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Weak-Group Unitary Space-Time Codes, Adam Panagos, Kurt Louis Kosbar, Asif Iqbal Mohammad Nov 2006

Weak-Group Unitary Space-Time Codes, Adam Panagos, Kurt Louis Kosbar, Asif Iqbal Mohammad

Electrical and Computer Engineering Faculty Research & Creative Works

We propose a construction technique for unitary space-time codes that use Givens rotation matrices. These constellations have a desirable weak group property that leads to reduced construction and decoding complexity. The newly constructed constellations have the best known diversity product and diversity sum for a wide range of constellation sizes and number of transmit antennas.


Synchronous Reference Frame Based Active Filter Current Reference Generation Using Neural Networks, Joy Mazumdar, Ronald G. Harley, Ganesh K. Venayagamoorthy Nov 2006

Synchronous Reference Frame Based Active Filter Current Reference Generation Using Neural Networks, Joy Mazumdar, Ronald G. Harley, Ganesh K. Venayagamoorthy

Electrical and Computer Engineering Faculty Research & Creative Works

The increased use of nonlinear devices in industry has resulted in direct increase of harmonic distortion in the industrial power system in recent years. The significant harmonics are almost always 5th, 7th, 11th and the 13th with the 5th harmonic being the largest in most instances. Active filter systems have been proposed to mitigate harmonic currents of the industrial loads. The most important requirement for any active filter is the precise detection of the individual harmonic component's amplitude and phase. Fourier transform based techniques provide an excellent method for individual harmonic isolation, but it requires a minimum of two ...


A Novel Seven-Level Shunt Active Filter For High-Power Drive Systems, Xiao Peng, Keith Corzine, Ganesh K. Venayagamoorthy Nov 2006

A Novel Seven-Level Shunt Active Filter For High-Power Drive Systems, Xiao Peng, Keith Corzine, Ganesh K. Venayagamoorthy

Electrical and Computer Engineering Faculty Research & Creative Works

In high-power adjustable speed motor drives, such as those used in electric ship propulsion systems, active filters provide a viable solution to mitigating harmonic related issues caused by diode or thyristor rectifier front-ends. To handle the large compensation currents and provide better thermal management, two or more paralleled semiconductor switching devices are often used. In this paper, a novel topology is proposed where two active filter inverters are connected with tapped reactors to share the compensation currents. The proposed active filter topology can also produce seven voltage levels, which significantly reduces the switching current ripple and the size of ripple ...


Cancellation Predictive Control For Three-Phase Pwm Rectifiers Under Harmonic And Unbalanced Input Conditions, Peng Xiao, Keith Corzine, Ganesh K. Venayagamoorthy Nov 2006

Cancellation Predictive Control For Three-Phase Pwm Rectifiers Under Harmonic And Unbalanced Input Conditions, Peng Xiao, Keith Corzine, Ganesh K. Venayagamoorthy

Electrical and Computer Engineering Faculty Research & Creative Works

This paper presents an intuitive and simple-to-implement control scheme to improve the performance of three-phase boost-type PWM rectifiers under harmonic and unbalanced input conditions. Unlike most other control strategies, the proposed method does not need to extract either the harmonic or the negative-sequence components in the supply voltages and currents. A near-synchronous reference frame is used to determine the positive-sequence fundamental-frequency component in the input voltages. Utilizing only the extracted component, the DC-link voltage control and power factor control are implemented independently to determine the phase angle and magnitude of the PWM reference voltage. The commanded rectifier voltage adjustments are ...


