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Sex Work, Race, and Bias: Exploring Police Violence and Misconduct Against Transgender People in the United States
Get PDFTransgender people face widespread abuse and violence from the criminal justice system in the United States, and sociological research has paid more attention to this issue in recent years. Still, there is little research exploring trans peoples’ experiences with the police. Using a framework of intersectional subjection, this paper examines trans peoples’ experiences with police violence and misconduct and how sex work, race, and transphobia affect these relationships. To do so, I use the 2015 United States Transgender Survey to see how engagement in sex work affects trans peoples’ risk of interacting with the police, how sex work and race affect trans peoples’ risk of experiencing police violence, and how being visibly trans to the police affects trans peoples’ experiences with police misconduct. I find that trans women have the highest risk of police interaction among those who had not engaged in sex work, trans men had the highest risk of police interaction among those who had engaged in sex work, non-white trans people who police thought were engaged in sex work had the highest probability of experiencing police violence, and that those who police knew were trans had higher probabilities of experiencing police misconduct when the police believed them to be engaged in sex work. This study adds important context to the widespread police violence facing trans people and to discussions of intersectional subjection
Further Exploration of Heat of Immersion as a Method To Quantify Wettability For Particulates: Effect of Temperature
Get PDFA previous paper by our group concluded that to distinguish between the wettability of different particles, heat of immersion is the best method as opposed to the Washburn or sessile drop method. In this paper, heats of immersion of three different particles with three different wettabilities are measured at different temperatures to examine one critical assumption concerning the temperature dependence of the heat of immersion. In addition, surfactants are added to the water and the effect of surfactant concentration on the heat of wetting is measured. One particularly noteworthy aspect of the current study is that some measurements were made at pressures higher than atmospheric with no more difficulty than measurements made at atmospheric pressure.
The previous paper showed that, for certain particles, the relationship used by us and others between heat of wetting and contact angle gave impossible values for certain surfaces. In this thesis, the derivation of that expression is re-examined and certain assumptions are highlighted. Because of issues with the assumptions, we conclude that using heat of immersion to quantify wetting is perfectly appropriate, but without measurement of the values of liquid-solid interfacial energy with temperature, conversion to the contact angle is likely not appropriate.
Keywords – nanoparticles, wettability, silica, heat of immersion, contact angl
High ambient pressure testing apparatus and demonstration of use for material testing
No full textThis thesis describes the work involved in designing and fabricating a high-ambient pressure chamber for material testing. Using SolidWorks CAD software, an SAE AISI 4340 steel chamber was designed with a simulated design pressure of 60,000 psi and a proof pressure of 30,000 psi. Supporting air, electrical, and sensing systems were also designed for remote operations.
A proof-pressure test was performed where the system reached 30,000 psi and pressure was maintained for 30 minutes with no sign of deformation or failing. Following proof pressure testing, the dive of the DeepSea Challenger to Challenger Deep in the Mariana trench was simulated. Four each of two copper alloys and two aluminum alloys were pressurized in the chamber to 15,400 psi and dimensional measurements, microhardness, and surface images were compared between pretest and posttest data collection.
Analysis of the data indicated that there were statistically significant changes in microhardness averages for the copper alloys at an alpha level of 0.1 for both alloys and an alpha level of 0.05 for one. The aluminum alloys had no statistically significant changes in microhardness average but did have a significant change in variance at an alpha level of 0.1 for both alloys and 0.05 for one. The variance showed a narrowing of distribution around the pretest average data.
Imaging showed changes in topography at magnification greater than 2000x for the aluminum alloys indicative of a possible change in structure which would likely have a corresponding change in material properties but further research is required to confirm and quantify these changes
Two Europe(s)? attitudes towards immigrants across eastern and western Europe
Get PDFConsidering recent immigration trends as well as crises of war which have displaced large numbers of people and led to high rates of migration into and within Europe, understanding how anti-immigrant sentiments develop and how this varies across regions of Europe has become increasingly relevant. This present study examines the differing attitudes towards immigrants between eastern European, post-Soviet, countries and western European countries. Using data from the first nine waves of the European Social Survey (2002 – 2018), which is comprised of a representative sample of the population of Europe, across over 30 countries, I use six questions from the survey asking respondents about their views on specific aspects of immigration to create a scale of general attitudes towards immigrants. I create this scale of a general, latent concept of immigrant attitudes by using a structural equation modeling approach known as Confirmatory Factor Analysis (CFA). With this measurement of immigrant attitudes, I use a MIMIC (Multiple Indicators, Multiple Causes) model to represent the relationship of variables that develop a person’s underlying attitude towards immigrants. Preliminary results point to the existence of two separate concepts of immigration between the east and the west. As both regions have developed differences, this has led to different understandings of immigration and questions about immigrants. These findings present implications for how immigration is understood differently across various regions, as well as socio-political implications
Stable dynamic feedback-based predictive clustering protocol for vehicular ad hoc networks
Get PDFScalability presents a significant challenge in vehicular communication, particularly when there is no hierarchical structure in place to manage the increasing number of vehicles. As the number of vehicles increases, they may encounter the broadcast storm problem, which can cause network congestion and reduce communication efficiency. Clustering can solve these issues, but due to high vehicle mobility, clustering in vehicular ad hoc networks (VANET) suffers from stability issues. Existing clustering algorithms are optimized for either cluster head or member, and for highways or intersections. The lack of intelligent use of mobility parameters like velocity, acceleration, direction, position, distance, degree of vehicles, and movement at intersections, also contributes to cluster stability problems. A dynamic clustering algorithm that efficiently utilizes all mobility parameters can resolve these issues in VANETs.
