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Stochastic Optimization And Applications With Endogenous Uncertainties Via Discrete Choice Models, Mengnan Chen Jan 2019

Stochastic Optimization And Applications With Endogenous Uncertainties Via Discrete Choice Models, Mengnan Chen

Electronic Theses and Dissertations

Stochastic optimization is an optimization method that solves stochastic problems for minimizing or maximizing an objective function when there is randomness in the optimization process. In this dissertation, various stochastic optimization problems from the areas of Manufacturing, Health care, and Information Cascade are investigated in networks systems. These stochastic optimization problems aim to make plan for using existing resources to improve production efficiency, customer satisfaction, and information influence within limitation. Since the strategies are made for future planning, there are environmental uncertainties in the network systems. Sometimes, the environment may be changed due to the action of the decision maker. …


Guided Autonomy For Quadcopter Photography, Saif Alabachi Jan 2019

Guided Autonomy For Quadcopter Photography, Saif Alabachi

Electronic Theses and Dissertations

Photographing small objects with a quadcopter is non-trivial to perform with many common user interfaces, especially when it requires maneuvering an Unmanned Aerial Vehicle (C) to difficult angles in order to shoot high perspectives. The aim of this research is to employ machine learning to support better user interfaces for quadcopter photography. Human Robot Interaction (HRI) is supported by visual servoing, a specialized vision system for real-time object detection, and control policies acquired through reinforcement learning (RL). Two investigations of guided autonomy were conducted. In the first, the user directed the quadcopter with a sketch based interface, and periods of …


Filling The Gaps: Common Bottlenose Dolphin (Tursiops Truncatus) Population Dynamics, Structure, And Connectivity Within Florida Panhandle Bays, Sounds, And Estuaries, Christina Toms Jan 2019

Filling The Gaps: Common Bottlenose Dolphin (Tursiops Truncatus) Population Dynamics, Structure, And Connectivity Within Florida Panhandle Bays, Sounds, And Estuaries, Christina Toms

Electronic Theses and Dissertations

At the time of the Deepwater Horizon oil spill in 2010, very little was known about the inshore bottlenose dolphin (Tursiops truncatus) populations hit hardest by the spill. Without previous population demographic data impacts were challenging to assess. My dissertation was designed to build research capacity moving forward by helping to fill data gaps in the western Florida Panhandle. The first study presented here resulted in the first system-wide assessment of seasonal abundance, survival, and site fidelity patterns of bottlenose dolphins that inhabit the Pensacola Bay system. In contrast to a previous study that reported only 33 dolphins, results from …


Approximate In-Memory Computing On Rerams, Salman Anwar Khokhar Jan 2019

Approximate In-Memory Computing On Rerams, Salman Anwar Khokhar

Electronic Theses and Dissertations

Computing systems have seen tremendous growth over the past few decades in their capabilities, efficiency, and deployment use cases. This growth has been driven by progress in lithography techniques, improvement in synthesis tools, architectures and power management. However, there is a growing disparity between computing power and the demands on modern computing systems. The standard Von-Neuman architecture has separate data storage and data processing locations. Therefore, it suffers from a memory-processor communication bottleneck, which is commonly referred to as the 'memory wall'. The relatively slower progress in memory technology compared with processing units has continued to exacerbate the memory wall …


Biomass Density Based Adjustment Of Lidar-Derived Digital Elevation Models: A Machine Learning Approach, Khalid Abdelwahab Jan 2019

Biomass Density Based Adjustment Of Lidar-Derived Digital Elevation Models: A Machine Learning Approach, Khalid Abdelwahab

Electronic Theses and Dissertations

Salt marshes are valued for providing protective and non-protective ecosystem services. Accurate digital elevation models (DEMs) in salt marshes are crucial for modeling storm surges and determining the initial DEM elevations for modelling marsh evolution. Due to high biomass density, lidar DEMs in coastal wetlands are seldom reliable. In an aim to reduce lidar-derived DEM error, several multilinear regression and random forest models were developed and tested to estimate biomass density in the salt marshes near Saint Marks Lighthouse in Crawfordville, Florida. Between summer of 2017 and spring of 2018, two field trips were conducted to acquire true elevation and …


