Engineering Commons^™

Moving Towards Technology Literacy: An Evaluation Of Teachers And Curriculum, Braden Boss, Dr. Geoffrey A. Wright

Journal of Undergraduate Research

Many people struggle defining technology literacy. Some say that there is no “absolute definition of literacy” because technology literacy varies from society to society.1 No matter what society you belong to, how you define technology literacy depends on how you view technology and education.

Small Uavs For Perch And Stare Missions: Ground Locomotion And Self-Launch, Stephen Carlson, Dr. Jerry Bowman

Journal of Undergraduate Research

The mission of this project was the development of an Unmanned Air Vehicle capable of complete autonomy in a terrestrial environment. Using a jumping system for zero-distance take-offs and the addition of ground locomotion devices and energy harvesting systems, the vehicle could operate indefinitely without human assistance. Although this aircraft is unfinished, it and later design attempts have been tested to satisfy the basic fundamentals of this mission. The project will be continued until the stated mission objectives are achieved.

The Development And Refinement Of Constant-Force Mechanisms For Use In Future Applications, Brent L. Weight, Dr. Larry L. Howell

Journal of Undergraduate Research

A compliant mechanism is one in which the mechanism’s motion comes from deflection of one or more of its members. Compliant mechanisms offer several advantages over rigid-body mechanisms. The member deflection characteristic of compliant mechanisms results in the ability to store energy directly within the member, eliminating the need for additional energy storage devices (i.e. springs) found in rigid-body mechanisms. The member deflection also allows for the replacement of pin joints with small length flexural pivots, or living hinges, thereby reducing part count and assembly time. In fact, one of the most significant advantages of compliant mechanisms is their ability …

Freeze-Thaw Effect On Mechanical Properties Of Bovine Ligaments, Alan Bordon, Dr. Anton Bowden

Journal of Undergraduate Research

My ORCA grant proposal was to study the effect that freezing and thawing a soft tissue has on the results of the mechanical property tests (i.e how strong) performed on the tissue. I was to study the effect of a single and multiple freeze/thaw cycles on the tissue. My hypothesis was that there was a deleterious effect and this was important to account for when doing testing with soft tissue.

Compressed Sensing For Sar-Based Wideband Three-Dimensional Microwave Imaging System Using Non-Uniform Fast Fourier Transform, Hamed Kajbaf, Joseph T. Case, Zengli Yang, Yahong Rosa Zheng

Electrical and Computer Engineering Faculty Research & Creative Works

A new compressed sensing (CS) image reconstruction method is proposed for high-resolution wideband three-dimensional synthetic aperture radar (SAR) imaging systems. In contrast to existing CS SAR methods that employ only a forward SAR transform in pre- or post-processing, the proposed method employs both forward SAR and reverse SAR (R-SAR) transforms in each CS iteration to improve the quality of reconstructed images. This study proposes a simple and elegant truncation repair method to combat the truncation error and utilizes non-uniform fast Fourier transform to reduce the SAR and R-SAR transform errors, thereby ensuring the convergence of the CS algorithm and improving …

Directional Phytoscreening: Contaminant Gradients In Trees For Plume Delineation, Matt A. Limmer, Mikhil K. Shetty, Samantha Markus, Ryan Kroeker, Beth L. Parker, Camilo Martinez, Joel Gerard Burken

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

Tree Sampling Methods Have Been Used in Phytoscreening Applications to Delineate Contaminated Soil and Groundwater, Augmenting Traditional Investigative Methods that Are Time-Consuming, Resource-Intensive, Invasive, and Costly. in the Past Decade, Contaminant Concentrations in Tree Tissues Have Been Shown to Reflect the Extent and Intensity of Subsurface Contamination. This Paper Investigates a New Phytoscreening Tool: Directional Tree Coring, a Concept Originating from Field Data that Indicated Azimuthal Concentrations in Tree Trunks Reflected the Concentration Gradients in the Groundwater Around the Tree.To Experimentally Test This Hypothesis, Large Diameter Trees Were Subjected to Subsurface Contaminant Concentration Gradients in a Greenhouse Study. These Trees …

