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Processing Of Advanced Infrared Materials, Daniel Mcgill
Processing Of Advanced Infrared Materials, Daniel Mcgill
Electronic Theses and Dissertations
Infrared transparent glassy and crystalline materials often have unique and complex processing requirements but are an important class of materials for such applications as optical windows, lenses, waveplates, polarizers and beam splitters. This thesis investigates two specific materials, one amorphous and one crystalline, that are candidates for use in the short and midwave-infrared and mid and longwave infrared, respectively. It is demonstrated that an innovative uniaxial sintering process, which uses a sacrificial pressure-transmitting medium, can be used to fully densify a 70TeO2-20WO3-10La2O3 (TWL) glass powder. The characteristics of the sintered TWL glass is compared to that of a parent glass …
Autonomous Robotic Grasping In Unstructured Environments, Amirhossein Jabalameli
Autonomous Robotic Grasping In Unstructured Environments, Amirhossein Jabalameli
Electronic Theses and Dissertations
A crucial problem in robotics is interacting with known or novel objects in unstructured environments. While the convergence of a multitude of research advances is required to address this problem, our goal is to describe a framework that employs the robot's visual perception to identify and execute an appropriate grasp to pick and place novel objects. Analytical approaches explore for solutions through kinematic and dynamic formulations. On the other hand, data-driven methods retrieve grasps according to their prior knowledge of either the target object, human experience, or through information obtained from acquired data. In this dissertation, we propose a framework …
Arterial-Level Real-Time Safety Evaluation In The Context Of Proactive Traffic Management, Jinghui Yuan
Arterial-Level Real-Time Safety Evaluation In The Context Of Proactive Traffic Management, Jinghui Yuan
Electronic Theses and Dissertations
In the context of pro-active traffic management, real-time safety evaluation is one of the most important components. Previous studies on real-time safety analysis mainly focused on freeways, seldom on arterials. With the advancement of sensing technologies and smart city initiative, more and more real-time traffic data sources are available on arterials, which enables us to evaluate the real-time crash risk on arterials. However, there exist substantial differences between arterials and freeways in terms of traffic flow characteristics, data availability, and even crash mechanism. Therefore, this study aims to deeply evaluate the real-time crash risk on arterials from multiple aspects by …
Nanoscale Spectroscopy In Energy And Catalytic Applications, Yi Ding
Nanoscale Spectroscopy In Energy And Catalytic Applications, Yi Ding
Electronic Theses and Dissertations
Emerging societal challenges such as the need for more sustainable energy and catalysis are requiring more sensitive and versatile measurements at the nanoscale. This is the case in the design and optimization of new materials for energy harvesting (solar cells) and energy storage devices (batteries and capacitors), or for the development of new catalysts for carbon sequestration or other reactions of interest. Hence, the ability to advance spectroscopy with nanoscale spatial resolution and high sensitivity holds great promises to meet the demands of deeper fundamental understanding to boost the development and deployment of nano-based devices for real applications. In this …
Investigation Of The Effect Of Edge-Oxidized Graphene Oxide (Eogo) On The Properties Of Cement Composites, Yousef Alharbi
Investigation Of The Effect Of Edge-Oxidized Graphene Oxide (Eogo) On The Properties Of Cement Composites, Yousef Alharbi
Electronic Theses and Dissertations
The use of edge-oxidized graphene oxide (EOGO), produced by a mechanochemical process that allow to deliver a product suitable for large-scale production at affordable cost, as an additive in cement composites was investigated. Comprehensive experimental tests were conducted to investigate the effect of EOGO on the properties of cement composites. The experimental tests were designed for three subtasks: (1) investigation of the performance of EOGO and its mixing method on the strength, pore structure and microstructure of EOGO-cement composites, (2) evaluation of the rheological and fluidity behavior of EOGO-cement paste and mortar, and (3) investigation of the mechanism of the …
Analysis, Design And Efficiency Optimization Of Power Converters For Renewable Energy Applications, Xi Chen
