Engineering Commons^™

3d Printed Bone Supplement Materials, Azem Khalifa Yahamed

Dissertations

Three-dimensional (3D) printing is an advanced rapid technology that can be used to make human bone substitutes with exact shape and designed structures, based on models created from actual individual bone medical Digital Imaging and Communications in Medicine (DICOM) images. Biocompatible polymers have been selected for 3D printing of human bone structures. The thermoplastics were 3D printed with Fused Deposition Modeling (FDM) are Acrylate Butadiene Styrene (ABS), Polylactic Acid (PLA) and ULTEM 9085 (a polyetherimide). The polyamide PA 2200 was 3D printed using Selective Laser Sintering (SLS). Digital ABS (a crosslinked acrylic polymer) was 3D printed using PolyJet Technology. These …

Data Quality Challenges In Distributed Live-Virtual-Constructive Test Environments, Jeremy R. Millar, Douglas D. Hodson, Gilbert L. Peterson, Darryl K. Ahner

Faculty Publications

Live-Virtual-Constructive (LVC) simulations are complex systems comprising a combination of live (real people operating real equipment), virtual (real people operating simulated equipment or vice versa), and constructive (wholly simulated) entities. Nodes in the system support the simulation of one or more entities and are often geographically distributed to leverage unique assets (e.g., physical test range space or high-fidelity full motion simulators). Abstract excerpt © ACM

Acoustical Society Of America Helmholtz-Rayleigh Interdisciplinary Silver Medal In Physical Acoustics, Biomedical Acoustics, And Engineering Acoustics: Armen Sarvazyan, E. Carr Everbach, L. A. Crum

Engineering Faculty Works

The Silver Medal is presented to individuals, without age limitation, for contributions to the advancement of science, engineering, or human welfare through the application of acoustic principles, or through research accomplishment in acoustics.

Effects Of Curing Cycle And Loading Rates On The Bearing Stress Of Double Shear Composite Joints, Mateja Andrejic

Master's Theses

In the last few decades, there has been a shift to using more lightweight materials for the potential of fuel consumption reduction. In the Aerospace Industry, conventional metal structures are being replaced by advanced composite structures. The major advantage of an advanced composite structure is the huge reduction in the number of parts and joints required. Also composite materials provide better resistance to creep, corrosion, and fatigue. However, one cannot eliminate all the joints and attachments in an aircraft’s structure. Eliminating structural joints is impractical in present-day aircraft because of the requirements for inspection, manufacturing breaks, assembly and equipment access, …

Syllabus: Space Systems Engineering 122 (Satellites And Space Systems Ii), Robert J. Twiggs

Robert "Bob" Twiggs STEM Education Collection

A syllabus created by Professor Bob Twiggs for Space Systems Engineering 122 (Satellites and Space Systems II) taught at Morehead State University in the Spring of 2016.

Design And Prototyping Of A Variable Geometry Extrusion Die To Exhibit Significant Alteration Of Shape, David C. Bell

Honors Theses

Extruded parts are conventionally made by forcing melted plastic through a steel die having a fixed opening that matches the shape of the part. Plastic parts made by extrusion include weather stripping, PVC pipe, and composite lumber. Variable geometry dies can change their opening shape during the extrusion process. Developing shape-changing dies technology offers the possibility of making parts with varying cross-sections that currently need to be made through injection molding. This is desirable as, compared to molding, extrusion tends to be faster and less expensive. Variable geometry extrusion dies have been designed and prototyped by the University of Dayton …

Design And Fabrication Of Passive Barium Strontium Titanate (Bst) Thin Film Varactor Based Phase Shifters For Operation Within A 5-15 Ghz Bandwidth, Devin William Spatz

Honors Theses

Two passive, analog phase control circuit designs utilizing ferroelectric varactors are presented. The tuning capabilities of single layer and parallel plate varactors deposited on a Ba0.6Sr0.4TiO3 (BST) thin film are characterized. Phase control is demonstrated through cascading multiple shunt varactors along a coplanar waveguide (CPW) structure. Through the application of a 0V – 8V DC bias, the capacitance in the circuit is tuned to control the transmission phase shift (angle of S21). Simulations of both phase control device structures are performed in AWR Microwave Office and compared with measurement data. Both circuit and mathematical models are developed and compared to …

