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Articles 1441 - 1470 of 4850

Full-Text Articles in Engineering

Minimum Required Detection Range For Detect And Avoid Of Unmanned Aircraft Systems, Jared Kevin Wikle, Tim Mclain, Randal W. Beard, Laith Rasmi Sahawneh Jun 2017

Minimum Required Detection Range For Detect And Avoid Of Unmanned Aircraft Systems, Jared Kevin Wikle, Tim Mclain, Randal W. Beard, Laith Rasmi Sahawneh

Faculty Publications

For unmanned aircraft systems to gain full access to the National Airspace System, they must have the capability to detect and avoid other aircraft. To safely avoid an- other aircraft, an unmanned aircraft must detect the intruder aircraft with ample time and distance to allow the ownship to track the intruder, perform risk assessment, plan an avoidance path, and execute the maneuver. This paper describes two analytical methods for finding the minimum detection range to ensure that these detection and avoidance steps can be carried out. The first method, time-based geometric velocity vectors, includes the bank-angle dynamics of the ownship; …

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Multiple Ngf Treatments Enhance Regeneration In Peripheral Nerves, Keaton Karlinsey, Alonzo Cook Jun 2017

Multiple Ngf Treatments Enhance Regeneration In Peripheral Nerves, Keaton Karlinsey, Alonzo Cook

Journal of Undergraduate Research

The purpose of this project is to develop an effective treatment for damaged nerves. A team led by Dr. Cook has been working in this area for several years. Their project used a combination of biochemical treatments on rats with damaged sciatic nerves to improve the rate and quality of regeneration. The team is comparing the recovery of the nerves through a treatment receiving a combination of Lysophosphatidylcholine (LPC) and Nerve Growth Factor (NGF) with a treatment receiving only NGF and with a control that receives no treatment. LPC has been shown to upregulate the trkA receptor for NGF, thus …

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Development Of Poisson Optical Trap For Volumetric Display, Jeremy Goodsell, Daniel Smalley Jun 2017

Development Of Poisson Optical Trap For Volumetric Display, Jeremy Goodsell, Daniel Smalley

Journal of Undergraduate Research

The purpose of this project was to develop a new type of optical trap based on Poisson’s famous “Poisson Spot” experiment. The two main methods currently for creating a photophoretic trap are to use dark spots created by spherical aberration (see Fig. 1) or to use vortex beams. In the case of a trap caused by spherical aberration which occurs when using spherical lenses to focus a beam, the particle stays in the dark regions due to photophoretic forces [1,2]. Vortex beams are created by doughnut modes of a laser beam. These are modes of the laser which can be …

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Bioreactor Design For Viable Recellularization Of Whole Porcine Kidney, Kennedy Wandelt, Dr. Alonzo Cook Jun 2017

Bioreactor Design For Viable Recellularization Of Whole Porcine Kidney, Kennedy Wandelt, Dr. Alonzo Cook

Journal of Undergraduate Research

Kidney failure affects tens of thousands of individuals annually causing many to rely on dialysis to replace this organ’s function. Most of these individuals are on a waiting list to receive a transplant for years, and unfortunately many die before they are able to reach the top of the list. The bodies of those who do receive kidneys often reject the organs. This rejection can have devastating defects, including mortality. In an effort to change this ongoing cycle we have been researching the idea of creating organs synthesized with the DNA of each specific patient. The process would significantly increase …

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Thermophysical Properties Of Thin Fibers Via Photothermal Quantum Dot Fluorescence Spectral Shape-Based Thermometry, Troy Munro, Liwang Liu, Heng Ban, Christ Glorieux Jun 2017

Thermophysical Properties Of Thin Fibers Via Photothermal Quantum Dot Fluorescence Spectral Shape-Based Thermometry, Troy Munro, Liwang Liu, Heng Ban, Christ Glorieux

Faculty Publications

To improve predictions of composite behavior under thermal loads, there is a need to measure the axial thermophysical properties of thin fibers. Current methods to accomplish this have prohibitively long lead times due to extensive sample preparation. This work details the use of quantum dots thermomarkers to measure the surface temperature of thin fibers in a non-contact manner and determine the fibers’ thermal diffusivity. Neural networks are trained on extracting the temperature of a sample from fluorescence spectra in calibrated, steady-state conditions, based on different spectral features such as peak intensity and peak wavelength. The trained neural networks are then …

