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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 …
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 …
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 …
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 …
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 …
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 …
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 …
Lithium Polysulfide Battery With Improved Capacity And Cycle Performance Using Carbon Black Coated Free-Standing Carbon Cloth, Zhen Wei
Electronic Theses and Dissertations
Lithium ion batteries (LIBs) have been used in various applications such as portable electronics, grid storages, and electric vehicles (EVs). Despite its commercial success, further advancement of the battery is necessary to satisfy the increasing demands for low-cost and high- performance energy storage devices as LIB is reaching its theoretical limits. Lithium sulfur battery (LSB) is one of the promising candidates for the next generation energy storage technologies. LSB uses sulfur cathode which is a low-cost and earth abundant material with an extremely high theoretical capacity of 2600 Wh kg-1. Although there have been numerous researches aiming to establish the …
Adsorption Capacity Assessment Of Advance Green Environmental Media To Remove Nutrients From Stormwater-Runoff, Hanan Elhakiem
Adsorption Capacity Assessment Of Advance Green Environmental Media To Remove Nutrients From Stormwater-Runoff, Hanan Elhakiem
Electronic Theses and Dissertations
Best Management Practices (BMPs) in stormwater treatment are a suite of treatment alternatives to deal with pollutant removal problems from stormwater runoff. Biosorption-activated media (BAM) are green sorption media consists of recycled materials have shown excellent nutrient removal as an effective BMP by enhancing physicochemical and microbiological processes. In this study, Iron-Filling Green Environmental Media (denoted as IFGEM-3) and Advanced Green Environmental Media 1 and 2 (denoted as AGEM-1 and AGEM-2) were produced and tested for their adsorption capacities as well as removal and recovery potential for phosphate, nitrate, and ammonia against natural soil (baseline) collected from a stormwater retention …
Interfacial Behavior In Polymer Derived Ceramics And Salt Water Purification Via 2d Mos2, Hao Li
Interfacial Behavior In Polymer Derived Ceramics And Salt Water Purification Via 2d Mos2, Hao Li
Electronic Theses and Dissertations
In the present dissertation, the behavior of the internal potential barrier in a polymer-derived amorphous SiAlCN ceramic was studied by measuring its complex impedance spectra at various dc bias as well as different testing and annealing temperatures. The complex impedance spectra of the polymer-derived a-SiAlCN were measured under various dc bias voltages in a temperature range between 50 and 150°C, as well as different annealing temperatures (1100-1400 °C). All spectra, regardless of temperature and bias, consist of two semi-circular arcs, corresponding to the free-carbon phase and the interface, respectively. The impedance of the free-carbon phase is independent of the bias, …
Fabrication And Characterization Of Nonlinear Optical Ceramics For Random Quasi-Phase-Matching, Xuan Chen
Fabrication And Characterization Of Nonlinear Optical Ceramics For Random Quasi-Phase-Matching, Xuan Chen
Electronic Theses and Dissertations
A number of technologies rely on the conversion of short laser pulses from one spectral domain to another. Efficient frequency conversion is currently obtained in ordered nonlinear optical materials and requires a periodic spatial modulation of their nonlinear coefficient which results in a narrow bandwidth. One can trade off efficiency for more spectral bandwidth by relaxing the strict phase-matching conditions and achieve nonlinear interaction in carefully engineered disordered crystalline aggregates, in a so-called random quasi-phase-matching (rQPM) process. In this dissertation, we examine appropriate fabrication pathways for (1-x)Pb(Mg1/3Nb2/3)O3-xPbTiO3 (PMN-PT) and ZnSe transparent ceramics for applications in the mid-IR. The main challenge …
A Methodology For Data-Driven Decision-Making In Last Mile Delivery Operations, Edgar Gutierrez Franco
A Methodology For Data-Driven Decision-Making In Last Mile Delivery Operations, Edgar Gutierrez Franco
Electronic Theses and Dissertations
Across all industries, from manufacturing to services, decision-makers must deal day to day with the outcomes from past and current decisions that affect their business. Last-mile delivery is the term used in supply chain management to describe the movement of goods from a hub to final destinations. This research proposes a methodology that supports decision making for the execution of last-mile delivery operations in a supply chain. This methodology offers diverse, hybrid, and complementary techniques (e.g., optimization, simulation, machine learning, and geographic information systems) to understand last-mile delivery operations through data-driven decision-making. The hybrid modeling might create better warning systems …
Programmable Low Loss Orthogonal Frequency Coded Surface Acoustic Wave Correlator Filters, Marshall Smith
Programmable Low Loss Orthogonal Frequency Coded Surface Acoustic Wave Correlator Filters, Marshall Smith
Electronic Theses and Dissertations
Simultaneous Transmit and Receive (STAR) communication is being developed as a means of improving spectral efficiency in wireless communication systems. If the obstacle of self-interference can be sufficiently overcome, it is possible to double the spectral efficiency of an equivalent time or frequency division duplexed system. Spread spectrum techniques can reduce self-interference by using orthogonal or pseudo-orthogonal codes to encode the transmit signal and decode the receive signal. Hardware correlator filters are developed for use with STAR radio systems using orthogonal frequency coded (OFC) surface acoustic wave (SAW) devices. OFC is a type of spread spectrum communication that can be …
Hybrid Integration Of Second- And Third-Order Highly Nonlinear Waveguides On Silicon Substrates, Guillermo Fernando Camacho Gonzalez
Hybrid Integration Of Second- And Third-Order Highly Nonlinear Waveguides On Silicon Substrates, Guillermo Fernando Camacho Gonzalez
Electronic Theses and Dissertations
In order to extend the capabilities and applications of silicon photonics, other materials and compatible technologies have been developed and integrated on silicon substrates. A particular class of integrable materials are those with high second- and third-order nonlinear optical properties. This work presents contributions made to nonlinear integrated photonics on silicon substrates, including chalcogenide waveguides for over an octave supercontinuum generation, and rib-loaded thin-film lithium niobate waveguides for highly efficient second-harmonic generation. Through the pursuit of hybrid integration of the two types of waveguides for applications such as on-chip self-referenced optical frequency combs, we have experimentally demonstrated fabrication integrability of …