Digital Commons Network^™

Correlation Between Eut Failure Levels And Esd Generator Parameters, Jayong Koo, Qing Cai, Kai Wang, J. Maas, T. Takahashi, Andrew Martwick, David Pommerenke

Electrical and Computer Engineering Faculty Research & Creative Works

Some system-level electrostatic discharge (ESD) tests repeat badly if different ESD generators are used. For improving repeatability, ESD generator specifications have been changed, and modified generators have been compared in a worldwide round robin test. The test showed up to 1 : 3 variations of failure levels. Multiple parameters that characterize ESD generators have been measured. This paper correlates the parameters to test result variations trying to distinguish between important and nonrelevant parameters. The transient fields show large variations among different ESD generators. A correlation has been observed in many equipment under tests (EUTs) between failure levels and the spectral …

Plurality Of Principal Angles For A Given Pseudo-Brewster Angle When Polarized Light Is Reflected At A Dielectric-Conductor Interface, R. M.A. Azzam, A. Alsamman

Electrical Engineering Faculty Publications

The pseudo-Brewster angle ϕpB of minimum reflectance for p-polarized light and the principal angle ϕ¯ at which incident linearly polarized light of the proper azimuth is reflected circularly polarized are considered as functions of the complex relative dielectric function ε of a dielectric–conductor interface over the entire complex ε plane. In particular, the spread of ϕ¯for a given ϕpB is determined, and the maximum difference (ϕ¯−ϕpB)max is obtained as a function of ϕpB . The maximum difference (ϕ¯−ϕpB)max approaches 45° and 0 in the limit as ϕpB→0 and 90°, respectively. ForϕpB<22.666° , multiple principal angles ϕ¯i , i=1,2,3 , appear for each ε in a subdomain of fractional optical constants. …

Cmol/Cmos Hardware Architectures And Performance/Price For Bayesian Memory - The Building Block Of Intelligent Systems, Mazad Shaheriar Zaveri

Dissertations and Theses

The semiconductor/computer industry has been following Moore's law for several decades and has reaped the benefits in speed and density of the resultant scaling. Transistor density has reached almost one billion per chip, and transistor delays are in picoseconds. However, scaling has slowed down, and the semiconductor industry is now facing several challenges. Hybrid CMOS/nano technologies, such as CMOL, are considered as an interim solution to some of the challenges. Another potential architectural solution includes specialized architectures for applications/models in the intelligent computing domain, one aspect of which includes abstract computational models inspired from the neuro/cognitive sciences.

Consequently in this …

System And Technique For Retrieving Depth Information About A Surface By Projecting A Composite Image Of Modulated Light Patterns, Laurence G. Hassebrook, Daniel L. Lau, Chun Guan

Electrical and Computer Engineering Faculty Patents

A technique, associated system and program code, for retrieving depth information about at least one surface of an object. Core features include: projecting a composite image comprising a plurality of modulated structured light patterns, at the object; capturing an image reflected from the surface; and recovering pattern information from the reflected image, for each of the modulated structured light patterns. Pattern information is preferably recovered for each modulated structured light pattern used to create the composite, by performing a demodulation of the reflected image. Reconstruction of the surface can be accomplished by using depth information from the recovered patterns to …

Design Of An Ic Controller For A Light Emitting Diode Stack, Andrew Alleman

All Theses

An integrated circuit (IC) powering up to nine series connected high brightness light emitting diodes (HBLED's) was designed. The LED's are split into three groups by color (RGB), and the average current through each group is independently varied using a separate microprocessor in conjunction with the IC controller. Integrated comparators compare the voltage across each LED group with internally generated references to check for open or short circuit diodes. In the event of an open circuit failure, the IC controller switches in a SCR to bypass the open circuit device thus maintaining light output at reduced intensity.
Silvaco CAD tools …

Investigation Of Across-Layer Modification To The Dsr Routing Protocol In Wireless Mesh Networks, Mustafa Ramadhan, Mark Davis

Conference papers

This work introduces a cross-layer modification to the DSR protocol that increases the global throughput in wireless mesh networks. In our modified DSR protocol we have introduced the Access Efficiency metric as an alternative to the hop-count metric in order to improve the route selection mechanism. The selected path in the route selection mechanism is identified by choosing the path with the highest minimum Access Efficiency value. We have employed the OPNET modeller as a simulator to examine two different patterns of traffic for a series of randomly generated network topologies. Each topology was simulated twice. One simulation used the …

