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Assessing The Viability Of Sol-Gel Nimgo Films For Solar Blind Detection, Amber Scheurer
Assessing The Viability Of Sol-Gel Nimgo Films For Solar Blind Detection, Amber Scheurer
HIM 1990-2015
Wide bandgap semiconductors have been broadly investigated for their potential to detect and emit high energy ultraviolet (UV) photons. Advancements in deep UV optoelectronic materials would enable the efficient and affordable realization of many medical, industrial and consumer UV optical devices. The traditional growth method, vacuum deposition, is an extremely complicated and expensive process. Sol-gel processing dramatically simplifies facility requirements and can be scaled to industrial size. The work presented here involves a novel study of the ternary wide bandgap material Ni1-xMgxO. Films were developed by sol-gel spin coating for investigation of material and electrical properties. This method produced films …
Integration Of High-Q Filters With Highly Efficient Antennas, Yazid Yusuf
Integration Of High-Q Filters With Highly Efficient Antennas, Yazid Yusuf
Electronic Theses and Dissertations
The integration of high-quality (Q)-factor 3-D filters with highly efficient antennas is addressed in this dissertation. Integration of filters and antennas into inseparable units eliminates the transitions between the otherwise separate structures resulting in more compact and efficient systems. The compact, highly efficient integrated 3-D filter/antenna systems, enabled by the techniques developed herein, allow for the realization of integrated RF front ends with significantly- reduced form factors. Integration of cavity filters with slot antennas in a single planar substrate is first demonstrated. Due to the high Q factor of cavity resonators, the efficiency of the integrated filter/antenna system is found …
Analysis Of Behaviors In Crowd Videos, Ramin Mehran
Analysis Of Behaviors In Crowd Videos, Ramin Mehran
Electronic Theses and Dissertations
In this dissertation, we address the problem of discovery and representation of group activity of humans and objects in a variety of scenarios, commonly encountered in vision applications. The overarching goal is to devise a discriminative representation of human motion in social settings, which captures a wide variety of human activities observable in video sequences. Such motion emerges from the collective behavior of individuals and their interactions and is a significant source of information typically employed for applications such as event detection, behavior recognition, and activity recognition. We present new representations of human group motion for static cameras, and propose …
Ultra High Density Spectral Beam Combining By Thermal Tuning Of Volume Bragg Gratings In Photo-Thermo-Refractive Glass, Derrek Drachenberg
Ultra High Density Spectral Beam Combining By Thermal Tuning Of Volume Bragg Gratings In Photo-Thermo-Refractive Glass, Derrek Drachenberg
Electronic Theses and Dissertations
High power lasers with diffraction limited beam quality are desired for many applications in defense and manufacturing. A lot of applications require laser beams at the 100 kW power level along with divergence close to the diffraction limit. The figure of merit for a beam used in such applications should be radiance which determines the laser power delivered to a remote target. One of the primary limiting factors is thermal distortion of a laser beam caused by excessive heat generated in the laser media. Combination of multiple laser beams is usually considered as a method to mitigate these limitations. Spectral …
Theoretical Study Of Beam Transformations By Volume Diffraction, Sergiy V. Mokhov
Theoretical Study Of Beam Transformations By Volume Diffraction, Sergiy V. Mokhov
Electronic Theses and Dissertations
Laser beams can be manipulated by volume diffractive elements in addition to conventional optical elements like mirrors, lenses, and beam splitters. Conventional optical elements can be described by applying the basic laws of reflection and refraction at the surfaces of the elements. Even diffraction by surface gratings utilizes relatively simple mathematics. This is to be contrasted with the volume diffraction, which requires coupled wave theory in the slowly varying envelope approximation (SVEA) to obtain accurate results. Efficient spatially distributed diffraction of laser beams is possible due to the high coherence of laser light, and it occurs at specific resonant Bragg …
