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Load Estimation, Structural Identification And Human Comfort Assessment Of Flexible Structures, Ozan Celik Jan 2017

Load Estimation, Structural Identification And Human Comfort Assessment Of Flexible Structures, Ozan Celik

Electronic Theses and Dissertations

Stadiums, pedestrian bridges, dance floors, and concert halls are distinct from other civil engineering structures due to several challenges in their design and dynamic behavior. These challenges originate from the flexible inherent nature of these structures coupled with human interactions in the form of loading. The investigations in past literature on this topic clearly state that the design of flexible structures can be improved with better load modeling strategies acquired with reliable load quantification, a deeper understanding of structural response, generation of simple and efficient human-structure interaction models and new measurement and assessment criteria for acceptable vibration levels. In contribution …

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High Dynamic Range Display Systems, Ruidong Zhu Jan 2017

High Dynamic Range Display Systems, Ruidong Zhu

Electronic Theses and Dissertations

High contrast ratio (CR) enables a display system to faithfully reproduce the real objects. However, achieving high contrast, especially high ambient contrast (ACR), is a challenging task. In this dissertation, two display systems with high CR are discussed: high ACR augmented reality (AR) display and high dynamic range (HDR) display. For an AR display, we improved its ACR by incorporating a tunable transmittance liquid crystal (LC) film. The film has high tunable transmittance range, fast response time, and is fail-safe. To reduce the weight and size of a display system, we proposed a functional reflective polarizer, which can also help …

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Two-Component Covalent Inhibitors (Tcci) Of The Human Immunodeficiency Virus Reverse Transcriptase (Hiv-Rt), Carlos Ledezma Jan 2017

Two-Component Covalent Inhibitors (Tcci) Of The Human Immunodeficiency Virus Reverse Transcriptase (Hiv-Rt), Carlos Ledezma

Electronic Theses and Dissertations

The traditional design of nucleoside reverse transcriptase inhibitors (NRTI's) involves the synthesis of chain-terminated nucleoside analogs. HIV-RT has relatively low fidelity which facilitates mutations that confer resistance towards NRTI's, also, drug promiscuity from NRTI's result in various side-effects that lead to poor patient adherence to treatment. We designed and tested two-component covalent inhibitors against HIV-RT. Our inhibitor design results in higher specificity due to its binary approach, which has previously been used in biosensing applications, where both components are necessary for therapeutic effect, and lower chances for mutagenesis because of its inhibitory action. The TCCI approach results in up to …

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Light Trapping In Thin Film Crystalline Silicon Solar Cells, Javaneh Boroumand Azad Jan 2017

Light Trapping In Thin Film Crystalline Silicon Solar Cells, Javaneh Boroumand Azad

Electronic Theses and Dissertations

This dissertation presents numerical and experimental studies of a unified light trapping approach that is extremely important for all practical solar cells. A 2D hexagonal Bravais lattice diffractive pattern is studied in conjunction with the verification of the reflection mechanisms of single and double layer anti-reflective coatings in the broad range of wavelength 400 nm - 1100 nm. By varying thickness and conformity, we obtained the optimal parameters which minimize the broadband reflection from the nanostructured crystalline silicon surface over a wide range of angle 0°-65°. While the analytical design of broadband, angle independent anti-reflection coatings on nanostructured surfaces remains …

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High Power Fiber Lasers And Fiber Devices, Zeinab Sanjabieznaveh Jan 2017

High Power Fiber Lasers And Fiber Devices, Zeinab Sanjabieznaveh

Electronic Theses and Dissertations

Fiber lasers and fiber amplifiers have experienced considerable improvements in recent years and demonstrated remarkable power scalability. However, due to high optical intensity in the core, the performance of high power fiber lasers is limited by detrimental nonlinear processes, such as four-wave mixing, self-phase modulation, stimulated Brillouin scattering, and stimulated Raman scattering. To mitigate nonlinear effects, very large mode area (LMA) fibers, which exhibit a mode field diameter larger than 30 ?m have been developed. However, for larger core sizes the discrimination capabilities of conventional fiber designs decrease, consequently, LMA fibers are not strictly single mode which ultimately at high …

