Digital Commons Network^™

Empirical Study Of An Unconstrained Modified Particle Swarm Optimization, Ganesh K. Venayagamoorthy, Phillip W. Moore

Electrical and Computer Engineering Faculty Research & Creative Works

In this paper, an unconstrained modified particle swarm optimization (UMPSO) algorithm is introduced and studied empirically. Four well known benchmark functions, with asymmetric initial position values, are used as testing functions for the UMPSO algorithm. The UMPSO is a variation of the canonical PSO in which the velocity and position is unconstrained, an additional strategic component is added, and the social component term has been modified. The strategy component is used instead of varying parameters or mutation to enhance diversity in the swarm during the search. The UMPSO algorithm is then compared to results obtained from the constrained canonical PSO …

Mobile Speed Classification For Cellular Systems Over Frequency Selective Rician Fading Channels, Y. Rosa Zheng, Chengshan Xiao

Electrical and Computer Engineering Faculty Research & Creative Works

In this paper, a new algorithm is proposed for estimating mobile speed of cellular systems over frequency selective Rician fading channels. Theoretical analysis is first derived and practical algorithm is proposed based on the analytical results. The algorithm employs a modified auto-covariance of received signal power to estimate the speed of mobiles. The algorithm is based on the received signals which contain unknown transmitted data, unknown frequency selective multipaths including line-of-sight(LOS) component, and random receiver noise. The algorithm works very well for frequency selective Rician fading channels with large ranges of Rice factor and angle of arrival of the LOS …

Neural Network-Based Output Feedback Controller For Lean Operation Of Spark Ignition Engines, Brian C. Kaul, Jagannathan Sarangapani, J. A. Drallmeier, Jonathan B. Vance, Pingan He

Electrical and Computer Engineering Faculty Research & Creative Works

Spark ignition (SI) engines running at very lean conditions demonstrate significant nonlinear behavior by exhibiting cycle-to-cycle dispersion of heat release even though such operation can significantly reduce NOx emissions and improve fuel efficiency by as much as 5-10%. A suite of neural network (NN) controller without and with reinforcement learning employing output feedback has shown ability to reduce the nonlinear cyclic dispersion observed under lean operating conditions. The neural network controllers consists of three NN: a) A NN observer to estimate the states of the engine such as total fuel and air; b) a second NN for generating virtual input; …

Novel Sum-Of-Sinusoids Simulation Models For Rayleigh And Rician Fading Channels, Chengshan Xiao, Y. Rosa Zheng, N. C. Beaulieu

Electrical and Computer Engineering Faculty Research & Creative Works

The statistical properties of Clarke's fading model with a finite number of sinusoids are analyzed, and an improved reference model is proposed for the simulation of Rayleigh fading channels. A novel statistical simulation model for Rician fading channels is examined. The new Rician fading simulation model employs a zero-mean stochastic sinusoid as the specular (line-of-sight) component, in contrast to existing Rician fading simulators that utilize a non-zero deterministic specular component. The statistical properties of the proposed Rician fading simulation model are analyzed in detail. It is shown that the probability density function of the Rician fading phase is not only …

On Discrete-Time Modeling Of Time-Varying Wssus Fading Channels, Christian Sgraja, Chengshan Xiao

Electrical and Computer Engineering Faculty Research & Creative Works

In this paper, we consider the serial concatenation of linear time-varying (LTV) systems and its impact on the discrete-time modeling of wide-sense stationary uncorrelated scattering (WSSUS) fading channels. By deriving an expression for the composite impulse response of the overall concatenated system, we find that unlike the time-invariant case, the concatenation of LTV systems is not commutative, i. e., the order of arrangement affects the overall impulse response. This has significant impact when a digital transmission over a time-varying fading channel, which is an LTV channel, is represented by an equivalent discrete-time model that incorporates both transmitter and receiver filters. …

Adaptive Distributed Fair Scheduling And Its Implementation In Wireless Sensor Networks, Maciej Jan Zawodniok, Jagannathan Sarangapani, Steve Eugene Watkins, James W. Fonda

Electrical and Computer Engineering Faculty Research & Creative Works

A novel adaptive and distributed fair scheduling (ADFS) scheme for wireless sensor networks is shown through hardware implementation. In contrast to simulation, hardware evaluation provides valuable feedback to protocol and hardware development process. The proposed protocol focuses on quality-of-service (QoS) issues to address flow prioritization. Thus, when nodes access a shared channel, the proposed ADFS allocates the channel bandwidth proportionally to the weight, or priority, of the packet flows. Moreover, ADFS allows for dynamic allocation of network resources with little added overhead. Weights are initially assigned using user specified QoS criteria. These weights are subsequently updated as a function of …

A Non-Isotropic Model For Mobile-To-Mobile Fading Channel Simulations, Y. Rosa Zheng

