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Full-Text Articles in Engineering

Collaborative Routing Algorithm For Wireless Sensor Network Longevity, Shishir Bashyal, Ganesh K. Venayagamoorthy Dec 2007

Collaborative Routing Algorithm For Wireless Sensor Network Longevity, Shishir Bashyal, Ganesh K. Venayagamoorthy

Electrical and Computer Engineering Faculty Research & Creative Works

This study proposes a new parameter for evaluating longevity of wireless sensor networks after showing that the existing parameters do not properly evaluate the performance of algorithms in increasing longevity. This study also proposes an ant inspired Collaborative Routing Algorithm for Wireless Sensor Network Longevity (CRAWL) that has scalability and adaptability features required in most wireless sensor networks. Using the proposed longevity metrics and implementing the algorithm in simulations, it is shown that CRAWL is much more adaptive to non-uniform distribution of available energy in sensor networks. The performance of CRAWL is compared to that of a non-collaborative algorithm. Both …


An Estimation Of Distribution Improved Particle Swarm Optimization Algorithm, Raghavendra V. Kulkarni, Ganesh K. Venayagamoorthy Dec 2007

An Estimation Of Distribution Improved Particle Swarm Optimization Algorithm, Raghavendra V. Kulkarni, Ganesh K. Venayagamoorthy

Electrical and Computer Engineering Faculty Research & Creative Works

PSO is a powerful evolutionary algorithm used for finding global solution to a multidimensional problem. Particles in PSO tend to re-explore already visited bad solution regions of search space because they do not learn as a whole. This is avoided by restricting particles into promising regions through probabilistic modeling of the archive of best solutions. This paper presents hybrids of estimation of distribution algorithm and two PSO variants. These algorithms are tested on benchmark functions having high dimensionalities. Results indicate that the methods strengthen the global optimization abilities of PSO and therefore, serve as attractive choices to determine solutions to …


Electromagnetic Simulation For Inhomogeneous Interconnect And Packaging Structures, Lijun Jiang, Barry J. Rubin, Yuan Liu, Jason D. Morsey, Alina Deustch Dec 2007

Electromagnetic Simulation For Inhomogeneous Interconnect And Packaging Structures, Lijun Jiang, Barry J. Rubin, Yuan Liu, Jason D. Morsey, Alina Deustch

Electrical and Computer Engineering Faculty Research & Creative Works

The paper contains a novel mechanism for full wave electromagnetic simulation of complicated inhomogeneous structures, such as on-chip interconnects, IC packaging, antennas, and scattering objects. It uses only Equivalent Principle based EFIE instead of both EFIE and MFIE to establish the surface integral equations for practical inhomogeneous structure so that a much more simplified formulation process is needed in the EM simulation procedure. To overcome the numerical error of K operator in the formulation, a new analytical solution to the K operator for general full-wave integral equations is provided. Numerical results are demonstrated to verify the proposed algorithm. © 2007 …


Effects Of Electromagnetic Interference On Control Area Network Performance, Fei Ren, Y. Rosa Zheng, Maciej Jan Zawodniok, Jagannathan Sarangapani Nov 2007

Effects Of Electromagnetic Interference On Control Area Network Performance, Fei Ren, Y. Rosa Zheng, Maciej Jan Zawodniok, Jagannathan Sarangapani

Electrical and Computer Engineering Faculty Research & Creative Works

In this paper, the effects of electromagnetic interference (EMI) on control area network (CAN) communications are investigated by hardware experiments. Distinct CAN bit rates, communication cables, and networks are used to test effects of EMI on CAN bus. Waveforms of CAN data frames in EMI environment are observed and analyzed for figuring out details of effects. Experiments show that the EMI pulses frequently encountered in automobile and off-road machinery can cause the reduction of bit rates and errors in high-speed CAN communications. Replacing traditional unshielded parallel communication cables with shielded communication cables is proved to be an effective method of …


The Existence Of Multiple Equilibria In The Upfc Power Injection Model, Mahyar Zarghami, Mariesa Crow Nov 2007

