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Quantum Dot Band Gap Investigations, John Ryan Peterson Nov 2016

Quantum Dot Band Gap Investigations, John Ryan Peterson

Student Works

Improving solar panel efficiency has become increasingly important as the world searches for cheap renewable energy. Recent developments in the industry have focused on multi-layer cells, some of which use semiconducting dyes to absorb light in place of crystalline solids. In this paper, I characterize various dyes recently synthesized for use in solar panels. These dyes contain semiconducting nanoparticles enclosed primarily by the protein ferritin to limit particle size. The band gaps were measured using either optical absorption spectroscopy or measuring the photoluminescence spectrum, depending on the type of semiconductor. The results indicate that both manganese oxide and lead sulfide …


Material Selection Shape Factors For Compliant Arrays In Bending, David T. Fullwood, Todd G. Nelson, Jared T. Bruton, Nathan E. Rieske, M. Patrick Walton, Larry L. Howell Nov 2016

Material Selection Shape Factors For Compliant Arrays In Bending, David T. Fullwood, Todd G. Nelson, Jared T. Bruton, Nathan E. Rieske, M. Patrick Walton, Larry L. Howell

Faculty Publications

Similar to the general class of metamaterials, compliant arrays (CAs) are engineered from an array of subelements that combine to produce a response that is typically not available from a at panel made of a single material. As such, analysis and design of CA systems requires the integration of both the material and geometrical properties of the array. This paper proposes a convenient and efficient method of combining these essential elements using analytically derived shape factors for bending modes. The approach is validated experimentally, and used to demonstrate large regions of previously inaccessible property combinations in material selection charts that …


Towards Using Certificate-Based Authentication As A Defense Against Evil Twins In 802.11 Networks, Travis S. Hendershot Nov 2016

Towards Using Certificate-Based Authentication As A Defense Against Evil Twins In 802.11 Networks, Travis S. Hendershot

Theses and Dissertations

Wireless clients are vulnerable to exploitation by evil twins due to flaws in the authentication process of 802.11 Wi-Fi networks. Current certificate-based wireless authentication protocols present a potential solution, but are limited in their ability to provide a secure and usable platform for certificate validation. Our work seeks to mitigate these limitations by exploring a client-side strategy for utilizing alternative trust models in wireless network authentication. We compile a taxonomy of various trust models for conducting certificate-based authentication of wireless networks and methodically evaluate each model according to desirable properties of security, usability, and deployability. We then build a platform …


Geochemical Comparison Of Ancient And Modern Eolian Dune Foresets Using Principal Components Analysis, David A. Little Nov 2016

Geochemical Comparison Of Ancient And Modern Eolian Dune Foresets Using Principal Components Analysis, David A. Little

Theses and Dissertations

Geochemistry has been used to determine the provenance and diagenetic history of eolian sandstone deposits. However, the grain size, sorting, cementation, and detrital composition of eolian units can change along dune foreset laminae. The purpose of this study was to test for consistent trends of compositional change along dune foresets. Such trends could increase the quality of geochemical sampling of eolian sandstones and possibly aid in estimating the original height of ancient sand dunes. XRF data was gathered for both major and trace elements from the Pennsylvanian to Permian Weber Sandstone, Early Jurassic Navajo Sandstone, and modern Coral Pink Sand …


A Common Misconception In Multi-Label Learning, Michael Benjamin Brodie Nov 2016

A Common Misconception In Multi-Label Learning, Michael Benjamin Brodie

Theses and Dissertations

The majority of current multi-label classification research focuses on learning dependency structures among output labels. This paper provides a novel theoretical view on the purported assumption that effective multi-label classification models must exploit output dependencies. We submit that the flurry of recent dependency-exploiting, multi-label algorithms may stem from the deficiencies in existing datasets, rather than an inherent need to better model dependencies. We introduce a novel categorization of multi-label metrics, namely, evenly and unevenly weighted label metrics. We explore specific features that predispose datasets to improved classification by methods that model label dependence. Additionally, we provide an empirical analysis of …


Creativity & Religion: A Self-Study Of Mormon Mindset In The Art Classroom, Shon Scot Feller Nov 2016

Creativity & Religion: A Self-Study Of Mormon Mindset In The Art Classroom, Shon Scot Feller

Theses and Dissertations

A high school art teacher investigates the relationship of his religious beliefs with his notions of what it means to be creative. This Mormon teacher examines his religious and experiential life through self-study, by drawing from autoethnographic and hermeneutic phenomenological strategies. He believes that everyone, including himself and his students, has a creative potential. He also analyzes how his Mormon religion affects his view of creativity and how creativity has affected his behavior as a Mormon. The conclusions he reaches uncover the need for balance between his creative self and his Mormon self and outlines several ways to merge these …


Notes Oct 2016

Notes

Comparative Civilizations Review

No abstract provided.