A Smart Uav Platform For Railroad Inspection, Ryan Debevec Jan 2019

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 …


Correctness And Progress Verification Of Non-Blocking Programs, Christina Peterson Jan 2019

Correctness And Progress Verification Of Non-Blocking Programs, Christina Peterson

Electronic Theses and Dissertations

The progression of multi-core processors has inspired the development of concurrency libraries that guarantee safety and liveness properties of multiprocessor applications. The difficulty of reasoning about safety and liveness properties in a concurrent environment has led to the development of tools to verify that a concurrent data structure meets a correctness condition or progress guarantee. However, these tools possess shortcomings regarding the ability to verify a composition of data structure operations. Additionally, verification techniques for transactional memory evaluate correctness based on low-level read/write histories, which is not applicable to transactional data structures that use a high-level semantic conflict detection. In …


Semiconductor Device Modeling, Simulation, And Failure Prediction For Electrostatic Discharge Conditions, Hang Li Jan 2019

Semiconductor Device Modeling, Simulation, And Failure Prediction For Electrostatic Discharge Conditions, Hang Li

Electronic Theses and Dissertations

Electrostatic Discharge (ESD) caused failures are major reliability issues in IC industry. Device modeling for ESD conditions is necessary to evaluate ESD robustness in simulation. Although SPICE model is accurate and efficient for circuit simulations in most cases, devices under ESD conditions operate in abnormal status. SPICE model cannot cover the device operating region beyond normal operation. Thermal failure is one of the main reasons to cause device failure under ESD conditions. A compact model is developed to predict thermal failure with circuit simulators. Instead of considering the detailed failure mechanisms, a failure temperature is introduced to indicate device failure. …


Analysis, Design And Efficiency Optimization Of Power Converters For Renewable Energy Applications, Xi Chen Jan 2019

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 …


Arterial-Level Real-Time Safety Evaluation In The Context Of Proactive Traffic Management, Jinghui Yuan Jan 2019

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 Flow Field And Associated Heat Transfer Within An Asymmetrical Leading Edge Jet Impingement Array, Jorge Torres Jan 2019

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. …


Assessing Pedestrian Safety Conditions On Campus, Morgan Morris Jan 2019

Assessing Pedestrian Safety Conditions On Campus, Morgan Morris

Electronic Theses and Dissertations

Pedestrian-related crashes are a significant safety issue in the United States and cause considerable amounts of deaths and economic cost. Pedestrian safety is an issue that must be uniquely evaluated in a college campus, where pedestrian volumes are dense. The objective of this research is to identify issues at specific locations around UCF and suggest solutions for improvement. To address this problem, a survey that identifies pedestrian safety issues and locations is distributed to UCF students and staff, and an evaluation of drivers reactions to pedestrian to vehicle (P2V) warning systems is studied through the use of a NADS MiniSim …


Design And Implementation Of Silicon-Based Mems Resonators For Application In Ultra Stable High Frequency Oscillators, Sarah Shahraini Jan 2019

Design And Implementation Of Silicon-Based Mems Resonators For Application In Ultra Stable High Frequency Oscillators, Sarah Shahraini

Electronic Theses and Dissertations

The focus of this work is to design and implement resonators for ultra-stable high-frequency ( > 100MHz) silicon-based MEMS oscillators. Specifically, two novel types of resonators are introduced that push the performance of silicon-based MEMS resonators to new limits. Thin film Piezoelectric-on-Silicon (TPoS) resonators have been shown to be suitable for oscillator applications due to their combined high quality factor, coupling efficiency, power handling and doping-dependent temperature-frequency behavior. This thesis is an attempt to utilize the TPoS platform and optimize it for extremely stable high-frequency oscillator applications. To achieve the said objective, two main research venues are explored. Firstly, quality factor …


Learning Internal State Memory Representations From Observation, Josiah Wong Jan 2019