The Existence Of Multiple Equilibria In The Upfc Power Injection Model, Mahyar Zarghami, Mariesa Crow

Electrical and Computer Engineering Faculty Research & Creative Works

This letter shows the existence of multiple equilibria that arise from the use of the state model of the unified power flow controller (UPFC). These multiple equilibria can arise from a common power injection model for the same terminal conditions of shunt bus voltage and series active and reactive power injections. The multiple equilibria result in two or more sets of eigenvalues, some of which may indicate an unstable operating condition. Therefore, the use of the UPFC power injection model must be used with caution to ensure stable operation of the UPFC.


A Gray-Code Type Bit Assignment Algorithm For Unitary Space-Time Constellations, Adam Panagos, Kurt Louis Kosbar Nov 2007

A Gray-Code Type Bit Assignment Algorithm For Unitary Space-Time Constellations, Adam Panagos, Kurt Louis Kosbar

Electrical and Computer Engineering Faculty Research & Creative Works

Many techniques for constructing unitary space- time constellations have been proposed. To minimize bit-error rate (BER) in a wireless communication system, constellations constructed using these techniques should be given a Gray- code type bit assignment, where symbols which are close in signal space have bit assignments which have small Hamming distance. To the authors' knowledge, no efficient general strategy for making this bit assignment has been suggested. This work proposes a prioritized distance (PD) algorithm for making this assignment in an optimal manner by minimizing the probability of bit error union bound. The algorithm can be used on constellations constructed …


Comparative Application Of Differential Evolution And Particle Swarm Techniques To Reactive Power And Voltage Control, G. A. Bakare, G. Krost, Ganesh K. Venayagamoorthy, U. O. Aliyu Nov 2007

Comparative Application Of Differential Evolution And Particle Swarm Techniques To Reactive Power And Voltage Control, G. A. Bakare, G. Krost, Ganesh K. Venayagamoorthy, U. O. Aliyu

Electrical and Computer Engineering Faculty Research & Creative Works

This paper presents the comparative application of two metaheuristic approaches: Differential Evolution (DE) and Particle Swarm Optimization (PSO) to the solution of the reactive power and voltage control problem. Efficient distribution of reactive power in an electric network leads to minimization of the system losses and improvement of the system voltage profile. It can be achieved by varying the excitation of generators or the on-load tap changer positions of transformers as well as by switching of discrete portions of inductors or capacitors etc. This constitutes a typical mixed integer non-linear optimization problem for the solution of which metaheuristic techniques have …


Estimation Of High-Frequency Currents From Near-Field Scan Measurements, Haixiao Weng, Daryl G. Beetner, Richard E. Dubroff, Jin Shi Nov 2007

Estimation Of High-Frequency Currents From Near-Field Scan Measurements, Haixiao Weng, Daryl G. Beetner, Richard E. Dubroff, Jin Shi

Electrical and Computer Engineering Faculty Research & Creative Works

High-frequency currents on the pins of integrated circuits (ICs) and on printed circuit board (PCB) traces are needed to predict and analyze electromagnetic interference in high-speed devices. These currents can, however, be difficult to measure when traces are buried within the PCB or chip-package, especially when several current-carrying traces are in close proximity. Techniques for estimating high-frequency currents from near-field scan data are proposed in this paper. These techniques are applied to find currents on the pins of an IC, on traces buried beneath other traces in a PCB, and on traces over a slot in the ground plane. Methods …


Modeling Noise Coupling Between Package And Pcb Power/Ground Planes With An Efficient 2-D Fdtd/Lumped Element Method, Ting-Kuang Wang, Sin-Ting Chen, Chi-Wei Tsai, Sung-Mao Wu, James L. Drewniak, Tzong-Lin Wu Nov 2007

Modeling Noise Coupling Between Package And Pcb Power/Ground Planes With An Efficient 2-D Fdtd/Lumped Element Method, Ting-Kuang Wang, Sin-Ting Chen, Chi-Wei Tsai, Sung-Mao Wu, James L. Drewniak, Tzong-Lin Wu

