Engineering Commons^™

Adaptive Transmission Protocols For Wireless Communication Systems With Fountain Coding, Jason Ellis

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We present low-complexity adaptive protocols for both unicast and multicast transmission in wireless communication systems that employ higher layer fountain codes. Our adaptive protocols respond to variations in channel conditions by adapting the modulation and channel coding of transmitted packets, and they provide efficient communication over wireless channels that experience fading, shadowing, and other time-varying propagation losses. The operation of our protocols is governed by simple receiver statistics that can be obtained during the demodulation of received packets. We present three adaptive protocols for fountain-coded unicast transmission, and compare the throughput performance of our protocols with that of fixed-rate systems, …

Design And Synthesis Of Polymer - Magnetic Nanoparticle Composites For Use In Biomedical Applications, Roland Stone

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The future of diagnostics and therapeutic drugs in biomedicine is nanoparticles. These nanoparticles come in many different shapes, sizes, and combination of materials. Magnetic nanoparticles have been studied for many years for use in biomedicine, not only for their high surface area, but also because of its unique magnetic properties. They can magnetically interact with their environment, be guided to a specific location, and manipulated to release energy in the form of heat. To ensure that these magnetic nanoparticles survive in the circulatory system, they must be modified with materials to make them colloidally stable in water and shield them …

Hybrid Low-Order Modeling For Conceptual Vehicle Design, Robert Mau

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Design freedom, and particularly the freedom to incorporate innovative designs and strategies, is greatest at the very beginning of vehicle conceptual design. Conversely, this is when the least knowledge of the product exists. As product content decisions are made the level of freedom in the design decreases and the design becomes "locked in." The majority of vehicle lifecycle cost is also set by the end of vehicle conceptual design. This makes it critical to make well-informed and validated decisions in the concept design phase to avoid expensive iterations and redesign in the detailed design phase. Parametric vehicle modeling permits rapid …

Enhancing Energy Efficiency In Connected Vehicles Via Access To Traffic Signal Information, Grant Mahler

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This dissertation expounds on algorithms that can deterministically or proba-bilistically predict the future Signal Phase and Timing (SPAT) of a traffic signal by relying on real-time information from numerous vehicles and traffic infrastructure, historical data, and the computational power of a back-end computing cluster. When made available on an open server, predictive information about traffic signals’ states can be extremely valuable in enabling new fuel efficiency and safety functionalities in connected vehicles: Predictive Cruise Control (PCC) can use the predicted timing plan to calculate globally optimal velocity trajectories that reduce idling time at red signals and therefore improve fuel efficiency …

A Hybrid Method Of Performing Electric Power System Fault Ride-Through Evaluations On Medium Voltage Multi-Megawatt Devices, John Fox

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This dissertation explores the design and analysis of a Hybrid Method of performing electrical power system fault ride-through evaluations on multi-megawatt, medium voltage power conversion equipment. Fault ride-through evaluations on such equipment are needed in order to verify and validate full scale designs prior to being implemented in the field. Ultimately, these evaluations will help in reducing the deployment risks associated with bringing new technologies into the marketplace. This is especially true for renewable energy and utility scale energy storage systems, where a significant amount of attention in recent years has focused on their ever increasing role in power system …

Assessment Of The Human Factors Analysis And Classification System (Hfacs): Intra-Rater And Inter-Rater Reliability, Awatef Ergai

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Human error has been identified as the primary contributing cause for up to 80% of the accidents in complex, high risk systems such as aviation, oil and gas, mining and healthcare. Many models have been proposed to analyze these incidents and identify their causes, focusing on the human factor. One such safety model is the Human Factors Analysis and Classification System (HFACS), a comprehensive accident investigation and analysis tool which focuses not only on the act of the individual preceding the accident but on other contributing factors in the system as well. Since its development, HFACS has received substantial research …

Effect Of Graphitic Carbon Nanomodifiers On The Electromagnetic Shielding Effectiveness Of Linear Low Density Polyethylene Nanocomposites, Byron Villacorta Hernandez

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Conductive polymer composites have become alternative materials for providing electromagnetic and electrostatic shielding where metals are not suitable. In this study, the effect of crystallinity, morphology, concentration and orientation of carbon nanomodifiers on shielding provided by their polyethylene-based composites has been investigated relative to their transport properties.

