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Concentric Layout, A New Scientific Data Layout For Matrix Data Set In Hadoop File System, Lu Cheng
Concentric Layout, A New Scientific Data Layout For Matrix Data Set In Hadoop File System, Lu Cheng
Electronic Theses and Dissertations
The data generated by scientific simulation, sensor, monitor or optical telescope has increased with dramatic speed. In order to analyze the raw data speed and space efficiently, data preprocess operation is needed to achieve better performance in data analysis phase. Current research shows an increasing tread of adopting MapReduce framework for large scale data processing. However, the data access patterns which generally applied to scientific data set are not supported by current MapReduce framework directly. The gap between the requirement from analytics application and the property of MapReduce framework motivates us to provide support for these data access patterns in …
Modeling And Simulation Of Soft Bodies, Jaruwan Mesit
Modeling And Simulation Of Soft Bodies, Jaruwan Mesit
Electronic Theses and Dissertations
As graphics and simulations become more realistic, techniques for approximating soft body objects, that is, non-solid objects such as liquids, gases, and cloth, are becoming increasingly common. The proposed generalized soft body method encompasses some specific cases of other existing models enabling simulation of a variety of soft body materials by parameter adjustment. This research presents a general method of soft body model and simulation in which parameters for body control, surface deformation, volume control, and gravitation, can be adjusted to simulate different types of soft bodies. In this method, the soft body mesh structure maintains configuration among surface points …
Establishing Degradation Rates And Service Lifetime Of Photovoltaic Systems, Albert Leyte-Vidal
Establishing Degradation Rates And Service Lifetime Of Photovoltaic Systems, Albert Leyte-Vidal
Electronic Theses and Dissertations
As fossil fuel sources continue to diminish, oil prices continue to increase, and global warming and CO2 emissions keep impacting the environment, it has been necessary to shift energy consumption and generation to a different path. Solar energy has proven to be one of the most promising sources of renewable energy because it is environmentally friendly, available anywhere in the world, and cost competitive. For photovoltaic (PV) system engineers, designing a PV system is not an easy task. Research demonstrates that different PV technologies behave differently under certain conditions; therefore energy production varies not only with capacity of the system …
Highly Integrated Dc-Dc Converters, Hongwei Jia
Highly Integrated Dc-Dc Converters, Hongwei Jia
Electronic Theses and Dissertations
A monolithically integrated smart rectifier has been presented first in this work. The smart rectifier, which integrates a power MOSFET, gate driver and control circuitry, operates in a self-synchronized fashion based on its drain-source voltage, and does not need external control input. The analysis, simulation, and design considerations are described in detail. A 5V, 5-µm CMOS process was used to fabricate the prototype. Experimental results show that the proposed rectifier functions as expected in the design. Since no dead-time control needs to be used to switch the sync-FET and ctrl-FET, it is expected that the body diode losses can be …
Design And Simulation For Encoded Pn-Ofc Saw Sensor Systems, John Pavlina
Design And Simulation For Encoded Pn-Ofc Saw Sensor Systems, John Pavlina
Electronic Theses and Dissertations
Surface acoustic wave (SAW) sensors provide versatility in that they can offer wireless, passive operation in numerous environments. Various SAW device embodiments may also be employed for retrieval of the sensed data. Single sensor systems typically use a single carrier frequency and a simple device embodiment since tagging is not required. However, it is necessary in a multi-sensor environment to both identify the sensor and retrieve the information. Overlapping sensor data signals in time and frequency present problems when attempting to collect the sensed data at the receiver. This dissertation defines a system simulation environment exclusive to SAW sensors. The …
The Pdf Of Irradiance For A Free-Space Optical Communications Channel: A Physics Based Model, David Wayne
The Pdf Of Irradiance For A Free-Space Optical Communications Channel: A Physics Based Model, David Wayne
Electronic Theses and Dissertations
An accurate PDF of irradiance for a FSO channel is important when designing a laser radar, active laser imaging, or a communications system to operate over the channel. Parameters such as detector threshold level, probability of detection, mean fade time, number of fades, BER, and SNR are derived from the PDF and determine the design constraints of the receiver, transmitter, and corresponding electronics. Current PDF models of irradiance, such as the Gamma-Gamma, do not fully capture the effect of aperture averaging; a reduction in scintillation as the diameter of the collecting optic is increased. The Gamma-Gamma PDF of irradiance is …
Evaluating The Benefits Of 3d Stereo In Modern Video Games, Tad Litwiller