A Forward-Secure Certificate-Based Signature Scheme, Jiguo Li, Huiyun Teng, Xinyu Huang, Yichen Zhang, Jianying Zhou

Faculty Publications

Cryptographic computations are often carried out on insecure devices for which the threat of key exposure raises a serious concern. In an effort to address the key exposure problem, the notion of forward security was first presented by Günther in 1990. In a forward-secure scheme, secret keys are updated at regular periods of time; exposure of the secret key corresponding to a given time period does not enable an adversary to ‘break’ the scheme for any prior time period. In this paper, we first introduce forward security into certificate-based cryptography and define the security model of forward-secure certificate-based signatures (CBSs). …

Fast And Accurate Multiscale Electromagnetic Modeling Framework: An Overview, W. C. Chew, A. C. Cangellaris, J. Schutt-Aine, H. Braunisch, Z. G. Qian, A. A. Aydiner, K. Aygun, L. (Lijun) J. Jiang, Z. H. Ma, L. L. Meng, M. Naeem

Electrical and Computer Engineering Faculty Research & Creative Works

We present an overview of challenge problems in electromagnetic modeling of highly complex and multi-scale structures found in 3D IC, SiP, SoC, and electronic packaging necessary for signal integrity assessment. © 2013 IEEE.

Flow-Induced Crystallization Of Isotactic Polypropylene And Random Polyethylene–Polypropylene Copolymers, Frederic Aubin

Department of Mechanical and Materials Engineering: Dissertations, Theses, and Student Research

Flow-induced crystallization (FIC) has been investigated for decades but the effect of molecular characteristics that hinder crystallization—such as the presence of random comonomers— on FIC remains scarcely explored. Flow greatly enhances crystallization kinetics and can induce the formation of highly oriented morphologies that affect final properties (i.e. stiffness, permeability, thermal conductivity, elastic modulus, etc.). Therefore, understanding FIC remains particularly important for developing predictive models to allow optimization of processing techniques involving flows.

Polypropylene represents ~ 40% of the global polyolefin production. The addition of ethylene comonomer allows their use as engineering plastics because of their particular toughness and flexibility. This …

Incorporating Chemical Activity And Relative Humidity Effects In Regional Air Quality Modeling Of Organic Aerosol Formation, Marguerite Colasurdo Marks

Dissertations and Theses

Atmospheric particulate matter is known to have significant effects on human health, visibility, and global climate. The magnitudes of these effects, however, depend in complex ways on chemical composition, relative humidity, temperature, phase state, and other parameters. Current regional air quality models such as CMAQ (Community Multiscale Air Quality model) ignore many of these considerations, and consider that the formation of secondary organic aerosol (SOA) can be calculated by assuming thermodynamic ideality in the organic particulate matter (OPM) phase as well as negligible uptake of water into the OPM phase. Theoretical predictions and model simulations considering non-ideality and water uptake …

Climate Change Impacts On Streamflow And Subbasin- Scale Hydrology In The Upper Colorado River Basin, Darren L. Ficklin, Edwin P. Maurer, Iris T. Stewert

Civil, Environmental and Sustainable Engineering

In the Upper Colorado River Basin (UCRB), the principal source of water in the southwestern U.S., demand exceeds supply in most years, and will likely continue to rise. While General Circulation Models (GCMs) project surface temperature warming by 3.5 to 5.6uC for the area, precipitation projections are variable, with no wetter or drier consensus. We assess the impacts of projected 21st century climatic changes on subbasins in the UCRB using the Soil and Water Assessment Tool, for all hydrologic components (snowmelt, evapotranspiration, surface runoff, subsurface runoff, and streamflow), and for 16 GCMs under the A2 emission scenario. Over the GCM …

The Determination Of Grain Boundary Structure, Ryan J. Larsen, Dr. Brent L. Adams

Journal of Undergraduate Research

A growing focus of material science research is relating material properties to grain boundary geometry. The purpose of my research has been to improve current methods of determining grain boundary geometry and to relate interface geometry to sensitization of AISI type 304 stainless steel. Sensitization is the formation of chromium carbides that occurs in a temperature range of 500-800 °C, and makes the material more susceptible to intergranular stress corrosion cracking and stress corrosion cracking.