Analysis, Design And Efficiency Optimization Of Power Converters For Renewable Energy Applications, Xi Chen
Electronic Theses and Dissertations
DC-DC power converters are widely used in renewable energy-based power generation systems due to the constant demand of high-power density and high-power conversion efficiency. DC-DC converters can be classified into non-isolated and isolated topologies. For non-isolated topologies, they are typically derived from buck, boost, buck-boost or forth order (such as Cuk, Sepic and Zeta) converters and they usually have relatively higher conversion efficiency than isolated topologies. However, with the applications where the isolation is required, either these topologies should be modified, or alternative topologies are needed. Among various isolated DC-DC converters, the LLC resonant converter is an attractive selection due …
Investigation Of Coastal Vegetation Dynamics And Persistence In Response To Hydrologic And Climatic Events Using Remote Sensing, Subrina Tahsin
Investigation Of Coastal Vegetation Dynamics And Persistence In Response To Hydrologic And Climatic Events Using Remote Sensing, Subrina Tahsin
Electronic Theses and Dissertations
Coastal Wetlands (CW) provide numerous imperative functions and provide an economic base for human societies. Therefore, it is imperative to track and quantify both short and long-term changes in these systems. In this dissertation, CW dynamics related to hydro-meteorological signals were investigated using a series of LANDSAT-derived normalized difference vegetation index (NDVI) data and hydro-meteorological time-series data in Apalachicola Bay, Florida, from 1984 to 2015. NDVI in forested wetlands exhibited more persistence compared to that for scrub and emergent wetlands. NDVI fluctuations generally lagged temperature by approximately three months, and water level by approximately two months. This analysis provided insight …
A Study Of Organo-Phosphorous Simulants Thermal Destruction Using Shock Tube/Laser Diagnostics Techniques And Chemical Kinetics Modeling, Sneha Neupane
Electronic Theses and Dissertations
High-fidelity chemical kinetic models are critical in predictive modeling during design and optimization of next generation energy systems. Shock tube provides an ideal tool to investigate high-temperature chemical kinetics. Non-intrusive laser absorption diagnostics provide in-situ measurements of quantitative, time-resolved species concentration data in this complex chemically reacting system. In this work, shock tube and laser absorption spectroscopy were utilized to measure species concentration time-histories during pyrolysis and oxidation of organo-phosphorous compounds (OPCs). The experiments data obtained were used as benchmark to develop an improved kinetic model of OPCs combustion. Interest in combustion chemistry of OPCs is associated to their use …
Automated Synthesis Of Unconventional Computing Systems, Amad Ul Hassen
Automated Synthesis Of Unconventional Computing Systems, Amad Ul Hassen
Electronic Theses and Dissertations
Despite decades of advancements, modern computing systems which are based on the von Neumann architecture still carry its shortcomings. Moore's law, which had substantially masked the effects of the inherent memory-processor bottleneck of the von Neumann architecture, has slowed down due to transistor dimensions nearing atomic sizes. On the other hand, modern computational requirements, driven by machine learning, pattern recognition, artificial intelligence, data mining, and IoT, are growing at the fastest pace ever. By their inherent nature, these applications are particularly affected by communication-bottlenecks, because processing them requires a large number of simple operations involving data retrieval and storage. The …
Safety, Operational, And Design Analyses Of Managed Toll And Connected Vehicles' Lanes, Moatz Saad
Safety, Operational, And Design Analyses Of Managed Toll And Connected Vehicles' Lanes, Moatz Saad
Electronic Theses and Dissertations
Managed lanes (MLs) have been implemented as a vital strategy for traffic management and traffic safety improvement. The majority of previous studies involving MLs have explored a limited scope of the impact of the MLs segments as a whole, without considering the safety and operational effects of the access design. Also, there are limited studies that investigated the effect of connected vehicles (CVs) on managed lanes. Hence, this study has two main objectives: (1) the first objective is achieved by determining the optimal managed lanes access design, including accessibility level and weaving distance for an at-grade access design. (2) the …