Effects Of Lline Rate On Vvideo Qos Over Wireless Networks: An Experimental Approach, Stuart Wallace, Mark Davis

Conference papers

Video streaming over Wireless Local Area Networks (WLANS) is becoming an increasingly popular service. However, end user OoS is highly influenced by many factors. These include the video codec used, the packetization scheme, error concealment and correction techniques, the complexity of the video, propagation losses, and the line rate. In this paper the effect of the line rate on the capacity of the network when streaming multimedia content is analyzed experimentally. It is shown that as the line rate decreases the bandwidth load of the video stream dramatically increases leading to poor QoS at the client side. As automatic line …

Theory And Application Of Motion Compensation For Lfm-Cw Sar, David G. Long, Evan C. Zaugg

Faculty Publications

Small low-cost high-resolution synthetic aperture radar (SAR) systems are made possible by using a linear frequency-modulated continuous-wave (LFM-CW) signal. SAR processing assumes that the sensor is moving in a straight line at a constant speed, but in actuality, an unmanned aerial vehicle (UAV) or airplane will often significantly deviate from this ideal. This nonideal motion can seriously degrade the SAR image quality. In a continuous-wave system, this motion happens during the radar pulse, which means that existing motion compensation techniques that approximate the position as constant over a pulse are limited for LFM-CW SAR. Small aircraft and UAVs are particularly …

Temperature (5.6-300k) Dependence Comparison Of Carrier Transport Mechanisms In Hfo2/Sio2 And Sio2 Mos Gate Stacks, Richard G. Southwick Iii, Justin Reed, Christopher Buu, Hieu Bui, Ross Butler, G. Bersuker, William B. Knowlton

Electrical and Computer Engineering Faculty Publications and Presentations

Temperature dependent measurements have been used to examine transport mechanisms and energy band structure in MOS devices. In this study, a comparison between high-k HfO₂ dielectrics and conventional SiO₂ dielectrics is made to investigate dielectric specific thermally activated mechanisms. Temperature dependent measurements on large area n/pMOSFETs composed of SiO₂ and HfO₂/SiO₂ gate dielectrics were performed from 5.6 K to 300 K. A large increase in the gate leakage current is observed at the formation of the minority carrier channel. The data indicate that gate leakage current prior to the formation of the minority channel …

New Power Quality Index In A Distribution Power System By Using Rmp Model, Soon Lee, Jung-Wook Park, Ganesh K. Venayagamoorthy

Electrical and Computer Engineering Faculty Research & Creative Works

In this paper, a new power quality index (PQI), which is directly related to the generation of distortion power from nonlinear harmonic loads, is introduced to determine their harmonic pollution ranking in a distribution power system. The electric load composition rate (LCR) and the total harmonic distortion (THD) for the estimated currents on each harmonic load are used to define the proposed PQI. The reduced multivariate polynomial (RMP) model with one-shot training property is applied to realize the PQI. Then, the ranking of distortion power for each nonlinear load, which have adverse effect on the entire system, is determined. It …

Optimal Estimation Of Calibration Parameters In Polarimetric Microwave Radiometers, David G. Long, Derek Hudson

Faculty Publications

Methods for internal calibration of a certain class of microwave polarimetric radiometers are presented by Piepmeier. In that work, the calibration parameters are estimated algebraically. We demonstrate that Bayesian estimation decreases the root-mean-square error of the estimates by a factor of two. This improvement is obtained by using knowledge of the noise structure of the measurements and by utilizing all of the information provided by the measurements. Drawbacks are the increased complexity of the method and an increase in computation. We also extend the method to estimate several hardware component parameters of interest in system calibration.