Nonlinear Analysis Of Balance Data In The Easter Seals Adult Day Services Population, Taylor Marie Schemmel

Honors Theses

81.1 million adults are expected to be affected by dementia in 2040. Individuals with dementia are twice as likely to fall as healthy individuals and three times as likely to sustain an injury during a fall. Unfortunately, current fall prevention techniques in place for cognitively healthy older adults are not as effective for those with dementia. The objective of this study was to examine balance differences between individuals of varying cognitive ability utilizing Easter Seals Adult Day Services. All study participants completed the Montreal Cognitive Assessment (MoCA). Clinical assessments were done in conjunction with static posturography data collection on a …

Phosphorus Adsorption Through Engineered Biochars Produced From Local Waste Products, Peter Ogonek

Honors Theses

Phosphorus contained in agricultural runoff is a major anthropogenic contributor to harmful algal blooms (HABs). Biochars are carbon-based materials produced from the pyrolysis of waste biomass that have the potential to amend soils and remediate inorganic and organic contaminants from water. Engineered biochars tailored to adsorb phosphorus from water could reduce the availability of the nutrient in agricultural runoff, reducing the size and frequency of HABs. This study observed the phosphorus adsorption properties of engineered biochars produced from two source materials, oak sawdust and cornstalk residue, and being unmodified, acid-rinsed, or loaded with magnesium prior to pyrolysis, creating acid-rinsed, unmodified, …

Circle Of Willis Model For Transcranial Doppler Ultrasound Training, Conner J. Beyersdorf, Ben Hage, Greg Bashford

UCARE: Research Products

Transcranial Doppler (TCD) ultrasound is a technique involving the use of high frequency transmitters to measure intracranial blood flow. The brain is supplied by blood in an arterial anastomosis called the Circle of Willis. Using TCD ultrasound on the circle is difficult and requires practice and teaching. A functional model of the Circle of Willis could prove to be a valuable teaching tool. Through the use of AutoCAD and 3D printing software, an anatomically accurate model was created and set in gelatin phantom inside of a plastic skull. Milk was pumped through the model with a peristaltic pump to simulate …

Drag Reduction Using Femtosecond Laser Surface Processing: Experimental Setup, Derek Wallin, Henry Ems, Craig Zuhlke, Dennis R. Alexander, George Gogos, Sidy Ndao

UCARE: Research Products

The experimental setup for developing a system to test the drag effects of different superhydrophorbicities. This is used to revise the current Moody Chart and redefine fluid drag in a pipe.

Fluid drag reduction is important in many applications such as reducing the power requirement to pump a fluid through a channel or pipe. The Center for Electro-Optics and Functionalized Surfaces (CEFS) at the University of Nebraska – Lincoln uses a femtosecond laser to functionalize 304 stainless Steel to become superhydrophilic or superhydrophobic The Processing produces microscale and nanoscale surface roughness that when treated with siloxanes becomes superhydrophobic. Small vortices …

Investigation Of A Nanoparticle Delivery System For Micronutrients In Corn, Zully Perez Sierra, Zachary P. Stewart, Hendrik J. Viljoen

UCARE: Research Products

Pheroid Nanoparticle Delivery System1 • Cost effective for plant applications • Safe – multi-lamellar lipid system derived mostly from soybeans • Versatile – payloads delivered range from micronutrients to antibiotics Micronutrient Deficiency • Caused by the immobility of micronutrients through the plant. • Leads to malnutrition children in poor countries2 • As fertilizers deliver nutrients, only small percentage obtained by plant. Purpose of Nanoparticle Delivery System • Increase plant micronutrient content and yield • Reduces the effects of run-of, overuse and pollution Other Nano-Fertilizer Trials • Desert plant results – in a foliar application versus irrigation application, the foliar nano-fertilizer …

Development Of A Robust Setup For The Study Of Wetting Characteristics Of Low Melting Point Metals, John D. Casias, Ethan Allan Davis, Sidy Ndao

UCARE: Research Products

• Energy use is very inefficient

• Approx. 60% rejected mostly in the form of waste heat

• Low melting point metals are promising for applications in thermal energy management, conversion, and storage

Exploring Large-Scale Parameterization Of Irrigation In The Northern High Plains, Mitch Maguire, Daniel Rico, Katherine Smith, Francisco Munoz-Arriola

UCARE: Research Products

Research Question – Objective - Hypothesis

How does irrigation respond to the demands of Crop Irrigation Requirements under extreme hydrometeorological events?

