Digital Commons Network^™

Effect Of Head Width, Head Height And Clamp Force On The Noise Reduction Provided By Two Different Styles Of Earmuffs, Jonathan R. Lewin

Graduate Theses, Dissertations, and Problem Reports (ETD)

Earmuffs provide necessary protection from the hazardous effects of noise for workers and the general population. The wearability and effectiveness of these devices is crucial for protection of hearing in noisy conditions. One component critical to the function of the earmuff is the clamp force that keeps the earmuff securely against the head and around the pinna. This clamp force must be high enough to provide a good seal, but not so high that it makes the muff uncomfortable. This study investigated the relationship between noise reduction (NR) and the force on the ear. This force was incrementally varied by …

Machine-Vision-Based Pose Estimation System Using Sensor Fusion For Autonomous Satellite Grappling, Andres Felipe Velasquez Escandon

Graduate Theses, Dissertations, and Problem Reports (ETD)

When capturing a non-cooperative satellite during an on-orbit satellite servicing mission, the position and orientation (pose) of the satellite with respect to the servicing vessel is required in order to guide the robotic arm of the vessel towards the satellite. The main objective of this research is the development of a machine vision-based pose estimation system for capturing a non-cooperative satellite. The proposed system finds the satellite pose using three types of natural geometric features: circles, lines and points, and it merges data from two monocular cameras and three different algorithms (one for each type of geometric feature) to increase …

Floc-Spanner: An O(1) Time, Locally Self-Stabilizing Algorithm For Geometric Spanner Construction In A Wireless Sensor Network, Goutham Ranganath

Graduate Theses, Dissertations, and Problem Reports (ETD)

Geometric spanners are a popular form of topology control in wireless networks because they yield an efficient, reduced interference subgraph for both unicast and broadcast routing.;In this thesis work a distributed algorithm for creation of geometric spanners in a wireless sensor network is presented. Given any connected network, we show that the algorithm terminates in O(1) time, irrespective of network size. Our algorithm uses an underlying clustering algorithm as a foundation for creating spanners, and only relies on the periodic heartbeat messages associated with cluster maintenance for the creation of the spanners. The algorithm is also shown to stabilize locally …

Wind And Wake Sensing With Uav Formation Flight: System Development And Flight Testing, Trenton Jameson Larrabee

Graduate Theses, Dissertations, and Problem Reports (ETD)

Wind turbulence including atmospheric turbulence and wake turbulence have been widely investigated; however, only recently it become possible to use Unmanned Aerial Vehicles (UAVs) as a validation tool for research in this area. Wind can be a major contributing factor of adverse weather for aircraft. More importantly, it is an even greater risk towards UAVs because of their small size and weight. Being able to estimate wind fields and gusts can potentially provide substantial benefits for both unmanned and manned aviation. Possible applications include gust suppression for improving handling qualities, a better warning system for high wind encounters, and enhanced …

Multiwavelength Studies Of Rotating Radio Transients, Joshua J. Miller

Graduate Theses, Dissertations, and Problem Reports (ETD)

Seven years ago, a new class of pulsars called the Rotating Radio Transients (RRATs) was discovered with the Parkes radio telescope in Australia (McLaughlin et al., 2006). These neutron stars are characterized by strong radio bursts at repeatable dispersion measures, but not detectable using standard periodicity-search algorithms. We now know of roughly 100 of these objects, discovered in new surveys and re-analysis of archival survey data. They generally have longer periods than those of the normal pulsar population, and several have high magnetic fields, similar to those other neutron star populations like the X-ray bright magnetars. However, some of the …

The Science Of Team Science: Exploring Principal Investigator Leadership Style And Team Collaboration Satisfaction, Stephenie K. Kennedy

Graduate Theses, Dissertations, and Problem Reports (ETD)

