Digital Commons Network^™

Analysis Of Financial Data Using Non-Negative Matrix Factorization, Ruairí De Fréin, Konstantinos Drakakis, Scott Rickard, Andrzej Cichocki

Articles

We apply Non-negative Matrix Factorization (NMF) to the prob-lem of identifying underlying trends in stock market data. NMF is arecent and very successful tool for data analysis including image andaudio processing; we use it here to decompose a mixture a data, thedaily closing prices of the 30 stocks which make up the Dow Jones In-dustrial Average, into its constitute parts, the underlying trends which govern the financial marketplace. We demonstrate how to impose ap-propriate sparsity and smoothness constraints on the components of thedecomposition. Also, we describe how the method clusters stocks to-gether in performance-based groupings which can be used for …

Elliptic Curve Cryptography Security On Restricted Mobile Devices, Debbie Mccann

Theses

Mobile technologies with limited resources, such as smart phones or PDAs, have increased dramatically in popularity. However, the level of security provided for these technologies has not kept pace with the value of the data that they contain or transmit.

Wireless networks usually provide some security, in the form of encryption. GSM and GPRS use different forms of the A5 algorithm, and Wi-Fi uses WEP or WPA. These encryption algorithms have proven weaknesses and in some cases have been efficiently cracked. To improve the security of wireless networks, stronger encryption algorithms need to be developed. One of the most attractive …

Fast And Simple High Resolution Optical Spectrum Analyser, Kai-Uwe Lauterback, Thomas Schneider, Ronny Henker, Max Ammann, Andreas Schwarzbacher

Conference papers

A simple method for fast optical spectroscopy with high resolution is shown. The method is based on the narrowband Brillouin gain process in optical fibers.

Portfolio Diversification Using Subspace Factorizations, Ruairí De Fréin, Konstantinos Drakakis, Scott Rickard

Conference papers

Successful investment management relies on allocating assets so as to beat the stock market. Asset classes are affected by different market dynamics or latent trends. These interactions are crucial to the successful allocation of monies. The seminal work on portfolio management by Markowitz prompts the adroit investment manager to consider the correlation between the assets in his portfolio and to vary his selection so as to optimize his riskreturn profile. The factor model, a popular model for the return generating process has been used for portfolio construction and assumes that there is a low rank representation of the stocks. In …

The Research And Implementation Of Maintenance Excellence On Clean Utility Systems In The Pharmaceutical Indusry, Padraig Liggan

Dissertations

Maintenance Excellence is the implementation of best maintenance practices within industry; it is the balance of performance, risk, and cost to achieve an optimal solution. This thesis has been structured around the 5 main areas of maintenance excellence; it has documented all the important functions of the maintenance department that contributes towards maintenance excellence. Demonstrating maintenance excellence is a big achievement however demonstrating it on pharmaceutical clean utility systems with strict regulatory controls is a major challenge. Pharmaceutical production is one of the most heavily regulated industries. With such an emphasis on product quality in the pharmaceutical industry, and with …

Linear Prediction: The Problem, Its Solution And Application To Speech, Alan O'Cinneide, David Dorran, Mikel Gainza

Conference papers

Linear prediction is a signal processing technique that is used extensively in the analysis of speech signals and, as it is so heavily referred to in speech processing literature, a certain level of familiarity with the topic is typically required by all speech processing engineers. This paper aims to provide a well-rounded introduction to linear prediction, and so doing, facilitate the understanding of the technique. Linear prediction and its mathematical derivation will be described, with a specific focus on applying the technique to speech signals. It is noted, however, that although progress in linear prediction has been driven primarily by …

Reliability-Based Stand-Alone Photovoltaic System Sizing Design- A Case Study, Haifeng Ge, Liqin Ni, Sohrab Asgarpoor

Department of Electrical and Computer Engineering: Faculty Publications

This paper introduces a method for designing a standalone photovoltaic system to improve the load point reliability, extend the operation life, and minimize the design cost. This approach examines the impacts of solar panel sizes, tilt angles and battery volumes toward load point reliability, as well as the expected system life, by using real insolation data in a given location and random load burdens. The reliability evaluation incorporating solar insolation variations and load point uncertainty is performed. Life evaluation of battery is included in this paper with consideration of the battery State of Charge (SoC) history. The Economical analysis to …