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Atomic-Scale Simulation Of Physical And Chemical Processes During Space Weathering And Planet Formation, Abrar Quadery Jan 2017

Atomic-Scale Simulation Of Physical And Chemical Processes During Space Weathering And Planet Formation, Abrar Quadery

Electronic Theses and Dissertations

We investigate the mechanisms of space weathering and dust grain collisions, two topics of interests from planetary sciences, using atomic-scale simulations. Space weathering is the change in chemical and physical properties of minerals exposed to solar radiation and micrometeorite bombardment on surfaces of airless planetary bodies like the Moon and asteroids. An understanding of the connection between the surface evolution of the minerals and the underlying thermodynamic and kinetic factors is still missing. We address this issue and determine the time evolution of Frenkel defects in the silicate minerals olivine ((Mg,Fe)$_2$SiO$_4$) and orthopyroxene ((Mg,Fe)SiO$_3$) using molecular dynamics with a pair …

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Novel Computational Methods For Integrated Circuit Reverse Engineering, Travis Meade Jan 2017

Novel Computational Methods For Integrated Circuit Reverse Engineering, Travis Meade

Electronic Theses and Dissertations

Production of Integrated Circuits (ICs) has been largely strengthened by globalization. System-on-chip providers are capable of utilizing many different providers which can be responsible for a single task. This horizontal structure drastically improves to time-to-market and reduces manufacturing cost. However, untrust of oversea foundries threatens to dismantle the complex economic model currently in place. Many Intellectual Property (IP) consumers become concerned over what potentially malicious or unspecified logic might reside within their application. This logic which is inserted with the intention of causing harm to a consumer has been referred to as a Hardware Trojan (HT). To help IP consumers, …

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Method For Real-Time Signal Selection For Passive Coherent Location Systems, Nicholas Johnson Jan 2017

Method For Real-Time Signal Selection For Passive Coherent Location Systems, Nicholas Johnson

Electronic Theses and Dissertations

Passive coherent location (PCL) systems use signals of opportunity to perform traditional radar detection, targeting, and tracking functions. Traditionally these signals include FM radio, digital TV, GSM, and GPS because of their availability in most urban environments. A benefit of having an abundance of signals is the ability to choose which of those best meet the desired system intentions. For example, one may want to choose a digital TV signal over an FM radio signal due to its range resolution characteristics. This work presents a novel algorithm for characterizing commercial signals for use in a PCL system. By analyzing each …

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The Physical Properties And Composition Of Main-Belt Asteroids From Infrared Spectroscopy, Zoe Landsman Jan 2017

The Physical Properties And Composition Of Main-Belt Asteroids From Infrared Spectroscopy, Zoe Landsman

Electronic Theses and Dissertations

Asteroids are the remnants of planet formation, and as such, they represent a record of the physical and chemical conditions in the early solar system and its evolution over the past 4.6 billion years. Asteroids are relatively accessible by spacecraft, and thus may be a source of the raw materials necessary for future human exploration and settlement of space. Those on Earth-crossing orbits pose impact hazards for which mitigation strategies must be developed. For these reasons, several missions to asteroids are in progress or planned with the support of the National Aeronautics and Space Administration (NASA) and other national space …

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Nitrogen-Containing Materials For Mechanochemical Synthesis, Luminescence Analysis, And Heterogeneous Catalysis, David Nash Jan 2017

Nitrogen-Containing Materials For Mechanochemical Synthesis, Luminescence Analysis, And Heterogeneous Catalysis, David Nash

Electronic Theses and Dissertations

Various inorganic nitrogen-containing materials have been exploited for their different properties. Several nitride materials are commercially attractive due to their mechanical properties making them suitable for ceramic industries and wide bandgaps fitting for use as semiconductor and insulator materials, as well as optoelectronics. Nitride materials can exhibit versatility in applications such as the use of gallium nitride to make blue LEDs, nitrides of titanium and silicon being utilized as medical implants for their chemical inertness and hardness, and the heavy use of boron nitride as a solid lubricant in the cosmetic industry. Amines have been used as nitrogen-containing organic ligands …

