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Full-Text Articles in Engineering

Improvement Of Silicon Oxide Quality Using Heat Treatment, Lei Han Jan 2012

Improvement Of Silicon Oxide Quality Using Heat Treatment, Lei Han

Theses and Dissertations--Electrical and Computer Engineering

In decades, the tremendous development of integrated circuits industry could be mostly attributed to SiO2, since its satisfactory properties as a gate dielectric candidate. The effectivity of SiO2 has been challenged since dielectric layer was scaled down below 3nm, when the gate leakage current of SiO2 became unacceptable. Institution to silicon-based CMOS techniques were proposed, but they have their own limitations. Nowadays, materials with high dielectric constants are mainstream gate dielectric materials in industry, but a SiO2 interfacial layer is still necessary to avoid gap between gate dielectric layer and Si substrate, and to minimize interface trap charges. In this …


Comparing Acoustic Glottal Feature Extraction Methods With Simultaneously Recorded High-Speed Video Features For Clinically Obtained Data, Sean Michael Hamlet Jan 2012

Comparing Acoustic Glottal Feature Extraction Methods With Simultaneously Recorded High-Speed Video Features For Clinically Obtained Data, Sean Michael Hamlet

Theses and Dissertations--Electrical and Computer Engineering

Accurate methods for glottal feature extraction include the use of high-speed video imaging (HSVI). There have been previous attempts to extract these features with the acoustic recording. However, none of these methods compare their results with an objective method, such as HSVI. This thesis tests these acoustic methods against a large diverse population of 46 subjects. Two previously studied acoustic methods, as well as one introduced in this thesis, were compared against two video methods, area and displacement for open quotient (OQ) estimation. The area comparison proved to be somewhat ambiguous and challenging due to thresholding effects. The displacement comparison, …


Smart Grid Communications, Christopher W. Asbery Jan 2012

Smart Grid Communications, Christopher W. Asbery

Theses and Dissertations--Electrical and Computer Engineering

Smart grid technologies are starting to be the future of electric power systems. These systems are giving the utilities detailed information about their systems in real time. One of the most challenging things of implementing smart grid applications is employing the communications into the systems. Understanding the available communications can help ease the transition to these smart grid applications. Many of the utility personnel are spending too much time trying to figure out which communication is better for their application or applications. So this thesis presents the different communication types available with discussing the different attributes in which these communication …


Root Locus Techniques With Nonlinear Gain Parameterization, Brandon Wellman Jan 2012

Root Locus Techniques With Nonlinear Gain Parameterization, Brandon Wellman

Theses and Dissertations--Mechanical Engineering

This thesis presents rules that characterize the root locus for polynomials that are nonlinear in the root-locus parameter k. Classical root locus applies to polynomials that are affine in k. In contrast, this thesis considers polynomials that are quadratic or cubic in k. In particular, we focus on constructing the root locus for linear feedback control systems, where the closed-loop denominator polynomial is quadratic or cubic in k. First, we present quadratic root-locus rules for a controller class that yields a closed-loop denominator polynomial that is quadratic in k. Next, we develop cubic root-locus rules …


Metallic Patterning Using An Atomic Force Microscope Tip And Laser-Induced Liquid Deposition, Carlos Andrés Jarro Sanabria Jan 2012

Metallic Patterning Using An Atomic Force Microscope Tip And Laser-Induced Liquid Deposition, Carlos Andrés Jarro Sanabria

Theses and Dissertations--Electrical and Computer Engineering

The development of nanoscale patterns has a vast variety of applications going from biology to solid state devices. In this research we present a new direct patterning technique in which laser photoreduction of silver from a liquid is controlled by a scanning atomic force microscope tip. While pursuing the formation of patterns using the plasmonic field enhancement of an electromagnetic wave incident on a metallic Atomic Force Microscope (AFM) tip, our group discovered that contrary to expectations, the tip suppresses, rather than enhances, deposition on the underlying substrate, and this suppression persists in the absence of the tip. Experiments presented …


Formulation And Solution Of Electromagnetic Integral Equations Using Constraint-Based Helmholtz Decompositions, Jin Cheng Jan 2012

Formulation And Solution Of Electromagnetic Integral Equations Using Constraint-Based Helmholtz Decompositions, Jin Cheng

Theses and Dissertations--Electrical and Computer Engineering

This dissertation develops surface integral equations using constraint-based Helmholtz decompositions for electromagnetic modeling. This new approach is applied to the electric field integral equation (EFIE), and it incorporates a Helmholtz decomposition (HD) of the current. For this reason, the new formulation is referred to as the EFIE-hd. The HD of the current is accomplished herein via appropriate surface integral constraints, and leads to a stable linear system. This strategy provides accurate solutions for the electric and magnetic fields at both high and low frequencies, it allows for the use of a locally corrected Nyström (LCN) discretization method for the resulting …


Feedback Control For Electron Beam Lithography, Yugu Yang Jan 2012

Feedback Control For Electron Beam Lithography, Yugu Yang

Theses and Dissertations--Electrical and Computer Engineering

Scanning-electron-beam lithography (SEBL) is the primary technology to generate arbitrary features at the nano-scale. However, pattern placement accuracy still remains poor compared to its resolution due to the open-loop nature of SEBL systems. Vibration, stray electromagnetic fields, deflection distortion and hysteresis, substrate charging, and other factors prevent the electron-beam from reaching its target position and one has no way to determine the actual beam position during patterning with conventional systems. To improve the pattern placement accuracy, spatial-phase-locked electron-beam lithography (SPLEBL) provides feedback control of electron-beam position by monitoring the secondary electron signal from electron-transparent fiducial grids on the substrate. While …