Engineering Commons^™

Using Structured P2p Overlay Networks To Build Content Sensitive Communities, Paul Stacey, Damon Berry, Eugene Coyle

Conference papers

This paper details a proposed peer-to-peer system, which allows a user to join communities of other like-minded users in order to exchange files. Utilising the routing capabilities of Pastry, the proposed system includes an indexing service, which facilitates the creation of virtual rendezvous points for users with similar interests (manifested by shared keywords). Users are described by the content they store. By using vector space modelling techniques users can be grouped together to form content sensitive communities. The system is built to serve as the basis for a distributed archive of research papers. The system is designed to improve the …

Combining Capacitor/Inductor And Idling Asynchronous Motor In Design Of A System For Balance Of A Large Two-Phase Industrial Load Over Three Phases, Eugene Coyle, M Farrell, W. J. Campbell

Conference papers

This paper describes the design and implementation of a new solution to power quality problems associated with large unbalanced nonlinear loads at fine glass furnace production utilities. Such furnaces use two-phase electricity for reasons of enhanced temperature control and in order to maintain consistency of glass viscosity. A significant risk of power failure is introduced due to this requirement. The furnace load is also nonlinear in nature, due to temperature control by electronic power switching. This gives rise to risks associated with high harmonic distortion. A new method in design of filters to alleviate problems associated with this type of …

Photonic Band Gap Analysis Using Finite-Difference Frequency-Domain Method, Shangping Guo, Feng Wu, Sacharia Albin

Electrical & Computer Engineering Faculty Publications

A finite-difference frequency-domain (FDFD) method is applied for photonic band gap calculations. The Maxwell’s equations under generalized coordinates are solved for both orthogonal and non-orthogonal lattice geometries. Complete and accurate band gap information is obtained by using this FDFD approach. Numerical results for 2D TE/TM modes in square and triangular lattices are in excellent agreements with results from plane wave method (PWM). The accuracy, convergence and computation time of this method are also discussed.

Delivery Of Wireless Ad Hoc Services Using Jini, Sinead Cummins

Theses

Traditionally, networks were planned infrastructures consisting mainly ot desktop machines and servers. As a result of the careful planning carried out prior to their construction, these networks were easily managed and controlled by network administrators. Today these networks are joined by cell phones, PDAs and other handheld devices as well as a host of sensors. This has led to a migration from traditional networks to ad hoc networks.

One way to envisage what this new environment will be like is to imagine what life will be like at the edge of the network. Today the edge mostly consists ot clients …

Survivable Multicasting In Wdm Optical Networks, Sateesh Chandra Shekhar

LSU Master's Theses

Opportunities abound in the global content delivery service market and it is here that multicasting is proving to be a powerful feature. In WDM networks, optical splitting is widely used to achieve multicasting. It removes the complications of optical-electronic-optical conversions [1]. Several multicasting algorithms have been proposed in the literature for building light trees. As the amount of fiber deployment increases in networks, the risk of losing large volumes of data traffic due to a fiber span cut or due to node failure also increases. In this thesis we propose heuristic schemes to make the primary multicast trees resilient to …

Iddq Testing Of A Cmos First Order Sigma-Delta Modulator Of An 8-Bit Oversampling Adc, Anand K. Chamakura

LSU Master's Theses

This work presents IDDQ testing of a CMOS first order sigma-delta modulator of an 8-bit oversampling analog-to-digital converter using a built-in current sensor [BICS]. Gate-drain, source-drain, gate-source and gate-substrate bridging faults are injected using fault injection transistors. All the four faults cause varying fault currents and are successfully detected by the BICS at a good operation speed. The BICS have a negligible impact on the performance of the modulator and an external pin is provided to completely cut-off the BICS from the modulator. The modulator was designed and fabricated in 1.5 μm n-well CMOS process. The decimator was designed on …

Comparative Analysis Of Bragg Fibers, Shangping Guo, Sacharia Albin, Robert S. Rogowski

Electrical & Computer Engineering Faculty Publications

In this paper, we compare three analysis methods for Bragg fibers, viz. the transfer matrix method, the asymptotic method and the Galerkin method. We also show that with minor modifications, the transfer matrix method is able to calculate exactly the leakage loss of Bragg fibers due to a finite number of H/L layers. This approach is more straightforward than the commonly used Chew’s method. It is shown that the asymptotic approximation condition should be satisfied in order to get accurate results. The TE and TM modes, and the band gap structures are analyzed using Galerkin method.