Characterization Of The Nonlinear Refractive Index Of Carbon Disulfide Over An Extended Spectral And Temporal Range, Marcus Seidel
Characterization Of The Nonlinear Refractive Index Of Carbon Disulfide Over An Extended Spectral And Temporal Range, Marcus Seidel
Electronic Theses and Dissertations
The intensity dependent refractive index change of a medium is frequently described in terms of the product n₂ · I where n₂ is the nonlinear refractive index and I the light intensity. The nonlinear refractive index is often treated as constant which is a reasonable assumption if the light interacts only with bound electrons. In the case of carbon disulfide (CS₂) however, nuclear motions contribute to n₂. These motions occur on the sub picosecond time scale and thus become especially relevant for ultrashort laser pulses. The neat liquid CS₂ is studied because it exhibits a large nonlinear refractive index in …
Investigation And Trade Study On Hot Carrier Reliability Of The Phemt For Dc And Rf Performance, Jason Steighner
Investigation And Trade Study On Hot Carrier Reliability Of The Phemt For Dc And Rf Performance, Jason Steighner
Electronic Theses and Dissertations
A unified study on the hot carrier reliability of the Pseudomorphic High Electron Mobility Transistor (PHEMT) is carried out through Sentaurus Device Simulation, measurement, and physical analyses. A trade study of devices with four various geometries are evaluated for DC and RF performance. The trade-off of DC I-V characteristics, transconductance, and RF parameters versus hot carrier induced gate current is assessed for each device. Ambient temperature variation is also evaluated to observe its impact on hot carrier effects. A commercial grade PHEMT is then evaluated and measured to demonstrate the performance degradation that occurs after a period of operation in …
Nonlinear Estimation And Control For Assistive Robots, Zhao Wang
Nonlinear Estimation And Control For Assistive Robots, Zhao Wang
Electronic Theses and Dissertations
In this thesis, we document the progress in the estimation and control design of a smart assistive robot arm that can provide assistance during activities of daily living to the elderly and/or users with disabilities. Interaction with the environment is made challenging by the kinematic uncertainty in the robot, imperfect sensor calibration, limited view of angle as well as the fact that most activities of daily living are generally required to be performed in unstructured environments. For monocular visual systems, range (or depth) information is always crucial for target modeling and system control design. In the first part of my …
Exploring Techniques For Measurement And Improvement Of Data Quality With Application To Determination Of The Last Known Position (Lkp) In Search And Rescue (Sar) Data, Abhijit Wakchaure
Exploring Techniques For Measurement And Improvement Of Data Quality With Application To Determination Of The Last Known Position (Lkp) In Search And Rescue (Sar) Data, Abhijit Wakchaure
Electronic Theses and Dissertations
There is a tremendous volume of data being generated in today’s world. As organizations around the globe realize the increased importance of their data as being a valuable asset in gaining a competitive edge in a fast-paced and a dynamic business world, more and more attention is being paid to the quality of the data. Advances in the fields of data mining, predictive modeling, text mining, web mining, business intelligence, health care analytics, etc. all depend on clean, accurate data. That one cannot effectively mine data, which is dirty, comes as no surprise. This research is an exploratory study of …
Exploiting Opponent Modeling For Learning In Multi-Agent Adversarial Games, Kennard R. Laviers
Exploiting Opponent Modeling For Learning In Multi-Agent Adversarial Games, Kennard R. Laviers
Electronic Theses and Dissertations
An issue with learning effective policies in multi-agent adversarial games is that the size of the search space can be prohibitively large when the actions of both teammates and opponents are considered simultaneously. Opponent modeling, predicting an opponent’s actions in advance of execution, is one approach for selecting actions in adversarial settings, but it is often performed in an ad hoc way. In this dissertation, we introduce several methods for using opponent modeling, in the form of predictions about the players’ physical movements, to learn team policies. To explore the problem of decision-making in multi-agent adversarial scenarios, we use our …
