On Kernel-Base Multi-Task Learning,
2014
University of Central Florida
On Kernel-Base Multi-Task Learning, Cong Li
Electronic Theses and Dissertations
Multi-Task Learning (MTL) has been an active research area in machine learning for two decades. By training multiple relevant tasks simultaneously with information shared across tasks, it is possible to improve the generalization performance of each task, compared to training each individual task independently. During the past decade, most MTL research has been based on the Regularization-Loss framework due to its flexibility in specifying various types of information sharing strategies, the opportunity it offers to yield a kernel-based methods and its capability in promoting sparse feature representations. However, certain limitations exist in both theoretical and practical aspects of Regularization-Loss-based MTL. …
Conae Microwave Radiometer (Mwr) Counts To Brightness Temperature Algorithm,
2014
University of Central Florida
Conae Microwave Radiometer (Mwr) Counts To Brightness Temperature Algorithm, Zoubair Ghazi
Electronic Theses and Dissertations
This dissertation concerns the development of the MicroWave Radiometer (MWR) brightness temperature (Tb) algorithm and the associated algorithm validation using on-orbit MWR Tb measurements. This research is sponsored by the NASA Earth Sciences Aquarius Mission, a joint international science mission, between NASA and the Argentine Space Agency (Comision Nacional de Actividades Espaciales, CONAE). The MWR is a CONAE developed passive microwave instrument operating at 23.8 GHz (K-band) H-pol and 36.5 GHz (Ka-band) H- and V-pol designed to complement the Aquarius L-band radiometer/scatterometer, which is the prime sensor for measuring sea surface salinity (SSS). MWR measures the Earth's brightness temperature and …
Practical Implementations Of The Active Set Method For Support Vector Machine Training With Semi-Definite Kernels,
2014
University of Central Florida
Practical Implementations Of The Active Set Method For Support Vector Machine Training With Semi-Definite Kernels, Christopher Sentelle
Electronic Theses and Dissertations
The Support Vector Machine (SVM) is a popular binary classification model due to its superior generalization performance, relative ease-of-use, and applicability of kernel methods. SVM training entails solving an associated quadratic programming (QP) that presents significant challenges in terms of speed and memory constraints for very large datasets; therefore, research on numerical optimization techniques tailored to SVM training is vast. Slow training times are especially of concern when one considers that re-training is often necessary at several values of the models regularization parameter, C, as well as associated kernel parameters. The active set method is suitable for solving SVM problem …
Transparent Oxide Semiconductor Gate Based Mosfets For Sensor Applications,
2014
University of Central Florida
Transparent Oxide Semiconductor Gate Based Mosfets For Sensor Applications, Ashwin Kumar Saikumar
Electronic Theses and Dissertations
Starting from small scale laboratories to the highly sophisticated industrial facilities, monitoring and control forms the most integral part. In order to perform this continuous monitoring we require an interface, that would operate between the system and its processing conditions and in turn which facilitates us to act accordingly. This interface is called as a sensor. There are various types of sensors available which have wide range of functionality in various different fields. The use of transparent conducting oxide (TCO) in the field of sensor applications has increased and has been the subject of extensive research. Good electrical properties, good …
Modeling And Fault Detection In Dc Side Of Photovoltaic Arrays,
2014
University of Central Florida
Modeling And Fault Detection In Dc Side Of Photovoltaic Arrays, Mohd Akram
Electronic Theses and Dissertations
Fault detection in PV systems is a key factor in maintaining the integrity of any PV system. Faults in photovoltaic systems can cause irrevocable damages to the stability of the PV system and substantially decrease the power output generated from the array of PV modules. Among'st the various AC and DC faults in a PV system, the clearance of the AC side faults is achieved by conventional AC protection schemes,the DC side, however , there still exists certain faults which are difficult to detect and clear. This paper deals with the modeling, detection and classification of these types of DC …