Optimal Placement And Control Of Unified Power Flow Control Devices Using Evolutionary Computing And Sequential Quadratic Programming, Radha P. Kalyani, Mariesa Crow, Daniel R. Tauritz Nov 2006

Optimal Placement And Control Of Unified Power Flow Control Devices Using Evolutionary Computing And Sequential Quadratic Programming, Radha P. Kalyani, Mariesa Crow, Daniel R. Tauritz

Electrical and Computer Engineering Faculty Research & Creative Works

A crucial factor effecting modern power systems today is power flow control. An effective means for controlling and improving power flow is by installing fast reacting devices such as a unified power flow controller (UPFC). For maximum positive impact of this device on the power grid, it should be installed at an optimal location and employ an optimal realtime control algorithm. This paper proposes the combination of an evolutionary algorithm (EA) to find the optimal location and sequential quadratic programming (SQP) to optimize the UPFC control settings. Simulations are conducted using the classic IEEE 118 bus test system. For comparison ...


Detection And Identification Of Vehicles Based On Their Unintended Electromagnetic Emissions, Xiaopeng Dong, Haixiao Weng, Daryl G. Beetner, Todd H. Hubing, Donald C. Wunsch, Michael Noll, Huseyin Goksu, Benjamin Moss Nov 2006

Detection And Identification Of Vehicles Based On Their Unintended Electromagnetic Emissions, Xiaopeng Dong, Haixiao Weng, Daryl G. Beetner, Todd H. Hubing, Donald C. Wunsch, Michael Noll, Huseyin Goksu, Benjamin Moss

Electrical and Computer Engineering Faculty Research & Creative Works

When running, vehicles with internal combustion engines radiate electromagnetic emissions that are characteristic of the vehicle. Emissions depend on the electronics, harness wiring, body type, and many other features. Since emissions are unique to each vehicle, these may be used for identification purposes. This paper investigates a procedure for detecting and identifying vehicles based on their RF emissions. Parameters like the average magnitude or standard deviation of magnitude within a frequency band were extracted from measured emission data. These parameters were used as inputs to an artificial neural network (ANN) that was trained to identify the vehicle that produced the ...


Dynamic Programming-Based Energy-Efficient Rate Adaptation For Wireless Ad Hoc Networks, Maciej Jan Zawodniok, Jagannathan Sarangapani Nov 2006

Dynamic Programming-Based Energy-Efficient Rate Adaptation For Wireless Ad Hoc Networks, Maciej Jan Zawodniok, Jagannathan Sarangapani

Electrical and Computer Engineering Faculty Research & Creative Works

Resource constraints require that ad hoc wireless networks are energy efficient during transmission and rate adaptation. In this paper we propose a novel cross-layer energy-efficient rate adaptation scheme that employs dynamic programming (DP) principle to analytically select the modulation scheme online. The scheme uses channel state information from the physical layer and congestion information from the scheduling layer to select a modulation rate. This online selection maximizes throughput while saving energy and preventing congestion. The simulation results indicate that an increase in throughput by 96% and energy-efficiency by 131% is observed when compared to the Receiver Based AutoRate (RBAR) protocol.


Adaptive Critic Neural Network Force Controller For Atomic Force Microscope-Based Nanomanipulation, Qinmin Yang, Jagannathan Sarangapani Oct 2006

Adaptive Critic Neural Network Force Controller For Atomic Force Microscope-Based Nanomanipulation, Qinmin Yang, Jagannathan Sarangapani

Electrical and Computer Engineering Faculty Research & Creative Works

Automating the task of nanomanipulation is extremely important since it is tedious for humans. This paper proposes an atomic force microscope (AFM) based force controller to push nano particles on the substrates. A block phase correlation-based algorithm is embedded into the controller for the compensation of the thermal drift which is considered as the main external uncertainty during nanomanipulation. Then, the interactive forces and dynamics between the tip and the particle, particle and the substrate are modeled and analyzed. Further, an adaptive critic NN controller based on adaptive dynamic programming algorithm is designed and the task of pushing nano particles ...


