Engineering Commons^™

Multi-Sensor Data Fusion Using Geometric Transformations For The Nondestructive Evaluation Of Gas Transmission Pipelines, Philip James Kulick

Theses and Dissertations

Nondestructive evaluation (NDE) plays a vital component in the operation and maintenance of large infrastructure such as gas transmission pipelines, nuclear power plants, aircraft, bridges and highways, etc. As this infrastructure continues to age it is essential that the inspection techniques reliably and accurately predict the integrity of these systems. No single NDE method is capable of inspecting all types of anomalies and extracting all required information – a combination of methods must be used and the resulting data fused. Moreover, newer systems that are developed are often made of composite materials that include metals and dielectrics. One interrogation modality …

Spatially Varying Threshold Models For The Automated Segmentation Of Radiodense Tissue In Digitized Mammograms, Richard Edson Eckert Iii

Theses and Dissertations

The percentage of radiodense (bright) tissue in a mammogram has been correlated to an increased risk of breast cancer. This thesis presents an automated method to quantify the amount of radiodense tissue found in a digitized mammogram. The algorithm employs a radial basis function neural network in order to segment the breast tissue region from the remainder of the X-ray. A spatially varying Neyman-Pearson threshold is used to calculate the percentage of radiodense tissue and compensate for the effects of tissue compression that occurs during a mammography procedure. Results demonstrating the efficacy of the technique are demonstrated by exercising the …

Development Of An Augmented Haptic Control For In-Vehicle Law Enforcement Applications, Edward R. Guest Iii

Theses and Dissertations

Typical police vehicles are filled with as much technology as the department can afford. Everything from the newest digital camera system to a simple entertainment radio is within the reach of an officer. Currently, most of these systems are installed without any consideration toward the other systems or the interaction required between the driver and the car. The lack of a systems approach in the installation has spawned a project to look at the safety and overall system installation in the New Jersey State Police vehicles.

The research presented in this thesis suggests consolidation of the various controls into one …

Hdl Implementation Of A Controller Area Network Node, Anthony Richard Marino

Theses and Dissertations

With increasing technology inside automobiles, especially law enforcement vehicles, there is a growing need for centralized wiring and device interconnection methods. Each new technology, such as GPS navigation units and in-vehicle video systems, includes a corresponding wiring harness that needs installation. The summation of all these hardwired technologies leads to large volumes of wire that negatively affect safety, power demands, and future design opportunities. A new trend among automotive manufacturers is to design and implement innovative networks that allow for shared communications between technologies.

This thesis presents the design, development, and implementation of an in-vehicle network that will centralize connections …

Wind Scatterometry With Improved Ambiguity Selection And Rain Modeling, David W. Draper

Theses and Dissertations

Although generally accurate, the quality of SeaWinds on QuikSCAT scatterometer ocean vector winds is compromised by certain natural phenomena and retrieval algorithm limitations. This dissertation addresses three main contributers to scatterometer estimate error: poor ambiguity selection, estimate uncertainty at low wind speeds, and rain corruption. A quality assurance (QA) analysis performed on SeaWinds data suggests that about 5% of SeaWinds data contain ambiguity selection errors and that scatterometer estimation error is correlated with low wind speeds and rain events.

Ambiguity selection errors are partly due to the "nudging" step (initialization from outside data). A sophisticated new non-nudging ambiguity selection approach …

Satellite Scatterometers: Calibration Using A Ground Station And Statistical Measurement Theory, Peter Kenneth Yoho

Theses and Dissertations

Satellite scatterometers have recently gained popularity due to their unique ability to measure global geophysical data on a daily basis. Increased interest in scatterometry mandates improved design and calibration of these instruments. This dissertation presents new techniques for scatterometer calibration and addresses issues related to the design of future instruments and applications. First, the use of a calibration ground station is considered. A new methodology is established for calibration of SeaWinds, NASA's current scatterometer, using a receive-only ground station. Principles of the methodology are implemented, new analysis techniques developed, and important results obtained for instrument timing, frequency, power, position, and …

Analytical Modeling Of High Performance Reconfigurable Computers: Prediction And Analysis Of System Performance., Melissa C. Smith

Doctoral Dissertations

The use of a network of shared, heterogeneous workstations each harboring a Reconfigurable Computing (RC) system offers high performance users an inexpensive platform for a wide range of computationally demanding problems. However, effectively using the full potential of these systems can be challenging without the knowledge of the system’s performance characteristics. While some performance models exist for shared, heterogeneous workstations, none thus far account for the addition of Reconfigurable Computing systems. This dissertation develops and validates an analytic performance modeling methodology for a class of fork-join algorithms executing on a High Performance Reconfigurable Computing (HPRC) platform. The model includes the …

Design Of A Wide-Swing Cascode Beta Multiplier Current Reference, Bradley David Miser

Masters Theses

This thesis presents a study of the design of a wide-swing, cascode β multiplier current reference to be used as a biasing circuit. The current reference has been fabricated in a 0.5mm CMOS technology. First, a review of wide-swing cascode current mirrors and current-source self-biasing is covered. Then, the process of designing a current reference that is both wide-swing and has high output resistance is presented. Simulation and measurement results from the current reference are detailed. Improvements upon the current reference are also suggested.