Implement a parameterization of irrigation into the land surface hydrology model VIC.

Changes in evapotranspiration (ET) will be more conspicuous during dry years, highlighting the limiting role of soil moisture in the model.

Exploring Oculomotor Trends In Collegiate Athletes, Brett Whorley, Julie A. Honaker

UCARE: Research Products

Collaborative efforts to improve athlete safety without significantly hindering the rules of the games aim to develop a novel system to better measure and diagnose concussions. Provided that common signs of concussions include blurred vision, distant gaze, and dizziness, the Dizziness and Balance Disorders Lab at UNL believes that the simple oculomotor exam studied in this project may be applied to this procedure. Within the broader goal to better understand the causes, signs, symptoms, and prognosis of concussions, researchers desired to further investigate the results of this oculomotor test. The aim was to identify and interpret correlations between collegiate athlete …

Ionic Driven Embedment Of Hyaluronic Acid Coated Liposomes In Polyelectrolyte Multilayer Films For Local Therapeutic Delivery, Stephen Lawrence Hayward, David Francis, Matthew J. Sis, Srivatsan Kidambi

UCARE: Research Products

The ability to control the spatial distribution and temporal release of a therapeutic remains a central challenge for biomedical research. Here, we report the development and optimization of a novel substrate mediated therapeutic delivery system comprising of hyaluronic acid covalently functionalized liposomes (HALNPs) embedded into polyelectrolyte multilayer (PEM) platform via ionic stabilization. The PEM platform was constructed from sequential deposition of Poly-LLysine (PLL) and Poly(Sodium styrene sulfonate) (SPS) “(PLL/SPS)4.5” followed by adsorption of anionic HALNPs. An adsorption affinity assay and saturation curve illustrated the preferential HALNP deposition density for precise therapeutic loading. (PLL/SPS)2.5 capping layer on top of the deposited …

Impacts Of Operating Parameters On Extracellular Polymeric Substances Production In A High Rate Activated Sludge System With Low Solids Retention Times, Matthew S. Elliot

Civil & Environmental Engineering Theses & Dissertations

The Adsorption/Bio-oxidation (A/B) process accomplishes carbon capture via bio-flocculation in the adsorption stage (A-stage) to maximize energy recovery while simultaneously providing an optimal carbon to nitrogen (C/N) ratio for denitrification in the Bio-oxidation stage (B-Stage). The present study evaluated the influence of the solids retention time (SRT), dissolved oxygen (DO) concentration, and production of extracellular polymeric substances (EPS) on bio-flocculation and subsequent carbon capture using a pilot-scale A-stage process. A mixed liquor suspended solids (MLSS)-based control strategy was implemented to manage carbon capture by maintaining a constant MLSS concentration of 3,000 mg/L in response to diurnal variations in organic loading. …

Design And Implementation Of A Virtual Team Collaboration System, Syed Ehsan

Engineering Management & Systems Engineering Theses & Dissertations

This paper analyzes a newly developed virtual team collaboration site and compares this application with the currently in use team collaboration tool created using a Google site. Various tests that are essential for a web service to function properly are performed to compare the applications. The tests are aimed to find any issues with the applications and identify if Teamboard ODU, the newly developed application, can perform better than the Google site. We test for speed, performance, usability, functionality and also explore the methodology used to develop the application. These test results allow us to make an informed assumption about …

Investigating The Relationship Between Latent Driving Patterns And Traffic Safety Using Smartphone-Based Mobile Sensor Data, Kenneth Wynne

Civil & Environmental Engineering Theses & Dissertations

Crash frequency modelling has been used in the past as an attempt to quantify the expected number of crashes occurring on a certain segment of roadway given a set of variables and factors describing the roadway segment and the traffic along that segment. These models are referred to as the Safety Performance Functions (SPFs) in the Highway Safety Manual (HSM). In past studies, these SPFs have focused primarily on roadway geometric information along with limited traffic exposure data such as traffic volume. Alternate data sources for probe vehicle data are increasingly available and this research sought to exploit this new …