Electrical and Computer Engineering Faculty Research & Creative Works

Accurate modeling of the mobile-to-mobile fading channel is critical not only to physical layer transceiver design but also to the design and performance of link and network layers. A two-dimensional nonisotropic scattering model is developed in this paper, which adopts the von Mises probability density function for the angle of departure surrounding the transmitter and the angle of arrival surrounding the receiver. This model includes the isotropic scattering channel and the base-to-mobile channel as special cases. An efficient computer simulation model is also developed to generate the non-isotropic scattering channel impulse responses. Statistical properties of the non-isotropic mobile-to-mobile channels are …

Adaptive And Probabilistic Power Control Algorithms For Dense Rfid Reader Network, Kainan Cha, Anil Ramachandran, Jagannathan Sarangapani

Electrical and Computer Engineering Faculty Research & Creative Works

In radio frequency identification (RFID) systems, the detection range and read rates may suffer from interferences between high power devices such as readers. In dense networks, this problem grows severely and degrades system performance. In this paper, we investigate feasible power control schemes to ensure overall coverage area of the system while maintaining a desired data rate. The power control should dynamically adjust the output power of a RFID reader by adapting to the noise level seen during tag reading and acceptable signal-to-noise ratio (SNR). We present a novel distributed adaptive power control (DAPC) and probabilistic power control (PPC) as …

Advanced Detection And Coding Techniques For Nonlinear Intersymbol Interference Cancellation In 40 Gb/S Systems, B. Vasic, I. B. Djordjevic, Vittal S. Rao

Electrical and Computer Engineering Faculty Research & Creative Works

No abstract provided.

Comparison Of Two Optimal Control Strategies For A Grid Independent Photovoltaic System, Richard L. Welch, Ganesh K. Venayagamoorthy

Electrical and Computer Engineering Faculty Research & Creative Works

This paper presents two optimal control strategies for a grid independent photovoltaic system consisting of a PV collector array, a storage battery, and loads (critical and non-critical loads). The first strategy is based on Action Dependent Heuristic Dynamic Programming (ADHDP), a model-free adaptive critic design (ACD) technique which optimizes the control performance based on a utility function. ADHDP critic network is used in a PV system simulation study to train an action neural network (optimal neurocontroller) to provide optimal control for varying PV system output energy and loadings. The second optimal control strategy is based on a fuzzy logic controller …

Emc Expert Systems For Evaluating Automotive Designs, Todd H. Hubing

Electrical and Computer Engineering Faculty Research & Creative Works

The automobiles of the future are being designed on computers and a significant amount of performance and safety testing is done using computer models. by the time the first hardware prototype is built, many critical design decisions affecting intersystem and intra-system electromagnetic compatibility (EMC) have been made. Therefore, it is becoming increasingly important to perform the first EMC design review well before any hardware is available to test. Automotive EMC expert systems examine the relevant aspects of an automotive design while it is still on the computer to spot design features that are likely to cause EMC problems. © 2006 …

Space-Time Block Coding For Multiple Transmit Antennas Over Time-Selective Fading Channels, Ioannis Erotokritou

LSU Master's Theses

The last decade we have witnessed an extraordinary growing interest in the field of wireless communications. Wireless industry has recently turned into a technology known as Multiple-Input Multiple-Output (MIMO) to minimize errors and optimize data speed. This is done by using multiple transmit and receive antennas, as well as appropriate space-time block code techniques. Due the fact that time-selective fading channels exist, the assumption that the channel is being static over the length of the codeword does not apply in this thesis. The channel state varies over the number of signal intervals, and in such case the orthogonality of the …

Ber Variation In An Uwb Ofdm Mimo Communications System Based On Measurements Made In A Picocell Wireless Environment, Conor Downing, Pat Chambers, Hussein Baher

Conference papers

A picocell UWB MIMO communications system model is considered which has five orthogonal sub-channels, each with its own OFDM signal. The effect of removing the various channel impulse response components which arise due to the multi-path propogation, a phenomenon characteristic of wide band transmission, is considered. This is a measurement based analysis where the measurements, themselves, were made, in a specially constructed enclosure which had reflective surfaces, using specially designed UWB antennas.

Design Of A Wide-Band Printed Antenna Using A Genetic Algorithm On An Array Of Overlapping Sub-Patches, Matthias John, Max Ammann

Conference papers

No abstract provided.

