UNT Theses and Dissertations - 9,790 Matching Results

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Optimization of an SDR Based Aerial Base Station

Description: Most times people are unprepared to face natural disasters resulting in chaos, increased number of deaths, etc.Emergency responders need an efficiently working communication network to get in touch with the emergency services like hospitals, police, fire and rescue as well as people who are stranded. Such a network is also the need of the hour for survivors to contact their near and dear ones. One of the major barriers of communication during an emergency is the destruction of network elements. In case the communication devices survive the calamity, odds of the network getting congested are certainly high because almost everyone will be trying to use the same network resources. An important factor when dealing with emergency situations is the calls for an immediate response and an efficient Emergency Communication Systems (ECS). Currently there is a capability gap between existing ECS solutions and what we dream of achieving. Most current solutions do not meet cost or mobility constraints. An inexpensive, portable and mobile system will fulfill this capability gap. The main purpose of this research is to optimize the altitude and received signal strength of an aerial base station to provide maximum radio coverage on the ground as well as propose the best fit radio propagation channel model to carry out the experiment for the current scenario.
Date: August 2017
Creator: Mathews, Steffy Ann
Partner: UNT Libraries

A Place to Call Home: Uncovering the Housing Needs of Veterans

Description: When US veterans return home from serving their country reintegrating into civilian society is difficult. Adjustment is often associated with mental health stress and personal instability. One of the biggest predictors of successful reintegration is homeownership. The research is in partnership with Dallas Area Habitat for Humanity. The research seeks to explore the challenges veterans face when seeking homeownership.
Date: August 2017
Creator: Conrado, Ana Belen
Partner: UNT Libraries

A Preliminary Evaluation of an Indirect Assessment of Sensitivity to Aversive Stimulation

Description: Aversive tasks and activities are commonly encountered in the everyday routines of most individuals. For individuals with intellectual disabilities, a means to assess individual sensitivities to aversive stimulation could allow caregivers to avoid unnecessary contact with aversive events, teach appropriate ways to avoid or escape aversive situations, and condition tolerance to unavoidable aversive tasks and activities. The current study, conducted at a large, state-operated residential facility for adults with intellectual disabilities, used an anecdotal assessment, the Sensitivities to Aversive Stimulation Survey (SASS), to evaluate the relative aversiveness of an array of commonly encountered tasks and activities for each participant. Five caregivers complete the 25-question assessment, using Likert-type scales to rate individual participants' affect, compliance or tolerance, and severity of problem behavior related to each item. The mean scores of the raters were used to estimate the aversiveness of each task, condition, or activity. The outcomes from the SASS were then compared with outcomes of an experimental analysis in which participants could emit responses to escape situations that were ranked either high or low using the SASS. Relative aversiveness was evaluated by comparing the percentage of trials with escape behavior and duration of exposure for each stimulus. Preliminary results indicate that the SASS may be useful in identifying aversive tasks and stimuli.
Date: August 2017
Creator: Hope, Mariah L.
Partner: UNT Libraries

Quia Emptores, Subinfeudation, and the Decline of Feudalism in Medieval England

Description: The focus of this thesis is threefold. First, Edward I enacted the Statute of Westminster III, Quia Emptores in 1290, at the insistence of his leading barons. Secondly, there were precedents for the king of England doing something against his will. Finally, there were unintended consequences once parliament passed this statute. The passage of the statute effectively outlawed subinfeudation in all fee simple estates. It also detailed how land was able to be transferred from one possessor to another. Prior to this statute being signed into law, a lord owed the King feudal incidences, which are fees or services of various types, paid by each property holder. In some cases, these fees were due in the form of knights and fighting soldiers along with the weapons and armor to support them. The number of these knights owed depended on the amount of land held. Lords in many cases would transfer land to another person and that person would now owe the feudal incidences to his new lord, not the original one. This amount collected by the lord effectively reduced the payments to the original lord. During the early Middle Ages, feudal incidences began to change to a monetary exchange which would be used to purchase outside knights and soldiers. At this time, lords throughout England were losing revenue because of the subinfeudation. The Statute of Quia Emptores stopped subinfeudation and prevented lords from transferring land to another by any method except for subsitution. The statute itself was short but it covered all land in England. I will argue in my thesis that this statute had more to do with the ending of feudalism than any other single event. I will further argue that it was not King Edward I's intention to end feudalism. The ending of feudalism was an unintended ...
Date: August 2017
Creator: Garofalo, Michael
Partner: UNT Libraries

