Engineering Commons^™

Structural Retrofit Of Reinforced Concrete Circular Columns Using Cfrp, Ahmed Haider Mohiuddin

Civil Engineering Theses - Archive

Fiber reinforced polymer (FRP) composites have developed numerous applications in the field of Civil Engineering, mostly because of their beneficial properties like high strength-to=weight ratio and high corrosion resistance. This study presents an easy and expedient finite element (FE) able to accurately estimate the axial load carrying capacity of reinforced concrete (RC) circular columns confined with externally bonded carbon fiber reinforced polymer (CFRP) sheets. The element is able to model collapse due to concrete crushing. The FE generated in this study is used the load carrying capacity of CFRP confined RC columns subjected to concentric loading. Constitutive models for materials …

Discriminating Parkinson's Disease Using Functional Connectivity And Brain Network Analysis, Daniel Gellerup

Industrial, Manufacturing, and Systems Theses - Archive

In this study, we explored the use of functional connectivity patterns in fMRI data to classify subjects on the basis of Parkinson's disease. We explore various brain networks and features. We partition our fMRI data in 5 filtered frequency ranges. We use a proximal support vector machine paired with a minimum-redundancy and maximum-relevance feature selection method on each frequency range. We use a majority voting ensemble classification method on the results of the proximal support vector machine classification results. We use a double 5-fold cross validation scheme for model validation. We achieve 84% accuracy 74% sensitivity, and 93% specificity. Our …

Pedicle Lengthening Spacer, David S. Wood

Undergraduate Honors Capstone Projects

In the lumbar region of the spine, the spinal cord travels through a small hole in your vertebrae called the spinal canal. There is a medical condition where the spinal canal becomes restricted. This condition is called stenosis. There are several reasons for this pinching of the spinal column. These include the growth of bone spurs, the accumulation of ligaments in the canal, or a genetic trait. When these occur in the lower five vertebrae (the lumbar region), it is called lumbar stenosis. The symptoms of Lumbar Stenosis are shooting pain through the legs, especially during activity, and feelings of …

Xhab Microgravity Food Growth Chamber, Nathan I. Stacey

Undergraduate Honors Capstone Projects

NASA and other organizations are preparing to send humans deeper into space, including a NASA manned mission to Mars in the 2030s, in order to learn more about our universe and the origin of life and to ensure the survival of the human race. Long journeys in space require efficient, dependable, and sustainable methods to provide for astronauts' metabolic needs such as oxygen, water, and food. In order for microgravity plant growth chambers to become a viable solution, several challenges encountered by past growth chambers must be resolved.

One problem with existing space food growth chambers is hypoxia, or lack …

Investigating The Effect Of Capping Layers On Final Thin Film Morphology After A Dewetting Process, Benjamin C. White

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Nanoparticles on a substrate have numerous applications in nanotechnology, from enhancements to solar cell efficiency to improvements in carbon nanotube growth. Producing nanoparticles in a cheap fashion with some control over size and spacing is difficult to do, but desired. This work presents a novel method for altering the size and spacing of nickel and gold nanoparticles. Dewetting is a methodology to reduce thin films to an ensemble of discrete droplets. The introduction of alumina capping layers to thin nickel films during a pulsed laser-induced dewetting process has yielded reductions in the mean and standard deviation of radii and pitch …

Analysis And Modeling Of Pedestrian Walking Behaviors Involving Individuals With Disabilities, Mohammad Sadra Sharifi

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Walking facilities like walkways and stairs are important infrastructures which must be designed to effectively accommodate the behavior of pedestrians. Heterogeneity in pedestrian composition is one important factor generally overlooked in walking facility design guidelines and handbooks. While individuals with disabilities constitute a significant portion of the population in the United States, they are often overlooked due to lack of available data. To remedy this, large scale controlled walking experiments were performed at Utah State University (USU) to study the walking behavior of various types of individuals with disabilities (including vision and mobility impairments) in different walking environments. These environments …

Investigating Biosynthetic Steps Of An Angucycline Antifungal, S. Gabrielle Gladstone

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The species of bacterium Streptomyces sp. SCC-2136 which has the American Type Culture Collection index 55186 naturally produces two chemical compounds, labeled Sch 47554 and Sch 47555. These compounds were previously reported to posess antifungal activity. This thesis sets out to confirm the mechanism by which the bacterium produces these compounds; specifically which genes are responsible for producing the enzymes that make and shape the molecules.