The Effect Of The Duct Area To Rocket Area Ratio And Rocket Expansion On Ejector-Rocket Performance, Michael I. Kellogg, Dr. Russell Daines

Journal of Undergraduate Research

Space is the final frontier. That has been generally believed since Sputnik went up in the 1950’s, but in spite of this optimistic belief, homesteaders have not yet begun to settle Mars, nor have businesses sponsored ventures to other planets. One of the reasons that the final frontier is so quiet is the prohibitive expense of getting there. Currently it cost about $10,000 to launch a pound of payload into low earth orbit.1 NASA, in an effort to lower the cost of launching payloads into space, has been encouraging researchers to develop alternative launch vehicles to replace the Space Shuttle. …

Effects Of Nanocrystal Shape And Size On The Temperature Sensitivity In Raman Thermometry, Liangliang Chen, Kelly Rickey, Qing Zhao, Christopher Robinson, Xiulin Ruan

Birck and NCN Publications

The effects of CdSe nanocrystal (NC) shape and size on the temperature sensitivity of the Raman shift have been investigated, for the interest of Raman thermometry using NCs. For spherical CdSe NCs of diameters 2.8 nm, 3.6 nm, and 4.4 nm, the temperature sensitivities are -0.0131 cm(-1)/K, -0.0171 cm(-1)/K, and -0.0242 cm(-1)/K, respectively. This trend indicates that as the diameter increases, the effect of increasing phonon anharmonicity dominates over the effect of the decreasing thermal expansion coefficient. On the other hand, triangular NCs with a size of 4.2 nm and elongated NCs of a dimension of 4.6 nm by 14 …

Noncontact Operation-State Monitoring Technology Based On Magnetic-Field Sensing For Overhead High-Voltage Transmission Lines, Xu Sun, Qi Huang, Yunhe Hou, Lijun Jiang, Philip W.T. Pong

Electrical and Computer Engineering Faculty Research & Creative Works

This paper proposed a novel noncontact technology of operation-state monitoring based on magnetic-field sensing for high-voltage transmission lines, which can simultaneously measure both electrical and spatial parameters in real time. This technology was derived from research on the magnetic-field distribution at the ground level when the transmission lines operate in different states, including sagging, galloping, and current imbalance. Two typical models of high-voltage three-phase transmission lines were simulated, and the resulting magnetic fields were calculated. The correlation between the magnetic-field variations and the operation states were analyzed. Based on such correlation, a source reconstruction method was developed to reconstruct the …

Assessment - Introduction To Sse-120: Sataellites & Space Systems I, Robert J. Twiggs

Robert "Bob" Twiggs STEM Education Collection

PowerPoint presentation for Introduction to SSE-120: Sataellites & Space Systems I - Assessment given by Bob Twiggs on August 19, 2013 at Morehead State University.

Particle Morphology And Elemental Composition Of Heavy Fuel Oil Ash At Varying Atomization Pressures, Daniel Abraham Tovar

Theses and Dissertations

Land-based turbine engines are currently used to burn heavy fuel oil (HFO), which is a lower cost fuel. HFO contains inorganic material that forms deposits on turbine blades reducing output and efficiency. Magnesium based additives are used to inhibit vanadium pentoxide deposition and reduce the corrosive nature of the gas and deposits in the hot gas path of the gas turbine. The focus of this study was to determine particle morphology and elemental composition of ash when firing HFO in an atmospheric combustor at various fuel injector atomization pressures. Prior to firing, the HFO was washed with water to remove …

A New Approach To Harmonic Elimination Based On A Real-Time Comparison Method, Sri Nikhil Gupta Gourisetti

Theses and Dissertations

Undesired harmonics are responsible for noise in a transmission channel, power loss in power electronics and in motor control. Selective Harmonic Elimination (SHE) is a well-known method used to eliminate or suppress the unwanted harmonics between the fundamental and the carrier frequency harmonic/component. But SHE bears the disadvantage of its incapability to use in real-time applications. A novel reference-carrier comparative method has been developed which can be used to generate an SPWM signal to apply in real-time systems. A modified carrier signal is designed and tested for different carrier frequencies based on the generated SPWM FFT. The carrier signal may …

Gloria Slope Approach - Monitoring Plant Community Changes In Mountain Ecosystems, Jarle I. Holten, Sverre Lundemo, Ph.D.