An Unique Ultracapacitor Direct Integration Scheme In Multilevel Motor Drives For Large Vehicle Propulsion, Shuai Lu, Keith Corzine, Mehdi Ferdowsi Oct 2006

An Unique Ultracapacitor Direct Integration Scheme In Multilevel Motor Drives For Large Vehicle Propulsion, Shuai Lu, Keith Corzine, Mehdi Ferdowsi

Electrical and Computer Engineering Faculty Research & Creative Works

This paper introduces a new set of methods to directly integrate ultracapacitor banks into cascaded multilevel inverters used for large vehicle propulsion. The idea is to replace the regular dc-link capacitors with ultracapacitors in order to combine the energy storage unit and motor drive. This approach eliminates the need for an interfacing dc-dc converter and considerably improves the efficiency of regenerative braking energy restoration in electric and hybrid vehicles. Utilizing the proposed modulation control set, the two cascaded inverters can have their dc voltage levels maintained at any ratio (even a noninteger ratio) or dynamically varied over a wide range ...


Ac Impedance Measurement By Line-To-Line Injected Current, Keith Corzine, Jing Huang Oct 2006

Ac Impedance Measurement By Line-To-Line Injected Current, Keith Corzine, Jing Huang

Electrical and Computer Engineering Faculty Research & Creative Works

Naval ship as well as aerospace power systems are incorporating a greater degree of power electronic switching sources and loads. Although these components provide exceptional performance, they are prone to instability due to their high efficiency and constant power characteristics which lead to a negative impedance nature. When designing these systems, system integrators must consider the impedance versus frequency at an interface (which designates source and load). Stability criteria have been developed in terms of source and load impedance for both DC and AC systems and it is often helpful to have techniques for impedance measurement. For DC systems, the ...


High Efficiency Energy Storage System Design For Hybrid Electric Vehicle With Motor Drive Integration, Shuai Lu, Keith Corzine, Mehdi Ferdowsi Oct 2006

High Efficiency Energy Storage System Design For Hybrid Electric Vehicle With Motor Drive Integration, Shuai Lu, Keith Corzine, Mehdi Ferdowsi

Electrical and Computer Engineering Faculty Research & Creative Works

This paper proposes a new energy storage system (ESS) design including both batteries and ultracapacitors (UC) in hybrid electric vehicle (HEV) and electric vehicle (EV) applications. The conventional designs require a dc-dc converter to interface the UC unit. Herein, the UC can be directly switched across the motor drive dc-link during the peak power demands. The resulting wide voltage variation due to UC power transfer is addressed by the simple modulator introduced in this paper, so that the motor drive performance is not disrupted. Based on this new methodology, the paper further introduces two ESS schemes with different topologies, UC ...


Inherited Redundancy And Configurability Utilization For Repairing Nanowire Crossbars With Clustered Defects, Yadunandana Yellambalase, Minsu Choi, Yong-Bin Kim Oct 2006

Inherited Redundancy And Configurability Utilization For Repairing Nanowire Crossbars With Clustered Defects, Yadunandana Yellambalase, Minsu Choi, Yong-Bin Kim

Electrical and Computer Engineering Faculty Research & Creative Works

With the recent development of nanoscale materials and assembly techniques, it is envisioned to build high-density reconfigurable systems which have never been achieved by the photolithography. Various reconfigurable architectures have been proposed based on nanowire crossbar structure as the primitive building block. Unfortunately, high-density systems consisting of nanometer-scale elements are likely to have many imperfections and variations; thus, defect-tolerance is considered as one of the most exigent challenges. In this paper, we evaluate three different logic mapping algorithms with defect avoidance to circumvent clustered defective crosspoints in nanowire reconfigurable crossbar architectures. The effectiveness of inherited redundancy and configurability utilization is ...


Intelligent Integration Of A Wind Farm To An Utility Power Network With Improved Voltage Stability, V. K. Polisetty, Sandhya R. Jetti, Ganesh K. Venayagamoorthy, Ronald G. Harley Oct 2006

Intelligent Integration Of A Wind Farm To An Utility Power Network With Improved Voltage Stability, V. K. Polisetty, Sandhya R. Jetti, Ganesh K. Venayagamoorthy, Ronald G. Harley

Electrical and Computer Engineering Faculty Research & Creative Works

The increasing effect of wind energy generation will influence the dynamic behavior of power systems by interacting with conventional generation and loads. Due to the inherent characteristics of wind turbines, non-uniform power production causes variations in system voltage and frequency. Therefore, a wind farm requires high reactive power compensation. Flexible AC transmission systems (FACTS) devices such as SVCs inject reactive power into the system which helps in maintaining a better voltage profile. This paper presents the design of a linear and a nonlinear coordinating controller between a SVC and the wind farm inverter at the point of interconnection. The performances ...