This study examined the relationship between the leadership style of principal investigators (PIs) of interdisciplinary research teams at academic health science centers and the collaboration satisfaction of their team members. Two stage sampling was used. One hundred NIH-funded principal investigators at eight regional health science centers completed a team identification form, identifying their teams as interdisciplinary and providing the names and emails of team members. An online survey instrument that included a basic demographic questionnaire, the Bolman and Deal Leadership (Others) Survey, and the Collaboration and Transdisciplinary Integration Survey was then sent to team members. The sample used for analysis …

Microfluidic Generated Egf-Gradients Induce Chemokinesis Of Transplantable Retinal Progenitor Cells Via The Jak/Stat And Pi3kinase Signaling Pathways, Uchenna J. Unachukwu, Moira Sauane, Maribel Vazquez, Stephen Redenti

Publications and Research

A growing number of studies are evaluating retinal progenitor cell (RPC) transplantation as an approach to repair retinal degeneration and restore visual function. To advance cell-replacement strategies for a practical retinal therapy, it is important to define the molecular and biochemical mechanisms guiding RPC motility. We have analyzed RPC expression of the epidermal growth factor receptor (EGFR) and evaluated whether exposure to epidermal growth factor (EGF) can coordinate motogenic activity in vitro. Using Boyden chamber analysis as an initial highthroughput screen, we determined that RPC motility was optimally stimulated by EGF concentrations in the range of 20-400ng/ml, with decreased stimulation …

Generations Apart: Exploring The Generation Gap In Theatre, Jesus Briones

Theses and Dissertations - UTB/UTPA

This thesis attempts to find relationships among three different ethnic groups (Jewish, Chinese, and Italian) presented in the following plays. First, there is an explanation of four different types of generation gaps that are discovered throughout the first play of examination, Fiddler on the Roof. There is a technology gap, a cultural gap, a religion gap, and an assimilation gap. Each of these gaps is present within Fiddler on the Roof and is varied throughout the remaining plays examined (Flower Drum Song and Over the River and Through the Woods). Each “gap” will be given an explanation and how it …

I,Metaboy, Mario Leal Jr.

Theses and Dissertations - UTB/UTPA

I,metaboy is a stage play about a young homosexual couple, one a soldier and the other a writer, during the wars in Iraq and Afghanistan in the 2000s and the struggles they encounter in their relationship when the soldier marries a woman to pass in the military. The story follows in the tradition of other Queer literatures that explore the state of the trope of the homosexual male within his given historical period. This historically places the identity. I,metaboy is based on an amalgamation of imagery from a variety of media (theatre, literature, TV, film, social policy, historical texts, myths, …

Graduation As A Function Of Attendance And Discipline Of Students In The Student Success Initiative Of Texas In One South Texas Urban School District, Maria Luisa Trevino-Guerra

Theses and Dissertations - UTB/UTPA

This study examined the trends and patterns across time of grade placement committee students on the dependent variable, graduation. Longitudinal data for independent variables, attendance and discipline was collected for 173 students from 2005 to 2013. The independent variables of attendance and discipline were examined to determine whether or not high school completion is dependent on these two measures.

The Grade 5 students of 2005-2006 in one south Texas large urban school district who were retained in the fifth grade or advanced to the next higher grade by the grade placement committee in accordance with the Student Success Initiative (SSI) …

Review Of Cerebral Aneurysm Formation, Growth, And Rupture., Nohra Chalouhi, Md, Brian L Hoh, David Hasan

Department of Neurosurgery Faculty Papers

No abstract provided.

