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Photo-Thermal Processing Of Semiconductor Fibers And Thin Films, Nishant Gupta Dec 2012

Photo-Thermal Processing Of Semiconductor Fibers And Thin Films, Nishant Gupta

All Dissertations

Furnace processing and rapid thermal processing (RTP) have been an integral part of several processing steps in semiconductor manufacturing. The performance of RTP techniques can be improved many times by exploiting quantum photo-effects of UV and vacuum ultraviolet (VUV) photons in thermal processing and this technique is known as rapid photo-thermal processing (RPP). As compared to furnace processing and RTP, RPP provides higher diffusion coefficient, lower stress and lower microscopic defects. In this work, a custom designed automated photo assisted processing system was built from individual parts and an incoherent light source. This photo-assisted processing system is used to anneal …


Network Traffic Analysis Using Stochastic Grammars, Chen Lu Dec 2012

Network Traffic Analysis Using Stochastic Grammars, Chen Lu

All Dissertations

Network traffic analysis is widely used to infer information from Internet
traffic. This is possible even if the traffic is encrypted. Previous work uses
traffic characteristics, such as port numbers, packet sizes, and frequency,
without looking for more subtle patterns in the network traffic. In this work,
we use stochastic grammars, hidden Markov models (HMMs) and probabilistic
context-free grammars (PCFGs), as pattern recognition tools for traffic
analysis.
HMMs are widely used for pattern recognition and detection. We use a HMM
inference approach. With inferred HMMs, we use confidence intervals (CI) to
detect if a data sequence matches the HMM. To …


Improving Accuracy In Ultra-Wideband Indoor Position Tracking Through Noise Modeling And Augmentation, Salil Banerjee Dec 2012

Improving Accuracy In Ultra-Wideband Indoor Position Tracking Through Noise Modeling And Augmentation, Salil Banerjee

All Dissertations

The goal of this research is to improve the precision in tracking of an ultra-wideband (UWB) based Local Positioning System (LPS). This work is motivated by the approach taken to improve the accuracies in the Global Positioning System (GPS), through noise modeling and augmentation. Since UWB indoor position tracking is accomplished using methods similar to that of the GPS, the same two general approaches can be used to improve accuracy.
Trilateration calculations are affected by errors in distance measurements from the set of fixed points to the object of interest. When these errors are systemic, each distinct set of fixed …


Investigation Of Auxiliary Winding Harmonic Resonance Phenomena In Single Phase Induction Motors, Gaurav Singh Dec 2012

Investigation Of Auxiliary Winding Harmonic Resonance Phenomena In Single Phase Induction Motors, Gaurav Singh

All Theses

In recent years, the proliferation of single phase power electronics based loads has given rise to a number of power quality issues in the power grid. Harmonics in voltage and current waveforms are one of the biggest problems in this family of power quality issues. Until some years back, power system utilities did not consider harmonics due to small single phase loads to be a big problem. In fact, only large loads were considered as potential hotspots for power quality problems. However, the advent of compact fluorescent lamps (CFLs), personal computers and consumer electronic devices, which utilize rectifier front ends, …


Stochastic Tools For Network Security: Anonymity Protocol Analysis And Network Intrusion Detection, Lu Yu Dec 2012

Stochastic Tools For Network Security: Anonymity Protocol Analysis And Network Intrusion Detection, Lu Yu

All Dissertations

With the rapid development of Internet and the sharp increase of network crime, network security has become very important and received a lot of attention.
In this dissertation, we model security issues as stochastic systems. This allows us to find weaknesses in existing security systems and propose new solutions. Exploring the vulnerabilities of existing security tools can prevent cyber-attacks from taking advantages of the system weaknesses. We consider The Onion Router (Tor), which is one of the most popular anonymity systems in use today, and show how to detect a protocol tunnelled through Tor. A hidden Markov model (HMM) is …


On-Line Transient Stability Studies Incorporating Wind Power, Zhenhua Wang Dec 2012

