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Full-Text Articles in Electrical and Electronics

Elastic Brain Image Registration Using Mutual Information, Srisheela Devabhaktuni Aug 2003

Elastic Brain Image Registration Using Mutual Information, Srisheela Devabhaktuni

Theses

Image Registration is the determination of a geometrical transformation that aligns points in one image of an object with corresponding points in another image. The source image is geometrically transformed to match the target image. The geometric transformation can be rigid or non-rigid. Rigid transformations preserve straight lines and angles between straight lines. The basic rigid transformations are rotation, scaling and translation.

In this thesis non-rigid registration using B-splines is the method being used to take into account the elastic change in the brain structure. The B-spline equation is a type of curved transformation that does not preserve the straightness …


Study Of Mosfet Degradation Under Substrate Injection And Hot Carrier Degradation, Bhawar S. Patel Aug 2003

Study Of Mosfet Degradation Under Substrate Injection And Hot Carrier Degradation, Bhawar S. Patel

Theses

With continued scaling of MOSFET's, the reliability of thin gate oxides is becoming increasingly important. Degradation issues due to fabrication technology may result in misinterpretation unless the actual physical situation arising at source, drain, gate and substrate of a transistor during processing is understood. This degradation is prominent in plasma processing due to wafer charging which occurs due to the reactive ions in the plasma. The voltages developed at source and drain junctions, depending upon polarity relative to the substrate cause the source and drain junctions to be forward biased or reverse biased. Keeping in view this type of physical …


Co-Operative Location Updates For Mobile Nodes For Cellular Networks, Samir Shah Aug 2003

Co-Operative Location Updates For Mobile Nodes For Cellular Networks, Samir Shah

Theses

In current pure cellular networks, each and every mobile node updates it's location to the particular base station separately following certain algorithms, say timer based, mobility based or both. For the next generation wireless networks, which we can consider as a highly dense network, such location update algorithms prove to be very costly in the terms of overall location update traffic to the base station and average battery usage by each mobile node for location updates due to large number of mobile nodes for particular base station area.

Instead of using such one-to-one link for location updates, this report describes …


Photonic Crystals Composed Of Thick Inductive And Capacitive Meshes, Jay Shah Aug 2003

Photonic Crystals Composed Of Thick Inductive And Capacitive Meshes, Jay Shah

Theses

The transmission properties of metal meshes are studied for single meshes, photonic double layers and photonic crystals. Simulations are performed with the Flomerics Micro-Stripes program for light of infrared and millimeter wavelengths. The Micro-Stripes program solves Maxwell's equations numerically and, for simulations of the transmittance of metal meshes, has been proven as good as an experiment. Input data are the geometrical parameters, the indices of refraction and the conductivity, chosen according to the Drude model. The light is assumed to be at normal incidence and the simulation results are compared with experiments.

Single layers of inductive meshes are studied for …


A Combined Channel-Modified Adaptive Array Mmse Canceller And Viterbi Equalizer, Richard M. Friedman Aug 2003

A Combined Channel-Modified Adaptive Array Mmse Canceller And Viterbi Equalizer, Richard M. Friedman

Theses

In this thesis, a very simple scheme is proposed which couples a maximum-likelihood sequence estimator (MLSE) with a X-element canceller. The method makes use of the MLSE's channel estimator to modify the locally generated training sequence used to calculate the antenna array weights. This method will increase the array's degree of freedom for interference cancellation by allowing the dispersive, desired signal to pass through the array undisturbed. Temporal equalization of the desired signal is then accomplished using maximum-likelihood sequence estimation. The T-spaced channel estimator coefficients and the array weights are obtained simultaneously using the minimum mean square error criteria. The …


Deposition And Characterization Of Laser-Ablated Silicon, Wenwen Luo Aug 2003

Deposition And Characterization Of Laser-Ablated Silicon, Wenwen Luo

Theses

Laser ablation is a powerful thin film deposition and material processing technology. In the Nonlinear Nanostructure Lab at NJIT, silicon films deposited by laser ablation have been studied for the potential applications in nonlinear optoelectronic devices. The previous studies have suggested that the deposited silicon has a hexagonal symmetry, being a polymorph of silicon that previously has been obtained only at very high pressure. This thesis is part of the continuous study and characterization of this new structure. The objective of the research was to gain better understanding of the hexagonal silicon properties as well as the mechanism that lead …


Service Differentiation In Multihop Wireless Packet Networks, Ilker Onat Aug 2003