Evaluating The Benefits Of 3d Stereo In Modern Video Games, Tad Litwiller
Electronic Theses and Dissertations
We present a study that investigates user performance benefits of 3D stereo in modern video games. Based on an analysis of several video games that are best suited for use with commercial 3D stereo drivers and vision systems, we chose five modern titles focusing on racing, first person shooter, third person shooter, and sports game genres. For each game, quantitative and qualitative measures were taken to determine if users performed better and learned faster in the experimental group (3D stereo display) than in the control group (2D display). A game experience pre-questionnaire was used to classify participants into beginner, intermediate, …
Query Processing In Location-Based Services, Fuyu Liu
Query Processing In Location-Based Services, Fuyu Liu
Electronic Theses and Dissertations
With the advances in wireless communication technology and advanced positioning systems, a variety of Location-Based Services (LBS) become available to the public. Mobile users can issue location-based queries to probe their surrounding environments. One important type of query in LBS is moving monitoring queries over mobile objects. Due to the high frequency in location updates and the expensive cost of continuous query processing, server computation capacity and wireless communication bandwidth are the two limiting factors for large-scale deployment of moving object database systems. To address both of the scalability factors, distributed computing has been considered. These schemes enable moving objects …
Three-Port Micro-Inverter With Power Decoupling Capability For Photovoltaic (Pv) Systems Applications, Souhib Harb
Three-Port Micro-Inverter With Power Decoupling Capability For Photovoltaic (Pv) Systems Applications, Souhib Harb
Electronic Theses and Dissertations
The Photovoltaic (PV) systems have been realized using different architectures, starting with the string and centralized PV system to the modular PV system. Presently, decentralized inverters are being developed at the PV panel power level (known as AC – PV Modules). Such new PV systems are becoming more attractive and many expect this will be the trend of the future. The AC-Module PV system consists of an inverter attached to one PV panel. This integration requires that both devices have the same life-span. Although, the available commercial inverters have a relatively short life-span (10 years) compared to the 25 –year …
Design Of Silicon Controlled Rectifers Sic] For Robust Electrostatic Discharge Protection Applications, Zhiwei Liu
Design Of Silicon Controlled Rectifers Sic] For Robust Electrostatic Discharge Protection Applications, Zhiwei Liu
Electronic Theses and Dissertations
Electrostatic Discharge (ESD) phenomenon happens everywhere in our daily life. And it can occurs through the whole lifespan of an Integrated Circuit (IC), from the early wafer fabrication process, extending to assembly operation, and finally ending at the user‟s site. It has been reported that up to 35% of total IC field failures are ESD-induced, with estimated annual costs to the IC industry running to several billion dollars. The most straightforward way to avoid the ICs suffering from the threatening of ESD damages is to develop on-chip ESD protection circuits which can afford a robust, low-impedance bypassing path to divert …
Control Strategy For Maximizing Power Conversion Efficiency And Effectiveness Of Three Port Solar Charging Station For Electric Vehicles, Christopher Hamilton
Control Strategy For Maximizing Power Conversion Efficiency And Effectiveness Of Three Port Solar Charging Station For Electric Vehicles, Christopher Hamilton
Electronic Theses and Dissertations
Recent trends in the energy sector have provided opportunities in the research of alternative energy sources and optimization of systems that harness these energy sources. With the rising cost of fossil fuel and rising concern about detrimental effects that fossil fuel consumption has on the environment, electric vehicles are becoming more prevalent. A study put out in 2009 gives a prediction that in the year 2025, 20% of new vehicles will be PHEVs.[1] As energy providers become more concerned about a growing population and diminishing energy source, they are looking into alternative energy sources such as wind and solar power. …
Conventional And Zvt Synchronous Buck Converter Design, Analysis, And Measurement, Mark Cory
Conventional And Zvt Synchronous Buck Converter Design, Analysis, And Measurement, Mark Cory
Electronic Theses and Dissertations
The role played by power converting circuits is extremely important to almost any electronic system built today. Circuits that use converters of any type depend on power that is consistent in form and reliable in order to properly function. In addition, today's demands require more efficient use of energy, from large stationary systems such as power plants all the way down to small mobile devices such as laptops and cell phones. This places a need to reduce any losses to a minimum. The power conversion circuitry in a system is a very good place to reduce a large amount of …
Hurricane Wind Speed And Rain Rate Measurements Using The Airborne Hurricane Imaging Radiometer (Hirad), Ruba Amarin
