MAOM storage. In Central Oklahoma, changes in the amount and frequency of rainfall are anticipated due to climate change. To assess the impact of a changing climate on SOC, we characterized total SOC and MAOM-C in soil samples from a field-manipulated rainfall gradient in an existing temperate prairie. We hypothesized that there would be alterations to total SOC and MAOM-C concentrations in response to a simulated drought experiment. Soils were analyzed following the 4-year DroughtNet experiment at the Kessler Atmospheric and Ecological Field Station in Central Oklahoma. Here, shelters were constructed so that soil plots received a controlled amount of precipitation ranging from 50% addition to 100% exclusion of the natural precipitation. Changes in C concentrations were evaluated following a series of extractions that separate MAOM-C based off the crystallinity of the iron or aluminum oxide to which it was bound. We further hypothesized that the response to precipitation treatments would be evident within these pools of increasingly stable metal species with more crystalline species increasingly holding C in drought conditions. However, no statistically significant relationships were identified between total SOC or MAOM-C pools and precipitation. Still, the most abundant pools of Fe and Al species were identified as well as to what species most of the MAOM-C was likely bound. We found that soil Fe was mostly in the form of crystalline iron oxides. However, the extractable MAOM-C was preferentially bound to less crystalline Fe species such as short-range order (SRO) Fe-(hydr)oxides or Fe found in the form of organo-metallic associations. Al species were more abundant than Fe species in these less crystalline states. Interestingly, much of the MAOM-C remained following the removal of these reducible metal-oxide species. Using X-ray diffraction, we confirmed the presence mixed layered 2:1 phyllosilicate clays that likely hold the remainder of the C in the < 53 µm MAOM fraction. The preferential adsorption of C to less crystalline, more reactive metal species and clay could result in MAOM vulnerability over a greater timescale. However, the whole soil SOC as well as the MAOM-C fractions appear to be stable across the precipitation gradient and are governed by soil texture rather than moisture. Excessive loading of sediment into waterbodies has been shown to severely diminish water quality. In Norman, Oklahoma, this issue impacts a source of drinking water for the residents, Lake Thunderbird. Here, we evaluated potential sources of soil erosion that could cause high suspended sediment within this watershed. Specifically, we conducted geochemical analysis on suspended sediment collected using a passive sediment trap deployed in Dave Blue Creek, a stream which feeds into Lake Thunderbird. We compared the suspended sediment to soil in surrounding areas that were representative of potential source groups. These source areas were ultimately grouped by land use: grasslands, tree cover, and developed land as classified by the National Land Cover Database (NLCD). We hypothesized that most of the suspended sediment in Dave Blue Creek would originate from upland urban soils. Using the Sediment Source Assessment Tool (Sed_SAT), we obtained unique geochemical fingerprints for each source group and were able to characterize changes in sediment input contributions. We successfully identified contributing sources to the suspended sediment in Dave Blue Creek based off land use. However, we found that we were unable to differentiate between bank and upland sources of the same land use. Still, clear contributions from developed land were identified across all suspend sediment samples. Additionally, we found that during the sampling periods with more precipitation and higher discharge in the stream, there was a strong grassland signature. Only in the month will little precipitation and low discharge were tree-covered land inputs detected. Overall, our results indicated that erosion control strategies in the Lake Thunderbird watershed should focus on ensuring bank stability in developed areas and mitigating run-off in grasslands
Biophilic Design for Sensory and Emotional Wellness in Healthcare Facilities
No full textThe spaces we inhabit shape our experiences, emotions, and well-being—perhaps nowhere more so than in healthcare environments. While patient-centered design has long been a focus in medical settings, less attention has been given to how the built environment impacts visitors, caregivers, and therapists—those who provide emotional and physical support but often navigate these spaces under stress. This study explores the potential of biophilic design, the integration of natural elements into architecture, to foster sensory and emotional well-being for these non-patient users in healthcare facilities. Grounded in Florence Nightingale’s Environmental Theory, this research examines how elements such as natural light, greenery, soundscapes, biomimicry, and tactile pathways contribute to reducing stress, enhancing emotional resilience, and encouraging social interaction. Through a systematic literature review and a quantitative survey, the study gathers insights from a diverse participant group to assess perceptions of biophilic design features in public spaces within healthcare environments. The findings provide evidence-based recommendations for designing more restorative and inclusive healthcare spaces that go beyond patient care. By prioritizing the experiences of visitors, caregivers, and therapists, this research advocates for a more holistic approach to healthcare design—one that acknowledges the profound impact of space on mental and emotional well-being. This study contributes to the growing discourse on human-centered, sustainable, and emotionally responsive architecture, offering practical insights for designers, architects, and healthcare administrators looking to create healing environments for all who enter them