Estimation Of Hurricane Winds From Seawinds At Ultrahigh Resolution, David G. Long, Brent A. Williams

Faculty Publications

Although the SeaWinds scatterometer was not specifically designed to observe tropical cyclones, new high-resolution wind products resolve much of the horizontal structure of these storms. However, these higher resolution products (2.5 km) are inherently noisier than the standard 25-km near-surface wind products. These noise levels combined with rain contamination complicate high-resolution wind estimation-particularly in tropical cyclones. Fortunately, tropical cyclones have structures that can be exploited by using a wind field model. This paper develops a new procedure for hurricane wind field estimation from the SeaWinds instrument at ultrahigh resolution. A simplified hurricane model is developed to provide prior information to …

Adaptive And Probabilistic Power Control Algorithms For Rfid Reader Networks, 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 will suffer from interference among high power reading devices. This problem grows severely and degrades system performance in dense RFID networks. Consequently, medium access protocols (MAC) protocols are needed for such networks to assess and provide access to the channel so that tags can be read accurately. In this paper, we investigate a suite of feasible power control schemes to ensure overall coverage area of the system while maintaining a desired read rate. The power control scheme and MAC protocol dynamically adjusts the RFID reader power output in …

Canonical Correlation Feature Selection For Sensors With Overlapping Bands: Theory And Application, Biliana S. Paskaleva, Majeed M. Hayat, Zhipeng Wang, J. Scott Tyo, Sanjay Krishna

Electrical and Computer Engineering Faculty Research and Publications

The main focus of this paper is a rigorous development and validation of a novel canonical correlation feature- selection (CCFS) algorithm that is particularly well suited for spectral sensors with overlapping and noisy bands. The proposed approach combines a generalized canonical correlation analysis framework and a minimum mean-square-error criterion for the selection of feature subspaces. The latter induces ranking of the best linear combinations of the noisy overlapping bands and, in doing so, guarantees a minimal generalized distance between the centers of classes and their respective reconstructions in the space spanned by sensor bands. To demonstrate the efficacy and the …

Aerial And Satellite Image Processing Applications, Srinivas K. Jakkula

Electrical & Computer Engineering Theses & Dissertations

Aerial and satellite images are used extensively in many trip and mapping software packages, such as Google Earth etc. Aerial images differ significantly due to the variations in atmospheric clarity, atmospheric layer density, humidity, temperature, and season under which the aerial images are captured. Among the issues in effective utilization of aerial images, color tone discrepancy is the inconsistency in brightness, saturation, or color balance between images representing adjacent areas, causing adjacent areas appear significantly different that would otherwise be similar. Aenal images are also routinely used as ground textures to simulate Earth surface and 3D features on Earth in …

Biomarker Identification For Prostate Cancer Using An Efficient Feature Selection Algorithm, Vamsi Krishnam Raju Mantena

Electrical & Computer Engineering Theses & Dissertations

In recent years, there has been an increased interest in using protein mass spectrometry to identify biomarkers that discriminate diseased from healthy individuals. A biomarker is a characteristic that is objectively measured and evaluated as an indicator of normal biological processes, pathological processes, or pharmacological responses to a therapeutic intervention. Identifying biomarkers will be an important step towards disease characterization and patient management. One challenge of biomarker identification is how to handle the high dimensional mass spectral data. In this thesis, we applied an efficient feature selection algorithm to mass spectrometry data obtained from prostate tissue samples to identify prostate …

A Systematic Study On Structural And Optical Properties In Conjugated Polymer Photovoltaic Devices, Sri Sabarinadh Sunkavalli

Electrical & Computer Engineering Theses & Dissertations

Conjugated polymer/fullerene based solar cells represent an exciting alternative to inorganic ones because of their low production costs, flexibility and low weight. At present, commercialization of organic photovoltaic (OPV) cells is limited due to their relatively low efficiency in comparison to silicon ones. In order to understand the operation of OPV cells and to increase their efficiency, more information about the structure of the absorber layer is needed. In particular, the connection between structure and properties of the absorber layer is of great importance. Performance of bulk heterojunction organic solar cells based on poly (3-hexylthiophene) as donor and a soluble …

The Development Of Genetic Algorithm For The Prediction Of Ship Motion From Wave Radar Data, Sumanth Tirumala Vangipuram

Electrical & Computer Engineering Theses & Dissertations

Genetic Algorithms represent a model of natural process based on the Darwinian principle of evolution. Genetic algorithms are used to solve optimization problems by generating a set of possible solutions and determining which of these solutions most closely match the desired result. The Genetic Algorithm (GA) initially generates a random set of possible solutions, or populations, determines which members of the population are most desirable, and calculates better solutions by implementing genetic operations such as reproduction, cloning, and mutation. Problems where the evaluation of a solution is computationally simple enable the GA to search a vast search space. One of …