Hurricane Wind Speed And Rain Rate Measurements Using The Airborne Hurricane Imaging Radiometer (Hirad), Ruba Amarin
Electronic Theses and Dissertations
This dissertation presents results for an end-to-end computer simulation of a new airborne microwave remote sensor, the Hurricane Imaging Radiometer, HIRAD, which will provide improved hurricane surveillance. The emphasis of this research is the retrieval of hurricane-force wind speeds in the presence of intense rain and over long atmospheric slant path lengths that are encountered across its wide swath. Brightness temperature (Tb) simulations are performed using a forward microwave radiative transfer model (RTM) that includes an ocean surface emissivity model at high wind speeds developed especially for HIRAD high incidence angle measurements and a rain model for the hurricane environment. …
Live Video Database Management Systems, Rui Peng
Live Video Database Management Systems, Rui Peng
Electronic Theses and Dissertations
With the proliferation of inexpensive cameras and the availability of high-speed wired and wireless networks, networks of distributed cameras are becoming an enabling technology for a broad range of interdisciplinary applications in domains such as public safety and security, manufacturing, transportation, and healthcare. Today’s live video processing systems on networks of distributed cameras, however, are designed for specific classes of applications. To provide a generic query processing platform for applications of distributed camera networks, we designed and implemented a new class of general purpose database management systems, the live video database management system (LVDBMS). We view networked video cameras as …
Study Of The Interactions Of Proteins, Cells And Tissue With Biomaterials, Abhijeet Bhalkikar
Study Of The Interactions Of Proteins, Cells And Tissue With Biomaterials, Abhijeet Bhalkikar
Electronic Theses and Dissertations
Bioengineering is the application of engineering principles to address challenges in the fields of biology and medicine. Biomaterials play a major role in bioengineering. This work employs a three level approach to study the various interactions of biomaterials with proteins, cells and tissue in vitro. In the first study, we qualitatively and quantitatively analyzed the process of protein adsorption of two enzymes to two different surface chemistries, which are commonly used in the field. In the second study, we attempted to engineer a tissue construct to build a biocompatible interface between a titanium substrate and human skin. In the third …
Architectural Support For Improving System Hardware/Software Reliability, Martin Dimitrov
Architectural Support For Improving System Hardware/Software Reliability, Martin Dimitrov
Electronic Theses and Dissertations
It is a great challenge to build reliable computer systems with unreliable hardware and buggy software. On one hand, software bugs account for as much as 40% of system failures and incur high cost, an estimate of $59.5B a year, on the US economy. On the other hand, under the current trends of technology scaling, transient faults (also known as soft errors) in the underlying hardware are predicted to grow at least in proportion to the number of devices being integrated, which further exacerbates the problem of system reliability. We propose several methods to improve system reliability both in terms …
Modeling And Design Of Multi-Port Dc/Dc Converters, Zhijun Qian
Modeling And Design Of Multi-Port Dc/Dc Converters, Zhijun Qian
Electronic Theses and Dissertations
In this dissertation, a new satellite platform power architecture based on paralleled three-port DC/DC converters is proposed to reduce the total satellite power system mass. Moreover, a fourport DC/DC converter is proposed for renewable energy applications where several renewable sources are employed. Compared to the traditional two-port converter, three-port or four-port converters are classified as multi-port converters. Multi-port converters have less component count and less conversion stage than the traditional power processing solution which adopts several independent two-port converters. Due to their advantages multi-port converters recently have attracted much attention in academia, resulting in many topologies for various applications. But …
High-Density And High-Efficiency Soft Switching Modular Bi-Directional Dc-Dc Converter For Hybrid Electric Vehicles, John Elmes
Electronic Theses and Dissertations
This dissertation1 presents the design of a high-density and high-efficiency soft-switching bi-directional DC-DC converter for hybrid-electric vehicles. The converter operates in a new bidirectional interleaved variable-frequency quasi-square-wave (QSW) mode, which enables high efficiency, high switching frequency, and high power-density. The converter presented utilizes a new variable frequency interleaving approach which allows for each module to operate in an interleaved position while allowing for tolerance in inductance and snubber capacitor values. The variable frequency interleaved soft-switching operation paired with a high-density nanocrystalline inductor and high-density system structure results in a very high performance converter, well exceeding that of the current technology. …
Robust Dialog Management Through A Context-Centric Architecture, Victor C. Hung