The genes and enzymes that were characterized are the minimal polyketide synthase, the ketoreductase that specifically acts on the ninth carbon, the first-ring aromatase, the subsequent ring cyclase, and two oxygenases. Also elucidated …

Understanding The Characteristics Of Successful Projects And Post-Campaign Activities In A Crowdfunding Platform, Madhavi Reddy Dontham

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Online crowdfunding platforms provide project creators with new opportunities for seeking funds from people in the world. But reaching a fund-raising goal or making a project successful is always a challenge. Besides, little is known about post-campaign activities of project creators and backers. To fill the gap, in this research, we are interested in understanding (i) the characteristics of successful projects, (ii) how project creators reacted when their projects failed, and (iii) what post-campaign activities creators and backers made. To achieve our research objectives, first, we analyzed successful projects and failed projects on Kickstarter, the most popular crowdfunding platform. Then …

Partially Closed Valve Effects On Electromagnetic Flow Meter Accuracy, Jordan Clark Jarrett

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

As the need to manage water resources increases, the ability to accurately measure use becomes crucial. In industry, measurement inaccuracies can cost either the
supplier or consumer large amounts of money or even result in a depleted resource. Generally, flow meters need a flow profile to be fully developed so to optimize
measurement accuracy.

In order to produce accurate measurements, most flow meters require a straight section of pipe immediately upstream of the meter. The straight pipe helps to develop the flow profile and produces flow conditions that are as ideal as possible. In many field installations, space restrictions lead …

Global Thermospheric Response To Geomagnetic Storms, Padmashri Suresh

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The terrestrial atmospheric region between the altitudes of 90 km and 600 km is known as the thermosphere region. The thermosphere is continuously modulated by particle emissions and magnetic fields that originate from the sun. These fields and emissions are intensified during events known as geomagnetic storms which alter the state of the thermosphere by dumping gigawatts of energy. This energy is mostly deposited in the lower thermosphere regions of 150 km and below and can potentially have hazardous repercussions on the technological assets of mankind. These storms can disrupt radio communication systems, interrupt electric power systems, threaten the safety …

Plasma Velocity Vector Instrument For Small Satellites (Pvviss), William Smith Hatch

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Low-earth orbit (LEO) contains plasma which can impact satellite charging and radio frequency (RF) communications. Quantifying both the composition and movement of ions in LEO can improve efficiency of the forecasting models that predict the impact plasma will have on satellite communications and accuracy of global positioning satellite measurements.

Two instruments known as the Retarding Potential Analyzer (RPA) and the Ion Drift Meter (IDM) have been used in tandem to measure ionospheric properties including ion temperature, velocity, and density. These instruments are costly and occupy large areas on a spacecraft. In recent years, space mission budgets have diminished. This change …

An Analysis Of Airborne Data Collection Methods For Updating Highway Feature Inventory, Yi He

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Highway inventory plays an important role in highway management. Governments and agencies have been employing different kinds of methodologies for highway inventory. Existing methodologies include field inventory, photo/video log, integrated global positioning system (GPS)/ global information system (GIS) mapping, aerial/satellite photography, terrestrial light detection and ranging (LiDAR), mobile LiDAR, and airborne LiDAR. Each has advantages and disadvantages as well as limitations in collecting road inventory data. This paper mainly focused on the application of airborne data collection method.

