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2017

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Analytical Solution For Determination The Control Parameter In The Inverse Parabolic Equation Using Ham, M. M. Khader Dec 2017

Analytical Solution For Determination The Control Parameter In The Inverse Parabolic Equation Using Ham, M. M. Khader

Applications and Applied Mathematics: An International Journal (AAM)

In this article, the homotopy analysis method (HAM) for obtaining the analytical solution of the inverse parabolic problem and computing the unknown time-dependent parameter is introduced. The series solution is developed and the recurrence relations are given explicitly. Special attention is given to satisfy the convergence of the proposed method. A comparison of HAM with the variational iteration method is made. In the HAM, we use the auxiliary parameter ~ to control with a simple way in the convergence region of the solution series. Applying this method with several


Too Many Choices Confuse Patients With Dementia, R. C. Hamdy, J. V. Lewis, Amber Kinser, A. Depelteau, Rebecca Copeland, T. Kendall-Wilson, K. Whalen Dec 2017

Too Many Choices Confuse Patients With Dementia, R. C. Hamdy, J. V. Lewis, Amber Kinser, A. Depelteau, Rebecca Copeland, T. Kendall-Wilson, K. Whalen

ETSU Faculty Works

Choices are often difficult to make by patients with Alzheimer Dementia. They often become acutely confused when faced with too many options because they are not able to retain in their working memory enough information about the various individual choices available. In this case study, we describe how an essentially simple benign task (choosing a dress to wear) can rapidly escalate and result in a catastrophic outcome. We examine what went wrong in the patient/caregiver interaction and how that potentially catastrophic situation could have been avoided or defused.


Determining Detection Limits Of Aqueous Anions Using Electrochemical Impedance Spectroscopy, Dane W. Scott, Yahya Alseiha Dec 2017

Determining Detection Limits Of Aqueous Anions Using Electrochemical Impedance Spectroscopy, Dane W. Scott, Yahya Alseiha

ETSU Faculty Works

Background: Pulsed amperometric detection is a relatively new method for detection of ions and especially non-electrolytes such as carbohydrates in aqueous solutions. Pulsed amperometric detection relies on a redox reaction while electrochemical impedance simply measures the real and capacitive resistant of the solution. There is a correlation between the real impedance of a solution and the ionic strength of the solution. Method: This work explores measuring real impedance of pure water as a function of temperature from 25.0 to 60.0 °C to determine the relationship between impedance and temperature. Maintaining temperature at 25.0 °C, solutions of sodium chloride, potassium carbonate, …


Ion Trajectory Simulations And Design Optimization Of Toroidal Ion Trap Mass Spectrometers, Jessica Marie Higgs Dec 2017

Ion Trajectory Simulations And Design Optimization Of Toroidal Ion Trap Mass Spectrometers, Jessica Marie Higgs

Theses and Dissertations

Ion traps can easily be miniaturized to become portable mass spectrometers. Trapped ions can be ejected by adjusting voltage settings of the radiofrequency (RF) signal applied to the electrodes. Several ion trap designs include the quadrupole ion trap (QIT), cylindrical ion trap (CIT), linear ion trap (LIT), rectilinear ion trap (RIT), toroidal ion trap, and cylindrical toroidal ion trap. Although toroidal ion traps are being used more widely in miniaturized mass spectrometers, there is a lack of fundamental understanding of how the toroidal electric field affects ion motion, and therefore, the ion trap's performance as a mass analyzer. Simulation programs …


Evaluating The Affective Impact Of A Place-Based Learning Course Project In The Geosciences, Nathan Charlton Dec 2017

Evaluating The Affective Impact Of A Place-Based Learning Course Project In The Geosciences, Nathan Charlton

Masters Theses

Coping with issues such as climate change and depletion of natural resources demands a scientifically literate public. For many students, the only exposure to earth science comes in a college-level general education geoscience course. One way to engender positive attitudes toward and interest in earth science among these students (the future public) is to connect learning to actual places to which students have a personal attachment.

