Engineering Commons^™

Flexural Behavior And Strength Of Doubly-Reinforced Concrete Beams With Hollow Plastic Spheres, Rutvik R. Patel

Civil & Environmental Engineering Theses & Dissertations

This thesis presents the outcome of an investigation into the experimental and theoretical flexural behavior and strength of doubly-reinforced concrete beams with and without hollow plastic spheres. Tests are conducted on two types of beams having simply supported end conditions. To obtain experimental results, a gradually increasing two-point loading is used up to collapse. The experimental load-deflection and load-strain curves are recorded. Theoretical analysis is based on developing non-linear moment-curvature relationships for cross sections with and without hollow spheres. These moment-curvature relationships are then coupled with three separate numerical methods namely, finite difference method, finite integral method and Newmark’s method …

Simplified, Alternative Formulation Of Numerical Simulation Of Proton Exchange Membrane Fuel Cell, Russell L. Edwards

Mechanical & Aerospace Engineering Theses & Dissertations

Three-Dimensional proton exchange fuel cell (PEMFC) operation in steady-state is simulated with computational fluid dynamics / multiphysics software that is based upon the finite-element method. PEMFC operation involves the simultaneous simulation of multiple, interconnected physics involving fluid flows, heat transport, electrochemical reactions, and both protonic and electronic conduction. Modeling efforts have varied by how they treat the physics occurring within and adjacent to the membrane-electrode assembly (MEA). Several approaches treat the MEA as part of the computational domain, solving multiple, and coupled conservation equations via the CFD approach within the 3 regions of the MEA. The thickness dimensions of the …

Non-Invasive Picosecond Pulse System For Electrostimulation, Ross Aaron Petrella

Electrical & Computer Engineering Theses & Dissertations

Picosecond pulsed electric fields have been shown to have stimulatory effects, such as calcium influx, activation of action potential, and membrane depolarization, on biological cells. Because the pulse duration is so short, it has been hypothesized that the pulses permeate a cell and can directly affect intracellular cell structures by bypassing the shielding of the membrane. This provides an opportunity for studying new biophysics. Furthermore, radiating picosecond pulses can be efficiently done by a compact antenna because the antenna size is comparable to the pulse width. However, all of the previous bioelectric studies regarding picosecond pulses have been conducted in …

A Dual Resonant Transformer And A Dielectric Antenna For Picosecond Pulse Radiation, Khiem Huynh

Electrical & Computer Engineering Theses & Dissertations

This thesis discusses the development of a pulsed power system for high power picosecond pulse radiation. In the system, a charging transformer, which generates a high voltage pulse of ~100 kV, can be used for charging a transmission line in less than 100 ns. Such a short pulse could cause a peak gap switch to break down and generate a picosecond pulse transient for radiation. A dielectric antenna, if fed with the high voltage picosecond pulses, can radiate them to targets made of high dielectric materials. Biological tissues, for instance, can be targeted for electrostimulation.

The transformer was designed considering …

The Evaluation Of Enhancing Biological Phosphorus Removal And Improving Settleability Using Mainstream Hydrocyclones For External Selection, Amanda Carrie Ford

Civil & Environmental Engineering Theses & Dissertations

Hydrocyclones, which receive mixed liquor tangentially, separate lighter solids from more dense solids through their tapered shape. Increasing the velocity of liquid as it moves downward allows for the selection of a desired solids fraction. Limited research has been conducted utilizing 20 m³hr^-1 hydrocyclones, with the intent of improving settleability and biological phosphorus removal (Bio-P) for mainstream processes. Improved settleability would allow for increased capacity in the secondary clarifiers which prevents the loss of biomass and subsequent treatment disruption, especially during wet weather scenarios. In addition, treatment intensification can be accomplished by maintaining a higher mixed liquor …

Evaluation Of Social Sustainability Design Aspects In A Recently Developed Student Hostel At Uaeu, Fanan Nssaief Jasim Jameel

Architectural Engineering Theses

In the field of sustainability, the focus is usually on the economic and environmental realms, while the social realm is getting the less attention compared with other realms. This less concern about the social sustainability has been experienced also locally in UAE, where buildings are leaning towards adopting green design approaches but mainly economically and environmentally sustainable. The social variable in student hostels as a type of buildings and micro-communities at the same time is very essential. In UAE, there is a rare focus given to student hostels. This research aims at investigating the social sustainability design aspects in student …