Performance Of Bit Error Rate And Power Spectral Density Of Ultra Wideband With Time Hopping Sequences., Joseph Martin Peek

Masters Theses

This thesis focuses on several modulation methods for an ultra wideband (UWB) signal. These methods are pulse position modulation (PPM), binary phase shift keying (BPSK), on/off key shifting (OOK), and pulse amplitude modulation (PAM). In addition, time hopping is considered for these modulation schemes, where the capacity per time frame of time hopping PPM is studied using different spreading ratios. This thesis proves that with the addition of time hopping to all types of modulated UWB signals, the performance of power spectral density improves in all aspects, despite the increase of data per time frame. Note that despite the increase …

Silicon Carbide Gto Thyristor Loss Model For Hvdc Application, Madhu Sudhan Chinthavali

Masters Theses

With the increase in use of power electronics in transmission and distribution applications there is a growing demand for cost effective and highly efficient converters. Most of the utility applications have power electronics integrated in the system to improve the efficiency and functionality of the existing system. The development of semiconductor devices is vital for the growth of power electronic systems. Modern technologies like voltage source converter (VSC) based HVDC transmission has been made possible with the advent of power semiconductor devices like IGBT and GTO thyristor with their high power handling capability. Various material limitations of silicon power semiconductor …

A Preliminary Study Of The Effects Of Exposure To A One Atmosphere Uniform Glow Discharge Plasma (Oaugdptm) On The Surface Energy And Strength Of Meltblown And Nanofiber Fabrics, Weiwei Chen

Masters Theses

Electrohydrodynamic (EHD) methods have recently been developed to electrospin nano-scale non-woven webs and to improve their properties by exposure to the One Atmosphere Uniform Glow Discharge Plasma (OAUGDPä), as a collaborative effort by the UT Plasma Sciences Laboratory and the UT Textiles and Nonwovens Development Center (TANDEC).

Nanofiber webs are made by the electrospinning (ES) process, which uses the electrostatic force to spin fibers from a polymer solution or melt. Digitized SEM images show that the fiber diameters range from 10 nm to several microns. Such nanofiber fabrics have a significantly higher tensile strength than meltblown (MB) webs of the …

Silicon-On-Insulator Power Management Integrated Circuit For Thin-Film Solid-State Lithium-Ion Micro-Batteries, Jeremy Ross Jackson

Masters Theses

This thesis presents the design and implementation of a power management integrated circuit (IC) that is capable of both current and voltage charging thin-film, solid-state, lithium-ion micro-batteries. The power management system has been fabricated using a single-poly, 0.35-ìm, partially-depleted, silicon-on-insulator process (PD-SOI). The system contains a temperature stable current charger (current generator and a 4-bit current-mode DAC), a regulated voltage supply (voltage amplifier), and a voltage monitoring circuit (2-bit flash ADC). Experimental results of the first version of the power management system show proper functionality was obtained. The current charger produced a 2% worst-case variation in output current over the …

Virtual And Augmented Reality Simulation Of Chattanooga Creek, Sirisha Vadlamudi

Masters Theses

Virtual reality involves reproducing all the details of a physical object or environment that has to be simulated in virtual space. Augmented reality is the mixing of computer-generated information with the user’s view of the real world. Augmented reality is an alternative for virtual reality. This thesis presents the interactive virtual reality simulation and augmented reality simulation of Chattanooga Creek in Chattanooga, TN. The augmented reality part involves implementation of the basic concept of augmenting the virtual graphics to the real world.

Swift Electro-Optic Modulator, Geofrey Craig Harston

Theses and Dissertations

The Silicon Wafer Integrated Fiber Technology, SWIFT, is a novel platform for the development of photonic devices. SWIFT is comprised of an optical fiber, specifically a D-fiber in this work, embedded into a V-groove etched into a silicon wafer. This provides a method to secure the fiber and allows the use of standard semiconductor industry equipment and techniques in latter processing for device fabrication.