Technology In Eurasia Before Modern Times: A Survey, Norman C. Rothman Oct 2016

Technology In Eurasia Before Modern Times: A Survey, Norman C. Rothman

Comparative Civilizations Review

This work traces the development of technology in Eurasia before 1400 C.E. It covers the Middle East, China, India, and Europe. It puts the emphasis on such key areas as metallurgy and textiles as well as the development of inventions and innovations in the technological and applied scientific processes. Simultaneously, it examines the role that trade, urbanization, governmental policy, and cultural imperatives played in this process. Chronologically, it covers the ancient, classical, and medieval period periods. It includes a brief introduction dealing with definitions and ends with a general conclusion.


Interview With Scott Russell Sanders Oct 2016

Interview With Scott Russell Sanders

Inscape

No abstract provided.


The Seto Collection In The Ubc Asian Library: Its Usefulness To Scholars And Students, Jing Liu, Allan Cho, Phoebe Chow Oct 2016

The Seto Collection In The Ubc Asian Library: Its Usefulness To Scholars And Students, Jing Liu, Allan Cho, Phoebe Chow

Journal of East Asian Libraries

No abstract provided.


The State Of Man-In-The-Middle Tls Proxies: Prevalence And User Attitudes, Mark Thomas Oneill Oct 2016

The State Of Man-In-The-Middle Tls Proxies: Prevalence And User Attitudes, Mark Thomas Oneill

Theses and Dissertations

We measure the prevalence and uses of Man-in-the-Middle TLS proxies using a Flash tool deployed with a Google AdWords campaign. We generate 15.2 million certificate tests across two large-scale measurement studies and find that 1 in 250 TLS connections are intercepted by proxies. The majority of these proxies appear to be benevolent, however we identify over 3,600 cases where eight malware products are using this technology nefariously. We also find thousands of instances of negligent, duplicitous, and suspicious behavior, some of which degrade security for users without their knowledge. Distinguishing these types of practices is challenging in practice, indicating a …


Peering Through The Cloud—Investigating The Perceptions And Behaviors Of Cloud Storage Users, Justin Chun Wu Oct 2016

Peering Through The Cloud—Investigating The Perceptions And Behaviors Of Cloud Storage Users, Justin Chun Wu

Theses and Dissertations

We present the results of a survey and interviews focused on user perceptions and behaviors with respect to cloud storage services. In particular, we study behaviors such as which services are used, what types of data are stored, and how collaboration and sharing are performed. We also investigate user attitudes toward cloud storage on topics such as payment, privacy, security, and robustness. We find that users are drawn to cloud storage because it enables robust, ubiquitous access to their files, as well as enabling sharing and collaborative efforts. However, users' preferred medium for file sharing continues to be email, due …


Teachers' Adoption Of Learner-Centered Technology, Melissa C. Warr Oct 2016

Teachers' Adoption Of Learner-Centered Technology, Melissa C. Warr

Theses and Dissertations

In this thesis, I describe research on teachers' experiences with learner-centered technology. Specifically, this research investigated teachers' experiences with adoption of the learner-centered tools available from Imagine Learning, an online elementary school literacy program. This thesis includes an extended literature review describing learner-centered classrooms, technology integration, and models of technology adoption, followed by a journal-ready article that describes teachers' experiences throughout the process of adopting Imagine Learning. Finally, I provide a description my experiences throughout this project as well as a proposal for future areas of study.