Perceptual Image Quality Of Launch Vehicle Imaging Telescopes, Joshua K. Lentz
Perceptual Image Quality Of Launch Vehicle Imaging Telescopes, Joshua K. Lentz
Electronic Theses and Dissertations
A large fleet (in the hundreds) of high quality telescopes are used for tracking and imaging of launch vehicles during ascent from Cape Canaveral Air Force Station and Kennedy Space Center. A maintenance tool has been development for use with these telescopes. The tool requires rankings of telescope condition in terms of the ability to generate useful imagery. It is thus a case of ranking telescope conditions on the basis of the perceptual image quality of their imagery. Perceptual image quality metrics that are well-correlated to observer opinions of image quality have been available for several decades. However, these are …
Feature Pruning For Action Recognition In Complex Environment, Adarsh Nagaraja
Feature Pruning For Action Recognition In Complex Environment, Adarsh Nagaraja
Electronic Theses and Dissertations
A significant number of action recognition research efforts use spatio-temporal interest point detectors for feature extraction. Although the extracted features provide useful information for recognizing actions, a significant number of them contain irrelevant motion and background clutter. In many cases, the extracted features are included as is in the classification pipeline, and sophisticated noise removal techniques are subsequently used to alleviate their effect on classification. We introduce a new action database, created from the Weizmann database, that reveals a significant weakness in systems based on popular cuboid descriptors. Experiments show that introducing complex backgrounds, stationary or dynamic, into the video …
Class F And Inverse Class F Power Amplifier Subject To Electrical Stress Effect, Giji Skaria
Class F And Inverse Class F Power Amplifier Subject To Electrical Stress Effect, Giji Skaria
Electronic Theses and Dissertations
This study investigated the Class F and inverse Class F RF power amplifier operating at 5.8 GHz. The major challenging issue in design and implementation of CMOS power transistor is the breakdown voltage especially in sub-micron CMOS technologies. In order to eliminate this problem a Cascode topologies were implemented to reduce the Drain-toSource voltage (stress). A Cascode Class F & Inverse Class F RF power amplifier were designed, and optimized in order to improve efficiency and reliability using 0.18µm CMOS technology process. A 50% decrease in the stress has been achieved in the Cascode class-F and Inverse class F amplifiers. …
Spectrum Sharing And Service Pricing In Dynamic Spectrum Access Networks, Swastik Kumar Brahma
Spectrum Sharing And Service Pricing In Dynamic Spectrum Access Networks, Swastik Kumar Brahma
Electronic Theses and Dissertations
Traditionally, radio spectrum has been statically allocated to wireless service providers (WSPs). Regulators, like FCC, give wireless service providers exclusive long term licenses for using specific range of frequencies in particular geographic areas. Moreover, restrictions are imposed on the technologies to be used and the services to be provided. The lack of flexibility in static spectrum allocation constrains the ability to make use of new technologies and the ability to redeploy the spectrum to higher valued uses, thereby resulting in inefficient spectrum utilization [23, 38, 42, 62, 67]. These limitations have motivated a paradigm shift from static spectrum allocation towards …
Global Secure Sets Of Trees And Grid-Like Graphs, Yiu Yu Ho
Global Secure Sets Of Trees And Grid-Like Graphs, Yiu Yu Ho
Electronic Theses and Dissertations
Let G = (V, E) be a graph and let S ⊆ V be a subset of vertices. The set S is a defensive alliance if for all x ∈ S, |N[x] ∩ S| ≥ |N[x] − S|. The concept of defensive alliances was introduced in [KHH04], primarily for the modeling of nations in times of war, where allied nations are in mutual agreement to join forces if any one of them is attacked. For a vertex x in a defensive alliance, the number of neighbors of x inside the alliance, plus the vertex x, is at least the number …
Modeling, Design And Fabrication Of Orthogonal And Psuedo-Orthogonal Frequency Coded Saw Wireless Spread Spectrum Rfid Sensor Tags, Nancy Saldanha
Modeling, Design And Fabrication Of Orthogonal And Psuedo-Orthogonal Frequency Coded Saw Wireless Spread Spectrum Rfid Sensor Tags, Nancy Saldanha