Broadband Mid-Infrared Frequency Combs Generated Via Frequency Division, Qitian Ru
Broadband Mid-Infrared Frequency Combs Generated Via Frequency Division, Qitian Ru
Electronic Theses and Dissertations
Frequency combs have revolutionized metrology and demonstrated numerous applications in science and technology. Combs operating in the mid-infrared region could be beneficial for molecular spectroscopy for several reasons. First, numerous molecules have their spectroscopic signatures in this region. Furthermore, the atmospheric window (3-5μm and 8-14μm) is located here. Additionally, a mid-infrared frequency comb could be employed as a diagnostic tool for the many components of human breath, as well as for detection of harmful gases and contaminants in the atmosphere. In this thesis, I used synchronously pumped subharmonic optical parametric oscillators (OPOs) operating at degeneracy to produce ultra-broadband outputs near …
Analysis Of Residual Stress And Damage Mechanisms Of Thermal Barrier Coatings Deposited Via Ps-Pvd And Eb-Pvd, Linda Rossmann
Analysis Of Residual Stress And Damage Mechanisms Of Thermal Barrier Coatings Deposited Via Ps-Pvd And Eb-Pvd, Linda Rossmann
Electronic Theses and Dissertations
Thermal barrier coatings (TBCs) are critical to gas turbine engines, as they protect the components in the hot section from the extreme temperatures of operation. The current industry standard method of applying TBCs for turbine blades in jet engines is electron-beam physical vapor deposition (EB-PVD), which results in a columnar structure that is valued for its high degree of strain tolerance. An emerging deposition method is plasma-spray physical vapor deposition (PS-PVD), capable of producing a variety of customizable microstructures as well as non-line-of-sight deposition, which allows more complex geometries to be coated, or even multiple parts at once. The pseudo-columnar …
Reconfigurable Reflectarray Antennas With Bandwidth Enhancement For High Gain, Beam-Steering Applications, Michael Trampler
Reconfigurable Reflectarray Antennas With Bandwidth Enhancement For High Gain, Beam-Steering Applications, Michael Trampler
Electronic Theses and Dissertations
Reconfigurable reflectarrays are a class of antennas that combine the advantages of traditional parabolic antennas and phased array antennas. Chapter 1 discusses the basic operational theory of reflectarrays and their design. A review of previous research and the current status is also presented. Furthermore the inherent advantages and disadvantages of the reflectarray topography are presented. In chapter 2, a BST-integrated reflectarray operating at Ka band is presented. Due to the monolithic integration of the tuning element, this design is then extended to V band where a novel interdigital gap configuration is utilized. Finally to overcome loss and phase limitations of …
Mechanical Study On Edge-Oxidized Graphene Oxide (Eogo) Reinforced Concrete, Mohammad Khawaji
Mechanical Study On Edge-Oxidized Graphene Oxide (Eogo) Reinforced Concrete, Mohammad Khawaji
Electronic Theses and Dissertations
It is known that graphene oxide (GO) has superior mechanical properties and can enhance mechanical properties of cement composites. However, Hummer produced conventional GOs have been limited to small-scale specimens (e.g., cement paste and mortar) and applications to concrete have not been implemented due to their high cost and large volume of concrete. Edge-oxidized graphene oxide (EOGO) is a low-cost, carbon-based nanomaterial produced by a mechanochemical process with ball milling and a non-toxic oxidizing agent. The low cost (less than $50/kg) of EOGO enables its use in bulk-scale concrete materials/structures, which is a prerequisite for the field implementation. In this …
A Theoretical, Numerical, And Experimental Study Of Trapped Droplet Coalescence And Mixing, Passively And Under Electric Field, Alireza Karbalaei Baba
A Theoretical, Numerical, And Experimental Study Of Trapped Droplet Coalescence And Mixing, Passively And Under Electric Field, Alireza Karbalaei Baba
Electronic Theses and Dissertations
Passive and electrically active coalescence and mixing of pairs of trapped squeezed nanodroplets were studied in this work. PDMS-glass microfluidic devices were designed and fabricated using multilevel photolithography technique. Flow-focusing method was used to generate nanoliter droplets of died glycerol inside oleic acid. The effect of factors such as flow rates and their ratio, interfacial tension, and viscosities on the size and frequency of droplet generation was studied and concluded by demonstrating the capillary number effect. A passive droplet trapping technique based on minimizing the surface energy of the droplets was employed to minimize the shear flow effects and increase …
