Physical Sciences and Mathematics Commons^™

Scatterometry Of 50 Nm Half Pitch Features, Ruichao Zhu

Optical Science and Engineering ETDs

Metrology technologies are an essential adjunct to Integrated Circuit (I.C.) Semiconductor manufacturing. Scatterometry, an optical metrology, was chosen to measure 50 nm half pitch feature structures. A bread-board scatterometry system has been assembled to provide a non-contact, non-destructive, accurate and flexible measurement. A real-time, on-line scatterometry system has also been demonstrated and proven to provide a high throughput measurement.

Three different types of samples have been measured using the scatterometry setup. The wire-grid polarizer (WGP) sample has been made by Jet and Flash Nanoimprint Lithography with ~100 nm pitch and ~50 nm wide ~200 nm tall Al gratings on fused …

Algorithm For Premature Ventricular Contraction Detection From A Subcutaneous Electrocardiogram Signal, Iris Lynn Shelly

Dissertations and Theses

Cardiac arrhythmias occur when the normal pattern of electrical signals in the heart breaks down. A premature ventricular contraction (PVC) is a common type of arrhythmia that occurs when a heartbeat originates from an ectopic focus within the ventricles rather than from the sinus node in the right atrium. This and other arrhythmias are often diagnosed with the help of an electrocardiogram, or ECG, which records the electrical activity of the heart using electrodes placed on the skin. In an ECG signal, a PVC is characterized by both timing and morphological differences from a normal sinus beat.

An implantable cardiac …

Vulnerability Analysis And Security Framework For Zigbee Communication In Iot, Charbel Azzi

UNLV Theses, Dissertations, Professional Papers, and Capstones

Securing IoT (Internet of Things) systems in general, regardless of the communication technology used, has been the concern of many researchers and private companies. As for ZigBee security concerns, much research and many experiments have been conducted to better predict the nature of potential security threats. In this research we are addressing several ZigBee vulnerabilities by performing first hand experiments and attack simulations on ZigBee protocol. This will allow us to better understand the security issues surveyed and find ways to mitigate them. Based on the attack simulations performed and the survey conducted, we have developed a ZigBee IoT framework …

Acoustic Detection, Source Separation, And Classification Algorithms For Unmanned Aerial Vehicles In Wildlife Monitoring And Poaching, Carlo Lopez-Tello

UNLV Theses, Dissertations, Professional Papers, and Capstones

This work focuses on the problem of acoustic detection, source separation, and classification under noisy conditions. The goal of this work is to develop a system that is able to detect poachers and animals in the wild by using microphones mounted on unmanned aerial vehicles (UAVs). The classes of signals used to detect wildlife and poachers include: mammals, birds, vehicles and firearms. The noise signals under consideration include: colored noises, UAV propeller and wind noises.

The system consists of three sub-systems: source separation (SS), signal detection, and signal classification. Non-negative Matrix Factorization (NMF) is used for source separation, and random …

Plasmonic Devices Based On Transparent Conducting Oxides For Near Infrared Applications, Kim Jongbum

Open Access Dissertations

In the past decade, there have been many breakthroughs in the field of plasmonics and nanophotonics that have enabled optical devices with unprecedented functionalities. Even though remarkable demonstration of at photonic devices has been reported, constituent materials are limited to the noble metals such as gold (Au) and silver (Ag) due to their abundance of free electrons which enable the support of plasmon resonances in the visible range. With the strong demand for extension of the optical range of plasmonic applications, it is now a necessity to explore and develop alternative materials which can overcome intrinsic issues of noble metals …

Fabrication Of Infrared Photodetectors Utilizing Lead Selenide Nanocrystals, Justin Anthony Hill

Graduate Theses and Dissertations

Colloidal lead selenide and lead selenide / lead sulfide core/shell nanocrystals were grown using a wet chemical synthesis procedure. Absorbance and photoluminescence measurements were made to verify the quality of the produced nanocrystals. Absorbance spectra were measured at room temperature, while photoluminescence spectra were measured at 77 K. Organic ligands were exchanged for shorter ligands in order to increase the conductivity of the nanocrystals. Absorption and PL spectra for both core and core/shell nanocrystals were compared. Interdigital photodetector devices with varying channel widths were fabricated by depositing gold onto a glass substrate. Lead selenide nanocrystals were deposited onto these metallic …