Electronic Theses and Dissertations
Surface acoustic wave (SAW) sensors offer a wireless, passive sensor solution for use in numerous environments where wired sensing can be expensive and infeasible. Single carrier frequency SAW sensor embodiments such as delay lines, and resonators have been used in single sensor environments where sensor identification is not a necessity. The orthogonal frequency coded (OFC) SAW sensor tag embodiment developed at UCF uses a spread spectrum approach that allows interrogation in a multi-sensor environment and provides simultaneous sensing and sensor identi- fication. The SAW device is encoded via proper design of multiple Bragg reflectors at differing frequencies. To enable accurate …
Few-Cycle Pulses Amplification For Attosecond Science Applications Modeling And Experiments, Michael Hemmer
Few-Cycle Pulses Amplification For Attosecond Science Applications Modeling And Experiments, Michael Hemmer
Electronic Theses and Dissertations
The emergence of mode-locked oscillators providing pulses with durations as short as a few electric-field cycles in the near infra-red has paved the way toward electric-field sensitive physics experiments. In addition, the control of the relative phase between the carrier and the pulse envelope, developed in the early 2000’s and rewarded by a Nobel price in 2005, now provides unprecedented control over the pulse behaviour. The amplification of such pulses to the millijoule level has been an on-going task in a few world-class laboratories and has triggered the dawn of attoscience, the science of events happening on an attosecond timescale. …
A Radar Interrogator For Wireless Passive Temperature Sensing, Jeffrey Charles Lambert
A Radar Interrogator For Wireless Passive Temperature Sensing, Jeffrey Charles Lambert
Electronic Theses and Dissertations
In this thesis I explore radio detection and ranging (RADAR) and software defined radio (SDR) in the context of wireless passive sensor interrogation. A RADAR topology is selected based upon preliminary measurements using ordinary laboratory instrumentation and then used for construction of a prototype X-band wireless measurement system using commercial, off-theshelf (COTS) components. This research explores the feasibility of wireless passive sensor interrogation through practical application of SDR and RADAR techniques to the interrogation of a wireless passive resonator signal. This work serves as a foundation for further research on sensor interrogation through establishment of critical system parameters in the …
Cmos Rf Cituits Sic] Variability And Reliability Resilient Design, Modeling, And Simulation, Yidong Liu
Cmos Rf Cituits Sic] Variability And Reliability Resilient Design, Modeling, And Simulation, Yidong Liu
Electronic Theses and Dissertations
The work presents a novel voltage biasing design that helps the CMOS RF circuits resilient to variability and reliability. The biasing scheme provides resilience through the threshold voltage (VT) adjustment, and at the mean time it does not degrade the PA performance. Analytical equations are established for sensitivity of the resilient biasing under various scenarios. Power Amplifier (PA) and Low Noise Amplifier (LNA) are investigated case by case through modeling and experiment. PTM 65nm technology is adopted in modeling the transistors within these RF blocks. A traditional class-AB PA with resilient design is compared the same PA without such design …
Spatio-Temporal Negotiation Protocols, Yi Luo
Spatio-Temporal Negotiation Protocols, Yi Luo
Electronic Theses and Dissertations
Canonical problems are simplified representations of a class of real world problems. They allow researchers to compare algorithms in a standard setting which captures the most important challenges of the real world problems being modeled. In this dissertation, we focus on negotiating a collaboration in space and time, a problem with many important real world applications. Although technically a multi-issue negotiation, we show that the problem can not be represented in a satisfactory manner by previous models. We propose the "Children in the Rectangular Forest" (CRF) model as a possible canonical problem for negotiating spatio-temporal collaboration. In the CRF problem, …
Wirelessly Sensing Resonate Frequency Of Passive Resonators With Different Q Values, Mathew Walter Lukacs
Wirelessly Sensing Resonate Frequency Of Passive Resonators With Different Q Values, Mathew Walter Lukacs
Electronic Theses and Dissertations