Verification Of Task Parallel Programs Using Predictive Analysis, Radha Vi Nakade Oct 2016

Verification Of Task Parallel Programs Using Predictive Analysis, Radha Vi Nakade

Theses and Dissertations

Task parallel programming languages provide a way for creating asynchronous tasks that can run concurrently. The advantage of using task parallelism is that the programmer can write code that is independent of the underlying hardware. The runtime determines the number of processor cores that are available and the most efficient way to execute the tasks. When two or more concurrently executing tasks access a shared memory location and if at least one of the accesses is for writing, data race is observed in the program. Data races can introduce non-determinism in the program output making it important to have data …


Variations In Geochemistry And Mineralogy Of Aeolian Dust Deposition To Mountains In Utah And Nevada, Usa, Dylan Binder Dastrup Oct 2016

Variations In Geochemistry And Mineralogy Of Aeolian Dust Deposition To Mountains In Utah And Nevada, Usa, Dylan Binder Dastrup

Theses and Dissertations

Major and trace metal loading to mountains in the western US depends on dust sources, intensity of storms and their availability for transport during snowmelt and runoff. Previous work has been conducted on dust production, composition, and its affect on solar radiation and timing of snow melt. This study was conducted to 1) examine temporal and spatial variability in dust chemistry; 2) evaluate form and availability of major and trace elements in dust; and 3) identify potential dust sources affecting mountains in Utah and Nevada. Spring and summertime dust was collected across northern Utah over the course of three years …


Developing Scripture Literacy: What Good Scripture Readers Know And Do, Eric D. Rackley Sep 2016

Developing Scripture Literacy: What Good Scripture Readers Know And Do, Eric D. Rackley

Religious Educator: Perspectives on the Restored Gospel

This article identifies ten practices that can improve youths’ abilities to make sense of scripture in ways that get them underneath the words to the principles and doctrine that they so desperately need but may struggle to understand. These ten scripture reading practices are based on decades of reading research and empirical work that examine Latter-day Saint youths’ literacy practices and the motivations that drive them. I also include examples, where appropriate, from a two-year ethnographic study of Latter-day Saint youths’ experiences with scripture literacy.


Full Issue Sep 2016

Full Issue

Religious Educator: Perspectives on the Restored Gospel

No abstract provided.


Energy Quantity Estimation In Radiated Acoustic Fields, Eric B. Whiting Sep 2016

Energy Quantity Estimation In Radiated Acoustic Fields, Eric B. Whiting

Theses and Dissertations

Energy quantities, which are calculated from pressure and particle velocity, yield a great deal of information about acoustic fields. Errors in pressure or particle velocity estimation lead to bias errors the estimation of energy quantities. The bias errors arise from different probe configurations and processing methods. Two processing methods are examined: the traditional method and the recently developed Phase and Amplitude Gradient Estimation (PAGE) method. These two methods are compared to investigate how each estimates pressure and particle velocity and the subsequent bias errors in a plane wave, standing wave, and spherical spreading wave field. Analytical expressions are derived for …


Full Issue, Comparative Civilizations Review Sep 2016

Full Issue, Comparative Civilizations Review

Comparative Civilizations Review

No abstract provided.


Creating And Automatically Grading Annotated Questions, Alicia Crowder Wood Sep 2016

Creating And Automatically Grading Annotated Questions, Alicia Crowder Wood

Theses and Dissertations

We have created a question type that allows teachers to easily create questions, helps provide an intuitive user experience for students to take questions, and reduces the time it currently takes teachers to grade and provide feedback to students. This question type, or an "annotated" question, will allow teachers to test students' knowledge in a particular subject area by having students "annotate" or mark text and video sources to answer questions. Through user testing we determined that overall the interface and the implemented system decrease the time it would take a teacher to grade annotated quiz questions. However, there are …


Increasing The Computational Efficiency Of Combinatoric Searches, Wiley Spencer Morgan Sep 2016

Increasing The Computational Efficiency Of Combinatoric Searches, Wiley Spencer Morgan

Theses and Dissertations

A new algorithm for the enumeration of derivative superstructures of a crystal is presented. The algorithm will help increase the efficiency of computational material design methods such as cluster expansion by increasing the size and diversity of the types of systems that can be modeled. Modeling potential alloys requires the exploration of all possible configurations of atoms. Additionally, modeling the thermal properties of materials requires knowledge of the possible ways of displacing the atoms. One solution to finding all symmetrically unique configurations and displacements is to generate the complete list of possible configurations and remove those that are symmetrically equivalent. …


Natural And Anthropogenic Sources Of Arsenic And Nitrate In A Semi-Arid Alluvial Basin; Goshen Valley, Utah, Brian John Selck Sep 2016

Natural And Anthropogenic Sources Of Arsenic And Nitrate In A Semi-Arid Alluvial Basin; Goshen Valley, Utah, Brian John Selck