Learning Internal State Memory Representations From Observation, Josiah Wong

Electronic Theses and Dissertations

Learning from Observation (LfO) is a machine learning paradigm that mimics how people learn in daily life: learning how to do something simply by watching someone else do it. LfO has been used in various applications, from video game agent creation to driving a car, but it has always been limited by the inability of an observer to know what a performing entity chooses to remember as they act in an environment. Various methods have either ignored the effects of memory or otherwise made simplistic assumptions about its structure. In this dissertation, we propose a new method, Memory Composition Learning, …


Optimization Algorithms For Deep Learning Based Medical Image Segmentations, Aliasghar Mortazi Jan 2019

Optimization Algorithms For Deep Learning Based Medical Image Segmentations, Aliasghar Mortazi

Electronic Theses and Dissertations

Medical image segmentation is one of the fundamental processes to understand and assess the functionality of different organs and tissues as well as quantifying diseases and helping treatment planning. With ever increasing number of medical scans, the automated, accurate, and efficient medical image segmentation is as unmet need for improving healthcare. Recently, deep learning has emerged as one the most powerful methods for almost all image analysis tasks such as segmentation, detection, and classification and so in medical imaging. In this regard, this dissertation introduces new algorithms to perform medical image segmentation for different (a) imaging modalities, (b) number of …


A Multi-Species Single-Led Hazardous Gas Sensor For Commercial Space Applications, Akshita Parupalli Jan 2019

A Multi-Species Single-Led Hazardous Gas Sensor For Commercial Space Applications, Akshita Parupalli

Electronic Theses and Dissertations

In the interest of furthering both commercial and government-funded opportunities for deep space exploration, the safety of life and equipment onboard must be absolutely certain. In this regard, the presence of any hazardous gases or combustion events onboard space vehicles must be quickly characterized and detected. Several hazardous gases of interest have absorption features in the mid-infrared range and can be detected with an infrared light source, via the principles of absorption spectroscopy. A non-dispersive infrared (NDIR) sensor that follows these principles has been developed to utilize light-emitting diodes (LEDs) for gas detection and quantification. LEDs contain a particular advantage …


An Assessment Of Biosorption Activated Media For The Removal Of Pollutants In Up-Flow Stormwater Treatment Systems, Andrew Hood Jan 2019

An Assessment Of Biosorption Activated Media For The Removal Of Pollutants In Up-Flow Stormwater Treatment Systems, Andrew Hood

Electronic Theses and Dissertations

Nitrogen and phosphorus are often the limiting nutrients for marine and freshwater systems respectively. Additionally, stormwater often contains elevated levels of pathogens which can pollute the receiving water body and impact reuse applications [1-4]. The reduction of limiting nutrients and pathogens is a common primary target for stormwater best management practices (BMPs) [5]. Traditional BMPs, such as retention/detention treatment ponds require large footprints and may not be practical in ultra-urban environments where above ground space is limited. Upflow filters utilizing biosorption activated media (BAM) that can be placed underground offer a small footprint alternative. Additionally, BAM upflow filters can be …


Soft-Error Resilience Framework For Reliable And Energy-Efficient Cmos Logic And Spintronic Memory Architectures, Faris Alghareb Jan 2019

Soft-Error Resilience Framework For Reliable And Energy-Efficient Cmos Logic And Spintronic Memory Architectures, Faris Alghareb

Electronic Theses and Dissertations

The revolution in chip manufacturing processes spanning five decades has proliferated high performance and energy-efficient nano-electronic devices across all aspects of daily life. In recent years, CMOS technology scaling has realized billions of transistors within large-scale VLSI chips to elevate performance. However, these advancements have also continually augmented the impact of Single-Event Transient (SET) and Single-Event Upset (SEU) occurrences which precipitate a range of Soft-Error (SE) dependability issues. Consequently, soft-error mitigation techniques have become essential to improve systems' reliability. Herein, first, we proposed optimized soft-error resilience designs to improve robustness of sub-micron computing systems. The proposed approaches were developed to …


Lithium Polysulfide Battery With Improved Capacity And Cycle Performance Using Carbon Black Coated Free-Standing Carbon Cloth, Zhen Wei Jan 2019

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 …


Development Of S-Nitroso-N-Acetylpenicillamine (Snap) Impregnated Medical Grade Polyvinyl Chloride For Antimicrobial Medical Device Interfaces, Corbin Feit Jan 2019

