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Theses/Dissertations

2020

Engineering

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Full-Text Articles in Engineering

Cellular Attachment On Poly(Lactic Acid) For Use In Tissue Engineering, Stephen R. Hunter Dec 2020

Cellular Attachment On Poly(Lactic Acid) For Use In Tissue Engineering, Stephen R. Hunter

Masters Theses

Tissue engineering is a promising new method for organ regeneration. This method can be used to repair damaged tissue, or possibly replace a fully functional organ. In summary, a biopsy is taken from a donor, isolated, then grown onto a framework resembling an organ. Once grown; it is then transplanted into the patient. Over time, the body will degrade the scaffold, leaving the organ or tissue in its place. As this scaffold is present in the body for an extended time; factors like biocompatibility, toxicity, immunogenicity, and structural stability must be researched.

Several polymers have already been researched for use …


Protease Resistant Growth Factor Formulations For The Healing Of Chronic Wounds, Tabitha Boeringer Oct 2020

Protease Resistant Growth Factor Formulations For The Healing Of Chronic Wounds, Tabitha Boeringer

USF Tampa Graduate Theses and Dissertations

Chronic wounds are those wounds which are refractory to treatment, often taking years to heal. These wounds are complex and may present with elevated protease levels, resulting in rapid degradation of growth factors, both native and augmented via treatment. This study’s focus was the development of a system to protect growth factors from protease mediated degradation.

The protective system consisted of chimeric fusion proteins developed to contain both a growth factor or known protease inhibitory peptide and an Elastin-Like-Peptide (ELP)component. The unique phase transitioning abilities of the ELP component allowed for the self-assembly of these chimeric fusion proteins into a …


Observing The Impact Of An Engineering-Based Unit Of Instruction On 6th Grade Students' Attitudes Towards Engineering As Theyengage In Building Electric Bikes, Gregg Allred Olsen Jun 2020

Observing The Impact Of An Engineering-Based Unit Of Instruction On 6th Grade Students' Attitudes Towards Engineering As Theyengage In Building Electric Bikes, Gregg Allred Olsen

Theses and Dissertations

In the past few decades, science, technology, engineering, and math (STEM) education has become a driving force for innovators throughout the world (Atkinson & Mayo, 2010; Bybee, 2010). STEM education has also become an economic factor in developing countries (Kennedy & Odell, 2014). Currently, many countries are struggling with how to effectively promote STEM education. The United States (U.S.) provides an interesting case study. Despite being one of the global economic leaders, it is behind in STEM education compared to other nations (Atkinson & Mayo, 2010; Dugger, 2010). STEM education helps to build world leaders including marketable and knowledgeable employees …


Electromagnetic Actuator For Camless Engines, Nicholas Olesh, Charlie Thomas Glenwright, Tim Wills De Tone, Darya Daniel Darvish Jun 2020

Electromagnetic Actuator For Camless Engines, Nicholas Olesh, Charlie Thomas Glenwright, Tim Wills De Tone, Darya Daniel Darvish

Mechanical Engineering

This document summarizes the research, objectives, project plan, and design for developing an electromagnetic actuator valve for use in a camless internal combustion engine. While electromagnetic valve actuators have not been implemented into a working product to date, there have been many attempts to research and develop working prototypes. Similar products have been developed, but they do not use purely electromagnetic actuation. This research is significant because it shows the challenge that must be overcome and outlines potential design solutions to the problem. The objectives section highlights the problem statement and what is aimed to be achieved in this project. …


An Improved Method For Hospital Acquired Pressure Ulcer (Hapu) Prevention, Megan Morrissey, Jillian Yeager, Julia Beekman Jun 2020

An Improved Method For Hospital Acquired Pressure Ulcer (Hapu) Prevention, Megan Morrissey, Jillian Yeager, Julia Beekman