Numerous techniques exist for measuring temperature using passive devices such as SAW filters. However, SAW filters have a significant limitation regarding high temperature environments exceeding 1000⁰C [1]. There are several applications for a high temperature sensor in this range, most notably heat flux or temperature in turbine engines. For these environments, an alternative to SAW filters is to use a passive resonator. The resonate frequency will vary depending on the environment temperature. Understanding how the frequency changes with temperature will allow us to determine the environmental temperature. In order for this approach to work, it is necessary to induce resonance …
Rain Rate Retrieval Algorithm For Aquarius/Sac-D Microwave Radiometer, Rosa Ana Menzerotolo
Rain Rate Retrieval Algorithm For Aquarius/Sac-D Microwave Radiometer, Rosa Ana Menzerotolo
Electronic Theses and Dissertations
Microwave radiometers are used to measure blackbody microwave emissions emitted by natural targets. Radiative transfer theory provides a well founded physical relationship between the atmosphere and surface geophysical parameters and the brightness temperature measured by these radiometers. The atmospheric brightness temperature is proportional to the integral of the microwave absorption of water vapor, oxygen, and liquid water between the top of the atmosphere and the surface. Inverse radiative transfer models use to retrieve the water vapor, cloud liquid and oxygen content in the atmosphere are very well known; however, the retrieval of rain rate in the atmosphere is still a …
Design, Fabrication, And Testing Of High-Transparency Deep Ultra-Violet Contacts Using Surface Plasmon Coupling In Subwavelength Aluminum Meshes, Clarisse Mazuir
Design, Fabrication, And Testing Of High-Transparency Deep Ultra-Violet Contacts Using Surface Plasmon Coupling In Subwavelength Aluminum Meshes, Clarisse Mazuir
Electronic Theses and Dissertations
The present work aims at enhancing the external quantum efficiencies of ultra-violet (UV) sensitive photodetectors (PDs) and light emitting diodes (LEDs)for any light polarization. Deep UV solid state devices are made out of AlGaN or MgZnO and their performances suffer from the high resistivity of their p-doped regions. They require transparent p-contacts; yet the most commonly used transparent contacts have low transmission in the UV: indium tin oxide (ITO) and nickel-gold (Ni/Au 5/5 nms) transmit less than 50% and 30% respectively at 300 nm. Here we investigate the use of surface plasmons (SPs) to design transparent p-contacts for AlGaN devices …
Design And Operation Of Stationary Distributed Battery Micro-Storage Systems, Ala R. Al-Haj Hussein
Design And Operation Of Stationary Distributed Battery Micro-Storage Systems, Ala R. Al-Haj Hussein
Electronic Theses and Dissertations
Due to some technical and environmental constraints, expanding the current electric power generation and transmission system is being challenged by even increasing the deployment of distributed renewable generation and storage systems. Energy storage can be used to store energy from utility during low-demand (off-peak) hours and deliver this energy back to the utility during high-demand (on-peak) hours. Furthermore, energy storage can be used with renewable sources to overcome some of their limitations such as their strong dependence on the weather conditions, which cannot be perfectly predicted, and their unmatched or out-of-synchronization generation peaks with the demand peaks. Generally, energy storage …
Multilayered Planar Periodic Subwavelength Microstructures For Generating And Detecting Circularly Polarized Thermal Infrared Radiation, Samuel Lanning Wadsworth
Multilayered Planar Periodic Subwavelength Microstructures For Generating And Detecting Circularly Polarized Thermal Infrared Radiation, Samuel Lanning Wadsworth
Electronic Theses and Dissertations
Generation and detection of circularly-polarized (CP) radiation in the 8- to 12-μm band of the infrared (IR) spectrum is crucial for polarization sensing and imaging scenarios. There is very little naturally occurring CP radiation in the long-wave IR band, so that useful functionalities may be obtained by exploiting preferential radiation and transmission characteristics of engineered metamaterials. Conventional CP devices in the IR utilize birefringent crystals, which are typically bulky and expensive to manufacture. The operation of these devices is generally optimized at a single wavelength. Imaging in the long-wave IR is most often broadband, so that achromatic CP-device behavior is …