Quantum Lattice Representation Of Dark Solitons, George Vahala, Linda L. Vahala, Jeffrey Yepez

Electrical & Computer Engineering Faculty Publications

The nonlinear Schrodinger (NLS) equation in a self-defocusing Kerr medium supports dark solitons. Moreover the mean field description of a dilute Bose-Einstein condensate (BEC) is described by the Gross-Pitaevskii equation, which for a highly anisotropic (cigar-shaped) magnetic trap reduces to a one-dimensional (1D) cubic NLS in an external potential. A quantum lattice algorithm is developed for the dark solitons. Simulations are presented for both black (stationary) solitons as well as (moving) dark solitons. Collisions of dark solitons are compared with the exact analytic solutions and coupled dark-bright vector solitons are examined. The quantum algorithm requires 2 qubits per scalar field …

Characterization Of Human Metal Esd Reference Discharge Event And Correlation Of Generator Parameters To Failure Levels-Part Ii: Correlation Of Generator Parameters To Failure Levels, Kai Wang, David Pommerenke, Ramachandran Chundru, Thomas Van Doren, Jiu Sheng Huang, Federico Centola

Electrical and Computer Engineering Faculty Research & Creative Works

Most electrostatic discharge (ESD) generators are built in accordance with the IEC 61000-4-2 specifications. It is shown, that the voltage induced in a small loop correlates with the failure level observed in an ESD failure test on the systems comprised of fast CMOS devices, while rise time and derivative of the discharge current did not correlate well. The electric parameters of typical ESD generators and ESD generators that have been modified to reflect the current and field parameters of the human metal reference event are compared and the effect on the failure level of fast CMOS electronics is investigated. The …

Data Mining Of Substation Relay Data, Badrul H. Chowdhury, Mythili Chaganti

Electrical and Computer Engineering Faculty Research & Creative Works

Data mining aims to make sense of data by revealing meaningful relationships. This paper discusses data mining techniques applied to data recorded by over current relays at several substations. The purpose is to classify faults, verify relay settings and determine fault induced trip per substations. One of the most demanding tasks at hand is to study the data residing in the relays on a statistical basis. C4.5 approach of data mining (decision tree induction) is discussed in this paper.

Detection Of Basal Cell Carcinoma Using Electrical Impedance And Neural Networks, Rohit Dua, Daryl G. Beetner, William V. Stoecker, Donald C. Wunsch

Electrical and Computer Engineering Faculty Research & Creative Works

Variations in electrical impedance over frequency might be used to distinguish basal cell carcinoma (BCC) from benign skin lesions, although the patterns that separate the two are nonobvious. Artificial neural networks (ANNs) may be good pattern classifiers for this application. A preliminary study to show the potential of neural networks to distinguish benign from malignant skin lesions using electrical impedance is presented. Electrical impedance was measured in vivo from 1 kHz to 1 MHz at five virtual depths on 18 BCC and 16 benign or premalignant lesions. A feed-forward neural network was trained using back propagation to classify these lesions. …

Electromagnetic Analysis For Vehicle Antenna Development Using Method Of Auxiliary Sources, David Pommerenke, Kai Xiao, R. S. Zaridze, D. G. Kakulia, K. N. Tavzarashvili, G. N. Ghvedashvili

Electrical and Computer Engineering Faculty Research & Creative Works

In paper [l] the electromagnetic analysis of large semi-open structures like vehicles was presented formulated as scattering problem, illuminated by a wide range of incident EM fields. The effect of resonances within the semi-open structure on the RCS, near fields and pattem of reradiated fields had been shown. In this paper the interaction of the entire semi-open structure on the performance of an antenna is considered together with the investigation of near field distributions inside the cavity. The Method of Auxiliary Sources (MAS) [2] is utilized. For a simple geometry the results are compared to measurements.

