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2019

Theses and Dissertations

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Full-Text Articles in Engineering

The Impact Of Patient-Specific Vascular Structure On Localized Cooling In The Human Heart, Nathan Paul Spangenberg Sep 2019

The Impact Of Patient-Specific Vascular Structure On Localized Cooling In The Human Heart, Nathan Paul Spangenberg

Theses and Dissertations

Acute Myocardial Infarction (AMI) is the leading cause of worldwide death and disability, and approximately 720,000 Americans will experience an AMI in 2018. Studies have shown that rapid hypothermia therapy (<35°C) before reperfusion in patients with AMI can reduce infarct size by 37%. Localized therapeutic hypothermia has proven the potential to cool heart tissue rapidly following AMI, 3°C in 5 minutes. Using Materialise Mimics digital imaging software and the finite volume method we analyzed temperature distributions in six patient-specific left main coronary artery (LMCA) models. A mock circulatory loop was used to determine the exiting temperatures of a standard 7 Fr catheter to feed into our model with flow rates ranging from 29.2 ml/min to 68.85 ml/min. Our work showed that therapeutic hypothermia (TH) temperatures were evident at the outlets of three out of all six heart models, which varied in each left anterior descending (LAD) and left circumflex (LCX) artery depending on flowrate. Results of this study indicate that biovariability in patient-specific vascular structures significantly impacts therapeutic hypothermia (TH) treatment methods. These results indicate that further research is needed to examine more accurate physiological effects, such as pulsatile flow and vessel wall thickness. Future models will be used to provide insight to guide more efficient TH device designs and operation parameters to optimize patient outcomes following AMI.


Autonomous And Resilient Management Of All-Source Sensors For Navigation Assurance, Juan D. Jurado Sep 2019

Autonomous And Resilient Management Of All-Source Sensors For Navigation Assurance, Juan D. Jurado

Theses and Dissertations

All-source navigation has become increasingly relevant over the past decade with the development of viable alternative sensor technologies. However, as the number and type of sensors informing a system increases, so does the probability of corrupting the system with sensor modeling errors, signal interference, and undetected faults. Though the latter of these has been extensively researched, the majority of existing approaches have constrained faults to biases, and designed algorithms centered around the assumption of simultaneously redundant, synchronous sensors with valid measurement models, none of which are guaranteed for all-source systems. This research aims to provide all-source multi-sensor resiliency, assurance, and ...


Initial Development Of A Prototype Sensor Testbed For Fetal Monitoring, Christian Beauvais Aug 2019

Initial Development Of A Prototype Sensor Testbed For Fetal Monitoring, Christian Beauvais

Theses and Dissertations

The objective of this research is to design and manufacture a device that exhibits some of the bio-physiological signals relevant to fetal health monitoring. Currently, limited options exist for testing the performance of monitoring devices such as the tocodynamometer (TOCO) and electrocardiograph (ECG) that measure the bio-physiological signals of a woman and her fetus. Sensor designers need ways of generating and acquiring signals that do not carry the ethical burden of human testing. The development of such a device, as considered in this work, may involve using muscle wire or an inflatable tube as prospective foundations for simulating uterine contraction ...


Laboratory Evaluation Of Cold In-Place Recycling Asphalt Mixtures Using A Balanced Mix Design, Ahmed Saidi Aug 2019

Laboratory Evaluation Of Cold In-Place Recycling Asphalt Mixtures Using A Balanced Mix Design, Ahmed Saidi

Theses and Dissertations

The objective of this research study is to present a procedure for designing Cold In-Place Recycling (CIR) mixtures through balancing cracking and rutting for these mixtures. Eight CIR mixtures were prepared using two recycling agents (foamed and emulsified asphalts), then cured for three days at two temperatures (140oF and 50oF), and compacted at two gyration levels (30 and 70 gyrations). The CIR mixtures were prepared at constant dosages of water and cement, 3% and 1%, respectively. Air void of each CIR performance test specimen was determined using the CoreLok device. The rutting susceptibility of these mixtures was then evaluated using ...