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A Deoxyribozyme Sensor And Isothermal Amplification For Human Sex Determination, Alexandra Smith Jan 2017

A Deoxyribozyme Sensor And Isothermal Amplification For Human Sex Determination, Alexandra Smith

Electronic Theses and Dissertations

Ribozymes are known to catalyze biochemical reactions and behave like enzymes. They are naturally occurring and have very diverse functions within a cell. After investigating ribozymes that next step was to find if DNA can exhibit the same characteristics since RNA and DNA only differ by a ribose 2'-hydroxyl group. This evolution in curiosity gave rise to artificial DNA enzymes that can catalyze certain reactions and have been created by in vitro selection methods. Due to the ability to manipulate and control DNA hybridization, the deoxyribozyme is advantageous to the field of molecular diagnostics. Other hybridization probes like Taqman for …

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Advanced Control Techniques For Efficiency And Power Density Improvement Of A Three-Phase Microinverter, Seyed Milad Tayebi Jan 2017

Advanced Control Techniques For Efficiency And Power Density Improvement Of A Three-Phase Microinverter, Seyed Milad Tayebi

Electronic Theses and Dissertations

Inverters are widely used in photovoltaic (PV) based power generation systems. Most of these systems have been based on medium to high power string inverters. Microinverters are gaining popularity over their string inverter counterparts in PV based power generation systems due to maximized energy harvesting, high system reliability, modularity, and simple installation. They can be deployed on commercial buildings, residential rooftops, electric poles, etc and have a huge potential market. Emerging trend in power electronics is to increase power density and efficiency while reducing cost. A powerful tool to achieve these objectives is the development of an advanced control system …

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A Universal Electrochemical Biosensor For The Detection Of Nucleic Acids Based On A Four-Way Junction Structure, Dawn Mills Jan 2017

A Universal Electrochemical Biosensor For The Detection Of Nucleic Acids Based On A Four-Way Junction Structure, Dawn Mills

Electronic Theses and Dissertations

Electrochemical hybridization sensors have been explored extensively for analysis of specific nucleic acids. However, commercialization of the platform is hindered by the need for attachment of separate oligonucleotide probes complementary to a RNA or DNA target to an electrode's surface. This dissertation demonstrates that a single probe can be used to analyze several nucleic acid targets of different lengths with high selectivity, low cost and can be regenerated in 30 seconds by a simple water rinse. The universal electrochemical four-way junction (4J)-forming (UE4J) sensor consists of a universal DNA stem-loop (USL) probe attached to the electrode's surface and two adaptor …

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Harnessing Spatial Intensity Fluctuations For Optical Imaging And Sensing, Milad Akhlaghi Bouzan Jan 2017

Harnessing Spatial Intensity Fluctuations For Optical Imaging And Sensing, Milad Akhlaghi Bouzan

Electronic Theses and Dissertations

Properties of light such as amplitude and phase, temporal and spatial coherence, polarization, etc. are abundantly used for sensing and imaging. Regardless of the passive or active nature of the sensing method, optical intensity fluctuations are always present! While these fluctuations are usually regarded as noise, there are situations where one can harness the intensity fluctuations to enhance certain attributes of the sensing procedure. In this thesis, we developed different sensing methodologies that use statistical properties of optical fluctuations for gauging specific information. We examine this concept in the context of three different aspects of computational optical imaging and sensing. …

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Network Partitioning In Distributed Agent-Based Models, Antoniya Petkova Jan 2017

Network Partitioning In Distributed Agent-Based Models, Antoniya Petkova

Electronic Theses and Dissertations

Agent-Based Models (ABMs) are an emerging simulation paradigm for modeling complex systems, comprised of autonomous, possibly heterogeneous, interacting agents. The utility of ABMs lies in their ability to represent such complex systems as self-organizing networks of agents. Modeling and understanding the behavior of complex systems usually occurs at large and representative scales, and often obtaining and visualizing of simulation results in real-time is critical. The real-time requirement necessitates the use of in-memory computing, as it is difficult and challenging to handle the latency and unpredictability of disk accesses. Combining this observation with the scale requirement emphasizes the need to use …

