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Theses and Dissertations

Theses/Dissertations

2014

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Institution
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Qatari Foreign Policy And The Arab Spring: From Mediation To Intervention, Basma Mahmoud Eletreby Dec 2014

Qatari Foreign Policy And The Arab Spring: From Mediation To Intervention, Basma Mahmoud Eletreby

Theses and Dissertations

This thesis examines the controversial role that Qatar has been playing in the Arab Spring, specifically from 2011 to 2013. Evidently, Qatari foreign policy will be assessed to comprehend the power this small state has been gaining in Middle East politics in a region plagued by never ending manifestations of power struggles and turbulent developments. The case studies of Egypt, Libya and Syria in which Qatari foreign policy involvement deployed the same rationale will be investigated to examine the increasing involvement of Qatar in Middle East politics. It concludes that the foreign policy of Qatar was both opportunistic and pro-Islamist …

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National Vs. International Schools: Factors Influencing School Choice In Egypt; The Voices Of Parents And Students., Yasmine Alaa Khorshed Dec 2014

National Vs. International Schools: Factors Influencing School Choice In Egypt; The Voices Of Parents And Students., Yasmine Alaa Khorshed

Theses and Dissertations

There are many national and international schools in Cairo today, and every year lots of parents make educational choices for their children. Those choices are based on various factors. This research explores the factors that influence parents to select a certain school type and not the other. It is an initial step into school research as an attempt to help educators and administrators understand parents’ and students’ priorities, needs and expectations when choosing a school. The research questions are: (1) What are the most and least important factors that parents consider when choosing a national/ international school for their children? …

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Characterizing And Managing Intrusion Detection System (Ids) Alerts With Multi-Server/Multi-Priority Queuing Theory, Christopher C. Olsen Dec 2014

Characterizing And Managing Intrusion Detection System (Ids) Alerts With Multi-Server/Multi-Priority Queuing Theory, Christopher C. Olsen

Theses and Dissertations

The DoD sets forth an objective to employ an active cyber defense capability to prevent intrusions onto DoD networks and systems. Intrusion Detection Systems (IDS) are a critical part of network defense architectures, but their alerts can be difficult to manage. This research applies Queuing Theory to the management of IDS alerts, seeking to answer how analysts and priority schemes effect alert processing performance. To characterize the effect of these two variables on queue wait times, a MATLAB simulation was developed to allow parametric analysis under two scenarios. The first varies the number of analysts and the second varies the …

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Potential Energy Curves And Associated Line Shape Of Alkali-Metal And Noble-Gas Interactions, Larry A. Blank Dec 2014

Potential Energy Curves And Associated Line Shape Of Alkali-Metal And Noble-Gas Interactions, Larry A. Blank

Theses and Dissertations

Recent interest in optically-pumped alkali laser systems has prompted this study into the binary interaction potentials between species of alkali-metal and rare-gas atoms and the effects of the collision of these species on the alkali-metal atom absorption spectrum. Special attention is placed on the relationship of the interaction potentials and the resulting line shape. The X2Σ+1/2, A2π1/2, A2π3/2, and B2Σ+1/2 potential energy curves and associated dipole matrix elements are computed for M+ Ng at the spin-orbit multi-reference configuration interaction level, where M = …

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Exploring Individual Differences In Workload Assessment, Danielle K. Boeke Dec 2014

Exploring Individual Differences In Workload Assessment, Danielle K. Boeke

Theses and Dissertations

Air Force missions continue to increase in complexity often imposing higher levels of task load from cognitive tasks on the operators. This increased task load manifests itself in increased cognitive workload and potentially derogated performance. While cognitive workload has been studied for decades, recent advances in objective workload models and physiology monitoring have the potential to provide a more robust understanding of workload, potentially allowing systems to adaptively employ automation to maintain operator peak performance. The current research sought to provide insight into the relationship between subjective workload, task performance, objective workload, and select physiology measures. Analysis of an existing …

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Influences Of Display Design And Task Management Strategy On Situation Awareness, Performance, And Workload In Process Control Environments, James R. Bowden Dec 2014