An Approach To Teaching Pid Controller Tuning, Aidan O'Dwyer

Conference papers

This paper discusses an approach to the teaching of PID controller tuning methods to students in control engineering at Dublin Institute of Technology. The method involves analytically calculating the gain margin, phase margin and maximum sensitivity for PI and PID controlled systems whose process is modelled in first order lag plus time delay (FOLPD) form. Students can examine the performance of many tuning rules from graphical results, allowing insight to be developed as to the most rational choice of the tuning rule for the application. Some preliminary work done to develop an expert system to allow a greater automation of …

Reducing Energy Costs By Optimizing Controller Tuning, 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 technique, it is necessary to adjust the controller parameters according to the nature of the process. 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 tuning, based on process information). Such tuning rules allow the easy set up of controllers to achieve optimum performance at commissioning. Importantly, they allow ease of re-commissioning if the characteristics of the process change. The paper outlines the results …

Communication Blades: Modular Communications For Tangible And Embedded Interfaces, Karun Kumar Kallakuri

LSU Master's Theses

Bladed Tiles is a modular hardware toolkit for building tangible and embedded interface devices. It includes “function blades” and “interaction tiles,” which can provide a flexible, inexpensive, open-ended platform for constructing a wide variety of tangible and embedded interfaces. In this paper, we propose Communication Blades. These are a class of electronic modules with varied computational capabilities for interfacing devices built using bladed tiles toolkit and also for interfacing embedded devices as adapters with external communication networks. These blades provide flexibility by offering the ability to select between different communication technologies and connectivity by providing devices with interoperability over different …

A Novel Robust Mel-Energy Based Voice Activity Detector For Nonstationary Noise And Its Application For Speech Waveform Compression, Syed, Q. Waheeduddin

LSU Master's Theses

The voice activity detection (VAD) is crucial in all kinds of speech applications. However, almost all existing VAD algorithms suffer from the nonstationarity of both speech and noise. To combat this difficulty, we propose a new voice activity detector, which is based on the Mel-energy features and an adaptive threshold related to the signal-to-noise ratio (SNR) estimates. In this thesis, we first justify the robustness of the Bayes classifier using the Mel-energy features over that using the Fourier spectral features in various noise environments. Then, we design an algorithm using the dynamic Mel-energy estimator and the adaptive threshold which depends …

Improved Content Based Watermarking For Images, Arvind Kumar Parthasarathy

LSU Master's Theses

Due to improvements in imaging technologies and the ease with which digital content can be created and manipulated, there is need for the copyright protection of digital content. It is also essential to have techniques for authentication of the content as well as the owner. To this end, this thesis proposes a robust and transparent scheme of watermarking that exploits the human visual systems’ sensitivity to frequency, along with local image characteristics obtained from the spatial domain, improving upon the content based image watermarking scheme of Kay and Izquierdo. We implement changes in this algorithm without much distortion to the …

Optical Characterization Of Electrochemically Self-Assembled Compound Semiconductor Nanowires, Sivakumar Ramanathan

Theses and Dissertations

Semiconductor nanowires have attracted considerable attention as possible source for lasers and optical storage media. We report the fabrication and optical characterization of ZnO and CdS nanowires. The former are produced by electrochemical deposition of Zn inside nanoporous alumina films containing regimented arrays of 10nm, 25nm and 50 nm diameter pores, followed by room temperature chemical oxidization. Fluorescence spectroscopy shows different characteristics associated with different sample diameter. The 50 nm ZnO nanowires show an exciton recombination peak and an additional peak related to the deep trap levels. 25 nm ZnO nanowires show a only the exciton recombination peak, which is …

Forensic Tools For Mobile Phone Subscriber Identity Modules, Wayne Jansen, Rick Ayers

Journal of Digital Forensics, Security and Law

Mobile phones and other handheld devices incorporating cellular capabilities, such as Personal Digital Assistants, are ubiquitous. Besides placing calls, these devices allow users to perform other useful tasks, including text messaging and phonebook entry management. When cell phones and cellular devices are involved in a crime or other incident, forensic specialists require tools that allow the proper retrieval and speedy examination of data present on the device. For devices conforming to the Global System for Mobile Communications (GSM) standards, certain data such as dialed numbers, text messages, and phonebook entries are maintained on a Subscriber Identity Module (SIM). This paper …

Designing A Data Warehouse For Cyber Crimes, Il-Yeol Song, John D. Maguire, Ki Jung Lee, Namyoun Choi, Xiaohua Hu, Peter Chen

Journal of Digital Forensics, Security and Law

One of the greatest challenges facing modern society is the rising tide of cyber crimes. These crimes, since they rarely fit the model of conventional crimes, are difficult to investigate, hard to analyze, and difficult to prosecute. Collecting data in a unified framework is a mandatory step that will assist the investigator in sorting through the mountains of data. In this paper, we explore designing a dimensional model for a data warehouse that can be used in analyzing cyber crime data. We also present some interesting queries and the types of cyber crime analyses that can be performed based on …

The 2006 Analysis Of Information Remaining On Disks Offered For Sale On The Second Hand Market, Andy Jones, Craig Valli, Iain Sutherland, Paula Thomas

Journal of Digital Forensics, Security and Law

All organisations, whether in the public or private sector, use computers for the storage and processing of information relating to their business or services, their employees and their customers. A large proportion of families and individuals in their homes now also use personal computers and, both intentionally and inadvertently, often store on those computers personal information. It is clear that most organisations and individuals continue to be unaware of the information that may be stored on the hard disks that the computers contain, and have not considered what may happen to the information after the disposal of the equipment.

