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Brain Computer Interface (BCI) Applications: Privacy Threats and Countermeasures

Description: In recent years, brain computer interfaces (BCIs) have gained popularity in non-medical domains such as the gaming, entertainment, personal health, and marketing industries. A growing number of companies offer various inexpensive consumer grade BCIs and some of these companies have recently introduced the concept of BCI "App stores" in order to facilitate the expansion of BCI applications and provide software development kits (SDKs) for other developers to create new applications for their devices. The BCI applications access to users' unique brainwave signals, which consequently allows them to make inferences about users' thoughts and mental processes. Since there are no specific standards that govern the development of BCI applications, its users are at the risk of privacy breaches. In this work, we perform first comprehensive analysis of BCI App stores including software development kits (SDKs), application programming interfaces (APIs), and BCI applications w.r.t privacy issues. The goal is to understand the way brainwave signals are handled by BCI applications and what threats to the privacy of users exist. Our findings show that most applications have unrestricted access to users' brainwave signals and can easily extract private information about their users without them even noticing. We discuss potential privacy threats posed by current practices used in BCI App stores and then describe some countermeasures that could be used to mitigate the privacy threats. Also, develop a prototype which gives the BCI app users a choice to restrict their brain signal dynamically.
Date: May 2017
Creator: Bhalotiya, Anuj Arun

Case Studies to Learn Human Mapping Strategies in a Variety of Coarse-Grained Reconfigurable Architectures

Description: Computer hardware and algorithm design have seen significant progress over the years. It is also seen that there are several domains in which humans are more efficient than computers. For example in image recognition, image tagging, natural language understanding and processing, humans often find complicated algorithms quite easy to grasp. This thesis presents the different case studies to learn human mapping strategy to solve the mapping problem in the area of coarse-grained reconfigurable architectures (CGRAs). To achieve optimum level performance and consume less energy in CGRAs, place and route problem has always been a major concern. Making use of human characteristics can be helpful in problems as such, through pattern recognition and experience. Therefore to conduct the case studies a computer mapping game called UNTANGLED was analyzed as a medium to convey insights of human mapping strategies in a variety of architectures. The purpose of this research was to learn from humans so that we can come up with better algorithms to outperform the existing algorithms. We observed how human strategies vary as we present them with different architectures, different architectures with constraints, different visualization as well as how the quality of solution changes with experience. In this work all the case studies obtained from exploiting human strategies provide useful feedback that can improve upon existing algorithms. These insights can be adapted to find the best architectural solution for a particular domain and for future research directions for mapping onto mesh-and- stripe based CGRAs.
Date: May 2017
Creator: Malla, Tika Kumari

Catalytic Properties and Mechanical Behavior of Metallic Glass Powders

Description: Lack of crystalline order and microstructural features such as grain/grain-boundary in metallic glasses results in a suite of remarkable attributes including very high strength, close to theoretical elasticity, high corrosion and wear resistance, and soft magnetic properties. By altering the morphology and tuning of composition, MGs may be transformed into high-performance catalytic materials. In this study, the catalytic properties of metallic glass powders were demonstrated in dissociating toxic organic chemicals such as AZO dye. BMG powders showed superior performance compared to state of the art crystalline iron because of their high catalytic activity, durability, and reusability. To enhance the catalytic properties, high energy mechanical milling was performed to increase the surface area and defect density. Iron-based bulk metallic glass (BMG) of composition Fe48Cr15Mo14Y2C15B6 was used because of its low cost and ability to make large surface area by high energy ball milling. AZO dye was degraded in less than 20 minutes for the 9 hours milled Fe-BMG. However, subsequent increase in ball milling time resulted in devitrification and loss of catalytic activity as measured using UV-Visible spectroscopy. Aluminum-based bulk metallic glass (Al-BMG) powder of composition Al82Fe3Ni8Y7 was synthesized by arc-melting the constituent elements followed by gas-atomization. The particle size and morphology were similar to Fe-BMG with a fully amorphous structure. A small percentage of transition metal constituents (Fe and Ni) in a mostly aluminum alloy showed high catalytic activity, with no toxic by-products and no change in surface characteristics. Al-alloy particles, being light-weight, were easily dispersed in aqueous medium and accelerated the redox reactions. The mechanism of dye dissociation was studied using Raman and Infrared (IR) spectroscopy. Breaking of -C-H- and - C-N- bonds of AZO dye was found to be the primary mechanism. Mechanical behavior of individual BMG particles was evaluated by in situ pico-indentation in a scanning electron ...
Date: May 2017
Creator: Garrison, Seth Thomas