Navigation Of Mobile Sensors Using Pso And Embedded Pso In A Fuzzy Logic Controller, Ganesh K. Venayagamoorthy, Sheetal Doctor

Electrical and Computer Engineering Faculty Research & Creative Works

This paper presents novel structures for optimization and communication of a swarm of mobile sensors or robots for maximizing local and global tasks such as firefighting, landmine detection, radioactivity detection, etc. The navigation of the sensors is carried out using two strategies. The first strategy is based on particle swarm optimization (PSO) and the second strategy is based on a swarm of fuzzy logic based controllers. In addition, the membership functions and the rules of the fuzzy logic controller (FLC) are optimized using the PSO algorithm. Navigation of mobile sensors is considered in this paper to locate desirable target sources …

Neural Network Controller For Manipulation Of Micro-Scale Objects, Vijayakumar Janardhan, Pingan He, Jagannathan Sarangapani

Electrical and Computer Engineering Faculty Research & Creative Works

A novel reinforcement learning-based neural network (RLNN) controller is presented for the manipulation and handling of micro-scale objects in a microelectromechanical system (MEMS). In MEMS, adhesive, surface tension, friction and van der Waals forces are dominant. Moreover, these forces are typically unknown. The RLNN controller consists of an action NN for compensating the unkoown system dynamics, and a critic NN to tune the weights of the action NN. Using the Lyapunov approach, the uniformly ultimate houndedness (UUB) of the closed-loop tracking error and weight estimates are shown by using a novel weight updates. Simulation results are presented to substantiate the …

Neuroidentification Of System Parameters Of The Upfc In A Multimachine Power System, Radha P. Kalyani, Ganesh K. Venayagamoorthy

Electrical and Computer Engineering Faculty Research & Creative Works

The crucial factor affecting the modern power systems today is load flow control. The Unified Power Flow Controller is an effective means for controlling the power flow. The UPFC is controlled conventionally using PI controllers. This paper presents the designs of neuroidentifiers that models the system dynamics one-time step ahead making the pathway for the design of adaptive neurocontrollers. Two neuroidentifiers are used for identifying the nonlinear dynamics of a multimachine power system and UPFC, one neuroidentifier for the shunt inverter and another for the series inverter. Simulation results carried out in the PSCAD/EMTDC environments on multimachine power system are …

Calibrating An Intracranial Pressure Dynamics Model With Clinical Data - A Progress Report, Wayne W. Wakeland, James Mcnames, Brahm Goldstein

Complex Systems Faculty Publications and Presentations

We describe the calibration of a computer model of intracranial pressure (ICP) dynamics to correspond with annotated clinical data taken from a patient being treated for elevated ICP due to a traumatic brain injury. The research protocol employed during treatment includes adjusting the elevation of the head of the bed, adjusting the ventilator settings to induce mild hyperventilation and hypoventilation, and adjusting the height of the cerebrospinal fluid drainage system. The model behavior corresponds to the experimental data quite well in the case of the changing the head of the bed, but less well in the case of changing the …

First Order Sigma-Delta Modulator Of An Oversampling Adc Design In Cmos Using Floating Gate Mosfets, Syam Prasad Sbs Kommana

LSU Master's Theses

We report a new architecture for a sigma-delta oversampling analog-to-digital converter (ADC) in which the first order modulator is realized using the floating gate MOSFETs at the input stage of an integrator and the comparator. The first order modulator is designed using an 8 MHz sampling clock frequency and implemented in a standard 1.5µm n-well CMOS process. The decimator is an off-chip sinc-filter and is programmed using the VERILOG and tested with Altera Flex EPF10K70RC240 FPGA board. The ADC gives an 8-bit resolution with a 65 kHz bandwidth.

Design And Performance Of Electric Shock Absorber, Oly D. Paz

LSU Master's Theses

The electric shock absorber is a device that converts the kinetic energy of an oscillating object into electric energy. This kinetic energy is normally dumped in a form of thermal energy in a conventional, mechanical shock absorber. The electric shock absorber consists of a permanent magnet linear synchronous generator (PMLSG), a spring, and an electric energy accumulator. The major goal of the project is to design and analyze the operation of an electric shock absorber. In order to define the initial requirements that the electric shock absorber has to satisfy, the construction and performance of currently used shock absorbers were …

Testing A Cmos Operational Amplifier Circuit Using A Combination Of Oscillation And Iddq Test Methods, Pavan K. Alli