A Framework To Develop Anomaly Detection/Fault Isolation Architecture Using System Engineering Principles, Thomas Clark
A Framework To Develop Anomaly Detection/Fault Isolation Architecture Using System Engineering Principles, Thomas Clark
Electronic Theses and Dissertations
For critical systems, timely recognition of an anomalous condition immediately starts the evaluation process. For complex systems, isolating the fault to a component or subsystem results in corrective action sooner so that undesired consequences may be minimized. There are many unique anomaly detection and fault isolation capabilities available with innovative techniques to quickly discover an issue and identify the underlying problems. This research develops a framework to aid in the selection of appropriate anomaly detection and fault isolation technology to augment a given system. To optimize this process, the framework employs a model based systems engineering approach. Specifically, a SysML …
Developing A Traffic Safety Diagnostics System For Unmanned Aerial Vehicles Usingdeep Learning Algorithms, Ou Zheng
Electronic Theses and Dissertations
This thesis presents an automated traffic safety diagnostics solution using deep learning techniques to process traffic videos by Unmanned Aerial Vehicle (UAV). Mask R-CNN is employed to better detect vehicles in UAV videos after video stabilization. The vehicle trajectories are generated when tracking the detected vehicle by Channel and Spatial Reliability Tracking (CSRT) algorithm. During the detection process, missing vehicles could be tracked by the process of identifying stopped vehicles and comparing Intersect of Union (IOU) between the tracking results and the detection results. In addition, rotated bounding rectangles based on the pixel-to- pixel manner masks that are generated by …
A System Dynamics Approach On Sustainability Assessment Of The United States Urban Commuter Transportation, Tolga Ercan
A System Dynamics Approach On Sustainability Assessment Of The United States Urban Commuter Transportation, Tolga Ercan
Electronic Theses and Dissertations
Transportation sector is one of the largest emission sources and is a cause for human health concern due to the high dependency on personal vehicle in the U.S. Transportation mode choice studies are currently limited to micro- and regional-level boundaries, lacking of presenting a complete picture of the issues, and the root causes associated with urban passenger transportation choices in the U.S. Hence, system dynamics modeling approach is utilized to capture complex causal relationships among the critical system parameters affecting alternative transportation mode choices in the U.S. as well as to identify possible policy areas to improve alternative transportation mode …
Development Of Multiport Single Stage Bidirectional Converter For Photovoltaic And Energy Storage Integration, Amit Bhattacharjee
Development Of Multiport Single Stage Bidirectional Converter For Photovoltaic And Energy Storage Integration, Amit Bhattacharjee
Electronic Theses and Dissertations
The energy market is on the verge of a paradigm shift as the emergence of renewable energy sources over traditional fossil fuel based energy supply has started to become cost competitive and viable. Unfortunately, most of the attractive renewable sources come with inherent challenges such as: intermittency and unreliability. This is problematic for today's stable, day ahead market based power system. Fortunately, it is well established that energy storage devices can compensate for renewable sources shortcomings. This makes the integration of energy storage with the renewable energy sources, one of the biggest challenges of modern distributed generation solution. This work …
Ultra-High Performance Concrete For Precast Seismic Bridge Column Connection, Titchenda Chan
Ultra-High Performance Concrete For Precast Seismic Bridge Column Connection, Titchenda Chan
Electronic Theses and Dissertations
Accelerated bridge construction (ABC) utilizes prefabricated bridge elements constructed off-site, delivered, and assembled on-site to expedite construction time and reduce traffic disruption. ABC has been increasingly used for super- and sub-structure elements in low seismic regions. However, its application in medium and high seismic regions remain limited, particularly for precast columns where connections typically coincide with plastic hinge (PH) regions. Ultra-high performance concrete (UHPC), characterized by high compressive and tensile strength, and superior bond properties, is a potential material that can mitigate PH damage and enhance load transfer. This research proposes a new and simple damage tolerant precast column connection …
