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Gold Standards Training And Evaluator Calibration Of Pilot School Check Instructors, Paul M. Cairns 2021 Embry-Riddle Aeronautical University

Gold Standards Training And Evaluator Calibration Of Pilot School Check Instructors, Paul M. Cairns

PhD Dissertations and Master's Theses

A key component of air carrier advanced qualification programs is the calibration and training of instructors and evaluators and assurance of reliable and valid data in support of such programs. A significant amount of research is available concerning the calibration of air carrier evaluators, but no research exists regarding the calibration of pilot school check instructors. This study was designed to determine if pilot school check instructors can be calibrated against a gold standard to perform reliable and accurate evaluations. Calibration followed the principles and theories of andragogy and adult learning and teaching, including emphasis on the cognitive domain of ...


Involvement Of The Ino80 Chromatin Remodeling Complex In Cell Division And Genomic Stability, Ethan Chen 2021 University of Arkansas, Fayetteville

Involvement Of The Ino80 Chromatin Remodeling Complex In Cell Division And Genomic Stability, Ethan Chen

Biomedical Engineering Undergraduate Honors Theses

Cell division is a vital biological process for growth and development in both single and multi-cellular organisms—whereby the cell must duplicate its organelles and genome in entirety and appropriately distribute the copied contents to the daughter cells. Cells undergo a cycle of two distinct phases: interphase and mitosis. During interphase, the cell replicates its genomic DNA (in the form of chromosomes) located within the nucleus. DNA replication is carried out in a euchromatin state, where the chromosome structure is loose and easily accessible by DNA polymerase and other replication enzymes. Upon the completion of replication, chromatin is condensed into ...


Guide Rnas Preparation For In-Vitro Crispr-Cas9 Complex Delivery Targeting Genes That Affect Wound Healing., Prashant Khatiwada 2021 University of Arkansas, Fayetteville

Guide Rnas Preparation For In-Vitro Crispr-Cas9 Complex Delivery Targeting Genes That Affect Wound Healing., Prashant Khatiwada

Biomedical Engineering Undergraduate Honors Theses

CRISPR-Cas9 technology has widely been used as a viable genome engineering platform to make site-specific insertion, deletion, and breaks. The nuclease dead version of Cas9 or dCas9 can be used for the activation and repression of target gene sites using specific activation or repression domains. In this study, CRISPR guide RNAs were designed for a CRISPR inhibition approach to repress the transcriptional activity of the target genes. An expression plasmid vector composed of a U6 promoter sequence, BbsI restriction sites, and a chimeric gRNA sequence was digested, and the phosphorylated forward and reverse gRNAs were ligated with the plasmid vector ...


Modulation And Long-Term Release Of Cardiac Fibroblast Secretome To Enhance Cardiac Cell Survival Under Hypoxia, JIN ZHAI 2021 Washington University in St. Louis

Modulation And Long-Term Release Of Cardiac Fibroblast Secretome To Enhance Cardiac Cell Survival Under Hypoxia, Jin Zhai

Engineering and Applied Science Theses & Dissertations

The irreversible damage to the heart caused by myocardial infarction (MI) leads to over one million deaths in the United States every year. There are several approaches to treat MI, such as angioplasty, redirected blood flow, and electrical medical devices, but they cannot promote new cardiac tissue generation, thus leading to potential high risk of re-surgeries. To overcome this limitation, stem cell therapy is regarded as a promising method. However, the implantation of stem cells has ethical and safe concern and the efficiency is limited due to low cell engraftment. Moreover, the effect of stem cell is predominantly attributed to ...


Development Of An Integrated Salt Cartridge-Reverse Electrodialysis (Red) Device To Increase Electrolyte Concentrations Of Human Blood Flow To Power Biomedical Devices, Caroline Campbell 2021 University of Arkansas, Fayetteville

Development Of An Integrated Salt Cartridge-Reverse Electrodialysis (Red) Device To Increase Electrolyte Concentrations Of Human Blood Flow To Power Biomedical Devices, Caroline Campbell

Chemical Engineering Undergraduate Honors Theses

Emerging technologies in nanotechnology and biomedical sciences have led to an increase in biomedical implantable devices including cardiac pacemakers, artificial organs, drug pumps, and sensors. These devices require continuous stable and reliable power to operate, which creates the demand for the need to find a safe, reliable, and stable power source. A promising avenue for a power source for these devices is a miniaturized reverse electrodialysis (RED) biopower cell design that utilizes the salinity differences between bloodstreams that flow inside the human body. Initial results of the RED system demonstrate that higher gradient salinity differences between streams lead to a ...


