Engineering Commons^™

Analysis And Design Of Interleaving Multiphase Dc-To-Dc Converter With Input Lc Filter, Kevin Thomas Delrosso

Master's Theses

The future of microprocessors is unknown. Over the past 40 years, their historical trend has been for adopting smaller and more powerful designs that drive the world that we live in today. The state of the microprocessor business today faces a crossroad, wishing to continue on the historical trend of doubling the number of transistors on a chip every 18 months (Moore’s Law) but also facing the realistic task of needing to power these sophisticated devices. With the low voltages and high currents that are required for these microprocessors to operate, it poses a difficult task for the future designers …

High Speed Wavelength Tuning Of Sgdbr Lasers For Optical Coherence Tomography Applications, Benjamin Maher

Master's Theses

The application of Sample Grated Distributed Bragg Reflector (SGDBR) wavelength tunable lasers for swept-wavelength Optical Coherence Tomography (OCT) is explored. OCT is a method of measuring reflectivity versus distance into samples under test with a focused infrared light source. Swept wavelength OCT requires a laser light source that is capable of sweeping its wavelength quickly over the entire wavelength range of the tunable laser. Fast sweeping of the laser's wavelength enables real-time imaging of a wide surface area of the surface under test. This thesis will show that SGDBR lasers can be designed to meet the fast wavelength ramp speeds …

Hardware Architectures And Implementations For Associative Memories : The Building Blocks Of Hierarchically Distributed Memories, Changjian Gao

Dissertations and Theses

During the past several decades, the semiconductor industry has grown into a global industry with revenues around $300 billion. Intel no longer relies on only transistor scaling for higher CPU performance, but instead, focuses more on multiple cores on a single die. It has been projected that in 2016 most CMOS circuits will be manufactured with 22 nm process. The CMOS circuits will have a large number of defects. Especially when the transistor goes below sub-micron, the original deterministic circuits will start having probabilistic characteristics. Hence, it would be challenging to map traditional computational models onto probabilistic circuits, suggesting a …

Mosfet Modulated Dual Conversion Gain Cmos Image Sensors, Xiangli Li

Boise State University Theses and Dissertations

In recent years, vision systems based on CMOS image sensors have acquired significant ground over those based on charge-coupled devices (CCD). The main advantages of CMOS image sensors are their high level of integration, random accessibility, and low-voltage, low-power operation. Previously proposed high dynamic range enhancement schemes focused mainly on extending the sensor dynamic range at the high illumination end. Sensor dynamic range extension at the low illumination end has not been addressed. Since most applications require low-noise, high-sensitivity, characteristics for imaging of the dark region as well as dynamic range expansion to the bright region, the availability of a …

Surface Relief D-Fiber Bragg Gratings For Sensing Applications, Tyson Lee Lowder

Theses and Dissertations

This dissertation presents the novel creation of a surface relief fiber Bragg grating on the flat surface of a D-shaped optical fiber. In order to produce an efficient surface relief grating the grating must be etched into the surface of the glass fiber close to the core. A short etch that removes the cladding above the core is performed in order to decrease the core-to-flat distance and allow the light to interact with the grating on the flat surface. Due to the unique D-shape of the optical fiber the mechanical integrity of the fiber remains high even after the fabrication …

Cmol/Cmos Hardware Architectures And Performance/Price For Bayesian Memory - The Building Block Of Intelligent Systems, Mazad Shaheriar Zaveri

Dissertations and Theses

The semiconductor/computer industry has been following Moore's law for several decades and has reaped the benefits in speed and density of the resultant scaling. Transistor density has reached almost one billion per chip, and transistor delays are in picoseconds. However, scaling has slowed down, and the semiconductor industry is now facing several challenges. Hybrid CMOS/nano technologies, such as CMOL, are considered as an interim solution to some of the challenges. Another potential architectural solution includes specialized architectures for applications/models in the intelligent computing domain, one aspect of which includes abstract computational models inspired from the neuro/cognitive sciences.

Consequently in this …

Methodology For Developing A Functional Multiscale Architecture Model System Towards Future Integrated Circuits, Yamini Yadov

Dissertations and Theses

Detection of the biochemical species in the environmental pollution, industrial emission monitoring, medical diagnosis, public security, agriculture and a variety of industries has resulted in the emerging need for a generation of high density nanostructured sensor arrays. The fundamental two terminal and three terminal device components because of their potential for specificity eventually have to be integrated into miniaturized and portable nanoarray sensors. One of the key components in these nanosensors is the development of building functional building blocks that improve device performance capabilities. This research is focused on methodology for developing fundamental, functional, multiscale architecture model system for generating …

Spin Transport Studies In Nanoscale Spin Valves And Magnetic Tunnel Junctions, Sridhar Patibandla

Theses and Dissertations

Spintronics or electronics that utilizes the spin degree of freedom of a single charge carrier (or an ensemble of charge carriers) to store, process, sense or communicate data and information is a rapidly burgeoning field in electronics. In spintronic devices, information is encoded in the spin polarization of a single carrier (or multiple carriers) and the spin(s) of these carrier(s) are manipulated for device operation. This strategy could lead to devices with low power consumption. This dissertation investigates spin transport in one dimensional and two dimensional semiconductors, with a view to applications in spintronic devices.