Increasing Student Engagement In The Middle School Classroom, Elisa V. Biancalana

Dissertations

There is a need to improve student engagement in the middle school classroom. This change plan seeks to determine the level of student engagement in the classroom using the Instructional Practices Inventory tool. Classroom walkthroughs will be conducted to determine the level of engagement in the classroom. The data collected during the walkthroughs will drive the professional development needed for teachers in order to be able to implement teaching strategies that increase the level of student engagement in the classroom. The effective implementation of this change plan will ensure that teachers will work collaboratively in order to design engaging instruction …

X-Ray Fluorescence (Xrf) Analyzer - Theory, Utility, And Qa/Qc For Environmental And Commercial Product Samples In Cambodia, Sereyrath Lim

Multidisciplinary Studies Theses

Laboratory facilities in developed countries provide a variety of options for analysis of environmental samples and commercial commodities that could impact human health. The same is not true in developing countries and there is a great need to identify technologies that could be used to provide robust, accurate, cost-effective analysis that minimizes the need for extensive technical training. An X-ray Fluorescence (XRF) analyzer seems to be an analytical technique that could be such a tool for developing countries. Therefore, the objective of this thesis was to assess the performance and utility of a handheld, portable XRF unit in analyzing different …

Something To Talk About:Lessons Of Language And Literacy From A Tutorial Pilot Program, Joanna Neel

Education Faculty Publications and Presentations

This article describes a study conducted to determine evidence of key variables of literacy development and language acquisition, based on tutor’s lessons focusing on books and conversations about books and tutee’s questions. During one semester, university students tutored students from third to fifth grade, creating learning communities incorporating language and literate conversations, discussions about learning, and thinking/ comprehension strategies into each tutorial session, based on the needs of each student, as determined by the homeroom teacher. Conversations about books and topics were determined by student interest. Tutors were prepared with eight preparation sessions. Tutors noted student literacy behaviors in journals, …

Changes On Cran, Kurt Hornik, Achim Zeileis

The R Journal

New CRAN task views

New packages in CRAN task views

New contributed packages

Other changes

The R Journal (December 2013) 5(2): Complete Issue, The R Foundation

The R Journal

Editorial, Hadley Wickham

Contributed Research Articles

factorplot: Improving Presentation of Simple Contrasts in Generalized Linear Models, David A. Armstrong II

spMC: Modelling Spatial Random Fields with Continuous Lag Markov Chains, Luca Sartore

RNetCDF: A Package for Reading and Writing NetCDF Datasets, Pavel Michna and Milton Woods

Surface Melting Curve Analysis with R, Stefan Rödiger, Alexander Böhm and Ingolf Schimke

Performance Attribution for Equity Portfolios, Yang Lu and David Kane

ExactCIdiff: An R Package for Computing Exact Confidence Intervals for the Difference of Two Proportions, Guogen Shan and Weizhen Wang

rlme: An R Package for Rank-Based Estimation and Prediction in Random …

On Sampling From The Multivariate T Distribution, Marius Hofert

The R Journal

The multivariate normal and the multivariate t distributions belong to the most widely used multivariate distributions in statistics, quantitative risk management, and insurance. In contrast to the multivariate normal distribution, the parameterization of the multivariate t distribution does not correspond to its moments. This, paired with a non-standard implementation in the R package mvtnorm, provides traps for working with the multivariate t distribution. In this paper, common traps are clarified and corresponding recent changes to mvtnorm are presented.

Dynamic Parallelization Of R Functions, Stefan Böhringer

The R Journal

R offers several extension packages that allow it to perform parallel computations. These operate on fixed points in the program flow and make it difficult to deal with nested parallelism and to organize parallelism in complex computations in general. In this article we discuss, first, of how to detect parallelism in functions, and second, how to minimize user intervention in that process. We present a solution that requires minimal code changes and enables to flexibly and dynamically choose the degree of parallelization in the resulting computation. An implementation is provided by the R package parallelize.dynamic and practical issues are discussed …

Surface Melting Curve Analysis With R, Stefan Rödiger, Alexander Böhm, Ingolf Schimke

The R Journal

Nucleic acid Melting Curve Analysis is a powerful method to investigate the interaction of double stranded nucleic acids. Many researchers rely on closed source software which is not ubiquitously available, and gives only little control over the computation and data presentation. R in contrast, is open source, highly adaptable and provides numerous utilities for data import, sophisticated statistical analysis and presentation in publication quality. This article covers methods, implemented in the MBmca package, for DNA Melting Curve Analysis on microbead surfaces. Particularly, the use of the second derivative melting peaks is suggested as an additional parameter to characterize the melting …