Influences Of Display Design And Task Management Strategy On Situation Awareness, Performance, And Workload In Process Control Environments, James R. Bowden

Theses and Dissertations

Process control environments demand well informed high performing human monitors to maintain effectual control of multiple processes. Most research aims to satisfy this requirement through the evaluation of competing heuristic-based display design constructs. Contrary to that method, this study takes a novel approach by examining both factors internal and external to the human observer to identify where beneficial outcomes actually reside. External factors explore the underlying design construct attributes, while internal factors focus on the effect of operator task management strategy, age, and experience. Results from this study present several key findings relative to operator situation awareness, performance, and workload. …

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Terrain Referenced Navigation Using Sift Features In Lidar Range-Based Data, Matthew T. Leines Dec 2014

Terrain Referenced Navigation Using Sift Features In Lidar Range-Based Data, Matthew T. Leines

Theses and Dissertations

The use of GNSS in aiding navigation has become widespread in aircraft. The long term accuracy of INS are enhanced by frequent updates of the highly precise position estimations GNSS provide. Unfortunately, operational environments exist where constant signal or the requisite number of satellites are unavailable, significantly degraded, or intentionally denied. This thesis describes a novel algorithm that uses scanning LiDAR range data, computer vision features, and a reference database to generate aircraft position estimations to update drifting INS estimates. The algorithm uses a single calibrated scanning LiDAR to sample the range and angle to the ground as an aircraft …

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Multi-Objective Trajectory Optimization Of A Hypersonic Reconnaissance Vehicle With Temperature Constraints, Tadeusz J. Masternak Dec 2014

Multi-Objective Trajectory Optimization Of A Hypersonic Reconnaissance Vehicle With Temperature Constraints, Tadeusz J. Masternak

Theses and Dissertations

Temperature-constrained optimal trajectories for a scramjet-based hypersonic reconnaissance vehicle were generated by developing an optimal control formulation and solving it using a variable order Gauss-Radau quadrature collocation method. The vehicle was assumed to be an air-breathing reconnaissance aircraft that has specified takeoff/landing locations, airborne refueling constraints, specified no-fly zones, and specified targets for sensor data collections. The aircraft model included fight dynamics, aerodynamics, and thermal constraints. This model was incorporated into an optimal control formulation that includes constraints on both the vehicle as well as mission parameters, such as avoidance of no-fly zones and coverage of high-value targets. Optimal trajectories …

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Using Data Mining To Determine The Impact Continuity Of Care Has On The Air Force’S Healthcare System, David F. Wade Dec 2014

Using Data Mining To Determine The Impact Continuity Of Care Has On The Air Force’S Healthcare System, David F. Wade

Theses and Dissertations

Department of Defense (DoD) healthcare is one of the largest contributors to the DoD budget. In recent years, the cost of the DoD healthcare system has risen at an exponential rate. Much research has been conducted on the impacts that continuity of care has on both improving the quality of patient care and on reducing healthcare costs in the private sector. The DoD has attempted to take a similar approach with regards to healthcare continuity as a means to reduce healthcare costs. This research investigates whether continuity of care influences costs and a military member's availability to perform duties. Specifically, …

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Hot Streak Characterization In Serpentine Exhaust Nozzles, Darrell S. Crowe Dec 2014

Hot Streak Characterization In Serpentine Exhaust Nozzles, Darrell S. Crowe

Theses and Dissertations

Modern aircraft of the United States Air Force face increasingly demanding cost, weight, and survivability requirements. Serpentine exhaust nozzles within an embedded engine allow a weapon system to fulfill mission survivability requirements by providing denial of direct line-of-sight into the high-temperature components of the engine. Recently, aircraft have experienced material degradation and failure along the aft deck due to extreme thermal loading. Failure has occurred in specific regions along the aft deck where concentrations of hot gas have come in contact with the surface causing hot streaks. The prevention of these failures will be aided by the accurate prediction of …

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A Decision Analysis Framework For Evaluation Of Helmet Mounted Display Alternatives For Fighter Aircraft, Matthew R. Dansereau Dec 2014