Development of an Outcome Measure for Use in Psychology Training Clinics

Description: The ability to monitor client change in psychotherapy over time is vital to quality assurance in service delivery as well as the continuing improvement of psychotherapy research. Unfortunately, there is not currently a comprehensive, affordable, and easily utilized outcome measure for psychotherapy specifically normed and standardized for use in psychology training clinics. The current study took the first steps in creating such an outcome measure. Following development of an item bank, factor analysis and item-response theory analyses were applied to data gathered from a stratified sample of university (n = 101) and community (n = 261) participants. The factor structure did not support a phase model conceptualization, but did reveal a structure consistent with the theoretical framework of the research domain criteria (RDoC). Suggestions for next steps in the measure development process are provided and implications discussed.
Date: May 2017
Creator: Davis, Elizabeth C.

The Effects of Air Pollution on the Intestinal Microbiota: A Novel Approach to Assess How Gut Microbe Interactions with the Environment Affect Human Health

Description: This thesis investigates how air pollution, both natural and anthropogenic, affects changes in the proximal small intestine and ileum microbiota profile, as well as intestinal barrier integrity, histological changes, and inflammation. APO-E KO mice on a high fat diet were randomly selected to be exposed by whole body inhalation to either wood smoke (WS) or mixed vehicular exhaust (MVE), with filtered air (FA) acting as the control. Intestinal integrity and histology were assessed by observing expression of well- known structural components tight junction proteins (TJPs), matrix metallopeptidase-9 (MMP-9), and gel-forming mucin (MUC2), as well known inflammatory related factors: TNF-α, IL-1β, and toll-like receptor (TLR)-4. Bacterial profiling was done using DNA analysis of microbiota within the ileum, utilizing 16S metagenomics sequencing (Illumina miSeq) technique. Overall results of this experiment suggest that air pollution, both anthropogenic and natural, cause a breach in the intestinal barrier with an increase in inflammatory factors and a decrease in beneficial bacteria. This evidence suggests the possibility of air pollution being a potential causative agent of intestinal disease as well as a possible contributing mechanism for induction of systemic inflammation.
Date: May 2017
Creator: Fitch, Megan

The Impact of Causative Genes on Neuropsychological Functioning in Familial Early-Onset Alzheimer's Disease: A Meta-Analysis

Description: Mutations of three genes encoding amyloid precursor protein (APP), presenilin-1 (PSEN1), and presenilin-2 (PSEN2) have been shown to reliably result in familial early-onset Alzheimer's disease (FAD); a rare, but catastrophic, subtype of Alzheimer's disease (AD) marked by symptom emergence before age 65 as well as accelerated cognitive deterioration. The current study represents the first known meta-analysis on the association of APP, PSEN1 or PSEN2 on neurocognitive variables. A total of 278 FAD mutation-carriers (FAD-MC) and 284 cognitively healthy non-mutation-carriers (NC) across 10 independent investigations meeting inclusion criteria were chosen for the current meta-analysis (random effects design). Findings revealed an overarching trend of poorer performance by FAD-MC individuals compared to NC individuals across the majority of cognitive domains identified. Significant differences in effect sizes suggested FAD-MC individuals exhibited worse performance on measures of attention, explicit memory, fluency, primary memory, verbal, and visuospatial functioning. Findings indicative of differential sensitivity to cognitive domain impairments across FAD-MC and NC groups inform neuropsychological descriptions of individuals in preclinical phases of FAD.
Date: May 2017
Creator: Smotherman, Jesse M

Improving the Gameplay Experience and Guiding Bottom Players in an Interactive Mapping Game