Robust Dialog Management Through A Context-Centric Architecture, Victor C. Hung
Electronic Theses and Dissertations
This dissertation presents and evaluates a method of managing spoken dialog interactions with a robust attention to fulfilling the human user’s goals in the presence of speech recognition limitations. Assistive speech-based embodied conversation agents are computer-based entities that interact with humans to help accomplish a certain task or communicate information via spoken input and output. A challenging aspect of this task involves open dialog, where the user is free to converse in an unstructured manner. With this style of input, the machine’s ability to communicate may be hindered by poor reception of utterances, caused by a user’s inadequate command of …
The Simulation And Control Of A Grid-Connected Wind Energy Conversion System, Shauna Mccartney
The Simulation And Control Of A Grid-Connected Wind Energy Conversion System, Shauna Mccartney
Electronic Theses and Dissertations
With the rising cost of petroleum, concerns about exhausting the fossil fuels we depend on for energy, and the subsequent impacts that the burning of these types of fuels have on the environment, countries around the world are paying close attention to the development of renewable types of energy. Consequently, researchers have been trying to develop ways to take advantage of different types of clean and renewable energy sources. Wind energy production, in particular, has been growing at an increasingly rapid rate, and will continue to do so in the future. In fact, it has become an integral part in …
Mitigating Misbehavior In Wireless Networks: A Game Theoretic Approach, Wenjing Wang
Mitigating Misbehavior In Wireless Networks: A Game Theoretic Approach, Wenjing Wang
Electronic Theses and Dissertations
In a distributed wireless system, multiple network nodes behave cooperatively towards a common goal. Though such assumptions on cooperation are desirable (e.g., controlling the transmit power level, reducing interference for each other, revealing private information, adhering to network policies) for analyzing and modeling, certain nodes belonging to a real-world system have often shown to deviate. These nodes, known as misbehaving nodes, bring more challenges to the design of the wireless network because the unreliable channel makes the actions of the nodes hidden from each other. In this dissertation, we analyze two types of misbehavior, namely, selfish noncooperation and malicious attacking. …
Characterization And Modeling Of A High Power Thin Disk Laster, Omar Rodriguez-Valls
Characterization And Modeling Of A High Power Thin Disk Laster, Omar Rodriguez-Valls
Electronic Theses and Dissertations
High power lasers have been adapted to material processing, energy, military and medical applications. In the Laser Plasma Laboratory at CREOL, UCF, high power lasers are used to produce highly ionized plasmas to generate EUV emission. This thesis examines the quality of a recently acquired high power thin disk laser through thermal modeling and beam parameter measurements. High power lasers suffer from thermally induced issues which degrade their operation. Thin disk lasers use an innovative heat extraction mechanism that eliminates the transverse thermal gradient within the gain medium associated with thermal lensing. A thorough review of current thin disk laser …
A New Development Of Feedback Controller For Left Ventricular Assist Device, Yu Wang
A New Development Of Feedback Controller For Left Ventricular Assist Device, Yu Wang
Electronic Theses and Dissertations
The rotary Left Ventricular Assist Device (LVAD) is a mechanical pump surgically implanted in patients with end-stage congestive heart failure to help maintain the flow of blood from the sick heart. The rotary type pumps are controlled by varying the impeller speed to control the amount of blood flowing through the LVAD. One important challenge in using these devices is to prevent the occurrence of excessive pumping of blood from the left ventricle (known as suction) that may cause it to collapse due to the high pump speed. The development of a proper feedback controller for the pump speed is …
Development Of An Improved Microwave Ocean Surface Emissivity Radiative Transfer Model, Salem El-Nimri
Development Of An Improved Microwave Ocean Surface Emissivity Radiative Transfer Model, Salem El-Nimri
Electronic Theses and Dissertations
An electromagnetic model is developed for predicting the microwave blackbody emission from the ocean surface over a wide range of frequencies, incidence angles, and wind vector (speed and direction) for both horizontal and vertical polarizations. This ocean surface emissivity model is intended to be incorporated into an oceanic radiative transfer model to be used for microwave radiometric applications including geophysical retrievals over oceans. The model development is based on a collection of published ocean emissivity measurements obtained from satellites, aircraft, field experiments, and laboratory measurements. This dissertation presents the details of methods used in the ocean surface emissivity model development …
Reconfigurable Architecture For H.264/Avc Variable Block Size Motion Estimation Based On Motion Activity And Adaptive Search Range, Sumedha Kodipyaka