To provide higher stability in VANET clustering, a novel robust and dynamic mobility-based clustering algorithm called junction-based clustering protocol for VANET (JCV) is proposed in this dissertation. Unlike previous studies, JCV takes into account position, distance, movement at the junction, degree of a vehicle, and time spent on the road to select the cluster head (CH). JCV considers transmission range, the moving direction of the vehicle at the next junction, and vehicle density in the creation of a cluster. JCV's performance is compared with two existing VANET clustering protocols in terms of the average cluster head duration, the average cluster member (CM) duration, the average number of cluster head changes, and the percentage of vehicles participating in the clustering process, etc. To evaluate the performance of JCV, we developed a new cloud-based VANET simulator (CVANETSIM). The simulation results show that JCV outperforms the existing algorithms and achieves better stability in terms of the average CH duration (4%), the average CM duration (8%), the number of CM (6%), the ratio of CM (22%), the average CH change rate (14%), the number of CH (10%), the number of non-cluster vehicles (7%), and clustering overhead (35%).
The dissertation also introduced a stable dynamic feedback-based predictive clustering (SDPC) protocol for VANET, which ensures cluster stability in both highway and intersection scenarios, irrespective of the road topology. SDPC considers vehicle relative velocity, acceleration, position, distance, transmission range, moving direction at the intersection, and vehicle density to create a cluster. The cluster head is selected based on the future construction of the road, considering relative distance, movement at the intersection, degree of vehicles, majority-vehicle, and probable cluster head duration. The performance of SDPC is compared with four existing VANET clustering algorithms in various road topologies, in terms of the average cluster head change rate, duration of the cluster head, duration of the cluster member, and the clustering overhead. The simulation results show that SDPC outperforms existing algorithms, achieving better clustering stability in terms of the average CH change rate (50%), the average CH duration (15%), the average CM duration (6%), and the clustering overhead (35%)
The Story of Colors
Get PDFIn this study, I investigated the evolution of color dimorphism in two bird species, the Western Reef Heron (Egretta gularis) and Dimorphic Egret (Egretta dimorpha), by analyzing their color morphology, geographic distributions, and genomic variation. Both species have white and dark morphs, which coexist in the same environments and share resources. The Western Reef Heron is found in coastal regions of West and East Africa, the Red Sea, the Persian Gulf, and southern India. The Dimorphic Egret has a narrow range, from coastal Kenya and Tanzania to Madagascar and nearby islands
Understanding Veteran Teachers' Basic Psychological Needs in Relation to Their Self-Determined Motivation: An Exploratory Qualitative Study
Get PDFUnderstanding teacher motivation to stay in the classroom can provide insight to teacher retention concerns. The purpose of the study was to determine how veteran teachers’ basic psychological needs related to the veteran teacher’s type of self-determined motivation: autonomous or controlled. 123 Works Task Motivation for Teachers or WTMT (Fernet, Senagal, et al., 2008) survey concerning teaching and classroom management and 20 semi-structured interviews were conducted. The survey scores determined their type of self-determined motivation, while the semi-structured interviews investigated their basic psychological needs. The veteran teachers were grouped together as either autonomously motivated or controlled motivated and then compared. The findings indicated relatedness were a central basic psychological need that provides the value aspect, or the internalization, for the tasks for teaching due to the interlinking with other basic psychological needs through relatedness. According to the Self-Determination Theory (Ryan & Deci, 2017), the values aspect typically comes through autonomy from autonomy supportive leadership such principals. The study’s findings did not support this position of the Self-Determination Theory. The main differences between the autonomous motivated veteran teachers and the controlled were the ways they handled challenges to the satisfaction of basic psychological needs (autonomous motivated teachers used more reflective and personable strategies), and the type of value they see in their relatedness with students (autonomous motivated teachers are intrinsically regulated, while controlled motivated teachers are identified regulated). This was the observed difference that distinguished between autonomous and controlled. The implication of the study indicated the satisfaction of basic psychological needs are more complex and may be situational to the type of profession
The Power of Pause: An Investigation of the Role of Breaks in Creative Performance