Geo-Rectification Of Aerial Images For Detecting Changes In Terrain, Diana Vincent

Electrical & Computer Engineering Theses & Dissertations

With increasing terrorist attacks around the world, detection of hidden bombs like IEDs (Improvised Explosive devices) has become very important. The main aim of this thesis is to develop an automatic change detection system to detect changes in terrain. It is mainly used in military applications for protection of military convoys. In order to detect the presence of IED's, an Unmanned Aerial Vehicle (UAV) is flown over a proposed convoy route to develop a baseline scene. Prior to the launch of the convoy the UA V is flown again over the same route to detect any significant scene changes that …

Education Enhancement Using Visualization And Simulation Tools For Basic Circuit Theory Concepts, Jariwala Rajvi Prakashchandra

Electrical & Computer Engineering Theses & Dissertations

New generation web-technologies and supporting development tools have prompted opportunities for developing new methods of teaching and learning. Web-based visualization and simulation modules developed for ODU's ECE201 Circuit Theory course are presented in this thesis. Visualization and simulation methodology is used to make learning process more interactive and effective. Macromedia FLASH software, which has the extensive graphical animation capabilities, is used to develop visualization modules. Lab VIEW is a leading graphical development tool for science and engineering with a built-in functionality for simulation, data acquisition, instrument control, measurement analysis and data presentation. These capabilities are utilized to develop web-based simulation …

A Pressure Sensing System Using Fiber Optic Sensors And Artificial Neural Networks, Xiaomin Jin, Xiao-Hua Yu, Saied Zarger, Roshan H. Patel, Sam Wards

Electrical Engineering

No abstract provided.

A Sawtooth Waveform Inspired Pitch Estimator For Speech And Music, Arturo Camacho, John G. Harris

Electrical and Computer Engineering Faculty Research & Creative Works

A sawtooth waveform inspired pitch estimator (SWIPE) has been developed for speech and music. SWIPE estimates the pitch as the fundamental frequency of the sawtooth waveform whose spectrum best matches the spectrum of the input signal. The comparison of the spectra is done by computing a normalized inner product between the spectrum of the signal and a modified cosine. The size of the analysis window is chosen appropriately to make the width of the main lobes of the spectrum match the width of the positive lobes of the cosine. SWIPE′, a variation of SWIPE, utilizes only the first and prime …

Minimally Invasive Capacitive Micromachined Ultrasonic Transducers Array For Biomedical Applications, Xiaoyang Cheng

Electrical and Computer Engineering ETDs

Ultrasound covers a broad range of applications from underwater exploration and nondestructive evaluation of materials to medical diagnosis and treatment. The ultrasonic transducer plays an important role in determining the resolution, sensitivity, as well as other critical diagnostic capabilities of an ultrasonic detection or imaging system. Currently piezoelectric ultrasonic transducers dominate the market. The device performance of the piezoelectric ultrasonic transducer in medical applications is limited by the material properties and related electrical and acoustic impedance match issues. The fabrication of piezoelectric transducer array requires meticulous handcrafting. It is difficult and expensive to fabricate densely populated piezoelectric array. The Capacitive …

Description Of Versatile Optical Polarimetric Scatterometer That Measures All 16 Elements Of The Mueller Matrix For Reflection And Transmission: Application To Measurements Of Scatter Cross Sections, Ellipsometric Parameters, Optical Activity, And The Complex Chiral Parameters, Ezekiel Bahar, Robert D. Kubik

Department of Electrical and Computer Engineering: Faculty Publications

A detailed description of an optical polarimetric scatterometer, its capabilities, and special application are presented. This instrument measures the 44 Mueller matrix elements as well as bidirectional reflective distribution functions scatter cross sectionsfor light that is scattered from a target. Incident polarized light at wavelengths =0.6328 and =1.06 m can be directed toward the target in an arbitrary direction. The receiver can be located anywhere in the solid angle 4. Backscatter measurements, most commonly used in remote sensing, can also be obtained. The scatterometer has been used to validate different analytical/numerical solutions to a broad class of electromagnetic scattering problems, …