Developing A 1-Megawatt Photovoltaic Power Plant For Liberty University, Andrew Knudsen

Senior Honors Theses

A photovoltaic power plant with a generation capacity of 1-megawatt is designed for Liberty University. Liberty University’s location and size are stated to provide context for the design. Design choices are presented, first with general information that is applicable to any photovoltaic plant design, then with significant factors that impact this design. Specific models of solar panels and inverters are selected after the necessary classifications are determined. The final design has 2,880 solar panels with a fixed angle 30⁰ above the horizon, has two central inverters, and takes up 2.57 acres. Future research is suggested for finances as well as …

Structural And Photoluminescence Properties Of Zno Thin Films Deposited By Ultrasonic Spray Pyrolysis, Iwan Sugihartono, Erfan Handoko, Vivi Fauzia, Artoto Arkundato, Lara Permata Sari

Makara Journal of Technology

Zinc oxide (ZnO) thin films on a silicon (Si) (111) substrate were grown herein using ultrasonic spray pyrolysis at 450 °C with different Zn concentrations. The ZnO thin films had X-ray diffraction patterns of a polycrystalline hexagonal wurtzite structure. The (002) and (101) peak intensities changed under different Zn concentrations. Furthermore, according to Scherer's and Stokes–Wilson equations, the crystallite size and the internal strain of the ZnO thin films in the (002) and (101) peaks changed with the Zn concentration. Optically, the photoluminescence spectra indicated that the ratio of the UV/GB emission of the ZnO thin films was the highest …

Parameter Analysis Of An Adaptive, Fault-Tolerant Attitude Control System Using Lazy Learning, Matthew Russell

Senior Honors Theses

Several key requirements would be met in an ideal fault-tolerant, adaptive spacecraft attitude controller, all centered around increasing tolerance to actuator non-idealities and other unknown quantities. This study seeks to better understand the application of lazy local learning to attitude control by characterizing the effect of bandwidth and the number of training points on the system’s performance. Using NASA’s 42 simulation framework, the experiment determined that in nominal operating scenarios, the actuator input/output relationship is linear. Once enough information is available to capture this linearity, additional training data and differing bandwidths did not significantly affect the system’s performance.

Real-Time Audio-Midi Controller, Brian Shino Balberchak

Computer Engineering

Most MIDI controllers used in music production use a regular keyboard to generate the MIDI notes that are sent to the synthesizer. This project aims to provide the user with a different way of generating MIDI data: by playing an instrument of their choice with a passive electronic pickup to generate MIDI notes that correspond with the fundamental frequency of the musical pitch being played. The pitch-detecting algorithm used in this application utilizes a modified form of auto-correlation.

As an embedded systems project that uses signal-processing techniques, the knowledge of topics from the following courses was essential:

EE 211: Op-Amp …

Development Of A Sprayer Performance Diagnostic Tool Using Improved Mapping And Error Quantification Practices, Aaron Shearer

Department of Agricultural and Biological Systems Engineering: Dissertations, Theses, and Student Research

While sprayer technologies have advanced greatly over the past decade and a half, chemical application errors are still prominent in many in-field operations. Over-application of pesticides can cause harm to the crop, reducing yield, and result in added pollution to the environment. Under-application of pesticides fails to control pests within the field, again lowering crop yields, and causing profit loss for the producer. Current operator feedback from in-field pesticide application operations conveys limited information and often times does not allow the operator to visualize a true representation of their performance. Farm Management Information Systems (FMIS) typically do not account for …

Strategic Audit Of National Instruments, Grant Fishburn

Honors Program: Senior Projects (Public)

The research and analyses compiled in this paper provide a holistic view into the current situation that National Instruments faces as a company and what strategies it can take to overcome current and pressing issues. The goal of the audit is to determine a strategic recommendation for National Instruments that will achieve any number of goals and objectives set by the auditor in accordance to the situation at hand. In addition to this strategic recommendation, an implementation and contingency plan are developed to further expand upon how such a strategy would be created in the real world. The strategic recommendation …