In …

The Design Of An Undergraduate Degree Program In Computer & Digital Forensics, Gary C. Kessler, Michael E. Schirling

Journal of Digital Forensics, Security and Law

Champlain College formally started an undergraduate degree program in Computer & Digital Forensics in 2003. The underlying goals were that the program be multidisciplinary, bringing together the law, computer technology, and the basics of digital investigations; would be available as on online and oncampus offering; and would have a process-oriented focus. Success of this program has largely been due to working closely with practitioners, maintaining activity in events related to both industry and academia, and flexibility to respond to ever-changing needs. This paper provides an overview of how this program was conceived, developed, and implemented; its evolution over time; and …

A Curriculum For Teaching Information Technology Investigative Techniques For Auditors, Grover S. Kearns

Journal of Digital Forensics, Security and Law

Recent prosecutions of highly publicized white-collar crimes combined with public outrage have resulted in heightened regulation of financial reporting and greater emphasis on systems of internal control. Because both white-collar and cybercrimes are usually perpetrated through computers, internal and external auditors’ knowledge of information technology (IT) is now more vital than ever. However, preserving digital evidence and investigative techniques, which can be essential to fraud examinations, are not skills frequently taught in accounting programs and instruction in the use of computer assisted auditing tools and techniques – applications that might uncover fraudulent activity – is limited. Only a few university-level …

Is Forensic Computing A Profession? Revisiting An Old Debate In A New Field, Bernd C. Stahl

Journal of Digital Forensics, Security and Law

Forensic Computing is a new and quickly developing field. It is in the process of becoming an academic discipline or sub-discipline with all the features from full undergraduate and postgraduate course provision to conferences and journals. An important question in this process of turning into an established discipline is whether it will coincide with the recognition of the graduates as professionals. This paper hopes to stimulate the debate as to whether forensic computing is or should be a discipline. In order to approach this question, the paper will discuss the concept of forensic computing including the most salient topics of …

The Role Of Power And Negotiation In Online Deception, Chad Albrecht, Conan C. Albrecht, Jonathan Wareham, Paul Fox

Journal of Digital Forensics, Security and Law

The purpose of this paper is to advance theoretical understanding of the important role of both power and negotiation during online deception. By so doing, the paper provides insight into the relationship between perpetrator and victim in Internet fraud. The growing prevalence of Internet Fraud continues to be a burden to both society and individuals. In an attempt to better understand Internet fraud and online deception, this article attempts to build an interactive model, based upon the dimensions of power and negotiation from the management and psychology literature. Using the model presented, the article examines the effects of the Internet …

Mapping A Weak Hypercube On An Optical Slab Waveguide, Divya Rengan

LSU Master's Theses

The communication fabric of a parallel processing system is represented as a directed graph. In a weak topology a processor uses at most one incoming edge or one outgoing edge for communication at any given point in time. Currently, the data rate that can be supported on electronic interconnects is reaching its limits. Optical interconnects have been identified as one of the most promising approaches to the growing demands for today's systems. The “medium bandwidth” of an optical waveguide is huge (order of petabits per second for a 1mm2 cross-section optical slab). The challenge lies in utilizing as much of …

Design Of Cmos Lc Voltage Controlled Oscillators, Chetan Shambhulinga Salimath

LSU Master's Theses

This work presents the design and implementation of CMOS LC voltage controlled oscillators. On-chip planar spiral inductors and PMOS inversion mode varactors were utilized to implement the resonator. Two voltage controlled oscillators (VCOs) were realized as a part of this work, one designed to operate at 1.1 GHz while the second at 1.8 GHz. Both VCOs were implemented in a scalable digital CMOS process, with the former in a 1.5 micron CMOS process and the latter in a 0.5 micron technology. A simulation based methodology was adopted to arrive at a simple pi model used to model the metal and …

Study Of And Design Procedure For Dual Circularly Polarized Waveguide Slot Arrays, Lee M. Paulsen

Dissertations, Master's Theses and Master's Reports - Open

For the past sixty years, waveguide slot radiator arrays have played a critical role in microwave radar and communication systems. They feature a well-characterized antenna element capable of direct integration into a low-loss feed structure with highly developed and inexpensive manufacturing processes. Waveguide slot radiators comprise some of the highest performance—in terms of side-lobe-level, efficiency, etc. — antenna arrays ever constructed.

A wealth of information is available in the open literature regarding design procedures for linearly polarized waveguide slots. By contrast, despite their presence in some of the earliest published reports, little has been presented to date on array designs …