TECHNOLOGICAL AFFORDANCES IN 360-DEGREE VIDEO VIEWING APPARATUS: A STUDY OF TECHNOLIGICALY TRIGGERED HEURISTICS AND THEIR EFFECT ON USER ATTITUDES ABOUT 360-DEGREE VIDEO TRAVEL ADVERTISEMENTS
No full textAbstract360-degree travel advertisement videos can be beneficial to destinations that are trying to showcase themselves to potential visitors. The various technologies used to view these videos have become more affordable and more accessible, allowing destinations to consider using these systems in displays at travel conventions as opposed to traditional videos on monitors. This thesis examined how different viewing systems could impact the effectiveness of a 360° video advertisement in changing a viewer’s opinion of a destination and their desire to visit the destination. This thesis used the Main Model to measure the effects on viewers provided by different technological affordances of the viewing systems. The viewing systems being focused on for this study are a head-mounted display (HMD) and a motion-controlled tablet. This study was a 2 (viewing system: HMD/tablet) x 2 (destination: butterfly garden/air & space museum) repeated-measures experiment, where the destination was the within-subjects factor, and the viewing system was the between-subjects factor. The destinations were 360-degree video advertisements with narrated audio elements lasting one minute. The viewing systems will be a Meta Quest 3 head-mounted display and an iPad 10 motion-controlled tablet. Participants were randomly assigned to the different viewing systems, and the order of their video advertisements was randomized. The two destinations that participants were shown ads for are the Tulsa Air and Space Museum and the Texas Discovery Butterfly Gardens. Repeated measures and comparative mean analysis were run on the data in SPSS to answer the 10 hypotheses posed in this study. Results indicated a significant increase in the feeling of presence, the association of novelty to the viewing system, and the intention to visit. The outcomes, limitations, and conclusions are discussed in the corresponding sections of the paper
The influence of positive and negative mood on the weapon focus effect
No full textThis study explores the relationship between mood and the weapon focus effect (WFE), with a specific focus on how pre-existing mood influences recollection in the presence of a weapon. Two different hypotheses were tested. First, I proposed that mood would moderate the WFE by affecting how unusualness influences attention. Secondly, I hypothesized that mood might directly influence the WFE through a mood-congruence effect. A total of 301 participants’ mood was manipulated and then they were exposed to different scenarios involving a threatening (vs. non-threatening) object in an unusual (vs. usual) contexts. The results provided partial support for the mood-congruence hypothesis, suggesting that negative mood increased attention to a threatening stimulus in a usual context, and subsequently leading to the WFE (i.e., reduced recollection of details about a person holding a weapon). Specifically, consistent with a mood congruence effect, in the negative mood condition, participants displayed reduced recollection for a person-target when the weapon appeared in a usual context. Unexpectedly, however, participants displayed increased recollection when the weapon appeared in an unusual context. These findings suggest that mood influences weapon-biased recollection. The results may have important implications for eyewitness testimony by highlighting the importance of considering pre-existing emotional states when evaluating eyewitness’s memory accuracy
BEAD WIDTH AND HEIGHT EFFECTS ON POLYMER ADDITIVE MANUFACTURING MATERIAL PROPERTIES
No full textUltem 9085 resin is used notably in aerospace applications due to a combination of its high performance mechanically and thermally for a thermoplastic, processability as a thermoplastic, and achieving flame smoke toxicity (FST) ratings. Additive manufacturing (AM) has become a prominent manufacturing method for this material in aerospace use as it has achieved certifications for airworthiness which substantiates it’s use on planes. Differences in mechanical properties between different bead widths and heights have been noted however a more complete analysis of bead width and height with changing mechanical properties is needed for FDM printed thermoplastics for the link between these properties to be explored. The present work aims to establish a dataset of these values, made specifically with a material of interest for use, so that the link between these values and mechanical properties can be investigated. In this thesis XY, YX and +/- 45deg samples of Ultem 9085 were fabricated with varying bead widths and heights utilized during printing across two nozzle size selections which were then tensile tested per ASTM D638 standard to create a dataset for analyzation. This dataset was then analyzed to look for trends for exploring the link between the two. During this process direct image correlation (DIC) was taken with a portion of samples in addition to scanning electron microscopy imaging of breakages for any potential insights these could provide to the data, batches of samples that were noted to have a flaw within any of the batch were retained and tested for any insights that could be gathered in future works regarding printing defects