Description: In game based learning, motivating the players to learn by providing them a desirable gameplay experience is extremely important. However, it's not an easy task considering the quality of today's commercial non-educational games. Throughout the gameplay, the player should neither get overwhelmed nor under-challenged. The best way to do so is to monitor the player's actions in the game because these actions can tell the reason behind the player's performance. They can also tell about the player's lacking competencies or knowledge. Based on this information, in-game educational interventions in the form of hints can be provided to the player. The success of such games depends on their interactivity, motivational outlook and thus player retention. UNTANGLED is an online mapping game based on crowd-sourcing, developed by Reconfigurable Computing Lab, UNT for the mapping problem of CGRAs. It is also an educational game for teaching the concepts of reconfigurable computing. This thesis performs qualitative comparative analysis on gameplays of low performing players of UNTANGLED. And the implications of this analysis are used to provide recommendations for improving the gameplay experience for these players by guiding them. The recommendations include strategies to reach a high score and a compact solution, hints in the form of preset patterns and a clustering based approach.
Date: May 2017
Creator: Ambekar, Kiran

Reinforcing Variability Produces Stereotypic Behavior

Description: Behaving in novel ways is essential to the development of the types of complex performances described by the term creativity, problem solving, and perseverance. Some research suggests that response variability is an operant and a critical component of novel behavior. However, other account of novel behavior may be more parsimonious. Topographical variability has rarely been examined, nor has operant variability with organisms with baselines featuring stereotypic responding. This study examined the effects of a variability-specifying contingency on the cumulative novel responses of undergraduate students. Using the PORTL apparatus, participants interacted with a ball with a single hand. When the variability-specifying contingency was in effect, novel topographies were reinforced. When a reinforce every response condition was implemented, the participants did not emit any novel responses. When variability-specifying contingencies were in effect, novel responses were rarely followed by subsequent novel responses. They were mostly followed by repeated emission of the same topography, or by other previously emitted topographies. Novel responding did not persist long, although the variability-specifying contingency remained in effect and the potential for novel responding was great. The variability-specifying contingency often resulted in stereotypic response chains. Each of these findings call into the question the assertion that variability is an operant and suggests other possible explanations for the observed novelty.
Date: May 2017
Creator: Kieta, Andrew

The Struggling Dance: The Latino Journalist Experience Covering Hispanic and Latino Communities in Dallas

Description: This qualitative study addresses how the Dallas Morning News and Al Día reporters and editors determine what type of news related to the Dallas Latino and Hispanic communities gets covered. It also looks into how and why each newspaper tackles the coverage of these communities. Through a systematic analysis of 8 in-depth interviews and a 6-month ethnography, the findings of this study suggest that Latino and Hispanic journalists in Dallas feel the Latino and Hispanic communities are regarded as the "other." This study suggests the newsroom's hegemony and its news production routines influence the way Latino and Hispanic communities are covered in Dallas, and the way Latino and Hispanic reporters and editors who primarily cover these communities are treated. Though the newsrooms have made an effort to diversity its staff, reporters and editors claim they still have a long way to go before the staff accurately represents the large Hispanic and Latino population in the city.
Date: May 2017
Creator: Limon, Elvia

Sustainable Ecofriendly Insulation Foams for Disaster Relief Housing

Description: Natural disasters are affecting a significant number of people around the world. Sheltering is the first step in post-disaster activities towards the normalization of the affected people's lives. Temporary housing is being used in these cases until the construction of permanent houses are done. Disposal of temporary housing after use is leading to a significant environmental impact because most of them are filled with thermally insulative polymer foams that do not degrade in a short period. To reduce these problems this work proposes to use foams made with compostable thermoplastic polylactic acid (PLA) and degradable kenaf core as filler materials; these foams are made using CO2 as blowing agent for insulation purposes. Foams with PLA and 5%, 10% and 15% kenaf core were tested. Different properties and their relations were examined using differential scanning calorimetry (DSC), thermal conductivity, mechanical properties, scanning electron microscopy (SEM), x-ray μ-computed tomography (μ-CT) and building energy simulations were done using Energy Plus by NREL. The results show that mechanical properties are reduced with the introduction of kenaf core reinforcement while thermal conductivity display a noticeable improvement.
Date: May 2017
Creator: Chitela, Yuvaraj R

