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Independent Component Analysis Enhancements For Source Separation In Immersive Audio Environments, Yue Zhao 2013 University of Kentucky

Independent Component Analysis Enhancements For Source Separation In Immersive Audio Environments, Yue Zhao

Theses and Dissertations--Electrical and Computer Engineering

In immersive audio environments with distributed microphones, Independent Component Analysis (ICA) can be applied to uncover signals from a mixture of other signals and noise, such as in a cocktail party recording. ICA algorithms have been developed for instantaneous source mixtures and convolutional source mixtures. While ICA for instantaneous mixtures works when no delays exist between the signals in each mixture, distributed microphone recordings typically result various delays of the signals over the recorded channels. The convolutive ICA algorithm should account for delays; however, it requires many parameters to be set and often has stability issues. This thesis introduces the …


Multi-Mode Self-Referencing Surface Plasmon Resonance Sensors, Jing Guo 2013 University of Kentucky

Multi-Mode Self-Referencing Surface Plasmon Resonance Sensors, Jing Guo

Theses and Dissertations--Electrical and Computer Engineering

Surface-plasmon-resonance (SPR) sensors are widely used in biological, chemical, medical, and environmental sensing. This dissertation describes the design and development of dual-mode, self-referencing SPR sensors supporting two surface-plasmon modes (long- and short-range) which can differentiate surface binding interactions from bulk index changes at a single sensing location. Dual-mode SPR sensors have been optimized for surface limit of detection (LOD). In a wavelength interrogated optical setup, both surface plasmons are simultaneously excited at the same location and incident angle but at different wavelengths. To improve the sensor performance, a new approach to dual-mode SPR sensing is presented that offers improved differentiation …


Target Tracking With Binary Sensor Networks, Mengmei Liu 2013 University of Kentucky

Target Tracking With Binary Sensor Networks, Mengmei Liu

Theses and Dissertations--Electrical and Computer Engineering

Binary Sensor Networks are widely used in target tracking and target parameter estimation. It is more computationally and financially efficient than surveillance camera systems. According to the sensing area, binary sensors are divided into disk shaped sensors and line segmented sensors. Different mathematical methods of target trajectory estimation and characterization are applied. In this thesis, we present a mathematical model of target tracking including parameter estimation (size, intrusion velocity, trajectory, etc.) with line segmented sensor networks. Software simulation and hardware experiments are built based on the model. And we further analyze how the quantization noise affects the results.


Microphone Array Optimization In Immersive Environments, Jingjing Yu 2013 University of Kentucky

Microphone Array Optimization In Immersive Environments, Jingjing Yu

Theses and Dissertations--Electrical and Computer Engineering

The complex relationship between array gain patterns and microphone distributions limits the application of traditional optimization algorithms on irregular arrays, which show enhanced beamforming performance for human speech capture in immersive environments. This work analyzes the relationship between irregular microphone geometries and spatial filtering performance with statistical methods. Novel geometry descriptors are developed to capture the properties of irregular microphone distributions showing their impact on array performance. General guidelines and optimization methods for regular and irregular array design are proposed in immersive (near-field) environments to obtain superior beamforming ability for speech applications. Optimization times are greatly reduced through the objective …


An Attitude Determination System With Mems Gyroscope Drift Compensation For Small Satellites, Maxwell Bezold 2013 University of Kentucky

An Attitude Determination System With Mems Gyroscope Drift Compensation For Small Satellites, Maxwell Bezold

Theses and Dissertations--Electrical and Computer Engineering

This thesis presents the design of an attitude determination system for small satellites that automatically corrects for attitude drift. Existing attitude determination systems suffer from attitude drift due to the integration of noisy rate gyro sensors used to measure the change in attitude. This attitude drift leads to a gradual loss in attitude knowledge, as error between the estimated attitude and the actual attitude increases.