Development Of Decision Support System For Active Traffic Management Systems Considering Travel Time Reliability, Whoibin Chung
Development Of Decision Support System For Active Traffic Management Systems Considering Travel Time Reliability, Whoibin Chung
Electronic Theses and Dissertations
As traffic problems on roadways have been increasing, active traffic management systems (ATM) using proactive traffic management concept have been deployed on freeways and arterials. The ATM aims to integrate and automate various traffic control strategies such as variable speed limits, queue warning, and ramp metering through a decision support system (DSS). Over the past decade, there have been many efforts to integrate freeways and arterials for the efficient operation of roadway networks. It has been required that these systems should prove their effectiveness in terms of travel time reliability. Therefore, this study aims to develop a new concept of …
Implications Of Groundwater Plume Transport And Analysis Of Karst Aquifer Characteristics In Central Florida, Daljit Sandhu
Implications Of Groundwater Plume Transport And Analysis Of Karst Aquifer Characteristics In Central Florida, Daljit Sandhu
Electronic Theses and Dissertations
Groundwater aquifers make up the primary source of drinking water in Florida. It is imperative to protect and maintain water quality to ensure optimal drinking water conditions. Florida is known for being prone to sinkholes due to karst features. One sinkhole event occurred beneath a phosphogypsum stack, and leaked a large amount of radioactive waste in the Floridan aquifer, raising water quality concerns. To study the behavior of contaminant transport, the radioactive waste plume was modeled by coupling hydraulic and chemistry concepts. Adsorption was studied to see if it can serve as a potential remediation solution to the contaminant waste, …
Holographic Optical Elements For Visible Light Applications In Photo-Thermo-Refractive Glass, Fedor Kompan
Holographic Optical Elements For Visible Light Applications In Photo-Thermo-Refractive Glass, Fedor Kompan
Electronic Theses and Dissertations
This dissertation reports on design and fabrication of various optical elements in Photo-thermo-refractive (PTR) glass. An ability to produce complex holographic optical elements (HOEs) for the visible spectral region appears very beneficial for variety of applications, however, it is limited due to photosensitivity of the glass confined within the UV region. First two parts of this dissertation present two independent approaches to the problem of holographic recording using visible radiation. The first method involves modification of the original PTR glass rendering it photosensitive to radiation in the visible spectral region and, thus, making possible the recording of holograms in PTR …
Investigation Of The Flow Field And Associated Heat Transfer Within An Asymmetrical Leading Edge Jet Impingement Array, Jorge Torres
Investigation Of The Flow Field And Associated Heat Transfer Within An Asymmetrical Leading Edge Jet Impingement Array, Jorge Torres
Electronic Theses and Dissertations
This thesis investigates the turbulent flow features present in asymmetrical leading edge jet impingement and their effects from a fluid and heat transfer prospective using both numerical and experimental techniques. The jet-centerline plane flow field was quantified experimentally through the non-intrusive experimental method of Particle Image Velocimetry (PIV), while an area average heat transfer was acquired via a traditional copper block method. The numerical element served to investigate how well the Reynolds Averaged Navier-Stokes (RANS) k-? SST turbulence model predicts the flow field and heat transfer within the leading edge and further investigate the results outside of the experimental scope. …
Imaging Through Glass-Air Anderson Localizing Optical Fiber, Jian Zhao
Imaging Through Glass-Air Anderson Localizing Optical Fiber, Jian Zhao
Electronic Theses and Dissertations
The fiber-optic imaging system enables imaging deeply into hollow tissue tracts or organs of biological objects in a minimally invasive way, which are inaccessible to conventional microscopy. It is the key technology to visualize biological objects in biomedical research and clinical applications. The fiber-optic imaging system should be able to deliver a high-quality image to resolve the details of cell morphology in vivo and in real time with a miniaturized imaging unit. It also has to be insensitive to environmental perturbations, such as mechanical bending or temperature variations. Besides, both coherent and incoherent light sources should be compatible with the …
