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2019

University of Arkansas, Fayetteville

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Full-Text Articles in Engineering

Load Flow Analysis Of 138/69kv Substation Using Electrical Transient & Analysis Program (Etap), Vanessa Abadia Gomez Dec 2019

Load Flow Analysis Of 138/69kv Substation Using Electrical Transient & Analysis Program (Etap), Vanessa Abadia Gomez

Electrical Engineering Undergraduate Honors Theses

This paper examines the load flow analysis of a high-voltage substation using ETAP, and explores options for improving the voltage profile of the system. This study yields critical information about the system, such as the voltage drop at each feeder, the voltage at each bus, as well as real and reactive power losses at the different branches and feeders. In this power flow examination, the system’s performance is evaluated for different operating conditions, so that control measurements can be applied if necessary. The experimental results are used for proposing a plan of using fixed and switched shunt capacitor banks ...


Generation Of A Ccl2 Knockout Using Crispr/Cas9 And Lipid Mediated Transfection In Ct-26 Murine Colon Carcinoma Cells, Emma Sullivan Aug 2019

Generation Of A Ccl2 Knockout Using Crispr/Cas9 And Lipid Mediated Transfection In Ct-26 Murine Colon Carcinoma Cells, Emma Sullivan

Biomedical Engineering Undergraduate Honors Theses

CCL2 is an inflammatory mediator that is released by tumor cells to activate and direct immune cell species, especially macrophages, to inflammatory sites within the body. The goal of this project was to successfully generate knockout the CCL2 ligand gene using a CRISPR/Cas9 complex delivered via lipid mediated transfection. The sgRNA and Cas9 mRNA were introduced into the cells via lipid-mediated transfection. The cells were incubated for 4 days, before being analyzed using PCR and gel electrophoresis. We expected to see one band on the first gel and two bands on the second gel. Two bands appeared on the ...


Bioengineering Extracellular Matrix Scaffolds For Volumetric Muscle Loss, Kevin Roberts Aug 2019

Bioengineering Extracellular Matrix Scaffolds For Volumetric Muscle Loss, Kevin Roberts

Theses and Dissertations

Volumetric muscle loss overwhelms skeletal muscle’s ordinarily capable regenerative machinery, resulting in fibrosis and severe functional deficits which have defied clinical repair strategies. My work spans the design and preclinical evaluation of implants intended to drive the cell community of injured muscle toward a regenerative state, as well as the development of an understanding of the molecular responses of this cell community to biomaterial interventions. I demonstrate a new class of biomaterial by leveraging the productive capacity of sacrificial hollow fiber membrane cell culture; I show specifically that unique threads of whole extracellular matrix can be isolated by solvent ...


Investigation Of The Effect Of Age On Regenerative Outcomes Following Treatment Of Volumetric Muscle Loss Injuries, John Taehwan Kim Aug 2019

Investigation Of The Effect Of Age On Regenerative Outcomes Following Treatment Of Volumetric Muscle Loss Injuries, John Taehwan Kim

Theses and Dissertations

Volumetric muscle loss (VML) is a traumatic injury in skeletal muscle resulting in the bulk loss of more than 20% of the muscle’s volume. Included in the bulk loss of muscle is the skeletal muscle niche comprised of nerve bundles, vasculature, local progenitor cells, basal lamina, and muscle fibers, overwhelming innate repair mechanisms. The hallmark of VML injury is the excessive accumulation of non-contractile, fibrotic tissue and permanent functional deficits. Though predominant in the younger demographic, the elderly population is also captured within VML injuries. There are many factors that change with aging in skeletal muscle that may further ...


Development Of A Ground-Based Aerial-Tracking Instrument For Open-Path Spectroscopy To Monitor Atmospheric Constituents, Haden Hodges Aug 2019

Development Of A Ground-Based Aerial-Tracking Instrument For Open-Path Spectroscopy To Monitor Atmospheric Constituents, Haden Hodges

Civil Engineering Undergraduate Honors Theses

A ground-based aerial-tracking instrument, known as the Ground Tracker, designed to provide spectral data to quantify greenhouse gases is under development. The Ground Tracker includes an Optical System including a high power rifle scope, video camera, and spectrometer used to locate an active light source from the Emitter, and collect spectral data by utilizing an actuating mirror. The implementation of this instrument could be made low cost by utilizing existing weather balloon infrastructure to allow the Emitter to be placed into the lower stratosphere. The recovery of the emitter will be possible by tracking the GPS coordinates. Weather balloon instrument ...