Development Of S-Nitroso-N-Acetylpenicillamine (Snap) Impregnated Medical Grade Polyvinyl Chloride For Antimicrobial Medical Device Interfaces, Corbin Feit

Electronic Theses and Dissertations

In the clinical setting, polyvinyl chloride (PVC) accounts for 25% of all polymers used in medical device applications. However, medical devices fabricated with PVC, such as endotracheal tubes, extracorporeal circuits (ECCs), or intravenous catheters suffer from thrombosis and infection. Mortality associated with hospital associated infections (HAIs) exceed 100,000 deaths each year. One method to overcome these challenges is to develop bioactive polymers with nitric oxide (NO) release. Nitric oxide exhibits many physiological roles including, antibacterial, antithrombic, anti-inflammatory activity. In this study, Tygon® PVC tubing was impregnated with a NO donor molecule, S-nitroso-N-acetylpenicillamine (SNAP), via a simple solvent-swelling-impregnation method, where polymer …


Reliability And Robustness Enhancement Of Cooperative Vehicular Systems: A Bayesian Machine Learning Perspective, Hossein Nourkhiz Mahjoub Jan 2019

Reliability And Robustness Enhancement Of Cooperative Vehicular Systems: A Bayesian Machine Learning Perspective, Hossein Nourkhiz Mahjoub

Electronic Theses and Dissertations

Autonomous vehicles are expected to greatly transform the transportation domain in the near future. Some even envision that the human drivers may be fully replaced by automated systems. It is plausible to assume that at least a significant part of the driving task will be done by automated systems in not a distant future. Although we are observing a rapid advance towards this goal, which gradually pushes the traditional human-based driving toward more advanced autonomy levels, the full autonomy concept still has a long way before being completely fulfilled and realized due to numerous technical and societal challenges. During this …


Probabilistic Spatio-Magnitude Sinkhole Hazard Analysis For East Central Flrodia, Yong Je Kim Jan 2019

Probabilistic Spatio-Magnitude Sinkhole Hazard Analysis For East Central Flrodia, Yong Je Kim

Electronic Theses and Dissertations

In Karst areas, sinkholes are a major geohazard that creates damage and economic loss to building and civil infrastructure. The main goal of the proposed study is to develop a probabilistic spatio-magnitude sinkhole susceptibility model that predicts the potential of sinkhole occurrence on a regional scale. The dissertation presents statistical techniques such as frequency ratio (FR) and logistic regression (LR), and a machine learning technique such as artificial neural network (ANN) to develop the sinkhole hazard models. The study area was limited to the East Central Floria (ECF) region. Seven hydrogeological factors were identified as key contributing factors to sinkhole …


Automated Synthesis Of Memristor Crossbar Networks, Dwaipayan Chakraborty Jan 2019

Automated Synthesis Of Memristor Crossbar Networks, Dwaipayan Chakraborty

Electronic Theses and Dissertations

The advancement of semiconductor device technology over the past decades has enabled the design of increasingly complex electrical and computational machines. Electronic design automation (EDA) has played a significant role in the design and implementation of transistor-based machines. However, as transistors move closer toward their physical limits, the speed-up provided by Moore's law will grind to a halt. Once again, we find ourselves on the verge of a paradigm shift in the computational sciences as newer devices pave the way for novel approaches to computing. One of such devices is the memristor -- a resistor with non-volatile memory. Memristors can …


Assessing The Safety And Operational Benefits Of Connected And Automated Vehicles: Application On Different Roadways, Weather, And Traffic Conditions, Md Sharikur Rahman Jan 2019

Assessing The Safety And Operational Benefits Of Connected And Automated Vehicles: Application On Different Roadways, Weather, And Traffic Conditions, Md Sharikur Rahman

