Development Of An Improved Microwave Ocean Surface Emissivity Radiative Transfer Model,
2010
University of Central Florida
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 …
Highly Integrated Dc-Dc Converters,
2010
University of Central Florida
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,
2010
University of Central Florida
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 …
A New Development Of Feedback Controller For Left Ventricular Assist Device,
2010
University of Central Florida
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 …
The Relevance Of Time-To-Digital Converters To Small Platform Direction Finding Systems,
2010
University of Central Florida
The Relevance Of Time-To-Digital Converters To Small Platform Direction Finding Systems, Paul Jeffrey Nelson
Electronic Theses and Dissertations
This thesis explores a Time-Difference-of-Arrival (TDOA) approach to radio direction finding, utilizing picosecond-resolution Time-to-Digital Converters (TDCs). By measuring the relative time of arrival of a pulsed RF signal impinging on an antenna array, direction of arrival (DOA) can be ascertained. This technology enables versatile DOA calculation on platforms only several meters in length, and offers various size, weight, power, and cost advantages when compared to present DF technologies. A short baseline S-band TDOA DF system utilizing TDCs is designed, fabricated, and tested in a laboratory environment. This research suggests that such a DF system based on TDCs provides sufficient accuracy …
High-Density And High-Efficiency Soft Switching Modular Bi-Directional Dc-Dc Converter For Hybrid Electric Vehicles,
2010
University of Central Florida
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. …
Three-Port Micro-Inverter With Power Decoupling Capability For Photovoltaic (Pv) Systems Applications,
2010
University of Central Florida
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 …
Reconfigurable Architecture For H.264/Avc Variable Block Size Motion Estimation Based On Motion Activity And Adaptive Search Range,
2010
University of Central Florida
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 …
Validation Of Wideband Ocean Emissivity Radiative Transfer Model,
2010
University of Central Florida
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 …
Evaluating The Benefits Of 3d Stereo In Modern Video Games,
2010
University of Central Florida
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, …
Modeling And Simulation Of Soft Bodies,
2010
University of Central Florida
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 …
Extreme Ultraviolet Spectral Streak Camera,
2010
University of Central Florida
Extreme Ultraviolet Spectral Streak Camera, John Michael Szilagyi
Electronic Theses and Dissertations
The recent development of extreme ultraviolet (EUV) sources has increased the need for diagnostic tools, and has opened up a previously limited portion of the spectrum. With ultrafast laser systems and spectroscopy moving into shorter timescales and wavelengths, the need for nanosecond scale imaging of EUV is increasing. EUV’s high absorption has limited the number of imaging options due to the many atomic resonances in this spectrum. Currently EUV is imaged with photodiodes and X-ray CCDs. However photodiodes are limited in that they can only resolve intensity with respect to time and X-ray CCDs are limited to temporal resolution in …
Researches On Reverse Lookup Problem In Distributed File System,
2010
University of Central Florida
Researches On Reverse Lookup Problem In Distributed File System, Junyao Zhang
Electronic Theses and Dissertations
Recent years have witnessed an increasing demand for super data clusters. The super data clusters have reached the petabyte-scale can consist of thousands or tens of thousands storage nodes at a single site. For this architecture, reliability is becoming a great concern. In order to achieve a high reliability, data recovery and node reconstruction is a must. Although extensive research works have investigated how to sustain high performance and high reliability in case of node failures at large scale, a reverse lookup problem, namely finding the objects list for the failed node remains open. This is especially true for storage …
Analysis Of Periodic Structures Using Finite-Difference Time-Domain Method,
2010
University of Mississippi
Analysis Of Periodic Structures Using Finite-Difference Time-Domain Method, Khaled Elmahgoub
Electronic Theses and Dissertations
Periodic structures are of great importance in electromagnetics these days due to their wide range of applications such as frequency selective surfaces (FSS), electromagnetic band gap, periodic absorbers, metamaterials and many others. The aim of this work is to develop several algorithms to analyze different types of electromagnetic periodic structures using the constant horizontal wavenumber finite-difference time-domain periodic boundary condition (FDTD/PBC). A new FDTD/PBC approach is introduced to analyze the scattering properties of general skegrid periodic structures. The approach is simple to implement and efficient in terms of both computational time and memory usage. In addition, an efficient hybrid FDTD …
Super-High-Frequency Two-Port Aln Contour-Mode Resonators For Rf Applications,
2010
University of Pennsylvania
Super-High-Frequency Two-Port Aln Contour-Mode Resonators For Rf Applications, Matteo Rinaldi, Chiara Zuniga, Chengjie Zuo, Gianluca Piazza
Departmental Papers (ESE)