Guest Lectures

The research described in this presentation is part of the Global Observation Research Initiative in Alpine Environments (GLORIA) whose purpose is to establish and maintain a global, long-term observation network in alpine environments.

Despite changes in mountaintop-vegetation due to recent climate change being observed throughout the world, trends are not consistent. Moreover, as plant communities can be impacted by several different factors, it is important to be able to separate what is due to climate change and what is due to e.g. changes in grazing pressure (see additional file below).

Ceas E-News 08.16.2013, College Of Engineering And Applied Sciences

College of Engineering and Applied Sciences News

Tyler Bayne's Trip to Brazil

Examination Of Material Flow Characteristics In Friction Stir Welding, S. James Felsted, Dr. Tracey W. Nelson

Journal of Undergraduate Research

Friction Stir Welding is a solid state joining process that makes possible the joining of materials that were previously difficult or impossible to weld. A closer examination of friction stir welding shows that welding occurs because of mechanical mixing, frictional heating, and forging. Welds are made on a conventional milling machine that powers a steel tool consisting of a shank, shoulder, and pin (1). This process is being investigated in order to better understand the interaction of the tool with the material and the nature of the material deformation.

Hydrothermal Stability Of The Davisil/Cab-O-Sil Silica Catalyst Carriers, Clint G. Guymon, Dr. Calvin H. Bartholomew

Journal of Undergraduate Research

The Fischer-Tropsch Synthesis (FTS) sustained Germany’s fuel needs during World War II as well as South Africa’s since the 1960’s.1 This catalytic technology is enthralling and left to the interested reader to reap in the deluge of information present in the literature. The principle reaction in FTS is a simple polymerization: nCO + 2nH2 ­ [-CH2-]n + nH2O, over a metal such as iron or cobalt. This paper focuses on the problem of hydrothermal stability of silicasupported cobalt FTS catalyst.

Rectangular Carbon Fiber Isotruss Reinforcement In Concrete Beams, David Jarvis, Dr. David Jensen, Dr. Fernando Fonseca

Journal of Undergraduate Research

The objective of this research was to determine the flexural strength of concrete beams reinforced by the rectangular carbon fiber IsoTruss. The rectangular IsoTruss is a threedimensional composite grid structure patented by Brigham Young University. It is a modification of the regular IsoTruss that is also being researched at Brigham Young University.

Internal Cleave And Fill: A Method For Internal Refinement Of All-Hexahedral Swept Meshes, Michael Borden, Dr. Steven E. Benzley

Journal of Undergraduate Research

Three-dimensional finite element analysis (FEA) is an important design tool for scientists and engineers. Before the analysis can begin, a continuous domain must be subdivided into small elements (i.e., finite elements). The process of subdividing a continuous domain is called meshing. There is currently significant research being devoted to the generation of such meshes. Tetrahedral meshes are well developed and have been incorporated in numerous software packages. Hexahedral meshes provide some advantages over tetrahedral meshes but are currently more restrictive in the geometrical shapes they can fill.[1]

Cyclic Durability Of A Solid Oxide Fe-Air Redox Battery Operated At 650°C, Xuan Zhao, Yunhui Gong, Xue Li, Nansheng Xu, Kevin Huang

Faculty Publications

The recently developed rechargeable solid oxide metal-air redox battery has shown a great potential for applications in mid- to large-scale stationary energy storage. Cyclic durability is one of the most important requirements for stationary energy storage. In this study, we report the cyclic durability of a solid oxide Fe-air redox battery operated at 650°C. The battery was continuously cycled 100 times under a current density of 50 mA/cm² with rather flat performance, producing an average specific energy of 760 Wh/kg-Fe at a round-trip efficiency of 55.5%. The post-test examination indicated that the performance losses could arise from the fuel-electrode …