First, the electrical properties and EM SE of composites consisting of heat-treated carbon nanofibers (Pyrograf^® -III PR-19 CNF) in a linear low density polyethylene (LLDPE) matrix were assessed. Heat treatment (HT) of CNF at 2500°C significantly improved their graphitic crystallinity and intrinsic transport properties, thereby increasing the EM SE of the nanocomposites. …

Sulfonated Perfluorocyclobutyl (Pfcb) Aryl Ether Polymers: Synthesis, Reactivity, And Characterization For Polymer Electrolyte Applications, Jiyoung Park

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Perfluorocyclobutyl (PFCB) aryl ether copolymers are excellent candidates for proton exchange membrane (PEM) component in PEM fuel cells. Sulfonated PFCB copolymer membranes exhibit not only high chemical/thermal/mechanical stability but also high proton conductivity. In this regard, PFCB aryl ether copolymers were synthesized via thermal step-growth [2 + 2] cyclopolymerization from aryl bis-(trifluorovinyl ether) (TFVE) monomers and oligomers. Experimental and computational studies confirmed that copolymerization of relatively electron-rich and electron-poor TFVE monomers gave selective-segmented copolymers in an one-pot polymerization. After sulfonation, the PFCB copolymers comprising hydrophilic and hydrophobic segments gave membranes with high proton conductivity. Cross-linked membranes of the sulfonated PFCB …

Vascular Nanomedicine: Site Specific Delivery Of Elastin Stabilizing Therapeutics To Damaged Arteries, Aditi Sinha

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Elastin, a structural protein in the extra-cellular matrix, plays a critical role in the normal functioning of blood vessels. Apart from performing its primary function of providing resilience to arteries, it also plays major role in regulating cell-cell and cell-matrix interactions, response to injury, and morphogenesis. Medial arterial calcification (MAC) and abdominal aortic aneurysm (AAA) are two diseases where the structural and functional integrity of elastin is severely compromised. Although the clinical presentation of MAC and AAA differ, they have one common underlying causative mechanism--pathological degradation of elastin. Hence prevention of elastin degradation in the early stages of MAC and …

Encapsulated And Monolithic Resonant Structures For Laser Applications, Aaron Pung

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Typically, the composition of a laser system includes a gain medium, a pump illumination source, and an external feedback cavity. This cavity consists of a highly reflective mirror and an outcoupler component. The geometry of the outcoupler can be engineered to tailor the reflected or transmitted beam's spatial and spectral distribution. Functionally, the transmitted beam profile is dependent on the laser application. Broadband reflection profiles can be obtained by utilizing a distributed Bragg reflector (DBR). A DBR device consists of multiple layers of alternating materials. Constructive interference of the reflected light off each interface between different materials produces the spectrally …

Optimal Retrofit Strategy Design For Highway Bridges Under Seismic Hazards: A Case Study Of Charleston, Sc, Shawn Parmelee

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A significant number of US highway bridges are inadequate for seismic loads and could be seriously damaged or collapse during a relatively small earthquake. On the most recent infrastructure report card from the American Society of Civil Engineers (ASCE), one-third of the bridges in the United States are deemed to be structurally deficient. To improve this situation, at-risk bridges must be identified, evaluated, and effective retrofitting programs implemented to reduce their seismic vulnerabilities. In practice, the Federal Highway Administration uses the expected damage method and indices method to assess the condition of bridges. These methods compare the severity of expected …

Effects Of Iteration On Concept Development, Shivraj Ranganathan

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Iteration in the conceptual design stage is defined as repetition of design tasks to incorporate new information. A more concise definition of iteration relevant to this research would be the progression of design through different abstraction levels or design stages, defining and refining design solutions while progressing from initial concepts to a more detailed design. Although it is believed that iteration has a positive effect on the quality of ideas in the design process, this experimental study presents an opportunity to determine the effects of iteration on quality of concepts and the factors that lead to increased quality of concepts. …

Development And Verification Of A Test System To Quantify Strain Of An Optical Displacement Indicator And The Design Of A Strain Indicating Prototype, Josh Lake

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The organic-rich Middle Devonian Marcellus Shale of the Appalachian basin is a rapidly developing natural gas play. Stratigraphic boundaries of the Marcellus Shale in Westmoreland County, Pennsylvania were identified using geophysical logs from 10 vertical gas-producing wells in a 23 sq. km area. Gamma-ray, bulk density, and resistivity well logs were examined to assess hydrocarbon potential. Values of porosity, total organic carbon (TOC), and water saturation (SW) were derived and mapped by incorporating well-log data into Marcellus-specific formulas. Gamma-ray, penetration (minutes per foot drilled), and mud-logging gas (total gas) from 12 horizontal wells from within the study area were also …

Dissolved Carbon Dioxide For Scale Removal In Reverse Osmosis, Erin Partlan

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Membrane fouling is a major operational issue in reverse osmosis (RO) desalination plants. In particular, plants treating brackish groundwater can encounter troublesome inorganic scales, including carbonates, sulfates, and silicates. A novel cleaning method is proposed to remove inorganic scales from fouled RO membranes usinag dissolved CO ₂ . As CO₂ molecules encounter membrane foulants, the surfaces serve as nucleation sites for small bubbles to form and shear off foulants. Dissolved CO₂ solutions were prepared by bubbling CO₂ gas into water held in a pressure vessel. Gas dissolution was confirmed by enhanced exit velocities for water containing CO …

Design Of An Optical Position Sensor For Microfiber Actuators, Luxi Cheng

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This thesis introduces a new type of sensor that detects the position information of a paramagnetic microfiber and transforms it to computational electrical signal. The original purpose of the sensor is to solve the problem of feedback signal detection of the microfiber control system, which is the problem of detecting the position information for the microfiber. The microfiber will be presented as the experimental object of this sensor to test its capability. A novel optical based approach is used to transfer the position signal to a computer scrutable signal for further analysis.

