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A User-Friendly Wrapper for DSIDES (Decision Support in the Design of Engineering Systems)
Get PDFWhen dealing with complex systems, we need to consider that these systems have behaviors that are hard to predict or control, and uncertainties are always present since computational models are abstracts of reality. It is recognized that in many situations, it may not be possible to simultaneously optimize all objectives due to inherent conflicts, resource limitations, or uncertainty. As George E.P. Box said: "All models are wrong, but some are useful." The consequences of these observations are significant. We need to accept that our models might not capture everything and that uncertainties are a part of the picture. Hence, we must accept and deal with uncertainty instead of ignoring it and find solutions that are relatively insensitive to the uncertainties.
When choosing a method to work with, we need to consider the quality of our data. To make this all work, we need a method to find solutions that achieve a reasonable compromise or balance among the objectives and identify a set of solutions that are relatively insensitive to uncertainties. Also, be able to facilitate the exploration of solution space to support human decision-making. This ties into the problems we face in supporting decisions for complex systems. These problems involve choosing between options and making compromises.
The compromise Decision Support Problem (cDSP) construct and the Adaptive Linear Programming algorithm has been developed as a result, which was first introduced by Mistree and co-authors (1993). It is a domain-independent, multiobjective decision model based on mathematical and goal programming. They effectively deal with multiobjective problems involving bounds, linear and nonlinear constraints, goals, and consisting of Boolean and continuous variables. The requirements for this construct are:
1) Identify a set of solutions that are relatively insensitive to uncertainties
2) Facilitate the exploration of solution space to support human decision-making
Mistree and co-authors also designed a computer program to implement cDSP construct. It has been written in FORTRAN to identify robust satisficing solutions to design problems when the models are abstractions of reality. It is called DSIDES (Decision Support in the Design of Engineering Systems).
DSIDES is a software tool developed to help engineers and designers make better decisions in the design of complex engineering systems and provides decision support for the design of complex engineering systems.
In this thesis, our primary objective is to enhance the accessibility and user-friendliness of DSIDES by designing a user-friendly wrapper. Three key areas of focus are included in this thesis:
1) Exploration of cDSP Construct: In this part, the examination of the cDSP (Compromise Decision Support Problem) construct, including its structural components and the formulation of problem statements within the cDSP framework, has been discussed.
2) Comprehensive Analysis of the DSIDES Wrapper: A detailed exploration of the DSIDES wrapper and a step-by-step walkthrough of the wrapper's functionalities are covered.
3) DSIDES Software Program Manuals: Program manuals for the DSIDES software has been created. These manuals are helpful resources for individuals seeking to enhance, expand, or modify the software.
Based on these key areas of focus, there are three different parts to this thesis:
1) Part One: DSIDES Software and cDSP Construct: An Introduction.
2) Part Two: Designing the User-Friendly Wrapper for DSIDES.
3) Part Three: Program Manuals and Improvement of DSIDES.
In the following sections, all three parts and their related details are discussed, respectively
A Ceramic Analysis of a Caddo Village Site in the Northern Caddo Frontier: An Archaeological Investigation of the School Land I Site (34DL64) in Delaware County, Oklahoma
Get PDFSchool Land I was a Spiroan Caddo village site positioned near the northern periphery of the Caddo cultural area in present-day northeast Oklahoma. This site was excavated in 1939 and 1940 as a salvage attempt to gather what information they could before the site was destroyed by the subsequent flooding caused by the construction of the Pensacola Dam. The WPA uncovered 15 structures in nine areas along with an assortment of artifacts including ceramics, lithics, and faunal materials. The focus of this thesis is on the ceramic assemblage recovered from School Land I. I analyzed 1,497 ceramic sherds for this study. No whole vessels were recovered. This analysis focused on physical attributes such as size, wall thickness, weight, temper, and surface treatment for all sherds. Diagnostic sherds such as decorated and rim, sherds underwent additional analysis. These ceramic attributes, along with sherd counts and ethnographic evidence, are used to interpret the structures of this site were used. The results of my analysis will show various statistics concerning sherd counts and averages of the individual sherds and such attributes such as tempers, surface treatments, and decorations as they relate to the site as a whole and to individual structures. This data will be used to answer the questions: Are there any differences in the assemblages between buildings? If there is a difference between the structure’s assemblages, do these reflect time of occupation, or do they reflect different purposes and uses of those buildings
Preparation of Field Validation for an All-Digital, Permanent Downhole Pressure Sensor Design
No full textDownhole pressure sensing has become increasingly important in oil and gas operations. Some of the many advancements provided by an improvement in downhole sensing is seen in drilling, stimulation, production forecasting, and wellbore integrity. Currently, downhole pressure sensors on the market are costly, cannot be distributed throughout a wellbore, and have a limited lifespan. As a result, a low-cost, all-digital downhole pressure sensor for permanent, distributed installation is being proposed. The planned sensor will measure pressure up to 10,000 psi with a temperature limit of 250°C. The objective for this study was to design the pressure system, validate the sensor under downhole pressure and temperature conditions in a laboratory apparatus, and to prepare a field validation test of the sensor system.