Service Differentiation In Multihop Wireless Packet Networks, Ilker Onat

Theses

This work explores the potential of link layer scheduling combined with MAC layer prioritization for providing service differentiation in multihop wireless packet networks. As a result of limited power, multihop characteristic and mobility, packet loss ratio in wireless ad hoc networks tends to be high compared to wireline and one-hop mobile data networks. Therefore, for wireless ad hoc networks, DiffServ-like distributed service differentiation schemes are more viable than hard QoS solutions, which are mainly designed for wireline networks. The choice and implementation of proper queuing and scheduling methods, which determine how packets will use the channel when bandwidth becomes available, …


Transport Properties Of Nc-Si / A-Sio2 Superlattices And Their Applications In Non-Volatile Memory, Lakshmi Susmitha Koneru Aug 2003

Transport Properties Of Nc-Si / A-Sio2 Superlattices And Their Applications In Non-Volatile Memory, Lakshmi Susmitha Koneru

Theses

The dc current-voltage characteristics, ac conductivity, equivalent capacitance, photocurrent transients of the n-Si/nanocrystalline-Si/amorphous-SiO2/Al heterostructure were measured in a wide range of illumination intensities for temperatures from 4.2 K to 300 K. Electrical transport properties of the nanocrystalline-Si/amorphous-SiO2 superlattices were discussed. The observed domination of the electron component at negative bias and of the hole component at positive bias above 0.7 V in a dc current allows to separate transport features of electrons and holes in a nc-Si/a-SiO2 superlattices. Transport of electrons is thermally activated if potential barrier at c-Si/SL interface of 70 meV is suppressed and …


Spatio-Temporal Correlation Models For Indoor Mimo Channels, Kaustubha Raghukumar May 2003

Spatio-Temporal Correlation Models For Indoor Mimo Channels, Kaustubha Raghukumar

Theses

Accurate modeling of the spatio-temporal cross-correlation between the subchannels of a multiple-input multiple-output (MIMO) channel is an important prerequisite of multi-element antenna system design. In this thesis, a new model for indoor MIMO channels is proposed, and a closed form expression for the spatio-temporal cross-correlation function is derived. This new analytical correlation expression includes many physical parameters of interest such as the angle-of-arrivals at the base station and the user, the associated angle spreads, and other parameters, in a compact form. Comparison of this model with narrowband indoor MIMO data collected at Brigham Young University exhibits the utility of the …


Characterization And Mapping Of Crystal Defects In Silicon Carbide, Ejiro Emorhokpor May 2003

Characterization And Mapping Of Crystal Defects In Silicon Carbide, Ejiro Emorhokpor

Theses

Silicon carbide (SiC) is a semiconductor with attractive properties, such as a wide bandgap (3. 26 eV), high dielectric strength, and high thermal conductivity that make it suitable for high power, highspeed electronic devices. A major roadblock to its wider application is the presence of defects, particularly micropipes and dislocations, in SiC wafers produced today and decreasing density of these defects is the most important challenge of the industry. The goal of this thesis was to design, build and test a system for detection and analysis of the defects in SiC wafers. The system is based on the reflection optical …


Low-Power Transceiver Design For Mobile Wireless Chemical Biological Sensors, Harshavardhan Reddy Sripuram May 2003

Low-Power Transceiver Design For Mobile Wireless Chemical Biological Sensors, Harshavardhan Reddy Sripuram

Theses

The design of a smart integrated chemical sensor system that will enhance sensor performance and compatibility to Ad hoc network architecture remains a challenge. This work involves the design of a Transceiver for a mobile chemical sensor. The transceiver design integrates all building blocks on-chip, including a low-noise amplifier with an input-matching network, a Voltage Controlled Oscillator with injection locking, Gilbert cell mixers, and a Class E Power amplifier making it as a single-chip transceiver. This proposed low power 2GHz transceiver has been designed in TSMC 0.35~lm CMOS process using Cadence electronic design automation tools. Post layout HSPICE simulation indicates …


Improving The Process Of Laser Retinal Eye Surgery Using Electro Static Micro Mirrors, Narashiman Chakravarthy May 2003

Improving The Process Of Laser Retinal Eye Surgery Using Electro Static Micro Mirrors, Narashiman Chakravarthy

Theses

This thesis describes an improved system for laser eye surgery. The system incorporates hardware based image matching and MEMS micromirrors for feedback control of laser positioning on the eye. Many benefits are described in this thesis, such as nulling out eye movement, tracking laser firing history, enabling precise control of laser firing locations and preventing firing accidents. The aim of this work is to frame this improved laser surgery concept and prove the principle of various components of the system. A featured accomplishment is the modeling and simulation of a prototype microcontroller using VHDL that may be incorporated as part …