Electronic Theses and Dissertations

Connected and automated vehicle (CAV) technologies have recently drawn an increasing attention from governments, vehicle manufacturers, and researchers. Connected vehicle (CV) technologies provide real-time information about the surrounding traffic condition (i.e., position, speed, acceleration) and the traffic management center's decisions. The CV technologies improve the safety by increasing driver situational awareness and reducing crashes through vehicle-to-vehicle (V2V) and vehicle-to-infrastructure (V2I). Vehicle platooning with CV technologies is another key element of the future transportation systems which helps to simultaneously enhance traffic operations and safety. CV technologies can also further increase the efficiency and reliability of automated vehicles (AV) by collecting real-time …


Programmable Low Loss Orthogonal Frequency Coded Surface Acoustic Wave Correlator Filters, Marshall Smith Jan 2019

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 …


Development Of In Vitro Point Of Care Diagnostics (Ivpcd) Based On Aptamers Integrated Biosensors, Nileshi Saraf Jan 2019

Development Of In Vitro Point Of Care Diagnostics (Ivpcd) Based On Aptamers Integrated Biosensors, Nileshi Saraf

Electronic Theses and Dissertations

The global market for the medical diagnostic industry is worth 25 billion dollars in the United States and is expected to grow exponentially each year. Presently available methods for biodetection, such as immunoassays, chemiluminescence and fluorescent based assays are expensive, time consuming and require skilled labor with high-end instruments. Therefore, development of novel, passive colorimetric sensors and diagnostic technologies for detection and surveillance is of utmost importance especially in resource constrained communities. The present work focusses on developing novel and advanced in vitro biodiagnostic tools based on aptamer integrated biosensors for an early detection of specific viral proteins or small …


Utilizing Edge In Iot And Video Streaming Applications To Reduce Bottlenecks In Internet Traffic, Kutalmis Akpinar Jan 2019

Utilizing Edge In Iot And Video Streaming Applications To Reduce Bottlenecks In Internet Traffic, Kutalmis Akpinar

Electronic Theses and Dissertations

There is a large increase in the surge of data over Internet due to the increasing demand on multimedia content. It is estimated that 80% of Internet traffic will be video by 2022, according to a recent study. At the same time, IoT devices on Internet will double the human population. While infrastructure standards on IoT are still nonexistent, enterprise solutions tend to encourage cloud-based solutions, causing an additional surge of data over the Internet. This study proposes solutions to bring video traffic and IoT computation back to the edges of the network, so that costly Internet infrastructure upgrades are …


Improving Turbine Performance: A Contribution To The Understanding Of Heat Transfer And Vortical Structures In Staggered Pin Fin Arrays, Marcel Otto Jan 2019

Improving Turbine Performance: A Contribution To The Understanding Of Heat Transfer And Vortical Structures In Staggered Pin Fin Arrays, Marcel Otto

Electronic Theses and Dissertations

Through the comparison of flow structures, velocity contours, turbulence statistics, and additional flow quantities, the error sources of RANS are qualitatively described. The findings in this work will help gas turbine design engineers to tweak their turbulence models and give guidance on the interpretation of their results. The novelty is the application of the transient TLC method on this type of geometry as well as the near-wall PIV measurements. The advancements in additive manufacturing disrupt the classic turbine cooling development for casted airfoils. More and more complicated shapes and cooling schemes are possible. Nonetheless, a detailed physical understanding of fundamental …


A Theoretical, Numerical, And Experimental Study Of Trapped Droplet Coalescence And Mixing, Passively And Under Electric Field, Alireza Karbalaei Baba Jan 2019

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 …


Stragglers-Robust First-Order Distributed Optimization Algorithms Over Networks Utilizing Gradient Coding, Elie Atallah Jan 2019

Stragglers-Robust First-Order Distributed Optimization Algorithms Over Networks Utilizing Gradient Coding, Elie Atallah

Electronic Theses and Dissertations

This dissertation considers distributed algorithms for centralized and decentralized networks that solve general convex optimization problems. First, a centralized algorithm is explored for parameter server networks robust to the straggler problem. It is proved that the server nodes' estimates converge to the minimizer of the global objective function with connections vulnerable to an allowed number of stragglers. We then show that convergence is also attained in other different cases: Either by using only the received local gradients scenario or the scenario of using delayed local gradients for the non received gradients. Concurrently, the convergence rates for the above aforementioned scenarios …