A Retrospective Study Of Amusement Ride Restraint And Containment Systems: Identifying Design Challenges For Statistically Rare Anthropometric Cases, Paula M. Stenzler

Engineering Management & Systems Engineering Theses & Dissertations

The intent of this project was to conduct a retrospective study of amusement ride restraint and containment systems’ failures to identify the challenges associated with existing design criteria to safely accommodate statistically rare groups that fall outside amusement industry standards. Innovations in ride technology provide an opportunity for injuries to occur if restraint and containment systems cannot properly accommodate unique patron anthropometry. It is paramount to understand how anthropometric features contribute to the patron’s ability to defeat ride restraint and containment systems. A systemic perspective was used based on industry accident data to frame the problem associated with restraint and …

Experimental Analysis Of Turbulent Structures And The Effects Of Non-Equilibrium On An Axial Vortex, Michael P. Thompson

Mechanical & Aerospace Engineering Theses & Dissertations

Examples of the axial vortex include, dust devils, trailing line aircraft wake vortices, and tornadoes. Some of these vortices can prove hazardous to individuals and property. This necessitates that studies be conducted to understand their structure and to attempt to develop mathematical models of the flow physics involved. A wide variety of experimental techniques have been used in the past to study the vortex, with flow visualization and hotwire anemometry being chosen for this experiment. There have been many inadequate mathematical models proposed in the past. The experimental results obtained were compared to the work of Ash, Zardadkhan and Zuckerwar …

Low-Temperature Artificial Maturation Studies Of Type Ii And Type Iii Kerogens: Implications For Biogenic Gas Production, Albert Willy Nguena Kamga

Chemistry & Biochemistry Theses & Dissertations

Ancient organic matter (OM) in shales and coals, known mainly as Type II and Type III OM are known to produce both biogenic, thermogenic gas and oil. In this dissertation, mild artificial maturation, via closed system pyrolysis, is employed to determine the thermal reactivity of Type II and Type III OM beyond diagenesis. We select three Type II kerogens: i) Type II kerogen isolated from recent cores (3.3 Ma, Ro = 0.28) recovered from an upwelling basin in Namibia, Africa referred to as ODP Sediment, ii) Type II-S isolated from sediments (150 Ma, Ro = 0.38) recovered from an outcrop …

Synthesis, Morphological Control, Dispersion Stabilization And In Situ Self-Assembly Of Noble Metal Nanostructures Using Multidentate Resorcinarene Surfactants, Sangbum Han

Chemistry & Biochemistry Theses & Dissertations

In this dissertation, a detailed investigation on the influence of various macrocyclic resorcinarene surfactants in determining the morphology, stabilization and self-assembly of mono- and bi- metallic nanoparticles was undertaken. Chapter 2 describes the influence of resorcinarene surfactants functionalized with amine- and thiol- headgroups in determining the morphology of monometallic Pt nanoparticles synthesized via the Brust-Schiffrin reaction. We found that while resorcinarene benzylthiol can lead to the formation of highly branched Pt nanostructures, resorcinarene amine can lead to the formation of anisotropic crystalline Pt nanoparticles. Further, we have evaluated the influence of resorcinarene ligands in determining the catalytic activity of these …

Plasma Processing Of Superconducting Radio Frequency Cavities, Janardan Upadhyay

Physics Theses & Dissertations

The development of plasma processing technology of superconducting radio frequency (SRF) cavities not only provides a chemical free and less expensive processing method, but also opens up the possibility for controlled modification of the inner surfaces of the cavity for better superconducting properties. The research was focused on the transition of plasma etching from two dimensional flat surfaces to inner surfaces of three dimensional (3D) structures. The results could be applicable to a variety of inner surfaces of 3D structures other than SRF cavities. Understanding the Ar/Cl₂ plasma etching mechanism is crucial for achieving the desired modification of Nb …

Identification Of The Zinc-Oxygen Divacancy In Zno Crystals, Maurio S. Holston, Eric M. Golden, Brant E. Kananen, John W. Mcclory, Nancy C. Giles, Larry E. Halliburton