Displacement Derived Energy Levels For Harvard Miniature Compaction, Ana Laura Errigo, Julia Loshelder Aug 2019

Displacement Derived Energy Levels For Harvard Miniature Compaction, Ana Laura Errigo, Julia Loshelder

Civil Engineering Undergraduate Honors Theses

Previously, the amount of energy provided by the Harvard Miniature tamper was adjusted by changing the number of blows per lift or the number of lifts or was not adjusted at all. However, this research was conducted to investigate the effect of adjusting the displacement of the spring (increased or decreased) to change the potential energy of the spring and therefore change the compacive effort with a specific type of soil. Thus, the objective was to match the compaction energies using the Harvard miniature method with the compaction energies obtained using the Proctor method. Specifically, the goal was to show ...


Five-Level Flying Capacitor Converter Used As A Static Compensator For Current Unbalances In Three-Phase Distribution Systems, Rafael Franceschi Aug 2019

Five-Level Flying Capacitor Converter Used As A Static Compensator For Current Unbalances In Three-Phase Distribution Systems, Rafael Franceschi

Theses and Dissertations

This thesis presents and evaluates a solution for unbalanced current loading in three-phase distribution systems. The proposed solution uses the flying capacitor multilevel converter as its main topology for an application known as Unbalanced Current Static Compensator. The fundamental theory, controller design and prototype construction will be presented along with the experimental results. The Unbalanced Current Static Compensator main objective is the balancing of the up-stream currents from the installation point to eliminate the negative- and zero-sequence currents originated by unbalanced single-phase loads.

Three separate single-phase flying capacitor converters are controlled independently using a d-q rotating reference frame algorithm to ...


Feedforward And Feedback Signals In The Olfactory System, Srimoy Chakraborty May 2019

Feedforward And Feedback Signals In The Olfactory System, Srimoy Chakraborty

Theses and Dissertations

The conglomeration of myriad activities in neural systems often results in prominent oscillations. The primary goal of the research presented in this thesis was to study effects of sensory stimulus on the olfactory system of rats, focusing on the olfactory bulb (OB) and the anterior piriform cortex (aPC). Extracellular electrophysiological measurements revealed distinct frequency bands of oscillations in OB and aPC. However, how these oscillatory fluctuations help the animal to process sensory input is not clearly understood. Here we show high frequency oscillations in olfactory bulb carry feedforward signals to anterior piriform cortex whereas feedback from the aPC is predominantly ...


Predicting The Mechanical Properties Of Nanocomposites Reinforced With 1-D, 2-D And 3-D Nanomaterials, Scott Edward Muller May 2019

Predicting The Mechanical Properties Of Nanocomposites Reinforced With 1-D, 2-D And 3-D Nanomaterials, Scott Edward Muller

Theses and Dissertations

Materials with features at the nanoscale can provide unique mechanical properties and increased functionality when included as part of a nanocomposite. This dissertation utilizes computational methods at multiple scales, including molecular dynamics (MD) and density functional theory (DFT), and the coupled atomistic and discrete dislocation multiscale method (CADD), to predict the mechanical properties of nanocomposites possessing nanomaterials that are either 1-D (carbyne chains), 2-D (graphene sheets), or 3-D (Al/amorphous-Si core-shell nanorod).

The MD method is used to model Ni-graphene nanocomposites. The strength of a Ni-graphene nanocomposite is found to improve by increasing the gap between the graphene sheet and ...


Fault Adaptive Workload Allocation For Complex Manufacturing Systems, Charlie B. Destefano May 2019

Fault Adaptive Workload Allocation For Complex Manufacturing Systems, Charlie B. Destefano

Theses and Dissertations

This research proposes novel fault adaptive workload allocation (FAWA) strategies for the health management of complex manufacturing systems. The primary goal of these strategies is to minimize maintenance costs and maximize production by strategically controlling when and where failures occur through condition-based workload allocation.