Honors Theses

Hospital acquired pressure ulcers (HAPUs), also called bedsores, are damage to the skin and/or underlying tissue caused by prolonged pressure on the bony areas of the body, with around 20% of pressure ulcers occurring in the heel region. Currently, the most common practice for HAPU prevention is arbitrary manual repositioning of patients by nurses every 1-2 hours. The goal of our project was to address HAPUs in the heel region of low mobility patients through an ulceration risk sensing system. Our team has created a wearable ulceration risk assessment system that combines individual patient risk data with real time pressure …


Heavenly Bodies Rsvp, Justin Tyler Spitzer, Allison Jean Turnbaugh, Jack William Boulware, Braden Alex Lockwood Jun 2020

Heavenly Bodies Rsvp, Justin Tyler Spitzer, Allison Jean Turnbaugh, Jack William Boulware, Braden Alex Lockwood

Mechanical Engineering

The purpose of the Heavenly Bodies RSVP project was to design and fabricate planet props, as well as a mechanism by which they could be raised and lowered in California Polytechnic State University’s Pavilion theater. The project team was comprised of four fourth year mechanical engineering students: Allison Turnbaugh, Braden Lockwood, Jack Boulware, and Justin Spitzer. We conducted extensive research to determine the ideal solution for the design problem brought to us by our sponsor. In our analysis, we discovered that the most important aspects of our design were the absolute reliability of the system, fire retardant material selection, and …


Product Realization Capstone: Element Proof Safety Steps For Willie Price Lab School, Catherine Thomas, Allan Heuerman, Jared Mumme May 2020

Product Realization Capstone: Element Proof Safety Steps For Willie Price Lab School, Catherine Thomas, Allan Heuerman, Jared Mumme

Honors Theses

The purpose of this document is to describe the process we took to complete our capstone which paired the Center for Manufacturing Excellence with the Willie Price Lab School. The goal of the capstone was to remake step stools for the students of Willie Price, as the last stools failed to withstand weather damage. However, with the COVID-19 pandemic, plans were hindered, shifting the goal from actually producing the steps to creating instructions so that a younger Center for Manufacturing class could complete the production at a later date. Standardized Work Instructions, a detailed production plan, and engineering drawings were …


Understanding Latina Undergraduate Engineering Student Persistence, Yarissa I. Ortiz-Vidal May 2020

Understanding Latina Undergraduate Engineering Student Persistence, Yarissa I. Ortiz-Vidal

Electronic Theses and Dissertations

In summary, this study focused on understanding the persistence of 20 Latina undergraduate engineering students enrolled at two public four-year Hispanic Serving Institutions. Key findings in this study showed that in order to contribute to their own persistence in engineering majors these Latina students activated their community cultural wealth: (a) not only to resist different forms of oppression, but also to thrive and excel in academic settings, (b) to take control of difficult and challenging experiences, (c) to take/receive knowledge from others, but also to give/share their knowledge (cyclical tendencies of CCW), (d) as well as revealing that helping others …


Beaver Creek Restorative Design Using Engineering In Nature, Lindsay M. Levatino May 2020

Beaver Creek Restorative Design Using Engineering In Nature, Lindsay M. Levatino

Senior Honors Projects, 2020-current

Stream restoration work can be instrumental for the wellbeing of an ecosystem. Located in the Shenandoah Valley in Virginia is Beaver Creek, a well-known spot for fly-fishing due to its pristine water conditions and open surroundings. In order to maintain these conditions, a 100-foot stretch of Beaver Creek needed to be restored to prevent further erosion, stabilize the banks, and enhance the natural habitats. The project involved excavating a sediment island, filling in an eroded bank, building a cross vane, and adding stakes. Local stakeholders came together to complete this project contributing their expertise, equipment, and time. The construction was …


Passive And Active Battery Balancing Methods Implemented On Second Use Lithium-Ion Batteries, Walter Bartek May 2020

Passive And Active Battery Balancing Methods Implemented On Second Use Lithium-Ion Batteries, Walter Bartek