Garver Industrial Design Project: Designing A Full-Scale Reverse Osmosis Water Treatment Facility For The City Of Lawton, Oklahoma, Kayliana Warden, Marlando Collins, Sandrina DePaz, Reid Eakin, Reed Leasure, Vera Rodriguez 2021 University of Arkansas, Fayetteville

Garver Industrial Design Project: Designing A Full-Scale Reverse Osmosis Water Treatment Facility For The City Of Lawton, Oklahoma, Kayliana Warden, Marlando Collins, Sandrina Depaz, Reid Eakin, Reed Leasure, Vera Rodriguez

Chemical Engineering Undergraduate Honors Theses

A groundwater treatment facility was designed for Lawton, Oklahoma to address potential water scarcity due to drought conditions in southwest Oklahoma. The facility will produce five million gallons per day (MGD) of treated water. The plant will have the capacity of treating 4,085 gallons per minute of influent water at an 86% recovery. The water to be treated will come from the Arbuckle-Timbered Hills Aquifer. Studies have been conducted around the aquifer to identify the best well site locations.

A centralized treatment facility using reverse osmosis filtration as the main treatment technology has been designed. To prevent reverse osmosis ...


Economic Feasibility Of Mixed Plastic Waste Pyrolysis Using Twin Reactor System In Northwest Arkansas, Carol Rogers, Patricia Means, Renato Gonzalez, Kaida Sheets, Hayden Townsend 2021 University of Arkansas, Fayetteville

Economic Feasibility Of Mixed Plastic Waste Pyrolysis Using Twin Reactor System In Northwest Arkansas, Carol Rogers, Patricia Means, Renato Gonzalez, Kaida Sheets, Hayden Townsend

Chemical Engineering Undergraduate Honors Theses

Plastic waste generation is increasing at an unsustainable rate while recycling solutions remain stagnant. As a chemical means of recycling, mixed plastic waste pyrolysis can generate synthetic oil appropriate for use as fuel in power generation from plastic waste that otherwise accumulates in landfills. With the scaling of a commercial plastic pyrolysis process in Northwest Arkansas (NWA) modeled after an operational sawdust pyrolysis unit in Huntsville, Arkansas, economic analysis resulted in 26.3% internal rate of return. Therefore, construction of a commercial mixed plastic-to-fuel pyrolysis plant is economically justified and should be pursued. To effectively implement the proposed design, NWA ...


Computational Investigation Of Perforated Plate Film Cooling Utilizing Conjugate Heat Transfer, Jonathan Sippel 2021 Embry-Riddle Aeronautical University

Computational Investigation Of Perforated Plate Film Cooling Utilizing Conjugate Heat Transfer, Jonathan Sippel

PhD Dissertations and Master's Theses

The accuracy of modern state-of-practice computational fluid dynamics approaches in predicting the cooling effectiveness of a perforated plate film-cooling arrangement is evaluated in ANSYS Fluent. A numerical investigation is performed using the Reynolds Averaged Navier Stokes equations and compared to NASA Glenn’s available Turbulent Heat Flux 4 experimental measurements collected as a part of the Transformational Tools and Technologies Project. A multiphysics approach to model heat conduction through the solid geometry is shown to offer significant improvements in wall temperature and film effectiveness prediction accuracy over the standard adiabatic wall approach. Additionally, localized gradient-based grid adaption is analyzed using ...


Analysis Of Ship Airwakes Using Modal Decomposition, Nicholas Zhu 2021 Embry-Riddle Aeronautical University

Analysis Of Ship Airwakes Using Modal Decomposition, Nicholas Zhu

PhD Dissertations and Master's Theses

The three-dimensional, unsteady, and turbulent airwake produced by a scaled model of a generic Navy ship (Simple Frigate Shape No. 2) was investigated in a low-speed wind tunnel. Stereoscopic, time-resolved particle image velocimetry (TR-PIV) measurements were made at six different crosswise planes over the flight deck region of the ship model, with and without the effect of a simulated atmospheric boundary layer (ABL).

Spatiotemporal analyses of the TR-PIV measurements were performed using modal decomposition, and the modes were decomposed further based on the frequency contents of their time dynamics. This approach allowed an inspection of the individual scales of the ...