In this thesis a Kalman filter is used to complete sensor fusion which combines sensor observations with a projected attitude based on the dynamics of the satellite. The system proposed in this thesis also utilizes …


Visual Attitude Propagation For Small Satellites, Samir Ahmed Rawashdeh 2013 University of Kentucky

Visual Attitude Propagation For Small Satellites, Samir Ahmed Rawashdeh

Theses and Dissertations--Electrical and Computer Engineering

As electronics become smaller and more capable, it has become possible to conduct meaningful and sophisticated satellite missions in a small form factor. However, the capability of small satellites and the range of possible applications are limited by the capabilities of several technologies, including attitude determination and control systems. This dissertation evaluates the use of image-based visual attitude propagation as a compliment or alternative to other attitude determination technologies that are suitable for miniature satellites. The concept lies in using miniature cameras to track image features across frames and extracting the underlying rotation.

The problem of visual attitude propagation as …


Perceptual Ruler For Quantifying Speech Intelligibility In Cocktail Party Scenarios, Kirstin M. Brangers 2013 University of Kentucky

Perceptual Ruler For Quantifying Speech Intelligibility In Cocktail Party Scenarios, Kirstin M. Brangers

Theses and Dissertations--Electrical and Computer Engineering

Systems designed to enhance intelligibility of speech in noise are difficult to evaluate quantitatively because intelligibility is subjective and often requires feedback from large populations for consistent evaluations. Attempts to quantify the evaluation have included related measures such as the Speech Intelligibility Index. These require separating speech and noise signals, which precludes its use on experimental recordings. This thesis develops a procedure using an Intelligibility Ruler (IR) for efficiently quantifying intelligibility. A calibrated Mean Opinion Score (MOS) method is also implemented in order to compare repeatability over a population of 24 subjective listeners. Results showed that subjects using the IR …


Tunable Fano Resonances Based On Two-Beam Interference In Microring Resonator, Ting Hu, Ping Yu, Chen Qui, Huiye Qui, Fan Wang, Mei Yang, Xiaoqing Jiang, Hui Yu, Jianyi Yang 2013 Zhejiang University of Technology

Tunable Fano Resonances Based On Two-Beam Interference In Microring Resonator, Ting Hu, Ping Yu, Chen Qui, Huiye Qui, Fan Wang, Mei Yang, Xiaoqing Jiang, Hui Yu, Jianyi Yang

Electrical & Computer Engineering Faculty Research

In this paper, a resonant system is demonstrated on silicon-on-insulator wafer to achieve tunable Fano resonances. In this system, the Fano resonance originates from the interference of two beams resonant in the microring resonator. The shapes of the Fano resonances are tunable through controlling the phase difference of the two beams. Both large slope and high extinctionratio (ER) are obtained when the phase difference is 0.5π or 1.5π. Experimental results show that Fano resonances with steep slope and ER over 20 dB are achieved in the whole free spectral range by controlling the microheaters to meet the phase condition.


Estimation Of Performance Indices For The Planning Of Sustainable Transportation Systems, Alexander Paz, Pankaj Maheshwari 2013 University of Nevada, Las Vegas

Estimation Of Performance Indices For The Planning Of Sustainable Transportation Systems, Alexander Paz, Pankaj Maheshwari

Electrical & Computer Engineering Faculty Research

In the context of sustainable transportation systems, previous studies have either focused only on the transportation systemor have not used a methodology that enables the treatment of incomplete, vague, and qualitative information associated with the available data. This study proposes a system of systems (SOS) and a fuzzy logic modeling approach. The SOS includes the Transportation, Activity, and Environment systems. The fuzzy logic modeling approach enables the treatment of the vagueness associated with some of the relevant data. Performance Indices (PIs) are computed for each system using a number of performance measures. The PIs illustrate the aggregated performance of each …


Framework For Simulation Of Heterogeneous Mpsoc For Design Space Exploration, Bisrat Tafesse, Venkatesan Muthukumar 2013 University of Nevada, Las Vegas

Framework For Simulation Of Heterogeneous Mpsoc For Design Space Exploration, Bisrat Tafesse, Venkatesan Muthukumar

Electrical & Computer Engineering Faculty Research

Due to the ever-growing requirements in high performance data computation, multiprocessor systems have been proposed to solve the bottlenecks in uniprocessor systems. Developing efficient multiprocessor systems requires effective exploration of design choices like application scheduling, mapping, and architecture design. Also, fault tolerance in multiprocessors needs to be addressed. With the advent of nanometer-process technology for chip manufacturing, realization of multiprocessors on SoC (MpSoC) is an active field of research. Developing efficient low power, fault-tolerant task scheduling, and mapping techniques for MpSoCs require optimized algorithms that consider the various scenarios inherent in multiprocessor environments. Therefore there exists a need to develop …