"Reality" while Dreaming in a Labyrinth: Christopher Nolan as Realist Auteur

Description: This thesis examines how the concept of an auteur (author of a film) has developed within contemporary Hollywood and popular culture. Building on concepts from Timothy Corrigan, this thesis adapts the ideas of the author and the commercial auteur to examine how director Christopher Nolan's name, and film work, has become branded as "realist" by the Hollywood film industry and by Nolan's consistent self-promotion. Through recurring signatures of "realism," such as, cinematic realism (immersive filmic techniques), technical realism (practical effects and actual locations), subjective realism (spectator access to a character's point of view), psychological realism (relatable motivations) and scientific realism (factual science), Nolan's work has become a recognizable and commoditized brand. Like many modern-day auteurs, Nolan himself has been used as a commodity to generate interest to his working methods and to appeal audiences to his studio films. Analyzing each of Christopher Nolan's films along with the industrial and cultural factors surrounding them, a method for understanding contemporary auteurism in Hollywood is presented. Through a consideration of extra-textual components, including promotional featurette's and journalistic interviews with Nolan, as well as his film crew, this thesis will explore how Nolan might be considered a template for a future of auteur branding.
Date: August 2017
Creator: Cowley, Brent
Partner: UNT Libraries

"Second Life, Second Chance"

Description: This is a collection of two stories, one fiction and one non-fiction, in communication with one another. Both stories explore how trauma can transform a life. In "Tabula Rasa," Mena is unable to recall her past after being beaten and left for dead. She must choose whether to uncover her past or forget it and move forward with her life. Set in a town run by witches, Mena learns that both choices are dangerous. In "Eternal Second," the narrator recounts the aftermath of her husband's suicide. She explores how trauma invades all aspects of her life. In both stories, women must navigate a new life created by the destruction of the old one.
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Date: August 2017
Creator: Beattie, Jessica Kathrine
Partner: UNT Libraries

Seismic Performance Evaluation of Novel Cold-Formed Steel Framed Shear Walls Sheathed with Corrugated Steel Sheets

Description: This thesis presents experiments and numerical analysis of a novel cold-formed steel framed shear wall sheathed with corrugated steel sheets. The objective of this newly designed shear wall is to meet the growing demand of mid-rise buildings and the combustibility requirement in the International Building Code. The strength of the novel shear wall is higher than currently code certified shear wall in AISI S400-15 so that it could be more favorable for mid-rise building in areas that are prone to earthquakes and hurricanes. Full-scale monotonic and cyclic tests were conducted on bearing walls and shear walls under combined lateral and gravity loads. Though the gravity loads had negative effects on the strength and stiffness of the shear wall due to the buckling of the chord framing members, it still shows promise to be used in mid-rise buildings. The objective of numerical analysis is to quantify the seismic performance factors of the newly design shear wall lateral-force resisting system by using the recommended methodology in FEMA P695. Two groups of building archetypes, story varied from two to five, were simulated in OpenSees program. Nonlinear static and dynamic analysis were performed in both horizontal directions of each building archetype. Finally, the results of the performance evaluation verified the seismic performance factors(R=Cd=6.5 and Ω =3.0) were appropriate for the novel shear wall system.
Date: August 2017
Creator: Lan, Xing
Partner: UNT Libraries

Synthesis and Application of New Chiral Ligands for Enantioselectivity Tuning in Transition Metal Catalysis

