Digital Commons Network^™

Channel Modeling And Resource Allocation In Ofdm Systems, Xiang Gao

LSU Doctoral Dissertations

The increasing demand for high data rate in wireless communication systems gives rise to broadband communication systems. The radio channel is plagued by multipath propagation, which causes frequency-selective fading in broadband signals. Orthogonal Frequency-Division Multiplexing (OFDM) is a modulation scheme specifically designed to facilitate high-speed data transmission over frequency-selective fading channels. The problem of channel modeling in the frequency domain is first investigated for the wideband and ultra wideband wireless channels. The channel is converted into an equivalent discrete channel by uniformly sampling the continuous channel frequency response (CFR), which results in a discrete CFR. A necessary and sufficient condition …

Computer Model Of Hybrid Compensator Of Fast Varying Loads, Veronica Bohorquez

LSU Doctoral Dissertations

A computer model of the hybrid compensator of fast varying loads was developed in this dissertation. The computer model was implemented in MFC Visual C++ compiler version 6.0. The classification of fast varying loads and effects of their operation in distribution systems were described in this dissertation. The power properties of fast varying loads were expressed in terms of the Currents' Physical Components Theory. Therefore, the Currents' Physical Components Theory was applied to systems with non-periodic voltages and currents. The supply current of the fast varying loads was decomposed into the useful and the useless components using an algorithm based …

Simple And Efficient Solutions To The Problems Associated With Acoustic Echo Cancellation, Asif Iqbal Mohammad

Doctoral Dissertations

"This dissertation is a collection of papers that addresses several important problems associated with acoustic/line echo cancellation (AEC/LEC), specifically double-talk and echo-path change detection. A double-talk detector is used to freeze AEC filter's adaptation during periods of near-end speech. This dissertation presents three different novel double-talk detection schemes. Simulations demonstrate the efficiency of the proposed algorithms"--Abstract, page iii.

Comparative Evaluation Of Two Models Of Upqc For Suitable Interface To Enhance Power Quality, Malabika Basu, S. P. Das, Gopal Dubey

Articles

Majority of the dispersed generations from renewable energy sources are connected to the grid through power electronic interface, which introduce additional harmonics in the distribution systems. Research is being carried out to integrate active filtering with specific interface such that a common power quality (PQ) platform could be achieved. For generalized solution, a unified power quality conditioner (UPQC) could be the most comprehensive PQ protecting device for sensitive non-linear loads, which require quality input supply. Also, load current harmonic isolation needs to be ensured for maintaining the quality of the supply current. The present paper describes two control scheme models …

The Smart Helmet, Michael Walsh

Theses

This thesis addresses the design, development and testing of a wireless sensor network for a sports helmet. The objective is to monitor an athlete's physiology and also physical impacts using a sensor network. A detailed literature review is presented addressing currently available appropriate wireless technologies, sensors and their operation, packaging, interconnections and applications. It gives a brief introduction to each sensor used in the smart helmet, accelerometers, temperature sensors, heart rate and blood oxygen sensors, along with a review of possible sensors which could be added at a later stage. The specific sensors and other related components for the helmets …

Using Controller Tuning Formulae To Improve Performance, Aidan O'Dwyer

Conference papers

The proportional integral derivative (PID) controller is the most dominant form of automatic controller in industrial use today. With this device, it is necessary to adjust the controller parameters according to the nature of the process. Thus, for effective control of a HVDC system, for example, specific values need to be chosen for the P, I and D parameters, which will be different for the values required to control, for example, an induction motor drive. This tailoring of controller to process is known as controller tuning. Controller tuning is easily and effectively performed using tuning rules (i.e. formulae for controller …

Automatic Bar Line Segmentation, Mikel Gainza, Dan Barry, Eugene Coyle

Conference papers

A method that segments the audio according to the position of the bar lines is presented. The method detects musical bars that frequently repeat in different parts of a musical piece by using an audio similarity matrix. The position of each bar line is predicted by using prior information about the position of previous bar lines as well as the estimated bar length. The bar line segmentation method does not depend on the presence of percussive instruments to calculate the bar length. In addition, the alignment of the bars allows moderate tempo deviations.