This paper reports on the design and experimental verification of a new class of thin-film (250 nm) superhigh- frequency laterally-vibrating piezoelectric microelectromechanical (MEMS) resonators suitable for the fabrication of narrow-band MEMS filters operating at frequencies above 3 GHz. The device dimensions have been opportunely scaled both in the lateral and vertical dimensions to excite a contourextensional mode of vibration in nanofeatures of an ultra-thin (250 nm) AlN film. In this first demonstration, 2-port resonators vibrating up to 4.5 GHz have been fabricated on the same die and attained electromechanical coupling, kt^2, in excess of 1.5%. These devices are employed to …
The Size Ellect On The Infrared Spectra Of Condensed Media Under Conditions Of Id, 2d And 3d Dielectric Confinement,
2010
Vavilov State Optical Institute, St. Petersburg
The Size Ellect On The Infrared Spectra Of Condensed Media Under Conditions Of Id, 2d And 3d Dielectric Confinement, Igor I. Shaganov, Tatiana S. Perova, Vasily A. Melnikov, Kevin Berwick
Articles
A general expression for the dielectric loss spectrum of an absorbing composite medium was obtained from a Maxwell-Garnett general equation. This expression was simplified for the cases of one, two and three dimensional dielectric confinement in both ordered and disordered thin layers, rods (wires) and spheres of absorbing medium which are considered as mesoparticles or mesoscopic molecules. This theoretical approach was verified experimentally using high purity organic liquids with strong absorption bands in the infrared range. Three organic liquids, namely benzene, chloroform and carbon disulphide, were measured in various dielectric confinement configurations using Fourier Transform Infrared (FTIR) spectroscopy with a …
Computer-Aided Detection Of Sleep Apnea And Sleep Stage Classification Using Hrv And Eeg Signals,
2010
University of Texas at El Paso
Computer-Aided Detection Of Sleep Apnea And Sleep Stage Classification Using Hrv And Eeg Signals, Edson F. Estrada
Open Access Theses & Dissertations
Sleep is a circadian rhythm essential for human life. Many events occur in the body during this state. In the past, significant efforts have been made to provide clinicians with reliable and less intrusive tools to automatically classify the sleep stages and detect apnea events. A few systems are available in the market to accomplish this task. However, sleep specialists may not have full confidence and trust in such systems due to issues related to their accuracy, sensitivity and specificity. The main objective of this work is to explore possible relationships among sleep stages and apneic events and improve on …
Sensor Interpolation And Super Resolution Image Reconstruction Using The Optimal Recovery Framework,
2010
University of Texas at El Paso
Sensor Interpolation And Super Resolution Image Reconstruction Using The Optimal Recovery Framework, Veenarai Moram
Open Access Theses & Dissertations
Wireless sensor networks have the potential to benefit society in a myriad of ways, but due to constraints of sensor placement, obtaining the desired signals is not an easy problem. Retrieving the information accurately from sensors placed randomly is a challenging problem of sensor communication and signal interpolation. In this research the optimal recovery (OR) method, a deterministic framework that can use a priori bandwidth or spectral shape information, is used to interpolate from the given samples produced by sensors. In the reconstruction formulation, a worst case error signal occurs. To minimize this error, the OR method uses a norm …
Resistive Switching Of Tin Dioxide (Sno2) For Memristor Applications,
2010
University of Texas at El Paso
Resistive Switching Of Tin Dioxide (Sno2) For Memristor Applications, Sergio Fabian Almeida
Open Access Theses & Dissertations
In the last decades new electrical devices have been investigated in order to overcome problems caused by integrated circuit shrinking. Within these devices there is one that has attracted much attention due to its high scalability and simple structure. This device was proposed theoretically by Leon Chua in 1971 who gave it the name of "Memristor". In the recent years thin films structures composed of a metal/oxide/metal (MOM) stack have been linked to this new device, also known as "Resistive switching". There are several applications for the memristor; one of the most important is for resistive random access memory (ReRAM) …
A Subthreshold Reconfigurable Architecture For Harsh Environments,
2010
University of Texas at El Paso
A Subthreshold Reconfigurable Architecture For Harsh Environments, Ameet O. Chavan
Open Access Theses & Dissertations
Energy harvesting and functional reconfigurability are necessary features in order to simultaneously achieve longer operating lifetimes and versatility in application for many next generation electronic systems. The presented research incorporates capabilities that not only enable applications to self-power from ambience but also permit change in functionality based on real-time application requirements. Currently, many applications are battery powered with custom hardware, which severely confines the application platform. Moreover, maintenance and upgrades are prohibitively expensive, particularly in the case of remote locations with limited accessibility. For harsh environments like Space or the battlefield, apart from features such as low power and econfigurability, …