The pressure housing was designed as a cylinder steel tube surrounding the actual sensor while maintaining a limited outer footprint to withstand the required temperature and pressure. Two different end caps were developed. The first cap was developed to allow fluid flow to the sensor system within the housing without damaging the sensor itself. The second cap was designed to allow the sensor's electrical requirements and pressure reading to be transmitted from the surface to the sensor and vice versa without fluid penetrating the housing. The housing pressure and temperature ratings were validated with finite element modeling. Laboratory tests was performed and showed the pressure sensors behaved as expected. A field installation plan was prepared for installing the sensor in a wellbore. The sensor and reference gauge was successfully placed at a depth of 2,550 feet, run the connection lines for the sensor and reference gauge from the placement depth to the surface and connected them to their respective surface acquisition systems, and sealed the wellbore at the surface at 1.5x hydrostatic pressure about 1,300 psi. A workover rig and crew were used to lower the system into the wellbore and install the wellhead, while a hot oiler truck was used to pressure the wellbore through the wellhead design. Three cyclic pressure tests were conducted, and a drift test of two weeks was successfully done. The field test showed that the sensor was operating within specifications and showed no drift. After the test, we examined the sensors out of the wellbore. There are no signs of leakage; the sensor still functions well
Electrophysiological differences between specialized and multifunctional turtle spinal cord neurons involved in scratching and swimming motor patterns
No full textI examined the electrophysiology of both multifunctional and specialized neurons located in the turtle spinal cord, which are activated during swimming, scratching, and/or flexion reflex. My research analyzes these neurons to determine the electrophysiological differences between neurons that are activated during multiple motor patterns (multifunctional) and neurons that are activated only during a specific movement (scratch-specialized, flexion reflex-selective, and swim-specialized). The differences between multifunctional and specialized neurons could elucidate more about the organization of the central pattern generators (CPGs) located within the spinal cord.
During analysis of intracellular recordings of multifunctional and scratch-specialized neurons, it was determined that most neurons preferred to fire during one phase of activity for both scratching and swimming. Furthermore, the multifunctional neurons could be divided into two groups (hip flexor-on phase preference and hip flexor-off phase preference) based on phase preference.
Analysis of spiking activity in multifunctional and scratch-specialized neurons showed that multifunctional neurons tend to spike more rhythmically than scratch-specialized neurons. When analyzing the peak and trough phases of both multifunctional and specialized neurons it was determined that the multifunctional neurons are probably rhythmically modulated by inhibition more than excitation because the trough phases of activity for both scratching and swimming were significantly correlated for multifunctional neurons, while the peak phases were not. I hypothesize that alternation between the hip extensor and flexor, which are vital for successful scratching and swimming, are occurring due to these multifunctional CPG neurons. Furthermore, since the scratch-specialized neurons and flexion reflex-selective neurons were not as strongly rhythmically modulated, it is likely they are not part of the CPG and instead are responsible for starting scratching activity and flexion reflex, respectively.
Also, this study showed the first swim-specialized neuron, which was tonically excited during swimming, but inactive during scratching. Similar to scratch-specialized neurons, this neuron was not strongly rhythmically modulated, so it is not likely to be part of the CPG. It was activated by each swim stimulation pulse at a relatively short latency. I hypothesize that similar to scratch-specialized neurons, the swim-specialized neuron is responsible for starting the motor pattern.
Taken together, this study provides more insight into the organization of the spinal cord CPG for turtles
Impact of Temporal Order Selection on Clustering Intensive Longitudinal Data Based on VAR Models
Get PDFIn real-world research, intensive longitudinal data (ILDs) are typically collected from a group of individuals of interest, which enables researchers to model not only the within-individual dynamics of the studied processes but also the between-individual differences on the within-individual dynamics. Among the statistical techniques proposed for modeling ILDs of multiple individuals, clustering of intensive longitudinal data provides a meaningful way to quantify sample heterogeneity in dynamic processes, assuming that such heterogeneity reflects the distinct nature of the studied processes.