Electrical and Computer Engineering Faculty Research & Creative Works

An efficient numerical approach based on the 2-D finite-difference time-domain (FDTD) method is proposed to model the power/ground plane noise or simultaneously switching noise (SSN), including the interconnect effect between the package and the print circuit board (PCB). The space between the power and ground planes on the package and PCB are meshed with 2-D cells. The equivalent R-L-C circuits of the via and the solder balls connecting the package and PCB can be incorporated into a 2-D Yee cell based on a novel integral formulation in the time domain. An efficient recursive updating algorithm is proposed to fit the …


Predictive Congestion Control Protocol For Wireless Sensor Networks, Maciej Jan Zawodniok, Jagannathan Sarangapani Nov 2007

Predictive Congestion Control Protocol For Wireless Sensor Networks, Maciej Jan Zawodniok, Jagannathan Sarangapani

Electrical and Computer Engineering Faculty Research & Creative Works

Available congestion control schemes, for example transport control protocol (TCP), when applied to wireless networks, result in a large number of packet drops, unfair scenarios and low throughputs with a significant amount of wasted energy due to retransmissions. To fully utilize the hop by hop feedback information, this paper presents a novel, decentralized, predictive congestion control (DPCC) for wireless sensor networks (WSN). The DPCC consists of an adaptive flow and adaptive back-off interval selection schemes that work in concert with energy efficient, distributed power control (DPC). The DPCC detects the onset of congestion using queue utilization and the embedded channel …


Optimal Control Of Class Of Non-Linear Plants Using Artificial Immune Systems: Application Of The Clonal Selection Algorithm, S. A. Panimadai Ramaswamy, Ganesh K. Venayagamoorthy, S. N. Balakrishnan Oct 2007

Optimal Control Of Class Of Non-Linear Plants Using Artificial Immune Systems: Application Of The Clonal Selection Algorithm, S. A. Panimadai Ramaswamy, Ganesh K. Venayagamoorthy, S. N. Balakrishnan

Electrical and Computer Engineering Faculty Research & Creative Works

The function of natural immune system is to protect the living organisms against invaders/pathogens. Artificial Immune System (AIS) is a computational intelligence paradigm inspired by the natural immune system. Diverse engineering problems have been solved in the recent past using AIS. Clonal selection is one of the few algorithms that belong to the family of AIS techniques. Clonal selection algorithm is the computational implementation of the clonal selection principle. The process of affinity maturation of the immune system is explicitly incorporated in this algorithm. This paper presents the application of AIS for the optimal control of a class of non-linear …


Comparisons Of An Adaptive Neural Network Based Controller And An Optimized Conventional Power System Stabilizer, Wenxin Liu, Ganesh K. Venayagamoorthy, Jagannathan Sarangapani, Donald C. Wunsch, Mariesa Crow, Li Liu, David A. Cartes Oct 2007

Comparisons Of An Adaptive Neural Network Based Controller And An Optimized Conventional Power System Stabilizer, Wenxin Liu, Ganesh K. Venayagamoorthy, Jagannathan Sarangapani, Donald C. Wunsch, Mariesa Crow, Li Liu, David A. Cartes

Electrical and Computer Engineering Faculty Research & Creative Works

Power system stabilizers are widely used to damp out the low frequency oscillations in power systems. In power system control literature, there is a lack of stability analysis for proposed controller designs. This paper proposes a Neural Network (NN) based stabilizing controller design based on a sixth order single machine infinite bus power system model. The NN is used to compensate the complex nonlinear dynamics of power system. To speed up the learning process, an adaptive signal is introduced to the NN's weights updating rule. The NN can be directly used online without offline training process. Magnitude constraint of the …


Hydrological Monitoring With Hybrid Sensor Networks, Thomas V. Freiberger, Sahra Sedigh, Estella A. Atekwana Oct 2007

Hydrological Monitoring With Hybrid Sensor Networks, Thomas V. Freiberger, Sahra Sedigh, Estella A. Atekwana