A Decision Analysis Framework For Evaluation Of Helmet Mounted Display Alternatives For Fighter Aircraft, Matthew R. Dansereau

Theses and Dissertations

The promise of providing an intuitive and efficient information interface, while allowing the warfighter to perform other critical tasks such as targeting or aircraft control, has led to the growing popularity of Helmet Mounted Displays (HMDs) across the military landscape, especially combat aircraft. Though design and selection of competing systems is critical to optimized performance and safety, structured methods for the evaluation of HMDs are not often used in the acquisition community, leaving selection among alternative designs to the judgment of subject matter experts. However, technical decision-making has been shown to be flawed without the use of a structured decision …

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Cloud-Induced Uncertainty For Visual Navigation, Alyssa N. Gutierrez Dec 2014

Cloud-Induced Uncertainty For Visual Navigation, Alyssa N. Gutierrez

Theses and Dissertations

This research addresses the numerical distortion of features due to the presence of clouds in an image. The research aims to quantify the probability of a mismatch between two features in a single image, which will describe the likelihood that a visual navigation system incorrectly tracks a feature throughout an image sequence, leading to position miscalculations. First, an algorithm is developed for calculating transparency of clouds in images at the pixel level. The algorithm determines transparency based on the distance between each pixel color and the average pixel color of the clouds. The algorithm is used to create a dataset …

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Improving Non-Linear Approaches To Anomaly Detection, Class Separation, And Visualization, Todd J. Paciencia Dec 2014

Improving Non-Linear Approaches To Anomaly Detection, Class Separation, And Visualization, Todd J. Paciencia

Theses and Dissertations

Linear approaches for multivariate data analysis are popular due to their lower complexity, reduced computational time, and easier interpretation. In many cases, linear approaches produce adequate results; however, non-linear methods may generate more robust transformations, features, and decision boundaries. Of course, these nonlinear methods present their own unique challenges that often inhibit their use. In this research, improvements to existing non-linear techniques are investigated for the purposes of providing better, timely class separation and improved anomaly detection on various multivariate datasets, culminating in application to anomaly detection in hyperspectral imagery. Primarily, kernel-based methods are investigated, with some consideration towards other …

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Approximate Dynamic Programming For Military Resource Allocation, Carl R. Parson Dec 2014

Approximate Dynamic Programming For Military Resource Allocation, Carl R. Parson

Theses and Dissertations

This research considers the optimal allocation of weapons to a collection of targets with the objective of maximizing the value of destroyed targets. The weapon-target assignment (WTA) problem is a classic non-linear combinatorial optimization problem with an extensive history in operations research literature. The dynamic weapon target assignment (DWTA) problem aims to assign weapons optimally over time using the information gained to improve the outcome of their engagements. This research investigates various formulations of the DWTA problem and develops algorithms for their solution. Finally, an embedded optimization problem is introduced in which optimization of the multi-stage DWTA is used to …

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Optimal Collision Avoidance Trajectories For Unmanned/Remotely Piloted Aircraft, Nathan E. Smith Dec 2014

Optimal Collision Avoidance Trajectories For Unmanned/Remotely Piloted Aircraft, Nathan E. Smith

Theses and Dissertations

The post-911 environment has punctuated the force-multiplying capabilities that Remotely Piloted Aircraft (RPA) provides combatant commanders at all echelons on the battlefield. Not only have unmanned aircraft systems made near-revolutionary impacts on the battlefield, their utility and proliferation in law enforcement, homeland security, humanitarian operations, and commercial applications have likewise increased at a rapid rate. As such, under the Federal Aviation Administration (FAA) Modernization and Reform Act of 2012, the United States Congress tasked the FAA to provide for the safe integration of civil unmanned aircraft systems into the national airspace system (NAS) as soon as practicable, but not later …

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Beliefs, Practices, And Preservice Teachers: A Case Study, Janie Riddle Goodman Dec 2014

