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2019

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Engineering Education Professional Development For Teachers In The Delta Greely School District, Jennifer Dougherty Dec 2019

Engineering Education Professional Development For Teachers In The Delta Greely School District, Jennifer Dougherty

Education

Over the last two decades engineering has become a new focus in many science curricula, in part due to the emphasis on STEM (science, technology, engineering, and math) education. Most teachers lack training or education in engineering and are not adequately prepared to implement effective engineering education. This research identifies the needs and constraints of one district, the Delta Greely School District (DGSD), in Delta Junction, AK (approximately 750 students district-wide). Surveys were distributed to fifty teachers and five administrators to gather information on attitudes and beliefs surrounding engineering education. Focus groups were conducted with teachers and administrators to better …


Subglacial Meltwater Supported Aerobic Marine Habitats During Snowball Earth, Maxwell A. Lechte, Malcolm W. Wallace, Ashleig Van Smeerdijk Hooda, Weiqiang Li, Ganqing Jiang, Galen P. Halverson, Dan Asael, Stephanie L. Mccoll, Noah J. Planavsky Dec 2019

Subglacial Meltwater Supported Aerobic Marine Habitats During Snowball Earth, Maxwell A. Lechte, Malcolm W. Wallace, Ashleig Van Smeerdijk Hooda, Weiqiang Li, Ganqing Jiang, Galen P. Halverson, Dan Asael, Stephanie L. Mccoll, Noah J. Planavsky

Geoscience Faculty Research

The Earth’s most severe ice ages interrupted a crucial interval in eukaryotic evolution with widespread ice coverage during the Cryogenian Period (720 to 635 Ma). Aerobic eukaryotes must have survived the “Snowball Earth” glaciations, requiring the persistence of oxygenated marine habitats, yet evidence for these environments is lacking. We examine iron formations within globally distributed Cryogenian glacial successions to reconstruct the redox state of the synglacial oceans. Iron isotope ratios and cerium anomalies from a range of glaciomarine environments reveal pervasive anoxia in the ice-covered oceans but increasing oxidation with proximity to the ice shelf grounding line. We propose that …


In‐Situ Extraction And Impregnation Of Black Walnut Husk Into Polyethylene Film Using Supercritical Carbon Dioxide With An Ethanol Modifier, Jonathan Wenzel, Veronica R. Moorman, Lihua Wang, Isaiah Spencer-Williams, Mitchell Hall, Cheryl Samaniego, Michelle Ammerman Dec 2019

In‐Situ Extraction And Impregnation Of Black Walnut Husk Into Polyethylene Film Using Supercritical Carbon Dioxide With An Ethanol Modifier, Jonathan Wenzel, Veronica R. Moorman, Lihua Wang, Isaiah Spencer-Williams, Mitchell Hall, Cheryl Samaniego, Michelle Ammerman

Chemistry & Biochemistry Publications

Walnuts are commonly cultivated for their kernel, which is a rich source of antioxidant phenolic compounds. The husk likewise contains antioxidant and antimicrobial compounds, but is typically discarded without further processing. Antioxidant compounds are useful in creating active packaging films, but typically decompose at melt extrusion temperatures in polymer processing. Due to carbon dioxide's low critical point and ability to swell polymer films, supercritical carbon dioxide may be used to impregnate phenolic compounds into polymers. For this study, a novel technique is used to simultaneously produce walnut husk extracts and impregnate the extract into polymer films in the same batch …


Analytic Non-Adiabatic Derivative Coupling Terms For Spin-Orbit Mrci Wavefunctions. I. Formalism, Lachlan T. Belcher, Gary S. Kedziora, David E. Weeks Dec 2019

Analytic Non-Adiabatic Derivative Coupling Terms For Spin-Orbit Mrci Wavefunctions. I. Formalism, Lachlan T. Belcher, Gary S. Kedziora, David E. Weeks