The SWIFT platform is used as the basis for the development of a polarimetric in-fiber electro-optic modulator. The modulator is based on the application of a nonlinear optical polymer, NLOP, film into the evanescent field of …

Polymer-Based Capacitors, Junction Field -Effect Transistors, And A Follower Circuit By Lithography, Self -Assembly, And Ink -Jet Printing Techniques, Yuxin Liu

Doctoral Dissertations

The study of organic materials to create field-effect transistors has recently emerged and is gaining much interest. All-polymer electronic devices are currently in their infancy, like semiconductor devices when they first appeared. As a result, current performance of these devices is in no way comparable to the state-of-the-art semiconductor devices. However, all-polymer devices have a few possible appealing advantages. First, all polymer devices have the potential for low-cost fabrication due to their ease of manufacturability, with fewer and simpler processing steps compared with solid-state semiconductor devices. Secondly, polymer devices offer the ability of material flexibility. Lastly, polymer devices may prove …

Theory, Design, And Fabrication Of Diffractive Grating Coupler For Slab Waveguide, Kevin Randolph Harper

Theses and Dissertations

This thesis presents the theory design and fabrication of a diffractive grating coupler. The first part of the design process is to choose the period of the grating coupler based on the desired coupling angle. The second part of the design process is to choose the geometry of the grating that gives maximum coupling efficiency based on rigorous analyses.

The diffraction gratings are fabricated by recording the interference between two waves in photoresist. The waveguide is fabricated from silicon nitride that is deposited by chemical vapor deposition. The diffraction grating recording assembly is described along with the grating coupler fabrication …

Mobility Modeling And Management For Next Generation Wireless Networks, Woo-Jin Choi

Dissertations

Mobility modeling and management in wireless networks are the set of tasks performed in order to model motion patterns, predict trajectories, get information on mobiles' whereabouts and to make use of this information in handoff, routing, location management, resource allocation and other functions.

In the literature, the speed of mobile is often and misleadingly referred to as the level of mobility, such as "high" or "low" mobility. This dissertation presents an information theoretic approach to mobility modeling and management, in which mobility is considered as a measure of uncertainty in mobile's trajectory, that is, the mobility is low if the …

Performance Evaluation For Communication Systems With Receive Diversity And Interference, Debang Lao

Dissertations

Optimum combining (OC) is a well-known coherent detection technique used to combat fading and suppress cochannel interference. In this dissertation, expressions are developed to evaluate the error probability of OC for systems with multiple interferers and multiple receiving branches. Three approaches are taken to derive the expressions. The first one starts from the decision metrics of OC. It facilitates obtaining closed-form expressions for binary phase-shift keying modulation. The second approach utilizes the moment generating function of the output signal to interference plus noise ratio (SINR) and results in expressions for symbol and bit error probability for multiple phaseshift keying modulation. …

Capacity, Coding And Interference Cancellation In Multiuser Multicarrier Wireless Communications Systems, Christian Ibars Casas

Dissertations

Multicarrier modulation and multiuser systems have generated a great deal of research during the last decade. Orthogonal Frequency Division Multiplexing (OFDM) is a multicarrier modulation generated with the inverse Discrete Fourier Transform, which has been adopted for standards in wireless and wire-line communications. Multiuser wireless systems using multicarrier modulation suffer from the effects of dispersive fading channels, which create multi-access, inter-symbol, and inter-carrier interference (MAI, ISI, ICI). Nevertheless, channel dispersion also provides diversity, which can be exploited and has the potential to increase robustness against fading. Multiuser multi-carrier systems can be implemented using Orthogonal Frequency Division Multiple Access (OFDMA), a …

Method For Theoretically Determining The Locus And Location Of The Transmission Zeros In Microwave Filter Networks, Keehong Um

Dissertations

This dissertation presents a theoretical investigation of a practical method to determine quantitatively the locations and loci of complex transmission zeros (TZ's) of positively and negatively cross-coupled RF or microwave bandpass filter networks.

Bandpass filters can be effectively designed by adjusting the locations of TZ's in the complex s-domain. To locate TZ's, this practical method uses chain matrices for subsystems (discrete parts of the network) of the filter network, and can be extended to other types of filters with cross-coupled sections.

An important result is that a complex doublet, triplet and/or quadruplet, (one-, two-, or four-pairs) of TZ's are shown …

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

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 …

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

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

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

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, …

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 …

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 …

Development And Verification Of Parameterized Digital Signal Processing Macros For Microelectronic Systems, Adam Robert Miller

Masters Theses

Digital system design is a broad field that is growing every day. As technology grows, the complexity of systems grows also, which leads to longer design times. A Design-for-reuse policy can decrease design time by building flexibility into designs as they are created. By creating parameterized macros, they are more likely to be reused. Verifying the capabilities of macros is also important, and testing should be incorporated into each step of the design process. In this thesis, designing parameterized macros is discussed, with a Complex Fast Fourier Transform presented as an example of a complex algorithm, and three different Rounder …

Design And Verification Of The Data Encryption Standard For Asics And Fpgas, Xiaoquan Fu

Masters Theses

Encryption and decryption in a communication channel are used to provide security. In this thesis, the Data Encryption Standard (DES) is implemented with both FPGAs and ASICs. Different versions of FPGAs from different synthesis tools are compared. For ASIC implementation, the design space is explored to compile the design with different optimization targets like size, speed and power. Physical realizations of the design are obtained with Cadence tools. Simulations are made at each level to verify the implementations.