Reliability Study Of Ingap/Gaas Heterojunction Bipolar Transistor Mmic Technology By Characterization, Modeling And Simulation, Xiang Liu
Electronic Theses and Dissertations
Recent years have shown real advances of microwave monolithic integrated circuits (MMICs) for millimeter-wave frequency systems, such as wireless communication, advanced imaging, remote sensing and automotive radar systems, as MMICs can provide the size, weight and performance required for these systems. Traditionally, GaAs pseudomorphic high electron mobility transistor (pHEMT) or InP based MMIC technology has dominated in millimeter-wave frequency applications because of their high fT and fmax as well as their superior noise performance. But these technologies are very expensive. Thus, for low cost and high performance applications, InGaP/GaAs heterojunction bipolar transistors (HBTs) are quickly becoming the preferred technology to …
The Performance And Power Impact Of Using Multiple Dram Address Mapping Schemes In Multicore Processors, Rami Jadaa
The Performance And Power Impact Of Using Multiple Dram Address Mapping Schemes In Multicore Processors, Rami Jadaa
Electronic Theses and Dissertations
Lowest-level cache misses are satisfied by the main memory through a specific address mapping scheme that is hard-coded in the memory controller. A dynamic address mapping scheme technique is investigated to provide higher performance and lower power consumption, and a method to throttle memory to meet a specific power budget. Several experiments are conducted on single and multithreaded synthetic memory traces -to study extreme cases- and validate the usability of the proposed dynamic mapping scheme over the fixed one. Results show that applications’ performance varies according to the mapping scheme used, and a dynamic mapping scheme achieves up to 2x …
Electromagnetic Propagation Anomalies In Waveguiding Structures And Scattering Systems, Alessandro Salandrino
Electromagnetic Propagation Anomalies In Waveguiding Structures And Scattering Systems, Alessandro Salandrino
Electronic Theses and Dissertations
The effects related to diffraction and interference are ubiquitous in phenomena involving electromagnetic wave propagation, and are accurately predicted and described within the framework of classical electrodynamics. In the vast majority of the cases the qualitative features of the evolution of a propagating wave can be inferred even without detailed calculations. A field distribution will spread upon propagation, will accumulate phase along the direction of power flow, will exert mechanical forces upon scattering objects in the direction of propagation etc. When such predictions fail, counterintuitive effects and new functionalities can be engineered. In this work a series of exceptional cases …
Lyapunov-Based Control Design For Uncertain Mimo Systems, Zhao Wang
Lyapunov-Based Control Design For Uncertain Mimo Systems, Zhao Wang
Electronic Theses and Dissertations
In this dissertation. we document the progress in the control design for a class of MIMO nonlinear uncertain system from five papers. In the first part, we address the problem of adaptive control design for a class of multi-input multi-output (MIMO) nonlinear systems. A Lypaunov based singularity free control law, which compensates for parametric uncertainty in both the drift vector and the input gain matrix, is proposed under the mild assumption that the signs of the leading minors of the control input gain matrix are known. Lyapunov analysis shows global uniform ultimate boundedness (GUUB) result for the tracking error under …
Data-True Characterization Of Neuronal Models, Jose Suarez
Data-True Characterization Of Neuronal Models, Jose Suarez
Electronic Theses and Dissertations
In this thesis, a weighted least squares approach is initially presented to estimate the parameters of an adaptive quadratic neuronal model. By casting the discontinuities in the state variables at the spiking instants as an impulse train driving the system dynamics, the neuronal output is represented as a linearly parameterized model that depends on filtered versions of the input current and the output voltage at the cell membrane. A prediction errorbased weighted least squares method is formulated for the model. This method allows for rapid estimation of model parameters under a persistently exciting input current injection. Simulation results show the …