A Brief Introduction To Speech Synthesis And Voice Modification, Alan O'Cinneide, David Dorran, Mikel Gainza

Conference papers

For both engineers and linguists, the computer synthesis of natural speech is an objective that would provide many useful applications to human-computer interaction, including the realm of electro-acoustic music. The purpose of this paper is to introduce the area of speech synthesis by providing an overview of the three main methods of computer speech synthesis; namely concatenative, articulatory and formant syntheses. Some aspects of the current state of the technology are illuminated and the final section will explain the author’s motivation and current research approach to the field of voice modification.

Blind Source Separation And Automatic Transcription Of Music Using Tensor Decompositions, Derry Fitzgerald

Conference papers

Recent advances in the use of tensor decompositions for the analysis of music are described. In particular, the use of such decompositions for sound source separation and the automatic transcription of music are explored.

Serum Proteome Profiling Detects Myelodysplastic Syndromes And Identifies Cxc Chemokine Ligands 4 And 7 As Markers For Advanced Disease, Manuel Aivado, Dimitrios Spentzos, Ulrich Germing, Gil Alterovitz, Xiao-Ying Meng, Franck Grall, Aristoteles A. N. Giagounidis, Giannoula Klement, Ulrich Steidl, Hasan H. Otu, Akos Czibere, Wolf C. Prall, Christof Iking-Konert, Michelle Shayne, Marco F. Ramoni, Norbert Gattermann, Rainer Haas, Constantine S. Mitsiades, Eric T. Fung, Towia A. Libermann

Department of Electrical and Computer Engineering: Faculty Publications

Myelodysplastic syndromes (MDS) are among the most frequent hematologic malignancies. Patients have a short survival and often progress to acute myeloid leukemia. The diagnosis of MDS can be difficult; there is a paucity of molecular markers, and the pathophysiology is largely unknown. Therefore, we conducted a multicenter study investigating whether serum proteome profiling may serve as a noninvasive platform to discover novel molecular markers for MDS. We generated serum proteome profiles from 218 individuals by MS and identified a profile that distinguishes MDS from non-MDS cytopenias in a learning sample set. This profile was validated by testing its ability to …

Implementation Of Static And Semi-Static Versions Of A Bit-Wise Pipelined Dual-Rail Ncl 2s Complement Multiplier, R. Sankar, V. Kadiyala, Ravi Bonam, S. Kumar, S. Mohan, F. Kacani, Waleed K. Al-Assadi, Scott C. Smith

Electrical and Computer Engineering Faculty Research & Creative Works

This paper focuses on implementing a 2s complement 8x8 dual-rail bit-wise pipelined multiplier using the asynchronous NULL Convention Logic (NCL) paradigm. The design utilizes a Wallace tree for partial product summation, and is implemented and simulated in VHDL, the transistor level, and the physical level, using a 1.8V 0.18,um TSMC CMOS process.The multiplier is realized using both static and semi-static Dualversions of the NCL gates; and these two implementations are compared in terms of area, power, and speed.

A Proportional-Integrator Type Adaptive Critic Design-Based Neurocontroller For A Static Compensator In A Multimachine Power System, Salman Mohagheghi, Ganesh K. Venayagamoorthy, Yamille Del Valle, Ronald G. Harley

Electrical and Computer Engineering Faculty Research & Creative Works

A novel nonlinear optimal controller for a static compensator (STATCOM) connected to a power system, using artificial neural networks, is presented in this paper. The action dependent heuristic dynamic programming, a member of the adaptive critic designs family is used for the design of the STATCOM neurocontroller. This neurocontroller provides optimal control based on reinforcement learning and approximate dynamic programming. Using a proportional-integrator approach, the proposed neurocontroller is capable of dealing with actual rather than deviation signals. Simulation results are provided to show that the proposed controller outperforms a conventional PI controller for a STATCOM in a small and large …

Experimental Investigation Of The Esd Sensitivity Of An 8-Bit Microcontroller, Lijun Han, Jayong Koo, David Pommerenke, Daryl G. Beetner, Ross Carlton