Beliefs, Practices, And Preservice Teachers: A Case Study, Janie Riddle Goodman

Theses and Dissertations

Existing in the chronology of content area literacy instruction is a convincing body of research that supports the role of strategic learning in students’ literacy development. However, much of what is known about teaching reading comprehension strategies is not part of the instruction found in many secondary classrooms. Even though studies have shown how students benefit from using comprehension strategies, the instructional necessities for teaching those strategies are not part of many secondary teachers’ practices. Additionally, the historical focus on literacy practices and strategies is shifting towards attention on the critical role of the disciplines in secondary literacy and the …

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Characterization Of Electrodeposited Copper Foil Surface Roughness For Accurate Conductor Power Loss Modeling, Michael B. Griesi Dec 2014

Characterization Of Electrodeposited Copper Foil Surface Roughness For Accurate Conductor Power Loss Modeling, Michael B. Griesi

Theses and Dissertations

As computer data rates have increased, designers observed that the standard models for estimating the impact of copper foil surface roughness on conductor loss are limited to a few GHz. The more recent snowball model (a “snowball” estimation of the Huray Model) has demonstrated improved conductor loss predictions up to 50 GHz by estimating the necessary parameters using reasonable assumptions about the geometric surface features of electrodeposited copper foil. Since then, the Huray Model has been incorporated into commercial electromagnetic field simulators. However, a standard method of characterizing the electrodeposited copper foil used in high-speed circuits to directly implement the …

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Surface Modification Of Nanoplatelets In Polymer Nanocomposites, Shailesh K. Shori Dec 2014

Surface Modification Of Nanoplatelets In Polymer Nanocomposites, Shailesh K. Shori

Theses and Dissertations

In polymer nanocomposites (PNCs), it is very important that the nanofiller (typically an inorganic) is well-dispersed in an organic polymer matrix. Optimal compatibility results in end-use products such as packaging materials with enhanced properties. In practice, however, this is challenging to achieve because “ideal” dispersions require the complete uniform separation, termed exfoliation, of the nanofiller within the matrix. As a result, different nanofillers including calcium niobate (CN) and montmorillonite (MMT) are first studied for their ability to exfoliate in aqueous suspensions by measuring the organic cation uptake. The cation exchange capacity, or CEC, determined that CN needs further work before …

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Compositional Traits In Sorghum Bicolor Characterized By Transcriptome, Ionome And Genome-Wide Association Analysis, Nadia Shakoor Dec 2014

Compositional Traits In Sorghum Bicolor Characterized By Transcriptome, Ionome And Genome-Wide Association Analysis, Nadia Shakoor

Theses and Dissertations

To address the challenge of global mineral malnutrition, current biofortification research in crop plants aims to improve mineral concentration and micronutrient bioavailablity via genetic and traditional breeding methods. Many staple food crops are also used as biofuels, and the chemical and mineral composition of these energy crops directly affect biomass quality and subsequent energy output. Identification of genes and QTL that impact mineral and compositional traits in the grain and biomass of major cereals, including sorghum, is fundamental to developing breeding and selection methods aimed at increasing bioavailable minerals and improving biofuel suitability and seed nutritional quality. A combinatorial strategy …

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Simulation Based Evaluation Of Multiscale Small Area Health Models, Purbasha Dasgupta Dec 2014

Simulation Based Evaluation Of Multiscale Small Area Health Models, Purbasha Dasgupta

Theses and Dissertations

The effects of scale on the analysis of spatial data, often referred to as the modifiable areal unit problem in spatial studies, is one of the issues often encountered in small area health models. These spatial effects of scale are also seen in the areas of disease mapping where data are usually available in counts. Often there is a need to consider the different scales of aggregation that exist within count data, since inferences based on analyses can vary if we change the definition of the unit of analysis. This thesis provides a framework that describes the distribution of relative …

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School-Based Sexuality Education, Gender, And Relationship Self-Efficacy: A Moderated-Mediation Analysis Of Sexual Behavior In First-Year College Students, Sara C. Schmidt Dec 2014

School-Based Sexuality Education, Gender, And Relationship Self-Efficacy: A Moderated-Mediation Analysis Of Sexual Behavior In First-Year College Students, Sara C. Schmidt