Electrical and Computer Engineering Faculty Research & Creative Works

Existing hydrological monitoring systems suffer from short- comings in accuracy, resolution, and scalability. Their fragility, high power consumption, and lack of autonomy necessitate frequent site visits. Cabling requirements and large size limit their scalability and make them prohibitively expensive. The research described in this paper proposes to alleviate these problems by pairing high-resolution in situ measure- ment with remote data collection and software maintenance. A hybrid sensor network composed of wired and wireless connections autonomously measures various attributes of the soil, including moisture, temperature, and resistivity. The mea- surements are communicated to a processing server over the existing GSM cellular …


Neural Network Based Decentralized Controls Of Large Scale Power Systems, Wenxin Liu, Jagannathan Sarangapani, Ganesh K. Venayagamoorthy, Donald C. Wunsch, Mariesa Crow, Li Liu, David A. Cartes Oct 2007

Neural Network Based Decentralized Controls Of Large Scale Power Systems, Wenxin Liu, Jagannathan Sarangapani, Ganesh K. Venayagamoorthy, Donald C. Wunsch, Mariesa Crow, Li Liu, David A. Cartes

Electrical and Computer Engineering Faculty Research & Creative Works

This paper presents a suite of neural network (NN) based decentralized controller designs for large scale power systems' generators, one is for the excitation control and the other is for the steam valve control. Though the control inputs are calculated using local signals, the transient and overall system stability can be guaranteed. NNs are used to approximate the unknown and/or imprecise dynamics of the local power system dynamics and the inter-connection terms, thus the requirements for exact system parameters are relaxed. Simulation studies with a three-machine power system demonstrate the effectiveness of the proposed controller designs.


Discussion On Effective Control Of Inter-Area Oscillations By Upfcs, Mahyar Zarghami, Mariesa Crow Oct 2007

Discussion On Effective Control Of Inter-Area Oscillations By Upfcs, Mahyar Zarghami, Mariesa Crow

Electrical and Computer Engineering Faculty Research & Creative Works

The paper discusses an effective method for damping inter-area oscillations in a power network using UPFCs. This two stage method controls voltage magnitudes/angles of the two sides of the UPFC based on a linearized approach, which in turn will command modulation amplitudes and angles of the UPFC. The method is compared to a one stage linearized approach which directly commands modulation amplitudes and angles of the UPFC. Discussion on the feasibility of the method and its relation to the steady-state operation of the UPFC is also addressed.


A Survey Of Neural Computation On Graphics Processing Hardware, Ryan J. Meuth, Donald C. Wunsch Oct 2007

A Survey Of Neural Computation On Graphics Processing Hardware, Ryan J. Meuth, Donald C. Wunsch

Electrical and Computer Engineering Faculty Research & Creative Works

Modern graphics processing units (GPU) are used for much more than simply 3D graphics applications. From machine vision to finite element analysis, CPU's are being used in diverse applications, collectively called general purpose graphics processor utilization. This paper explores the capabilities and limitations of modern GPU's and surveys the neural computation technologies that have been applied to these devices.


Energy-Efficient Hybrid Key Management Protocol For Wireless Sensor Networks, Timothy J. Landstra, Maciej Jan Zawodniok, Jagannathan Sarangapani Oct 2007

Energy-Efficient Hybrid Key Management Protocol For Wireless Sensor Networks, Timothy J. Landstra, Maciej Jan Zawodniok, Jagannathan Sarangapani

Electrical and Computer Engineering Faculty Research & Creative Works

In this paper, we propose a subnetwork key management strategy in which the heterogeneous security requirements of a wireless sensor network are considered to provide differing levels of security with minimum communication overhead. Additionally, it allows the dynamic creation of high security subnetworks within the wireless sensor network and provides subnetworks with a mechanism for dynamically creating a secure key using a novel and dynamic group key management protocol. The proposed energy-efficient protocol utilizes a combination of pre-deployed group keys and initial trustworthiness of nodes to create a level of trust between neighbors in the network. This trust is later …