Advanced Water Vapor Lidar Detection System, Hani Elsayed-Ali 2013 Old Dominion University

Advanced Water Vapor Lidar Detection System, Hani Elsayed-Ali

Electrical & Computer Engineering Faculty Publications

In the present water vapor lidar system, the detected signal is sent over long cables to a waveform digitizer in a CAMAC crate. This has the disadvantage of transmitting analog signals for a relatively long distance, which is subjected to pickup noise, leading to a decrease in the signal to noise ratio.

Generally, errors in the measurement of water vapor with the DIAL method arise from both random and systematic sources. Systematic errors in DIAL measurements are caused by both atmospheric and instrumentation effects. The selection of the on-line alexandrite laser with a narrow linewidth, suitable intensity and high spectral …


Automated Extraction And Classification Of Time-Frequency Contours In Humpback Vocalizations, Hui Ou, Whitlow W.L. Au, Lisa M. Zurk, Marc O. Lammers 2013 Portland State University

Automated Extraction And Classification Of Time-Frequency Contours In Humpback Vocalizations, Hui Ou, Whitlow W.L. Au, Lisa M. Zurk, Marc O. Lammers

Electrical and Computer Engineering Faculty Publications and Presentations

A time-frequency contour extraction and classification algorithm was created to analyze humpback whale vocalizations. The algorithm automatically extracted contours of whale vocalization units by searching for gray-level discontinuities in the spectrogram images. The unit-to-unit similarity was quantified by cross-correlating the contour lines. A library of distinctive humpback units was then generated by applying an unsupervised, cluster-based learning algorithm. The purpose of this study was to provide a fast and automated feature selection tool to describe the vocal signatures of animal groups. This approach could benefit a variety of applications such as species description, identification, and evolution of song structures. The …


Online Nonintrusive Condition Monitoring And Fault Detection For Wind Turbines, Xiang Gong 2012 University of Nebraska-Lincoln

Online Nonintrusive Condition Monitoring And Fault Detection For Wind Turbines, Xiang Gong

Department of Electrical and Computer Engineering: Dissertations, Theses, and Student Research

The goal of this dissertation research is to develop online nonintrusive condition monitoring and fault detection methods for wind turbine generators (WTGs). The proposed methods use only the current measurements that have already been used by the control and protection systems of WTGs; no additional sensors or data acquisition devices are needed. Current-based condition monitoring and fault detection techniques have great economic benefits and the potential to be adopted by the wind energy industry. However, there are challenges in using current measurements for wind turbine condition monitoring and fault detection. First, it is a challenge to extract WTG fault signatures …


A Nonparametric Approach To Segmentation Of Ladar Images, Eric A. Buschelman 2012 Air Force Institute of Technology

A Nonparametric Approach To Segmentation Of Ladar Images, Eric A. Buschelman

Theses and Dissertations

The advent of advanced laser radar (ladar) systems that record full-waveform signal data has inspired numerous inquisitions which aspire to extract additional, previously unavailable, information about the illuminated scene from the collected data. The quality of the information, however, is often related to the limitations of the ladar camera used to collect the data. This research project uses full-waveform analysis of ladar signals, and basic principles of optics, to propose a new formulation for an accepted signal model. A new waveform model taking into account backscatter reflectance is the key to overcoming specific deficiencies of the ladar camera at hand, …


Modeling The Effects Of The Local Environment On A Received Gnss Signal, Marshall E. Haker 2012 Air Force Institute of Technology

Modeling The Effects Of The Local Environment On A Received Gnss Signal, Marshall E. Haker

Theses and Dissertations

There is an ongoing need in the GNSS community for the development of high-fidelity simulators which generate data that replicates what can truly be expected from a challenging environment such as an urban canyon or an indoor environment. The algorithm developed for use in the research in this dissertation, the Signal Decomposition and Parameterization Algorithm (SDPA), is presented in order to respond to this need. This algorithm is designed to decompose a signal received using a GNSS recording and playback system and output parameters that can be used to reconstruct the effects on the signal of the environment local to …


