Engineering Commons^™

Automatic Testing In The United States Air Force, Pearson Wade

Computer Science and Computer Engineering Undergraduate Honors Theses

The need for standardized Automatic Testing Equipment in the United States Department of Defense has brought about new policies and procedures within entities like the United States Air Force. The diversity and lifespan of systems such as jets, missiles, drones, and other electronics have brought on the need for a new system known as the Versatile Depot Automatic Test Station, or VDATS. The VDATS handles the automatic testing of replaceable digital circuits from different systems. I was introduced to this system firsthand during my time as an intern at Tinker AFB, Oklahoma. This new standardized approach to testing a diverse …

Flexural Rigidity Evaluation Of Seismic Performance Of Hollow-Core Composite Bridge Columns, Mohanad M. Abdulazeez, Mohamed Elgawady

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

This paper investigates experimentally the seismic behavior of two hollow-core fiber-reinforced polymer-concrete-steel HC-FCS columns under cyclic loading as a cantilever. The typical precast HC-FCS member consists of a concrete wall sandwiched between an outer fiber-reinforced polymer (FRP) tube and an inner steel tube. The FRP tube provides continuous confinement for the concrete wall along the height of the column. Five large-scale HC-FCS columns were investigated during this study to estimate the effective flexural (which is an important factor to define the buckling capacity and deflection of such columns) and the effective structural stiffness of the composite columns. These columns have …

Scada And Plc Systems Configuration For The Ncrept Test Facility, Arman Ahmed

Electrical Engineering Undergraduate Honors Theses

This thesis details the project to update the control and interface system of the National Center for Reliable Electric Power Transmission (NCREPT) testing facility. The need for this project arose from the 2017-2018 expansion of the facility, which included some modifications in the layout of electrical equipment used for testing purposes. These modifications necessitated the update of the control and interface system. Additionally, the old system was implemented a decade ago and is nearing obsolescence, so the facility’s expansion served as an opportune time for an upgrade.

There were two main parts to the scope of this project, which were …

Dynamic 3d Network Data Visualization, Brok Stafford

Computer Science and Computer Engineering Undergraduate Honors Theses

Monitoring network traffic has always been an arduous and tedious task because of the complexity and sheer volume of network data that is being consistently generated. In addition, network growth and new technologies are rapidly increasing these levels of complexity and volume. An effective technique in understanding and managing a large dataset, such as network traffic, is data visualization. There are several tools that attempt to turn network traffic into visual stimuli. Many of these do so in 2D space and those that are 3D lack the ability to display network patterns effectively. Existing 3D network visualization tools lack user …

The 3d Abstract Tile Assembly Model Is Intrinsically Universal, Aaron Koch, Daniel Hader, Matthew J. Patitz

Computer Science and Computer Engineering Undergraduate Honors Theses

In this paper, we prove that the three-dimensional abstract Tile Assembly Model (3DaTAM) is intrinsically universal. This means that there is a universal tile set in the 3DaTAM which can be used to simulate any 3DaTAM system. This result adds to a body of work on the intrinsic universality of models of self-assembly, and is specifically motivated by a result in FOCS 2016 showing that any intrinsically universal tile set for the 2DaTAM requires nondeterminism (i.e. undirectedness) even when simulating directed systems. To prove our result we have not only designed, but also fully implemented what we believe to be …

Reprapable Recyclebot: Open Source 3-D Printable Extruder For Converting Plastic To 3-D Printing Filament, Aubrey Woern, Joseph Mccaslin, Adam Pringle, Joshua M. Pearce

Department of Materials Science and Engineering Publications

In order to assist researchers explore the full potential of distributed recycling of post-consumer polymer waste, this article describes a recyclebot, which is a waste plastic extruder capable of making commercial quality 3-D printing filament. The device design takes advantage of both the open source hardware methodology and the paradigm developed by the open source self-replicating rapid prototyper (RepRap) 3-D printer community. Specifically, this paper describes the design, fabrication and operation of a RepRapable Recyclebot, which refers to the Recyclebot’s ability to provide the filament needed to largely replicate the parts for the Recyclebot on any type of RepRap 3-D …

Gait Modeling Using Genetic Algorithm Optimized Four-Bar Linkages, Hazen James Hamather

Graduate Theses - Mechanical Engineering

Important in diagnosing gait abnormalities and pathologies is knowing the position of the leg at various points throughout the gait cycle. This is currently done with motion capture technology but the demand for Inertial Measurement Unit (IMU) based navigation and position tracking has been on the rise. A required component of this alternative is a gait model that can accurately predict the position of points of interest. In this thesis, a Kalman Filter is constructed using a contrived model to test if, given an accurate gait model, the filter can converge to an accurate and true position solution. Also presented …