The aims of this dissertation are threefold: (a) to introduce a VAR-based clustering technique, (b) to examine the impact of temporal order selection on clustering accuracy and parameter estimation by a simulation study, and (c) to demonstrate the application of the clustering technique through an empirical analysis. Specially, I investigated the influence of two temporal order selection strategies: (1) using the most complex structure or highest order (HO) for all individual processes, and (2) using the most parsimonious structure or the lowest order (LO) for all individuals on the performance of two-step model-based clustering procedure. This procedure extracted dynamic coefficients from vector autoregressive (VAR) models and employed the Gaussian mixture model (GMM) and K-means clustering algorithms on the coefficients for cluster identification. Additionally, I also examined whether the influence varied across two clustering algorithms.
The simulation study showed that, regardless of the clustering algorithms used, LO strategy consistently outperformed HO strategy in terms of recovering the number of clusters, cluster membership, and cluster-specific AR and CR effects. GMM performed better than K-means when LO strategy was applied; however, the performance of GMM decreased while the temporal orders increased. Additionally, GMM showed more vulnerability with smaller numbers of participants. The application of the two-step VAR-based method to affect data yielded a meaningful and informative clustering solution, which provided further insights of the uses of the model-based clustering approach Lastly, suggestions and recommendations were offered based on the results of the simulation and empirical analyses
Examining the curricular approach in student affairs as a tool for critical praxis
Get PDFThis qualitative content analysis examines the integration of theoretical frameworks and critical praxis in the curricular approach within student affairs. Data from three departmental curricula at a single institution were analyzed to explore the elements of curriculum design that reflect critical praxis and how theoretical models and frameworks are implemented. The research questions guiding this study focused on identifying the impact of theoretical frameworks on curriculum design and the role of critical praxis for student affairs practitioners.
Despite the lack of explicit guidance on theory selection and integration in curriculum design spaces and the limited attention given to theory application within the curricular approach in higher education literature, this study underscores that the selection of an inherently critical theoretical framework has a significant influence on staff engagement in critical praxis. The findings underscore the importance of grounding curriculum in a critical framework that addresses power dynamics across learning goals and outcomes, advocating for a move towards collective action.
The profession of student affairs has increasingly emphasized justice-oriented practice and challenging the status quo. However, there is a need for practitioners to bridge the gap between individual-level student development and the larger sociocultural contexts in which they operate. The study suggests that to answer this call, theories that engage criticality and foster collective action and reflection must be utilized in curriculum design.
The study also highlights the role of student affairs organizations in shaping practitioners' ability to engage in critical praxis. It identifies the tension between the espoused values of the field and individual practitioners' enactment of those values. While professional associations and graduate preparation programs emphasize social justice and inclusion as competency areas, there is a danger of perceiving expertise in critical work as a static goal, hindering ongoing critical reflection. The findings emphasize the need for practitioners to continuously reflect on their practice and engage with theoretical frameworks to inform curriculum development and learning goals.
Based on the study's findings, three implications for practice are presented. First, theoretical frameworks must move towards collective action to align with the field's goals, moving beyond the sole focus on individual student development. Second, scholars and practitioners should collaborate to produce research on critical praxis in student affairs, with practitioners uniquely positioned to contribute insights from their day-to-day experiences. Third, practitioners need to deeply engage with theoretical frameworks to design curriculum and inform learning goals and strategies, recognizing the transformative power of critical theories on individuals, institutions, and policies.
The study concludes by emphasizing the need for future research to explore the execution of curricula and assess whether learning goals and outcomes are met. It calls for a focus on practitioners' role in shaping student experiences and the complexities they face in navigating student needs, institutional policies, and external pressures while promoting critical practices. Additionally, the study highlights the necessity of developing assessment practices grounded in reflexivity and centered on equity, challenging the neoliberal tendencies in the field. Ultimately, this research aims to inspire conversations and advancements in enacting critical praxis in conjunction with the curricular approach within student affairs, for the benefit of current and future students, as well as practitioners in the field
Record of Disposition by Administration of Faculty Senate Actions, September 2022 - August 2023
Get PDFAdaptation and resilience : the Kiowa people in the nineteenth century