Investigation Of Discrete Element Methods For Stud To Turf Interactions, Justin Rittenhouse

Masters Theses

Artificial turf is frequently used in sports today and attempts to advantageously replicate a natural grass/soil playing surface. Despite numerous advantages, the technology is correlated with an increase in injuries. The concept behind this research is to create and validate a discrete element model (DEM) for the ground/foot interaction through the use of open source software. After validation, the goal is to analyze an arrangement of studs to determine what role stud geometry plays on torque [N-mm] and force [N] generation. The validation data was provided through laboratory experiments. Three football studs attached to a rigid bracket were turned at …

The Impact Of Phosphorous Species On Dewaterability Of Wastewater Solids, Erik Anderson

Master's Theses (2009 -)

Phosphorus regulations are causing Water Resource Recovery Facilities (WRRFs) to implement new technologies to remove phosphorus (P) before they discharge liquid effluent. Enhanced Biological Phosphorus Removal (EBPR) is often employed to remove P from water. However, sludges from EBPR plants have shown decreases in dewaterability soon after EBPR was initiated. This decline in dewaterability is not well understood, nor is the best way to improve the dewatering EBPR sludge. Specifically, the role of different P species on sludge dewaterability is not well understood. Several laboratory experiments were conducted at the Marquette University Water Quality Center with the following objectives: i) …

Hybrid Sensorless Field Oriented And Direct Torque Control For Variable Speed Brushless Dc Motors, Kellen Carey

Master's Theses (2009 -)

The objective of this thesis is to design a hybrid sensorless closed-loop motor controller using a combination of Field-Oriented Control (FOC) and Direct Torque Control (DTC) for brushless DC motors used in multi-rotor aerial vehicles. The primary challenge is the wide range of desired working speeds, which can quickly vary from low speed to high speed. For this range, the control approach must be efficient, effective, and low-cost in order to provide fast response times during initial startup, steady-state, and transient operation. Additional design challenges include minimal response time to desired speed changes and small steady-state speed errors. Finally, the …

Pharmacokinetic Modeling Of 99mtc-Hmpao Images Of Isolated Perfused Rat Lungs, Katherine C. Barry

Master's Theses (2009 -)

The single-photon emission tomography (SPECT) imaging biomarker technetium-labeled hexamethylpropyleneamine oxime (99mTc-HMPAO) exists in two forms, the oxidized, cell-permeable form and the reduced, cell-impermeable form. Recent studies revealed that the lung uptake of 99mTc-HMPAO increases early in rat models of human acute lung injury. Lung uptake of 99mTc-HMPAO is the net result of multiple cellular and vascular processes, many of which can vary with acute illness. Thus, when a change in the lung uptake of 99mTc-HMPAO is detected, it is unclear how much of this change is due to alteration in the activity of the targeted cellular process versus alteration of …

Anaerobic Co-Digestion Of Aqueous Liquid From Biosolids Pyrolysis, Seyedfatemeh Seyedi

Master's Theses (2009 -)

Pyrolysis is a process to treat biosolids and recover energy. During pyrolysis, conversion of organic matter to energy-rich products yields biochar, py-gas, and pyrolysis liquids (aqueous phase and non-aqueous bio-oil). The aqueous pyrolysis liquid (APL), is a high-COD liquid with no apparent use that contains polycyclic aromatic hydrocarbons and nitrogen-containing compounds. One potential beneficial use of APL is as a co-digestate to produce more biogas for renewable energy from anaerobic digesters at municipal water resource recovery facilities. Some of the organics in APL may be converted to biomethane via anaerobic digestion under proper conditions. However, some APL organics are known …

Immersive Visualization In Biomedical Computational Fluid Dynamics And Didactic Teaching And Learning, John Thomas Venn

Master's Theses (2009 -)

Virtual reality (VR) can stimulate active learning, critical thinking, decision making and improved performance. It requires a medium to show virtual content, which is called a virtual environment (VE). The MARquette Visualization Lab (MARVL) is an example of a VE. Robust processes and workflows that allow for the creation of content for use within MARVL further increases the userbase for this valuable resource. A workflow was created to display biomedical computational fluid dynamics (CFD) and complementary data in a wide range of VE’s. This allows a researcher to study the simulation in its natural three-dimensional (3D) morphology. In addition, it …