Electrical and Computer Engineering Faculty Research & Creative Works

In this paper, the susceptibility of an 8-bit microcontroller to electrostatic discharge (ESD) and electrically fast transients was tested by injecting currents through a capacitive probe into the microcontroller package pins. The reaction of the microcontroller to discharges with different rise times and polarities were investigated by measuring the voltage on the tested pins and by observing the microcontroller's clock output. Susceptibility varied significantly when injecting to one pin compared to another. Interestingly, the clock was more sensitive to currents injected into I/O pins than into pins directly related to the clock (e. g. EXTAL). Further work is underway to …

Entopic Lattice Boltzmann Representations Required To Recover Navier Stokes Flows, Brian Keating, George Vahala, Jeffrey Yepez, Min Soe, Linda L. Vahala

Electrical & Computer Engineering Faculty Publications

There are two disparate formulations of the entropic lattice Boltzmann scheme: one of these theories revolves around the analog of the discrete Boltzmann H function of standard extensive statistical mechanics, while the other revolves around the nonextensive Tsallis entropy. It is shown here that it is the nonenforcement of the pressure tensor moment constraints that lead to extremizations of entropy resulting in Tsallis-like forms. However, with the imposition of the pressure tensor moment constraint, as is fundamentally necessary for the recovery of the Navier-Stokes equations, it is proved that the entropy function must be of the discrete Boltzmann form. Three-dimensional …

Power-Aware Design Methodologies For Fpga-Based Implementation Of Video Processing Systems, Hau Trung Ngo

Electrical & Computer Engineering Theses & Dissertations

The increasing capacity and capabilities of FPGA devices in recent years provide an attractive option for performance-hungry applications in the image and video processing domain. FPGA devices are often used as implementation platforms for image and video processing algorithms for real-time applications due to their programmable structure that can exploit inherent spatial and temporal parallelism. While performance and area remain as two main design criteria, power consumption has become an important design goal especially for mobile devices. Reduction in power consumption can be achieved by reducing the supply voltage, capacitances, clock frequency and switching activities in a circuit. Switching activities …

Wave Propagation On Power Cables With Special Regard To Metallic Screen Design, R. Papazyan, Per Pettersson, David Pommerenke

Electrical and Computer Engineering Faculty Research & Creative Works

The high frequency properties of coaxial power cables are modeled using time- and frequency-domain numerical simulations. This is required due to the complex helical structure of the outer metallic screen. The finite element (FEM) and finite difference time domain methods (FDTD) have been employed to study the effect of screen spiralization. It is established that this screen design causes a dependence of the cable high frequency characteristics on the surrounding medium. Analytical model based on modal analysis of wave propagation in coaxial cables confirms the numerical observations.

Noise-Robust Automatic Speech Recognition Using A Discriminative Echo State Network, Mark D. Skowronski, John G. Harris

Electrical and Computer Engineering Faculty Research & Creative Works

The echo state network (ESN) is a recurrent neural network proposed by Herbert Jaeger with a simplified training routine. Previously, we have demonstrated the noise-robust performance of the predictive ESN classifier in automatic speech recognition experiments in which the network was trained to predict the next frame of speech features. Classification performance was limited because the predictive models lacked discriminability, so we changed the model output to a one-of-many output encodings scheme and trained the model discriminatively. Performance was compared to a hidden Markov model (HMM) in small-vocabulary ASR experiments with additive noise. Accuracy of 50% was achieved by a …

A Precompensation Algorithm For Pwm-Based Digital Audio Amplifiers For Portable Applications, Xiaoxiang Gong, John G. Harris

Electrical and Computer Engineering Faculty Research & Creative Works

A novel precompensation algorithm for a Pulse Width Modulation (PWM)-based digital audio amplifier has been developed for portable applications. The Straight-Line Segment PWM (SLSPWM) algorithm results in both low-power and low-complexity devices. The division-free version of this algorithm modifies the algorithm by removing the division using a polynomial approximation. Both SLSPWM and Division-Free SLSPWM feature 16-bit quality performance with fewer calculations compared with previous works. © 2007 IEEE.