For complex systems that are capable of performing tasks a variety of different ways, such as an industrial robot arm that can move between locations using different joint angle configurations and path trajectories, each option, i.e. mission plan, will result in different degradation rates and life-expectancies. Consequently, this can make it difficult to predict when ...


Hardware Ip Classification Through Weighted Characteristics, Brendan Mcgeehan May 2019

Hardware Ip Classification Through Weighted Characteristics, Brendan Mcgeehan

Theses and Dissertations

Today’s business model for hardware designs frequently incorporates third-party Intellectual Property (IP) due to the many benefits it can bring to a company. For instance, outsourcing certain components of an overall design can reduce time-to-market by allowing each party to specialize and perfect a specific part of the overall design. However, allowing third-party involvement also increases the possibility of malicious attacks, such as hardware Trojan insertion. Trojan insertion is a particularly dangerous security threat because testing the functionality of an IP can often leave the Trojan undetected. Therefore, this thesis work provides an improvement on a Trojan detection method ...


Asynchronous Circuit Synthesis Using Multi-Threshold Null Convention Logic, Nicholas Renoudet Mize May 2019

Asynchronous Circuit Synthesis Using Multi-Threshold Null Convention Logic, Nicholas Renoudet Mize

Theses and Dissertations

As the demand for an energy-efficient alternative to traditional synchronous circuit design grows, hardware designers must reconsider the traditional clock tree. By doing away with the constrains of a clock, asynchronous sequential circuit designs can achieve a much greater level of efficiency. The utilization of asynchronous logic synthesis flows has enabled researchers to better implement asynchronous circuit designs which have been optimized using the same industry standard tools that are already used in sequential synchronous designs. This thesis offers a new flow for such tools which implements the MTNCL asynchronous circuit architecture.


Towards A Prototype Platform For Ros Integrations On A Ground Robot, Taylor Joseph Linville Whitaker May 2019

Towards A Prototype Platform For Ros Integrations On A Ground Robot, Taylor Joseph Linville Whitaker

Theses and Dissertations

The intent of this work was to develop, evaluate, and demonstrate a prototype robot platform on which ROS integrations could be explored. With observations of features and requirements of existing industrial and service mobile ground robots, a platform was designed and outfitted with appropriate components to enable the most common operational-critical functionalities and account for unforeseen components and features. The resulting Arlo Demonstration Robot accommodates basic mapping, localization, and navigation in both two and three-dimensional space as well as additional safety and teleoperation features. The control system is centered around the Zybo Z7 FPGA SoC hosting a custom hardware design ...


Plasmonic Properties Of Nanoparticle And Two Dimensional Material Integrated Structure, Desalegn Tadesse Debu May 2019

Plasmonic Properties Of Nanoparticle And Two Dimensional Material Integrated Structure, Desalegn Tadesse Debu

Theses and Dissertations

Recently, various groups have demonstrated nano-scale engineering of nanostructures for optical to infrared wavelength plasmonic applications. Most fabrication technique processes, especially those using noble metals, requires an adhesion layer. Previously proposed theoretical work to support experimental measurement often neglect the effect of the adhesion layers. The first finding of this work focuses on the impact of the adhesion layer on nanoparticle plasmonic properties. Gold nanodisks with a titanium adhesion layer are investigated by calculating the scattering, absorption, and extinction cross-section with numerical simulations using a finite difference time domain (FDTD) method. I demonstrate that a gold nanodisk with an adhesive ...


Using Peripheral Venous Pressure Waveforms To Predict Key Hemodynamic Parameters, Ali Zohair A Alalawi May 2019

Using Peripheral Venous Pressure Waveforms To Predict Key Hemodynamic Parameters, Ali Zohair A Alalawi

Theses and Dissertations

Analysis of peripheral venous pressure (PVP) waveforms is a novel method of monitoring intravascular volume. Two cohorts were used to study the hemodynamics change of the body state and its influence on the PVP using (1) dehydration setting with infants suffering from pyloric stenosis and (2) hemorrhage setting during a craniosynostosis elective surgery. The goal of this research is to develop a minimally invasive method of analyzing the PVP waveforms and find correlations with volume loss.

