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A Retrospective, Machine-learning Assisted Analysis of Seismic Sequence Migrations in Oklahoma and Delineating Fault Structures
Get PDFSeismogenic fault geometries are important to understanding the seismic potential of fault slip in natural systems. Their orientation relative to the principal tectonic stress directions control their susceptibility to slip. While fault orientations can be ascertained through detailed field mapping or subsurface imaging, rapid automatic identification of fault structures may be useful for future seismic hazard analysis. We apply a methodology workflow that can be automated and utilize central Oklahoma seismicity since 2010 as a test of the concept. To conduct this retrospective analysis, we utilize a Python package, easyQuake, that was recently developed by the Oklahoma Geological Survey (OGS), to augment their earthquake monitoring via pickers that are trained on millions of seismograms with neural network deep learning. The easyQuake software was used to analyze seismic data collected from 2009 to 2015 - specifically to investigate the possible migration of earthquake nucleation in the Jones, Oklahoma region - as well as increase the catalog completeness and accuracy. Jones is the area of interest for this study as it was an early case study for large volume (~1 Mbbl/mo) wastewater injection inducing earthquakes at greater than 10 km distances. The software outputs a catalog in QuakeML format, of which the associated metadata, such as pick times, can be read into hypoDD format. The catalog is then relocated with hypoDD to explore cluster and fault geometries, as well as earthquake sequence migration. With the hypoDD results, we utilize machine-learning techniques packaged in the Python machine-learning library scikit-learn for spatial clustering (e.g., DBSCAN) followed by linear regression (e.g., RANSAC) of those clusters to identify suspected fault segments. We identified potential instances of previously unmapped, seismically active segments in the Jones area and plan to expand the analysis to examine a wider range of the state’s fault segments and more current seismic sequences. Many of the segments mapped would not have been identifiable without the expansion of the microseismic catalog easyQuake provides. This type of work improves our understanding of the seismic hazard as it increases the database of known fault segments throughout the broader region and shows that these seismogenic fault segments can be identified automatically
Synthesis, Characterization, and Modeling of Aligned ZnO Nanowire-Enhanced Carbon-Fiber-Reinforced Composites
Get PDFThis paper presents the synthesis, characterization, and multiscale modeling of hybrid composites with enhanced interfacial properties consisting of aligned zinc oxide (ZnO) nanowires and continuous carbon fibers. The atomic layer deposition method was employed to uniformly synthesize nanoscale ZnO seeds on carbon fibers. Vertically aligned ZnO nanowires were grown from the deposited nanoscale seeds using the low-temperature hydrothermal method. Morphology and chemical compositions of ZnO nanowires were characterized to evaluate the quality of synthesized ZnO nanowires in hybrid fiber-reinforced composites. Single fiber fragmentation tests reveal that the interfacial shear strength (IFSS) in epoxy composites improved by 286%. Additionally, a multiscale modeling framework was developed to investigate the IFSS of hybrid composites with radially aligned ZnO nanowires. The cohesive zone model (CZM) was implemented to model the interface between fiber and matrix. The damage behavior of fiber was simulated using the ABAQUS user subroutine to define a material’s mechanical behavior (UMAT). Both experimental and analytical results indicate that the hierarchical carbon fibers enhanced by aligned ZnO nanowires are effective in improving the key mechanical properties of hybrid fiber-reinforced composites.Ye
Started from the Middle, Now We're Here: Making a Game Plan for Metadata Justice at the Dickinson Research Center
Get PDFThe Dickinson Research Center (DRC) at the National Cowboy & Western Heritage Museum has implemented new online databases for photograph and manuscript collections. As legacy materials were transitioned into ArchivesSpace and Islandora, staff recognized the need to better understand the existing metadata and the necessity of a plan of action to move toward equitability. However, that process has not been without its challenges - the biggest of which was knowing where to start. This presentation will discuss how DRC database projects are evolving from just improving accessibility to also incorporating metadata justice
Food environments and gut microbiome health: availability of healthy foods, alcohol, and tobacco in a rural Oklahoma tribal community
Get PDFBackground
Prior research suggests that dysbiotic gut microbiomes may contribute to elevated health risks among American Indians. Diet plays a key role in maintaining a healthy gut microbiome, yet suboptimal food environments within American Indian communities make obtaining nutritious food difficult.Objective