Cyclic Durability Of A Solid Oxide Fe-Air Redox Battery Operated At 650°C, Xuan Zhao, Yunhui Gong, Xue Li, Nansheng Xu, Kevin Huang

Faculty Publications

The recently developed rechargeable solid oxide metal-air redox battery has shown a great potential for applications in mid- to large-scale stationary energy storage. Cyclic durability is one of the most important requirements for stationary energy storage. In this study, we report the cyclic durability of a solid oxide Fe-air redox battery operated at 650◦C. The battery was continuously cycled 100 times under a current density of 50 mA/cm2 with rather flat performance, producing an average specific energy of 760 Wh/kg-Fe at a round-trip efficiency of 55.5%. The post-test examination indicated that the performance losses could arise from the fuel-electrode of …

Controlled Magnetic Reversal In Permalloy Films Patterned Into Artificial Quasicrystals, Vinayak Shantaram Bhat, J. Sklenar, B. Farmer, J. Woods, Jeffrey Todd Hastings, S. J. Lee, J. B. Ketterson, Lance E. De Long

Physics and Astronomy Faculty Publications

We have patterned novel Permalloy thin films with quasicrystalline Penrose P2 tilings and measured their dc magnetization and ferromagnetic resonance absorption. Reproducible anomalies in the hysteretic, low-field data signal a series of abrupt transitions between ordered magnetization textures, culminating in a smooth evolution into a saturated state. Micromagnetic simulations compare well to experimental dc hysteresis loops and ferromagnetic resonance spectra and indicate that systematic control of magnetic reversal and domain wall motion can be achieved via tiling design, offering a new paradigm of magnonic quasicrystals.

Modeling Power Consumption In Field Programmable Logic Devices, Benjamin L. Bullough, Dr. Michael Wirthlin

Journal of Undergraduate Research

Some of the most important application areas for integrated circuits are in portable communication and computing devices. Since batteries power these devices, power is only available in limited quantities. Optimizing for power allows engineers to produce designs, which extend battery life or use a smaller battery to save volume and weight. The excess heat produced by electrical equipment is also directly related to power consumption and is an important consideration in many applications.

Evaluating Satellite Products For Precipitation Estimation In Mountain Regions: A Case Study For Nepal, Nir Y. Krakauer, Soni M. Pradhanang, Tarendra Lakhankar, Ajay K. Jha

Publications and Research

Precipitation in mountain regions is often highly variable and poorly observed, limiting abilities to manage water resource challenges. Here, we evaluate remote sensing and ground station-based gridded precipitation products over Nepal against weather station precipitation observations on a monthly timescale. We find that the Tropical Rainfall Measuring Mission (TRMM) 3B-43 precipitation product exhibits little mean bias and reasonable skill in giving precipitation over Nepal. Compared to station observations, the TRMM precipitation product showed an overall Nash-Sutcliffe efficiency of 0.49, which is similar to the skill of the gridded station-based product Asian Precipitation-Highly Resolved Observational Data Integration Towards Evaluation of Water …

The Mechanics Of Intracranial Loading During Blast And Blunt Impacts: Experimental And Numerical Studies, Veera Selvan Kuppuswamy

Department of Mechanical and Materials Engineering: Dissertations, Theses, and Student Research

Head injuries in an explosion occur as a result of a sudden pressure changes (e.g. shock-blast) in the atmosphere (primary injury), high velocity impacts of debris (secondary injury) and people being thrown against the solid objects (tertiary injury) in the field. In this thesis, experimental and numerical approaches are used to delineate the intracranial loading mechanics of both primary (blast) and tertiary injuries (blunt).

The blast induced head injuries are simulated using a fluid-filled cylinder. This simplified model represents the head-brain complex and the model is subjected to a blast with the Friedlander waveform type of loading. We measured the …