LSU Master's Theses

This work presents a case study, which attempts to improve the fault diagnosis and testability of the oscillation testing methodology applied to a typical two-stage CMOS operational amplifier. The proposed test method takes the advantage of good fault coverage through the use of a simple oscillation based test technique, which needs no test signal generation and combines it with quiescent supply current (IDDQ) testing to provide a fault confirmation. A built in current sensor (BICS), which introduces insignificant performance degradation of the circuit-under-test (CUT), has been utilized to monitor the power supply quiescent current changes in the CUT. The testability …

Zooplankton Visualization System: Design And Real-Time Lossless Image Compression, Dattatreya Reddy Tetala Satya Surya

LSU Master's Theses

In this thesis, I present a design of a small, self-contained, underwater plankton imaging system. I base the imaging system’s design on an embedded PC architecture based on PC/104-Plus standards to meet the compact size and low power requirements. I developed a simple graphical user interface to run on a real-time operating system to control the imaging system. I also address how a real-time image compression scheme implemented on an FPGA chip speeds up image transfer speeds of the imaging system. Since lossless compression of the image is required in order to retain all image details, I began with an …

An Evaluation Of Multiple Branch Predictor And Trace Cache Advanced Fetch Unit Designs For Dynamically Scheduled Superscalar Processors, Slade S. Maurer

LSU Master's Theses

Semiconductor feature size continues to decrease permitting superscalar microprocessors to continue to increase the number of functional units available for execution. As the instruction issue width increases beyond the five instruction average basic block size of integer programs, more than one basic block must be issued per cycle to continue to increase instructions per cycle (IPC) performance. Researchers have created methods of fetching instructions beyond the first taken branch to overcome the bottleneck created by the limitations of conventional single branch predictors. We compare the performance of the multiple branch prediction (MBP) and trace cache (TC) fetch unit optimization methods. …

Watermarking Using Decimal Sequences, Navneet Kumar Mandhani

LSU Master's Theses

This thesis introduces the use of decimal sequences in watermarking to hide information for authentication. The underlying system is based on code division multiple access (CDMA), which is a form of spread spectrum communication. Different algorithms for the use of decimal sequences have been formulated for use in black and white images. The watermark is spread across the carrier image by using the d- sequences of optimal period and retrieval is made by the use of correlation. Matlab version 6.5 was used to implement the algorithms discussed in this thesis. The advantage of using d-sequences over PN sequences is that …

A Comparison Of System Dynamics And Agent-Based Simulationapplied To The Study Of Cellular Receptor Dynamics, Wayne W. Wakeland, Edward J. Gallaher, Louis Macovsky, C. Athena Aktipis

Complex Systems Faculty Publications and Presentations

Cellular receptor dynamics are often analyzed using differential equations, making system dynamics (SD) a candidate methodology. In some cases it may be useful to model the phenomena at the biomolecular level, especially when concentrations and reaction probabilities are low and might lead to unexpected behavior modes. In such cases, agent-based simulation (ABS) may be useful. We show the application of both SD and ABS to simulate non-equilibrium ligand-receptor dynamics over a broad range of concentrations, where the probability of interaction varies from low to very low. Both approaches offer much to the researcher and are complementary. We did not find …

Using Optimization To Calibrate Models Of Intracranial Pressure Dynamics To Patients With Intracranial Hypertension, Wayne W. Wakeland, A. Bulbul, Mateo Aboy, James Mcnames, Brahm Goldstein

Complex Systems Faculty Publications and Presentations

Aim: Automatically calibrate ICP Dynamic model to a specific patients.

Method: Use optimization algorithm to estimate parameter values (ICP, compliances, resistances) that minimize the squared error in predicted ICP.

Results: Estimated parameter values are plausible and improve predicted ICP. Optimization time for 18 minute episode = 2.5 min. for 1 parameter, 10 to 200 min. for multiple simultaneous parameters (too long).