Twenty-three pyloric stenosis patients PVP were acquired at five stages and were divided into euvolemic, normal fluid volume, and hypovolemic, significant fluid loss. Seven ...


Motor Control Systems Analysis, Design, And Optimization Strategies For A Lightweight Excavation Robot, Austin Jerold Crawford May 2019

Motor Control Systems Analysis, Design, And Optimization Strategies For A Lightweight Excavation Robot, Austin Jerold Crawford

Theses and Dissertations

This thesis entails motor control system analysis, design, and optimization for the University of Arkansas NASA Robotic Mining Competition robot. The open-loop system is to be modeled and simulated in order to achieve a desired rapid, yet smooth response to a change in input. The initial goal of this work is to find a repeatable, generalized step-by-step process that can be used to tune the gains of a PID controller for multiple different operating points. Then, sensors are to be modeled onto the robot within a feedback loop to develop an error signal and to make the control system self-corrective ...


Investigating Virus Clearance Via Ph Inactivation During Biomanufacturing, Wenbo Xu May 2019

Investigating Virus Clearance Via Ph Inactivation During Biomanufacturing, Wenbo Xu

Biomedical Engineering Undergraduate Honors Theses

In the processing of biopharmaceuticals, viral clearance and viral safety are important for the development of monoclonal antibodies. Murine xenotropic leukemia virus (XMuLV) is one of the retroviruses, recommended by Food and Drug Administration (FDA) as a model virus for viral clearance via inactivation from therapeutics derived from Chinese hamster ovary cells (CHO). A robust and effective method was investigated to clear or inactivate endogenous viruses by low pH inactivation. The effects of different conductivity and inactivated time on XMuLV clearance was determined. Acetate buffer was prepared with different conductivity, and 2% XMuLV was spiked into acetate buffer. XMuLV virus ...


A Bioinstrumentation Active Learning Educational Module: The Design Of A Working Temperature Sensor Using A Ntc Thermistor, Baylor Bush May 2019

A Bioinstrumentation Active Learning Educational Module: The Design Of A Working Temperature Sensor Using A Ntc Thermistor, Baylor Bush

Biomedical Engineering Undergraduate Honors Theses

The Department of Biomedical Engineering at the University of Arkansas has continued to develop over the years, with more students enrolling in the program each year. Within the first biomedical engineering course, Introduction to Biomedical Engineering, various topics are introduced to students, and the topic of bioinstrumentation has been one of the most complex and difficult topics for students to comprehend through just a few lectures. In order to aid students in grasping these intricate concepts, an active learning module was developed in which students can work in groups to build a simple thermistor circuit as a temperature sensor. The ...


Autonomous Boat Control Software Design Using Model-Based Systems Engineering, Noah Nelson May 2019

Autonomous Boat Control Software Design Using Model-Based Systems Engineering, Noah Nelson

Electrical Engineering Undergraduate Honors Theses

While there is considerable buzz about self-driving cars, self-driving boats are actually more fully developed. The Boat Hardware Control Platform Team was tasked with developing a fleet of small autonomous boats that travel to a destination while avoiding obstacles and staying in formation. The author’s specific task was to develop software used by the boats to detect obstacles and plan a route to a destination. This was done using a method inspired by self-driving cars, which shows promise, but is still being tested at the time of writing. The entire project incorporated model-based systems engineering, which proved to be ...


Design Of Two-Stage Operational Amplifier Using Indirect Feedback Frequency Compensation, Roderick Gomez May 2019

Design Of Two-Stage Operational Amplifier Using Indirect Feedback Frequency Compensation, Roderick Gomez

Electrical Engineering Undergraduate Honors Theses

This thesis work details the designing process of two silicon two-stage operational amplifiers with indirect feedback compensation and with Miller compensation technique. The main objective of this thesis is to study the advantages of indirect feedback compensation in comparison with Miller compensation and how this technique can be applied to meet certain design specifications. The operational amplifiers are designed with 130 nm Silicon Germanium CMOS process ideally for temperature range of 25°C to 300°C. The two op-amps are designed to have a DC gain of about 70 dB and 60 degrees of phase margin. The indirect feedback compensation ...