Early Forest Fire Detection Using Texture, Blob Threshold, And Motion Analysis Of Principal Components, Georges Fouad Moussa 2012 California Polytechnic State University, San Luis Obispo

Early Forest Fire Detection Using Texture, Blob Threshold, And Motion Analysis Of Principal Components, Georges Fouad Moussa

Master's Theses

Forest fires constantly threaten ecological systems, infrastructure and human lives. The purpose behind this study is minimizing the devastating damage caused by forest fires. Since it is impossible to completely avoid their occurrences, it is essential to accomplish a fast and appropriate intervention to minimize their destructive consequences. The most traditional method for detecting forest fires is human based surveillance through lookout towers. However, this study presents a more modern technique. It utilizes land-based real-time multispectral video processing to identify and determine the possibility of fire occurring within the camera’s field of view. The temporal, spectral, and spatial signatures of …


Noise Reduction With Microphone Arrays For Speaker Identification, Zachary Gideon Cohen 2012 California Polytechnic State University, San Luis Obispo

Noise Reduction With Microphone Arrays For Speaker Identification, Zachary Gideon Cohen

Master's Theses

The presence of acoustic noise in audio recordings is an ongoing issue that plagues many applications. This ambient background noise is difficult to reduce due to its unpredictable nature. Many single channel noise reduction techniques exist but are limited in that they may distort the desired speech signal due to overlapping spectral content of the speech and noise. It is therefore of interest to investigate the use of multichannel noise reduction algorithms to further attenuate noise while attempting to preserve the speech signal of interest.

Specifically, this thesis looks to investigate the use of microphone arrays in conjunction with multichannel …


Passive Ranging Using A Dispersive Spectrometer And Optical Filters, Jacob A. Martin 2012 Air Force Institute of Technology

Passive Ranging Using A Dispersive Spectrometer And Optical Filters, Jacob A. Martin

Theses and Dissertations

Monocular passive ranging using atmospheric oxygen absorption has been demonstrated in the past using an FTS. These instruments are very sensitive to vibration making them di cult to use on an airborne platform. This work focuses on whether passive ranging can be done with instruments that are easier to deploy. Two potential instruments are tested and compared: a diffraction grating spectrometer and optical filters. A grating spectrometer was able to estimate range to within 5% for a static solid rocket motor ring at a distance of 910 m using the NIR absorption band of oxygen. Testing at shorter ranges produced …


Development And Implementation Of A Calibration Procedure For Complex Impedance Spectrum Measurements With Applications To Embedded Battery Health Monitoring And Management Systems, William H. Morrison 2012 University of Connecticut - Storrs

Development And Implementation Of A Calibration Procedure For Complex Impedance Spectrum Measurements With Applications To Embedded Battery Health Monitoring And Management Systems, William H. Morrison

Master's Theses

Energy storage devices such as rechargeable Lithium ion batteries are assuming an increasingly prominent role in society, covering applications from electric / hybrid electric vehicles to personal portable electronics. In response to this increasing demand, technologies that monitor battery health and remaining useful life have developed. One such system is the Smart Battery Status Monitor (SBSM), developed by the Idaho National Laboratory, Montana Tech and Qualtech Systems, Inc. The SBSM utilizes impedance spectrum measurements using a subsystem called the Impedance Measurement Box (IMB). The impedance measurements are complex quantities (having both a resistive and a reactive component) and are made …


Resolution Study Of A Hyperspectral Sensor Using Computed Tomography In The Process Of Noise, Samuel V. Mantravadi 2012 Air Force Institute of Technology

Resolution Study Of A Hyperspectral Sensor Using Computed Tomography In The Process Of Noise, Samuel V. Mantravadi

Theses and Dissertations

Recently, a new type of hyperspectral imaging sensor has been proposed which simultaneously records both spectral data and multiple spatial dimensions. Unlike dispersive imaging spectrometers, chromo-tomographic hyperspectral imaging sensors (CTHIS) record two spatial dimensions as well as a spectral dimension using computed tomography (CT) techniques with only a finite number of spatially-spectrally diverse images. To date, the factors affecting resolution of these sensors have not been examined. This research examines factors affecting resolution, specifically the number of the focus planes needed to resolve a particular object calculated from a theoretical lower bound, determine a method of reconstructing a hyperspectral object …


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