Faculty Publications

Analytic gradients of electronic eigenvalues require one calculation per nuclear geometry, compared to at least 3n + 1 calculations for finite difference methods, where n is the number of nuclei. Analytic nonadiabatic derivative coupling terms (DCTs), which are calculated in a similar fashion, are used to remove nondiagonal contributions to the kinetic energy operator, leading to more accurate nuclear dynamics calculations than those that employ the Born-Oppenheimer approximation, i.e., that assume off-diagonal contributions are zero. The current methods and underpinnings for calculating both of these quantities, gradients and DCTs, for the State-Averaged MultiReference Configuration Interaction with Singles and Doubles (MRCI-SD) …


Best Practices And Metrics For Virtual Reality User Interfaces, Jay Byam Dec 2019

Best Practices And Metrics For Virtual Reality User Interfaces, Jay Byam

Computer Science

Virtual Reality (VR) technology has become increasingly effective and accessible within the past decade [15]. With this increase in the technology’s prevalence and cultural significance, certain interaction techniques and design choices have emerged as the most widely used and recommended. This research effort employs a VR experiment in which multiple selection methods, interface placements, and navigation techniques are compared side-by-side, and performance metrics and preference data are collected. Both best practice and to-be-avoided methods are examined, and the performance and preference data is analyzed. Determinations made based on the data gathered are partly in-line with expectations according to best practices, …


Electrochemical Hydrogen Evolution Over Hydrothermally Synthesized Re-Doped Mos2 Flower-Like Microspheres, Juan Aliaga, Pablo Vera, Juan Araya, Luis Ballesteros, Julio Urzúa, Mario Farías, Francisco Paraguay-Delgado, Gabriel Alonso-Núñez, Guillermo González, Eglantina Benavente Dec 2019

Electrochemical Hydrogen Evolution Over Hydrothermally Synthesized Re-Doped Mos2 Flower-Like Microspheres, Juan Aliaga, Pablo Vera, Juan Araya, Luis Ballesteros, Julio Urzúa, Mario Farías, Francisco Paraguay-Delgado, Gabriel Alonso-Núñez, Guillermo González, Eglantina Benavente

Faculty, Staff and Students Publications

In this research, we report a simple hydrothermal synthesis to prepare rhenium (Re)- doped MoS2 flower-like microspheres and the tuning of their structural, electronic, and electrocatalytic properties by modulating the insertion of Re. The obtained compounds were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), high-resolution transmission electron microscopy (HRTEM), Raman spectroscopy, and X-ray photoelectron spectroscopy (XPS). Structural, morphological, and chemical analyses confirmed the synthesis of poorly crystalline Re-doped MoS2 flower-like microspheres composed of few stacked layers. They exhibit enhanced hydrogen evolution reaction (HER) performance with low overpotential of 210 mV at current density of 10 mA/cm2, with a …


Veteran Religion Journalist Named Senior Fellow At Overby Center, Staff Report Dec 2019

Veteran Religion Journalist Named Senior Fellow At Overby Center, Staff Report

University of Mississippi News

Terry Mattingly has earned national reputation for observing how religion affects daily life


Using Nano- And Micro- Structural Materials For Concrete Environmental Applications, Hala Nabeel Elia Dec 2019

Using Nano- And Micro- Structural Materials For Concrete Environmental Applications, Hala Nabeel Elia

Theses and Dissertations

Utilized globally in the construction industry, concrete is an integral component of homes, roads, airports, skyscrapers, and tunnels. Traditional concrete components are cement, fine aggregate (sand), coarse aggregate (gravel or crushed stone), and water. When cement and water compound together they will make a paste which binds all the aggregates together to make the concrete. Unfortunately, every one ton of cement manufactured emits 0.9 ton of CO2into the air. The goal of this two-part work was to obtain an environmentally friendly concrete. The first part used supplementary cementitious materials (SCM), fly ash and silica fume, to create concrete with high …


Research On Color Matching Model For Color Qr Code, Fei You Dr., Qingli Zhang Dr., Bruce Welt Prof. Dec 2019

Research On Color Matching Model For Color Qr Code, Fei You Dr., Qingli Zhang Dr., Bruce Welt Prof.