Get PDFThe history of American Indians has historically been viewed through an Anglo-European lens and not from the perspective of the subject population. The aim of this thesis is to give a brief account of the Kiowa people from their perspective and to focus on their hardihood in the face of American aggression. The literature from the late 1800s was largely constructed from observation of the Kiowa and interviews with the Kiowa. While some studies prioritized Kiowa accounts and records most relied most heavily on white observations of the Kiowa. In the 1900s this trend continued and those accounts from the late 1800s became the foundation for any research into Kiowa history and culture. It was not until the second half of the 1900s that many historians began critically evaluating those works and attempts were made to consult with the Kiowa people’s own recollections more often. Since the late 1900s and through to the present more emphasis has been put on the importance of Native narratives when constructing histories about native peoples. The Kiowa are a people who have consistently adapted to the world in which they live, acquiring and making their own elements borrowed from other cultures while retaining a strong cultural and historical identity for themselves. This thesis is a case study, examining the survival and adaption of one people. As such the research methods utilized were qualitative. Texts written by American and European academics were evaluated and compared to as many first-hand Kiowa accounts as could be located. The resulting work reflects as closely as possible a history of the Kiowa during the tumultuous nineteenth century reflecting their own experiences and not those of the dominate white population. This research has found that, though change was often painful for the Kiowa as the United States closed in around them, they successfully adapted to the world in which they found themselves. This was not a new process for them, as they had only acquired the Plains culture sometime in the late 1500s or early 1600s, an event that completely transformed their culture. This shift was even more radical than the one they found themselves faced with in the late 1800s as they were forced to adapt to an American way of life centered on agriculture and commerce
Spatial and Temporal Distribution of Obsidian in Oklahoma: Conveyance Zones on the Southern Plains
Get PDFObsidian is an exotic lithic resource rarely found in Oklahoma, yet it still occurs in the archaeological record. This project utilized Energy Dispersive X-ray Fluorescence (EDXRF) Mass Spectrometry to geochemically source 110 obsidian artifacts from Oklahoma in various private collections and museum collections. These 110 EDXRF samples were added to the existing 220 obsidian artifacts from Oklahoma previously studied to synthesize the data. My research question is: what spatial patterning is expressed by obsidian in Oklahoma, and what do these patterns reveal about cultural interaction through time?
I utilized the interpretive framework of conveyance zones and cultural interaction patterns to interpret the results. All spatial and temporal data was process with ArcGIS to parse out the spatial and temporal distribution of obsidian in Oklahoma. The 110 EDXRF samples resulted in eight chert artifacts, which were removed from the study, leaving 102 EDXRF samples combined with the previous 220 samples totaling 322 obsidian samples in Oklahoma subjected to source characterization. The remaining 102 EDXRF samples from this study resulted in the majority of the obsidian artifacts sourcing to either the Cerro Toledo Rhyolite or Valles Rhyolite obsidian sources in the Jemez Mountains in New Mexico. Obsidian from Malad, Idaho and to a lesser extent Obsidian Cliff, Wyoming were also well represented in the 102 EDXRF samples. Outliers include obsidian from Buck Mountain, California, Timber Buttes, Idaho, and at least one unknown obsidian source.
The results of the synthesized data of the combined 322 obsidian samples from Oklahoma illuminated shifting cultural interaction patterns between the Southern Plains (Oklahoma) and adjacent regions. Until the Late Precontact Period (1,250 – 450 B.P.) and excluding the Paleoindigenous Period (prior to 7,950 B.P.), people on the Southern Plains preferred obsidian from Malad and Obsidian Cliff overall, suggesting a cultural interaction pattern stretching northward through the Central Plains toward Idaho and Wyoming. During the Late Precontact Period those preferences and cultural interaction patterns shifted toward obsidian from the Jemez Mountains in New Mexico with Cerro Toledo Rhyolite being favored by people in the Oklahoma Panhandle, and Valles Rhyolite in western Oklahoma. During the Postcontact Period (450 – 200 B.P.) people in the past in Oklahoma preferred obsidian the Valles Rhyolite obsidian from New Mexico
Heritage Walking: a Popular Geopolitics Study of the AYA Application and its role in Nation-Building and Heritage as a Motivational Factor for Walking
Get PDFThe AYA application (hereafter, app) released by the Chickasaw Nation in 2018, is a fitness app with a gamified rewards system built around the history and culture of the Chickasaw Nation. The Chickasaw Nation as a tribal nation within the US is vulnerable to being assimilated into American culture. Therefore, looking at AYA as a nation-building tool to identify efforts by the Chickasaw government to instill their identity into citizens, is vital to help other endangered cultures. The citizenry’s own desire to learn about their heritage through a rewards system is leveraged by the developers by encouraging physical exertion in the form of walking to achieve progression in the app. However, the app is using an unproven method to reach its goals. Prior walking apps have used history as a motivator but not in tandem with a user’s own heritage sculpted by their government. Government applications are blunter in their approach to nation building, as they create apps purely focused on civic education when related to nation building. It is the combination of walking applications and nation building in AYA that makes it a unique application to test its approach towards fitness through heritage as a motivation for both. A survey was conducted to test users’ feelings towards the Chickasaw Nation and a change in their walking habits. The results show an inconclusive but slight positive correlation between the two. The nation-building aspects of AYA were examined using qualitative coding of the app’s content to discover the main themes used in crafting a heritage for the Chickasaw people to practice. This work highlights the effectiveness of new technologies in promoting national identity and fitness and how they are received when melded together