"That Every Christian May Be Suited": Isaac Watts's Hymns in the Writings of Early Mohegan Writers, Samson Occom and Joseph Johnson

Description: This thesis considers how Samson Occom and Joseph Johnson, Mohegan writers in Early America, used the hymns of English hymnodist, Isaac Watts. Each chapter traces how either Samson Occom or Joseph Johnson's adapted Isaac Watts's hymns for Native communities and how these texts are sites of affective sovereignty.
Date: May 2017
Creator: Ridley, Sarah Elizabeth

Third World Decolonization: The Pan Africanist Movement in the Age of Nasserism

Description: In the mid-twentieth century Egyptian President Gamal Abdel-Nasser, along with President Kwame Nkrumah of Ghana rose to international prominence as leaders and visionaries who were able to achieve political independence in their respective home countries while attempting to shape a destiny for Africa that did not involve Western imperialism. For Nasser's part, he first secured independence for Egypt, then turned his attention to the Middle East, but soon became as active in the politics of Sub Saharan Africa, also known as black Africa, as he was in the Arab world. This thesis explores Nasser's forays into Sub Saharan Africa during the period of decolonization on the continent and how his aspirations for Africa were equally a part of his political agenda that came to be known as Nasserism. Considering Nasser was the leader of the Third bloc, Egypt's fate was tied to Africa just as much as it was to the Middle East. Beyond the aspects of Nasser's involvement in Africa, this work also explores the active role Africans played in their quest for independence from European colonizers. Many African leaders during this time were as prominent and as shrewd as Nasser and were committed to establishing an anti-imperialist continent while developing modern African states based on the principles of Pan Africanism. While this occurred, new countries began to enter Africa and it became up to the African heads of state to determine how much involvement they wanted from these outsiders and at what cost. As these many dynamics played out in Africa, Pan Africanism was simultaneously occurring in the United States that linked black America's fate with Africa in movements that emphasized black nationalism and Third World political ideology.
Date: May 2017
Creator: Pendegraft, Gregory

Angular Analysis of a Wide-Band Energy Harvester based on Mutually Perpendicular Vibrating Piezoelectric Beams

Description: The recent advancements in electronics and the advents of small scaled instruments has increased the attachment of life and functionality of devices to electrical power sources but at the same time granted the engineers and companies the ability to use smaller sources of power and batteries. Therefore, many scientists have tried to come up with new solutions for a power alternatives. Piezoelectric is a promising material which can readily produce continuous electric power from mechanical inputs. However, their power output is dependent upon several factors such as, system natural frequency, their position in the system, the direction of vibration and many other internal and external factors. In this research the working bandwidth of the system is increased through utilizing of two different piezoelectric beam in different directions. The dependency of output power with respect to rotation angle and also the frequency shift due to the rotation angle is studied.
Date: December 2016
Creator: Mirzaabedini, Sohrab

Can Observing Behavior Predict Performance in Conditional Discriminations?

Description: Prompts are implemented often in training procedures, to include conditional discriminations, and this can lead to prompt dependency. The current study extends a prior study that suggested that the effectiveness of supplementary visual stimuli displaying the sample and comparison was dependent on the timing in relation to the selection task, presented as a prompt or feedback, in a match-to-sample procedure. The current research examines if the differences in that effectiveness were due to differences in observing behavior in those two conditions. Measures of observing behavior were determined by making access to the individual visual stimuli contingent on clicking on the visual stimulus and keeping the cursor located on the stimulus. Participants viewed the sample comparison much less than the comparison stimulus in both the prompt and feedback conditions. Latency to select the comparison stimulus was much shorter for the prompt condition suggesting that the participants might have interacted differently with the selection task in the two conditions.
Date: December 2016
Creator: Marchini, Kevin Julian

The Castle/Nikki Heat Phenomenon: A Detailed Examination of Female Representation in Entertainment Media