Theses and Dissertations

Arsenic (As) and nitrate (NO3) are common contaminants in groundwater that are introduced through a variety of natural and anthropogenic sources. In this study we investigated the sources and distribution of As and NO3 in Goshen Valley, Utah, USA. Goshen Valley is a semi-arid alluvial basin that is impacted by geothermal waters, agriculture, urban development, and legacy mining. In this study we sampled surface water, springs, and wells to analyze concentrations of major ions, trace elements (As, B, Ba, Ca, Fe, K, Li, Mg, Mn, Mo, Pb, Si, Sr, Zn), and stable isotopes in water (δ18 …


Rapidscat Slice Spatial Response Function Contour Parameterization, John Clyde Niedfeldt Sep 2016

Rapidscat Slice Spatial Response Function Contour Parameterization, John Clyde Niedfeldt

Theses and Dissertations

The spatial response function (SRF) of the backscatter measurements for a radar scatterometer is often used in reconstruction. It has been found that in many cases the SRF can be approximated as a binary function that is 1 inside the - 6 dB contour of the SRF and 0 outside. This improves the computation speed of reconstruction. Computing the SRF contour can still be a lengthy computation, which can be simplified by precomputing and tabulating key SRF contours. The tabular parameterization for many spinning scatterometers, i.e., QuikSCAT, is straight-forward. For RapidSCAT, this estimation is more involved than other radars due …


Magnus Maximus, A Marvelous Measurer By Kathleen T. Pelley Illustrated By S. D. Schindler, Dana Christine Staples Aug 2016

Magnus Maximus, A Marvelous Measurer By Kathleen T. Pelley Illustrated By S. D. Schindler, Dana Christine Staples

Children's Book and Media Review

No abstract provided.


Full Issue, Children's Book Review Aug 2016

Full Issue, Children's Book Review

Children's Book and Media Review

No abstract provided.


Blockhead: The Life Of Fibonacci, Tessa Mcmillan Aug 2016

Blockhead: The Life Of Fibonacci, Tessa Mcmillan

Children's Book and Media Review

No abstract provided.


Modeling, Fabrication, And Testing Of A Multicellular Nanoinjection Lance Array, Zachary Lindstrom, Steven Brewer, Melanie Easter, Brian Jensen Aug 2016

Modeling, Fabrication, And Testing Of A Multicellular Nanoinjection Lance Array, Zachary Lindstrom, Steven Brewer, Melanie Easter, Brian Jensen

Biomedical Engineering Western Regional Conference

No abstract provided.


Why Are Wrist Rotations Considerably Less Smooth Than Reaching Movements?, Layne Hancock Salmond, Steven Knight Charles Aug 2016

Why Are Wrist Rotations Considerably Less Smooth Than Reaching Movements?, Layne Hancock Salmond, Steven Knight Charles

Biomedical Engineering Western Regional Conference

No abstract provided.


Plasmid Dna Bind And Elute Chromatography Using Borosilicate Filters And Filter Holders, Stacey D. Floyd, Camille S. Baird, Jordan Finnell, Tsz Ming Tsang, Robert C. Davis, Kenneth A. Christensen Aug 2016

Plasmid Dna Bind And Elute Chromatography Using Borosilicate Filters And Filter Holders, Stacey D. Floyd, Camille S. Baird, Jordan Finnell, Tsz Ming Tsang, Robert C. Davis, Kenneth A. Christensen

Student Works

This research has been completed to determine whether plasmid DNA will bind to a simple borosilicate filter in a reusable filter holder, and whether it can be released in a controlled procedure after a wash has been done to eliminate impurities.

The motivation for this is to help small research groups, both in educational settings as well as in other small research settings be able to study isolated DNA without much of the expense generally associated with purification kits and to remove the limitations on trial numbers imposed by the expense of each individual isolation kit.

Medical research, forensics, and …


Daxton Hawks Reu Prospectus, Daxton A. Hawks Aug 2016

Daxton Hawks Reu Prospectus, Daxton A. Hawks

Student Works

The purpose of my research is to investigate the ability of the PAGE method to improve the frequency bandwidth of calculations of energy-based quantities from multiple pressure microphones. I will accomplish this by investigating sound waves in both plane-wave and standing-wave environments. I will compare the PAGE method calculations for Ia, Ir, Ep, Ek, and Z to those of traditional and analytical expressions, based on careful ambient condition monitoring. Quantifying the bandwidth extension of the PAGE method for these energy-based quantities will lay a foundation for further application.