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Linking Climate Change And Socio-Economic Impact For Long-Term Urban Growth In Three Mega-Cities, Qi Lu Jan 2017

Linking Climate Change And Socio-Economic Impact For Long-Term Urban Growth In Three Mega-Cities, Qi Lu

Electronic Theses and Dissertations

Urbanization has become a global trend under the impact of population growth, socio-economic development, and globalization. However, the interactions between climate change and urban growth in the context of economic geography are unclear due to missing links in between the recent planning megacities. This study aims to conduct a multi-temporal change analysis of land use and land cover in New York City, City of London, and Beijing using a cellular automata-based Markov chain model collaborating with fuzzy set theory and multi-criteria evaluation to predict the city's future land use changes for 2030 and 2050 under the background of climate change. …

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Annual Water Balance Model Based On Generalized Proportionality Relationship And Its Applications, Yin Tang Jan 2017

Annual Water Balance Model Based On Generalized Proportionality Relationship And Its Applications, Yin Tang

Electronic Theses and Dissertations

The main goal of this dissertation research is to derive a type of conceptual models for annual water balance at the watershed scale. The proportionality relationship from the Soil Conservation Service Curve Number method was generalized to annual scale for deriving annual water balance model. As a result, a one-parameter Budyko equation was derived based on one-stage partitioning; and a four-parameter Budyko equation was derived based on two-stage partitioning. The derived equations balance model parsimony and representation of dominant hydrologic processes, and provide a new framework to disentangle the roles of climate variability, vegetation, soil and topography on long-term water …

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Improving Safety Under Reduced Visibility Based On Multiple Countermeasures And Approaches Including Connected Vehicles, Yina Wu Jan 2017

Improving Safety Under Reduced Visibility Based On Multiple Countermeasures And Approaches Including Connected Vehicles, Yina Wu

Electronic Theses and Dissertations

The effect of low visibility on both crash occurrence and severity is a major concern in the traffic safety field. Different approaches were utilized in this research to analyze the effects of fog on traffic safety and evaluate the effectiveness of different fog countermeasures. First, a "Crash Risk Increase Indicator (CRII)" was proposed to explore the differences of crash risk between fog and clear conditions. A binary logistic regression model was applied to link the increase of crash risk with traffic flow characteristics. Second, a new algorithm was proposed to evaluate the rear-end crash risk under fog conditions. Logistic and …

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Online, Supervised And Unsupervised Action Localization In Videos, Khurram Soomro Jan 2017

Online, Supervised And Unsupervised Action Localization In Videos, Khurram Soomro

Electronic Theses and Dissertations

Action recognition classifies a given video among a set of action labels, whereas action localization determines the location of an action in addition to its class. The overall aim of this dissertation is action localization. Many of the existing action localization approaches exhaustively search (spatially and temporally) for an action in a video. However, as the search space increases with high resolution and longer duration videos, it becomes impractical to use such sliding window techniques. The first part of this dissertation presents an efficient approach for localizing actions by learning contextual relations between different video regions in training. In testing, …

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Learning Kernel-Based Approximate Isometries, Mahlagha Sedghi Jan 2017

Learning Kernel-Based Approximate Isometries, Mahlagha Sedghi

Electronic Theses and Dissertations

The increasing availability of public datasets offers an inexperienced opportunity to conduct data-driven studies. Metric Multi-Dimensional Scaling aims to find a low-dimensional embedding of the data, preserving the pairwise dissimilarities amongst the data points in the original space. Along with the visualizability, this dimensionality reduction plays a pivotal role in analyzing and disclosing the hidden structures in the data. This work introduces Sparse Kernel-based Least Squares Multi-Dimensional Scaling approach for exploratory data analysis and, when desirable, data visualization. We assume our embedding map belongs to a Reproducing Kernel Hilbert Space of vector-valued functions which allows for embeddings of previously unseen …

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Complex Affect Recognition In The Wild, Behnaz Nojavanasghari Jan 2017