Visual Geo-Localization And Location-Aware Image Understanding,
2014
University of Central Florida
Visual Geo-Localization And Location-Aware Image Understanding, Amir Roshan Zamir
Electronic Theses and Dissertations
Geo-localization is the problem of discovering the location where an image or video was captured. Recently, large scale geo-localization methods which are devised for ground-level imagery and employ techniques similar to image matching have attracted much interest. In these methods, given a reference dataset composed of geo-tagged images, the problem is to estimate the geo-location of a query by finding its matching reference images. In this dissertation, we address three questions central to geo-spatial analysis of ground-level imagery: 1) How to geo-localize images and videos captured at unknown locations? 2) How to refine the geo-location of already geo-tagged data? 3) …
Rf Energy Harvesting For Implantable Ics With On-Chip Antenna,
2014
University of Central Florida
Rf Energy Harvesting For Implantable Ics With On-Chip Antenna, Yu-Chun Liu
Electronic Theses and Dissertations
Nowadays, as aging population increasing yearly, the health care technologies for elder people who commonly have high blood pressure or Glaucoma issues have attracted much attention. In order to care of those people, implantable integrated circuits (ICs) in human body are the direct solution to have 24/7 days monitoring with real-time data for diagnosis by patients themselves or doctors. However, due to the small size requirement for the implanted ICs located in human organs, it's quite challenging to integrate with transmitting and receiving antenna in a single chip, especially operating in 5.8-GHz ISM band. This research proposes a new idea …
Identifying Influential Agents In Social Systems,
2014
University of Central Florida
Identifying Influential Agents In Social Systems, Mahsa Maghami
Electronic Theses and Dissertations
This dissertation addresses the problem of influence maximization in social networks. In- fluence maximization is applicable to many types of real-world problems, including modeling contagion, technology adoption, and viral marketing. Here we examine an advertisement domain in which the overarching goal is to find the influential nodes in a social network, based on the network structure and the interactions, as targets of advertisement. The assumption is that advertisement budget limits prevent us from sending the advertisement to everybody in the network. Therefore, a wise selection of the people can be beneficial in increasing the product adoption. To model these social …
Investigation Of Dual-Stage High Efficiency And Density Micro Inverter For Solar Application,
2014
University of Central Florida
Investigation Of Dual-Stage High Efficiency And Density Micro Inverter For Solar Application, Lin Chen
Electronic Theses and Dissertations
Module integrated converters (MIC), also called micro inverter, in single phase have witnessed recent market success due to unique features (1) improved energy harvest, (2) improved system efficiency, (3) lower installation costs, (4) plug-N-play operation, (5) and enhanced flexibility and modularity. The MIC sector has grown from a niche market to mainstream, especially in the United States. Due to the fact that two-stage architecture is commonly used for single phase MIC application. A DC-DC stage with maximum power point tracking to boost the output voltage of the Photovoltaic (PV) panel is employed in the first stage, DC-AC stage is used …
Voltage Smoothing With A Capacitor,
2014
University of South Florida
Voltage Smoothing With A Capacitor, Martin Copello
Undergraduate Journal of Mathematical Modeling: One + Two
A rectifier is an electrical circuit that converts alternating current to direct current, e.g., a half wave rectifier removes lower valleys of the AC voltage wave. If a capacitor is placed in parallel with a half wave rectifier, the transition from voltage peak to peak is smoothed to closer resemble constant DC voltage. The objective of this project was to model the voltage changes of a half wave rectifier with a parallel capacitor. It was found that the smoothness of the voltage waves increased as the capacitance of the capacitor increased.