Design Of An Ic Controller For A Light Emitting Diode Stack, Andrew Alleman

All Theses

An integrated circuit (IC) powering up to nine series connected high brightness light emitting diodes (HBLED's) was designed. The LED's are split into three groups by color (RGB), and the average current through each group is independently varied using a separate microprocessor in conjunction with the IC controller. Integrated comparators compare the voltage across each LED group with internally generated references to check for open or short circuit diodes. In the event of an open circuit failure, the IC controller switches in a SCR to bypass the open circuit device thus maintaining light output at reduced intensity.
Silvaco CAD tools …

Imaging Of Buried Utilities By Ultra Wideband Sensory Systems, Arun Prakash Jaganathan

Doctoral Dissertations

Third-party damage to the buried infrastructure like natural gas pipelines, water distribution pipelines and fiber optic cables are estimated at $10 billion annually across the US. Also, the needed investment in upgrading our water and wastewater infrastructure over the next 20 years is estimated by Environmental Protection Agency (EPA) at $400 billion, however, non-destructive condition assessment technologies capable of providing quantifiable data regarding the structural integrity of our buried assets in a cost-effective manner are lacking. Both of these areas were recently identified several U.S. federal agencies as 'critical national need'. In this research ultra wideband (UWB) time-domain radar technology …

A Detailed Look At The Omega-K Algorithm For Processing Synthetic Aperture Radar Data, Matthew A. Tolman

Theses and Dissertations

In this thesis, the Omega-k algorithm used for processing stripmap synthetic aperture radar (SAR) data is explored in detail. While the original Omega-k algorithm does not achieve the same SNR as a matched filter, a modification is presented which enables the algorithm to nearly achieve that SNR. It is shown that the focused point spread function obtained when the Omega-k algorithm is used differs in important ways from the output of a modified version of the matched filter. Spread out sidelobes and a stretched mainlobe are observed when the data is processed by the Omega-k algorithm. These differences may increase …

Modeling And Stability Analysis Of Nonlinear Sampled-Data Systems With Embedded Recovery Algorithms, Heber Herencia-Zapana

Electrical & Computer Engineering Theses & Dissertations

Computer control systems for safety critical systems are designed to be fault tolerant and reliable, however, soft errors triggered by harsh environments can affect the performance of these control systems. The soft errors of interest which occur randomly, are nondestructive and introduce a failure that lasts a random duration. To minimize the effect of these errors, safety critical systems with error recovery mechanisms are being investigated. The main goals of this dissertation are to develop modeling and analysis tools for sampled-data control systems that are implemented with such error recovery mechanisms. First, the mathematical model and the well-posedness of the …

Modeling Of Space-Charge-Limited Current Injection Incorporating An Advanced Model Of The Poole-Frenkel Effect, Satoshi Takeshita

All Theses

The current flow due to Space-Charge-Limited (SCL) emission is well known and the associated current-voltage power law relationship can be observed in many materials, particularly in insulators and semiconductors. Under an applied field, the space-charge effect occurs due to the carrier injection, and the resulting current due to the presence of the space-charge effect is referred to as SCL current. In the SCL current theory, the presence of localized traps in a material has a significant effect on the transport of injected carriers; however, in the first order SCL model, the trap barrier height is assumed to be constant for …

Range Precision Of Ladar Systems, Steven E. Johnson

Theses and Dissertations

A key application of Laser Detection and Ranging (LADAR) systems is measurement of range to a target. Many modern LADAR systems are capable of transmitting laser pulses that are less than a few nanoseconds in duration. These short-duration pulses provide excellent range precision. However, randomness in the detected laser signals places limits on the precision. The goal of this dissertation is to quantify the range precision limits of LADAR systems. The randomness in the time between photon arrivals, which is called shot noise, is discussed in depth. System-dependent noise sources such as dark current and detector gain variation are considered. …

Analysis And Design Of Multiphase Multi-Interleave Dc-Dc Converter With Input-Output Bypass Capacitor, Furqan Mubashir Saleemi