Sparse Matrix Product Implementation On Field Programmable Gate Arrays (Epgas), Amit Mahendra Sheth May 2003

Sparse Matrix Product Implementation On Field Programmable Gate Arrays (Epgas), Amit Mahendra Sheth

Theses

If dense matrix multiplication algorithms are used with sparse matrices, they can result in a large number of redundant calculations, as numerous elements in sparse matrices are zero valued, thus available resources and time may be wasted. The algorithm discussed here aims to take advantage of the sparseness of the matrices by multiplying only nonzero elements.

The NIOS development board from Altera is used for implementing the above algorithm. First a sequential program in the C programming language is downloaded onto the FPGA and run by the NIOS soft-processor. Then the same board is also used for a parallel implementation …


Firewall Interface For Java Ftp Smtp And Http Servers, Ratan Kumar Erukulla Jan 2003

Firewall Interface For Java Ftp Smtp And Http Servers, Ratan Kumar Erukulla

Theses

The objective of my thesis is to develop a firewall interface for FTP, HTTP and SMTP servers. A firewall interface is a graphical user interface (GUI) to configure the properties of the server. Using this interface, we can spy a user, block and unblock the IP address of a client, display statistics of user and server. We can track all the user actions while he is connected to the server. These actions are logged and based on the log data we can deny access to users performing illegal operations. All the servers and interfaces are written in Java. Java was …


An Interface Chip For Saw Based Sensor In An Ad-Hoc Network, Yagneshwara Ramakrishna Vadapalli Jan 2003

An Interface Chip For Saw Based Sensor In An Ad-Hoc Network, Yagneshwara Ramakrishna Vadapalli

Theses

The design of a smart integrated chemical sensor system that will enhance sensor performance and compatibility to ad hoc network architecture remains a challenge. This work involves the design of an interface chip for a Surface Acoustic Wave (SAW) based chemical sensor where the sensor reflects the RF input and introduces a time delay proportional to the concentration of the vapors absorbed by it. The interface chip detects the frequency shift as a function of the chemical species absorbed by the sensor and alerts the ad hoc network controller when a monitored parameter exceeded some threshold, based on local processing …


Vlsi Design Of Stability Routing Protocol For Sensors In Wireless Mobile Ad-Hoc Networks, Vishnu M. Mandava Jan 2003

Vlsi Design Of Stability Routing Protocol For Sensors In Wireless Mobile Ad-Hoc Networks, Vishnu M. Mandava

Theses

This thesis gives a detailed description of the Application specific integrated circuit (ASIC) design of Stability routing protocol for sensors in mobile ad-hoc networks. The Stability routing protocol is based on the signal strength and position components during data transmission while considering sensors in an ad-hoc network. A general ad-hoc network has unpredictable and variable mobility patterns therefore the signal strength criteria is adopted for routing. Signal strength criteria has been proved to be efficient for communication between the mobile nodes without any data loss. In this thesis an architecture for a processor implementing stability routing protocol for effective communication …


Dynamically Biased Radio Frequency Power Amplifier, Tom Twomey Jan 2003

Dynamically Biased Radio Frequency Power Amplifier, Tom Twomey

Theses

With the current trend in mobile communications towards more complex modulation schemes to enhance spectral efficiency, the design of RF power amplifiers is the subject of considerable interest and research. The newer more spectrally efficient modulation schemes require a much higher level of linearity due to the non-constant level of their signal envelope. A variable envelope signal would in non-linear amplifiers lead to unacceptable levels of distortion. Linear amplifiers solve this problem at the cost of significant loss of efficiency. With the evolution towards more spectrally efficient modulation schemes, the trade off between linearity and power efficiency has become more …


Automated Distribution And Management Of Software And Hardware Configurations For Heterogeneous Wireless Devices, Grainne Foley Jan 2003

Automated Distribution And Management Of Software And Hardware Configurations For Heterogeneous Wireless Devices, Grainne Foley

Theses

The continuing evolution of wireless networks and services has increased the complexity and diversity of wireless networks and devices, placing significant emphasis on the need for flexible device configuration management. Widely varying wireless technologies currently operate independently worldwide, making global wireless network access for the mobile user confusing and unwieldy. New technologies, network access methodologies and improved services further obscure the evolving environment. The focus of effort for this thesis is the development of a system to automate the distribution and management of software and hardware configurations that enable different levels of wireless device reconfiguration. The scope of investigation will …


