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Full-Text Articles in Engineering

Psychophysiological Analysis Of A Pedagogical Agent And Robotic Peer For Individuals With Autism Spectrum Disorders., Mohammad Nasser Saadatzi Dec 2016

Psychophysiological Analysis Of A Pedagogical Agent And Robotic Peer For Individuals With Autism Spectrum Disorders., Mohammad Nasser Saadatzi

Electronic Theses and Dissertations

Autism spectrum disorder (ASD) is a neurodevelopmental disorder characterized by ongoing problems in social interaction and communication, and engagement in repetitive behaviors. According to Centers for Disease Control and Prevention, an estimated 1 in 68 children in the United States has ASD. Mounting evidence shows that many of these individuals display an interest in social interaction with computers and robots and, in general, feel comfortable spending time in such environments. It is known that the subtlety and unpredictability of people’s social behavior are intimidating and confusing for many individuals with ASD. Computerized learning environments and robots, however, prepare a predictable, …


Osem : Occupant-Specific Energy Monitoring., Anand S. Kulkarni Aug 2016

Osem : Occupant-Specific Energy Monitoring., Anand S. Kulkarni

Electronic Theses and Dissertations

Electricity has become prevalent in modern day lives. Almost all the comforts people enjoy today, like home heating and cooling, indoor and outdoor lighting, computers, home and office appliances, depend on electricity. Moreover, the demand for electricity is increasing across the globe. The increasing demand for electricity and the increased awareness about carbon footprints have raised interest in the implementation of energy efficiency measures. A feasible remedy to conserve energy is to provide energy consumption feedback. This approach has suggested the possibility of considerable reduction in the energy consumption, which is in the range of 3.8% to 12%. Currently, research …


High Average Power Nanosecond Pulsed Tm:Fiber Laser For Pumping An Optical Parametric Oscillator, Ali Abdulfattah Jan 2016

High Average Power Nanosecond Pulsed Tm:Fiber Laser For Pumping An Optical Parametric Oscillator, Ali Abdulfattah

Electronic Theses and Dissertations

Thulium-doped fiber lasers operating with wavelengths in the vicinity of 2 µm are useful for several emerging applications including generating mid-IR light via nonlinear frequency conversion. In this study we describe the design and construction of a thulium fiber laser system comprising a master oscillator and a power amplifier. The first stage is a Q-switched, thulium-doped photonic crystal fiber oscillator utilizing an acousto-optic modulator to produce 65-80 nanosecond pulses. A diffraction grating in the cavity provides wavelength tunability from 1.8 – 2µm. The oscillator produced up to 3 W of average power and 150 µJ pulse energies, corresponding to 2.3 …


Smart Grasping Using Laser And Tactile Array Sensors For Ucf-Manus- An Intelligent Assistive Robotic Manipulator, Kiran Prakash Jan 2016

Smart Grasping Using Laser And Tactile Array Sensors For Ucf-Manus- An Intelligent Assistive Robotic Manipulator, Kiran Prakash

Electronic Theses and Dissertations

This thesis presents three improvements in the UCF MANUS Assistive Robotic Manipulator's grasping abilities. Firstly, the robot can now grasp objects that are deformable, heavy and have uneven contact surfaces without undergoing slippage during robotic operations, e.g. paper cup, filled water bottle. This is achieved by installing a high precision non-contacting Laser sensor1 that runs with an algorithm that processes raw-input data from the sensor, registers smallest variation in the relative position of the object with respect to the gripper. Secondly, the robot can grasp objects that are as light and small as single cereal grain without deforming it. To …


Microgrid Control And Protection: Stability And Security, Morteza Keshavarztalebi Jan 2016

Microgrid Control And Protection: Stability And Security, Morteza Keshavarztalebi

Electronic Theses and Dissertations

When the microgrid disconnects from the main grid in response to, say, upstream disturbance or voltage fluctuation and goes to islanding mode, both voltage and frequency at all locations in the microgrid have to be regulated to nominal values in a short amount of time before the operation of protective relays. Motivated by this, we studied the application of intelligent pinning of distributed cooperative secondary control of distributed generators in islanded microgrid operation in a power system. In the first part, the problem of single and multi-pinning of distributed cooperative secondary control of DGs in a microgrid is formulated. It …


Design And Characterization Of System Level Electrostatic Discharge (Esd) Protection Solutions, Yunfeng Xi Jan 2016

Design And Characterization Of System Level Electrostatic Discharge (Esd) Protection Solutions, Yunfeng Xi