This study seeks to evaluate the impact of a place-based learning project (MyPlace) currently in use in an introductory geosciences general education course at Western Michigan University. Students in the MyPlace project select a …


On The Ground State And Evolution Of Structural And Transport Properties Of Tin Selenide, Yufei Liu Dec 2017

On The Ground State And Evolution Of Structural And Transport Properties Of Tin Selenide, Yufei Liu

All Dissertations

The recent surge of interest in tin selenide (SnSe) is due to the reported record-high thermoelectric figure of merit at elevated temperatures. While the researchers are exerting tremendous efforts to further improve the thermoelectric performance of SnSe via doping and nanostructuring, it is getting more and more apparent that SnSe is fascinating in many aspects of fundamental physics. SnSe is, in many aspects, an outlier of the current materials selection rules for high thermoelectric performance. Hence, answering why thermoelectric performance is high in SnSe should come before addressing how to further improve its thermoelectric performance. To this end, there are …


Graph Analytics Methods In Feature Engineering, Theophilus Siameh Dec 2017

Graph Analytics Methods In Feature Engineering, Theophilus Siameh

Electronic Theses and Dissertations

High-dimensional data sets can be difficult to visualize and analyze, while data in low-dimensional space tend to be more accessible. In order to aid visualization of the underlying structure of a dataset, the dimension of the dataset is reduced. The simplest approach to accomplish this task of dimensionality reduction is by a random projection of the data. Even though this approach allows some degree of visualization of the underlying structure, it is possible to lose more interesting underlying structure within the data. In order to address this concern, various supervised and unsupervised linear dimensionality reduction algorithms have been designed, such …


Weed Establishment And Persistence After Water Pipeline Installation And Reclamation In The Mixed Grass Prairie Of Western North Dakota, Erin K. Espeland, Lora B. Perkins Dec 2017

Weed Establishment And Persistence After Water Pipeline Installation And Reclamation In The Mixed Grass Prairie Of Western North Dakota, Erin K. Espeland, Lora B. Perkins

Natural Resource Management Faculty Publications

Weeds in reclamations interfere with success by: 1) competing with desirable species seeded during revegetation; 2) preventing recolonization of reclamations by native species; and 3) reducing the integrity of landscapes by expanding from reclamations into adjacent, intact areas. In the Bakken oilfield of western North Dakota, dispersed reclamation activity and increased traffic may provide many opportunities for weeds to spread. To determine the potential for disturbance and reclamation to increase resident weed populations and introduce new weed species, we tracked twenty-one weed (non-native/ruderal/invasive) species over a four-year period after the installation of a 1.8 km livestock water pipeline and subsequent …


Quantitative Morphological Classification Of Planetary Craterforms Using Multivariate Methods Of Outline-Based Shape Analysis, Thomas Joseph Slezak Dec 2017

Quantitative Morphological Classification Of Planetary Craterforms Using Multivariate Methods Of Outline-Based Shape Analysis, Thomas Joseph Slezak

Theses and Dissertations

Craters formed by impact and volcanic processes are among the most fundamental planetary landforms. This study examines the morphology of diverse craterforms on Io, the Moon, Mars, and Earth using quantitative, outline-based shape analysis and multivariate statistical methods to evaluate the differences between different types of. Ultimately, this should help establish relationships between the form and origin of craterforms. Developed in the field of geometric morphometrics by paleontological and biological sciences communities, these methods were used for the analysis of the shapes of crater outlines. The shapes of terrestrial ash-flow calderas, terrestrial basaltic shield calderas, martian calderas, Ionian paterae, and …


A Coverage Metric To Aid In Testing Multi-Agent Systems, Jane Ostergar Linn Dec 2017

A Coverage Metric To Aid In Testing Multi-Agent Systems, Jane Ostergar Linn

Theses and Dissertations

Models are frequently used to represent complex systems in order to test the systems before they are deployed. Some of the most complicated models are those that represent multi-agent systems (MAS), where there are multiple decision makers. Brahms is an agent-oriented language that models MAS. Three major qualities affect the behavior of these MAS models: workframes that change the state of the system, communication activities that coordinate information between agents, and the schedule of workframes. The primary method to test these models that exists is repeated simulation. Simulation is useful insofar as interesting test cases are used that enable the …