On-Line Transient Stability Studies Incorporating Wind Power, Zhenhua Wang

All Dissertations

Transient stability is a major concern in power system security and reliability because it is the most common type of instability and its impacts can cause greatest economic losses. For enhancing the energy security, it requires the power system operation to be evaluated during both the planning and the operation stage. Many online/offline transient stability assessment techniques have already been developed for this purpose. However, due to the increase in energy demand, the modern power system has grown to a very sophisticated and large system for which extent transient stability assessment methods may not be able to handle. In addition, …


Performance Evaluation Of Video Streaming In An Infrastructure Mesh Based Vehicle Network, Sajindra Pradhananga Dec 2012

Performance Evaluation Of Video Streaming In An Infrastructure Mesh Based Vehicle Network, Sajindra Pradhananga

All Theses

Most next-generation wireless networks are expected to support video stream-
ing which constitutes the bulk of traffic on the Internet. This thesis evaluates the
performance of video streaming in a vehicle network with an infrastructure wireless
mesh network (WMN) backhaul. Several studies have investigated video quality per-
formance primarily in single hop wireless networks and static WMNs. This thesis is
based on those studies and conducts the study in relation to a network where the
multi-hop features of the mesh network and mobility of the streaming clients may
have substantial impact on the perceived video quality in the network.
The …


Impedance-Based Fault Location Methods For Transmission Line Connecting Wind Farm Plants, Chaoqi Ji Dec 2012

Impedance-Based Fault Location Methods For Transmission Line Connecting Wind Farm Plants, Chaoqi Ji

All Theses

With an increasing capacity of wind power installed in the world, the impact of wind generation during fault condition has been studied. Wind plants equipped with induction generator results in a different fault behavior in transmission networks. In this paper, the validation of existing impedance-based fault location methods are performed on a transmission line connecting wind plant equipped with three different types of induction generators. This work is based on the simulation in real-time digital simulator (RTDS).
Squirrel-cage induction generator (SCIG), wound-rotor induction generator (WRIG) and doubly-fed induction generator (DFIG) are the three common generators used for wind power plants. …


Optimal Energy Management For Microgrids, Zheng Zhao Aug 2012

Optimal Energy Management For Microgrids, Zheng Zhao

All Dissertations

Microgrid is a recent novel concept in part of the development of smart grid. A microgrid is a low voltage and small scale network containing both distributed energy resources (DERs) and load demands. Clean energy is encouraged to be used in a microgrid for economic and sustainable reasons. A microgrid can have two operational modes, the stand-alone mode and grid-connected mode. In this research, a day-ahead optimal energy management for a microgrid under both operational modes is studied. The objective of the optimization model is to minimize fuel cost, improve energy utilization efficiency and reduce gas emissions by scheduling generations …


Fault Analysis Of An Unbalanced Distribution System With Distributed Generation, Parimal Saraf Aug 2012

Fault Analysis Of An Unbalanced Distribution System With Distributed Generation, Parimal Saraf

All Theses

In recent years there has been a lot of emphasis on renewable power integration due to environmental issues and to lower the dependence on fossil fuels. The presence of renewable sources in the distribution systems adds complexity to the calculation of the power flows and hence has a direct impact on the short circuit calculations, protection and control. The presence of unbalance in distribution systems worsens the situation since the three phase voltages and currents are no longer equal in magnitude and 120 degrees phase shifted.
This thesis involves a fault study in a 14-bus distribution system with integrated wind …


Further Investigation On Magnetically Induced Subsequent Fault And Study On Electromagnetic Scattering Of Objects Buried Below A Random Rough Surface, Haiyan Yang May 2012

Further Investigation On Magnetically Induced Subsequent Fault And Study On Electromagnetic Scattering Of Objects Buried Below A Random Rough Surface, Haiyan Yang

All Dissertations

This dissertation contains two subjects: further development of numerical
technique for the analysis of magnetically induced subsequent fault (MISFault) in overhead power lines and its implementation into a software upgrade; and first-phase of study on the electromagnetic scattering from objects buried below a random rough surface making use of the multidomain pseudospectral time domain (PSTD) method and Monte-Carlo simulation. An initial electric fault can result in strong magnetic torque on the overhead power line conductors, which will make them swing and may bring them to close proximity or in contact with one another, causing a subsequent fault. In Chapter 2, …