Masters Theses

As the number of electric vehicles (EVs) increases, the number of used battery packs that require disposal increases; however, many of these packs still have useful capacity and can be repurposed. When using repurposed large lithium-ion battery packs, deviations between cells within a pack become problematic. These deviations result in a pack that is unbalanced, affecting performance and proving potentially hazardous when charging. Consequently, a battery management system (BMS) is needed. To provide safety, the BMS in this paper monitors and controls the operation of the battery pack. In addition, it controls the redistribution of charge between the cells within …


Irrigation Design In Montana: Accommodating Varying Water Accessibility Across The Continental Divide., John Garrett Lampson May 2020

Irrigation Design In Montana: Accommodating Varying Water Accessibility Across The Continental Divide., John Garrett Lampson

Biological and Agricultural Engineering Undergraduate Honors Theses

The design work performed in this project was conducted over two summers (2018, 2019) of internship experience with the Natural Resources Conservation Service (NRCS) across the state of Montana. The first summer’s design work was based out of Glendive, MT, in Dawson County, approximately 50 kilometers from the North Dakota border. The second summer was in Missoula, MT, in Missoula County, near the Idaho border. The two areas differ significantly in topography, weather, and water availability with the main separating geographic influence being the Rocky Mountains.

This paper focuses on the design process and requirements for two farms located outside …


Academic Honesty, Professional Integrity, And Undergraduate Engineering Students: Exploring The Connections, S. Amy Skyles, Jeffrey W. Jennings Apr 2020

Academic Honesty, Professional Integrity, And Undergraduate Engineering Students: Exploring The Connections, S. Amy Skyles, Jeffrey W. Jennings

Dissertations

One benefit of inculcating professionalism into engineering degree program curricula is a measure of the extent to which future practitioners adopt an engineering code of ethics (Abaté, 2011; Davis, 2006). Studies have indicated more dishonesty among engineering students than other groups of undergraduate learners, but the effects of technology on dishonesty in the classroom was not addressed (Bowers, 1964; McCabe et al., 2012). An explanatory, sequential mixed methods study was designed to explain to what degree course pedagogical practices and attitudes of civil, architectural and environmental engineering students of various academic levels (freshman/sophomore and senior) relate to academic dishonesty. The …


Liability Of The Structural Engineer: Establishing, Quantifying, And Managing Risks, Justin Thomas Ittmann Jan 2020

Liability Of The Structural Engineer: Establishing, Quantifying, And Managing Risks, Justin Thomas Ittmann

LSU Doctoral Dissertations

Liability is an important topic to all practicing professionals—including practicing engineers. However, the topic of liability does not receive the necessary attention required relative to other professions. Further, engineers that desire to learn more about liability in relation to their practice do not have many university options within an engineering curriculum or from outside materials available to a non-legally trained engineer. The goal of the study is to provide a comprehensive overview of liability directed towards an intelligent practicing engineer, while avoiding unnecessary over-simplification of the material. This study initially provides an in depth survey of the legal standard of …


Jcati Composite Delaminator, Payden Coffman Jan 2020

Jcati Composite Delaminator, Payden Coffman

All Undergraduate Projects

Improvements need to be made to the existing delaminator system designed to crush proprietary Boeing 777 composite material. The current design incorporates a hydraulic system to achieve the high loads needed to separate material layers. The new system will need to be able to apply the same loads while at the same time allowing for a constant feed of material through the system. To achieve this, a “gear-like” crushing system will be implemented that will apply a high enough radial load into the material that will achieve delamination equal or greater than the previous design while at the same time …


A Narrative Approach To Understanding Career Attrition For Women Engineers, Brian Merritt Scott Jan 2020

A Narrative Approach To Understanding Career Attrition For Women Engineers, Brian Merritt Scott