Shadow Patching: Exemplar-Based Shadow Removal, Ryan Sears Hintze Dec 2017

Shadow Patching: Exemplar-Based Shadow Removal, Ryan Sears Hintze

Theses and Dissertations

Shadow removal is an important problem for both artists and algorithms. Previous methods handle some shadows well but, because they rely on the shadowed data, perform poorly in cases with severe degradation. Image-completion algorithms can completely replace severely degraded shadowed regions, and perform well with smaller-scale textures, but often fail to reproduce larger-scale macrostructure that may still be visible in the shadowed region. This paper provides a general framework that leverages degraded (e.g., shadowed) data to guide the image completion process by extending the objective function commonly used in current state-of-the-art image completion energy-minimization methods. This approach achieves realistic shadow …


Recommender Systems For Family History Source Discovery, Derrick James Brinton Dec 2017

Recommender Systems For Family History Source Discovery, Derrick James Brinton

Theses and Dissertations

As interest in family history research increases, greater numbers of amateurs are participating in genealogy. However, finding sources that provide useful information on individuals in genealogical research is often an overwhelming task, even for experts. Many tools assist genealogists in their work, including many computer-based systems. Prior to this work, recommender systems had not yet been applied to genealogy, though their ability to navigate patterns in large amounts of data holds great promise for the genealogical domain. We create the Family History Source Recommender System to mimic human behavior in locating sources of genealogical information. The recommender system is seeded …


Real-Time Beamforming Algorithms For The Focal L-Band Array On The Green Bank Telescope, Mark William Ruzindana Dec 2017

Real-Time Beamforming Algorithms For The Focal L-Band Array On The Green Bank Telescope, Mark William Ruzindana

Theses and Dissertations

A phased array feed (PAF) provides a contiguous, electronically synthesized wide field of view for large-dish astronomical observatories. Significant progress has been made in recent years in improving the sensitivity of PAF receivers though optimizing the design of the antenna array, cryogenic cooling of the front end, and implementation of real-time correlation and beamforming in digital signal processing. FLAG is a 19 dual-polarized element phased array with cryogenic LNAs, direct digitization of RF signals at the front end, digital signal transport over fiber, and a real time signal processing back end with up to 150 MHz bandwidth. The digital back …


Design And Analysis Of Compressed Air Power Harvesting Systems, Zachary James Sadler Dec 2017

Design And Analysis Of Compressed Air Power Harvesting Systems, Zachary James Sadler

Theses and Dissertations

Procedure for site discovery, system design, and optimization of power harvesting systems is developed with an emphasis on application to air compressors. Limitations for the usage of infrared pyrometers is evaluated. A system of governing equations for thermoelectric generators is developed. A solution method for solving the system of equations is created in order to predict power output from the device. Payback analysis is proposed for determining economic viability. A genetic algorithm is used to optimize the power harvesting system payback with changing quantities and varieties of thermoelectric generators, as well as the back work put into cooling the thermoelectric …


Ab Initio Structural Studies Of Cyclobutylmethyl Cations: Effect Of Fluoroalkyl Groups On The Relative Stability Of The Carbocations, Prakash Reddy, Golam Rasul, G. K. Surya Prakash Dec 2017

Ab Initio Structural Studies Of Cyclobutylmethyl Cations: Effect Of Fluoroalkyl Groups On The Relative Stability Of The Carbocations, Prakash Reddy, Golam Rasul, G. K. Surya Prakash

Chemistry Faculty Research & Creative Works

Ab initio calculations at MP2/cc-pVTZ level show that the trifluoromethyl group has a strong destabilizing effect on the nonclassical, σ-bridged cyclobutylmethyl cations. The GIAO-MP2 derived 13C NMR chemical shifts indicate substantial charge delocalization from the neighboring cyclobutyl ring for carbocations with an α-fluorolkyl group as compared to the 1-cyclobutylethyl cation, and this enhanced charge delocalization in case of the α-(trifluoromethyl)cyclobutylmethyl cation would lead to the ring-opening rearrangement to form the relatively more stable nonclassical primary cyclobutylmethyl cation, in which the carbocation center is farthest from the strongly electron-withdrawing trifluoromethyl group.