The purpose of the sensor design comes from …

Interstitial Cell Seeding And Dynamic Conditioning Of Aortic Heart Valve Scaffolds, Allison Kennamer

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In 2011, U.S. Markets for Heart Valve Repair and Replacement Products estimated that roughly four million people in the United States are diagnosed with a heart valve disorder annually. And in the following year, the American Heart Association reported that approximately 35,000 deaths in the US were either directly or indirectly attributed to heart valve disease. Diseases of the heart valve are degenerative in nature and therefore progressively worsen unbeknownst to the patient until symptoms become clinically relevant. By this time, the valve is in such poor condition that complete replacement is often the only effective treatment. Current solutions are …

Analyzing Requirement Type Influence On Generated Solutions, Emily Worinkeng

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Several ideation methods are available and used by engineering designers to enable the generation of alternative designs [1]. However, there has been little work done to understand the role that the design problem given to participants plays in the ideation process. The contribution of this research is found through the proposed guidelines with respect to the type of requirements to include as part of the design problem in order to achieve the desired quantity, quality, novelty, and variety of solutions during the early stages of the design process. This work is the first attempt at analyzing the effect of requirement …

A Study Of Gallery Method To Increase Idea Quality In Conceptual Design, Liz Mathew

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The objective of this research is to evaluate whether gallery method increases idea quality in conceptual design for engineering design problems. The gallery method is a group ideation process which allows individuals to first generate ideas individually, followed by pooling of ideas to conduct group ideation. Design engineers are often encouraged to work in groups to generate concepts and solutions for design problems. However, past research argues that individual ideation results in higher quality design concepts compared to the group ideation methods. The limitations of group ideation such as free riding, production blocking, evaluation apprehension, and goal incongruity are identified …

The Effects Of Different Size Gold Nanoparticles On Mechanical Properties Of Vascular Smooth Muscle Cells Under Mechanical Stretching, Tri Kieu

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The field of nanotechnology research has seen a large growth in the past few decades due to the great potential of novel nano-size material for useful applications such as drug delivery and medical imaging. Also, they are a promising platform for the detection of terrible diseases such as cancer and atherosclerosis. Although these materials hold great promise, there is very limited understanding about the biological effects of these nanoparticles on normal healthy cells, such as vascular smooth muscle cells (VSMCs). The VSMCs are unique cells due to the two distinct phenotype characteristics it can express: a contractile and a synthetic …

Chemical, Physical, And Moisture Release Characteristics Of Compost Based Potting Media, Tianzhen Wang

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A commercially available composted cow manure was used as a potting media amendment. A common base mix for woody ornamentals of 8 parts pine bark and 1 part sand was compared with 3 other mixes that contained 20%, 30%, and 40% compost (v/v). The remaining fraction of these three mixes was the base mix (bark and sand). Samples of the pine bark and compost were analyzed to determine the following plant nutrients and mineral concentrations: nitrogen (organic and soluble), carbon, P2O5, K2O, Ca, S, Mg, Mn, Cu, Zn, Na, Fe, and Al.

Knowledge Base Representation With Axiomatic Design Rules For Concept Level Up Implement In Ontological Framework, Zhuochen Shi

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Axiomatic Design has been applied and developed as a tool, offering a scientific basis for design and improving design activities. Axiomatic Design has been used in various fields such as software system design, structure design, and product design. However, several challenges and limitations exist in Axiomatic Design including: the inconsistency in identifying design parameters, existence of coupled design, and multiple groups of functional requirements and design parameters. Aimed at using Axiomatic Design to generate conceptual solutions in engineering design while overcoming its limitations, a formal ontology is developed. The ontology defines functional requirements, design parameters, concepts, components and variables and …

Cost And Embodied Energy Optimization Of Rectangular Reinforced Concrete Beams, Alexander Kosloski

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Concrete has a large environmental footprint so it is desirable to find ways to efficiently design structural members. Engineers can exercise their abilities early on in the design phase of construction projects to reduce the environmental footprint by minimizing the amount of materials required. One way to achieve these results is to optimize the design of structural concrete. In this study, simple-span rectangular reinforced concrete (RC) beams with a range of different bending moments were analyzed. The primary goal was to combine life cycle analysis (LCA), numerical optimization, and reinforced concrete mechanics to create a framework for designing efficient RC …