Interactive Physics And Characteristics Of Photons And Photoelectrons In Hyperbranched Zinc Oxide Nanostructures, Garrett Edward Torix

Graduate Theses and Dissertations

As is commonly known, the world is full of technological wonders, where a multitude of electronic devices and instruments continuously help push the boundaries of scientific knowledge and discovery. These new devices and instruments of science must be utilized at peak efficiency in order to benefit humanity with the most advanced scientific knowledge. In order to attain this level of efficiency, the materials which make up these electronics, or possibly more important, the fundamental characteristics of these materials, must be fully understood. The following research attempted to uncover the properties and characteristics of a selected family of materials. Herein, zinc …

Photocatalytic Reduction Of Co2 With Tunable Bandgap And Bandedge Materials, Thuhuong T. Ngo

USF Tampa Graduate Theses and Dissertations

Solar energy is a sustainable resource which has substantial potential to meet the increasing demand for renewable energy. Though there has been some success in harvesting solar energy for electricity production, converting solar energy to chemical energy as fuels is still a challenge due to low efficiency.

Since the discovery of TiO₂ photocatalysts for splitting water (4) and reducing CO₂ (5) to form useful chemical feedstock such as H₂, CO and CH₄, much research has been done to increase the efficiency of photocatalysts. However, the current conversion efficiency of photocatalysts remains low (~5%) (6, …

Optimal Demand Response Models With Energy Storage Systems In Smart Grids, Mohemmed Masooud Alhaider

USF Tampa Graduate Theses and Dissertations

This research aims to develop solutions to relieve system stress conditions in electric grids. The approach adopted in this research is based on a new concept in the Smart Grid, namely, demand response optimization. A number of demand response programs with energy storage systems are designed to enable a community to achieve optimal demand side energy management.

The proposed models aim to improve the utilization of the demand side energy through load management programs including peak shaving, load shifting, and valley lling. First, a model is proposed to nd the optimal capacity of the battery energy storage system (BESS) to …

Searching Neuroimaging Biomarkers In Mental Disorders With Graph And Multimodal Fusion Analysis Of Functional Connectivity, Hao He

Electrical and Computer Engineering ETDs

Mental disorders such as schizophrenia (SZ), bipolar (BD), and major depression disorders (MDD) can cause severe symptoms and life disruption. They share some symptoms, which can pose a major clinical challenge to their differentiation. Objective biomarkers based on neuroimaging may help to improve diagnostic accuracy and facilitate optimal treatment for patients. Over the last decades, non-invasive in-vivo neuroimaging techniques such as magnetic resonance imaging (MRI) have been increasingly applied to measure structure and function in human brains. With functional MRI (fMRI) or structural MRI (sMRI), studies have identified neurophysiological deficits in patients’ brain from different perspective. Functional connectivity (FC) analysis …

Experimental Investigation Of Plasma Dynamics In Jets And Bubbles Using A Compact Coaxial Plasma Gun In A Background Magnetized Plasma, Yue Zhang

Electrical and Computer Engineering ETDs

Numerous solar and astrophysical observations of jet- and bubble-like plasma structures exhibit morphological similarities, suggesting that there may be common plasma physics at work in the formation and evolution processes of these structures at different system scales. The ideal magnetohydrodynamics (MHD) provide the necessary theoretical basis for employing laboratory experiments to investigate key physical processes in nonlinear astrophysical and solar systems, especially when magnetic fields are present.