Description: As entertainment reflects a culture's ideology, it is important for researchers to study its messages and subsequently its potential meanings. Entertainment has the power to inform and persuade, creating models for behavior with which the public interacts. The entertainment texts for the purpose of this study are the Castle television series and the Nikki Heat novels. Together, they create a unique multi-layer fictional world. By using postmodern, feminist, communication, and entertainment theories, the results of this study provide a tightly focused lens which views a narrow aspect of entertainment media. Each text was thoroughly examined using textual analysis, Feminist Poststructuralist Discourse Analysis, and conversation analysis. Contrary to expectations, the results indicated that the Castle and Nikki Heat texts support hegemonic ideology, particularly through the use of exaggerated stereotypes, strict gender roles, imagery, and narrative choices that help perpetuate rape culture. The discussion outlines how these results can be interpreted through the dominant messages presented in the texts. This research is intended to serve as a foundation for future research regarding entertainment media.
Date: December 2016
Creator: Skinner, Katharine Virginia

Clocks and Mirrors

Description: The essays featured in this collection highlight the gaps, as well as parallels, between mental illness and the human condition. In "Appearances," the narrator struggles with her own visual identity especially after reflecting on her Mom's own lengthy history with the mirror. In "Migrations," the lyrical voice of the narrator carries the reader through the typical day of a clinically depressed female character. Lastly, "Attempting the Fall," addresses the issues society has with mental illness by following the narrator from her suicide attempt to the mental ward.
Date: December 2016
Creator: Thies, Jaclyn Michele

A Comparative Analysis of Digital and Paper Restaurant Menus Based on Customer Perception and Nutritional Labeling

Description: The restaurant industry is a highly customer-driven field. Therefore, it is imperative that restaurateurs consider customer expectations with regard to restaurant menus. The purpose of this experimental study is to examine the effects of menu format (i.e., paper or digital) and amount of nutritional information (i.e., extensive, brief, or none) on customer perceptions of the effectiveness, perceived ease of use, and information quality of the menu. Furthermore, this research intends to test the effect of these three menu attributes on the outcomes of value and satisfaction in order to assess the competitive advantage of one format over the other. The Cognitive Appraisal and Information Processing Theories provide structure to the proposed conceptual framework and give credence to the findings. This study also fills gaps in the present research by not only ameliorating weaknesses of extant studies, but also by examining several different aspects of restaurant menus simultaneously within a single study.
Date: December 2016
Creator: Moody, Bailey

Dissimilar Joining of Al (AA2139) – Mg (WE43) Alloys Using Friction Stir Welding

Description: This research demonstrates the use of friction stir welding (FSW) to join dissimilar (Al-Mg) metal alloys. The main challenges in joining different, dissimilar metal alloys is the formation of brittle intermetallic compounds (IMCs) in the stir zone affecting mechanical properties of joint significantly. In this present study, FSW joining process is used to join aluminum alloy AA2139 and magnesium alloy WE43. The 9.5 mm thick plates of AA2139 and WE43 were friction stir butt welded. Different processing parameters were used to optimize processing parameters. Also, various weldings showed a crack at interface due to formation of IMCs caused by liquation during FSW. A good strength sound weld was obtained using processing parameter of 1200 rev/min rotational speed; 76.2 mm/min traverse speed; 1.5 degree tilt and 0.13 mm offsets towards aluminum. The crack faded away as the tool was offset towards advancing side aluminum. Mostly, the research was focused on developing high strength joint through microstructural control to reduce IMCs thickness in Al-Mg dissimilar weld joint with optimized processing parameter and appropriate tool offset.
Date: December 2016
Creator: Poudel, Amir

Family and Cultural Influences on Latino Emerging Adults' Career Development

Description: There is an extensive amount of research on career development, but most of the constructs studied have focused on content-oriented variables rather than process-oriented variables. While some of the studies have examined samples from ethnic minority populations, the majority of studies use ethnic minority populations as comparison groups, studying between-group differences as opposed to within-group differences. The literature is especially deficient in the are of Latino career development. The current study will examine how family and culture influence the career development of Latino emerging adults. This study will explore the influence of socioeconomic status and acculturation on the career salience and career maturity of Latino emerging adults. The quality of the parent-emerging adult relationship will also be explored for its influence on career development outcomes in this population. One hundred fifty Latino undergraduate students ages 18-24 will be recruited for participation in this study. The participants will complete questionnaires regarding demographic information, acculturation, the quality of the parent-emerging adult relationship, career salience, and career maturity.
Date: December 2016
Creator: Rodriguez, Kristina