A Quantitative Study Of Mobility Impact For Real- Time Services On A Wi-Fi Multi-Hop Network, Ting Zhou, Hamid Sharif, Michael Hempel, Puttipong Mahasukhon, Wei Wang, Song Ci

Department of Electrical and Computer Engineering: Faculty Publications

In this paper, we analyze the performance of mobile real time services in a large-scale IEEE 802.11 multi-hop network. We present our field measurements with discussion of performance bottlenecks for VoIP services under mobile scenarios. We utilized our test bed which is located in Nebraska and supported by the University of Nebraska-Lincoln (UNL), US Federal Railroads Administrations (FRA), and major US railroad companies. Our UNL-FRA test bed consists of 8 outdoor access point towers, which are deployed along 3.5 mile of BNSF railroad. Passive measurement approaches are taken to ensure the integrity of collected data and multi-layer stream based packet …

Gene Expression Analysis Of Embryonic Stem Cells Expressing Ve-Cadherin (Cd144) During Endothelial Differentiation, Vesna Nikolova-Krstevski, Manoj Bhasin, Hasan H. Otu, Towia A. Libermann, Peter Oettgen

Department of Electrical and Computer Engineering: Faculty Publications

Background: Endothelial differentiation occurs during normal vascular development in the developing embryo. This process is recapitulated in the adult when endothelial progenitor cells are generated in the bone marrow and can contribute to vascular repair or angiogenesis at sites of vascular injury or ischemia. The molecular mechanisms of endothelial differentiation remain incompletely understood. Novel approaches are needed to identify the factors that regulate endothelial differentiation.

Methods: Mouse embryonic stem (ES) cells were used to further define the molecular mechanisms of endothelial differentiation. By flow cytometry a population of VEGF-R2 positive cells was identified as early as 2.5 days after differentiation …

Ex-Situ And In-Situ Selenization Of Copper-Indium And Copper-Boron Thin Films, Rodney J. Soukup, Natale J. Ianno, Chad Kamler, Martin Diaz, Shuchi Sharma, James Huguenin-Love, Jiri Olejnicek

Department of Electrical and Computer Engineering: Faculty Publications

It has recently been established that the ideal bandgap for terrestrial photovoltaics is 1.37 eV and the bandgap for CulnSe2 is only around 1.04 eV. Thus, a larger bandgap is needed. However, neither the substitution of Ga nor of AI has made a high efficiency solar cell absorber with a band gap of 1.37 eV possible. B, an even smaller atom, should require less atomic substitution than either Ga or AI to achieve a wider bandgap. In order to fabricate a thin film of Culn_xB_1-xSe₂ (CIBS), Cu, In and B were deposited from a variety …

Modeling And Analysis Of Split And Merge Production Systems, Yang Liu

University of Kentucky Master's Theses

Many production systems have split and merge operations to increase production capac- ity and variety, improve product quality, and implement product control and scheduling policies. This thesis presents analytical methods to model and analyze split and merge production systems with Bernoulli and exponential reliability machines under circulate, priority and percentage policies. The recursive procedures for performance analysis are de- rived, and the convergence of the procedures and uniqueness of the solutions, along with the structural properties, are proved analytically, and the accuracy of the estimation is justi¯ed numerically with high precision. In addition, comparisons among the e®ects of di®erent policies …

Efficient Mrf Approach To Document Image Enhancement, Tayo Obafemi-Ajayi, Gady Agam, Ophir Frieder

Electrical and Computer Engineering Faculty Research & Creative Works

Markov random field (MRF) based approaches have been shown to perform well in a wide range of applications. Due to the iterative nature of the algorithm, the computational cost of such applications is normally high. In the context of document image analysis, where numerous documents have to be processed, this computational cost may become prohibitive. We describe a novel approach to document image enhancement using MRF. We show that by using domain specific knowledge, we are able to substantially improve computational performance by an order of magnitude. Moreover, in contrast to known techniques where patch initialization is arbitrary, in the …

Fit Numerical Modeling For Emi Discovery And "Design", James L. Drewniak

Electrical and Computer Engineering Faculty Research & Creative Works

No abstract provided.