Long-Term Performance Of Sustainable Pavements Using Ternary Blended Concrete With Recycled Aggregates, Seth M. Wagner Aug 2019

Long-Term Performance Of Sustainable Pavements Using Ternary Blended Concrete With Recycled Aggregates, Seth M. Wagner

Theses and Dissertations

The purposes of this study were to (a) design concrete pavement mixtures with recycled concrete aggregates using ternary blends of cementitious materials and a low water-to-binder ratio, (b) measure the fresh and hardened properties of the proposed concrete mixtures and (c) assess the long-term performance of the concrete implementing the use of recycled coarse aggregates. Preliminary investigation into ternary blend combinations via the compressive testing of mortar cubes and isothermal calorimetry was used to predict an optimal blend of cementitious material. Mixes using recycled concrete aggregates at varying replacement rates were tested for fresh and hardened properties using the proposed ...


Bioengineering Extracellular Matrix Scaffolds For Volumetric Muscle Loss, Kevin Roberts Aug 2019

Bioengineering Extracellular Matrix Scaffolds For Volumetric Muscle Loss, Kevin Roberts

Theses and Dissertations

Volumetric muscle loss overwhelms skeletal muscle’s ordinarily capable regenerative machinery, resulting in fibrosis and severe functional deficits which have defied clinical repair strategies. My work spans the design and preclinical evaluation of implants intended to drive the cell community of injured muscle toward a regenerative state, as well as the development of an understanding of the molecular responses of this cell community to biomaterial interventions. I demonstrate a new class of biomaterial by leveraging the productive capacity of sacrificial hollow fiber membrane cell culture; I show specifically that unique threads of whole extracellular matrix can be isolated by solvent ...


Investigation Of The Effect Of Age On Regenerative Outcomes Following Treatment Of Volumetric Muscle Loss Injuries, John Taehwan Kim Aug 2019

Investigation Of The Effect Of Age On Regenerative Outcomes Following Treatment Of Volumetric Muscle Loss Injuries, John Taehwan Kim

Theses and Dissertations

Volumetric muscle loss (VML) is a traumatic injury in skeletal muscle resulting in the bulk loss of more than 20% of the muscle’s volume. Included in the bulk loss of muscle is the skeletal muscle niche comprised of nerve bundles, vasculature, local progenitor cells, basal lamina, and muscle fibers, overwhelming innate repair mechanisms. The hallmark of VML injury is the excessive accumulation of non-contractile, fibrotic tissue and permanent functional deficits. Though predominant in the younger demographic, the elderly population is also captured within VML injuries. There are many factors that change with aging in skeletal muscle that may further ...


Five-Level Flying Capacitor Converter Used As A Static Compensator For Current Unbalances In Three-Phase Distribution Systems, Rafael Franceschi Aug 2019

Five-Level Flying Capacitor Converter Used As A Static Compensator For Current Unbalances In Three-Phase Distribution Systems, Rafael Franceschi

Theses and Dissertations

This thesis presents and evaluates a solution for unbalanced current loading in three-phase distribution systems. The proposed solution uses the flying capacitor multilevel converter as its main topology for an application known as Unbalanced Current Static Compensator. The fundamental theory, controller design and prototype construction will be presented along with the experimental results. The Unbalanced Current Static Compensator main objective is the balancing of the up-stream currents from the installation point to eliminate the negative- and zero-sequence currents originated by unbalanced single-phase loads.

Three separate single-phase flying capacitor converters are controlled independently using a d-q rotating reference frame algorithm to ...


Implementation And Analysis Of The Iso/Iec/Ieee P21451-1 Draft Standard For A Smart Transducer Interface Common Network Services And Its Applications In The Internet Of Things, Russell Henry Albert Trafford Jul 2019

Implementation And Analysis Of The Iso/Iec/Ieee P21451-1 Draft Standard For A Smart Transducer Interface Common Network Services And Its Applications In The Internet Of Things, Russell Henry Albert Trafford

Theses and Dissertations

The Internet of Things (IoT) has rapidly become the paradigm for the creation and improvement of new and old Cyber Physical Systems (CPS), but how much longer can this development of IoT devices, networks, and services be sustained? The past decade has seen incredible growth in internet connected devices, with current estimates placing the number of such devices at about 20 billion in 2017, not including personal computers, smart phones, and tablets. This has created a massive market for these devices, with each company making their own applications, protocols, and services. Since these markets are competitive, there originally was no ...