Four highway sections in Utah were mapped in this experiment: one section on Interstate 84 (I-84), two sections on Interstate 15 (I-15 …

Quantifying The Removal Of Trichloroethylene Via Phytoremediation At Hill Air Force Base, Utah Operational Unit 2 Using Recent And Historical Data, J. Oliver Diamond

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Trichloroethylene (TCE) is a carcinogenic, chlorinated volatile organic compound that was commonly used as a degreasing solvent for aircraft maintenance at many US Air Force bases. Past improper disposal of TCE has resulted in contaminated groundwater plumes surrounding many of these facilities. Phytoremediation, defined as the use of plants and their associated microorganisms to stabilize or remove contamination, has been implemented as part of a TCE groundwater cleanup effort at Travis Air Force base near Sacramento, CA and is being considered as a remediation option at other bases. Volatilization of TCE from leaves and the surface of the soil near …

Developing A Method For Quantifying Nitrogen Transformation Rates Using In Situ Benthic Chambers Dosed With Isotopically Labeled Nitrate, Chelsea A. Stewardson

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Nitrogen, a nutrient required for biological growth, is a common water quality parameter of concern as too much nitrogen can cause a strain on aquatic environments and even death of plants and animals. One way high levels of nitrogen are introduced into aquatic systems is by anthropogenic sources such as effluent from water reclamation facilities. A method was designed to observe the fate of nitrogen and measure the rates of its transformation into different nitrogen species within a stream receiving the effluent from the Silver Creek Water Reclamation Facility in Park City, Utah.

Sealed chambers were designed and installed along …

Developing More Efficient Mechanically Stabilized Earth (Mse) Wall Reinforcements, Matthew J. Rahmeyer

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The most common shape for metallic reinforcement in Mechanically Stabilized Earth (MSE) walls is a rectangular strip. The amount of force required to pull the reinforcement out of the wall versus how much steel is required is well balanced.

This study shows that a metal round bar can be altered, either by bending into various geometries or welding into crossbars, and provide similar and sometimes higher resistance to pullout than the rectangular strip. This was achieved while reducing the weight per foot of reinforcement of steel required and providing cost saving benefits.

Development Of A Novel Device For Ventricular Assist Device Outflow Graft Anastomosis., Young Choi

Electronic Theses and Dissertations

Purpose: Left ventricular assist device (LVAD) therapy can be live-saving for advanced heart failure patients. Conventional anastomosis (surgical connection) of LVAD outflow grafts to the aorta requires aortic clamping and hand-suturing. Aortic clamping increases the risk for neurological complications. Hand-suturing may be time-consuming and requires significant surgical dexterity. There is currently no commercially available device for sutureless anastomosis of large vascular grafts (diameter > 5mm). To overcome these limitations, a prototype LVAD outflow graft anastomosis device (GrAD) that facilitates sutureless anastomosis was developed and tested to demonstrate proof-of-concept and feasibility for (1) secured attachment withstanding physiological pressures, and (2) comparable attachment …

The Effects Of Ball Interactions On The Dynamic Behavior Of A Ball Balancer Rotating At Speeds Above The Translational Resonant Frequency Of The System., Gregory A. Dedow

Electronic Theses and Dissertations

Many applications are inherently rotational in nature. These applications range from industrial products to consumer products. As seen in a traditional frequency response plot, the motion of a rotating imbalance does not approach zero as the forcing frequency is increased. Unlike a traditional forced mass spring oscillator, the motion of the rotating imbalance approaches some non-zero value. To account for this residual motion, some systems utilize a balancing device to reduce this motion. These balancing devices can be passive or active, depending on the design considerations. This paper will focus on the traditional, passive ball-type balancer due to its simplicity …

Evaluating The Economic Impacts Of The Legislatively Delayed Provisions Of The 5th Edition (2014) Florida Building Code (Final Report), Florida Solar Energy Center, Robin Vieira

FSEC Energy Research Center®

This research provides an assessment of the potential economic impacts of implementing three legislatively delayed requirements of the Florida Building Code, 5th Edition (2014): 1) residential air leakage testing, 2) residential whole-house mechanical ventilation, and 3) two fire service access elevators for applicable buildings.