Designing A Solar Pv System To Power A Single-Phase Distribution System, Ana Guerra Vega May 2019

Designing A Solar Pv System To Power A Single-Phase Distribution System, Ana Guerra Vega

Electrical Engineering Undergraduate Honors Theses

Over the last decade, the costs of PV system components have dropped more than 70%. Additionally, green energy incentives like the 30% tax credit have been pushed forward. PV solar systems have become accessible to the general public. Companies are pledging to reduce their carbon emissions.

As part of their green initiative, the City of Fayetteville has requested a feasibility study for a PV system to be installed on the rooftop of the Facilities Management building, 115 S. Church Ave, Fayetteville, AR, 72701. This thesis shows the design process of this PV system and the return on investment estimation. While ...


Recovery Of Water And Salt From Hyper-Saline Mine Water Using Freeze Crystallization, Clara Somerville May 2019

Recovery Of Water And Salt From Hyper-Saline Mine Water Using Freeze Crystallization, Clara Somerville

Chemical Engineering Undergraduate Honors Theses

The Freezerbacks researched, designed, and economically evaluated a full-scale freeze crystallization process as well as two alternative full-scale processes: 5 stage multiple effect evaporation and reverse osmosis. All three processes were designed to treat hyper-saline mine water that was sent into evaporation pond systems. These systems were designed for Freeport-McMoRan’s mines that need to treat impacted water.

The Freeport-McMoRan copper mine in Miami, Arizona was visited in order to gain insight about the problem. The mine is no longer actively mining copper and is in the process of reclaiming land used. An essential part of restoring the land is ...


Recovery Of Water And Salts From Hyper-Saline Mine Water Using Freeze Crystallization, Miriam Gonzalez May 2019

Recovery Of Water And Salts From Hyper-Saline Mine Water Using Freeze Crystallization, Miriam Gonzalez

Chemical Engineering Undergraduate Honors Theses

In the mining industry, usage of large volumes of water enables mines to conduct multiple processes within one location. Hypersaline brine waters exit the processes of the mine to be utilized for other roles; some of these roles include leaching, recirculation, and extraction operations. These waters are highly concentrated with salt components and are released to different sections of the mine. The salts of highest concentration in the brine are aluminum sulfate and magnesium sulfate heptahydrate, along with low concentrations of many other elements. There are multiple ways to recover purified water from the brine solution: freeze crystallization, evaporative processes ...


Desalination: Freeze Crystallization, Ibrahim Guiga May 2019

Desalination: Freeze Crystallization, Ibrahim Guiga

Chemical Engineering Undergraduate Honors Theses

The Freezerbacks researched, designed, and economically evaluated a full-scale freeze crystallization process as well as two alternative full-scale processes: 5 stage multiple effect evaporation and reverse osmosis. All three processes were designed to treat hyper-saline mine water that was sent into evaporation pond systems. These systems were designed for Freeport-McMoRan’s mines that need to treat impacted water.

The Freeport-McMoRan copper mine in Miami, Arizona was visited in order to gain insight about the problem. The mine is no longer actively mining copper and is in the process of reclaiming land used. An essential part of restoring the land is ...


Recovery Of Water And Salt From Hyper-Saline Mine Water Using Freeze Crystallization, Gabrielle Casey May 2019

Recovery Of Water And Salt From Hyper-Saline Mine Water Using Freeze Crystallization, Gabrielle Casey

Chemical Engineering Undergraduate Honors Theses

The Freezerbacks researched, designed, and economically evaluated a full-scale freeze crystallization process as well as two alternative full-scale processes: 5 stage multiple effect evaporation and reverse osmosis. All three processes were designed to treat hyper-saline mine water that was sent into evaporation pond systems. These systems were designed for Freeport-McMoRan’s mines that need to treat impacted water.