Reconfigurable Architecture For H.264/Avc Variable Block Size Motion Estimation Based On Motion Activity And Adaptive Search Range, Sumedha Kodipyaka
Electronic Theses and Dissertations
Motion Estimation (ME) technique plays a key role in the video coding systems to achieve high compression ratios by removing temporal redundancies among video frames. Especially in the newest H.264/AVC video coding standard, ME engine demands large amount of computational capabilities due to its support for wide range of different block sizes for a given macroblock in order to increase accuracy in finding best matching block in the previous frames. We propose scalable architecture for H.264/AVC Variable Block Size (VBS) Motion Estimation with adaptive computing capability to support various search ranges, input video resolutions, and frame rates. Hardware architecture of …
Bit-Rate Aware Reconfigurable Architecture For H.264/Avc Deblocking Filter, Rakan Khraisha
Bit-Rate Aware Reconfigurable Architecture For H.264/Avc Deblocking Filter, Rakan Khraisha
Electronic Theses and Dissertations
In H.264/AVC, DeBlocking Filter (DBF) achieves bit rate savings and it is used to improve visual quality by reducing the presence of blocking artifacts. However, these advantages come at the expense of increasing computational complexity of the DBF due to highly adaptive mode decision and small 4x4 block size. The DBF easily accounts for one third of the computational complexity of the decoder. The computational complexity required for various target applications from mobile to high definition video applications varies significantly. Therefore, it becomes apparent to design efficient architecture to adapt to different requirements. In this work, we exploit the scalability …
Validation Of Wideband Ocean Emissivity Radiative Transfer Model, Sonya Crofton
Validation Of Wideband Ocean Emissivity Radiative Transfer Model, Sonya Crofton
Electronic Theses and Dissertations
Radiative Transfer Models (RTM) have many applications in the satellite microwave remote sensing field, such as the retrieval of oceanic and atmospheric environmental parameters, including surface wind vectors and sea surface temperatures, integrated water vapor, cloud liquid, and precipitation. A key component of the ocean RTM is the emissivity model used to determine the brightness temperature (Tb) at the ocean’s surface. A new wideband ocean emissivity RTM developed by the Central Florida Remote Sensing Laboratory (CFRSL) calculates ocean emissivity over a wide range of frequencies, incidence angles, sea surface temperatures (SST), and wind speed. This thesis presents the validation of …
Class-E Cascode Power Amplifier Analysis And Design For Long Term Reliability, Karan Kutty
Class-E Cascode Power Amplifier Analysis And Design For Long Term Reliability, Karan Kutty
Electronic Theses and Dissertations
This study investigated the Class-E power amplifier operating at 5.2 GHz. Since the operation of this amplifier applies a lot of stress on the switching transistor, a cascode topology was applied in order to reduce the drain-source voltage stress. Such an amplifier was designed and optimized in order to improve stability, power added efficiency, and matching. A layout for the said design was then created to be fabrication-ready using the TSMC 0.18 um technology. Post-layout simulations were performed in order to realize a more realistic circuit performance with the layout design in mind. Long-term stress effects, such as oxide breakdown, …
Learning From Geometry In Learning For Tactical And Strategic Decision Domains, Jason Gauci
Learning From Geometry In Learning For Tactical And Strategic Decision Domains, Jason Gauci
Electronic Theses and Dissertations
Artificial neural networks (ANNs) are an abstraction of the low-level architecture of biological brains that are often applied in general problem solving and function approximation. Neuroevolution (NE), i.e. the evolution of ANNs, has proven effective at solving problems in a variety of domains. Information from the domain is input to the ANN, which outputs its desired actions. This dissertation presents a new NE algorithm called Hypercube-based NeuroEvolution of Augmenting Topologies (HyperNEAT), based on a novel indirect encoding of ANNs. The key insight in HyperNEAT is to make the algorithm aware of the geometry in which the ANNs are embedded and …
Phoneme-Based Video Indexing Using Phonetic Disparity Search, Carlos Leon Barth
Phoneme-Based Video Indexing Using Phonetic Disparity Search, Carlos Leon Barth
Electronic Theses and Dissertations
This dissertation presents and evaluates a method to the video indexing problem by investigating a categorization method that transcribes audio content through Automatic Speech Recognition (ASR) combined with Dynamic Contextualization (DC), Phonetic Disparity Search (PDS) and Metaphone indexation. The suggested approach applies genome pattern matching algorithms with computational summarization to build a database infrastructure that provides an indexed summary of the original audio content. PDS complements the contextual phoneme indexing approach by optimizing topic seek performance and accuracy in large video content structures. A prototype was established to translate news broadcast video into text and phonemes automatically by using ASR …