Engineering Of Polyketide Biosynthetic Pathways For Bioactive Molecules, Siyuan Wang

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

This study is focused on engineering of natural product biosynthetic pathways for efficient production of pharmaceutically important molecules or generation of new bioactive molecules for drug development.

Plant natural products are an important source of therapeutics, such as paclitaxel (anticancer) and artemisinin (anti-malarial). Production of plant natural products relies on conventional plant cultivation and solvent extraction, which is time-consuming and cost-ineffective. This work built a biosynthetic platform in Escherichia coli using seven biosynthetic genes from plants and bacteria, which were used to make valuable compounds such as the strong antioxidant resveratrol and anti-inflammatory agent curcuminoids. Through different combinations of these …

Impact Of Heavy Metal Contamination From Coal Flue Gas On Microalgae Biofuel And Biogas Production Through Multiple Conversion Pathways, Derek E. Hess

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Microalgae has a great potential to help alleviate the world's current dependence on fossil fuels. Microalgae is a single celled organism that produces lipids as a food storage device much like humans and animals store fat. These lipids are a kind of oil that when harvested can be utilized as biofuel.

As the technology surrounding using microalgae as a source of biofuel has advanced key bottlenecks in the eventual large-scale production of microalgae based biofuel have been discovered. One of these bottlenecks is the need to cheaply supply carbon for microalgae growth. One idea that has emerged as a plausible …

Nonparametric Anomaly Detection And Secure Communication, Shaofeng Zou

Dissertations - ALL

Two major security challenges in information systems are detection of anomalous data patterns that reflect malicious intrusions into data storage systems and protection of data from malicious eavesdropping during data transmissions. The first problem typically involves design of statistical tests to identify data variations, and the second problem generally involves design of communication schemes to transmit data securely in the presence of malicious eavesdroppers. The main theme of this thesis is to exploit information theoretic and statistical tools to address the above two security issues in order to provide information theoretically provable security, i.e., anomaly detection with vanishing probability of …

Interactions Between Inflammatory Cells And Cocrmo Alloy Surfaces Under Simulated Inflammatory Conditions, Huiyu Shi

Dissertations - ALL

Metallic biomaterials continue to be the primary materials for medical devices because of their excellent physical and mechanical properties especially for certain implants which need high strength (hip, spinal, shoulder, knee etc.). However there is no perfect material to meet all the requirements of a medical device. Metallic biomaterials are prone to corrosion and wear which has been associated with implant failure (osteolysis, aseptic loosening, pseudo tumor etc.) This study focused on investigating how inflammatory cells interact with CoCrMo alloy surfaces under simulated inflammatory conditions (H2O2 treatment). It is hypothesized that the presence of Reactive Oxygen Species (ROS) in cell …

Statistical Learning Tools With Food Science, Jessica C. Hacker

Industrial Engineering Undergraduate Honors Theses

The food science discipline has many issues requiring research within academia in order to protect the food that gets distributed from industry. The team within the Center for Food Safety at the University of Arkansas’ Division of Agriculture has been studying the gastrointestinal microbial community in broiler chickens in order to control pathogenic bacteria and improve gut health within the chickens to promote a healthy adult microbiota. This has many positive effects on the quality of the chickens. The team performs a standard method of analysis on every experiment run within a software called QIIME to determine if a treatment …

Developing A Risk Analysis Model To Improve Study Abroad Awareness, Tyler Spain

Industrial Engineering Undergraduate Honors Theses

As international education opportunities increase in popularity among U.S. college students (McMurtrie, 2007), it is becoming more and more necessary for study abroad organizations to be aware of the risks students face as they travel abroad. While some international cities are riskier than others, it can be difficult to distinguish between cities which truly carry a high degree of risk for visiting students, and which cities are only perceived to be risky based on various personal misconceptions. The University of Arkansas Office of Study Abroad & International Exchange currently lacks a way to quantifiably analyze the risk of study abroad …

Microspine Gripping Mechanism For Asteroid Capture, Ezekiel G. Merriam, Andrew B. Berg, Andrew Willig, Aaron Parness, Tim Frey, Larry L. Howell