This project characterizes the retail food environment within a rural tribal community, focused on the availability of foods that enhance the health and diversity of the gut microbiome, as well as products that reduce microbiome health (alcohol and tobacco).Design
Audits were conducted of all retail stores that sell food within nine communities within the Cheyenne & Arapaho Tribal Jurisdictional Area in western Oklahoma.Main measures
Freedman Grocery Store Survey.Key results
Alcohol and tobacco were generally far more available in stores than foods that support a healthy gut microbiome, including fruits, vegetables, lean meats, and whole grain bread. Out of the four store types identified in the study area, only supermarkets and small grocers offered a wide variety of healthy foods needed to support microbiota diversity. Supermarkets sold the greatest variety of healthy foods but could only be found in the larger communities. Convenience stores and dollar stores made up 75% of outlets in the study area and offered few options for maintaining microbiome health. Convenience stores provided the only food source in one-third of the communities. With the exception of small grocers, alcohol and tobacco products were widely stocked across all store types.Conclusions
The retail food environment in the Cheyenne & Arapaho Tribal Jurisdictional Area offered limited opportunities for maintaining a healthy and diverse microbiome, particularly within smaller rural communities. Additional research is needed to explore the relationship between food environment, dietary intake, and microbiome composition. Interventions are called for to increase the availability of “microbe-friendly” foods (e.g., fresh produce, plant protein, fermented and high fiber foods) in stores.Ye
Toward a framework for alleviating technostress: The role of affect state
No full textThe objective of this dissertation proposal is to design a general framework for interventions aimed at alleviating the impact of technostress, that is, stress occurring when individuals use information technology (IT) devices. Initially noted as a modern disease of adaptation due to the inability of individuals to cope with IT, technostress is increasing in scope and becoming a serious health concern. IT use has generally enhanced individual and workplace productivity but is creating high levels of technostress among individuals, reducing their task performance, and leading to long-term health consequences. High levels of stress directly impact a person’s health and is a demonstrated risk factor for anxiety, depression, and cardiovascular diseases, as well as for diabetes and obesity, because stressed people crave for food high in sugar and fat.
Researchers have recognized technostress, alerted us to its detrimental effects on health, identified specific stressors, such as interruptions through pop-ups, but research has not fully addressed methods that can be enacted by individuals to alleviate technostress. Furthermore, affect, although mentioned as an important factor in stress, has not been investigated as regard to technostress. Using the findings on the interplay between affect and stress in the neurophysiology literature, our study addressed this gap by investigating the role played by individuals’ affect state in shaping their response to a stimulus. Hence, we propose a framework that integrates the biological underpinnings and the psychological processes of stress and set affect as an important construct in this framework. We posit that the user’s affect can be leveraged to minimize the negative effects of episodic stressors during their interactions with technology. In this proposal, affect is defined as a neurophysiological state resulting from the evaluation by individuals of a specific stimulus to which they are exposed, and we focus on stimuli occurring during an individual’s interaction with technological devices. A stimulus evaluated as bad will result in a negative affect state, while a stimulus assessed as good will result in a positive affect state. Feeling is the conscious experiencing of an affect state.
Affect state can impact the individual’s attention scope, cognitive flexibility, and appraisal of stimuli that arise from their environment. Based on the neurophysiological underpinnings of stress, we posit that an individual’s affect state is a moderator of the relationship between exposure to a stimulus and the appraisal processes of that stimulus. More specifically, users in a positive affect state are less likely to assess a stimulus as distressful compared to their counterparts in a neutral or negative affect state (primary appraisal). Moreover, if the stimulus is appraised to be a distressful stimulus, users in a positive affect state are more likely to appraise the distress as controllable (secondary appraisal) and adopt a more effective coping strategy compared to their counterparts in a neutral or a negative affect state. Proceeding from these observations, we present a framework that emphasizes the roles played by affect state, appraisal, and coping strategies in the stress process, and how affect influences both appraisal and coping to shape an individual’s response to a stimulus.