Active Current Injection Method For Limiting Ground Fault Current Harmonics In Underground Coal Mines,
2014
University of Kentucky
Active Current Injection Method For Limiting Ground Fault Current Harmonics In Underground Coal Mines, Yigong Zhang
Theses and Dissertations--Mining Engineering
Current practice in U.S. underground coal mine high-voltage distribution systems is to attempt to limit ground fault current to 25 Amperes and de-energize the circuit at 10 Amperes. However, the significant amount of system capacitance due to the use of shielded cables can cause ground fault current to be two or three times the intended ground fault limit. Consequently, this practice can cause several issues such as ground fault currents significantly exceeding the neutral grounding resistor current limit, loss of relay selectivity in the distribution system, and transient overvoltages in certain ground fault situations. These issues are solved to some …
Service And Communication Management In Cooperative Vehicular Networks,
2014
Nimbus Centre for Embedded Systems Research, Department of Electronic Engineering, Cork Institute of Technology, Cork, Ireland.
Service And Communication Management In Cooperative Vehicular Networks, Olivia Brickley
Theses
The concept of Intelligent Transportation Systems (ITS) presents new R&D challenges for the transportation and ICT sectors and is currently receiving considerable interest from the research community. The primary objective of ITS is the creation of advanced road traffic systems for improved traffic safety, efficiency, and travelling comfort. Basic vehicle and roadside infrastructure collaboration allows for an increase in efficiency and safety and acts as the foundation for an extensive service set to achieve these ITS goals. Applications such as journey planning, automatic tolling and emergency warnings, among others, are envisaged in a system which can potentially reform modern transportation. …
Location Management And Hybrid Geo-Routing For Urban Vehicular Networks,
2014
Department of Electronic Engineering, Cork Institute of Technology, Cork, Ireland
Location Management And Hybrid Geo-Routing For Urban Vehicular Networks, Aisling O'Driscoll
Theses
In recent years the motivation for comfort applications e.g. infotainment, file exchange and vehicle to vehicle (V2V) multiplayer gaming amongst others, has emerged as an active area of vehicular communications and network research. The success of such applications relies on the ability of a geo-routing protocol to deliver communication packets in a frequently disconnected communication environment. To do this, the location of the destination vehicle must first be determined and secondly, must reliably deliver the packet from source to destination. To determine the location of a target vehicle towards which packets can be forwarded, geo-routing algorithms utilise a location service …
Rss Based Localization In A Rayleigh Fading Environment,
2014
University of Mississippi
Rss Based Localization In A Rayleigh Fading Environment, Rojina Adhikary
Electronic Theses and Dissertations
The objective of this thesis is to quantify the improvement that can be obtained in sensor agent localization accuracy as a function of the number of multipath components that can be resolved. We assume that a known number sensor agents are located at unknown coordinates within a rectangular grid having anchors at the corner locations, whose locations are known. Further, we assume fading is Rayleigh and that the propagation constant is constant but unknown. Also, we assume that modulation is spread spectrum and that either the sensors or agents are capable of resolving multipath components down to the chip level …
Adaptive Relay-Selection In Decode-And-Forward Cooperative Systems,
2014
University of Mississippi
Adaptive Relay-Selection In Decode-And-Forward Cooperative Systems, Adham Ahmed Hagag
Electronic Theses and Dissertations
In the past few years adaptive decode-and-forward cooperative diversity systems have been studied intensively in literature. Many schemes and protocols have been proposed to enhance the performance of the cooperative systems while trying to alleviate its drawbacks. One of the recent schemes that had been shown to give high improvements in performance is the best-relay selection scheme. In the best-relay selection scheme only one relaying nodes among the relays available in the system is selected to forward the source's message to the destination. The best relay is selected as the relay node that can achieve the highest end-to-end signal-to-noise ratio …
Design And Implementation Of An X-Band Passive Rfid Tag,
2014
North Carolina Agricultural and Technical State University
Design And Implementation Of An X-Band Passive Rfid Tag, Praharshin Melaka Senadeera