A coaxial magnetized plasma gun has been designed, installed, and operated in the HelCat linear device at the University of New Mexico. In Region I, a current-driven plasma jet is formed. The plasma …

Intrinsic Functions For Securing Cmos Computation: Variability, Modeling And Noise Sensitivity, Xiaolin Xu

Doctoral Dissertations

A basic premise behind modern secure computation is the demand for lightweight cryptographic primitives, like identifier or key generator. From a circuit perspective, the development of cryptographic modules has also been driven by the aggressive scalability of complementary metal-oxide-semiconductor (CMOS) technology. While advancing into nano-meter regime, one significant characteristic of today's CMOS design is the random nature of process variability, which limits the nominal circuit design. With the continuous scaling of CMOS technology, instead of mitigating the physical variability, leveraging such properties becomes a promising way. One of the famous products adhering to this double-edged sword philosophy is the Physically …

High Power Optically Pumped Semiconductor Lasers For Sodium Guidestar Applications, Shawn W. Hackett

Optical Science and Engineering ETDs

Optically pumped semiconductor lasers (OPSLs) are shown to provide a much more compact and less expensive source for illumination of the sodium layer of the mesosphere for use as a sodium laser guidestar via single and two photon excitation schemes. This represents a revolution in laser guidestar technology as the cost, size, and power requirements for a laser guidestar system are shown to have been decreased by an order of magnitude with guidestar performance shown to be similar to previous sources. Sodium laser guidestar sources for broadband simultaneous illumination of multiple lines are developed and simulated. Simulations are then compared …

Automatic Fracture Orientation Extraction From Sfm Point Clouds, Jon Kissi

Electronic Thesis and Dissertation Repository

Geology seeks to understand the history of the Earth and its surface processes through charac- terisation of surface formations and rock units. Chief among the geologists’ tools are rock unit orientation measurements, such as Strike, Dip and Dip Direction. These allow an understanding of both surface and sub-structure on both the local and macro scale.

Although the way these techniques can be used to characterise geology are well understood, the need to collect these measurements by hand adds time and expense to the work of the geologist, precludes spontaneity in field work, and coverage is limited to where the geologist …

Performance-Robust Dynamic Feedback Control Of Lipschitz Nonlinear Systems, Winston Baker

Dissertations (1934 -)

This dissertation addresses the dynamic control of nonlinear systems with finite energy noise in the state and measurement equations. Regional eigenvalue assignment (REA) is used to ensure that the state estimate error is driven to zero significantly faster than the state itself. Moreover, the controller is designed for the resulting closed loop system to achieve any one of a set of general performance criteria (GPC). The nonlinear model is assumed to have a Lipschitz nonlinearity both in the state and measurement equations. By using the norm bound of the nonlinearity, the controller is designed to be robust against all nonlinearities …

Physical Layer Defenses Against Primary User Emulation Attacks, Joan A. Betances

Theses and Dissertations

Cognitive Radio (CR) is a promising technology that works by detecting unused parts of the spectrum and automatically reconfiguring the communication system's parameters in order to operate in the available communication channels while minimizing interference. CR enables efficient use of the Radio Frequency (RF) spectrum by generating waveforms that can coexist with existing users in licensed spectrum bands. Spectrum sensing is one of the most important components of CR systems because it provides awareness of its operating environment, as well as detecting the presence of primary (licensed) users of the spectrum.

Collective Contextual Anomaly Detection For Building Energy Consumption, Daniel Berhane Araya

Electronic Thesis and Dissertation Repository

Commercial and residential buildings are responsible for a substantial portion of total global energy consumption and as a result make a significant contribution to global carbon emissions. Hence, energy-saving goals that target buildings can have a major impact in reducing environmental damage. During building operation, a significant amount of energy is wasted due to equipment and human-related faults. To reduce waste, today's smart buildings monitor energy usage with the aim of identifying abnormal consumption behaviour and notifying the building manager to implement appropriate energy-saving procedures. To this end, this research proposes the \textit{ensemble anomaly detection} (EAD) framework. The EAD is …

The Influence Of The Electric Supply Industry On Economic Growth In Less Developed Countries, Edward Richard Bee

Dissertations

This study measures the impact that electrical outages have on manufacturing production in 135 less developed countries using stochastic frontier analysis and data from World Bank’s Investment Climate surveys. Outages of electricity, for firms with and without backup power sources, are the most frequently cited constraint on manufacturing growth in these surveys.