A Human Powered Micro-Generator For Charging Electronic Devices, John Adam

Senior Theses

A hand-pulled generator has been designed and tested. A preliminary result has been obtained and discussed. This device was created to provide outlet-free charging. Electronic devices are useful when going out into the wilderness. A portable power supply is necessary to keep an electronic device alive. This project created a device that converts human energy into electricity to charge electronic devices. This thesis overviews the device’s design, build, and tests. Two different tests were run to determine that the device is capable of charging the storage battery. The device presented can provide 14 minutes of charging time with one hour …

Effects Of Tension On Resonant Frequencies Of Strings, Blake Burnett

Senior Theses

This project tests and explores resonance of strings. Since all materials and mechanisms are affected by vibrations, it is important to know the frequencies at which resonance occurs. To explore this subject, strings were used as a model material to test the effect tension has on resonance. The fundamental frequencies and the corresponding modes of resonance were used to analyze the data. The results of this experiment show that increasing tension on a string increases its resonance frequency. Understanding the physics behind resonance frequency allows systems to be designed to take advantage of resonance properties, or to avoid resonance where …

Increasing The Longevity Of Tungsten Filaments In A Zone Refiner, Byron D. Greenlee

Senior Theses

Zone refining is used for its ability to purify material and grow single crystals. To produce these single crystals, a suspended molten zone, generated by electron bombardment, passes along the polycrystalline stock. During a zone refining run, the filaments that produce the electron bombardment can fail. In this project, the longevity of tungsten filaments in a zone refiner was investigated. A new bombardment geometry was constructed to attempt to increase the longevity of the filaments. The new geometry had a shield machined into it to prevent line-of-sight impurities originating in the molten zone from striking the filaments. It was found …

Measuring The Double Layer Capacitance Of Electrolyte Solutions Using A Graphene Field Effect Transistor, Agatha Ulibarri

Senior Theses

When operating graphene field effect transistors (GFETs) in fluid, a double layer capacitance (C_dl) is formed at the surface. In the literature, the C_dl is estimated using values obtained using metal electrode experiments. Due to the distinctive electronic and surface properties of graphene, there is reason to believe these estimates are inadequate. This work seeks to directly characterize the double layer capacitance of a GFET. A unique method for determining the C_dl has been implemented, and data has been obtained for three electrolytes and one ionic fluid. The results yield dramatically lower C_dl values than …

The Effects Of Surface Pace In Baseball, Jason Farlow

Senior Theses

A baseball travels across different surfaces at different paces. The goal of this experiment is to find a percentage difference in speeds the ball will reflect off a given surface. The energy lost on the turf surface was far more significant than on dirt surface as the turf lost an average of 26% of its energy as compared to just 16% of the energy on dirt. In the Northwest conference, teams play on four turf-based infields and five dirt-based infields. The results of this study suggest that kinetic friction forces are more significant in reducing ball rebound speed than in …

The Drag Coefficient Of Varying Dimple Patterns, James M. Seeley, Michael S. Crosser

Senior Theses

There are many golf balls on the market today with varying dimple sizes, shapes, and distribution. These proprietary differences are all designed to reduce drag on the balls during flight, allowing golfers to hit the ball farther distances. There are limited published studies comparing how varying the dimples affects the reduction of drag. An experiment was developed in which golf balls were pulled through a water tank to measure the drag force acting on each ball. The water was chosen to allow for testing at slower velocities than the typical necessary speeds to cause turbulence for balls traveling in air. …

Measuring The Double Layer Capacitance Of Electrolytes With Varied Concentrations, Geoffrey Rath

Senior Theses

When electric potentials are applied from an electrolytic fluid to a metal, a double layer capacitor, C_dl, develops at the interface. The layer directly at the interface is called the Stern layer and has a thickness equal to roughly the size of the ions in the fluid. The next layer, the diffuse layer, arises from the gathering of like charges in the Stern layer. This layer is the distance needed for ionic charges to return to equilibrium. This distance, called the Debye length, λ, depends on the square root of the electrolyte concentration. To study the properties of …

Creativity As A Graduate Attribute, Caitriona Quinn

Other resources

This position paper examines the value, delivery and assessment of creativity as a graduate attribute in civil engineering. Creativity is an essential skill for modern civil engineering graduates to allow them to respond to the variety of challenges within the industry. In addition, the need for creativity within their work is both directly and indirectly referenced within accreditation requirements from engineering professional bodies. How to deliver on creativity as a learning outcome requires time and space within the timetable, a difficult challenge in the technical content heavy subjects the make up civil engineering programmes. Added to this are the difficulties …

Effect Of Silk-Based Hydrogel Topography On Intestinal Epithelial Cell Morphology And Wound Healing In Vitro, Marisa E. Boch