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Multi-Fidelity Model Predictive Control Of Upstream Energy Production Processes, Ammon Nephi Eaton Jun 2017

Multi-Fidelity Model Predictive Control Of Upstream Energy Production Processes, Ammon Nephi Eaton

Theses and Dissertations

Increasing worldwide demand for petroleum motivates greater efficiency, safety, and environmental responsibility in upstream oil and gas processes. The objective of this research is to improve these areas with advanced control methods. This work develops the integration of optimal control methods including model predictive control, moving horizon estimation, high fidelity simulators, and switched control techniques applied to subsea riser slugging and managed pressure drilling. A subsea riser slugging model predictive controller eliminates persistent offset and decreases settling time by 5% compared to a traditional PID controller. A sensitivity analysis shows the effect of riser base pressure sensor location on controller …

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Aerodynamic Drag On Intermodal Rail Cars, Philip Donovan Kinghorn Jun 2017

Aerodynamic Drag On Intermodal Rail Cars, Philip Donovan Kinghorn

Theses and Dissertations

The freight rail industry is essential to the US infrastructure and there is significant motivation to improve its efficiency. The aerodynamic drag associated with transport of commodities by rail is becoming increasingly important as the cost of diesel fuel increases. For intermodal railcars a significant amount of aerodynamic drag is a result of the large distance between containers that often occurs and the resulting pressure drag resulting from the separated flow that results due to their non-streamlined shape. This thesis reports on research that has been done to characterize the aerodynamic drag on intermodal train builds and allow their builds …

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An Analysis Of Enabling Techniques For Highly-Accessible Low-Cost Virtual Reality Hardware In The Collaborative Engineering Design Process, Joshua Q. Coburn Jun 2017

An Analysis Of Enabling Techniques For Highly-Accessible Low-Cost Virtual Reality Hardware In The Collaborative Engineering Design Process, Joshua Q. Coburn

Theses and Dissertations

While there currently exists a great deal of research in the literature demonstrating various engineering applications for virtual reality (VR) and the benefits of these applications, VR adoption has been slow in part because of the high cost and resources required to setup and maintain the hardware for these applications. However, in the last 5 years, a new generation of VR hardware has emerged with cost and resource requirements which are a small fraction of previous hardware. This work begins with a survey of this newly available hardware summarizing recent advances for providing virtual input to all of the five …

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How The Choice Of Bed Material Load Equations And Flow Duration Curves Impacts Estimates Of Effective Discharge, Michael James Cope Jun 2017

How The Choice Of Bed Material Load Equations And Flow Duration Curves Impacts Estimates Of Effective Discharge, Michael James Cope

Theses and Dissertations

The purpose of this study is to analyze how estimates of an important geomorphic parameter, effective discharge, are impacted by the choice of bed material load equations and flow duration curves (FDCs). The Yang (1979), Brownlie (1981), and Pagosa equations developed by Rosgen (2006) were compared for predicting bed material load. To calculate the bed material load using the Pagosa equations, the bedload and suspended load are calculated separately and the results are added together. To compare the effectiveness of the equations, measured bed material load data from the USGS Open-File Report 89-67 were used. Following the calculations, the equation …

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In Situ Characterization Of Voids During Liquid Composite Molding, Brock Don Zobell Jun 2017

In Situ Characterization Of Voids During Liquid Composite Molding, Brock Don Zobell

Theses and Dissertations

Global competition is pushing the composites industry to advance and become more cost effective. Liquid Composite Molding or LCM is a family of processes that has shown significant promise in its potential to reduce process times and cost while maintaining high levels of part quality. However, the majority of research and information on composite processes have been related to prepreg-autoclave processing which is significantly different than LCM. In order for LCM processes to gain large scale implementation, significant research is required in order to model and simulate the unique nature of the resin infusion process. The purpose of this research …

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The Effects Of Tether Placement On Antibody Stability On Surfaces, Thomas A. Knotts, Rebecca W. Grawe Jun 2017

The Effects Of Tether Placement On Antibody Stability On Surfaces, Thomas A. Knotts, Rebecca W. Grawe