Control Of Nonholonomic Mobile Robot Formations Using Neural Networks, Jagannathan Sarangapani, Travis Alan Dierks Oct 2007

Control Of Nonholonomic Mobile Robot Formations Using Neural Networks, Jagannathan Sarangapani, Travis Alan Dierks

Electrical and Computer Engineering Faculty Research & Creative Works

In this paper the control of formations of multiple nonholonomic mobile robots is attempted by integrating a kinematic controller with a neural network (NN) computed-torque controller. A combined kinematic/torque control law is developed for leader-follower based formation control using backstepping in order to accommodate the dynamics of the robots and the formation in contrast with kinematic-based formation controllers. The NN is introduced to approximate the dynamics of the follower as well as its leader using online weight tuning. It is shown using Lyapunov theory that the errors for the entire formation are uniformly ultimately bounded, and numerical results are provided.


Development Of A Facts Real-Time Hardware-In-The-Loop Simulation, Keyou Wang, Ying Cheng, Mariesa Crow Oct 2007

Development Of A Facts Real-Time Hardware-In-The-Loop Simulation, Keyou Wang, Ying Cheng, Mariesa Crow

Electrical and Computer Engineering Faculty Research & Creative Works

This paper describes an approach to simulate the bulk power transmission system using hardware-in-the-loop (HIL) FACTS devices. The architecture of the HIL simulation is described and a DSP-PC-based UPFC device designed for HIL simulation is presented. The implementation of UPFC hardware, software and basic control are discussed. Experimental results are provided to support the proposed concept.


Dft Techniques And Automation For Asynchronous Null Conventional Logic Circuits, Venkat Satagopan, Waleed K. Al-Assadi, Scott C. Smith, Sindhu Kakarla, Bonita Bhaskaran Oct 2007

Dft Techniques And Automation For Asynchronous Null Conventional Logic Circuits, Venkat Satagopan, Waleed K. Al-Assadi, Scott C. Smith, Sindhu Kakarla, Bonita Bhaskaran

Electrical and Computer Engineering Faculty Research & Creative Works

Conventional automatic test pattern generation (ATPG) algorithms fail when applied to asynchronous NULL convention logic (NCL) circuits due to the absence of a global clock and presence of more state-holding elements, leading to poor fault coverage. This paper presents a design-for-test (DFT) approach aimed at making asynchronous NCL designs testable using conventional ATPG programs. We propose an automatic DFT insertion flow (ADIF) methodology that performs scan and test point insertion on NCL designs to improve test coverage, using a custom ATPG library. Experimental results show significant increase in fault coverage for NCL cyclic and acyclic pipelined designs.


Work In Progress -- Tailoring Optics Resources For K-5 Pre-College Outreach, Theresa M. Swift, Steve Eugene Watkins Oct 2007

Work In Progress -- Tailoring Optics Resources For K-5 Pre-College Outreach, Theresa M. Swift, Steve Eugene Watkins

Electrical and Computer Engineering Faculty Research & Creative Works

Pre-college instruction in science, technology, Engineering; and mathematics (STEM) is critical to preparing a workforce and citizens for a technology-based society. The K-5 years are especially important to creating interest and instilling basic concepts. Engineering-based pre-college outreach can provide useful resources in the K- 5 education classroom. However, interaction among K-5 teachers and STEM professionals is more effective if outreach is tailored to the K-5 environment. In particular, resources and outreach should accommodate K-5 assessment standards, level-appropriate concept definition, and grade continuity. This work uses a set of optics resources as an example of tailored outreach. Example lessons and activities …


Cascading Line Outage Prevention With Multiple Upfcs, Hong Tao Ma, Mariesa Crow, Badrul H. Chowdhury, Adam Lininger Oct 2007

Cascading Line Outage Prevention With Multiple Upfcs, Hong Tao Ma, Mariesa Crow, Badrul H. Chowdhury, Adam Lininger