250 Words Of I Don't Understand: Reading Struggles For Freshmen College Students, Alicia Bushey Dec 2017

250 Words Of I Don't Understand: Reading Struggles For Freshmen College Students, Alicia Bushey

Capstone Projects and Master's Theses

The focus of this Capstone project is on the reading struggles of first year college students. This is important because reading is a fundamental need in secondary education and in our society. If people are challenged in this area, they will struggle both in higher education, as well as certain aspects of daily living. The three primary stakeholder perspectives examined were college teachers and tutors, because of their relevant expertise, as well as their roles and responsibilities. Based on an analysis of the data and the relevant research literature, action was taken to help first-year college students overcome their reading …


A Bayesian Network Meta-Analysis To Synthesize The Influence Of Contexts Of Scaffolding Use On Cognitive Outcomes In Stem Education, Brian Robert Belland, Andrew Walker, Nam Ju Kim Dec 2017

A Bayesian Network Meta-Analysis To Synthesize The Influence Of Contexts Of Scaffolding Use On Cognitive Outcomes In Stem Education, Brian Robert Belland, Andrew Walker, Nam Ju Kim

Instructional Technology and Learning Sciences Faculty Publications

Computer-based scaffolding provides temporary support that enables students to participate in and become more proficient at complex skills like problem solving, argumentation, and evaluation. While meta-analyses have addressed between-subject differences on cognitive outcomes resulting from scaffolding, none has addressed within-subject gains. This leaves much quantitative scaffolding literature not covered by existing meta-analyses. To address this gap, this study used Bayesian network meta-analysis to synthesize within-subjects (pre–post) differences resulting from scaffolding in 56 studies. We generated the posterior distribution using 20,000 Markov Chain Monte Carlo samples. Scaffolding has a consistently strong effect across student populations, STEM (science, technology, engineering, and mathematics) …


Live Long And Prosper: Plant–Soil Feedback, Lifespan, And Landscape Abundance Covary, Andrew Kulmatiski, Karen H. Beard, Jeanette M. Norton, Justin Heavilin, Leslie E. Forero, Josephine Grenzer Dec 2017

Live Long And Prosper: Plant–Soil Feedback, Lifespan, And Landscape Abundance Covary, Andrew Kulmatiski, Karen H. Beard, Jeanette M. Norton, Justin Heavilin, Leslie E. Forero, Josephine Grenzer

Wildland Resources Faculty Publications

Plant soil feedbacks (PSFs) are thought to be important to plant growth and species coexistence, but most support for these hypotheses is derived from short-term greenhouse experiments. Here we use a seven-year, common garden experiment to measure PSFs for seven native and six nonnative species common to the western United States. We use these long-term, field-based estimates to test correlations between PSF and plant landscape abundance, species origin, functional type, and lifespan. To assess potential PSF mechanisms, we also measured soil microbial community composition, root biomass, nitrogen cycling, bulk density, penetration resistance, and shear strength. Plant abundance on the landscape …


A Customized Quantitative Pcr Microrna Panel Provides A Technically Robust Context For Studying Neurodegenerative Disease Biomarkers And Indicates A High Correlation Between Cerebrospinal Fluid And Choroid Plexus Microrna Expression, Wang-Xia Wang, David W. Fardo, Gregory A. Jicha, Peter T. Nelson Dec 2017

A Customized Quantitative Pcr Microrna Panel Provides A Technically Robust Context For Studying Neurodegenerative Disease Biomarkers And Indicates A High Correlation Between Cerebrospinal Fluid And Choroid Plexus Microrna Expression, Wang-Xia Wang, David W. Fardo, Gregory A. Jicha, Peter T. Nelson

Sanders-Brown Center on Aging Faculty Publications

MicroRNA (miRNA) expression varies in association with different tissue types and in diseases. Having been found in body fluids including blood and cerebrospinal fluid (CSF), miRNAs constitute potential biomarkers. CSF miRNAs have been proposed as biomarkers for neurodegenerative diseases; however, there is a lack of consensus about the best candidate miRNA biomarkers and there has been variability in results from different research centers, perhaps due to technical factors. Here, we sought to optimize technical parameters for CSF miRNA studies. We examined different RNA isolation methods and performed miRNA expression profiling with TaqMan® miRNA Arrays. More specifically, we developed a customized …


Amake: Cached Builds Of Top-Level Targets, Jim Buffenbarger Dec 2017

Amake: Cached Builds Of Top-Level Targets, Jim Buffenbarger

Computer Science Faculty Publications and Presentations

This paper describes a software-build tool named Amake, an extension of GNU Make. Its additional features solve important problems that have, until now, only been addressed by “high-end” build tools (e.g., ClearCase and Vesta).