Description: A set of five new C3-symmetric phosphites were synthesized and tested in palladium-catalyzed asymmetric Suzuki coupling. The observed reactivity and selectivity were dependent upon several factors. One of the phosphites was able to achieve some of the highest levels of enantioselectivity in asymmetric Suzuki couplings with specific substrates. Different hypotheses have been made for understanding the ligand effects and reaction selectivities, and those hypotheses were tested via various methods including DOSY NMR experiments, X-ray crystallography, and correlation of catalyst selectivity with Tolman cone angles. Although only modest enantioselectivities were observed in most reactions, the ability to synthesis these phosphites in only three steps on gram scales and to readily tune their properties by simple modification of the binaphthyl 2´-substituents makes them promising candidates for determining structure-selectivity relationships in asymmetric transition metal catalysis, in which phosphites have been previously shown to be successful. A series of novel chiral oxazoline-based carbodicarbene ligands was targeted for synthesis. Unfortunately, the chosen synthetic route could not be completed due to unwanted reactivity of the oxazoline ring. However, a new and efficient route for Pd-catalyzed direct amination of aryl halides with oxazoline amine was developed and optimized during these studies. Chiral binaphthyl based Pd(II) ADC complexes with different substituent groups have been synthesized and tested in asymmetric Suzuki coupling reactions. Although only low enantioselectivities were observed in Suzuki coupling, this represents a new class of chiral metal-ADC catalysts that could be tested in further catalytic.
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Date: August 2017
Creator: Kong, Fanji
Partner: UNT Libraries

Teaching Behavior Professionals to Use the Interview-Informed Synthesized Contingency Analysis (IISCA): A Preliminary Investigation

Description: We assessed the implementation accuracy and fidelity of two board certified behavior analysts (BCBAs) using the open-ended interview from Hanley. Participants interviewed a confederate using the open-ended interview, and were then asked to use information gathered from the interview to create operational definitions of target behaviors as well as test and control condition procedures for a subsequent matched test-control functional analysis as is characteristic of the interview-informed synthesized contingency analysis (IISCA) strategy. Brief behavioral skills training (BST) was then implemented with all participants to increase the accuracy of constructing both target behavior definitions and functional analysis procedures. Preliminary results show moderate rates of accuracy of target behavior definitions and functional analysis procedures prior to BST, and high rates of accuracy following BST. The results also suggest high implementation fidelity on the open-ended interview may not be necessary to achieve high accuracy when constructing target behavior definitions and functional analysis procedures.
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Date: August 2017
Creator: Metras, Rachel
Partner: UNT Libraries

Two-Phase Spray Cooling with HFC-134a and HFO-1234yf for Thermal Management of Automotive Power Electronics using Practical Enhanced Surfaces

Description: The objective of this research was to investigate the performance of two-phase spray cooling with HFC-134a and HFO-1234yf refrigerants using practical enhanced heat transfer surfaces. Results of the study were expected to provide a quantitative spray cooling performance comparison with working fluids representing the current and next-generation mobile air conditioning refrigerants, and demonstrate the feasibility of this approach as an alternative active cooling technology for the thermal management of high heat flux power electronics (i.e., IGBTs) in electric-drive vehicles. Potential benefits of two-phase spray cooling include achieving more efficient and reliable operation, as well as compact and lightweight system design that would lead to cost reduction. The experimental work involved testing of four different enhanced boiling surfaces in comparison to a plain reference surface, using a commercial pressure-atomizing spray nozzle at a range of liquid flow rates for each refrigerant to determine the spray cooling performance with respect to heat transfer coefficient (HTC) and critical heat flux (CHF). The heater surfaces were prepared using dual-stage electroplating, brush coating, sanding, and particle blasting, all featuring "practical" room temperature processes that do not require specialized equipment. Based on the obtained results, HFC-134a provided a better heat transfer performance through higher HTC and CHF values compared to HFO-1234yf at all tested surfaces and flow rates. While majority of the tested surfaces provided comparable HTC and modestly higher CHF values compared to the reference surface, one of the enhanced surfaces offered significant heat transfer enhancement.
Date: August 2017
Creator: Altalidi, Sulaiman Saleh
Partner: UNT Libraries

A Woman's Place is at Work: The Rise of Women's Paid Labor in Five Texas Cities, 1900-1940