Emotion Recognition Using Facial Feature Extraction, Demiyan Smirnov Jul 2019

Emotion Recognition Using Facial Feature Extraction, Demiyan Smirnov

Theses and Dissertations

Computerized emotion recognition systems can be powerful tools to help solve problems in a wide range of fields including education, healthcare, and marketing. Existing systems use digital images or live video to track facial expressions on a person's face and deduce that person's emotional state. The research presented in this thesis explores combinations of several facial feature extraction techniques with different classifier algorithms. Namely, the feature extraction techniques used in this research were Discrete Cosine/Sine Transforms, Fast Walsh-Hadamard Transform, Principle Component Analysis, and a novel method called XPoint. Features were extracted from both global (using the entire ...


Functional Porous Polydimethlysiloxane As Piezoresistive And Piezoelectric Materials, Taissa Rose Michel Jul 2019

Functional Porous Polydimethlysiloxane As Piezoresistive And Piezoelectric Materials, Taissa Rose Michel

Theses and Dissertations

In this paper, polydimethylsiloxane (PDMS), carbon nanotubes (CNTs), and zinc oxide (ZnO) were combined to create functionalized piezoresistive and piezoelectric sensors for pressure sensing and energy harvesting. Samples were foamed to show that the increased deformability of the foam sensors makes them suitable for a range of applications including dexterous robotics, tactile sensing, energy harvesting, and biosensing. Uniform dispersion of CNTs was achieved with chloroform as the solvent. Samples were foamed using chemical blowing and scaffolding but granulated sugar at 70% porosity resulted in foamed samples with the most consistent mechanical properties. Samples underwent tensile and compressive testing for their ...


Evaluation Of The Cracking Performance Of Geogrid-Reinforced Hot-Mix Asphalt For Airfield Applications, Daniel Offenbacker Jul 2019

Evaluation Of The Cracking Performance Of Geogrid-Reinforced Hot-Mix Asphalt For Airfield Applications, Daniel Offenbacker

Theses and Dissertations

The objective of this study was to evaluate the fatigue cracking performance of geogrid-reinforced Hot-Mix Asphalt (HMA) for use in airfield runways. An airfield HMA mixture with four different geogrid types were selected for this study. The geogrids varied in tensile strength, coating type, opening size, thickness, and fiber material. Several different laboratory performance tests were conducted (Dynamic Complex Modulus, DCM, Overlay Test, OT, and Indirect Tensile Strength, ITS) and the fatigue and/or cracking performance was evaluated. Additionally, different approaches were adopted or developed for the modeling of geogrids in HMA using Finite Element Modeling (FEM). Finally, a Life-Cycle ...


Inverted Cone Convolutional Neural Network For Deboning Mris, Oliver John Palumbo Jun 2019

Inverted Cone Convolutional Neural Network For Deboning Mris, Oliver John Palumbo

Theses and Dissertations

Data plenitude is the power but also the bottleneck for data-driven approaches, including neural networks. In particular, Convolutional Neural Networks (CNNs) require an abundant database of training images to achieve a desired high accuracy. Current techniques employed for boosting small datasets are data augmentation and synthetic data generation, which suffer from computational complexity and imprecision compared to original datasets. In this thesis, we intercalate prior knowledge based on the temporal relation between the images in the third dimension. Specifically, we compute the gradient of subsequent images in the dataset to remove extraneous information and highlight subtle variations between the images ...


Methods For Using Manpower To Assess Usaf Strategic Risk, Calvin J. Bradshaw Iii Jun 2019

Methods For Using Manpower To Assess Usaf Strategic Risk, Calvin J. Bradshaw Iii

Theses and Dissertations

With limited personnel resource funding availability, senior US Air Force (USAF) decision makers struggle to base enterprise resource allocation from rigorous analytical traceability. There are over 240 career fields in the USAF spanning 12 enterprises. Each enterprise develops annual risk assessments by distinctive core capabilities. A core capability (e.g. Research and Development) is an enabling function necessary for the USAF to perform its mission as part of the Department of Defense (DOD). Assessing risk at the core capability is a good start to assessing risk, but is still not comprehensiveness enough. One of the twelve enterprises has linked its ...