To test our hypotheses, we conducted an online randomized controlled experiment with individuals at least 18 years old recruited from a university campus. During the experimental session, we induced specific affect states in the participants at the beginning of the session, and then ask them to perform a cognitive task on a computer while they are being exposed to frequent pop-up messages, which are identified in prior IS research as stimuli that could create technostress. There were three experimental groups reflecting three different induced affect states (positive; negative; or neutral). These affect states were induced by asking the participants to look at pictures selected the from the Nencki Affective Picture System (NAPS; Marchewka et al. 2014) that have been demonstrated to induce different affect states.
Technostress being a biopsychological response, we used a combination of perceptual and physiological measures to record the participants’ response to the experimental stimuli. The perceptual measures included questionnaires of affect, cognition, and stress appraisal. The physiological measures consisted of participants’ facial expressions.
Our study found that positive affect state was associated with appraising pop-up messages as less of a threat compared to negative affect state. Also, individuals in the positive affect condition appraised the pop-up messages to be more controllable and were more likely to adopt adaptive coping strategies (positive reframing, planning, and active coping) compared to participants in a negative affect state. Finally, participants’ task performance was influenced by the type of coping strategies they had adopted to deal with the pop-up messages, with support seeking and maladaptive coping being associated with lower performance scores.
Our research contributes to the emergent science on technostress by suggesting methods to alleviate impact of stressors, and provides guidelines for managing technostress to individuals and public policy makers. From a theoretical standpoint, we propose a framework that incorporates the biological mechanisms of stress and addresses the role of affect in shaping the stress response. From a methodological perspective, we use a combination of perceptual and physiological methods to gauge individuals’ stress response, demonstrating the value of non-invasive methods such as facial expressions as objective tools for measuring individuals’ responses to episodic stressors
Masculine methods: travel narratives and scientific authority in early Victorian Britain
Get PDFFeminist formulations have rightly impacted the history of science. In this thesis, I show how in the context of 19th Century Britain, men of science appealed to contemporary norms of masculinity to claim masculine virtues and epistemic authority. British men of science used colonial modes of knowledge production and in doing so asserted their epistemic authority over and in relief of the knowledge of women and Indigenous people. Individual men of science used travel narratives to exhibit virtues associated with heroic voyagers. In their travel narratives, men of science like Charles Darwin exaggerated danger and omitted accounts of assistance to present a particularly British masculinity that exalted independence and stoicism. Charles Darwin’s Voyage of the Beagle was a wildly popular, public-facing travel narrative. Thomas Huxley, who adopted the moniker ‘Darwin’s Bulldog’, also wrote a travel narrative that was published under very different conditions. Darwin’s travel narrative was published at the beginning of his career as an important work of self-fashioning. In contrast, Huxley’s Diary of the Voyage of H.M.S. Rattlesnake was published post-humously from an unpublished diary. In contrasting Charles Darwin’s public-facing travel narrative and Thomas Huxley’s more private travel diary we can see how a man of means could afford to avoid the riskiest parts of doing colonial science while asserting their total independence and stoicism. Specifically, perilous masculine experiences became a prerequisite for producing knowledge and telling an exaggerated story of peril became a reliable means of accruing epistemic authority in the scientific community. The production and distribution of the scientific travel narrative, for both scientific and popular consumption, was a direct response to concerns about the decline of British science that Charles Babbage pointed out in 1830, which highlighted the beleaguered state of British science, particularly when compared to the success of French theoretical science
Aerial photo index, Muskogee County, OK. Section 6 of 15
No full textAerial photograph index (photomosaic), Muskogee Co. Okla. -AU- MAP 6 of 1
Aerial photo index, Muskogee County, OK. Section 9 of 15
No full textAerial photograph index (photomosaic), Muskogee Co. Okla. -AU- MAP 9 of 1
Aerial photo index, Hughes County, OK. Section 5 of 9
No full textAerial photograph index (photomosaic), Hughes Co. OKLA . -AWH- MAP 5 of