Faculty Publications

An electron paramagnetic resonance (EPR) spectrum in neutron-irradiated ZnO crystals is assigned to the zinc-oxygen divacancy. These divacancies are observed in the bulk of both hydrothermally grown and seeded-chemical-vapor-transport-grown crystals after irradiations with fast neutrons. Neutral nonparamagnetic complexes consisting of adjacent zinc and oxygen vacancies are formed during the irradiation. Subsequent illumination below ∼150 K with 442 nm laser light converts these (V²⁻_Zn − V²⁺_O)⁰ defects to their EPR-active state (V⁻_Zn − V²⁺_O)⁺ as electrons are transferred to donors. The resulting photoinduced S = 1/2 spectrum of the …

Sustainable Architecture Design: Environmental And Economic Benefits, Michael Babcock

Senior Honors Theses

This thesis examines the movement of environmentalism, and its impact on architecture and construction. During an interview with a professional architect, a basis for research of sustainable design was devised, when he explained that “good” architecture attempts to holistically integrate the external and built environment. Presently, the main measurement for sustainability is energy efficiency. Therefore, architects constantly implement new technology in an attempt to unify both the external and built environment in an energy efficient manner. Furthermore, this thesis provides an environmental and financial cost analysis of implementing sustainable design and build. Research shows that the life cycle and up-front …

Texture Analysis Using The Neutron Diffraction Method On The Non Standardized Austenitic Steel Process By Machining,Annealing, And Rolling, Tri Hardi Priyanto, Parikin Parikin, Meijuan Li

Makara Journal of Technology

Austenitic steel is one type of stainless steel which is widely used in the industry. Many studies on austenitic stainless steel have been performed to determine the physical properties using various types of equipment and methods. In this study, the neutron diffraction method is used to characterize the materials which have been made from minerals extracted from the mines in Indonesia. The materials consist of a granular ferro-scrap, nickel, ferro-chrome, ferro-manganese, and ferro-silicon added with a little titanium. Characterization of the materials was carried out in three processes, namely: machining, annealing, and rolling. Experimental results obtained from the machining process …

Post-Repair Seismic Assessment Of Rc Bridges Damaged With Fractured Column Bars - A Numerical Approach, Ruili He, Yang Yang, Lesley H. Sneed

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

Seismic repair of reinforced concrete (RC) bridge columns has been studied extensively during the past several decades; however, few studies have been conducted on the influence of the column repair (member level) on the post-repair performance of bridge structures (system level). In a previous experimental study by the authors, a method was developed to rapidly repair severely damaged RC bridge columns to enable the quick reopening of the bridge to emergency traffic. Thus, a lower limit state was used for the repair design, so that the lateral strength and drift capacity of a repaired RC column with fractured longitudinal bars …

Strain-Controlled Cyclic Simple Shear Tests On Sand With Radial Strain Measurements, Xin Kang, Louis Ge, Kuang Tsung Chang, Annie On Lei Kwok

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

Strain-controlled cyclic simple-shear tests were performed on silica sand with radial strain measurements. The specimens were tested under a constant K0 condition and subjected to cyclic loading and post cyclic monotonic loading. Threshold cyclic shear strain, volumetric strain, secant shear modulus, and damping ratio are investigated. Generally, the volumetric strain behavior in this study agreed well with literature findings that were investigated using the conventional cyclic direct simple shear test (without radial constraints). Radial strain during monotonic simple shear (post cyclic loading) was found to be a good parameter in monitoring the onset of flow slide in cohesionless soil. The …

The Role Of Household Antimicrobials In The Proliferation Of Antibiotic Resistance During Anaerobic Digestion, Daniel Elliott Carey

Dissertations (1934 -)

Antimicrobial chemicals in consumer personal care products have been found to increase antibiotic resistance in pure culture studies. Although many studies focus on antibiotic resistance development pertinent to medical scenarios, resistance developed in natural and engineered environments might be significant and has become an emerging concern for human health. This dissertation focuses on the antimicrobial chemicals triclosan and triclocarban. These compounds are distinctly different from antibiotics and are used in products like soaps that are labelled as “antibacterial”. Municipal wastewater treatment plants receive triclocarban and triclosan loads higher than most contaminants of emerging concern because they are frequently used in …