Electronic Theses and Dissertations

Electrostatic Discharges (ESD) are one of the main reliability threats in modern electronics. Design, implementation, and characterization of ESD and transient protection of these modern electronics are increasingly challenging due to the process, packaging and cost constraints. Growing communication between ‘objects’ to be sensed and controlled remotely is creating opportunities for greater integration with computer systems, resulting in improved efficiency, accuracy and economic benefits across existing and emerging network infrastructures. This tendency is driving an expansion in data communication as well as industrial applications environment. To keep up with the interconnectivity expansion, the industry requires new devices to support more …


Study Of Novel Power Semiconductor Devices For Performance And Reliability., Karthik Padmanabhan Jan 2016

Study Of Novel Power Semiconductor Devices For Performance And Reliability., Karthik Padmanabhan

Electronic Theses and Dissertations

Power Semiconductor Devices are crucial components in present day power electronic systems. The performance and efficiency of the devices have a direct correlation with the power system efficiency. This dissertation will examine some of the components that are commonly used in a power system, with emphasis on their performance characteristics and reliability. In recent times, there has a proliferation of charge balance devices in high voltage discrete power devices. We examine the same charge balance concept in a fast recovery diode and a MOSFET. This is crucial in the extending system performance at compact dimensions. At smaller device and system …


Investigation Of The Effect Of Rain On Sea Surface Salinity, Andrea Santos Garcia Jan 2016

Investigation Of The Effect Of Rain On Sea Surface Salinity, Andrea Santos Garcia

Electronic Theses and Dissertations

The Aquarius/SAC-D mission provided Sea Surface Salinity (SSS), globally over the ocean, for almost 4 years. As a member of the AQ/SAC-D Cal/Val team, the Central Florida Remote Sensing Laboratory has analyzed these salinity measurements in the presence of precipitation and has noted the high correlation between the spatial patterns of reduced SSS and the spatial distribution of rain. It was determined that this is the result of a cause and effect relation, and not SSS measurement errors. Thus, it is important to understand these salinity changes due to seawater dilution by rain and the associated near-surface salinity strati?cation. This …


Rf Circuit Designs For Reliability And Process Variability Resilience, Ekavut Kritchanchai Jan 2016

Rf Circuit Designs For Reliability And Process Variability Resilience, Ekavut Kritchanchai

Electronic Theses and Dissertations

Complementary metal oxide semiconductor (CMOS) radio frequency (RF) circuit design has been an ever-lasting research field. It has gained so much attention since RF circuits offer high mobility and wide-band efficiency, while CMOS technology provides the advantage of low cost and high integration capability. At the same time, CMOS device size continues to scale to the nanometer regime. Reliability issues with RF circuits have become more challenging than ever before. Reliability mechanisms, such as gate oxide breakdown, hot carrier injection, negative bias temperature instability, have been amplified as the device size shrinks. In addition, process variability becomes a new design …


Model Selection Via Racing, Tiantian Zhang Jan 2016

Model Selection Via Racing, Tiantian Zhang

Electronic Theses and Dissertations

Model Selection (MS) is an important aspect of machine learning, as necessitated by the No Free Lunch theorem. Briefly speaking, the task of MS is to identify a subset of models that are optimal in terms of pre-selected optimization criteria. There are many practical applications of MS, such as model parameter tuning, personalized recommendations, A/B testing, etc. Lately, some MS research has focused on trading off exactness of the optimization with somewhat alleviating the computational burden entailed. Recent attempts along this line include metaheuristics optimization, local search-based approaches, sequential model-based methods, portfolio algorithm approaches, and multi-armed bandits. Racing Algorithms (RAs) …


Design And Optimization Of Superjunction Vertical Dmos Power Transistors Using Sentaurus Device Simulation, Raul Mendoza Macias Jan 2016

Design And Optimization Of Superjunction Vertical Dmos Power Transistors Using Sentaurus Device Simulation, Raul Mendoza Macias

Electronic Theses and Dissertations

Vertical double-diffused metal oxide semiconductor (VDMOS) power transistor has been studied. The use of superjunction (SJ) in the drift region of VDMOS has been evaluated using three-dimensional device simulation. All relevant physical models in Sentaurus are turned on. The VDMOS device doping profile is obtained from process simulation. The superjunction VDMOS performance in off-state breakdown voltage and specific on-resistance is compared with that in conventional VDMOS structure. In addition, electrical parameters such as threshold voltage and charge balance are also examined. Increasing the superjunction doping in the drift region of VDMOS reduces the on-resistance by 26%, while maintaining the same …