Modeling Of Space-Charge-Limited Current Injection Incorporating An Advanced Model Of The Poole-Frenkel Effect, Satoshi Takeshita

All Theses

The current flow due to Space-Charge-Limited (SCL) emission is well known and the associated current-voltage power law relationship can be observed in many materials, particularly in insulators and semiconductors. Under an applied field, the space-charge effect occurs due to the carrier injection, and the resulting current due to the presence of the space-charge effect is referred to as SCL current. In the SCL current theory, the presence of localized traps in a material has a significant effect on the transport of injected carriers; however, in the first order SCL model, the trap barrier height is assumed to be constant for …

Neural Network Dimension Selection For Dynamical System Identification, Devin Sabo, Xiao-Hua Yu

Electrical Engineering

Choosing an appropriate size of a network is an important issue for any neural network applications. The common practice is to start with an “over-sized” network, then gradually reduces its size to find the optimal solution. In this paper, a new hybrid neural network pruning algorithm for multi-layer feedforward neural networks is investigated. Computer simulation results on system identification and pattern classification problems show this algorithm can significantly reduce the network dimension while still maintaining satisfactory identification and classification accuracy.

Swarm Intelligence And Evolutionary Approaches For Reactive Power And Voltage Control, Ganesh K. Venayagamoorthy, G. Krost, G. A. Bakare, Lisa L. Grant

Electrical and Computer Engineering Faculty Research & Creative Works

This paper presents a comparison of swarm intelligence and evolutionary techniques based approaches for minimization of system losses and improvement of voltage profiles in a power network. Efficient distribution of reactive power in an electric network can be achieved by adjusting the excitation on generators, the on-load tap changer positions of transformers, and proper switching of discrete portions of inductors or capacitors. This is a mixed integer non-linear optimization problem where metaheuristics techniques have proven suitable for providing optimal solutions. Four algorithms explored in this paper include differential evolution (DE), particle swarm optimization (PSO), a hybrid combination of DE and …

Single-Phase Bidirectional Ac-Dc Converters For Plug-In Hybrid Electric Vehicle Applications, Lisheng Shi, Andrew Meintz, Mehdi Ferdowsi

Electrical and Computer Engineering Faculty Research & Creative Works

Plug-in hybrid electric vehicles (PHEVs) are specialized hybrid electric vehicles that have the potential to obtain enough energy for average daily commuting from batteries. These batteries would be charged from the power grid and would thus allow for a reduction in the overall petroleum consumption. To implement the plug-in function, a single phase bidirectional AC-DC converter interfacing with the grid is essential. The implementation of a bidirectional AC-DC converter can allow for battery recharge from the grid, battery energy injection to the AC grid, and battery energy for AC power stabilization. In this paper, the basic requirements and specifications for …

Hardware Implementations Of Swarming Intelligence -- A Survey, Cameron Eric Johnson, Parviz Palangpour, Ganesh K. Venayagamoorthy

Electrical and Computer Engineering Faculty Research & Creative Works

Swarming intelligence (SI) is the property of a system whereby the collective behaviors of (unsophisticated) agents interacting locally with their environment cause coherent global patterns to emerge. Because there are no central processing requirements, SI is ideal for parallelization, which lends it well to hardware implementations in many inexpensive processors. Several implementations in hardware that exploit this property for rapid calculation and inexpensive construction are highlighted in this paper to provide a good starting point for developing hardware platforms for SI algorithms.

Development And Validation Of A Microcontroller Model For Emc, Shaohua Li, Hemant Bishnoi, Jason Whiles, Pius Ng, Haixiao Weng, David Pommerenke, Daryl G. Beetner

Electrical and Computer Engineering Faculty Research & Creative Works

Models of integrated circuits (ICs) allow printed circuit board (PCB) developers to predict radiated and conducted emissions early in board development and allow IC manufactures insight into how to build their ICs better for electromagnetic compatibility (EMC). A model of the power delivery network, similar to the ICEM or LECCS model, was developed for a microcontroller running a typical program and used to predict the noise voltage between the power and return planes of a PCB. The IC and package model was generated using the Apache tool suite. A model of the PCB was created using an electromagnetic cavity model …