Real-Time Implementation Of A Dual Function Neuron Based Wide Area Svc Damping Controller, Sandhya R. Jetti, Ganesh K. Venayagamoorthy Oct 2006

Real-Time Implementation Of A Dual Function Neuron Based Wide Area Svc Damping Controller, Sandhya R. Jetti, Ganesh K. Venayagamoorthy

Electrical and Computer Engineering Faculty Research & Creative Works

The use of wide area measurements for power system stabilization is recently given a lot of attention by researchers and the power industry to avoid cascading failures and blackouts such as the August 2003. This paper presents the design of a nonlinear external damping controller based on wide area measurements as inputs to a dual function neuron (DFN). This DFN controller is specifically designed to enhance the damping characteristics of a power system considering the nonlinearity in the system. The major advantage of the DFN controller is that it is simple in structure with less development time and hardware requirements ...


Bio-Inspired Algorithms For The Design Of Multiple Optimal Power System Stabilizers: Sppso And Bfa, Tridib Kumar Das, Ganesh K. Venayagamoorthy Oct 2006

Bio-Inspired Algorithms For The Design Of Multiple Optimal Power System Stabilizers: Sppso And Bfa, Tridib Kumar Das, Ganesh K. Venayagamoorthy

Electrical and Computer Engineering Faculty Research & Creative Works

Power System Stabilizers (PSSs) provide stabilizing control signals to excitation systems to damp out inter-area and intra-area oscillations. The PSS must be optimally tuned to accommodate the variations in the system dynamics. Designing multiple optimal PSSs is a challenging task for researchers. This paper presents the comparison between two bio-inspired algorithms: a Small Population based Particle Swarm Optimization (SPPSO) and the Bacterial Foraging Algorithm (BFA) for the simultaneous tuning of a number of PSSs in a multi-machine power system. The cost function to be optimized by both algorithms takes into consideration the time domain transient responses. The effectiveness of the ...


Efficient And Robust Delay-Insensitive Qca (Quantum-Dot Cellular Automata) Design, Minsu Choi, Myungsu Choi, Zachary D. Patitz, Nohpill Park Oct 2006

Efficient And Robust Delay-Insensitive Qca (Quantum-Dot Cellular Automata) Design, Minsu Choi, Myungsu Choi, Zachary D. Patitz, Nohpill Park

Electrical and Computer Engineering Faculty Research & Creative Works

The concept of clocking for QCA, referred to as the four-phase clocking, is widely used. However, inherited characteristics of QCA, such as the way to hold state, the way to synchronize data flows, and the way to power QCA cells, make the design of QCA circuits quite different from VLSI and introduce a variety of new design challenges. The most severe challenges are due to the fact that the overall timing of a QCA circuit is mainly dependent upon its layout. This issue is commonly referred to as the "layout =timing" problem. To circumvent the problem, a novel self-timed circuit ...


Nonlinear Modified Pi Control Of Multi-Module Gcscs In A Large Power System, Swakshar Ray, Ganesh K. Venayagamoorthy Oct 2006

Nonlinear Modified Pi Control Of Multi-Module Gcscs In A Large Power System, Swakshar Ray, Ganesh K. Venayagamoorthy

Electrical and Computer Engineering Faculty Research & Creative Works

This paper presents the design of a new control strategy for gate-controlled series compensators (GCSCs). GCSCs are new FACTS devices which can provide active power flow control on a transmission line. Proper placement of GCSCs in proximity to generators can also provide damping to system oscillations. This paper has investigated the effectiveness of multiple multi-module gate controlled series compensators (MMGCSCs) for large power systems. MMGCSCs can be less expensive devices with wide range of control of capacitive reactance in series with transmission lines. A nonlinear modified PI (NMPI) control is developed to provide power flow control and enhanced transient stability ...