Master's Theses

The power requirements for the microprocessor have been increasing as per Moore's Law. According to International Technology Roadmap (ITRS), the Voltage Regulator Module (VRM) for the microprocessor will be 200 W(with 1V, 200A output) in 2010. With the VRMs topology of synchronous buck, serious technical challenges such as small duty cycle, high switching frequencies, and higher current demands, contribute to decreased power density and increased cost. This thesis proposes a Multiphase Multi-Interleave Buck topology to solve the technical challenges of powering future microprocessors. The critical design parameter values are selected using the theoretical design equations and calculations. The design is …

Investigation Into The Acupuncture And Meridian System, Jingong Pan

Dissertations

The Meridian system conceived by the ancient Chinese has been described and referenced for more than a thousand years. The Meridians meaning paths are the main trunks that run longitudinally within the body. The Meridian system consists of about 400 acupuncture nodes and 20 Meridian channels connecting most of these points. It deals with the routing and distribution of certain signals that may affect physiological functions. It integrates meridians, tissues and organs into a complex system.

Initially, modeling of the acupuncture system is investigated. The physical effect of injecting an acupuncture needle at a node is suggested by an equivalent …

A Two Dimensional Model Of Magnetic Field Assisted Assembly, Gaurev Devrani

Theses

A simplified model to simulate the magnetic field distribution for applications in magnetic field assisted assembly of semiconductor device structures, using commercial software (Vizimag), has been implemented. Solenoids have been utilized to serve as electromagnets that are responsible for the assembly process. Magnetic shielding techniques have been deployed to isolate the influence of one solenoid over another. These solenoids are used to move the devices that need to be placed in recesses within the substrate. The bottom of the devices and the recesses are coated with magnetic materials to facilitate the movement and placement of devices within the recesses in …

Accelerated Life Testing Of Electronic Revenue Meters, Venkata Chaluvadi

All Theses

Electricity meters are devices that continuously record electrical energy consumption. In the past, meters have been of electromechanical type and consisted windings and moving parts. Electromechanical meters tend to be bulky, less accurate and more susceptible to tampering. As with other aging power system infrastructure in the US, most electricity meters are around 40 years old and are nearing the end of their intended lifespan. Concerns over the accuracy of these electromechanical meters along with advances in technology have led to development of new electronic meters which have additional benefits such as light weight, tamper-proof mechanisms, harmonic detection and Advanced …

Vision-Based Detection, Tracking And Classification Of Vehicles Using Stable Features With Automatic Camera Calibration, Neeraj Kanhere

All Dissertations

A method is presented for segmenting and tracking vehicles on highways using a camera that is relatively low to the ground. At such low angles, 3D perspective effects cause significant appearance changes over time, as well as severe occlusions by vehicles in neighboring lanes. Traditional approaches to occlusion reasoning assume that the vehicles initially appear well-separated in the image, but in our sequences it is not uncommon for vehicles to enter the scene partially occluded and remain so throughout. By utilizing a 3D perspective mapping from the scene to the image, along with a plumb line projection, a subset of …

Statistical Methods For Polarimetric Imagery, Daniel A. Lemaster

Theses and Dissertations

Estimation theory is applied to a physical model of incoherent polarized light to address problems in polarimetric image registration, restoration, and analysis for electro-optical imaging systems. In the image registration case, the Cramer-Rao lower bound on unbiased joint estimates of the registration parameters and the underlying scene is derived, simplified using matrix methods, and used to explain the behavior of multi-channel linear polarimetric imagers. In the image restoration case, a polarimetric maximum likelihood blind deconvolution algorithm is derived and tested using laboratory and simulated imagery. Finally, a principal components analysis is derived for polarization imaging systems. This analysis expands upon …

Contingency Analysis Using Synchrophasor Measurements, Megan Vutsinas

All Theses

The rapid progress of synchrophasor technology greatly promotes many applications of wide-area measurement systems. Traditionally, contingency analysis is based on off-line studies conducted long in advance. This is becoming increasingly unreliable for real-time operations. New technologies, which rely on accurate, high resolution, and real-time monitoring of actual system conditions using phasor measurements are needed to support the real-time operations. In this research an algorithm is developed, using phasor measurements, that allows real-time analysis and correction of contingencies in power systems. The focus is specifically on overloaded lines. An off-line study performed with POWERWORLD software is used for contingency analysis, and …

Performance Analysis Of Multicarrier Code Division Multiple Access (Mc-Cdma) Systems, Pravinkumar Patil

Morehead State Theses and Dissertations

A thesis presented to the faculty of the College of Science and Technology at Morehead State University in partial fulfillment of the requirements for the Degree of Master of Science by Pravinkumar Patil on August 11, 2008.