Applying Internet Of Things Principles To Spacecraft, Brian K. Dixon May 2019

Applying Internet Of Things Principles To Spacecraft, Brian K. Dixon

Theses and Dissertations

This thesis proposes the adaptation of the IEEE 1451 Transducer Electronic Data Sheet (TEDS) for usage in spacecraft subsystems. In the 1990s, TEDS initially were developed as a standardized method to provide metadata required for the operation of a transducer by a microcontroller or data acquisition device. The metadata provides information that identifies and documents key characteristics of the transducer, thereby facilitating plug-and-play interoperability within a system and across networks. An overarching goal of this thesis is to make a case for adapting and extending the TEDS concept as a means for self-describing critical physical components of a CubeSat nanosatellite ...


Fabrication Of Enhanced Carbon Based Biocompatible And Biodegradable Microelectronic Materials Derived From Lignocellulosic Biomass, Harrison Thomas Hawkins May 2019

Fabrication Of Enhanced Carbon Based Biocompatible And Biodegradable Microelectronic Materials Derived From Lignocellulosic Biomass, Harrison Thomas Hawkins

Theses and Dissertations

The development of materials capable of harmlessly being broken down and removed from the body is a crucial step towards the development of short-term application electronic biomedical implants. Once developed, these implants, known as bioresorbable electronics, will open a wide array of temporary applications in the field of biomedical implantable devices. Necessary to the operation of bioresorbable electronics within the body is a power source that is similarly biocompatible and biodegradable. To this end, enhanced carbon-based materials and a bio-ionic liquid were developed for the fabrication of a preliminary implantable and bioresorbable battery and tested for functional properties. Electrodes were ...


Feedforward And Feedback Signals In The Olfactory System, Srimoy Chakraborty May 2019

Feedforward And Feedback Signals In The Olfactory System, Srimoy Chakraborty

Theses and Dissertations

The conglomeration of myriad activities in neural systems often results in prominent oscillations. The primary goal of the research presented in this thesis was to study effects of sensory stimulus on the olfactory system of rats, focusing on the olfactory bulb (OB) and the anterior piriform cortex (aPC). Extracellular electrophysiological measurements revealed distinct frequency bands of oscillations in OB and aPC. However, how these oscillatory fluctuations help the animal to process sensory input is not clearly understood. Here we show high frequency oscillations in olfactory bulb carry feedforward signals to anterior piriform cortex whereas feedback from the aPC is predominantly ...


Predicting The Mechanical Properties Of Nanocomposites Reinforced With 1-D, 2-D And 3-D Nanomaterials, Scott Edward Muller May 2019

Predicting The Mechanical Properties Of Nanocomposites Reinforced With 1-D, 2-D And 3-D Nanomaterials, Scott Edward Muller

Theses and Dissertations

Materials with features at the nanoscale can provide unique mechanical properties and increased functionality when included as part of a nanocomposite. This dissertation utilizes computational methods at multiple scales, including molecular dynamics (MD) and density functional theory (DFT), and the coupled atomistic and discrete dislocation multiscale method (CADD), to predict the mechanical properties of nanocomposites possessing nanomaterials that are either 1-D (carbyne chains), 2-D (graphene sheets), or 3-D (Al/amorphous-Si core-shell nanorod).

The MD method is used to model Ni-graphene nanocomposites. The strength of a Ni-graphene nanocomposite is found to improve by increasing the gap between the graphene sheet and ...


Fault Adaptive Workload Allocation For Complex Manufacturing Systems, Charlie B. Destefano May 2019

Fault Adaptive Workload Allocation For Complex Manufacturing Systems, Charlie B. Destefano

Theses and Dissertations

This research proposes novel fault adaptive workload allocation (FAWA) strategies for the health management of complex manufacturing systems. The primary goal of these strategies is to minimize maintenance costs and maximize production by strategically controlling when and where failures occur through condition-based workload allocation.

For complex systems that are capable of performing tasks a variety of different ways, such as an industrial robot arm that can move between locations using different joint angle configurations and path trajectories, each option, i.e. mission plan, will result in different degradation rates and life-expectancies. Consequently, this can make it difficult to predict when ...