Outages are shown to reduce output below the production frontier by almost five percent in Africa and by a lower percentage in South Asia, Southeast Asia and the Middle East and North Africa. Production response to outages is quadratic in form. Outages also increase labor cost, reduce exports …

Nanophotonics For Dark Materials, Filters, And Optical Magnetism, Mengren Man

Open Access Dissertations

Research on nanophotonic structures for three application areas is described, a near perfect optical absorber based on a graphene/dielectric stack, an ultraviolet bandpass filter formed with an aluminum/dielectric stack, and structures exhibiting homogenizable magnetic properties at infrared frequencies. The graphene stack can be treated as a effective, homogenized medium that can be designed to reflect little light and absorb an astoundingly high amount per unit thickness, making it an ideal dark material and providing a new avenue for photonic devices based on two-dimensional materials. Another material stack arrangement with thin layers of metal and insulator forms a multi-cavity filter that …

Exploring Spin-Transfer-Torque Devices And Memristors For Logic And Memory Applications, Zoha Pajouhi

Open Access Dissertations

As scaling CMOS devices is approaching its physical limits, researchers have begun exploring newer devices and architectures to replace CMOS.

Due to their non-volatility and high density, Spin Transfer Torque (STT) devices are among the most prominent candidates for logic and memory applications. In this research, we first considered a new logic style called All Spin Logic (ASL). Despite its advantages, ASL consumes a large amount of static power; thus, several optimizations can be performed to address this issue. We developed a systematic methodology to perform the optimizations to ensure stable operation of ASL.

Second, we investigated reliable design of …

An Energy Efficient, Load Balancing, And Reliable Routing Protocol For Wireless Sensor Networks, Kamil Samara

Theses and Dissertations

AN ENERGY EFFICIENT, LOAD BALANCING, AND RELIABLE ROUTING PROTOCOL FOR WIRELESS SENSOR NETWORKS

by

Kamil Samara

The University of Wisconsin-Milwaukee, 2016

Under the Supervision of Professor Hossein Hosseini

The Internet of Things (IoT) is shaping the future of Computer Networks and Computing in general, and it is gaining ground very rapidly. The whole idea has originated from the pervasive presence of a variety of things or objects equipped with the internet connectivity. These devices are becoming cheap and ubiquitous, at the same time more powerful and smaller with a variety of onboard sensors. All these factors with the availability of …

Transient Control Of Synchronous Machine Active And Reactive Power In Micro-Grid Power Systems, Luke Gerard Weber

Theses and Dissertations

There are two main topics associated with this dissertation. The first is to investigate

phase–to–neutral fault current magnitude occurring in generators with multiple zero–sequence

current sources. The second is to design, model, and tune a linear control system for oper-

ating a micro–grid in the event of a separation from the electric power system.

In the former case, detailed generator, AC8B excitation system, and four–wire electric

power system models are constructed. Where available, manufacturers data is used to

validate the generator and exciter models. A gain–delay with frequency droop control

is used to model an internal combustion engine and governor. …

A Haptic Surface Robot Interface For Large-Format Touchscreen Displays, Mark Price

Masters Theses

This thesis presents the design for a novel haptic interface for large-format touchscreens. Techniques such as electrovibration, ultrasonic vibration, and external braked devices have been developed by other researchers to deliver haptic feedback to touchscreen users. However, these methods do not address the need for spatial constraints that only restrict user motion in the direction of the constraint. This technology gap contributes to the lack of haptic technology available for touchscreen-based upper-limb rehabilitation, despite the prevalent use of haptics in other forms of robotic rehabilitation. The goal of this thesis is to display kinesthetic haptic constraints to the touchscreen user …

An Interactive Likelihood For The Multi-Bernoulli Filter, Anthony B. Hoak

Master's Theses (2009 -)