Training Winner-Take-All Simultaneous Recurrent Neural Networks, Xindi Cai, Danil V. Prokhorov, Donald C. Wunsch

Electrical and Computer Engineering Faculty Research & Creative Works

The winner-take-all (WTA) network is useful in database management, very large scale integration (VLSI) design, and digital processing. The synthesis procedure of WTA on single-layer fully connected architecture with sigmoid transfer function is still not fully explored. We discuss the use of simultaneous recurrent networks (SRNs) trained by Kalman filter algorithms for the task of finding the maximum among N numbers. The simulation demonstrates the effectiveness of our training approach under conditions of a shared-weight SRN architecture. A more general SRN also succeeds in solving a real classification application on car engine data.

New Techniques To Improve Power Quality And Evaluate Stability In Modern All-Electric Naval Ship Power Systems, Peng Xiao

Doctoral Dissertations

"This dissertation focuses on two crucial issues in the design and analysis of the power electronic systems on modern all-electric naval ships, i.e., power quality control and stability evaluation. It includes three papers that deal with active power filter topology, active rectifier control, and impedance measurement techniques, respectively. To mitigate harmonic currents generated by high-power high-voltage shipboard loads such as propulsion motor drives, the first paper proposes a novel seven-level shunt active power filter topology, which utilizes tapped reactors for parallel operations of switching devices. The multi-level system has been implemented in both regular digital simulation and real-time digital simulator …

A Software Defined Radio For Research Into Cognitive Radio, Jason Michael Pratt

Masters Theses

Software defined radios are capable of transmitting and receiving signals over a broad range of frequencies, and can alter their carrier frequency, modulation scheme, and power level by changing the software controlling the radio. Because of these capabilities, a software defined radio is the necessary platform for research into cognitive radio. The aim of cognitive radio is to more fully utilize the RF spectrum by allowing wireless communication systems to scan the spectrum for unused frequency bands and dynamically establish communication over one of those unused bands. This thesis gives a brief introduction into cognitive radio, and currently existing software …

Dynamic Voltage Scaling For Priority-Driven Scheduled Distributed Real-Time Systems, Chenxing Wang

University of Kentucky Doctoral Dissertations

Energy consumption is increasingly affecting battery life and cooling for real- time systems. Dynamic Voltage and frequency Scaling (DVS) has been shown to substantially reduce the energy consumption of uniprocessor real-time systems. It is worthwhile to extend the efficient DVS scheduling algorithms to distributed system with dependent tasks. The dissertation describes how to extend several effective uniprocessor DVS schedul- ing algorithms to distributed system with dependent task set. Task assignment and deadline assignment heuristics are proposed and compared with existing heuristics concerning energy-conserving performance. An admission test and a deadline com- putation algorithm are presented in the dissertation for dynamic …

Reactive Oxygen Emission From Microwave Discharge Plasmas, S. Popovic, M. Rašković, S. P. Kuo, L. Vuskovic

Physics Faculty Publications

Metastable oxygen atoms and molecules have received increased interest because of their function in surface modification, bio-decontamination and many other industrial applications, in addition to the role in the upper atmospheric layer chemistry. We review work on production and detection of metastable oxygen and we describe our experiments, including the development of techniques for measurement of metastable molecular oxygen. We show that either metastable oxygen molecules or metastable oxygen atoms can be produced in large quantities in electrical discharges, carefully tailored to promote the required kinetics. Although the two species may coexist, colder discharge regimes favor production of molecules, while …

Multiresolution Wavelet Analysis Of Event-Related Eeg Potentials Using Ensemble Of Classifier Data Fusion Techniques For Early Diagnosis Of Alzheimer's Disease, Apostolos Topalis

Theses and Dissertations

The recent advances and knowledge in medicine and nutrition have greatly improved our average life expectancy. An unfortunate consequence of this longer life span, however, is a dramatic increase in the number of individuals suffering from dementia, and more specifically, from Alzheimer's disease (AD). Furthermore, AD remains under-diagnosed and under-treated until its more severe stages due to lack of standard diagnostic tools available to community clinics. A search for biomarkers that will allow early diagnosis of the disease is therefore necessary to develop effective medical treatments. Such a biomarker should be non-invasive, simple to obtain, safe, inexpensive, accurate, and most …