Bluetooth Enabled Ad-Hoc Networks: Performance Evaluation Of A Self-Healing Scatternet Formation Protocol, Rade Trimceski

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

Bluetooth wireless technology is a robust short-range communications system designed for low power (10 meter range) and low cost. It operates in the 2.4 GHz Industrial Scientific Medical (ISM) band and it employs two techniques for minimizing interference: a frequency hopping scheme which nominally splits the 2.400 - 2.485 GHz band in 79 frequency channels and a time division duplex (TDD) scheme which is used to switch to a new frequency channel on 625 μs boundaries. During normal operation a Bluetooth device will be active on a different frequency channel every 625 μs, thus minimizing the chances of continuous interference …

Stimulation Of Capacitative Calcium Entry In Hl-60 Cells By Nanosecond Pulsed Electric Fields, Jody A. White, Peter F. Blackmore, Karl H. Schoenbach, Stephen J. Beebe

Bioelectrics Publications

Nanosecond pulsed electric fields (nsPEFs) are hypothesized to affect intracellular structures in living cells providing a new means to modulate cell signal transduction mechanisms. The effects of nsPEFs on the release of internal calcium and activation of calcium influx in HL-60 cells were investigated by using real time fluorescent microscopy with Fluo-3 and fluorometry with Fura-2. nsPEFs induced an increase in intracellular calcium levels that was seen in all cells. With pulses of 60 ns duration and electric fields between 4 and 15 kV/cm, intracellular calcium increased 200-700 nM, respectively, above basal levels (similar to100 nM), while the uptake of …

High-Field Quasi-Ballistic Transport In Short Carbon Nanotubes, Ali Javey, Jing Guo, Magnus Paulsson, Qian Wang, Mark S. Lundstrom, Hongjie Dai, David Mann

Department of Electrical and Computer Engineering Faculty Publications

Single walled carbon nanotubes with Pd Ohmic contacts and lengths ranging from several microns down to 10 nm are investigated by electron transport experiments and theory. The mean-free path (MFP) for acoustic phonon scattering is estimated to be lap ~300  nm, and that for optical phonon scattering is lop ~15  nm. Transport through very short (~10  nm) nanotubes is free of significant acoustic and optical phonon scattering and thus ballistic and quasiballistic at the low- and high-bias voltage limits, respectively. High currents of up to 70   μA can flow through a short nanotube. Possible mechanisms for the eventual electrical breakdown …

A Three-Dimensional Quantum Simulation Of Silicon Nanowire Transistors With The Effective Mass Approximation, Jing Wang, Eric Polizzi, Mark S. Lundstrom

Department of Electrical and Computer Engineering Faculty Publications

The silicon nanowire transistor (SNWT) is a promising device structure for future integrated circuits, and simulations will be important for understanding its device physics and assessing its ultimate performance limits. In this work, we present a three-dimensional (3D) quantum mechanical simulation approach to treat various SNWTs within the effective-mass approximation. We begin by assuming ballistic transport, which gives the upper performance limit of the devices. The use of a mode space approach (either coupled or uncoupled) produces high computational efficiency that makes our 3D quantum simulator practical for extensive device simulation and design. Scattering in SNWTs is then treated by …

Monolithic Integration Of Dual Optical Elements On High Power Semicond, Laurent Vaissie

Electronic Theses and Dissertations

This dissertation investigates the monolithic integration of dual optical elements on high power semiconductor lasers for emission around 980nm wavelength. In the proposed configuration, light is coupled out of the AlGaAs/GaAs waveguide by a low reflectivity grating coupler towards the substrate where a second monolithic optical element is integrated to improve the device performance or functionality. A fabrication process based on electron beam lithography and plasma etching was developed to control the grating coupler duty cycle and shape. The near-field intensity profile outcoupled by the grating is modeled using a combination of finite-difference time domain (FDTD) analysis of the nonuniform …

General Interference Suppression Technique For Diversity Wireless Rece, Tianyu Yang

Electronic Theses and Dissertations

The area of wireless transceiver design is becoming increasingly important due to the rapid growth of wireless communications market as well as diversified design specifications. Research efforts in this area concentrates on schemes that are capable of increasing the system capacity, providing reconfigurability/reprogrammability and reducing the hardware complexity. Emerging topics related to these goals include Software Defined Radio, Multiple-Input-Multiple-Output (MIMO) Systems, Code Division Multiple Access, Ultra-Wideband Systems, etc. This research adopts space diversity and statistical signal processing for digital interference suppression in wireless receivers. The technique simplifies the analog front-end by eliminating the anti-aliasing filters and relaxing the requirements for …