Regression Analysis Of Pacing When Running A Marathon, Hawkin Starke 2021 University of Arkansas, Fayetteville

Regression Analysis Of Pacing When Running A Marathon, Hawkin Starke

Industrial Engineering Undergraduate Honors Theses

Regression analysis can be an effective way of examining performance in the marathon event. By splitting up the race into segments or in runner terminology “splits” the significance of each segment as it relates to the total finish time can be explored. Because the idea of splits is already ingrained into the minds of runners, it makes intuitive sense to use these as the metrics to define a race. Additionally, marathons generally make participant age and gender date publicly available which can then be used to find trends within specific demographics. This tailors trends to smaller groups of people, making ...


Improving The Performance Of An Ead Aircraft By Use Of A Retractable Electrode System, Michael Alexander Fredricks 2021 University of Arkansas, Fayetteville

Improving The Performance Of An Ead Aircraft By Use Of A Retractable Electrode System, Michael Alexander Fredricks

Mechanical Engineering Undergraduate Honors Theses

Electroaerodynamic (EAD) propulsion is a growing area of research for small, low powered aircraft. Recent tests of EAD aircraft have demonstrated low performance in unpowered, gliding flight. The purpose of this paper is to investigate the effect of a retractable electrode system on the flight performance of an EAD aircraft. An analysis of electrode drag contribution on the MIT ionic wind plane’s performance predicts a maximum lift to drag ratio of 22, with the addition of a retractable electrode system, for a similarly sized and modeled EAD aircraft. An experiment is developed using a prototype aircraft, launcher, and retraction ...


Investigation Of Bio-Inspired Pin Geometries For Enhanced Heat Transfer Applications, Anish Prasad 2021 Embry-Riddle Aeronautical University

Investigation Of Bio-Inspired Pin Geometries For Enhanced Heat Transfer Applications, Anish Prasad

PhD Dissertations and Master's Theses

Array of circular cylindrical pins or tubes are one of the most widely used type of convection cooling systems, profoundly used in the internal cooling of gas turbine blades. They promote heat transfer due to flow acceleration, secondary flows and wake shedding, at the expense of large pressure loss and unsteadiness in the flow. The need to reduce pressure loss and maintain the heat transfer rates are a much needed requirement for a variety of industries to improve the cooling efficiency. One such prominent line of research is conducted on optimizing the design of the circular cylindrical pins to increase ...


Environmental Impacts Of Overdesign In Small Community Water Resource Recovery Facilities, Andrew Pham 2021 University of Nebraska-Lincoln

Environmental Impacts Of Overdesign In Small Community Water Resource Recovery Facilities, Andrew Pham

Environmental Engineering Theses and Graduate Student Research

Although water resource recovery facilities (WRRFs) reduce environmental impacts related to water quality, their construction and operation result in negative environmental impacts in other categories. Past research into Nebraska WRRFs investigated variables determining energy intensity, opportunities and barriers for energy efficiency improvements, and environmental impacts of the construction and operation phase. This leads to the research question of what design practices can be considered to reduce the environmental impacts.

The Life Cycle Assessment (LCA) methodology was used to evaluate and compare the inventory and environmental impacts of nine small WRRFs, most of which are serving slow growing or declining populations ...


Estimating Irrigation In Rice Fields With A Water Balance Approach, Kristen Trinh 2021 University of Arkansas, Fayetteville

Estimating Irrigation In Rice Fields With A Water Balance Approach, Kristen Trinh

Biological and Agricultural Engineering Undergraduate Honors Theses

Global food production must increase to meet the demand associated with increased population growth, so irrigation water use will continue to rise. Therefore, it is important to monitor water usage particularly when an irrigation flowmeter is unavailable. A field water balance was created for a selection of rice fields in East-central Arkansas under observation in 2018 and 2019. From those, irrigation inputs are deduced from the water balance alone. First, each field had sensors that collected water table level (WTL) data. Next, other water inputs and outputs such as precipitation and evapotranspiration (ET) were collected from two modeled sources. The ...


Data Forgery Detection In Automatic Generation Control: Exploration Of Automated Parameter Generation And Low-Rate Attacks, Yatish R. Dubasi 2021 University of Arkansas, Fayetteville

Data Forgery Detection In Automatic Generation Control: Exploration Of Automated Parameter Generation And Low-Rate Attacks, Yatish R. Dubasi

Computer Science and Computer Engineering Undergraduate Honors Theses

Automatic Generation Control (AGC) is a key control system utilized in electric power systems. AGC uses frequency and tie-line power flow measurements to determine the Area Control Error (ACE). ACE is then used by the AGC to adjust power generation and maintain an acceptable power system frequency. Attackers might inject false frequency and/or tie-line power flow measurements to mislead AGC into falsely adjusting power generation, which can harm power system operations. Various data forgery detection models are studied in this thesis. First, to make the use of predictive detection models easier for users, we propose a method for automated ...