Walden Dissertations and Doctoral Studies

More women exit the engineering profession than enter, leaving a talent void that incurs lost business value from unrealized business revenues. Without new insights about how to address the continued attrition of women engineers, the profession is unlikely to sustain the human capital needed to achieve competitive advantages through innovation, increased productivity, and improved firm reputation. This qualitative narrative inquiry explored the career attrition phenomenon of six former women engineers in the Northern Tier States region of the United States who left engineering within the past 4 years and were either an engineer-in-training or professional engineer. The conceptual framework for …


A Narrative Approach To Understanding Career Attrition For Women Engineers, Brian Merritt Scott Jan 2020

A Narrative Approach To Understanding Career Attrition For Women Engineers, Brian Merritt Scott

Walden Dissertations and Doctoral Studies

More women exit the engineering profession than enter, leaving a talent void that incurs lost business value from unrealized business revenues. Without new insights about how to address the continued attrition of women engineers, the profession is unlikely to sustain the human capital needed to achieve competitive advantages through innovation, increased productivity, and improved firm reputation. This qualitative narrative inquiry explored the career attrition phenomenon of six former women engineers in the Northern Tier States region of the United States who left engineering within the past 4 years and were either an engineer-in-training or professional engineer. The conceptual framework for …


Design And Implementation Of Simplified Sliding-Mode Control Of Pwm Dc-Dc Converters For Ccm, Humam A. Al-Baidhani Jan 2020

Design And Implementation Of Simplified Sliding-Mode Control Of Pwm Dc-Dc Converters For Ccm, Humam A. Al-Baidhani

Browse all Theses and Dissertations

The pulse-width modulated (PWM) dc-dc converters play a vital role in several industrial applications that include motor drives, electric vehicles, dc distribution systems, and consumer electronics. The switched-mode power converters step the input voltage up or down based on their typology and provide a regulated output voltage. The stability and regulation performance of a power converter can tremendously be improved via a suitable control design. However, due to the nonlinearity of the power converters and the presence of the line and load disturbances, the design of a robust and low-cost control circuit becomes a challenging task. The sliding-mode control of …


Eye-Tracking To Evaluate Trust In Human-Atr Interaction, Samuel Francis Adelman Jan 2020

Eye-Tracking To Evaluate Trust In Human-Atr Interaction, Samuel Francis Adelman

Browse all Theses and Dissertations

Human collaboration with targeting aids have allowed analysts to achieve a greater level of coordination and productivity in a variety of fields. This project investigates the impact that an Assisted Target Recognition (ATR) algorithm’s false alarm rate and the task Target of Interest (TOI) level has on user-system trust and use in a targeting decision task. Previous studies suggest that an increased number of false alarms in an ATR task negatively impacts analyst trust in the system. This study will further contribute to this research, aiming to provide a better framework for appropriate tolerance levels within ATR algorithms, utilizing pre-truthed …


Hierarchical Structure, Properties And Bone Mechanics At Macro, Micro, And Nano Levels, Farah Mohammed Ridha Abdulateef Hamandi Jan 2020

Hierarchical Structure, Properties And Bone Mechanics At Macro, Micro, And Nano Levels, Farah Mohammed Ridha Abdulateef Hamandi

Browse all Theses and Dissertations

This research focuses on the hierarchical structure of bone and associated mechanical properties at different scales to assess damage accumulation leading to premature failure, with or without instrumentation. In this work, an attempt was made to develop a framework of macro, micro, and nano damage accumulation models and implementing them to derive mechanical behavior of the bone. At macrolevel, retrospective evaluation of 313 subjects was conducted, and the damage of bone tissue was investigated with respect to subject demography including age, gender, race, body mass index (BMI), height and weight, and their role in initiating fracture. Experimental data utilized 28 …


Optimization Study Of A Combined Wind-Solar Farm For A Specified Demand, Venkat Siddhartha Rama Jan 2020

Optimization Study Of A Combined Wind-Solar Farm For A Specified Demand, Venkat Siddhartha Rama