Effect Of Low Aeration And Heat Drying On Anaerobic Digester Performance And Microbial Community, Dylan Thomas Friss

Master's Theses (2009 -)

This thesis describes three research projects on anaerobic digestion (AD) that investigated functional differences and relationships between microbial composition and digester function. Both archaeal and bacterial communities were characterized using high throughput (Illumina) sequencing technology with universal 16S rRNA gene primers. In the first project, limited aeration, and limited aeration with an aerotolerant enrichment culture were investigated as possible methods to increase digester functional performance in comparison to a strictly anaerobic control digester. No functional differences were observed at quasi-steady state between the limited aerated digester (LAD), limited aerated anaerobic digester augmented with an aerotolerant enrichment culture (LADE), and strictly …

Investigation Of Reactive Oxygen Species Production In The Rat Lung Using Optical Imaging, Nina Friedly

Master's Theses (2009 -)

Oxidative stress, the imbalance between production of oxidants or reactive oxygen species (ROS) and antioxidant activity, plays a key role in the pathogenesis of acute and chronic lung diseases. The objective of this thesis was to develop a robust protocol for measuring the rate of H2O2 production in isolated perfused rat lungs and to determine the cellular sources of that rate using Amplex Red (AR). For a given lung, AR (25 mM) along with horseradish peroxidase (5 U/ml) and ascorbate oxidase (1U/ml) were added to a perfusate reservoir that was recirculated through the lungs and sampled at 5 minute intervals …

Computational Methods For Modeling Multicomponent Droplet Vaporization, Alanna Y. Cooney

Master's Theses (2009 -)

Computational fluid dynamics (CFD) models for combustion of multicomponent hydrocarbon fuels must often prioritize computational efficiency over model complexity, leading to oversimplifying assumptions in the sub-models for droplet vaporization and chemical kinetics. Therefore, a computationally efficient hybrid droplet vaporization-chemical surrogate approach has been developed which emulates both the physical and chemical properties of a multicomponent fuel. For the droplet vaporization/physical portion of the hybrid, a new solution method is presented called the Coupled Algebraic-Direct Quadrature Method of Moments (CA-DQMoM) with delumping which accurately solves for the evolution of every discrete species in a vaporizing multicomponent fuel droplet with the computational …

Uncertainty Aware Mapping Of Embedded Systems For Reliability, Performance, And Energy, Wenkai Guan

Master's Theses (2009 -)

Due to technology downscaling, embedded systems have increased in complexity and heterogeneity. The increasingly large process, voltage, and temperature variations negatively affect the design and optimization process of these systems. These factors contribute to increased uncertainties that in turn undermine the accuracy and effectiveness of traditional design approaches. In this thesis, we formulate the problem of uncertainty aware mapping for multicore embedded system platforms as a multi-objective optimization problem. We present a solution to this problem that integrates uncertainty models as a new design methodology constructed with Monte Carlo and evolutionary algorithms. The solution is uncertainty aware because it is …

Investigation Of The Effects Of Prosthetic Knee Condition On Novice Transfemoral Amputee Runners, Natalie Nelson

Master's Theses (2009 -)

Some unilateral transfemoral amputees (TFAs) run in a prosthesis with an articulating prosthetic knee, others choose to run without a knee (prosthetic socket and foot are linked via a straight, non-articulating pylon) to increase stability. Research regarding unilateral TFA running with an unlocked versus locked prosthetic knee (approximately equivalent to the no-knee condition) with respect to energy cost and temporal metrics is limited; no studies have investigated the impact of knee condition on kinematic metrics. The purpose of this study was to investigate whether the prosthetic knee of a running-specific prosthesis (RSP) should be unlocked or locked for unilateral TFAs …

Using Collapsible Systems To Mitigate Buckling In Thin Flexible Instruments In Robotic Surgery, Brandon Scott Sargent

Theses and Dissertations

Robotic surgery procedures may include long, thin flexible instruments that are inserted by the robot into the patient. As the robot inserts these devices, due to their geometry, they are prone to buckling failure. To mitigate buckling failure, a support system is needed on the robot. This system supports the device but also adapts to the varying ex vivo length of the device as it is inserted. This work presents four collapsible support systems designed to mitigate buckling failure of long, thin instruments while accounting for changing length. The Ori-Guide is an origami-inspired system that has enabled a part reduction …