Large Scale Signal And Interconnect Fdtd Modeling For Bga Package, Xiaohe Chen, James L. Drewniak, Jianmin Zhang, Michael A. Cracraft, Bruce Archambeault, Samuel R. Connor Oct 2006

Large Scale Signal And Interconnect Fdtd Modeling For Bga Package, Xiaohe Chen, James L. Drewniak, Jianmin Zhang, Michael A. Cracraft, Bruce Archambeault, Samuel R. Connor

Electrical and Computer Engineering Faculty Research & Creative Works

This paper introduces a Finite-Difference Time-Domain (FDTD) approach to modeling portions of Ball Grid Array (BGA) package interconnect circuits. A fullwave circuit model including vias, trace segments, and ground vias was generated, using a computer gridding tool, and fed into the FDTD (Taflove and Hagness, 2005) program. The simulated results were correlated with TDR measurements.


Millimeter-Wave Differential Probe For Nondestructive Detection Of Corrosion Precursor Pitting, Mohammad Tayeb Ahmad Ghasr, Brian D. Carroll, Sergey Kharkovsky, Russell A. Austin, R. Zoughi Oct 2006

Millimeter-Wave Differential Probe For Nondestructive Detection Of Corrosion Precursor Pitting, Mohammad Tayeb Ahmad Ghasr, Brian D. Carroll, Sergey Kharkovsky, Russell A. Austin, R. Zoughi

Electrical and Computer Engineering Faculty Research & Creative Works

Critical aircraft structural components, such as wings and fuselages, are exposed to harsh environments that vary considerably in temperature and moisture content. In most cases, the corrosion is hidden under paint and primer and cannot be visually detected. The initiation of corrosion is preceded by the presence of corrosion precursor pitting. Near-field millimeter-wave nondestructive testing (NDT) methods have been successfully used for detecting corrosion precursor pitting in exposed as well as painted aluminum substrates. However, near-field millimeter-wave measurements are susceptible to clutter that may mask indications of small defects such as pitting. Standoff distance variation produces an unwanted intensity gradient ...


An Autonomous And Adaptable Wireless Device For Flood Monitoring, Valerio Plessi, Filippo Bastianini, Sahra Sedigh Sep 2006

An Autonomous And Adaptable Wireless Device For Flood Monitoring, Valerio Plessi, Filippo Bastianini, Sahra Sedigh

Electrical and Computer Engineering Faculty Research & Creative Works

Wireless devices can be used to monitor and record a broad range of phenomena. Their advantages include ease of installation and maintenance and considerable reduction in wiring costs. The addition of battery power and radio communication to such wireless devices can result in a completely The operating environment of monitoring systems is often hostile, due to temperature fluctuations, humidity, electromagnetic noise, and other interfering phenomena. The system should be able to adapt to changing conditions to maintain dependability in its operations This paper presents the case study of adapting a flood detection device to the environmental threat of submersion.


Trustworthy Computing Needs, Ann K. Miller Sep 2006

Trustworthy Computing Needs, Ann K. Miller

Electrical and Computer Engineering Faculty Research & Creative Works

The very label "critical infrastructure" implies that such systems are important. They are. Within the US alone, there are approximately 28,600 networked Federal Deposit Insurance Corporation (FDIC) institutions, 2 million miles of oil/gas pipelines, 2,800 power plants with 300,000 production sites, 104 nuclear power plants, 80,000 dams, 60,000 chemical plants, 87,000 food processing plants, and 1,600 water treatment plants. And, this is just part of our national infrastructure. Add to this telecommunications and other "everyday" utilities and the scope is enormous. Most of these systems, alone, would qualify as a network-centric system ...