Browse all Theses and Dissertations

At the present time, using wind and solar energy for producing electricity in the United States is becoming cost competitive. According to Lazard’s 2019 [36] levelized cost of energy (LCOE) analysis of a number of energy sources used for producing electricity in the United States, wind and solar are cheaper than natural gas and coal. While capital, maintenance, operation, and fuel costs are included in LCOE numbers, energy source intermittency is not. Intermittency is an important issue with wind and solar energy sources, but not with natural gas or coal energy sources. Combining wind and solar energy sources into one …


Joint Shelf Design And Shelf Space Allocation Problem For Retailers, Hakan Gecili Jan 2020

Joint Shelf Design And Shelf Space Allocation Problem For Retailers, Hakan Gecili

Browse all Theses and Dissertations

Although the retail business has been exploring innovative ways to engage shoppers, the COVID-19 pandemic has sped up their effort. Because of its unique benefits, physical stores will continue to remain an integral part of the overall retail business. However, to stay competitive, retailers will be forced to effectively utilize their available space in physical store (and even reduce it if need be), while offering a reasonably large assortment of products on their shelves. For many such retailers, the design of planograms – visual representation of products on shelves – is still driven by prior experience and intuition. Further, existing …


Adaptive Multi-Fidelity Modeling For Efficient Design Exploration Under Uncertainty, Atticus J. Beachy Jan 2020

Adaptive Multi-Fidelity Modeling For Efficient Design Exploration Under Uncertainty, Atticus J. Beachy

Browse all Theses and Dissertations

This thesis work introduces a novel multi-fidelity modeling framework, which is designed to address the practical challenges encountered in Aerospace vehicle design when 1) multiple low-fidelity models exist, 2) each low-fidelity model may only be correlated with the high-fidelity model in part of the design domain, and 3) models may contain noise or uncertainty. The proposed approach approximates a high-fidelity model by consolidating multiple low-fidelity models using the localized Galerkin formulation. Also, two adaptive sampling methods are developed to efficiently construct an accurate model. The first acquisition formulation, expected effectiveness, searches for the global optimum and is useful for modeling …


Quadrotor Uav Flight Control With Integrated Mapping And Path Planning Capabilities, Jason A. Gauthier Jan 2020

Quadrotor Uav Flight Control With Integrated Mapping And Path Planning Capabilities, Jason A. Gauthier

Browse all Theses and Dissertations

Quadrotor UAVs have become a common and easily acquirable hardware platform for research and development with control laws, mapping systems, and path planning. In this research, a non-linear model of a quadrotor UAV is linearized with model parameters being identified using collected flight data. The PID, LQR, and backstepping control laws are implemented. An adaptive control law is also implemented to handle the loss of effectiveness in motor actuation. Additionally, this research also implements a laser-based SLAM algorithm for mapping and localization in an unknown two-dimensional environment. Path planning and obstacle avoidance algorithms are implemented onboard using the Robot Operating …


Stabilization Of Β-Cristobalite In The Sio2-Alpo4-Bpo4 System, Kathryn Doyle Jan 2020

Stabilization Of Β-Cristobalite In The Sio2-Alpo4-Bpo4 System, Kathryn Doyle

Browse all Theses and Dissertations

Fused silica (silica glass) is transparent in the optical and near-infrared and has a low dielectric constant, making it suitable as a window material for radio frequency radiation. However, at high temperatures (>1100C), fused silica will easily creep and lose dimensional stability. Crystallized silica is much more creep resistant than fused silica. Silica crystallizes to many different structures including quartz, tridymite, and α- and β cristobalite. The only cubic polymorph, which is suitable for both optical and radio frequency transmission in polycrystalline form, is β -cristobalite. Unfortunately, this polymorph transforms to α-cristobalite at ~300C, and the volume change during …