Faculty Publications

Despite their potential benefits, antibody microarrays have fallen short of performing reliably and have not found widespread use outside of the research setting. Experimental techniques have been unable to determine what is occurring on the surface of an atomic level, so molecular simulation has emerged as the primary method of investigating protein/surface interactions. Simulations of small proteins have indicated that the stability of the protein is a function of the residue on the protein where a tether is placed. The purpose of this research is to see whether these findings also apply to antibodies, with their greater size and complexity. …

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Estimation Of Size And Rotations Of Icebergs From Historical Data Utilizing Scatterometer Data, Jeffrey Scott Budge Jun 2017

Estimation Of Size And Rotations Of Icebergs From Historical Data Utilizing Scatterometer Data, Jeffrey Scott Budge

Theses and Dissertations

In this thesis, the development and methodology of a new, consolidated BYU/NIC Antarctic Iceberg Tracking Database is presented. The new database combines data from the original BYU daily iceberg tracking database derived from scatterometers, and the National Ice Center's weekly Antarctic iceberg tracking database derived from mostly optical and infrared sensors. Using this data, interpolation methods and statistical analyses of iceberg locations are discussed. The intent of this database is to consolidate iceberg location data in order to increase accessibility to users.Active microwave remote sensing instruments are used to track tabular icebergs and provide a daily estimate of their positions …

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A Survey Of Sparse Channel Estimation In Aeronautical Telemetry, Christopher James Hogstrom Jun 2017

A Survey Of Sparse Channel Estimation In Aeronautical Telemetry, Christopher James Hogstrom

Theses and Dissertations

Aeronautical telemetry suffers from multipath interference, which can be resolved through the use of equalizers at the receiver. The coefficients of data-aided equalizers are computed from a channel estimate. Most channels seen in aeronautical telemetry are sparse, meaning that most of the coefficients of the channel are zero or nearly zero. The maximum likelihood (ML) estimate does not always produce a sparse channel estimate. This thesis surveys a number of sparse estimation algorithms that produce a sparse channel estimate and compares the post-equalizer bit error rates (BER) using these sparse estimates with the post-equalizer BER using the ML estimate. I …

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Flexible Micro-N-Line Probe And Apparatus To Characterize Electronic Conductivity Of Li-Ion Battery Electrode Films, Derek Van Clement Jun 2017

Flexible Micro-N-Line Probe And Apparatus To Characterize Electronic Conductivity Of Li-Ion Battery Electrode Films, Derek Van Clement

Theses and Dissertations

A key metric that affects Li-ion battery cell performance is the electronic conductivity of the electrode films. Previous research has found that the conductivity of electrodes is not homogeneous throughout the entirety of the deposited film area. To further characterize the non-homogeneity of the conductivity of electrode films, a micro-N-line probe and a micro-flex-line probe were developed to take micro-scale conductivity measurements of thin-film battery electrodes in a non-destructive manner. These devices have been validated by comparing test results to those of it's predecessor, the micro-four-line probe, on various commercial-quality Li-ion battery electrodes. Results show that there is significant variation …

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Metallization Of Self-Assembled Dna Templates For Electronic Circuit Fabrication, Bibek Uprety Jun 2017

Metallization Of Self-Assembled Dna Templates For Electronic Circuit Fabrication, Bibek Uprety

Theses and Dissertations

This work examines the deposition of metallic and semiconductor elements onto self-assembled DNA templates for the fabrication of nanodevices. Biological molecules like DNA can self-assemble into a variety of complex 2-D and 3-D architectures without the need for expensive patterning tools. In addition, self-assembled DNA templates can be designed to controllably place functional nanomaterials with molecular precision. These characteristics make DNA an attractive template for fabricating electronic circuits from biological molecules. However, electrically conductive structures are required for electronic applications. While metallized DNA nanostructures have been demonstrated, the ability to make thin, continuous wires that are electrically conductive still represents …

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The Application Of Artificial Neural Networks For Prioritization Of Independent Variables Of A Discrete Event Simulation Model In A Manufacturing Environment, Rebecca Pires Dos Santos Jun 2017

The Application Of Artificial Neural Networks For Prioritization Of Independent Variables Of A Discrete Event Simulation Model In A Manufacturing Environment, Rebecca Pires Dos Santos