Student Works

This paper details the development and early testing of a compliant suspension for a microspine gripper device for asteroid capture or micro-gravity percussive drilling. The microspine gripper architecture is reviewed, and a proposed microspine suspension design is presented and discussed. Prototyping methods are discussed, as well as testing methods and results. A path forward is identified from the results of the testing completed thus far. Key findings include: the microspine concept has been established as a valid architecture and the compliant suspension exhibits the desired stiffness characteristics for good gripping behavior. These developments will aid in developing the capability to …

Numerical And Analytical Modeling To Determine Performance Trade-Offs In Hydrogel-Based Ph Sensors, Piyush Dak, Muhammad Ashraful Alam

Birck and NCN Publications

Hydrogel based pH sensors are promising candidates for implantable sensors due to their low-cost and biocompatibility. Despite their commercial potential and numerous theoretical/experimental reports, the trade-offs between different performance parameters are not well understood, and explicitly stated. In this work, we develop a numerical and analytical framework to show that there is a fundamental trade-off between the performance parameters i.e. sensitivity/dynamic range vs. response-time/response-asymmetry in hydrogel sensors under constrained swelling conditions. Specifically, we consider the effect of the gel parameters, such as the ionizable group density ( N_f) and its dissociation constant ( K_a), on the …

Deontological Ethical System For Google's Self-Driving Car, Edgard Alejandro Arroliga Jr.

Computer Science and Software Engineering

Google's Self-Driving Car is a revolutionary product that is riddled with ethical conundrums. It is able to accurately scan and drive through densely populated roads without much difficulty. However, there are some situations where the car will likely have to make decisions that affect, maybe even take, the lives of those on the road. Issues such as the Trolley Problem and the Rear-End Dilemma describe situations where there seems to be no single ethical answer as to how the car should act. In order to solve these issues, I propose that a Deontological Ethical System should be implemented because it …

Isolation Of Metallic Single-Walled Carbon Nanotubes For Electrically Conductive Tissue Engineering Scaffolds, Jakob Hockman

Biomedical Engineering Undergraduate Honors Theses

Metallic single-walled carbon nanotubes (m-SWNTs) were separated from pristine SWNTs using affinity chromatography for use in electrically conductive tissue engineering scaffolds. Approximately one third of SWNTs have metallic properties. Separations were achieved using a protocol modified from Liu & coworkers (2011) in order to improve the method for cell culture environments. Samples enriched in m-SWNTs were isolated and characterized. However, challenges still remain for the complete separation of m-SWNTs from their semiconducting counterpart (s-SWNTs) using this protocol. Approaches to improve separation and reduce the difficulties associated with processing the nanotubes were suggested. One of the ultimate destinations of these nanotubes …

A System Dynamics Approach Applied To Wind Energy System Sustainability, Jenny Maria Tejeda Carlos

Industrial, Manufacturing, and Systems Engineering Dissertations - Archive

Sustainability of energy systems is one of the most important challenges currently facing humanity. Access to energy is critical to ensure economic and social development of a nation (UNDP et al., 2000); however, extraction, production and consumption of energy resources are also associated with high volumes of greenhouse gas (GHG) emissions, environmental damage and, in some cases, adverse health effects in communities where energy facilities are located. Renewable energy sources have been considered as an alternative to traditional energy sources to meet energy demand in a sustainable manner (Del Rio and Burguillo, 2008). Wind energy is considered to be one …

Dynamic Constraint Optimal Selection Techniques For Linear Programming, Alireza Noroziroshan

Industrial, Manufacturing, and Systems Engineering Dissertations - Archive

Linear programming has been studied for over 60 years. It has been considered as one of the most valuable optimization tool for many industrial problems. The simplex algorithm remains the predominant approach to solving linear programming problems. Here we use the simplex method in an active-set frame work to improve it substantially. In general an active-set method obtains solutions by adding one or more problem constraints at a time to solve smaller problems iteratively. In particular, some of these methods have proven to perform significantly faster than the simplex method. In this dissertation we proposed an e?cient constraint selection metric …