Relationships Among Walleye Mercury, Selenium, Stable Isotopes, Size And Age, Mark J. Fincel, Robert P. Hanten, Shannon Minerich

The Prairie Naturalist

Bioaccumulation of mercury is well-documented in aquatic ecosystems and occurs as mercury is accumulated and passed up food chains (Kidd et al. 1995, Atwell et al. 1998, Downs et al. 1998). Trophic level correlations have been widely reported for mercury (Snodgrass et al. 2000) and other metals (Barron 1995). Generally, within a system, carnivores have the highest mercury loadings, omnivores intermediate and herbivores the lowest (Phillips et al. 1980). However, little research has focused on the differences in mercury bioaccumulation for a single species that ranges across multiple trophic levels (Burger et al. 2001).

Stable isotope analysis has expanded the …

Legislated Landscape: A Comparison Of New Deal Farm Communities In Hattiesburg, Mccomb, And Tupelo, Mississippi, Joy Delaine Rhoads

Master's Theses

Government New Deal farm policies of the 1930s changed the realities of farming and the landscape in Mississippi. This research endeavors to compare three farm communities created by New Deal legislation in the state: Hattiesburg, McComb, and Tupelo. The economic crisis that was the Great Depression created a highly politicized environment as citizens looked to the government for economic relief. A crisis this severe would require an exceptional effort to mitigate the economic hardships it created, in varying degrees, for millions of Americans. The actions of the federal government during the Great Depression were an interesting mix of paternalism, desperation, …

Nebraska Bird Review (December 2013) 81(4), Whole Issue

Nebraska Bird Review

Fall Field Report, August–November 2013 … 134

First Documented Record of Hooded Oriole (Icterus cucullatus) in Nebraska … 161

Hayden, Tristram, and a Pigeon from “Nebraska” … 165

Bridgeport Fall Field Days, September 20–22, 2013 ... 169

Index to Volume 81 ... 175

Subscription and Organization Information ... 187

A Study On Countermeasures Against Steganography: An Active Warden Approach, Qilin Qi

Department of Computer Electronics and Engineering: Dissertations, Theses, and Student Research

Digital steganography is a method used for hiding information in digital images. It can be used for secure communication. There have been many robust digital steganography methods invented in recent decades. The steganographic message can be inserted in multimedia cover signal such as audio, image and video. However, this technique also may be used by malicious users to transmit dangerous information through the Internet beyond the control of security agencies. How to detect and/or block potentially dangerous information transmission on the Internet through billions of multimedia files while not affecting innocent multimedia communications becomes a challenging problem. Existing steganalysis methods …

Kolsky Bar Experiment For High-Rate Large Deformations Of Polycarbonate, Jason G. Vogeler

Department of Engineering Mechanics: Dissertations, Theses, and Student Research

Polycarbonate (PC) is a tough, transparent engineering thermoplastic. Its impact strength and ability undergo large plastic deformations without shatter make PC an ideal protective material for impact-resilient eyewear, aircraft windows and transparent armor. A good understanding of the response of this material to large deformations at high strain rates is critical for its utilization in these applications. To this end, a striker-less Kolsky bar device is employed in this work for the needed material characterization. The apparatus allow impulsive torsion and/or compression loadings with pulse durations sufficiently long for the plastic flow behavior to develop fully. Three new testing techniques …

Kolsky Bar Experiment For High-Rate Large Deformations Of Polycarbonate, Jason Gerald Vogeler