Description: This thesis is a quantitative analysis of women working for pay aged sixteen and older in five mid-size Texas cities from 1900 to 1940. It examines wage-earning women primarily in terms of race, age, marital status, and occupation at each census year and how those key factors changed over time. This study investigates what, if any, trends occurred in the types of occupations open to women and the roles of race, age, and marital status in women working for pay in the first forty years of the 20th century.
Date: August 2017
Creator: Scott, Codee
Partner: UNT Libraries

Academic Stress in Student-Athletes

Description: Academic stress and the causes of such stress are subjects that are found in very few studies concerning student-athletes. Therefore, the purpose of this quantitative study is to determine how the following variables relate to academic stress and perceived stress either through correlations or differences--demographics, academic classification, major or field of study, athletic scholarship status, and season of sport (in- season/ out of season). An online questionnaire containing a Perceived Stress Scale and a Perception of Academic Stress scale were distributed to 151 student-athlete participants at a university in the southwest United States. The results indicated that biological sex has a significant relationship to perceived stress. No other variables were found significant to perceived stress or academic stress.
Date: May 2017
Creator: James, Christina
Partner: UNT Libraries

Adrenergic and Cholinergic Regulation of Cardiovascular Function in Embryonic Neotropic Cormorants (Phalacrocorax basilianus)

Description: Investigations of cholinergic and adrenergic tone on heart rate (fH) and mean arterial pressure (Pm) during embryonic development have been conducted on numerous avian species. While these investigations have documented that adrenergic tone, a continuous stimulation, on fH and Pm is vital to embryonic development in the birds studied to date, development of cholinergic tone on fH has been shown to vary even within species. Further, past studies have been bias to focus primarily on precocial species while altricial species remain poorly understood in this context. The goal of this investigation was to investigate the role of cholinergic and adrenergic tone on fH and Pm of an altricial species, the neotropic cormorant (P. brasilianus) to address this bias. The embryonic neotropic cormorant possesses B-and-a adrenergic tone on fH and Pm at 70% and 90% incubation while cholinergic tone on fH occurs at 90% incubation. This pattern of control is similar to that previously reported for several species of precocial birds suggesting the development of tonic cardiovascular regulation may be conserved across avian taxa.
Date: May 2017
Creator: Cummins, James B
Partner: UNT Libraries

Application of High Entropy Alloys in Stent Implants

Description: High entropy alloys (HEAs) are alloys with five or more principal elements. Due to these distinct concept of alloying, the HEA exhibits unique and superior properties. The outstanding properties of HEA includes higher strength/hardness, superior wear resistance, high temperature stability, higher fatigue life, good corrosion and oxidation resistance. Such characteristics of HEA has been significant interest leading to researches on these emerging field. Even though many works are done to understand the characteristic of these HEAs, very few works are made on how the HEAs can be applied for commercial uses. This work discusses the application of High entropy alloys in biomedical applications. The coronary heart disease, the leading cause of death in the United States kills more than 350,000 persons/year and it costs $108.9 billion for the nation each year in spite of significant advancements in medical care and public awareness. A cardiovascular disease affects heart or blood vessels (arteries, veins and capillaries) or both by blocking the blood flow. As a surgical interventions, stent implants are deployed to cure or ameliorate the disease. However, the high failure rate of stents has lead researchers to give special attention towards analyzing stent structure, materials and characteristics. Many works related to alternate material and/or design are carried out in recent time. This paper discusses the feasibility of CoCrFeNiMn and Al0.1CoCrFeNi HEAs in stent implant application. This work is based on the speculation that CoCrFeNiMn and Al0.1CoCrFeNi HEAs are biocompatible material. These HEAs are characterized to determine the microstructure and mechanical properties. Computational modeling and analysis were carried out on stent implant by applying CoCrFeNiMn and Al0.1CoCrFeNi HEAs as material to understand the structural behavior.
Date: May 2017
Creator: Alagarsamy, Karthik
Partner: UNT Libraries