With a typical build tool, if a top-level target must be updated, intermediate targets must be built from sources, and then combined to build the top-level target. The enhancements described here allow a top-level target to be fetched from a shared cache, without building, or even fetching its intermediate-target dependencies. Thus, a developer’s workspace may need only contain sources and top-level targets. This reduces build time, …


Mechanical Specific Energy Versus Depth Of Cut In Rock Cutting And Drilling, Yaneng Zhou, Wu Zhang, Isaac Gamwo, Jeen Shang Lin Dec 2017

Mechanical Specific Energy Versus Depth Of Cut In Rock Cutting And Drilling, Yaneng Zhou, Wu Zhang, Isaac Gamwo, Jeen Shang Lin

Faculty Publications

The relationship between Mechanical Specific Energy (MSE) and the Rate of Penetration (ROP), or equivalently the depth of cut per revolution, provides an important measure for strategizing a drilling operation. This study explores how MSE evolves with depth of cut, and presents a concerted effort that encompasses analytical, computational and experimental approaches. A simple model for the relationship between MSE and cutting depth is first derived with consideration of the wear progression of a circular cutter. This is an extension of Detournay and Defourny's phenomenological cutting model. Wear is modeled as a flat contact area at the bottom of a …


Using Multiple Intelligence Theory To Aid In Reading Comprehension, Kelsy Neil Dec 2017

Using Multiple Intelligence Theory To Aid In Reading Comprehension, Kelsy Neil

Theses/Capstones/Creative Projects

The main purpose of this study is to determine if using Howard Gardner’s Multiple Intelligences Theory to guide activities for literature groups aids in student comprehension. Students in three literature groups at the fifth and sixth grade level were given a survey to determine each student’s intelligence scores. After each student’s intelligence scores were found, the average of each intelligence score was used to determine the groups’ strongest and weakest intelligences. Activities were then made for each group to correlate with their strongest and weakest intelligences and comprehension was tested after each reading assignment and activity was completed via a …


Nucleobase Sublimation On Mammut Americanum Tusk Fragments, Joshua Prybil Dec 2017

Nucleobase Sublimation On Mammut Americanum Tusk Fragments, Joshua Prybil

Mastodon Tusk Project Posters

Many preservation attempts have been made on the tusk that the University of Northern Iowa acquired. Due to the poor preservation attempts a lot of damage has happened and has caused the tusk to be in a way of disrepair. The Carver grant is very keen on the future preservation of the tusk. The sublimation of nucleobases will be able to help guide the type of preservation methods used in order to preserve the nucleobases and possible DNA still in the tusk. The extraction of nucleobases will not only help with the future preservation of tusk but it will also …


Determination And Quantification Of Lead Content In Mammut Americanus Dentine Material By Anodic Stripping Voltammetry, Emma R. Shipley Dec 2017

Determination And Quantification Of Lead Content In Mammut Americanus Dentine Material By Anodic Stripping Voltammetry, Emma R. Shipley

Mastodon Tusk Project Posters

A 120,000-200,000 year old mastodon tusk of species Mammut americanus, recovered from Hampton, Iowa in 1933 (right) was tested for lead using a lead test from Home Depot.1 The lead test was returned positive, so Anodic Stripping Voltammetry (ASV) was undertaken to determine the concentration of lead in the dentine material of the tusk. The lead concentration is of interest because lead could affect both the health of the conservator and researchers and also inform about the diet of the mastodon. Tusk dentine material (left) functions similarly to human teeth, and studies have shown that 90% of lead in the …


Removal Of Varnish Layers Verifying With Uv-Vis Spectroscopy, Vaughn Koch, Treasure Divis Dec 2017

Removal Of Varnish Layers Verifying With Uv-Vis Spectroscopy, Vaughn Koch, Treasure Divis