Prediction Of Breathing Patterns Using Neural Networks, Pavani Davuluri

Theses and Dissertations

During the radio therapy treatment, it has been difficult to synchronize the radiation beam with the tumor position. Many compensation techniques have been used before. But all these techniques have some system latency, up to a few hundred milliseconds. Hence it is necessary to predict tumor position to compensate for the control system latency. In recent years, many attempts have been made to predict the position of a moving tumor during respiration. Analyzing external breathing signals presents a methodology in predicting the tumor position. Breathing patterns vary from very regular to irregular patterns. The irregular breathing patterns make prediction difficult. …

Homography Based Multiple Camera Detection Of Camouflaged Targets, Jesus Flores Guerra

Open Access Theses & Dissertations

This Thesis proposes an improvement on segmentation of camouflaged objects by combining information from multiple static cameras with overlapping views onto a common reference plane. Previous camouflage detection work relies on a single camera and focuses on pattern recognition, gray level co-occurrence matrix (GLCM) computation, convexity detection and operations such as connected components or morphology. These methods make real-time implementation computationally expensive. The proposed work diverges from these techniques, taking advantage of the added information from several viewpoints. Background subtraction is performed on each individual camera and then, the segmentation result is transformed onto a common plane using homography. A …

Assessment Of Human Muscle Fatigue From Surface Emg Signals Recorded During Isometric Voluntary Contractions By Using A Cosine Modulated Filter Bank, Cristhian Mauricio Potes

Open Access Theses & Dissertations

Human muscle fatigue involves both a decrease in the frequency and increase in the amplitude of a surface electromyographic (EMG) signal. Muscle fatigue is also related to a decrease of the force impeding to reach the same initial level of the maximum voluntary contraction (MVC). To determine muscle fatigue indices, a method is proposed by decomposing a surface EMG signal into 32-subbands. This decomposition was attained by using a cosine modulated filter bank. The

surface EMG signals analyzed during this research were recorded during isometric voluntary contractions. Both the instantaneous mean frequency (IMF) and the instantaneous amplitude (IA) are estimated …

Quiescent Current Testing Of Cmos Data Converters, Siva Yellampalli

LSU Doctoral Dissertations

Power supply quiescent current (IDDQ) testing has been very effective in VLSI circuits designed in CMOS processes detecting physical defects such as open and shorts and bridging defects. However, in sub-micron VLSI circuits, IDDQ is masked by the increased subthreshold (leakage) current of MOSFETs affecting the efficiency of I¬DDQ testing. In this work, an attempt has been made to perform robust IDDQ testing in presence of increased leakage current by suitably modifying some of the test methods normally used in industry. Digital CMOS integrated circuits have been tested successfully using IDDQ and IDDQ methods for physical defects. However, testing of …

Overview Of Biocreative Ii Gene Mention Recognition, Larry Smith, Lorraine K. Tanabe, Rie Johnson Nee Ando, Cheng-Ju Kuo, I-Fang Chung, Chun-Nan Hsu, Yu-Shi Lin, Roman Klinger, Christoph M. Friedrich, Kuzman Ganchev, Manabu Torii, Hongfang Liu, Barry Haddow, Craig A. Struble, Richard J. Povinelli, Andreas Vlachos, William A. Baumgartner, Lawrence Hunter, Bob Carpenter, Richard Tzong-Han Tsai, Hong-Jie Dai, Feng Liu, Yifei Chen, Chengjie Sun, Sophia Katrenko, Pieter Adriaans, Christian Blaschke, Rafael Torres, Mariana Neves, Preslav Nakov, Anna Divoli, Manuel Maña-López, Jacinto Mata, W John Wilbur

Electrical and Computer Engineering Faculty Research and Publications

Nineteen teams presented results for the Gene Mention Task at the BioCreative II Workshop. In this task participants designed systems to identify substrings in sentences corresponding to gene name mentions. A variety of different methods were used and the results varied with a highest achieved F₁ score of 0.8721. Here we present brief descriptions of all the methods used and a statistical analysis of the results. We also demonstrate that, by combining the results from all submissions, an F score of 0.9066 is feasible, and furthermore that the best result makes use of the lowest scoring submissions.