Get PDFAlthough studies indicate that intrinsic interest is likely a stronger motivator for creativity than external factors, companies that prioritize creativity have increasingly implemented external motivators into their work environments in the form of respite activities. Despite this growing trend, little research has investigated the usefulness of breaks for promoting creativity. The purpose of the present effort was to address this gap in the literature by exploring the impact of external motivational influences on creative problem-solving performance – specifically, the impact of imposed work breaks, performance pressure, and creative self-efficacy. Participants were asked to take on the role of a product development manager tasked with developing a new restaurant proposal for the firm. Results from the present effort yielded a pattern of findings that demonstrated no significance. However, the findings may still provide valuable insights. More specifically, this study emphasizes the need for more caution when considering the types of tasks used to study motivation in creativity. The findings of the present effort suggest that intrinsically motivating tasks may take priority over externally imposed motivational influences
A supervised machine learning approach to discriminate reservoir fluid presence and saturation in the Gulf of Mexico using frequency and spectral shape attributes
Get PDFThe first chapter in this research aims to define reliable attributes to differentiate subsurface
fluids and measure their attenuation to provide insights into reservoir properties. The study
investigates the effects of fluids and saturations on seismic data by analyzing a frequency-related
suite of attributes using post-stack seismic field data from stacked reservoirs in Ursa Well #1 in
the Gulf of Mexico. The results show that high attenuation reduces higher frequencies, resulting
in a spectrum skewed towards lower frequencies with high kurtosis and low roughness, slope, and
bandwidth. The attribute analysis presents that low amounts of gas saturation exhibit more
attenuation than a fully saturated gas reservoir. Chapter 1 highlights the importance of spectral
analysis, especially the spectrum's shape, in interpreting gas saturation and attenuation effects on
post-stack seismic data allowing successful discrimination of water, oil, and high or low gas
saturations.
Furthermore, the second chapter presents a new workflow that applies supervised machine
learning algorithms to predict the presence of hydrocarbon fluids and their economic viability
using the frequency suite of seismic attributes. K-nearest neighbors, decision tree and random
forest algorithms are tested on datasets for their robustness in classifying the fluid types. The SHAP
values analysis is used to gather information on the importance of each attribute for the
classification of each fluid class. The machine learning models are trained with the Ursa dataset
and subsequentially predict in an expanded area around the training well. The King Kong and Lisa
Anne fields, belonging to a different seismic survey, are used as a validation test for the machine
learning models.
The study concludes that the machine learning models, using the frequency suite of
attributes, can predict water, oil, and high or low gas saturations within clastic reservoirs of the
Miocene Gulf of Mexico. The decision tree and random forest models correctly predicted the fluid
class in three out of four King Kong and Lisa Anne Field wells. The model predictions in the Ursa
blind test expressed reliability in the models after observation of flat spots with correct density
stacking orders. The promising results convey that using supervised machine learning algorithms
for reservoir fluid identification and gas saturation predictions can revolutionize the field of
hydrocarbon exploration and production by providing a more robust way to risk prospects using
exclusively post-stack seismic data and frequency attributes
Laboratory study of durability of recycled concrete aggregate including drainage for use in pavement base course
Get PDFRecycled concrete aggregates (RCAs) have been used as a cost-effective and environmentally friendly material in pavement base construction for quite some time. However, there is a lack of information on the durability, strength, and hydraulic properties of RCA in Oklahoma. The purpose of this study was to generate data on these properties of commonly used RCAs in Oklahoma through laboratory testing and to determine the changes in properties caused by field placement and compaction. Additionally, the performance and costs were evaluated using AASHTOWare Pavement ME simulations. The service life (performance-based) and life cycle cost analyses (LCAs) of aggregate bases of two selected pavements, a flexible pavement (SH-48) and a rigid pavement (SH-33), were studied using the AASHTOWare Pavement ME software. Laboratory testing in this study included particle size distribution, shape indices (angularity and texture), wash loss, optimum moisture content (OMC) and maximum dry density (MDD), Los Angeles (LA) abrasion, durability indices (Dc and Df), hydraulic conductivity (k), and resilient modulus (Mr). The upper and lower limits of Type A gradation, as specified by the Oklahoma Department of Transportation (ODOT), were used for laboratory testing to reduce variability in test results.
It was found that the source material used to produce the RCAs had a significant impact over the quality and properties in terms of stiffness, durability, and performance, with RCAs produced on-site from highways pavements having improved properties compared to those produced in recycling plants. The durability of fines (Df) was found helpful as a screening tool for RCAs since most of the RCAs did not meet the ODOT’s requirements. Also, based on laboratory test results, the permeability of the aggregate bases is expected to exhibit a significant reduction with field placement and compaction. This study also showed that recycled aggregate bases could be built at a lower cost compared to virgin aggregates. The findings suggest that recycled aggregates can be a sustainable and cost-effective alternative for pavement bases, provided that proper selection and quality control measures are implemented