Impact Of Wireless Channel Uncertainty Upon M-Ary Distributed Detection Systems., Zahra Hajibabaei Najafabadi Jan 2016

Impact Of Wireless Channel Uncertainty Upon M-Ary Distributed Detection Systems., Zahra Hajibabaei Najafabadi

Electronic Theses and Dissertations

We consider a wireless sensor network (WSN), consisting of several sensors and a fusion center (FC), which is tasked with solving an $M$-ary hypothesis testing problem. Sensors make $M$-ary decisions and transmit their digitally modulated decisions over orthogonal channels, which are subject to Rayleigh fading and noise, to the FC. Adopting Bayesian optimality criterion, we consider training and non-training based distributed detection systems and investigate the effect of imperfect channel state information (CSI) on the optimal maximum a posteriori probability (MAP) fusion rules and detection performance, when the sum of training and data symbol transmit powers is fixed. Our results …


Performance Evaluation Of Connectivity And Capacity Of Dynamic Spectrum Access Networks, Osama Al-Tameemi Jan 2016

Performance Evaluation Of Connectivity And Capacity Of Dynamic Spectrum Access Networks, Osama Al-Tameemi

Electronic Theses and Dissertations

Recent measurements on radio spectrum usage have revealed the abundance of under- utilized bands of spectrum that belong to licensed users. This necessitated the paradigm shift from static to dynamic spectrum access (DSA) where secondary networks utilize unused spectrum holes in the licensed bands without causing interference to the licensed user. However, wide scale deployment of these networks have been hindered due to lack of knowledge of expected performance in realistic environments and lack of cost-effective solutions for implementing spectrum database systems. In this dissertation, we address some of the fundamental challenges on how to improve the performance of DSA …


Design, Analysis, Implementation And Evaluation Of Real-Time Opportunistic Spectrum Access In Cloud-Based Cognitive Radio Networks, Nimish Sharma Jan 2016

Design, Analysis, Implementation And Evaluation Of Real-Time Opportunistic Spectrum Access In Cloud-Based Cognitive Radio Networks, Nimish Sharma

Electronic Theses and Dissertations

Opportunistic spectrum access in cognitive radio network is proposed for remediation of spectrum under-utilization caused by exclusive licensing for service providers that are intermittently utilizing spectrum at any given geolocation and time. The unlicensed secondary users (SUs) rely on opportunistic spectrum access to maximize spectrum utilization by sensing/identifying the idle bands without causing harmful interference to licensed primary users (PUs). In this thesis, Real-time Opportunistic Spectrum Access in Cloud-based Cognitive Radio Networks (ROAR) architecture is presented where cloud computing is used for processing and storage of idle channels. Software-defined radios (SDRs) are used as SUs and PUs that identify, report, …


Reduction Of Mutual Coupling In Antenna Technology Using Elliptically Shaped Metasurfaces, Gabriel Moreno Jan 2016

Reduction Of Mutual Coupling In Antenna Technology Using Elliptically Shaped Metasurfaces, Gabriel Moreno

Electronic Theses and Dissertations

This thesis is devoted to the use of metasurfaces for the goals of the reduction of mutual coupling between closely spaced antennas and the increase of antenna bandwidth. This is done first using a graphene monolayer as a cloak to decrease mutual coupling and restore radiation patterns for closely spaced antennas at THz frequencies. The introduction of the graphene monolayer was also extensively studied in regards to the effect on the radiation properties of the antennas. The use of metasurfaces also has other applications, in particular with the bandwidth of antennas, where an anisotropic metasurface can be used to drastically …


Performance Evaluation And Improvement Of Wireless Amplify-And-Forward Cooperative-Based Systems Under Nodes Mobility And Imperfect Csi Estimation Impacts, Yazid Khattabi Jan 2016

Performance Evaluation And Improvement Of Wireless Amplify-And-Forward Cooperative-Based Systems Under Nodes Mobility And Imperfect Csi Estimation Impacts, Yazid Khattabi

Electronic Theses and Dissertations

Cooperative communication techniques have been introduced in wireless networks to achieve spacial diversity-gain via the readiness of multiple users (via relays) to assist a source forwarding its data to a final destination. Cooperative communication techniques have shown their capability in improving system reliability and extending coverage area, and hence, it is believable that they will act as a promising technology for the coming fifth-generation (5G). Nevertheless, most existing work reported in literature on performance studies of wireless cooperative-based systems are based on the assumptions that the multipath fading channels among systems cooperating nodes are quasi-static (i.e., fading channels coefficients are …