Light Intensity Control For Plc-Based Hydroponic Demonstration System, Christian Hitt 2021 University of Arkansas, Fayetteville

Light Intensity Control For Plc-Based Hydroponic Demonstration System, Christian Hitt

Biological and Agricultural Engineering Undergraduate Honors Theses

In order to demonstrate a skill set obtained through the University of Arkansas Biological Engineering, a group of students and I developed a hydroponic system where plants could be grown in a chamber. System parameters such as air quality, irrigation, and lighting were controlled by a Programmable Logic Computer (PLC) and an array of sensors and actuators. Each student focused on a certain aspect of this system, mine being the lighting. Developing this system involved researching the relationship between light intensity and plant growth, designing a system to suspend the lights above the growth chamber, and develop a system to ...


Design Of Control Logic And The Human-Machine Interface For A Demonstration Plant Growth Chamber Implemented On A Programmable Logic Controller, Rachael Koehler 2021 University of Arkansas, Fayetteville

Design Of Control Logic And The Human-Machine Interface For A Demonstration Plant Growth Chamber Implemented On A Programmable Logic Controller, Rachael Koehler

Biological and Agricultural Engineering Undergraduate Honors Theses

This honors thesis covers the planning, development, and implementation of system controls and human-machine interface (HMI) for a demonstration plant growth chamber. The work is a continuation of an ongoing project to be used as an educational and recruiting tool manifesting the skills acquired from the Biological and Agricultural Engineering Department at the University of Arkansas’ College of Engineering. This work includes emergency controls, overall design interface, and controls for both the aeration and lighting subsystems of the growth chamber. Overall design interface controls established included development of two user modes, Administrator and Visitor. The Administrator user will have full ...


Transimpedance Amplification Of Optocoupler Output For High Temperature Applications, Kara Maurer 2021 University of Arkansas, Fayetteville

Transimpedance Amplification Of Optocoupler Output For High Temperature Applications, Kara Maurer

Electrical Engineering Undergraduate Honors Theses

When looking to the future of electronics, one characteristic is becoming more lucrative: high temperature capabilities. With the goals of not only becoming more efficient electronically, spatially, and cost-wise, adapting electronics for a high temperature environment can potentially be a route to all three of these goals. Not only does it take away the need for a cooling method, but it can also increase the longevity of a product which can make it even more cost effective. In an effort to contribute to the push for high temperature electronics, the University of Arkansas is developing a high temperature power module ...


Designing Cryogenic Strain Device For 2d Materials, Jake Carter 2021 University of Arkansas, Fayetteville

Designing Cryogenic Strain Device For 2d Materials, Jake Carter

Mechanical Engineering Undergraduate Honors Theses

The Churchill lab working within the Physics Department at the University of Arkansas is working to create important quantum states including weak topological insulators (TIs) through the use of symmetry engineering and topological electronic states in two-dimensional (2D) crystals of WHM materials. Experimental results of these topological states have been obstructed due to the difficulty to perform controlled in situ strain. This project strives to create a mount to utilize a piezoelectric nanopositioner within cryostats achieving an in situ strain that creates the quantum states the lab is looking to observe. This report also examines the necessary equations to determine ...


Design And Control Of A Peristaltic Pump To Simulate Left Atrial Pressure In A Conductive Silicone Model, Jeremy Collins 2021 University of Arkansas, Fayetteville

Design And Control Of A Peristaltic Pump To Simulate Left Atrial Pressure In A Conductive Silicone Model, Jeremy Collins

Mechanical Engineering Undergraduate Honors Theses

According to the CDC, atrial fibrillation is responsible for more than 454,000 hospitalizations and approximately 158,000 deaths per year. A common treatment for atrial fibrillation is catheter ablation, a process in which a long flexible tube is guided through the femoral artery and to the source of arrhythmia in the heart, where it measures the electrical potential at various locations and converts problematic heart tissue to scar tissue via ablation. This paper details the design and control of a low-cost ($400) peristaltic pump system using repetitive control to replicate blood pressure in the left atrium in a conductive ...


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