Dynamic Maximum Power Point Tracking Of Photovoltaic Arrays Using Ripple Correlation Control, Trishan Esram, Jonathan W. Kimball, Philip T. Krein, Patrick L. Chapman, Pallab Midya Sep 2006

Dynamic Maximum Power Point Tracking Of Photovoltaic Arrays Using Ripple Correlation Control, Trishan Esram, Jonathan W. Kimball, Philip T. Krein, Patrick L. Chapman, Pallab Midya

Electrical and Computer Engineering Faculty Research & Creative Works

A dynamically rapid method used for tracking the maximum power point of photovoltaic arrays, known as ripple correlation control, is presented and verified against experiment. The technique takes advantage of the signal ripple, which is automatically present in power converters. The ripple is interpreted as a perturbation from which a gradient ascent optimization can be realized. The technique converges asymptotically at maximum speed to the maximum power point without the benefit of any array parameters or measurements. The technique has simple circuit implementations.


Analysis Of The Double-Tiered Three-Battery Switched Capacitor Battery Balancing System, Andrew Baughman, Mehdi Ferdowsi Sep 2006

Analysis Of The Double-Tiered Three-Battery Switched Capacitor Battery Balancing System, Andrew Baughman, Mehdi Ferdowsi

Electrical and Computer Engineering Faculty Research & Creative Works

The auto industry is progressing towards hybrid and fully electric vehicles in their future car models. These vehicles need a power plant that is reliable during the lifetime of the car. Battery and ultra-capacitor capacity imbalances stemming from manufacturing and ensuing driving environment and operational usage affect voltage levels, which must adhere to strict limits to ensure the safety of the driver. A double-tiered capacitive shuttling technique is applied to an idealized three-battery system simulation in order to balance the voltages. Parameters in the system are varied and their effects on the system determined. Results are compared to a single-tiered ...


The Effect Of Various Upfc Operating Points On Transient Stability, Mahyar Zarghami, Mariesa Crow Sep 2006

The Effect Of Various Upfc Operating Points On Transient Stability, Mahyar Zarghami, Mariesa Crow

Electrical and Computer Engineering Faculty Research & Creative Works

In this paper, it is shown that using the power injection model for a UPFC, there exists a set of operating points for which the same amount of AC bus voltage and active/reactive series power injections can be evaluated. These various operating points are designated by different dc bus voltages (Vdc) and modulation amplitudes (k1,k2) and phases (α12). Simulations show that the dynamic behavior of a UPFC could be related to its pre-fault operating situations. The question to be answered is to verify which operating point would be the best candidate from ...


Distributed Control Of Hybrid Motor Drives, Keith Corzine, Shuai Lu, T. H. Fikse Sep 2006

Distributed Control Of Hybrid Motor Drives, Keith Corzine, Shuai Lu, T. H. Fikse

Electrical and Computer Engineering Faculty Research & Creative Works

The hybrid inverter fed motor drive with two cascaded multilevel inverters is an attractive option for high performance high power applications such as naval ship propulsion systems due to a number of unique features. There is a natural split between a higher-voltage lower-frequency "bulk" inverter and a lower-voltage higher-frequency "conditioning" inverter in the cascaded system which matches the availability of semiconductor devices. Furthermore, the bulk inverter may be a commercial-off-the-shelf (COTS) motor drive meaning that only the conditioning inverter needs to be custom made. However, a drive involving a COTS bulk inverter would require a distributed conditioning inverter control which ...


New Double Input Dc-Dc Converters For Automotive Applications, Krishna P. Yalamanchili, Mehdi Ferdowsi, Keith Corzine Sep 2006

New Double Input Dc-Dc Converters For Automotive Applications, Krishna P. Yalamanchili, Mehdi Ferdowsi, Keith Corzine

Electrical and Computer Engineering Faculty Research & Creative Works

The energy storage unit is one of the most important subsystems in the structure of hybrid electric vehicles since it directly impacts the performance, fuel economy, cost, and weight of the vehicle. New structures for the energy storage unit, which utilize both batteries and ultracapacitors, are widely under investigation. In order to fully utilize the advantages of each energy storage device, employment of multi-input power converters is inevitable. In this paper, two new double input converters are introduced. Their different operating modes are analyzed and their voltage transfer ratios are derived. Simulation results are used to verify the expected operational ...