Hardware Ip Classification Through Weighted Characteristics, Brendan Mcgeehan May 2019

Hardware Ip Classification Through Weighted Characteristics, Brendan Mcgeehan

Theses and Dissertations

Today’s business model for hardware designs frequently incorporates third-party Intellectual Property (IP) due to the many benefits it can bring to a company. For instance, outsourcing certain components of an overall design can reduce time-to-market by allowing each party to specialize and perfect a specific part of the overall design. However, allowing third-party involvement also increases the possibility of malicious attacks, such as hardware Trojan insertion. Trojan insertion is a particularly dangerous security threat because testing the functionality of an IP can often leave the Trojan undetected. Therefore, this thesis work provides an improvement on a Trojan detection method ...


Asynchronous Circuit Synthesis Using Multi-Threshold Null Convention Logic, Nicholas Renoudet Mize May 2019

Asynchronous Circuit Synthesis Using Multi-Threshold Null Convention Logic, Nicholas Renoudet Mize

Theses and Dissertations

As the demand for an energy-efficient alternative to traditional synchronous circuit design grows, hardware designers must reconsider the traditional clock tree. By doing away with the constrains of a clock, asynchronous sequential circuit designs can achieve a much greater level of efficiency. The utilization of asynchronous logic synthesis flows has enabled researchers to better implement asynchronous circuit designs which have been optimized using the same industry standard tools that are already used in sequential synchronous designs. This thesis offers a new flow for such tools which implements the MTNCL asynchronous circuit architecture.


Towards A Prototype Platform For Ros Integrations On A Ground Robot, Taylor Joseph Linville Whitaker May 2019

Towards A Prototype Platform For Ros Integrations On A Ground Robot, Taylor Joseph Linville Whitaker

Theses and Dissertations

The intent of this work was to develop, evaluate, and demonstrate a prototype robot platform on which ROS integrations could be explored. With observations of features and requirements of existing industrial and service mobile ground robots, a platform was designed and outfitted with appropriate components to enable the most common operational-critical functionalities and account for unforeseen components and features. The resulting Arlo Demonstration Robot accommodates basic mapping, localization, and navigation in both two and three-dimensional space as well as additional safety and teleoperation features. The control system is centered around the Zybo Z7 FPGA SoC hosting a custom hardware design ...


Plasmonic Properties Of Nanoparticle And Two Dimensional Material Integrated Structure, Desalegn Tadesse Debu May 2019

Plasmonic Properties Of Nanoparticle And Two Dimensional Material Integrated Structure, Desalegn Tadesse Debu

Theses and Dissertations

Recently, various groups have demonstrated nano-scale engineering of nanostructures for optical to infrared wavelength plasmonic applications. Most fabrication technique processes, especially those using noble metals, requires an adhesion layer. Previously proposed theoretical work to support experimental measurement often neglect the effect of the adhesion layers. The first finding of this work focuses on the impact of the adhesion layer on nanoparticle plasmonic properties. Gold nanodisks with a titanium adhesion layer are investigated by calculating the scattering, absorption, and extinction cross-section with numerical simulations using a finite difference time domain (FDTD) method. I demonstrate that a gold nanodisk with an adhesive ...


The Effective Use Of Portland Cement In Reactive Powder Hybrid Asphalt Concrete, Clayton Cloutier May 2019

The Effective Use Of Portland Cement In Reactive Powder Hybrid Asphalt Concrete, Clayton Cloutier

Theses and Dissertations

Today, building a durable and cost-efficient infrastructure while minimizing future repair needs is a challenging task, and innovative technological breakthroughs are needed. Limited research has been conducted to investigate the use of portland cement (PC) to improve the performance of asphalt pavements. Portland cement in bitumen materials is attractive as it can improve the performance and reduce costs. Warm Mix Asphalt (WMA) is also an attractive alternative to Hot Mix Asphalt (HMA) as this material produces tremendous energy savings by lowering the production temperatures and enhances certain performance characteristics. It can be envisioned that the use of portland cement incorporated ...


Derivation Of Power System Module Metamodels For Early Shipboard Design Explorations, Rounak Siddaiah May 2019

Derivation Of Power System Module Metamodels For Early Shipboard Design Explorations, Rounak Siddaiah

Theses and Dissertations

The U.S. Navy is currently challenged to develop new ship designs under compressed schedules.

These ship designs must necessarily incorporate emerging technologies for high power energy

conversion in order to enable smaller ship designs with a high degree of electrification and

next generation electrified weapons. One way this challenge is being addressed is through development

of collaborative concurrent design environment that allows for design space exploration

across a wide range of implementation options. The most significant challenge is assurance of

a dependable power and energy service via the shipboard Integrated Power and Energy System

(IPES). The IPES is largely ...