Journal of Applied Packaging Research

Objective To provide a faster and more effective way for consumers to obtain the additional information of product, the color quick response (QR) code is printed on product packaging. To improve decoding accuracy of color QR codes. This paper constructs a color matching model with good performance, which restrains aliasing between two color encoding modules of color QR code. Methods By comparing and analyzing the character of several typical color spaces, the HSV color space was chosen for its favorable attributes. Based on the enlarging capacity principle of color QR code and the maximum rule of relative Euclidean distance, 2 …


Multiple Agent Target Tracking In Gps-Denied Environments, Skyler Tolman Dec 2019

Multiple Agent Target Tracking In Gps-Denied Environments, Skyler Tolman

Theses and Dissertations

Unmanned aerial systems (UAS) are effective for surveillance and monitoring, but struggle with persistent, long-term tracking, especially without GPS, due to limited flight time. Persistent tracking can be accomplished using multiple vehicles if one vehicle can effectively hand off the tracking information to another replacement vehicle. This work presents a solution to the moving-target handoff problem in the absence of GPS. The proposed solution (a) a nonlinear complementary filter for self-pose estimation using only an IMU, (b) a particle filter for relative pose estimation between UAS using a relative range (c) visual target tracking using a gimballed camera when the …


Um Professors Collaborate With Counterparts Through Sec Grant, Shea Stewart Dec 2019

Um Professors Collaborate With Counterparts Through Sec Grant, Shea Stewart

University of Mississippi News

Faculty Travel Program encourages, supports conference partnerships


Replication Study: Biomechanical Remodeling Of The Microenvironment By Stromal Caveolin-1 Favors Tumor Invasion And Metastasis, Mee Rie Sheen, Jennifer L. Fields, Brian Northan, Judith Lacoste, Lay-Hong Ang, Steven Fiering Dec 2019

Replication Study: Biomechanical Remodeling Of The Microenvironment By Stromal Caveolin-1 Favors Tumor Invasion And Metastasis, Mee Rie Sheen, Jennifer L. Fields, Brian Northan, Judith Lacoste, Lay-Hong Ang, Steven Fiering

Dartmouth Scholarship

As part of the Reproducibility Project: Cancer Biology we published a Registered Report (Fiering et al., 2015) that described how we intended to replicate selected experiments from the paper ‘Biomechanical remodeling of the microenvironment by stromal caveolin-1 favors tumor invasion and metastasis’ (Goetz et al., 2011). Here we report the results. Primary mouse embryonic fibroblasts (pMEFs) expressing caveolin 1 (Cav1WT) demonstrated increased extracellular matrix remodeling in vitro compared to Cav1 deficient (Cav1KO) pMEFs, similar to the original study (Goetz et al., 2011). In vivo, we found higher levels of intratumoral stroma remodeling, determined by fibronectin fiber orientation, in tumors …


Polyvinyl Alcohol Hydrogels, Payal Hukeri Dec 2019

Polyvinyl Alcohol Hydrogels, Payal Hukeri

Mechanical Engineering and Materials Science Independent Study

White matter in the brain is anisotropic, which means it has directionally dependent properties, and has a stiffness of 1-3 KPa. The objective of this project was to create PVA that mimicked these properties well. A hydrogel that mimicked the properties of the brain was to be created and the process had to be easily replicable. Polyvinyl Alcohol is a water soluble synthetic polymer and can be made into a hydrogel. From the DST and Biaxial testing that was completed this semester, as well as the Uniaxial and Rheometry testing completed in previous semesters, the mechanical properties of PVA have …


Ecological Interactions Among Important Groundfishes In The Gulf Of Alaska, Cheryl L. Barnes Dec 2019

Ecological Interactions Among Important Groundfishes In The Gulf Of Alaska, Cheryl L. Barnes