Department of Engineering Mechanics: Dissertations, Theses, and Student Research

Polycarbonate (PC) is a tough, transparent engineering thermoplastic. Its impact strength and ability undergo large plastic deformations without shatter make PC an ideal protective material for impact-resilient eyewear, aircraft windows and transparent armor. A good understanding of the response of this material to large deformations at high strain rates is critical for its utilization in these applications. To this end, a striker-less Kolsky bar device is employed in this work for the needed material characterization. The apparatus allow impulsive torsion and/or compression loadings with pulse durations sufficiently long for the plastic flow behavior to develop fully. Three new testing techniques …

What Factors Impact The Effectiveness Of International Non Governmental Organizations (Ingos) In Ethiopia, Ermias Abraham

UNLV Theses, Dissertations, Professional Papers, and Capstones

Since the 1970s Ethiopia has experienced a massive increase of International Non-Governmental Organizations (INGOs) in its territory. The multiplication of these INGOs seems to be the result of the activities of both international donors and governments in Ethiopia. International donors considered INGOs as efficient, flexible or adoptive to the needs of the community and more trustworthy than government agencies in implementing development projects. International donors also believe that the proliferation of INGOs in Ethiopia will stimulate the growth of political democracy and trade liberalization. The government allowed the influx of these INGOs in order to tap the resources they bring …

Dehumanization: As It Is Present Within Bullying Behaviors In An Anti-Bullying Program, Katelyn Amos

UNLV Theses, Dissertations, Professional Papers, and Capstones

Bullying is an aggressive act performed repeatedly on another enacting a power differential. This thesis utilized data collected from The Anti-Bullying Prevention Pilot Program (ABPPP), which studied bullying within eleven schools in a large metropolitan area in southwestern United States. The program was aimed to increase positive school climate through the use of Operation Respect and Welcoming Schools programs.

Consensual Qualitative Research (CQR) and mixed methods approaches were used in order to analyze interviews and questionnaires. Grounded Theory analysis procedures were used to code the information, and thick descriptions were utilized to illustrate the occurrence of dehumanization among across four …

Max Operation In Statistical Static Timing Analysis On The Non-Gaussian Variation Sources For Vlsi Circuits, Abu M. Baker

UNLV Theses, Dissertations, Professional Papers, and Capstones

As CMOS technology continues to scale down, process variation introduces significant uncertainty in power and performance to VLSI circuits and significantly affects their reliability. If this uncertainty is not properly handled, it may become the bottleneck of CMOS technology improvement. As a result, deterministic analysis is no longer conservative and may result in either overestimation or underestimation of the circuit delay. As we know that Static-Timing Analysis (STA) is a deterministic way of computing the delay imposed by the circuits design and layout. It is based on a predetermined set of possible events of process variations, also called corners of …

Object Detection Using Contrast Enhancement And Dynamic Noise Reduction, Justin Lee Baker

UNLV Theses, Dissertations, Professional Papers, and Capstones

Edge detection is one of the most important steps a computer must perform to gain understanding of an object in a digital image either from disk or from video feed. Edge detection allows for the computer to describe the shape of the objects in an image and create a pixel boundary defining what is considered part of an object, and what is not. Cannys edge detection algorithm is one of the most robust and accurate of these edge detection algorithms. However, as with many algorithms in image processing, there are many cases where the algorithm does not perform as well …

Developing Ethical Competence: The Perspective Of Nurse Educators From Pre-Licensure Baccalaureate Nursing Programs Accredited By The Commission On Collegiate Nursing Education, Jennifer Lee Bartlett

UNLV Theses, Dissertations, Professional Papers, and Capstones

Nurses face ethically-charged situations every day, yet ethics education is not universally integrated into pre-licensure baccalaureate nursing programs. Like other forms of competence, ethical competence requires development. Nurse educators are poised to impact on the competence of their students, both defining the ethics content and designing students' exposure. The purpose of this study is to describe the concept of ethical competence from the perspective of baccalaureate nursing faculty and describe current methods of integration and evaluation of ethics education in pre-licensure baccalaureate nursing programs. This research will be conducted using a sequential (quantitative-qualitative) mixed method approach. The first phase of …