Complex Affect Recognition In The Wild, Behnaz Nojavanasghari

Electronic Theses and Dissertations

Artificial social intelligence is a step towards human-like human-computer interaction. One important milestone towards building socially intelligent systems is enabling computers with the ability to process and interpret the social signals of humans in the real world. Social signals include a wide range of emotional responses from a simple smile to expressions of complex affects. This dissertation revolves around computational models for social signal processing in the wild, using multimodal signals with an emphasis on the visual modality. We primarily focus on complex affect recognition with a strong interest in curiosity. In this dissertation,we ?rst present our collected dataset, EmoReact. …

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End To End Brain Fiber Orientation Estimation Using Deep Learning, Nandakishore Puttashamachar Jan 2017

End To End Brain Fiber Orientation Estimation Using Deep Learning, Nandakishore Puttashamachar

Electronic Theses and Dissertations

In this work, we explore the various Brain Neuron tracking techniques, one of the most significant applications of Diffusion Tensor Imaging. Tractography is a non-invasive method to analyze underlying tissue micro-structure. Understanding the structure and organization of the tissues facilitates a diagnosis method to identify any aberrations which can occur within tissues due to loss of cell functionalities, provides acute information on the occurrences of brain ischemia or stroke, the mutation of certain neurological diseases such as Alzheimer, multiple sclerosis and so on. Under all these circumstances, accurate localization of the aberrations in efficient manner can help save a life. …

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Ultra-Efficient Cascaded Buck-Boost Converter, Anirudh Ashok Pise Jan 2017

Ultra-Efficient Cascaded Buck-Boost Converter, Anirudh Ashok Pise

Electronic Theses and Dissertations

This thesis presents various techniques to achieve ultra-high-efficiency for Cascaded-Buck-Boost converter. A rigorous loss model with component non linearity is developed and validated experimentally. An adaptive-switching-frequency control is discussed to optimize weighted efficiency. Some soft-switching techniques are discussed. A low-profile planar-nanocrystalline inductor is developed and various design aspects of core and copper design are discussed. Finite-element-method is used to examine and visualize the inductor design. By implementing the above, a peak efficiency of over 99.2 % is achieved with a power density of 6 kW/L and a maximum profile height of 7 mm is reported. This converter finds many applications …

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Reducing Sulfuric Acid Pretreatment In A Nanofiltration Process Treating Surficial Groundwater, Carlyn Higgins Jan 2017

Reducing Sulfuric Acid Pretreatment In A Nanofiltration Process Treating Surficial Groundwater, Carlyn Higgins

Electronic Theses and Dissertations

Nanofiltration (NF) is a pressure driven membrane process employed in drinking water treatment that requires pretreatment for reliable operation. The objective of this research was to determine if NF membranes can proficiently operate with a decreased or eliminated dose of sulfuric acid pretreatment. When used as pretreatment, sulfuric acid prevents calcium carbonate scaling on NF membranes, yet is costly, hazardous, and imparts high sulfate concentrations to NF feed and concentrate streams. To conduct this research, a 0.324 million gallon per day (MGD) NF pilot plant was operated for 3,855 run-hours at a flux rate of 15 gallons per square foot-day. …

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Development Of An Adaptive Restoration Tool For A Self-Healing Smart Grid, Amir Golshani Jan 2017

Development Of An Adaptive Restoration Tool For A Self-Healing Smart Grid, Amir Golshani

Electronic Theses and Dissertations

Large power outages become more commonplace due to the increase in both frequency and strength of natural disasters and cyber-attacks. The outages and blackouts cost American industries and business billions of dollars and jeopardize the lives of hospital patients. The losses can be greatly reduced with a fast, reliable and flexible restoration tool. Fast recovery and successfully adapting to extreme events are critical to build a resilient, and ultimately self-healing power grid. This dissertation is aimed to tackle the challenging task of developing an adaptive restoration decision support system (RDSS). The RDSS determines restoration actions both in planning and real-time …

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Polyurethane Fiber Reinforced Polymer Strengthening Of Shear Deficient Reinforced Concrete Beams, Yasir Al-Lebban Jan 2017