Fisheries

Complex ecological interactions such as predation and competition play an important role in shaping the structure and function of marine communities. In fact, these processes can have greater impacts than those related to fishing. We assessed ecological interactions among economically important fishes in the Gulf of Alaska - a large marine ecosystem that has recently undergone considerable shifts in community composition. Specifically, we developed an index of predation for Walleye Pollock (Gadus chalcogrammus) to examine spatiotemporal changes in consumption, quantify portfolio effects, and better understand diversity-stability relationships within the demersal food web. We also evaluated the potential for competition between …


Bubble Pinch-Off In Turbulence, Daniel J. Ruth, Wouter Mostert, Stephane Perrard, Luc Deike Dec 2019

Bubble Pinch-Off In Turbulence, Daniel J. Ruth, Wouter Mostert, Stephane Perrard, Luc Deike

Mechanical and Aerospace Engineering Faculty Research & Creative Works

Although bubble pinch-off is an archetype of a dynamical system evolving toward a singularity, it has always been described in idealized theoretical and experimental conditions. Here, we consider bubble pinch-off in a turbulent flow representative of natural conditions in the presence of strong and random perturbations, combining laboratory experiments, numerical simulations, and theoretical modeling. We show that the turbulence sets the initial conditions for pinch-off, namely the initial bubble shape and flow field, but after the pinch-off starts, the turbulent time at the neck scale becomes much slower than the pinching dynamics: The turbulence freezes. We show that the average …


Flying The Frontier: A Case Study Comparison Of Newspaper Coverage Of Early Northern Plane Crashes, Leanna Prax Williams Dec 2019

Flying The Frontier: A Case Study Comparison Of Newspaper Coverage Of Early Northern Plane Crashes, Leanna Prax Williams

Arctic and Northern Studies

From the early days of Alaskan aviation beginning in 1923, stories about Alaskan bush pilots leapt from newspaper pages, captivating readers and selling papers. These newspaper stories, along with magazine articles and other popular culture media accounts, portrayed pilots as pioneers, cowboys and brave adventurers, and referred to Alaska in terms heavily laden with American frontier imagery, a trend that persisted in Alaska but faded elsewhere. What did newspaper reports convey about the lives and deaths of these aviators and their relationships to Alaska and the frontier? How has the portrayal of these early Alaskan pilots in ways that perpetuated …


Ballot Readability And Plain Language, Roger Poole Dec 2019

Ballot Readability And Plain Language, Roger Poole

Master of Arts in Professional Writing Capstones

The goal of this study was to examine the effect that readability and plain language had on voters' responses to Georgia's five legislatively-referred constitutional amendments (LRCA) in the November 2018 election. This study sought to answer the following questions regarding ballot readability and plain language:

  1. Do voters distinguish the difference between traditionally composed ballots and plain language ballots?
  2. Do voters have a preference between conventional worded ballots and reworded ballot language that improved readability?

Given that partisan lawyers and lobbyists write many state ballot questions, there may be tendencies to compose legislatively-referred constitutional amendments in confusing and unclear language designed …


Lung Pattern Classification Via Dcnn, Zhuoqi Sun Dec 2019

Lung Pattern Classification Via Dcnn, Zhuoqi Sun

Master of Science in Computer Science Theses

Interstitial lung disease (ILD) causes pulmonary fibrosis. The correct classification of ILD plays a crucial role in the diagnosis and treatment process. In this research work, we disclose a lung nodules recognition method based on a deep convolutional neural network (DCNN) and global features, which can be used for computer-aided diagnosis (CAD) of global features of lung nodules. Firstly, a DCNN is constructed based on the characteristics and complexity of lung computerized tomography (CT) images. Then discussed the effects of different iterations on the recognition results and influence of different model structures on the global features of lung nodules. We …