A Capacity-Approaching Coded Modulation Scheme For Non-Coherent Fading Channels, Youngjeon Cho

LSU Master's Theses

Approaching the Shannon limit of the communication channels has been studied by many researchers to efficiently and reliably transmit data through the channels. To solve this problem, various methods and schemes have been proposed for approaching the theoretical limit for Shannon’s channel capacity. Among them, both low-density parity check (LDPC) codes and Turbo codes have been proposed to minimize the bit error rate (BER). Therefore, understanding of LDPC codes and Turbo codes is useful for their applications in modern communication systems. The study about non-coherent channels, which do not require explicit knowledge or estimation of the channel state information, has …

Enhancing Security In Quantum Cryptography, Partha Basuchowdhuri

LSU Master's Theses

Quantum Key Distribution was named as one of the top ten emerging technologies by Technology Review Journal in 2003 in their annual edition. The growth in quantum cryptography since the beginning of the millennium has been expedited by new theories and ideas. The introduction of practical quantum cryptosystems offered by USA based company MagiQTech and its European rival idQuantique has changed the face of cryptography. With active experimental research in USA, Europe, Japan and Singapore, the scope of quantum cryptography seems to be growing daily. When Bennett and Brassard proposed their BB84 protocol in Bangalore in 1984, no one would …

Development Of An Algorithm For Switching Compensator Control Based On The Currents' Physical Components Theory, Samuel Pearce

LSU Master's Theses

Development of a three-phase switching compensator algorithm, based on the Currents’ Physical Components (CPC) power theory and capable of performing in real time, is the subject of this thesis. The compensator algorithm could be implemented to control a PWM Inverter, which would perform as a shunt switching compensator of harmonic, reactive and unbalanced currents or a customizable combination of the three. The hardware used to demonstrate the ability of the algorithm to perform within the restraints or real time operation is a Motorola DSP56F807 evaluation mode DSP board and a set of voltage and current sensors. The Evaluation Board was …

Vegetation Identification Based On Satellite Imagery, Vamsi K.R. Mantena, Ramu Pedada, Srinivas Jakkula, Yuzhong Shen, Jiang Li, Hamid R. Arabnia (Ed.)

Electrical & Computer Engineering Faculty Publications

Automatic vegetation identification plays an important role in many applications including remote sensing and high performance flight simulations. This paper presents a method to automatically identify vegetation based upon satellite imagery. First, we utilize the ISODATA algorithm to cluster pixels in the images where the number of clusters is determined by the algorithm. We then apply morphological operations to the clustered images to smooth the boundaries between clusters and to fill holes inside clusters. After that, we compute six features for each cluster. These six features then go through a feature selection algorithm and three of them are determined to …

Activation Energy Of Surface Diffusion And Terrace Width Dynamics During The Growth Of In (4×3) On Si (100) - (2×1) By Femtosecond Pulsed Laser Deposition, M. A. Hafez, H. E. Elsayed-Ali

Electrical & Computer Engineering Faculty Publications

The nucleation and growth of indium on a vicinal Si (100) - (2×1) surface at high temperature by femtosecond pulsed laser deposition was investigated by in situ reflection high energy electron diffraction (RHEED). RHEED intensity relaxation was observed for the first ∼2 ML during the growth of In (4×3) by step flow. From the temperature dependence of the rate of relaxation, an activation energy of 1.4±0.2 eV of surface diffusion was determined. The results indicate that indium small clusters diffused to terrace step edges with a diffusion frequency constant of (1.0±0.1) × 10¹¹ s^-1. The RHEED specular …

Towards A Metric For The Assessment Of Safety Critical Control Systems, Oscar R. Gonzalez, Jorge R. Chavez-Fuentes, W. Steven Gray