Random Feature Subspace Ensemble Based Approaches For The Analysis Of Data With Missing Features, Hussein Syed Mohammed

Theses and Dissertations

Missing data in real world applications is not an uncommon occurrence. It is not unusual for training, validation or field data to have missing features in some (or even all) of their instances, as bad sensors, failed pixels, malfunctioning equipment, unexpected noise causing signal saturation, data corruption, and so on, are all familiar scenarios in many practical applications.

In this thesis, the feasibility of an ensemble of classifiers trained on a feature subset space is investigated as an effective and practical solution for the missing feature problem. Two ensemble of classifiers approach motivated by the Random Subspace Method are proposed …

Use Of Principal Component Analysis With Linear Predictive Features In Developing A Blind Snr Estimation System, Matthew James Marbach

Theses and Dissertations

Signal-to-noise ratio is an important concept in electrical communications, as it is a measurable ratio between a given transmitted signal and the inherent background noise of a transmission channel. Currently signal-to-noise ratio testing is primarily performed by using an intrusive method of comparing a corrupted signal to the original signal and giving it a score based on the comparison. However, this technique is inefficient and often impossible for practical use because it requires the original signal for comparison. A speech signal's characteristics and properties could be used to develop a non-intrusive method for determining SNR, or a method that does …

Data Fusion Of Complementary Information From Parietal And Occipital Event Related Potentials For Early Diagnosis Of Alzheimer's Disease, Nicholas Stepenosky

Theses and Dissertations

The number of the elderly population affected by Alzheimer's disease is rapidly rising. The need to find an accurate, inexpensive, and non-intrusive procedure that can be made available to community healthcare providers for the early diagnosis of Alzheimer's disease is becoming an increasingly urgent public health concern. Several recent studies have looked at analyzing electroencephalogram signals through the use of many signal processing techniques. While their methods show great promise, the final outcome of these studies has been largely inconclusive. The inherent difficulty of the problem may be the cause of this outcome, but most likely it is due to …

Boosted Ensemble Algorithm Strategically Trained For The Incremental Learning Of Unbalanced Data, Michael David Muhlbaier

Theses and Dissertations

Many pattern classification problems require a solution that needs to be incrementally updated over a period of time. Incremental learning problems are often complicated by the appearance of new concept classes and unbalanced cardinality in training data. The purpose of this research is to develop an algorithm capable of incrementally learning from severely unbalanced data. This work introduces three novel ensemble based algorithms derived from the incremental learning algorithm, Learn++. Learn++.NC is designed specifically for incrementally learning New Classes through dynamically adjusting the combination weights of the classifiers' decisions. Learn++.UD handles Unbalanced Data through class-conditional voting …

Wavefront Curvature Sensing From Image Projections, Jonathan C. Buffington

Theses and Dissertations

This research outlines the development and simulation of a signal processing approach to real time wavefront curvature sensing in adaptive optics. The signal processing approach combines vectorized Charge Coupled Device (CCD) read out with a wavefront modal estimation technique. The wavefront sensing algorithm analyzes vector projections of image intensity data to provide an estimate of the wavefront phase as a combination of several low order Zernike polynomial modes. This wavefront sensor design expands on an existing idea for vector based tilt sensing by providing the ability to compensate for additional modes. Under the proposed wavefront sensing approach, the physical wavefront …

2006 Fall Engr333 Project Final Report, 2006 Fall Engr333

ENGR 333

The objective of this project was to demonstrate Calvin’s interest in alternative energy. The development of a short-term plan to implement a demonstration wind turbine and a long-term plan to determine the feasibility of a larger turbine for the future demonstrates this interest. The class was divided into five teams: management, external relations, long-term technology, short-term technology, and campus infrastructure. While each team had its own objectives, everyone worked together to share information and accomplish the overall project goals. This management technique provided necessary structure and simulated an environment typically found in a career environment.