New Algorithms For High-Throughput Decoding With Low-Density Parity-Check Codes Using Fixed-Point Simd Processors, Jawone Kennedy May 2012

New Algorithms For High-Throughput Decoding With Low-Density Parity-Check Codes Using Fixed-Point Simd Processors, Jawone Kennedy

All Dissertations

Most digital signal processors contain one or more functional units with a single-instruction, multiple-data architecture that supports saturating fixed-point arithmetic with two or more options for the arithmetic precision. The processors designed for the highest performance contain many such functional units connected through an on-chip network. The selection of the arithmetic precision provides a trade-off between the task-level throughput and the quality of the output of many signal-processing algorithms, and utilization of the interconnection network during execution of the algorithm introduces a latency that can also limit the algorithm's throughput.
In this dissertation, we consider the turbo-decoding message-passing algorithm for …


A Person Following Algorithm For Use With A Single Forward Facing Rgb-D Camera On A Mobile Robot, Sean Ficht May 2012

A Person Following Algorithm For Use With A Single Forward Facing Rgb-D Camera On A Mobile Robot, Sean Ficht

All Theses

This thesis examines the problem of person following. A person following algorithm can be separated into two distinct parts: the detection and tracking of a target and the actual following of a target. This thesis focuses mainly on the detection and tracking of a target person. For the purposes of this thesis a simple robot control architecture is used. The robot moves to follow the target in a straight line. No path planning is considered when executing robot movement.
This thesis aims to accomplish three tasks. First, the system should be able to track and follow a target when no …


Glottal Excitation Extraction Of Voiced Speech - Jointly Parametric And Nonparametric Approaches, Yiqiao Chen May 2012

Glottal Excitation Extraction Of Voiced Speech - Jointly Parametric And Nonparametric Approaches, Yiqiao Chen

All Dissertations

The goal of this dissertation is to develop methods to recover glottal flow pulses, which contain biometrical information about the speaker. The excitation information estimated from an observed speech utterance is modeled as the source of an inverse problem.
Windowed linear prediction analysis and inverse filtering are first used to deconvolve the speech signal to obtain a rough estimate of glottal flow pulses. Linear prediction and its inverse filtering can largely eliminate the vocal-tract response which is usually modeled as infinite impulse response filter. Some remaining vocal-tract components that reside in the estimate after inverse filtering are next removed by …


A Study Of Environment Noise In Ultra-Wideband Indoor Position Tracking, William Suski May 2012

A Study Of Environment Noise In Ultra-Wideband Indoor Position Tracking, William Suski

All Dissertations

This work is motivated by the problem of improving the accuracy of indoor ultra-wideband (UWB) position tracking through the study of the environment noise that affects such a system. Current systems can provide accuracy in the range of 30-100 cm in a small building, suitable for applications that require rough room-level precision such as asset tracking and surveillance. Our long-term goal is to improve the accuracy to 1 cm or better, expanding potential applications to telepresence, augmented reality, training and entertainment.
This work investigates the possibility of systematically observing the measurement noise of an UWB position tracking system and building …


Modelling And Characterization Of Magnetic Microfibers, Harshwardhan Karve May 2012

Modelling And Characterization Of Magnetic Microfibers, Harshwardhan Karve

All Theses

Polymer fibers of varying microfluidic properties can be fabricated in a lab setting. Fibers coated with paramagnetic particles act like slender paramagnetic beams. These fiber moves in a magnetic field. Thus polymer fibers coated with paramagnetic particles can be used as actuators in various microfluidic applications, such as DNA separation, droplet manipulation and liquid transport. In order to use the fibers as actuators, it is necessary to model the fiber and develop control strategies.
A static model of the paramagnetic fiber based on energy methods is presented in [1]. The model relies on a demagnetizing factors approximation to determine the …