Dissertations
This research presents a novel fully integrated energy harvester, matching network, multi-stage RF-DC rectifier, mode selector, RC oscillator, LC oscillator, and X-band power amplifier implemented in IBM 0.18-µm RF CMOS technology. We investigated different matching schemes, antennas, and rectifiers with focus on the interaction between building blocks. Currently the power amplifier gives the maximum output power of 5.23 dBm at 9.1GHz. The entire RFID tag circuit was designed to operate in low power consumption. Voltage sensor circuit which generates the enable signal was designed to operate in very low current. All the test blocks of the RFID tag were tested. …
Investigation Of Hfox/Cu Resistive Memory For Advanced Encryption Applications,
2014
University at Albany, State University of New York
Investigation Of Hfox/Cu Resistive Memory For Advanced Encryption Applications, Benjamin David Briggs
Legacy Theses & Dissertations (2009 - 2024)
The Advanced Encryption Standard (AES) is a widely used encryption algorithm to protect data and communications in today's digital age. Modern AES CMOS implementations require large amounts of dedicated logic and must be tuned for either performance or power consumption. A high throughput, low power, and low die area AES implementation is required in the growing mobile sector. An emerging non-volatile memory device known as resistive memory (ReRAM) is a simple metal-insulator-metal capacitor device structure with the ability to switch between two stable resistance states. Currently, ReRAM is targeted as a non-volatile memory replacement technology to eventually replace flash. Its …
Development Of Novel Technologies To Enhance Performance And Reliability Of Iii-Nitride Avalanche Photodiodes,
2014
University at Albany, State University of New York
Development Of Novel Technologies To Enhance Performance And Reliability Of Iii-Nitride Avalanche Photodiodes, Puneet Harischandra Suvarna
Legacy Theses & Dissertations (2009 - 2024)
Solar-blind ultraviolet avalanche photodiodes are an enabling technology for applications in the fields of astronomy, communication, missile warning systems, biological agent detection and particle physics research. Avalanche photodiodes (APDs) are capable of detecting low-intensity light with high quantum efficiency and signal-to-noise ratio without the need for external amplification. The properties of III-N materials (GaN and AlGaN) are promising for UV photodetectors that are highly efficient, radiation-hard and capable of visible-blind or solar-blind operation without the need for external filters. However, the realization of reliable and high performance III-N APDs and imaging arrays has several technological challenges. The high price and …
Oxide Defect Engineering Methods For Valence Change (Vcm) Resistive Random Access Memories,
2014
University at Albany, State University of New York
Oxide Defect Engineering Methods For Valence Change (Vcm) Resistive Random Access Memories, Jihan Ocampo Capulong
Legacy Theses & Dissertations (2009 - 2024)
Electrical switching requirements for resistive random access memory (ReRAM) devices are multifaceted, based on device application. Thus, it is important to obtain an understanding of these switching properties and how they relate to the oxygen vacancy concentration and oxygen vacancy defects. Oxygen vacancy defects in the switching oxide of valence-change-based ReRAM (VCM ReRAM) play a significant role in device switching properties. Oxygen vacancies facilitate resistive switching as they form the conductive filament that changes the resistance state of the device. This dissertation will present two methods of modulating the defect concentration in VCM ReRAM composed of Pt/HfOx/Ti stack: …
Development Of A One-Dimensional Position Sensitive Detector For Tracking Applications,
2014
University at Albany, State University of New York
Development Of A One-Dimensional Position Sensitive Detector For Tracking Applications, Leigh Kent Lydecker
Legacy Theses & Dissertations (2009 - 2024)
Optical Position Sensitive Detectors (PSDs) are a non-contact method of tracking the location of a light spot. Silicon-based versions of such sensors are fabricated with standard CMOS processing, are inexpensive and provide a real-time, analog signal output corresponding to the position of the light spot. Because they are non-contact, they do not degrade over time from surface friction due to repetitive sliding motion associated with standard full contact sliding potentiometers. This results in long, reliable device lifetimes. In this work, an innovative PSD was developed to replace the linear hard contact potentiometer currently being used in a human-computer interface architecture.