Theses and Dissertations

While the effectiveness at abstinence-only versus comprehensive sexuality education in preventing adolescent risky sexual behavior is widely researched, little is known about whether material learned in secondary school sexuality education classes impacts emerging adult sexual behavior in the college environment. Furthermore, research suggests that self-efficacy – or beliefs in one’s abilities to organize and execute actions – may be more critical than knowledge or skills in terms of how individuals enact behavior. We hypothesized a moderated-mediation effect by which the causal impact of type of sexuality education on four different sexual behaviors during the first year in college is transmitted …

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Examining The Influence Of Healthy Eating Identity On Shopping Behaviors, Jordan Brittingham Dec 2014

Examining The Influence Of Healthy Eating Identity On Shopping Behaviors, Jordan Brittingham

Theses and Dissertations

Eating identity is shown to be a promising measure capable of enhancing our understanding of nutrition behavior. Persons with healthy eating identities are less likely to consume the typical American diet and report healthier diets in general. While there are several studies linking healthy eating identity and diet, there is currently no research examining healthy eating identity in relation to food shopping behavior, an important aspect of nutritional intake. The purpose of this study was to examine the influence of healthy eating identity on shopping behaviors including supermarket utilization, supercenter utilization, likelihood of shopping at the nearest store, distance to …

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Marine Population Connectivity: Range Boundaries And Climate Change, Rhiannon Leigh Rognstad Dec 2014

Marine Population Connectivity: Range Boundaries And Climate Change, Rhiannon Leigh Rognstad

Theses and Dissertations

Population connectivity, particularly in open systems, is an important metric for understanding population-level processes on both ecological and evolutionary timescales. In coastal marine systems, adults are typically sedentary and dispersal occurs primarily during a larval stage when individuals are transported in ocean currents. Because coastal marine populations exist as networks of interconnected subpopulations, variation in the magnitude and extent of population connectivity can have profound effects on population dynamics and species distribution limits. Connectivity is a complex process, affected by a multitude of factors, including adult inputs and physical dispersal, which operate at multiple scales and may interact. This dissertation …

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The Role Of The Learning Community In The Professional Development Of Literacy Teachers, Abbey Spoonmore Duggins Dec 2014

The Role Of The Learning Community In The Professional Development Of Literacy Teachers, Abbey Spoonmore Duggins

Theses and Dissertations

This qualitative case study explored a learning community in action. The purpose of this study was to investigate the professional conversations that teachers in a learning community had and the impact of those conversations on the practices and beliefs of the individual teachers in the community. Specifically, the study sought to discover how and why facets of professional learning transferred (or did not transfer) into classroom practice. The researcher spent five months with a learning community comprised of six middle school literacy teachers and attended their learning community meetings, visited their classrooms, and videotaped them teaching. Each classroom visit was …

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Quality Improvement Project: A Comparison Of Daily Routine Chest Radiography Versus Clinically-Indicated Chest Radiography In Preventing Ventilator-Associated Pneumonia In Adult Icu Patients On Ventilators: An Evidenced Based Practice Project, Kimberly Mckenney Dec 2014

Quality Improvement Project: A Comparison Of Daily Routine Chest Radiography Versus Clinically-Indicated Chest Radiography In Preventing Ventilator-Associated Pneumonia In Adult Icu Patients On Ventilators: An Evidenced Based Practice Project, Kimberly Mckenney

Theses and Dissertations

Ventilator-associated pneumonia is one of the critical complications identified by a chest x-ray (CXR). However, there is a controversy about the use of CXRs. Overuse of the CXR has also identified concern among the ICU patient population. The purpose of this evidenced-based practice project was to determine if there were differences in patient outcomes when receiving daily routine CXRs as compared to clinically-indicated CXRs. Patient outcomes measured were: ICU length of stay, complications while on the ventilator and ICU mortality, number of ventilator days, diagnostic efficacy, therapeutic efficacy, costs, and radiation exposure The author identified 30 articles in the search …