Antennas And Arrays For Mobile Platforms -- Direct Broadcast Satellite And Wireless Communication, Songnan Yang

Doctoral Dissertations

Flexibility of any proposed communication links is becoming one of the most challenging features. Direct broadcasting satellite services, for example, will be greatly enhanced by providing service-on-the-move. This market is very demanding as it necessitates the development of a low cost, low profile antenna that can be mounted on top of SUVs and minivans, which is capable of continuously tracking the satellite. Another example is the wireless antennas for laptops and smart-phones, where the antennas should fit within an extremely small volume and should be capable of addressing many services over wide frequency range. In this dissertation, both DBS and …

Performance And Analysis Of Transfer Control Protocol Over Voice Over Wireless Local Area Network, Rajendra Patil

Morehead State Theses and Dissertations

A thesis presented to the faculty of the College of Science and Technology at Morehead State University in partial fulfillment of the requirements for the Degree Master of Science by Rajendra Patil in August of 2008.

Microwave Dielectroscopy Of Breast Tissue Phantoms In The 5.8-40 Ghz Range, Binh Tran

Electrical Engineering Undergraduate Honors Theses

Based on the high contrast in dielectric properties between the low-water-contain sample and the high-water-content one, we can determine whether the tissue sample is cancerous or normal. In order to make the measurement repeatable and convenient, some phantom materials, which have the same dielectric properties of human tissues, have been prepared. These phantom tissues are made from gelatin, water with honey syrup and Sodium Chloride (NaCl). In this project, we are going to measure and compare the dielectric properties of different types of phantom tissues by using focused beam antennas. The purpose of this project is to perform a systematic …

Architecture For Intelligent Power Systems Management, Optimization, And Storage., J. Chris Foreman

Electronic Theses and Dissertations

The management of power and the optimization of systems generating and using power are critical technologies. A new architecture is developed to advance the current state of the art by providing an intelligent and autonomous solution for power systems management. The architecture is two-layered and implements a decentralized approach by defining software objects, similar to software agents, which provide for local optimization of power devices such as power generating, storage, and load devices. These software device objects also provide an interface to a higher level of optimization. This higher level of optimization implements the second layer in a centralized approach …

Fiber Bragg Grating (Fbg) Based Chemical Sensor, Gopakumar Sethuraman

Theses and Dissertations

In this work, reagentless fiber optic-based chemical sensors for water quality testing were fabricated by coating fiber Bragg gratings with the glassy polymer cellulose acetate. With this polymeric matrix capable of localizing or concentrating chemical constituents within its structure, immersion of the coated grating in various chemical solutions causes the rigid polymer to expand and mechanically strain the glass fiber. The corresponding changes in the periodicity of the grating subsequently result in altered Bragg-reflected responses. A high-resolution tunable fiber ring laser interrogator is used to obtain room temperature reflectance spectrograms from two fiber gratings at 1550 nm and 1540 nm …

A Regularization Technique For The Analysis Of Photographic Data Used In Chemical Release Wind Measurements, Justin Ingersoll

All Theses

The neutral winds are a key parameter in the electrodynamics of the ionosphere. The available techniques for measuring vertical neutral wind profiles, especially with good height resolution, are extremely limited. This is especially true with sounding rocket flights as it is not practical to take direct measurements of neutral winds with onboard instruments. Chemical releases from sounding rockets, however, allow such measurements by providing a tracer of the motion of the neutral atmosphere at altitudes in the mesosphere and lower thermosphere (MLT). The resulting chemiluminescent trail is typically photographed from two or more locations to track neutral motions. Triangulation based …

Automated State Change Detection Of A Gaussian Distributed Signal, Anirudh Singh

All Theses

This work presents a novel approach to detect a change in the state of a signal. The hypothesis is that in a given state, the values of a signal vary in a sub-part of a Gaussian distribution. By modeling a signal using a sub-part of the Gaussian distribution, a quantitative value representing the state of the signal is obtained. This value is monitored with time to detect a change in the state of the signal. The proposed algorithm is implemented and tested on data obtained from a related research.

Experimental Framework For The Position Control Of Magnetic Microfibers, Sriram Ravindren

All Theses

Magnetic microfibers have been developed in recent years with potential applications to a large number of fields, from MEMS to microfluidics to bio-chemical analyses. Magnetic microfibers based on polymer material like polypropylene and cellulose has been developed at Clemson University that are hollow cylindrical filaments internally coated with superparamagnetic nanoparticles. This internal coating provides the fiber with magnetic properties that allow them to be externally controlled using magnetic fields from a distance. These fibers can align with the external magnetic fields under constraints imposed by elastic properties and boundary conditions. Current work in this field is primarily focused on the …