Memory and Continuity Amidst Irreversible Decline in the Texas Big Empty

Description: This thesis interrogates sense of place and place attachment in the Big Empty on the north central Texas plains. The region stretches from the Red River on the north to the Colorado River basin on the south and from the Cross Timbers on the east to the Caprock escarpment on the west. Since 1930, the Big Empty has seen sustained and severe population decline such that some counties there now register less than a quarter the population they did at their peaks during the interwar years. Through in-depth field interviews, I examine sense of place and place attachment amidst apparently irreversible decline. I also describe conditions of postindustrial rurality arising from rolling reconfigurations of economic and social relations, particularly changes in scale in farming and the diminished centrality of productivist agriculture in local economies and culture, and how these conditions become legible through the study of place.
Date: December 2016
Creator: Underwood, Robert Reed

Modeling of Hexagonal Boron Nitride Filled Bismalemide Polymer Composites for Thermal and Electrical Properties for Electronic Packaging

Description: Due to the multi-tasking and miniaturization of electronic devices, faster heat transfer is required from the device to avoid the thermal failure. Die-attached polymer adhesives are used to bond the chips in electronic packaging. These adhesives have to hold strong mechanical, thermal, dielectric, and moisture resistant properties. As polymers are insulators, heat conductive particles are inserted in it to enhance the thermal flow with an attention that there would be no electrical conductivity as well as no reduction in dielectric strength. This thesis focuses on the characterization of polymer nanocomposites for thermal and electrical properties with experimental and computational tools. Platelet geometry of hexagonal boron nitride offers highly anisotropic properties. Therefore, their alignment and degree of orientation offers tunable properties in polymer nanocomposites for thermal, electrical, and mechanical properties. This thesis intends to model the anisotropic behavior of thermal and dielectric properties using finite element and molecular dynamics simulations as well as experimental validation.
Date: December 2016
Creator: Uddin, Md Salah

Parcel-Based Change Detection Using Multi-Temporal LiDAR Data in the City of Surrey, British Columbia, Canada

Description: Change detection is amongst the most effective critical examination methods used in remote sensing technology. In this research, new methods are proposed for building and vegetation change detection using only LiDAR data without using any other remotely sensed data. Two LiDAR datasets from 2009 and 2013 will be used in this research. These datasets are provided by the City of Surrey. A Parcel map which shows parcels in the study area will be also used in this research because the objective of this research is detecting changes based on parcels. Different methods are applied to detect changes in buildings and vegetation respectively. Three attributes of object –slope, building volume, and building height are derived and used in this study. Changes in buildings are not only detected but also categorized based on their attributes. In addition, vegetation change detection is performed based on parcels. The output shows parcels with a change of vegetation. Accuracy assessment is done by using measures of completeness, correctness, and quality of extracted regions. Accuracy assessments suggest that building change detection is performed with better results.
Date: December 2016
Creator: Yigit, Aykut

Privacy Preserving EEG-based Authentication Using Perceptual Hashing

Description: The use of electroencephalogram (EEG), an electrophysiological monitoring method for recording the brain activity, for authentication has attracted the interest of researchers for over a decade. In addition to exhibiting qualities of biometric-based authentication, they are revocable, impossible to mimic, and resistant to coercion attacks. However, EEG signals carry a wealth of information about an individual and can reveal private information about the user. This brings significant privacy issues to EEG-based authentication systems as they have access to raw EEG signals. This thesis proposes a privacy-preserving EEG-based authentication system that preserves the privacy of the user by not revealing the raw EEG signals while allowing the system to authenticate the user accurately. In that, perceptual hashing is utilized and instead of raw EEG signals, their perceptually hashed values are used in the authentication process. In addition to describing the authentication process, algorithms to compute the perceptual hash are developed based on two feature extraction techniques. Experimental results show that an authentication system using perceptual hashing can achieve performance comparable to a system that has access to raw EEG signals if enough EEG channels are used in the process. This thesis also presents a security analysis to show that perceptual hashing can prevent information leakage.
Date: December 2016
Creator: Koppikar, Samir Dilip