University Scholar Projects

Recent advances in the field of biomaterials have suggested that cells cultured on substrates resembling the native tissue mechanical properties, matrix and growth factor composition, and topography can adopt phenotypes that more closely resemble the in vivo tissue compared to cells cultured on non-mimetic constructs. Understanding the effect of culture substrate on in vitro tissue formation is important for bioengineering applications that include mechanistic studies of healthy tissue function and development of disease models. In this work, Caco-2 adenocarcinoma cells were seeded on flat and crypt-like topographies of 3D-printed cytocompatible hydrogels derived from silk fibroin protein. Silk hydrogels were selected …

A Review Of Subsidence Measurements Near Mendota, California, Tom Mastin, Stuart Styles, Kyle Feist

BioResource and Agricultural Engineering

The image of Dr. Poland of the United States Geological Survey (USGS) standing next to a marked powerline in 1977 is circulated as a striking example of land subsidence. This and other historical data are common references for modern subsidence studies. Because of the significance of this data, recent work was conducted to analyze the historical data as well as independently measure the magnitude of subsidence since 1975, within the same study area southwest of Mendota, CA. The results indicate that local subsidence in the area of the photo is less than 0.5 meters between 1975 and 2017. Furthermore the …

Case Study: Flow Measurement And Control In Walker River Irrigation District, Stuart Styles, Sierra Layous, Robert Bryan

BioResource and Agricultural Engineering

Walker River Irrigation District (WRID) is located in Nevada around the community of Yerington and contains approximately 95,000 hectares (235,000 acres), 32,000 hectares (80,000 acres) of which are irrigated. The district operates a canal system centered around the three forks of the Walker River. Starting in 2009, the district has worked with the Irrigation Training and Research Center (ITRC) to modernize its system by improving the accuracy of the measured diversions from the Walker River and enhancing the real-time control capabilities of the water managers. A “package” was developed for the headworks of canals diverting water from the river, consisting …

Evaluation Of A Substitute Structure Method To Estimate Seismic Displacement Demand In Piers And Wharves, Rakesh K. Goel

Civil and Environmental Engineering

This paper compares seismic displacement from the MOTEMS and the ASCE/COPRI 61-14 substitute structure method (SSM) with results from the nonlinear response history analysis (NLRHA). It is found that the SSM is biased toward overpredicting displacement demand for short-period systems and under-predicting displacement demand for long-period systems. The overprediction was found to be excessive for very-short period systems (i.e., systems with periods shorter than the period at which the design spectrum transitions from linearly increasing spectral acceleration to constant spectral acceleration). It is recommended that the SSM not be used for such systems. It is also recommended that the SSM …

An Embarrassment Of Riches: Data Integration In Vr Pompeii, Adam Schoelz

Computer Science and Computer Engineering Undergraduate Honors Theses

It is fair to say that Pompeii is the most studied archaeological site in the world. Beyond the extensive remains of the city itself, the timing of its rediscovery and excavation place it in a unique historiographical position. The city has been continuously studied since the 18th century, with historians and archaeologists constantly reevaluating older sources as our knowledge of the ancient world expands. While several studies have approached the city from a data driven perspective, no studies of the city have taken a quantitative holistic approach on the scale of the VR Pompeii project. Hyper-specificity has been the order …

Training Machine Learning Agents In A 3d Game Engine, Diego Calderon

Computer Science and Computer Engineering Undergraduate Honors Theses

Artificial intelligence (AI) and video games benefit from each other. Games provide a challenging domain for testing learning algorithms, and AI provides a framework to designing and implementing intelligent behavior, which reinforces meaningful play. Medium and small studios, and independent game developers, have limited resources to design, implement, and maintain agents with reactive behavior. In this research, we trained agents using machine learning (ML), aiming to find an alternative to expensive traditional algorithms for intelligent behavior used in video games. We use Unity as a game engine to implement the environments and TensorFlow for the neural network training.

High Temperature Wide Bandgap Light Emitting Diodes For Harsh Environment Applications, Stephanie Sandoval

Electrical Engineering Undergraduate Honors Theses

The need for high temperature, high power density power modules for applications such as electric vehicles and space exploration has driven the research into wide bandgap LEDs due to their potential operation at elevated temperatures. Wide bandgap LEDs offer an attractive solution due to properties such as high temperature tolerance, strong radiation hardness and good thermal conductivity. In this thesis, the electrical properties of GaN-on-SiC heterojunctions are studied as a precursor to an LED study, and the optical characterization of an InGaN/GaN MQW is reported. The GaN-on-SiC study revealed that these wide bandgap LEDs have linear sensitivity at high temperatures. …

Inspire E-News 05/06 2018, College Of Engineering And Applied Sciences

College of Engineering and Applied Sciences News

• Message from the Dean
• Georgeau Construction Research Center awards grants
• Kujawski recieves ADVANCE grant
• Outstanding students honored at luncheon