Electrical & Computer Engineering Faculty Publications

There is a need for better integration of the fault tolerant and the control designs for safety critical systems such as aircraft. The dependability of current designs is assessed primarily with measures of the interconnection of fault tolerant components: the reliability function and the mean time to failure. These measures do not directly take into account the interaction of the fault tolerant components with the dynamics of the aircraft. In this paper, a first step to better integrate these designs is made. It is based on the observation that unstable systems are intrinsically unreliable and that a necessary condition for …

Can Laser Speckle Flowmetry Be Made A Quantitative Tool?, Donald D. Duncan, Sean J. Kirkpatrick

Electrical and Computer Engineering Faculty Publications and Presentations

The ultimate objective of laser speckle flowmetry (and a host of specific implementations such as laser speckle contrast analysis, LASCA or LSCA; laser speckle spatial contrast analysis, LSSCA; laser speckle temporal contrast analysis, LSTCA; etc.) is to infer flow velocity from the observed speckle contrast. Despite numerous demonstrations over the past 25 years of such a qualitative relationship, no convincing quantitative relationship has been proven. One reason is a persistent mathematical error that has been propagated by a host of workers; another is a misconception about the proper autocorrelation function for ordered flow. Still another hindrance has been uncertainty in …

Optimization Of Optical Computed Tomography Techniques For The Synthesis Of Particle Aggregate Models, Patrick Anthony Giordano Jr.

Theses and Dissertations

The characterization of 3-D shapes of particles in geomaterial aggregate mixtures is important for understanding the micro-mechanics of granular materials. Also, numerical synthesis of 3-D particle shapes from their corresponding shape descriptors is required for developing discrete element models (DEMs) that can be used to predict particle contact-forces, and ultimately the shear strength of the aggregate mixture.

Previous work has shown that Fourier-based 3-D shape descriptors can be constructed for aggregate mixtures, using a statistical combination of 2-D projections. Furthermore, optical tomography methods using the Algebraic Reconstruction Technique (ART) algorithm has proved capable of synthesizing 3-D shapes from 2-D projections, …

Development Of The Impedance-Based Arc-Flash Determination Device (Iadd), Timothy Smith

All Theses

This thesis entitled, 'Development of the Impedance based Arc-Fault Determination Device (IADD)' details the development of a testing device that, when attached to an electrical node on the power system and through observations on voltage, current and phase shift with a step load change, determines the effective Thevenin or Norton impedance at the point of test. This thesis includes discussion of the theory and design process that enables the determination of an equivalent circuit, software development using National Instruments' LabView software development package and suggestions for future development.
The purpose of this thesis is to produce a device that can …

Distance Estimation Between Transceivers Over Short Distances, Karsten Lowe

All Theses

Three methods for determining distances between a user and a fixed coordinate system are considered. One system is based on 802.11g packet communications, another on HF radio carrier frequency interference, and the final system on a signal transmitted over a radio channel. Emphasis is placed on the use of these systems in indoor, building-sized environments. Tests are performed to examine the effectivness and potential of these methods. None of the suggested methods are determined to be usable. Reasons for their failure are examined.

Wafer Probe And Package Test Failure Analysis, Deepa Kalva

All Theses

In recent years, NAND flash memory has gained a lot of momentum in the semiconductor industry and has become an ideal choice for many consumer and communication products. One of the key elements in the successful production of NAND flash memory is to incorporate elaborate testing methods to ensure functionality and reliability before the part reaches the customer. This in turn necessitates the evaluation and understanding of different failure mechanisms, and the development of methodologies to correct problems.
In this thesis, failure analysis was performed on NAND flash memory at wafer and package level. This involved massive data collection and …

On The Stability Of Region Count In The Parameter Space Of Image Analysis Methods, Li Yu

All Dissertations

In this dissertation a novel bottom-up computer vision approach is proposed. This approach is based upon quantifying the stability of the number of regions or count in a multi-dimensional parameter scale-space. The stability analysis comes from the properties of flat areas in the region count space generated through bottom-up algorithms of thresholding and region growing, hysteresis thresholding, variance-based region growing. The parameters used can be threshold, region growth, intensity statistics and other low-level parameters. The advantages and disadvantages of top-down, bottom-up and hybrid computational models are discussed. The approaches of scale-space, perceptual organization and clustering methods in computer vision are …