Assessing Rainfall Interception by Urban Tree Canopies in Denton, Texas

Description: Rainfall interception is one mechanism by which tree canopies can reduce surface runoff in urban areas. The objectives of this research were to: 1) quantify rainfall interception by urban tree canopies, and 2) determine the influence of vegetation and microenvironmental factors on rainfall interception rates. In the city of Denton, Texas, 30 mature post oak (Quercus stellata) and blackjack oak (Quercus marilandica) trees were selected for study. Trees were assigned to one of three categories: clusters of trees on greenspace (CG), isolated trees on greenspace (IG), and isolated trees surrounded by pavement (IP). Throughfall (the volume of water that travels through the canopy and reaches the soil surface) collectors were placed beneath these trees and rainfall collectors were placed in nearby open areas. Throughfall and rainfall were collected daily from 19 March to 4 July. Interception was calculated as the difference between throughfall and gross rainfall. Over the study period, there were 27 days with measurable rainfall; daily rainfall ranged from 1-51 mm. Over the sampling period, rainfall interception for individual trees ranged from -10% to 49%, indicating high spatial variability in interception. Percent interception was highest for the CG treatment (22.7 ± 3.8 SE), intermediate for IG (27.4 ± 2.3 SE), and lowest for IP (9.1 ± 4.9 SE). Factors like wind exposure, wind-driven rain and overall tree health may help explain this variability. This research will contribute to our knowledge of hydrological fluxes in urban areas and the role of urban green infrastructure in stormwater runoff mitigation.
Date: May 2017
Creator: Edington, Patrick
Partner: UNT Libraries

Automated GUI Tests Generation for Android Apps Using Q-learning

Description: Mobile applications are growing in popularity and pose new problems in the area of software testing. In particular, mobile applications heavily depend upon user interactions and a dynamically changing environment of system events. In this thesis, we focus on user-driven events and use Q-learning, a reinforcement machine learning algorithm, to generate tests for Android applications under test (AUT). We implement a framework that automates the generation of GUI test cases by using our Q-learning approach and compare it to a uniform random (UR) implementation. A novel feature of our approach is that we generate user-driven event sequences through the GUI, without the source code or the model of the AUT. Hence, considerable amount of cost and time are saved by avoiding the need for model generation for generating the tests. Our results show that the systematic path exploration used by Q-learning results in higher average code coverage in comparison to the uniform random approach.
Date: May 2017
Creator: Koppula, Sreedevi
Partner: UNT Libraries

Bodies of Evidence: A Qualitative Analysis of the Lived Experiences of Female Central American and Mexican Asylum Seekers in Dallas

Description: This work addresses the experiences of female asylum seekers from Central and Mexico currently living in Dallas, TX. The main purpose is to analyze how these women engage in the gendered processes of both migrating to and accessing legal resources and protection within the United States. As the women move through male-dominated spaces in their home country, the borderlands, and the asylum court they must challenge the patriarchal institutions that attempt to silence their narratives and criminalize their bodies. Their physical wounds become evidence in the courtroom, while outside of the courtroom their movements are monitored and tracked through multiple mechanisms of state control: ankle monitors, detention centers, ICE check-ins. They face intersectional discrimination as they are targeted as both women and immigrants. However, these female asylum seekers are not victims. They constantly display agency as they represent themselves in court, find solace in their faith, and form community with each other.
Date: May 2017
Creator: Kober, Ryan Kylie
Partner: UNT Libraries

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.
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Date: May 2017
Creator: Bhalotiya, Anuj Arun
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Cardiovascular Response to a Behavioral Restraint Challenge: Urge Magnitude Influence in Men and Women