The Freeport-McMoRan copper mine in Miami, Arizona was visited in order to gain insight about the problem. The mine is no longer actively mining copper and is in the process of reclaiming land used. An essential part of restoring the land is ...


Removal And Reuse Of Phosphorus As A Fertilizer From Cafo Runoff, Kristin Moore May 2019

Removal And Reuse Of Phosphorus As A Fertilizer From Cafo Runoff, Kristin Moore

Chemical Engineering Undergraduate Honors Theses

Eutrophication is the process in which nutrient saturated waters promote algal blooms on the surface of the water. This limits the amount of dissolved oxygen content in the water, effectively limiting the range of species that can survive in a body of water. Concentrated animal feeding operations (CAFO) can contribute to this issue. The animals in a CAFO produce large amounts of nutrient-rich waste streams that can enter natural waterways if not properly managed and increase the problem of eutrophication. The ability to treat these waste streams and recover the excess nutrients would allow for not only the reduction of ...


Removal And Reuse Of Phosphorus As A Fertilizer From Cafo Runoff, Hannah Young May 2019

Removal And Reuse Of Phosphorus As A Fertilizer From Cafo Runoff, Hannah Young

Chemical Engineering Undergraduate Honors Theses

Eutrophication is the process in which nutrient saturated waters promote algal blooms on the surface of the water. This limits the amount of dissolved oxygen content in the water, effectively limiting the range of species that can survive in a body of water. Concentrated animal feeding operations (CAFO) can contribute to this issue. The animals in a CAFO produce large amounts of nutrient-rich waste streams that can enter natural waterways if not properly managed and increase the problem of eutrophication. The ability to treat these waste streams and recover the excess nutrients would allow for not only the reduction of ...


Silver-Based Microbial Check Valve For Spacecraft Potable Water Systems, Jennifer Gaines May 2019

Silver-Based Microbial Check Valve For Spacecraft Potable Water Systems, Jennifer Gaines

Chemical Engineering Undergraduate Honors Theses

As human space exploration increases, the development of a more efficient potable water treatment system suited for spacecraft becomes crucial. This Waste-management Education Research Consortium (WERC) challenge was designed to explore the viability of microbial control through the utilization of silver ions as a biocide for possible integration into the Tranquility Node 3 water purification system aboard the International Space Station (ISS). Current systems using iodine risk causing hyperthyroidism from overexposure; however, silver can be safely ingested without this side effect. After researching silver delivery methods including electrochemical ion production, controlled release, or a combination of the two, our team ...


Task 1: Silver-Based Microbial Check Valve For Spacecraft Potable Water Systems, Eric Beitle May 2019

Task 1: Silver-Based Microbial Check Valve For Spacecraft Potable Water Systems, Eric Beitle

Chemical Engineering Undergraduate Honors Theses

As human space exploration increases, the development of a more efficient potable water treatment system suited for spacecraft becomes crucial. This Waste-management Education Research Consortium (WERC) challenge was designed to explore the viability of microbial control through the utilization of silver ions as a biocide for possible integration into the Tranquility Node 3 water purification system aboard the International Space Station (ISS). Current systems using iodine risk causing hyperthyroidism from overexposure; however, silver can be safely ingested without this side effect. After researching silver delivery methods including electrochemical ion production, controlled release, or a combination of the two, our team ...


Effect Of Thiols For Nitrogen Reduction To Ammonia, Zakary R. Ford May 2019

Effect Of Thiols For Nitrogen Reduction To Ammonia, Zakary R. Ford

Chemical Engineering Undergraduate Honors Theses

Ammonia is an important chemical used for fertilizers and also a potential carbon-free hydrogen storage medium. The Haber-Bosch process is the main production process, which requires large energy- and capital-input. Therefore, it is crucial to develop an alternate scalable synthesis that provides a less energy intensive and more economical route for synthetic ammonia production. In this paper, a 1Fe1Ni film was functionalized with C3OH and C6OH for the electrochemical synthesis of ammonia. This work will provide some insight into how thiol ligands can increase the selectivity of the catalyst for nitrogen reduction reaction and can be ...