Fundamental Properties Of Metallic Nanolasers, William Hayenga
Fundamental Properties Of Metallic Nanolasers, William Hayenga
Electronic Theses and Dissertations
The last two decades have witnessed tremendous advancements in the area of nanophotonics and plasmonics, which has helped propel the development of integrated photonic sources. Of central importance to such circuits is compact, scalable, low threshold, and efficient coherent sources that can be driven at high modulation frequencies. In this regard, metallic nanolasers offer a unique platform. Their introduction has enabled confinement of light at a subwavelength scale and the ultra-small size of the modes afforded by these structures allows for cavity enhancing effects that can help facilitate thresholdless lasing and large direct modulation bandwidths. In this report, I present …
Modeling And Transient Simulation Of A Fully Integrated Multi-Pressure Heat Recovery Steam Generator Using Siemens T3000, Jonathan Mcconnell
Modeling And Transient Simulation Of A Fully Integrated Multi-Pressure Heat Recovery Steam Generator Using Siemens T3000, Jonathan Mcconnell
Electronic Theses and Dissertations
The focus of this research is on the transient thermodynamic properties and dynamic behavior of a Heat Recovery Steam Generator (HRSG). An HRSG is a crossflow heat exchanger designed for the extraction of energy from the hot exhaust gas of a traditional power plant through boiling induced phase change. Superheated steam is sent through a turbine to generate additional power, raising the overall efficiency of a power plant. The addition of renewable energies and the evolution of smart grids have brought forth a necessity to gain a comprehensive understanding of transient behavior within an HRSG in order to efficiently manage …
Frequency-Reconfigurable Microstrip Patch And Cavity-Backed Slot Espars, Wei Ouyang
Frequency-Reconfigurable Microstrip Patch And Cavity-Backed Slot Espars, Wei Ouyang
Electronic Theses and Dissertations
Wireless communication systems have rapidly evolved over the past decade which has led to an explosion of mobile data traffic. Since more and more wireless devices and sensors are being connected, the transition from the current 4G/LTE mobile network to 5G is expected to happen within the next decade. In order to improve signal-to-noise ratio (SNR), system capacity, and link budget, beam steerable antenna arrays are desirable due to their advantage in spatial selectivity and high directivity. Electronically steerable parasitic array radiator (ESPAR) that can achieve low-cost continuously beamsteering using varactor diodes have attracted a lot of attention. This dissertation …
Scalable Map Information Dissemination For Connected And Automated Vehicle Systems, S. M. Osman Gani
Scalable Map Information Dissemination For Connected And Automated Vehicle Systems, S. M. Osman Gani
Electronic Theses and Dissertations
Situational awareness in connected and automated vehicle (CAV) systems becomes particularly challenging in the presence of non-line of sight objects and/or objects beyond the sensing range of local onboard sensors. Despite the fact that fully autonomous driving requires the use of multiple redundant sensor systems, primarily including camera, radar, and LiDAR, the non-line of sight object detection problem still persists due to the inherent limitations of those sensing techniques. To tackle this challenge, the inter-vehicle communication system is envisioned that allows vehicles to exchange self-status updates aiming to extend their effective field of view and thus compensate for the limitations …
A Smart Uav Platform For Railroad Inspection, Ryan Debevec
A Smart Uav Platform For Railroad Inspection, Ryan Debevec
Electronic Theses and Dissertations
Using quadcopters for analysis of an environment has been an intriguing subject of study recently. The purpose of this work is to develop a fully autonomous UAV platform for Railroad inspection The dynamics of the quadrotor is derived using Euler's and Newton's laws and then linearized around the hover position. A PID controller is designed to control the states of the quadrotor in a manner to effectively follow a vision-based path, using the down facing camera on a Parrot Mambo quadrotor. Using computer vision the distance from the position of the quadrotor to the position of the center of the …