Large-Scale Strength Testing Of High-Speed Railway Bridge Embankments: Effects Of Cement Treatment And Skew Under Passive Loading, Daniel Ethan Schwicht

Theses and Dissertations

To investigate the passive force-displacement relationships provided by a transitional zoned backfill consisting of cement treated aggregate (CTA) and compacted gravel, a series of full-scale lateral abutment load tests were performed. The transitional zoned backfill was designed to minimize differential settlement adjacent to bridge abutments for the California High Speed Rail project. Tests were performed with a 2-D or plane strain backfill geometry to simulate a wide abutment. To investigate the effect of skew angle on the passive force, lateral abutment load tests were also performed with a simulated abutment with skew angles of 30º and 45º. The peak passive …

Development, Classification And Biomedical Applications Of Nano Composite Piezoresponsive Foam, Aaron Jake Merrell

Theses and Dissertations

This dissertation focuses on the development of and applications for Nano-Composite Piezoresponsive Foam (NCPF). This self-sensing foam sensor technology was discovered through research in a sister technology, High Deflection Strain Gauges (HDSG), and was subsequently developed with some of the same base materials. Both technologies use nano and micro conductive additives to provide electrically responsive properties to materials which otherwise are insulative. NCPF sensors differ from HDSGs in that they provide a dual electrical response to dynamic and static loading, which is measured through an internally generated charge, or a change in resistance. This dissertation focuses on the development of …

Reinforcing Bar Splice Performance In Masonry With Self-Consolidating Grout, Aaron Brent Roper

Theses and Dissertations

The use of self-consolidating grout in reinforced masonry construction provides various advantages such as reduced labor, faster construction, decreased noise pollution and better structural response. This is a relatively new building material however, and little research on self-consolidating grout's structural properties has been conducted. The purpose of this study was to analyze the performance or bond capacity of steel reinforcing bar splices in masonry with self-consolidating grout. Twelve masonry panels approximately 40 in. wide and 32 in. tall consisting of Type S mortar and concrete masonry units grouted with self-consolidating grout and No. 5 steel reinforcing bars were constructed with …

Quantifying Grain Boundary Atomic Structures Using The Smooth Overlap Of Atomic Positions, Jonathan Lake Priedeman

Theses and Dissertations

In this work, the relationship between grain boundary crystallography and grain boundary atomic structure is examined, using [1 0 0] - symmetric tilt grain boundaries in nickel. The structural unit model is used as a benchmark to evaluate the atomic structure description capacities of an emerging structural descriptor, the local environment representation, which itself is a refinement of the also-emergent Smooth Overlap of Atomic Positions (SOAP) descriptor. We show that the local environment representation encodes both the information of the structural unit model and additional information, such as distortion in the structural units and the arrangement of the structural units …

The Estimation Of The Rapidscat Spatial Response Function, Samuel Gary Bury

Theses and Dissertations

RapidScat is a pencil-beam wind scatterometer which operated from September 2014 to August 2016. Mounted aboard the International Space Station (ISS), RapidScat experiences significant altitude and attitude variations over its dataset. These variations need to be properly accounted for to ensure accurate calibration and to produce high resolution scatterometer images. Both the antenna pose and the one-way antenna pattern need to be validated. The spatial response function (SRF) is the two-way antenna pattern for a scatterometer combined with the processing and filtering done in the radar system electronics, and is dominated by the two-way pattern. To verify the pointing of …

Simulation And Experiments To Understand The Manufacturing Process, Microstructure And Transport Properties Of Porous Electrodes, Mohammad Mehdi Forouzan

Theses and Dissertations

Battery technology is a great candidate for energy storage applications. The need for high-performance and cost-effective batteries has motivated researchers to put much effort into improving battery performance. In this work, we attempt to understand the elements that affect the microstructure and performance of two battery systems. The first part of this work focuses on the investigation of transport and structural properties of porous electrodes in an alkaline electrolyte. A DC polarization method was deployed for tortuosity measurements. An apparatus was designed to flow specified current through and measure the voltage drop over the porous electrodes. Using a modified Ohm's …