The Role Of Tundra Vegetation In The Arctic Water Cycle, Jason A. Clark Dec 2019

The Role Of Tundra Vegetation In The Arctic Water Cycle, Jason A. Clark

Engineering

Vegetation plays many roles in Arctic ecosystems, and the role of vegetation in linking the terrestrial system to the atmosphere through evapotranspiration is likely important. Through the acquisition and use of water, vegetation cycles water back to the atmosphere and modifies the local environment. Evapotranspiration is the collective term used to describe the transfer of water from vascular plants (transpiration) and non-vascular plants and surfaces (evaporation) to the atmosphere. Evapotranspiration is known to return large portions of the annual precipitation back to the atmosphere, and it is thus a major component of the terrestrial Arctic hydrologic budget. However, the relative …


Classification And Signal Processing Of Radio Backscatter From Meteors, Jared Klemm Dec 2019

Classification And Signal Processing Of Radio Backscatter From Meteors, Jared Klemm

Engineering

Ground-based radar systems are routinely used to detect the trails of ionized particles that are formed by meteoroids falling through Earth's atmosphere. The most common use for these meteor radar systems is for atmospheric wind studies of the mesosphere and lower thermosphere (80-100 km altitude). Because these meteor trails are embedded in the background winds of the middle atmosphere, atmospheric winds in that region can be measured by observing the radial velocities of the trails. There has also been a considerable amount of research over the last few decades into estimation of neutral atmospheric temperatures using the measured decay time …


Laboratory Investigation Of Infiltration Process Of Nonnewtonian Fluids Through Porous Media In A Non-Isothermal Flow Regime For Effective Remediation Of Adsorbed Contaminants, Fawad Naseer Dec 2019

Laboratory Investigation Of Infiltration Process Of Nonnewtonian Fluids Through Porous Media In A Non-Isothermal Flow Regime For Effective Remediation Of Adsorbed Contaminants, Fawad Naseer

Engineering

Contamination of soil and groundwater have serious health implications for man and environment. The overall goal of this research is to study a methodology of using nonNewtonian fluids for effective remediation of adsorbed contaminants in porous media under nonisothermal flow regimes. Non-Newtonian fluids (Guar gum and Xanthan gum solutions) provide a high viscous solution at low concentration and these fluids adjust their viscosities with applied shear rate and change in temperature. Adjustment of viscosity with an applied rate of shear is vital for contaminant remediation because non-Newtonian shear thinning fluids can penetrate to low permeability zones in subsurface by decreasing …


Retrodirective Phased Array Antenna For Nanosatellites, Justin W. Long Dec 2019

Retrodirective Phased Array Antenna For Nanosatellites, Justin W. Long

Engineering

This thesis presents a S-band phased array antenna for CubeSat applications. Existing state-of the-art high gain antenna systems are not well suited to the majority of CubeSats, those that fall within the 1U (10 cm x 10 cm x 10 cm) to 3U (10 cm x 10 cm x 30 cm) size ranges and in Low Earth Orbit (LEO). The system presented in this thesis is designed specifically to meet the needs of those satellites. This system is designed to fit on the 1U face (10 cm x 10 cm) of a CubeSat and requires no deployables. The use of …


Prudhoe Bay West End Gas Lift Supply Optimization, Irwin Chou Dec 2019

Prudhoe Bay West End Gas Lift Supply Optimization, Irwin Chou

Engineering

The western extension of Alaska's Prudhoe Bay, known collectively as Eileen West End (EWE), operates under a gas lift pressure supply constraint. This constraint is largely contributed by two factors: the extensively long gas lift supply line that stretches across the western field and the large number of production wells offtaking gas lift to stay online or enhance production. The gas lift supply line is approximately 18.5 miles long and provides gas lift to 200+ production wells. This results in a pressure drop severe enough to start hindering production on the western most side of the field as low gas …


Renewable Energy Development In Alaska: Policy Implications For The Development Of Renewable Energy For Remote Areas Of The Circumpolar Arctic, Gwen Pamela Holdmann Dec 2019