A General Purpose Framework For Wireless Sensor Network Applications, Ayman Z. Faza, Sahra Sedigh Sep 2006

A General Purpose Framework For Wireless Sensor Network Applications, Ayman Z. Faza, Sahra Sedigh

Electrical and Computer Engineering Faculty Research & Creative Works

Wireless sensor networks are becoming a basis for a rapidly increasing range of applications. Habitat, flood, and wildfire monitoring are interesting examples of such applications. Each application has different requirements in terms of node functionalities, network size, complexity and cost; therefore, it is worthwhile time investment to design and implement a general purpose framework for wireless sensor networks that would be adaptable to any monitoring application of interest with a minimum amount of effort. In this manuscript, we propose a basic structure for such a framework and highlight a number of challenges anticipated during the course of this doctoral research.


Engineering Of Ferrite-Graphite Composite Media For Microwave Shields, Marina Koledintseva, Poorna Chander Ravva, James L. Drewniak, Alexander A. Kitaytsev, Andrey A. Shinkov Aug 2006

Engineering Of Ferrite-Graphite Composite Media For Microwave Shields, Marina Koledintseva, Poorna Chander Ravva, James L. Drewniak, Alexander A. Kitaytsev, Andrey A. Shinkov

Electrical and Computer Engineering Faculty Research & Creative Works

An electromagnetic shielding of objects using ferrite-graphite composites is considered. The analytical model, using the Maxwell Garnett formulation for multiphase mixtures, results of computations based on this model and plane-wave formulation, and some experimental results are represented.


Microwave Reflectometry As A Novel Diagnostic Tool For Detection Of Skin Cancers, Pratik Mehta, Kundan Chand, Deepak Narayanswamy, Daryl G. Beetner, R. Zoughi, William V. Stoecker Aug 2006

Microwave Reflectometry As A Novel Diagnostic Tool For Detection Of Skin Cancers, Pratik Mehta, Kundan Chand, Deepak Narayanswamy, Daryl G. Beetner, R. Zoughi, William V. Stoecker

Electrical and Computer Engineering Faculty Research & Creative Works

More than 1 000 000 people are diagnosed with skin cancer each year in the United States, and more than 10 000 people die from the disease. Methods such as visual inspection and dermoscopy are available for early detection of skin cancers, but improvement in accuracy is needed. This paper investigates the use of microwave reflectometry as a potential diagnostic tool for detection of skin cancers. Open-ended coaxial probes were used to measure microwave properties of skin. The influences of measurement parameters such as probe application pressure, power level, and variation in reflection properties of skin with location and hydration ...


A Method For Charactering Emi Coupling Paths And Source Properties In Complex Systems, Shishuang Sun, Gang Feng, Chong Ding, David Pommerenke, James L. Drewniak Aug 2006

A Method For Charactering Emi Coupling Paths And Source Properties In Complex Systems, Shishuang Sun, Gang Feng, Chong Ding, David Pommerenke, James L. Drewniak

Electrical and Computer Engineering Faculty Research & Creative Works

A method for charactering EMI coupling paths in complex systems is presented. While it is relatively easy to determine the EMI antenna structures or the sources of EMI, it is often quite difficult to identify, and even more difficult to quantify coupling paths. This paper introduces a measurement-based method to quantify EMI coupling paths, and the source strengths can be indirectly determined by applying linear system theory. Circuit design guidelines, e.g., the permissible even-mode current in a differential signal, can be derived with the knowledge of the coupling path and EMI limits. Moreover, the EMI can be better predicted ...