Performance Evaluation Of Sip Based Services In Umts, Maria Isabel Pous Fenollar Jan 2003

Performance Evaluation Of Sip Based Services In Umts, Maria Isabel Pous Fenollar

Theses

With ever increasing penetration of IP technologies and the tremendous growth in wireless data traffic, the wireless industry is evolving the mobile core networks towards IP technology. The 3rd Generation Partnership Project (3GPP) is specifying an IP Multimedia Core Network Sub-System (IMS) in UMTS Release 5 and Release 6, which is adjunct to the UMTS GPRS core network. This IP-based network will allow mobile operators to provide commonly used Internet applications to wireless user. The UMTS IMS uses the Internet Engineering Task Force (IETF) defined text based Session Initiation Protocol (SIP), to control a wide range of anticipated IP-based services …


Multiple Model Control With Intelligent Switching To Ensure Robustness To Process Variations., Peter Cunningham Jan 2003

Multiple Model Control With Intelligent Switching To Ensure Robustness To Process Variations., Peter Cunningham

Theses

One of the most popular approaches for dealing with process that undergo large variations with time, of late, is the multiple model approach. This method has considerable intuitive appeal and has received widespread dissemination in academia. Numerous successful simulations have been reported although few real-time results have been published. The principal contribution of this thesis is the application of the multiple model control scheme in real-time.

A number of practical concepts that enable the use of multiple model control in real-time are discussed. Many of these issues arose when the multiple model control scheme was applied to a laboratory scale …


Hot Carrier Reliability Of Lateral Dmos Transistors In Power Process Applications, Vicky O'Donovan Jan 2003

Hot Carrier Reliability Of Lateral Dmos Transistors In Power Process Applications, Vicky O'Donovan

Theses

The purpose of this study is to investigate and validate the mechanism of hot carrier degradation of the LDMOS device. The LDMOS device is a new technology to Analog Devices, and a relatively new topic to the semiconductor industry, evident from the limited published research in the field. A prerequisite for device release on a product in the market place, is comprehensive hot carrier reliability testing, as hot carrier degradation has evolved as one of the foremost concerns in submicron devices. Both the high voltage and the structural difference of the LDMOS device, from standard MOSFET device, pose a hot …


Adaptive Baseband Predistortion For Rf Power Amplifier Linearization., Laura Faus-Ferrer Jan 2003

Adaptive Baseband Predistortion For Rf Power Amplifier Linearization., Laura Faus-Ferrer

Theses

In order to make use of spectrally efficient linear modulation methods for mobile communications, it is necessary to linearise the underlying RF power amplifier (PA). A number of techniques for linearizing a PA have been studied, focusing on the Adaptive Baseband Predistortion. The work is centred on the research concentrates on the analysis of different algorithms, their simulation using MatLab, and implementation of a predistorter as a subsystem of a prototype Cartesian based transmitter.

The thesis describes the typical architecture of a transceiver with an emphasis on the nonlinear analysis. Cavers’ algorithm has been examined in terms of its computational …


Modern Control Techniques For Induction Machines In High-Performance Adjustable-Speed Drives, Pat Cronin Jan 2003

Modern Control Techniques For Induction Machines In High-Performance Adjustable-Speed Drives, Pat Cronin

Theses

Induction Motors (IM’s) are increasingly being considered for and used in high-performance motor drive (HPMD) systems. Their application has only gained acceptance since the 1970’s with the advent of vector control, microprocessors and improvements in power converter technology. D.C. motors were traditionally the preferred choice in HPMD systems. The main reasons for IM acceptance in HPMD systems are ruggedness, durability, low maintenance, cost, and small size by comparison with D.C. motors.

Alternating current asynchronous motors of the IM type are considered to be the universal workhorses of the manufacturing industry. It has been estimated that they are used in seventy …


Design For Signal Integrity In High Frequency, High Density Circuit Boards, Juan Manuel Talavera Martinez Jan 2003

Design For Signal Integrity In High Frequency, High Density Circuit Boards, Juan Manuel Talavera Martinez

Theses

The electronics market is continually seeking fast and small high performance products. The clock frequency in computer systems is often above 2GHz and new generations of laptops have considerably reduced in size. These features make printed circuit board (PCB) design more difficult than in the past.

This thesis is an investigation of the current design of high speed PCB. The complexity of this type of circuit makes the designer needs an extensive knowledge of the techniques used to generate a reliable signalling, in other words, signal integrity. To achieve this objective, the design community has to overcome several problem related …