Renewable Energy Development In Alaska: Policy Implications For The Development Of Renewable Energy For Remote Areas Of The Circumpolar Arctic, Gwen Pamela Holdmann

Engineering

The territories that comprise the Arctic region are part of some of wealthiest and most advanced countries on the planet; yet, rural Alaska, northern Canada, the Russian Far East and Greenland--characterized by off-grid communities, regional grids, and higher degrees of energy insecurity--have more in common with the developing world than the southern regions of their own country. This thesis explains this paradox of energy development in the Circumpolar North and tackles the issue of developing renewable energy in remote areas where technical and socioeconomic barriers are significant. The primary research questions are two-fold: 1) Why did the Alaska electrical system …


Exploiting Memristors For Compressive Sensing Applications, Fengyu Qian Dec 2019

Exploiting Memristors For Compressive Sensing Applications, Fengyu Qian

Doctoral Dissertations

The amount of sensory signal is increasing dramatically as we’re stepping into the era of Internet of Things (IoT). Compressive Sensing (CS), feature as Sub-Nyquist sampling rate and low complexity sensing architectures, is very promising for these kinds of applications where resources are restricted. Through applying this novel compression technology, data size of sensory signals are largely compressed such that it is very efficient within the signal processing, data transmitting and storage processes. Compared to conventional codec method, CS technique requires less hardware resources and achieve lower power consumption within sensor nodes.

However, there are several bottle-necks of existing compressive …


Analysis Of The Duration And Energy Consumption Of Aes Algorithms On A Contiki-Based Iot Device, Brandon Tsao Dec 2019

Analysis Of The Duration And Energy Consumption Of Aes Algorithms On A Contiki-Based Iot Device, Brandon Tsao

Computer Science and Engineering Master's Theses

With the growing prevalence of the Internet of Things, securing the sheer abundance of devices is critical. The current IoT and security landscapes lack empirical metrics on encryption algorithm implementations that are optimized for constrained devices, such as encryption/decryption duration and energy consumption. In this paper, we achieve two things. First, we survey for optimized implementations of symmetric encryption algorithms. Seconds, we study the performance of various symmetric encryption algorithms on a Contiki-based IoT device. This paper provides encryption and decryption durations and energy consumption results on three implementations of AES: TinyAES, B-Con’s AES, and Contiki’s own built-in AES. In …


An Architecture Of Connections: The Ballybrack Cooperative 1969-1972, Brian Ward Dec 2019

An Architecture Of Connections: The Ballybrack Cooperative 1969-1972, Brian Ward

Research Outputs: 2025-Present

No abstract provided.


Castlepark: A Vernacular Architecture For Modern Ireland 1969-1972, Brian Ward Dec 2019

Castlepark: A Vernacular Architecture For Modern Ireland 1969-1972, Brian Ward

Research Outputs: 2025-Present

No abstract provided.


Effects Of Target Properties On The Formation Of Lunar Impact Craters In The Simple-To-Complex Transition, Mitali Chandnani Dec 2019

Effects Of Target Properties On The Formation Of Lunar Impact Craters In The Simple-To-Complex Transition, Mitali Chandnani

Geosciences

The transition from simple to complex crater morphology in impact craters with increase in crater size has been modelled and observed in planetary bodies across the Solar System. The transition diameter depends upon the strength and gravity of the planetary body. On the Moon, this transition takes place over a diameter range of several kilometers. This range spans a diversity of crater morphologies including simple, transitional and complex craters. The diameter range of 15 20 km falls within the lunar simple-to-complex transition. All other impactor properties held constant, the 15-20 km range corresponds to a factor of three in the …


Radiome: Artificially Intelligent Radio For People With Dementia, S Venkatesh, D Moffat, Er Miranda Dec 2019

Radiome: Artificially Intelligent Radio For People With Dementia, S Venkatesh, D Moffat, Er Miranda

School of Art, Design and Architecture

No abstract provided.