In this thesis, a simple yet effective technique is presented for increasing the accuracy of multi-target tracking algorithms with a focus on sequential Monte-Carlo implementations of random finite set-based approaches. This technique, referred to throughout this work as an interactive likelihood, exploits the spatial information that exists in any given measurement, reducing the need for data association and allowing for more target interaction thereby increasing overall tracking accuracy. The interactive likelihood is constructed entirely within the random finite set framework and is integrated with a multi-Bernoulli filter. In addition, a state-of-the-art deep neural network for pedestrian detection is combined in …

Vector Beams For Fundamental Physics And Applications, Giovanni Milione

Dissertations, Theses, and Capstone Projects

Lights salient degrees of freedom are the independent parameters that completely de- scribe an electromagnetic wave (in the paraxial approximation) and include polarization, wavelength, and time. Most recently, lights space degree of freedom has received sig- nificant attention via the sub-discipline of optics that can be referred to as complex light or structured light. The study of complex light is a veritable renaissance of optics; us- ing lights space degree of freedom many classical optics phenomena have been revisited with novel results. In this thesis, a novel form of structured light referred to as vector beams will be investigated. It …

Musictrakr, Benjamin Lin

Computer Engineering

MusicTrackr is an IoT device that musicians attach to their instruments. The device has a start and stop button that allows users to record their playing sessions. Each recorded session is sent wirelessly to a cloud database. An accompanying website displays all of the recorded sessions, organized by date. After picking a specific date, the user can view graphs showing total practice time and average session length as well play back any recordings during that date. In addition, the user may add comments to any specific date or recording. Lastly, the user may tag a specific date with a color …

Prosense, Johnny Favazza Ii, Casey Glasgow, Matt Epperson

Computer Engineering

This project aims to gather advanced data sets from MEMS sensors and GPS and deliver it to the user, who can capitalize on the data. The once negligible half-degree difference of your board barreling down a wave can be recorded from a gyro and exploited for the perfect turn. The exact speed dreaded by longboarders where speed wobbles turn into a road rash can be analysed and consequently avoided. Ascertaining the summit of your flight using combined GPS sensors from the ski ramp allows for the correct timing of tricks. When it comes to pursuing excellence in professional sports, amateur …

A Graph Based Departmental Spoken Dialogue System, Julia Isaac

Honors Theses

Spoken dialogue systems are automatic, computer based systems that are a great way for people to receive important information. In this project, I created a spoken dialogue system that people can use to learn about the Computer Science Department at Union College. The system was built by populating an open source dialogue system using a graph based dialogue manager. I improved upon a previous working dialogue system by making the conversations sound more natural, improving the flexibility of the system and making the system more robust. To help with this process a corpus was created using about 200 different dialogues …

Processing Of Simulated And Experimental Images Of Closely Spaced Binary Stars Using Speckle Interferometry, Niels Smidth

Master's Theses

Theory and methods of processing speckle interferometry data from close visual binary stars are presented and implemented. The effects of the optical systems used for observing close visual binary stars are explained and simulated from both the geometrical and physical optical viewpoints. The atmospheric phase distortion and shot noise responsible for the observed speckle patterns are simulated. The deconvolution technique originally presented by Labeyrie is implemented to extract astrometric data from close visual binary stars. This method is applied to both simulated and experimental data from Kitt Peak National Observatory as validation. Parts of the deconvolution process are optimized to …

The Effects Of Phosphonic Acids In Dye-Sensitized Solar Cells, Keith Edward James

Dissertations and Theses

Novel methods for the construction of dye-sensitized solar cells (DSSCs) were developed. A thin dense underlayer of TiO₂ was applied on fluorine-doped tin oxide (FTO) glass using as a precursor Tyzor AA-105. Subsequently a mesoporous film of P-25 TiO₂ was applied by spreading a suspension uniformly over the surface of the underlayer and allowing the plate to slowly dry while resting on a level surface. After sintering at 500° C slides were treated with TCPP as a sensitizing dye and assembled into DSSCs. A novel method was used to seal the cells; strips of Parafilm® were used as …