Efficient Control Message Dissemination In Dense Wireless Lighting Networks, Conrad Dandelski

PhDs

Modern lighting systems using LED light sources lead to dense lighting installations. The control of such systems using wireless Machine-to-Machine (M2M) where standard LED light sources are replaced by wirelessly controllable LED light sources create new problems which are investigated in this thesis. Current approaches for control message transmission is such networks are based on broadcasting messages among luminaires. However, adequate communication performance - in particular, sufficiently low latency and synchronicity - is difficult to ensure in such networks, in particular, if the network is part of a wireless building management system and carries not only low-latency broadcast messages but …

Mitigating The Structural Vibrations Of Wind Turbines Using Tuned Liquid Column Damper Considering Soil-Structure Interaction, Tadhg Buckley, Phoebe Watson, Paul Cahill, Vesna Jaksic, Vikram Pakrashi

Publications

This paper considers the potential of using a Tuned Liquid Column Damper (TLCD) to reduce structural vibrations of a wind turbine tower. The effect of TLCD on wind turbine towers, including the soil-structure interactions for a monopile foundation was modelled theoretically and scaled laboratory experiments were carried out to validate these results. The tower of the turbine is represented as a Euler beam with a set of springs at the boundary to simulate the soil-structure interaction. TLCD design was carried out using such a model and the reduction in tower vibrations due to the deployment of TLCD was then examined …

A Numerical Investigation Of Bio-Inspired Scaffolds And Surface Textures, Yucong Gu

Graduate Theses and Dissertations

Synthetic scaffolds are widely used as implants to repair bone fracture. Without a proper design, scaffolds could pose significant health risks to the patient and fail to heal the bone properly. A good synthetic scaffold needs to have high porosity and large pore size to allow new bone cells to form on it. However, a scaffold with higher porosity and larger pore size tends to have reduced mechanical strength. Thus, it is important to find a structural design which allows the implant to have a high porosity and large pore size while retaining high strength. In this research, a 3D-printable …

Mesoscale Computational Studies Of Thin-Film Bijels, Joseph M. Carmack

Graduate Theses and Dissertations

Bijels are a relatively new class of soft materials that have many potential applications in the technology areas of energy, medicine, and environmental sustainability. They are formed by the arrest of binary liquid spinodal decomposition by a dispersion of solid colloidal nanoparticles. This dissertation presents an in-depth simulation study of Bijels constrained to thin-film geometries and in the presence of electric fields. We validate the computational model by comparing simulation results with previous computational modeling and experimental research. In the absence of suspended particles, we demonstrate that the model accurately captures the rich kinetics associated with diffusion-based surface-directed spinodal decomposition. …

Liquefaction-Induced Dragload And/Or Downdrag On Deep Foundations Within The New Madrid Seismic Zone, Ishimwe Elvis

Graduate Theses and Dissertations

Deep foundation elements are typically used to transfer structural loads for multi-story buildings and large-span bridges to a competent soil layer when 1) the soil close to the ground surface has no sufficient bearing capacity, and when 2) liquefiable soils are encountered. The majority of the bridges constructed within seismic zones rely upon the stability of earthen embankments and deep foundation that are installed above or within liquefiable soil deposits. Despite large factor of safety values or different load and resistance factors being used to adequately design deep foundations within seismic areas, soil liquefaction may cause extensive damage to the …

Effects Of Surface-Directed Spinodal Decomposition On Binary Thin-Film Morphology, Michael Brian Wise

Graduate Theses and Dissertations

Preferential wetting can have a significant impact on the kinetics of phase separation in certain systems. The depletion of the wetting component can simply alter domain growth rates or change the structure entirely. In this thesis, we employ a Cahn-Hilliard model to study the evolution of binary thin-films with symmetric surface wetting. Three possible morphologies were identified: discrete, bicontinuous, and a novel quasi-2D bicontinuous structure in which both phases retain continuity throughout the volume as well as on the center xy plane. Using a continuity factor, regions of film thickness versus blend composition were classified as producing a certain morphology. …

Microheater Array Powder Sintering (Maps) For Printing Flexible Electronics, Nicholas Holt

Graduate Theses and Dissertations

Microheater array powder sintering (MAPS) is a novel additive manufacturing process that uses an array of microheaters to selectively sinter powder particles. MAPS shows great promise as a new method of printing flexible electronics by enabling digital curing of conductive inks on a variety of substrates. MAPS operation relies on establishing a precision air gap of a few microns between an array of microheaters, which can reach temperatures of 600°C, and a layer of conductive ink which can be deposited onto a flexible substrate. This system presents challenges, being: the fabrication of a microheater that can reach suitable temperatures in …