Mastodon Tusk Project Posters

According to the Roy J. Carver grant, one of the goals is to get the mastodon tusk back to its original state. The preservation methods have not been well documented, therefore determining what the best solvents to remove the different layers needs to be known. In order to do this, various solvents will be used and confirmed through UV-vis spectroscopy with a Diffuse Reflectance Accessory (DRA) attached. This will measure the percentage of light that gets reflected back towards the detector. The image to the left shows the various layers that have been used in preserving the tusk, including some …


Quantitative Evaluation Of Heavy Metals In The Mastodon Tusk Ivory By Atomic Absorption Spectroscopy, Dmytro V. Kravchuck, Linda L. Wilson Dec 2017

Quantitative Evaluation Of Heavy Metals In The Mastodon Tusk Ivory By Atomic Absorption Spectroscopy, Dmytro V. Kravchuck, Linda L. Wilson

Mastodon Tusk Project Posters

One of the most important objects in the University of Northern Iowa Museum collection is the Mammut Americanum (American Mastodon) tusk, which was originally found in 1933 in a sand pit south of Hampton, Iowa. Since then, severe mechanical and chemical damage was done to the tusk in attempts of restoration and storage, as shown in Figure 1. In order to address these problems, the UNI Museum was awarded a Roy J. Carver Charitable Trust Grant to restore and preserve the American Mastodon tusk. The purpose of the project is quantitative determination of the heavy metal content in the core …


Classification Of Tusk Layers By Means Of Raman Spectroscopy, Treasure Divis, Vaughn Koch Dec 2017

Classification Of Tusk Layers By Means Of Raman Spectroscopy, Treasure Divis, Vaughn Koch

Mastodon Tusk Project Posters

The American Mastodon tusk was donated to the University of Northern Iowa, and Dr. J. Cable took the lead on preserving it for museum display at UNI. Dr. Cable’s notes stated that it would be possible to preserve the entire tusk, because the outside was “covered with a hard enamel-like substance”. Some notes were taken as to what materials were used to preserve the tusk early on, but their exact composition was not noted.

• Glazed and varnished between 1933 and 1960

• 1960 – canned patching plaster on chipping areas, glazing liquid (brown), two coats of varnish (satin finish …


What Is The Red Plaster In The Mastodon Tusk?, Tray Hickie Dec 2017

What Is The Red Plaster In The Mastodon Tusk?, Tray Hickie

Mastodon Tusk Project Posters

During the first visit to the tusk, Dr. Sebree found the crack that had been filled with a strange plaster that was not known at the time.

After seeing the plaster glow from the small flashlight Dr. Sebree had with him, identifying this material seemed like an interesting project.

Due to the fact that the plaster’s makeup is unknown, but identifying the material it was made of, future attempts to restore and preserve the fossil can be done more safely in the event that the material is harmful

Initial x-ray analysis of the mastodon tusk revealed many unexpected surprises.

In …


Carbonization Studies On Mammut Americanum Tusk, Nina Jocic Dec 2017

Carbonization Studies On Mammut Americanum Tusk, Nina Jocic

Mastodon Tusk Project Posters

Many preservation attempts have been made on the tusk that the University of Northern Iowa acquired. Due to the poor preservation attempts a lot of damage has happened and has caused the tusk to be in a way of disrepair. The Carver grant is very keen on the future preservation of the tusk. The sublimation of nucleobases will be able to help guide the type of preservation methods used in order to preserve the nucleobases and possible DNA still in the tusk. The extraction of nucleobases will not only help with the future preservation of tusk but it will also …


Fluorescent Surface Mapping Of Mastodon Tusk, Clare Laubenthal, Joshua Sebree Dec 2017

Fluorescent Surface Mapping Of Mastodon Tusk, Clare Laubenthal, Joshua Sebree

Mastodon Tusk Project Posters

The subject of study is a Mammut americanum (American Mastodon) tusk. The tusk is currently damaged and in need of repair. To better understand the tusk and the preservation materials previously used, fluorescence spectrometry was used to make a surface map of the tusk. This data will be useful to the conservationists as they plan the care and restoration of the tusk.