Electrical and Computer Engineering Faculty Research & Creative Works

Flexible AC Transmission System (FACTS) have been recognized to be effective in regulating network power flow and enhance system dynamic performance. In this paper, multiple UPFCs are integrated into a network and controlled according to the Max Flow algorithm to avoid possible cascading line outage. The dynamic response of UPFC controllers and generator performance are investigated with potential cascading critical line outage. Cascading blackout prevention is investigated not only for steady state power flow overload problem but also for system dynamic stability problem. Generator performances of speed deviation, angle deviations and bus voltage profile as well as dynamic power flows …


Inference Of Genetic Regulatory Networks With Recurrent Neural Network Models Using Particle Swarm Optimization, Rui Xu, Donald C. Wunsch, Ronald L. Frank Oct 2007

Inference Of Genetic Regulatory Networks With Recurrent Neural Network Models Using Particle Swarm Optimization, Rui Xu, Donald C. Wunsch, Ronald L. Frank

Electrical and Computer Engineering Faculty Research & Creative Works

Genetic regulatory network inference is critically important for revealing fundamental cellular processes, investigating gene functions, and understanding their relations. The availability of time series gene expression data makes it possible to investigate the gene activities of whole genomes, rather than those of only a pair of genes or among several genes. However, current computational methods do not sufficiently consider the temporal behavior of this type of data and lack the capability to capture the complex nonlinear system dynamics. We propose a recurrent neural network (RNN) and particle swarm optimization (PSO) approach to infer genetic regulatory networks from time series gene …


Blueprint For Iteratively Hardening Power Grids Employing Unified Power Flow Controllers, William M. Siever, Ann K. Miller, Daniel R. Tauritz Sep 2007

Blueprint For Iteratively Hardening Power Grids Employing Unified Power Flow Controllers, William M. Siever, Ann K. Miller, Daniel R. Tauritz

Electrical and Computer Engineering Faculty Research & Creative Works

A stable electricity supply is vital for modern society. However, many parts of our power transmission grid are operating near their operational limits. Such stressed systems are vulnerable to cascading failures, where a few small faults can induce a cascade of failures potentially leading to a major blackout The unified power flow controller (UPFC), the most powerful highspeed, semi-conductor based power flow device, can be used as a theoretical model to study how these devices can be used to improve power grid resilience. The blueprint presented here can be used to iteratively identify critical weaknesses in power grids and to …


Robust Tuning Of Modern Power System Stabilizers Using Bacterial Foraging Algorithm, B. Sumanbabu, S. Mishra, B. K. Panigrahi, Ganesh K. Venayagamoorthy Sep 2007

Robust Tuning Of Modern Power System Stabilizers Using Bacterial Foraging Algorithm, B. Sumanbabu, S. Mishra, B. K. Panigrahi, Ganesh K. Venayagamoorthy

Electrical and Computer Engineering Faculty Research & Creative Works

IEEE Std 421.5, revised by the IEEE excitation system subcommittee introduced a new type of power system stabilizer model, the multiband power system stabilizers (IEEE PSS4B). Although it requires two input signals, like the widely used IEEE PSS2B, the underlying principle of the new IEEE PSS4B makes it sharply different. This paper presents a method based on Bacterial Foraging Algorithm (BFA) to simultaneously tune these modern power system stabilizers (PSSs) in multimachine power system. Simulation results of multi-machine power system validate the efficiency of this approach. the proposed method is effective for the tuning of multi-controllers in large power systems.


Development And Laboratory Trials Of The Light-Based High-Resolution Target Movement Monitor For Monitoring Convergence At Underground Mines, B. D. Apel, B. R. Gray, Randy Hays Moss, Steve Eugene Watkins, T. H. Jones Sep 2007

Development And Laboratory Trials Of The Light-Based High-Resolution Target Movement Monitor For Monitoring Convergence At Underground Mines, B. D. Apel, B. R. Gray, Randy Hays Moss, Steve Eugene Watkins, T. H. Jones