A First Principles Study Of Pipe Diffusion In Nickel, Luke J. Wirth Jan 2020

A First Principles Study Of Pipe Diffusion In Nickel, Luke J. Wirth

Browse all Theses and Dissertations

Vacancy-mediated diffusion along dislocations, often referred to as pipe diffusion, can contribute to creep deformation of metals in many engineering applications. This process is studied along an a/2⟨1 -1 0⟩ screw dislocation in fcc Ni using a density functional theory approach. An accurate geometrical configuration of the screw dislocation core, dissociated into Shockley partial dislocations and separated by a stacking fault, was previously derived using a lattice Green's function technique. Activation energies and frequencies are calculated for atom-vacancy exchanges that contribute to diffusion around and along one of the partial cores. This analysis reveals the significant role of the sites …


Understanding Visual Representation Of Imputed Data For Aiding Human Decision-Making, Ryan M. Thompson Jan 2020

Understanding Visual Representation Of Imputed Data For Aiding Human Decision-Making, Ryan M. Thompson

Browse all Theses and Dissertations

The effectiveness of representing higher dimensional data on a two-dimensional visualization was required to be studied in the development of a novel data imputation method, Continuous Imputation With Association Rules (CIWAR). When the CIWAR method is used to impute missing data, the method generates additional metadata that increases each imputed data point's dimensionality. Potential use cases for CIWAR include situations where imputed data would be analyzed by individuals with little or no data analytic experience or situations where imputed data would be used to aid high-stress time-critical human decision processes. A study was conducted to assess the effect of the …


Hierarchical Hybrid Materials From Flexible Fabric Substrates, Wenhu Wang Jan 2020

Hierarchical Hybrid Materials From Flexible Fabric Substrates, Wenhu Wang

Browse all Theses and Dissertations

The goal of this project is to investigate fabrication approaches and structure-property relationships of porous and flexible hierarchical hybrid solids suitable for advanced surface-active devices. Multi-scale hierarchical carbon materials are being fabricated by strong covalent attachment of multiwall carbon nanotube(MWCNTs) arrays on flexible carbon fabric substrates in order to enhance the surface area per unit volume. This was done using chemical vapor deposition (CVD) after functionalizing the surface with a plasma-derived nano-oxide coating. Structural and chemical characterization is performed using scanning electron microscope(SEM), energy dispersive spectroscopy(EDS) and x-ray photoelectron spectroscopy(XPS). Surface area estimates have been made by building structural models …


Processing And Properties Of Multifunctional Two Dimensional Nanocomposites Based On Graphene Nano-Flakes, Mohammed K. Mohammed Jan 2020

Processing And Properties Of Multifunctional Two Dimensional Nanocomposites Based On Graphene Nano-Flakes, Mohammed K. Mohammed

Browse all Theses and Dissertations

The unique properties of graphene have directed researchers to study and characterize this new material. Graphene production and graphene based materials have been widely explored and developed in the past decade. Most research has aimed at developing scalable, environmentally friendly, and cheap procedures to produce defect-free graphene that can be used in various applications such as mechanical properties enhancement and multifunctional material. The challenge is processing such material on a scale suitable for engineering applications such as advanced photonics and advanced electronics. In this study, we investigate a new processing technique based on Langmuir-Blodgett (LB) Technique. We managed to produce …


Ideal Lacrosse Stick, Josh Beck, Tyler Skoloda, Noah Reed, Stanley Dembosky Jan 2020

Ideal Lacrosse Stick, Josh Beck, Tyler Skoloda, Noah Reed, Stanley Dembosky

Williams Honors College, Honors Research Projects

This project is focused on the design of a new and innovative lacrosse stick. Our main points of focus will be the strength and durability of the head. As well as solving some of the problems that exist in existing equipment. These problems were identified by interviewing experienced players at the college level. Benefits would include a stronger head that is easier to use for a player on the field to do things like pass, catch, shoot, and field ground balls in an optimal manner. Normally players will have to purchase new heads every season as a result of warping …


Bioimpedance Sensor, Ryan Byo, Kevin Libertowski Jan 2020

Bioimpedance Sensor, Ryan Byo, Kevin Libertowski

Williams Honors College, Honors Research Projects

A bioimpdance senor to measure the impedance of a human body. Completed as part of the engineering Senior Design Project