Theses and Dissertations

The high complexity existent in businesses has required managers to rely on accurate and up to date information. Over the years, many tools have been created to give support to decision makers, such as discrete event simulation and artificial neural networks. Both tools have been applied to improve business performance; however, most of the time they are used separately. This research aims to interpret artificial neural network models that are applied to the data generated by a simulation model and determine which inputs have the most impact on the output of a business. This would allow prioritization of the variables …

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Development Of A Performance-Based Procedure To Predict Liquefaction-Induced Free-Field Settlements For The Cone Penetration Test, Mikayla Son Hatch Jun 2017

Development Of A Performance-Based Procedure To Predict Liquefaction-Induced Free-Field Settlements For The Cone Penetration Test, Mikayla Son Hatch

Theses and Dissertations

Liquefaction-induced settlements can cause a large economic toll on a region, from severe infrastructural damage, after an earthquake occurs. The ability to predict, and design for, these settlements is crucial to prevent extensive damage. However, the inherent uncertainty involved in predicting seismic events and hazards makes calculating accurate settlement estimations difficult. Currently there are several seismic hazard analysis methods, however, the performance-based earthquake engineering (PBEE) method is becoming the most promising. The PBEE framework was presented by the Pacific Earthquake Engineering Research (PEER) Center. The PEER PBEE framework is a more comprehensive seismic analysis than any past seismic hazard analysis …

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Measuring The Robustness Of Forensic Tools' Ability To Detect Data Hiding Techniques, Samuel Isaiah Moses Jun 2017

Measuring The Robustness Of Forensic Tools' Ability To Detect Data Hiding Techniques, Samuel Isaiah Moses

Theses and Dissertations

The goal of this research is to create a methodology that measures the robustness and effectiveness of forensic tools' ability to detect data hiding. First, an extensive search for any existing guidelines testing against data hiding was performed. After finding none, existing guidelines and frameworks in cybersecurity and cyber forensics were reviewed. Next, I created the methodology in this thesis. This methodology includes a set of steps that a user should take to evaluate a forensic tool. The methodology has been designed to be flexible and scalable so as new anti-forensic data hiding methods are discovered and developed, they can …

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Cell Attachment To Alginate Hydrogel Structures, Sarah Livingston, Dr. Alonzo Cook May 2017

Cell Attachment To Alginate Hydrogel Structures, Sarah Livingston, Dr. Alonzo Cook

Journal of Undergraduate Research

One of the most pressing needs within the medical community is the demand for transplantable organs. On average, 22 people per day on average die waiting for a transplant. Even if a patient receives an organ, the risks associated with the transplant are high, from the immunosuppressant drugs required to the risk of Graft-versus-host disease (GvHD). If organs could be engineered using a patient’s own cellular material, transplants could take place without the risk of GvHD or the need for immunosuppressants. One of the keys to creating any organ is first building a vascular network that could provide vital nutrients …

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Estimating Human Intent For Physical Human-Robot Co-Manipulation, Eric Townsend, Erich Mielke, David Wingate, Marc D. Killpack May 2017

Estimating Human Intent For Physical Human-Robot Co-Manipulation, Eric Townsend, Erich Mielke, David Wingate, Marc D. Killpack

Faculty Publications

Human teams can be exceptionally efficient at adapting and collaborating during manipulation tasks using shared mental models. However, the same shared mental models that can be used by humans to perform robust low-level force and motion control during collaborative manipulation tasks are non-existent for robots. For robots to perform collaborative tasks with people naturally and efficiently, understanding and predicting human intent is necessary. However, humans are difficult to predict and model. We have completed an exploratory study recording motion and force for 20 human dyads moving an object in tandem in order to better understand how they move and how …

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A Solution To The Problems Of Heart Transpantation, Jeremy Struk, Alonzo Cook May 2017

A Solution To The Problems Of Heart Transpantation, Jeremy Struk, Alonzo Cook

Journal of Undergraduate Research

Ischemic Heart disease, according to the World Health Organization, is the leading cause of death in the USA and abroad.1 As a result of the high incidence of the disease and low transplant availability, the field of tissue engineering offers a promising solution. With the new developments in the field, many exciting treatments are available to help stem the tide of the disease, however; there is still a great need for more viable heart replacements to help patients with end stage heart failure. Tissue engineering offers the solution of creating hearts for patients in need that are constructed using the …