Identifying And Incorporating Driver Behavior Variables Into Crash Prediction Models, Mohammad Razaur Rahman Shaon May 2019

Identifying And Incorporating Driver Behavior Variables Into Crash Prediction Models, Mohammad Razaur Rahman Shaon

Theses and Dissertations

All travelers are exposed to the risk for crashes on the road, as none of the roadways are entirely safe. Under Vision Zero, improving traffic safety on our nation’s highways is and will continue to be one of the most pivotal tasks on the national transportation agenda. For decades, researchers and transportation professionals have strived to identify causal relationships between crash occurrence and roadway geometry, and traffic-related variables on the mission of creating a safe environment for the traveling public. Although great achievements have been witnessed such as the publication of the Highway Safety Manual (HSM), research is rather ...


Quantitative Evaluation Of Geared Manual Wheelchair Mobility In Individuals With Spinal Cord Injury: An Integrative Approach, Omid Jahanian May 2019

Quantitative Evaluation Of Geared Manual Wheelchair Mobility In Individuals With Spinal Cord Injury: An Integrative Approach, Omid Jahanian

Theses and Dissertations

The purpose of this dissertation is to quantify the effects of using geared wheelchair wheels on upper extremity biomechanics and energy expenditure during functional mobility tasks in individuals with spinal cord injury (SCI). The effects of using geared wheels on hand-rim biomechanics, glenohumeral joint dynamics, and shoulder muscle activity were investigated during manual wheelchair propulsion over tiled and carpeted level-floors and up a ramp in low gear (1.5:1) and standard gear (1:1) conditions. The results for the hand-rim biomechanics indicated that regardless of the terrain, using the geared wheels in the low gear condition significantly decreased the ...


A Viable Residential Dc Microgrid For Low Income Communities – Architecture, Protection And Education, Karthik Palaniappan May 2019

A Viable Residential Dc Microgrid For Low Income Communities – Architecture, Protection And Education, Karthik Palaniappan

Theses and Dissertations

The availability of fossil fuels in the future and the environmental effects such as the carbon footprint of the existing methodologies to produce electricity is an increasing area of concern. In rural areas of under-developed parts of the world, the problem is lack of access to electrification. DC microgrids have become a proven solution to electrification in these areas with demonstrated exceptional quality of power, high reliability, efficiency, and simplified integration between renewable energy sources (principally solar PV) and energy storage. In the United States, a different problem occurs that can be addressed with the same DC microgrid approach that ...


A Comprehensive Study On The Estimation Of Freeway Travel Time Index And The Effect Of Traffic Data Quality, Ambily Pankaj May 2019

A Comprehensive Study On The Estimation Of Freeway Travel Time Index And The Effect Of Traffic Data Quality, Ambily Pankaj

Theses and Dissertations

Travel time reliability aims to quantify the variation of travel time by using the entire range of travel times for a given trip, for a selected time period over a selected horizon. A trip can occur over a segment, facility or any subset of the transportation network, for the purpose of calculating travel time reliability. As one of the most important performance measures, travel time reliability reports the number of trips that fail or succeed according to a predetermined standard. Unreliability is usually caused by the interaction of factors that influence travel times, such as fluctuations in demand due to ...


Structural Health Monitoring Of Laminate Structures Using Shear-Mode Piezoelectric Sensors, Hussain Altammar May 2019

Structural Health Monitoring Of Laminate Structures Using Shear-Mode Piezoelectric Sensors, Hussain Altammar

Theses and Dissertations

Structural health monitoring (SHM) employing embedded piezoelectric transducers has shown potential as a promising solution for inspection of different engineering structures such as aircraft, bridges, and renewable energy structures. Despite advancements in the field of ultrasonic SHM, inspection of laminate structures is still a major challenge due to their susceptibility to various joint defects. This thesis presents a novel approach to tackle the challenge of inspecting laminate structures using shear-mode (d35) piezoelectric transducers that are made of lead zirconate titanate (PZT).

This study begins with the characterization of d35 piezoelectric transducers using analytical, numerical, and experimental approaches. The results were ...