Description: Agtarap, Wright, Mlynski, Hammad, and Blackledge took an initial step in providing support for the predictive validity of a new conceptual analysis concerned with behavioral restraint, defined as active resistance against a behavioral impulse or urge. The current study was designed to partially replicate and extend findings from their study, employing a common film protocol and a procedure for inducing low- and high levels of fatigue. Analyses on key data indicated that the fatigue manipulation was ineffective. On the other hand, they supported the suggestion that behavioral restraint should be proportional to the strength of an urge being resisted so long as success is perceived as possible and worthwhile. Analyses also provided evidence of gender differences for this behavioral restraint task. Women showed relatively enhanced CV responses to my manipulation of urge magnitude, performed less well, rated the behavioral restraint challenge as harder, and rated success on the more difficult behavioral restraint task as more important. A broad indication is that men and women can differ in the strength of impulses they experience in response to stimulus presentations as well as in the importance they place on resisting the impulses.
Date: May 2017
Creator: Mlynski, Christopher
Partner: UNT Libraries

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.
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Date: May 2017
Creator: Malla, Tika Kumari
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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 ...
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Date: May 2017
Creator: Garrison, Seth Thomas
Partner: UNT Libraries

A Cognitive Radio Application through Opportunistic Spectrum Access

Description: In wireless communication systems, one of the most important resources being focused on all the researchers is spectrum. A cognitive radio (CR) system is one of the efficient ways to access the radio spectrum opportunistically, and efficiently use the available underutilized licensed spectrum. Spectrum utilization can be significantly enhanced by developing more applications with adopting CR technology. CR systems are implemented using a radio technology called software-defined radios (SDR). SDR provides a flexible and cost-effective solution to fulfil the requirements of end users. We can see a lot of innovations in Internet of Things (IoT) and increasing number of smart devices. Hence, a CR system application involving an IoT device is studied in this thesis. Opportunistic spectrum access involves two tasks of CR system: spectrum sensing and dynamic spectrum access. The functioning of the CR system is rest upon the spectrum sensing. There are different spectrum sensing techniques used to detect the spectrum holes and a few of them are discussed here in this thesis. The simplest and easiest to implement energy detection spectrum sensing technique is used here to implement the CR system. Dynamic spectrum access involves different models and strategies to access the spectrum. Amongst the available models, an interweave model is more challenging and is used in this thesis. Interweave model needs effective spectrum sensing before accessing the spectrum opportunistically. The system designed and simulated in this thesis is capable of transmitting an output from an IoT device using USRP and GNU radio through accessing the radio spectrum opportunistically.
Date: May 2017
Creator: Bhadane, Kunal Ashok Ashok
Partner: UNT Libraries

A Community Based Assessment: An Analysis of Community Based Tourism in Kalache and Hulgol, India

Description: This study incorporated a community based assessment with a focus on community based tourism in Kalache and Hulgol, India. Kalache and Hulgol are two agrarian based communities located in the environmentally significant region of the Western Ghats. Each of these communities has considered community based tourism as a means to reduce urban youth outmigration, to diversify economic resources, and to encourage the empowerment of women. The primary goals of this study were to understand the community issues and objectives, to determine the level of support for tourism development, to determine participant attitudes toward tourism, and to determine the obstacles to tourism development. The findings of this project address the complexity of operating in the tourism industry, the impacts of tourism, and the use of community based tourism models in support of sustainable tourism.
Date: May 2017
Creator: Schutz, Michael
Partner: UNT Libraries

A Comparative Evaluation of Matrix Training Arrangements

Description: A common goal of instructional techniques is to teach skills effectively and efficiently. Matrix training techniques are both effective and efficient as they allow for the emergence of untrained responding to novel stimulus arrangements, a phenomenon known as recombinative generalization. However, it is unclear which type of matrix arrangement best promotes recombinative generalization. The current study compared two common matrix training approaches, an overlapping (OV) design and a non-overlapping (NOV) design, with respect to arranging relations targeted for training. We conducted a replication evaluation of a Wilshire and Toussaint study, and taught two typically-developing preschoolers compound object-action labels in Spanish and used either an OV or NOV matrix training design. Results from both studies demonstrated the participant trained with an OV design produced recombinative generalization and participants trained with a NOV design produced significantly low levels of emergence or none at all. These results suggest that an OV matrix design facilitates recombinative generalization more effectively than a NOV design. Implications for instructional arrangements are discussed.
Date: May 2017
Creator: Cliett, Terra N
Partner: UNT Libraries