Adaptive Transmission For Ofdm, Michael Juang

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To respond to dynamic channel conditions caused by fading, shadowing, and other time-varying disturbances, orthogonal frequency division multiplexing (OFDM) packet radio systems should adapt transmission parameters on a packet-by-packet basis to maintain or improve performance over the channel. For this to be possible, there are three key ideas that must be addressed: first, how to determine the subchannel conditions; second, which transmission parameters should be adapted; and third, how to adapt those parameters intelligently. In this thesis, we propose a procedure for determining relative subchannel quality without using any traditional channel measurements. Instead, statistics derived solely from subcarrier error counts …

Phonon Transport Analysis Of Semiconductor Nanocomposites Using Monte Carlo Simulations, Mayank Malladi

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Nanocomposites are composite materials which incorporate nanosized particles, platelets or fibers. The addition of nanosized phases into the bulk matrix can lead to significantly different material properties compared to their macrocomposite counterparts. For nanocomposites, thermal conductivity is one of the most important physical properties. Manipulation and control of thermal conductivity in nanocomposites have impacted a variety of applications. In particular, it has been shown that the phonon thermal conductivity can be reduced significantly in nanocomposites due to the increase in phonon interface scattering while the electrical conductivity can be maintained. This extraordinary property of nanocomposites has been used to enhance …

Mechanistic Characterization Of Rubberized Asphalt Mixture And Design Using Full Scale Tire-Pavement Finite Element Modeling, Sajib Saha

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Rubberized half-warm mix asphalt (HWMA) is being considered as one of the promising and sustainable solutions to the current environmental and economic crisis of asphalt industry. A fully mechanistic characterization and performance analysis of this mixture subjected to realistic loading and temperature conditions is necessary before its application in a practical pavement structure. The objective of this research is to characterize the viscoelastic properties of rubberized HWMA at different temperatures and to develop and validate a finite element model of a tire-pavement structure. In this research, a generalized Maxwell model is chosen to represent the time dependent stress-strain behavior of …

Development And Testing Of An Impact Plate Yield Monitor For Peanuts, Jacob Fravel

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Advancements in precision agriculture technologies such as yield monitors have allowed for improved management capabilities and reduced input costs for a number of crops. Most commercialized developments in yield monitoring systems and technologies to date have been directed for use with the major grain crops such as corn, soybeans and cereal grains. This research focuses on development and testing of an impact plate yield monitor system for the peanut harvest. Using a four row peanut combine in virginia type peanuts, 4.8 ha (12 ac) of simultaneous yield data were recorded from an Ag Leader® grain (impact plate) yield monitor and …

Bite Detection And Differentiation Using Templates Of Wrist Motion, Soheila Eskandari

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We introduce a new algorithm of bite detection during an eating activity based on template matching. The algorithm uses a template to model the motion of the wrist over a 6-second window centered on the time when a person takes a bite. We also determine if different types of bites (for example food vs. drink, or using different types of utensils) have different wrist motion templates. This method is implemented on 22,383 bites and 5 different types of templates are built. We then describe a method to recognize different types of bites using the set of templates. The obtained accuracy …

An Exploratory Study On The Effects Of Goal Alignment, Interventions, And Motivational Factors On Innovative Engineering Design Projects, Blake Linnerud

All Theses

Innovation has become an important facet of engineering design, both in industry and the academy. Many senior-level engineering design courses encourage students to develop innovative solutions to open design projects from industry sponsors. Like industry, these academic problems are tackled by teams of students. Student teams that function at the highest level are more likely to reach the innovative solutions for which they are searching. The research presented in this work focuses on two main areas: (1) understanding what motivates engineers when working on innovative design projects and (2) determining the effects of goal alignment interventions on design teams working …

A Probabilistic Analysis Of Islanding Effects In A Modeled Distribution System With Renewable Resources, Paul Gooding

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For this research, an investigation was undertaken regarding the inclusion of renewable resources into the distribution system. This incorporated the increasing prevalence of solar and wind resources, as well as the development of islanding capabilities within distribution systems.

Safety And Operational Characteristics Of Lane Widths On Urban And Rural Roadways A Simulator Study, Meredith Ladue

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The primary goal for this study was to further evaluate and assess the effect of lane width on the safety and operation of roadways in South Carolina. Due to various site conditions that affect the safety and operations of roadways, highway design engineers often face many challenges when developing appropriate road design standards. To investigate specific site conditions for the South Carolina Department of Transportation (SCDOT) a research study took place. In 2011, Part 1 of this research included field studies conducted by Kevin Baumann and Trey Jordan. Due to the various limitations of the field studies it was evident …