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Continuous Ethanol Production From Synthesis Gas By Clostridium Ragsdalei In A Trickle-Bed Reactor, Mamatha Devarapalli, Randy S. Lewis, Hasan K. Atiyeh May 2017

Continuous Ethanol Production From Synthesis Gas By Clostridium Ragsdalei In A Trickle-Bed Reactor, Mamatha Devarapalli, Randy S. Lewis, Hasan K. Atiyeh

Faculty Publications

A trickle-bed reactor (TBR) when operated in a trickle flow regime reduces liquid resistance to mass transfer because a very thin liquid film is in contact with the gas phase and results in improved gas–liquid mass transfer compared to continuous stirred tank reactors (CSTRs). In the present study, continuous syngas fermentation was performed in a 1-L TBR for ethanol production by Clostridium ragsdalei. The effects of dilution and gas flow rates on product formation, productivity, gas uptakes and conversion efficiencies were examined. Results showed that CO and H2 conversion efficiencies reached over 90% when the gas flow rate was maintained …

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Re-Epithelialization Of Whole Porcine Kidney Scaffold, Evan M. Buckmiller, Alonzo D. Cook May 2017

Re-Epithelialization Of Whole Porcine Kidney Scaffold, Evan M. Buckmiller, Alonzo D. Cook

Journal of Undergraduate Research

An estimated 20 million adults (approximately 10% of all individuals over the age of 18) in the United States suffer from some level of chronic kidney disease (CKD), making CKD the 9th leading cause of death in the United States (1). The only successful treatment for end-stage renal failure is transplantation from a donor with similar blood antigen makeup, while living the remainder of their lives receiving immunosuppressive therapy. Unfortunately, individuals awaiting a kidney transplant outnumber viable donations. Scientists have been tasked with discovering and developing methods to answer this growing need. One promising method is the decellularization of porcine …

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Preliminary Study Of Optimization Of Normal Pulse Voltammetry For Actinide Measurement In Molten Salt Electrorefiners Using Licl-Kcl-Ucl3-Mgcl2 As A Surrogate Salt, Chao Zhang, Devin Rappleye, Michael Simpson May 2017

Preliminary Study Of Optimization Of Normal Pulse Voltammetry For Actinide Measurement In Molten Salt Electrorefiners Using Licl-Kcl-Ucl3-Mgcl2 As A Surrogate Salt, Chao Zhang, Devin Rappleye, Michael Simpson

Faculty Publications

Normal pulse voltammetry has been applied and optimized to develop correlations between diffusional current and concentration for UCl3 and MgCl2 in molten eutectic LiCl-KCl. This method was selected to mitigate working electrode area growth in concentrated molten salt mixtures in which a fairly wide potential range is needed to analyze all actinides. MgCl2 has been selected as a surrogate for PuCl3 based on similar standard reduction potential. Diffusional current plateaus were successfully attained by adjusting the step size to 0.03 V. Relaxation time of 15 seconds was found to be sufficient to recover after each pulse. …

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Uncertainty Quantification And Propagation Of Errors Of The Lennard-Jones 12-6 Parameters For N-Alkanes, Richard A. Messerly, Thomas A. Knotts Iv, W Vincent Wilding May 2017

Uncertainty Quantification And Propagation Of Errors Of The Lennard-Jones 12-6 Parameters For N-Alkanes, Richard A. Messerly, Thomas A. Knotts Iv, W Vincent Wilding

Faculty Publications

Molecular simulation has the ability to predict various physical properties that are difficult to obtain experimentally. For example, we implement molecular simulation to predict the critical constants (i.e., critical temperature, critical density, critical pressure, and critical compressibility factor) for large n-alkanes that thermally decompose experimentally (as large as C48). Historically, molecular simulation has been viewed as a tool that is limited to providing qualitative insight. One key reason for this perceived weakness in molecular simulation is the difficulty to quantify the uncertainty in the results. This is because molecular simulations have many sources of uncertainty that propagate …