Electrical and Computer Engineering Faculty Research & Creative Works

This paper describes a development and laboratory evaluation of the light-based high-resolution target movement monitor which can be used to measure convergence at underground excavations with submillimeter accuracy. The monitor is based on unique measurement technology which was developed at the University of Missouri-Rolla. This system has the potential for high accuracy detection and monitoring of positional changes (as small as 0.1mm with the current laboratory implementation) presented by many types of targets located in close proximity to or at far distances from the monitor. The sensitivity of the system to camera resolution and the error analysis as a function …


Plug-In Hybrid Vehicles -- A Vision For The Future, Mehdi Ferdowsi Sep 2007

Plug-In Hybrid Vehicles -- A Vision For The Future, Mehdi Ferdowsi

Electrical and Computer Engineering Faculty Research & Creative Works

One of the unique advantages of plug-in hybrid vehicles is their capability to integrate the transportation and electric power generation sectors in order to improve the efficiency, fuel economy, and reliability of both systems. This goal is performed via integration of the onboard energy storage units of plug-in vehicles with the power grid by power electronic converters and communication systems. Employing energy storage systems improves the efficiency and reliability of the electric power generation, transmission, and distribution. Similarly, combining an energy storage system with the power train of a conventional vehicle results in a hybrid vehicle with higher fuel efficiency. …


Defect-Tolerant Gate Macro Mapping & Placement In Clock-Free Nanowire Crossbar Architecture, Ravi Bonam, Yong-Bin Kim, Minsu Choi Sep 2007

Defect-Tolerant Gate Macro Mapping & Placement In Clock-Free Nanowire Crossbar Architecture, Ravi Bonam, Yong-Bin Kim, Minsu Choi

Electrical and Computer Engineering Faculty Research & Creative Works

Recently, we proposed a new clock-free nanowire crossbar architecture based on a delayinsensitive paradigm called Null Convention Logic (NCL). The proposed architecture has simple periodic structure that is suitable for non-deterministic nanoscale assembly and does not require a clock distribution network - so it is intrinsically free from timing-related failure modes. Even though the proposed architecture offers improved manufacturability, it is still not free from defects. This paper elaborates on the different programming techniques to map a given threshold gate macro on a random PGMB (Programmable Gate Macro Block) with predefined dimension. Defect-Aware and Defect Unaware approaches have been considered …


Increased Performance Of Battery Packs By Active Equalization, Jonathan W. Kimball, Brian T. Kuhn, Philip T. Krein Sep 2007

Increased Performance Of Battery Packs By Active Equalization, Jonathan W. Kimball, Brian T. Kuhn, Philip T. Krein

Electrical and Computer Engineering Faculty Research & Creative Works

Battery packs for most applications are series strings of electrochemical cells. Due to manufacturing variations, temperature differences, and aging, the individual cells perform differently. When a complete pack is charged and discharged as a single two-terminal circuit element, some cells are chronically overcharged, undercharged, or overdischarged, all of which act to reduce cell life. The performance and life of the complete pack is limited by the weakest cell. Many methods have been proposed and explored to mitigate this problem. In the present work, a switched-capacitor converter is shown to be a simple and effective method to maintain equal cell or …


Self-Healing Control With Multifunctional Gate Drive Circuits For Power Converters, Peng Xiao, Ganesh K. Venayagamoorthy, Keith Corzine, Robert S. Woodley Sep 2007

Self-Healing Control With Multifunctional Gate Drive Circuits For Power Converters, Peng Xiao, Ganesh K. Venayagamoorthy, Keith Corzine, Robert S. Woodley

Electrical and Computer Engineering Faculty Research & Creative Works

Many commercial and military transport systems have fault diagnostic functions implemented to help protect the device when a severe fault occurs. However, most present systems do not contain prognostics capability which would allow operators to observe an unhealthy system component in its pre- fault condition. In industry applications, scheduled downtime can result in considerable cost avoidance. The next technology step is self-healing system components which observe not only potential problems, but can also take steps to continue operation under abnormal conditions - whether due to long-term normal wear-and-tear or sudden combat damage. In this paper, current and voltage information using …