Polyurethane Fiber Reinforced Polymer Strengthening Of Shear Deficient Reinforced Concrete Beams, Yasir Al-Lebban

Electronic Theses and Dissertations

The use of externally-bonded fiber-reinforced polymer (FRP) composites has been established as an effective means for the strengthening of shear-deficient reinforced concrete (RC) flexural members. Epoxy-based wet layup systems were predominantly employed in previous studies. In this study, carbon FRP pre-impregnated with polyurethane resin is utilized in strengthening shear-deficient RC beams and compared to an epoxy resin. Fourteen small-scale (96 in span, 6 in width, and 12 in height) and five large-scale (132 in span, 12 in width, and 17 in height) flexural specimens were tested, considering FRP system type (polyurethane versus epoxy), size effect, shear span-to-depth ratio, FRP configuration …

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Pervasive Secure Content Delivery Networks Implementation, Hector Lugo-Cordero Jan 2017

Pervasive Secure Content Delivery Networks Implementation, Hector Lugo-Cordero

Electronic Theses and Dissertations

Over the years, communication networks have been shifting their focus from providing connectivity in a client/server model to providing a service or content. This shift has led to topic areas like Service-Oriented Architecture (SOA), Heterogeneous Wireless Mesh Networks, and Ubiquitous Computing. Furthermore, probably the broadest of these areas which embarks all is the Internet of Things (IoT). The IoT is defined as an Internet where all physical entities (e.g., vehicles, appliances, smart phones, smart homes, computers, etc.), which we interact daily are connected and exchanging data among themselves and users. The IoT has become a global goal for companies, researchers, …

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Learning Dynamic Network Models For Complex Social Systems, Alireza Hajibagheri Jan 2017

Learning Dynamic Network Models For Complex Social Systems, Alireza Hajibagheri

Electronic Theses and Dissertations

Human societies are inherently complex and highly dynamic, resulting in rapidly changing social networks, containing multiple types of dyadic interactions. Analyzing these time-varying multiplex networks with approaches developed for static, single layer networks often produces poor results. To address this problem, our approach is to explicitly learn the dynamics of these complex networks. This dissertation focuses on five problems: 1) learning link formation rates; 2) predicting changes in community membership; 3) using time series to predict changes in network structure; 4) modeling coevolution patterns across network layers and 5) extracting information from negative layers of a multiplex network. To study …

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Academic Blade Geometries For Baseline Comparisons Of Forced Vibration Response Predictions, James Little Jan 2017

Academic Blade Geometries For Baseline Comparisons Of Forced Vibration Response Predictions, James Little

Electronic Theses and Dissertations

Predicting the damping associated with underplatform dampers remains a challenge in turbomachinery blade and friction damper design. Turbomachinery blade forced response analysis methods usually rely on nonlinear codes and reduced order models to predict vibration characteristics of blades. Two academic blade geometries coupled with underplatform dampers are presented here for comparison of these model reduction and forced response simulation techniques. The two blades are representative of free-standing turbine blades and exhibit qualitatively similar behavior as highly-complex industrial blades. This thesis fully describes the proposed academic blade geometries and models; it further analyzes and predicts the blades forced response characteristics using …

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Hydrologic Controls On The Natural Drainage Networks Extracted From High-Resolution Topographic Data, Milad Hooshyar Jan 2017

Hydrologic Controls On The Natural Drainage Networks Extracted From High-Resolution Topographic Data, Milad Hooshyar

Electronic Theses and Dissertations

Drainage networks are important geomorphologic and hydrologic features which significantly control runoff generation. Drainage networks are composed of unchannelized valleys and channels. At valley heads, flow changes from unconfined sheet flow on the hillslope to confined flow in valley. Localized confined flow dominates in valleys as a result of convergent topography with positive curvature. Channels initiate at some distance down from the valley head, and the transition from unchannelized valley to channel is referred to as the channel head. Channel heads occur at a point where fluvial transport dominates over diffusive transport. From the hydrologic perspective, channels are categorized as …

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