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A Handy Underwater Solution, Benjamin Murdoch, Matt Ricks, Ales Ball, Jacob Olson, Ethan Durrant, Connor Monson, Lars Watts, Mark Killpack May 2017

A Handy Underwater Solution, Benjamin Murdoch, Matt Ricks, Ales Ball, Jacob Olson, Ethan Durrant, Connor Monson, Lars Watts, Mark Killpack

Journal of Undergraduate Research

Hod Lipson once asked an audience at TED, “Where are the robots?” We’ve been waiting for them a long time now and modern robotics still hasn’t caught up with our hopes and dreams. Through our research we hope to address one of the major topics in robotics: movement (or kinematics), and use this moment of exploration to build a new low cost robotic hand capable of use within the exciting realm of aquatics.

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Thermally Stable Support For Improved Synthetic Fuel Catalysts, Mark Lindsay, Dr. William Hecker, Dr. Morris Argyle May 2017

Thermally Stable Support For Improved Synthetic Fuel Catalysts, Mark Lindsay, Dr. William Hecker, Dr. Morris Argyle

Journal of Undergraduate Research

Fischer-Tropsch Synthesis (FTS) has attracted interest recently as large natural gas deposits have been discovered across the globe. FTS is a gas-to-liquid technology that produces fuels with far fewer sulfur or nitrogen impurities, making it an attractive cleaner alternative to petroleum fuels[1]. Cobalt is the preferred catalyst for FTS[2], but it must be supported to achieve optimal performance. Alumina and silica have been used independently as colbalt FTS supports[3-4], and in mixtures as supports for other processes, but mixed silica-alumina supports have not been studied for FTS applications[5]. The BYU Catalysis Lab has discovered a silica-alumina support (AlSi) with high …

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Geogrid-Reinforcement’S Zone Of Influence, Shaun Hilton, W. Spencer Guthrie May 2017

Geogrid-Reinforcement’S Zone Of Influence, Shaun Hilton, W. Spencer Guthrie

Journal of Undergraduate Research

Geogrid is a polypropylene material manufactured with approximately 1-in. wide openings, called apertures. A triaxial geogrid configuration is illustrated in Figure 1. Geogrid reinforcement is typically positioned beneath and/or within an aggregate base layer in a pavement structure and is designed to prevent lateral spreading of the individual aggregate particles comprising that layer. Thus, inter-particle friction can be increased among the individual aggregate particles located above and potentially below the geogrid. When this occurs, the result is an increase in the stiffness of the aggregate base layer that leads to a greater load-carrying capacity of the pavement.

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Insulin, Glucose, And Β-Cell Diffusion Analysis, Matthew Usevitch, Alonzo Cook May 2017

Insulin, Glucose, And Β-Cell Diffusion Analysis, Matthew Usevitch, Alonzo Cook

Journal of Undergraduate Research

The purpose of this project is to further understand the function of extruded polytetrafluoroethylene (ePTFE) membranes in the pursuit of creating an implantable, removable pancreas device. This device would be filled with pancreas cells and automatically regulate blood sugar for patients with diabetes. Dr. Alonzo Cook’s lab is currently pursuing understanding the process of taking a patient’s own cells, reprogramming them into stem cells, and then differentiating them into pancreas cells. The device that is the end goal of this project is the main foreseen use of these differentiated pancreas cells. This project focuses on studying how essential nutrients diffuse …

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Autonomous Identification And Classification Of Targets Using An Unmanned Aerial System, Taylor Mcdonnell, Tim Mclain May 2017

Autonomous Identification And Classification Of Targets Using An Unmanned Aerial System, Taylor Mcdonnell, Tim Mclain

Journal of Undergraduate Research

Commercial applications of unmanned aerial systems (UAS) are expected to grow significantly in the coming years [1]. Applications of unmanned aerial vehicles in the commercial market include agricultural and infrastructure monitoring, aerial photography, package delivery, fire monitoring, wildlife tracking, and search and rescue operations. One of the purposes of the AUVSI-SUAS competition is to train undergraduates for the growing UAS industry. In this competition a team’s UAS must autonomously identify and locate several targets, which are geometric shapes with a given shape, shape color, letter, letter color, geolocation, and orientation. The focus of this project is to develop the image …

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