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Independence At Large: Contemporary China's Alternative Music Scenes And The Cultural Practices Of Post-Socialist Urban Youth, Shan Huang Dec 2014

Independence At Large: Contemporary China's Alternative Music Scenes And The Cultural Practices Of Post-Socialist Urban Youth, Shan Huang

Theses and Dissertations

Using contemporary Beijing’s alternative music scenes as a focal point, this ethnographic research seeks to enrich the understanding of China’s post-socialist urban youth by examining their cultural practices. First, this thesis offers an analytical account of the popularizing embrace of “independent cultures,” which is defined as a collection of experienceable objects and activities in musical, filmic, theatric, and other cultural forms that are well recognized yet believed by advocates as having aesthetic and participatory features that are different from those produced in the popular culture industry. While the vogue for independent cultures is substantially conditioned by the socioeconomic attributes of …

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Thermal Ecology And Physiology Of An Intertidal Predator-Prey System: Pisaster Ochraceus And Mytilus Californianus, Cristian J. Monaco Dec 2014

Thermal Ecology And Physiology Of An Intertidal Predator-Prey System: Pisaster Ochraceus And Mytilus Californianus, Cristian J. Monaco

Theses and Dissertations

Untangling natural systems’ complexity requires understanding the mechanisms responsible for organisms’ responses to environmental change. Recently, significant advances have been made by recognizing the relevance of direct and indirect effects, which take place when multiple biotic and abiotic factors influence each other. I examined potential direct effects of environmental variables on a predator-prey interaction, as well as potential indirect effects of these variables on the interaction itself. I placed emphasis on behavioral and physiological adaptations, which would potentially contribute/modify these effects. My study system was comprised of a rocky intertidal keystone predator, the sea star Pisaster ochraceus, and its main …

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Effects Of Sight Singing Using Moveable-Do Solmization On The Transposition Performance Of Undergraduate Group Piano Students, Michelle Irene Wachter Dec 2014

Effects Of Sight Singing Using Moveable-Do Solmization On The Transposition Performance Of Undergraduate Group Piano Students, Michelle Irene Wachter

Theses and Dissertations

The purpose of this study was to examine the effects of sight singing, using moveable-do solmization, on the keyboard transposition performance of undergraduate group piano students. Thirty-nine (N = 39) undergraduate non-keyboard music majors enrolled in three intact sections of first-semester group piano courses participated in this quantitative study. Students completed an individual pretest and posttest consisting of a videotaped sight-reading and transposition performance and a pretest and posttest questionnaire. Throughout the six-week treatment period, all students received sight-reading and transposition instruction using identical musical examples. A control group sight read and transposed examples without singing, while students in two …

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A Phenomenological Study Of Student Engagement In United States History Classrooms, Emily Louvette Manigault Dec 2014

A Phenomenological Study Of Student Engagement In United States History Classrooms, Emily Louvette Manigault

Theses and Dissertations

The purpose of this phenomenological study is to explore the relationship between student engagement and the perception of academic achievement (learning) by teachers and students in an urban high school social studies course. Over the past several years, educational leaders and researchers have tried to find a cause for a number of issues in public education, including low academic achievement, increasing student drop-out rates and the decline of positive perceptions of schools in general. As a result, there has been increasing research done on the level of engagement that students experience during their schooling. Much of the research has focused …

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Experimental And Theoretical Studies Of Native And Engineered Vascular Tissue Mechanics, Boran Zhou Dec 2014

Experimental And Theoretical Studies Of Native And Engineered Vascular Tissue Mechanics, Boran Zhou

Theses and Dissertations

Background: Implantation of vascular grafts provides a means to restore blood flow in compromised regions of the circulatory system, and thus is used to treat a wide range of cardiovascular diseases. Despite significant advancements in autologous grafting strategies as well as the engineering of synthetic alternatives, mechanical, structural, and compositional incongruities between the graft and the host artery remain as contributing factors to graft failure. The typical failure modality manifests as proximal anastomotic intimal hyperplasia, which places restrictions on the host vessel size currently treated with grafting strategies (> 5 mm internal diameter). In order to improve long-term clinical outcomes, …

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