Engineering Commons^™

A Microphone Array System For Multimedia Applications With Near-Field Signal Targets, Y. Rosa Zheng, M. El-Tanany, R. A. Goubran, Hongchi Shi

Electrical and Computer Engineering Faculty Research & Creative Works

A microphone array beamforming system is proposed for multimedia communication applications using four sets of small planar arrays mounted on a computer monitor. A new virtual array approach is employed such that the original signals received by the array elements are weighted and delayed to synthesize a large, nonuniformly spaced, harmonically nested virtual array covering the frequency band [50, 7000] Hz of the wideband telephony. Subband multirate processing and near-field beamforming techniques are then used jointly by the nested virtual array to improve the performances in reverberant environments. A new beamforming algorithm is also proposed using a broadband near-field spherically …

An Embedded Real-Time Neuro-Fuzzy Controller For Mobile Robot Navigation, Nian Zhang, Daryl G. Beetner, Donald C. Wunsch, B. Hemmelman, Ahmad Hasan

Electrical and Computer Engineering Faculty Research & Creative Works

A reactive fuzzy logic based control strategy was developed for mobile robot navigation. To decrease the number of fuzzy rules and related processing, a RAM-based neural network was combined with the fuzzy logic strategy. The fuzzy rules are used to interpret sensor information. The neural network uses results from the fuzzy logic as well as environmental information to make navigation decisions. The feasibility of this neuro-fuzzy approach was demonstrated on a mobile robot using a simple, 8-bit microcontroller. Experiments show the approach works well, as the robot was able to successfully avoid objects while seeking a goal in real-time. The …

Segmental Dynamics In Poly(Methyl Acrylate)-D3 On Strongly And Weakly Adsorbing Silica Surfaces, Burak Metin, Frank D. Blum

Chemistry Faculty Research & Creative Works

The segmental dynamics of a polymer on a solid surface appears to be significantly different than that in bulk. The strength of the interaction between polymer segments and a solid surface is likely to be an important factor affecting the segmental mobility of the polymers. Studies of polymers on a weakly adsorbing surface would provide additional understanding of their motional characteristics on surfaces. In a recent NMR study by Rivillon et al., chain dynamics was seen to be different for samples, even when there was no specific interaction with the surface. Peanasky et al. have found a restricted segmental dynamics …

A Warped Bandwidth Expansion Filter, Marc A. Boillot, John G. Harris

Electrical and Computer Engineering Faculty Research & Creative Works

A warped filter is presented as a new speech enhancement method to adjust formant bandwidths on a critical band scale. The warped filter enhances perceived loudness without adding signal energy by exploiting the psychoacoustic nature of the auditory system. The critical band concept in auditory theory states that when the energy in a signal remains constant, loudness increases when the energy spreads beyond a critical bandwidth. A warped filter is proposed and developed to elevate the perceived loudness of clean speech by applying non-linear bandwidth expansion to the formant regions of vowels in accordance with the critical band scale. The …

Disordered Speech Evaluation Using Objective Quality Measures, Lingyun Gu, John G. Harris, Rahul Shrivastav, Christine Sapienza

Electrical and Computer Engineering Faculty Research & Creative Works

Speech quality assessment methods are necessary for evaluating and documenting treatment outcomes of patients suffering from degraded speech due to Parkinson's disease, stroke or other disease processes. Subjective methods of speech quality assessment are more accurate and more robust than objective methods but are time-consuming and costly. We propose a novel objective measure of speech quality assessment that builds on traditional speech processing techniques such as dynamic time warping (DTW) and the Itakura-Saito (IS) distortion measure. Initial results show that our objective measure correlates well with the more expensive subjective methods. © 2005 IEEE.

Network-Centric First Responder Architecture With Swarming Robots Entity, Lakshmanan Meyyappan, Cihan H. Dagli

Engineering Management and Systems Engineering Faculty Research & Creative Works

This paper proposes a new network centric architecture that can be used by first responders to effectively respond to crisis situations. The powerful network-centric concept originally developed for and mainly used in the military environment, can be effectively used for civilian security and emergency response missions. This paper also proposes the use of a swarm of intelligent robots as a part of the network-centric architecture to aid the first responders. The swarm of robots works in tandem with the first responders and provides them with the necessary information on a real time basis. The proposed network centric architecture with a …

Shadow Detection By Combined Photometric Invariants For Improved Foreground Segmentation, Filiz Bunyak, Ilker Ersoy, S. R. Subramanya

Electrical and Computer Engineering Faculty Research & Creative Works

Detection and tracking of moving objects are the essential steps of many video understanding applications such as traffic monitoring, video surveillance and visual event recognition. Moving object detection process segments the scene into foreground (moving) and background regions. Moving cast shadows cause serious problems in this process because they can easily be misclassified as foreground. This misclassification may lead to drastic changes in the shapes of objects or merging of multiple objects. in this paper, we present a method to detect moving cast shadows to improve the performance of moving object detection. the foreground regions are processed in terms of …

The Inns President's Welcome, Donald C. Wunsch

Electrical and Computer Engineering Faculty Research & Creative Works

No abstract provided.

A Multi-Hypothesis Approach For Salient Object Tracking In Visual Surveillance, Filiz Bunyak, Ilker Ersoy, S. R. Subramanya

Electrical and Computer Engineering Faculty Research & Creative Works

In this paper, a multiple object tracking method for visual surveillance applications is presented. Moving objects are detected by adaptive background subtraction and tracked by using a multi-hypothesis testing approach. Object matching between frames is done based on proximity and appearance similarity. a new confidence measure is assigned to each possible match. This information is arranged into a graph structure where vertices represent blobs in consecutive frames and edges represent match confidence values. This graph is later used to prune and refine trajectories to obtain the salient object trajectories. Occlusions are handled through position prediction using Kalman filter and robust …

Greetings From The Technical Program Chair, Steve Eugene Watkins

Electrical and Computer Engineering Faculty Research & Creative Works

No abstract provided.

Wide Area Power System Protection Using A Learning Vector Quantization Network, Ganesh K. Venayagamoorthy, Mahyar Zarghami

Electrical and Computer Engineering Faculty Research & Creative Works

This paper presents a wide area monitoring and protection technique based on a learning vector quantization (LVQ) neural network. Phasor measurements of the power network buses are monitored continuously by a LVQ network in order to alert the control room operators of possible faults. The proposed scheme could be used in a wide area monitored network to provide remedial action when primary local protection schemes for transmission lines fail to function. This technique could also be extended to the actuation of the secondary protection schemes, hence, preserving the integrity of the power network especially when the faults are spreading over …

A Neural Network Based Optimal Wide Area Control Scheme For A Power System, Ganesh K. Venayagamoorthy, Swakshar Ray

Electrical and Computer Engineering Faculty Research & Creative Works

With deregulation of the power industry, many tie lines between control areas are driven to operate near their maximum capacity, especially those serving heavy load centers. Wide area control systems (WACSs) using wide-area or global signals can provide remote auxiliary control signals to local controllers such as automatic voltage regulators, power system stabilizers, etc to damp out inter-area oscillations. This paper presents the design and the DSP implementation of a nonlinear optimal wide area controller based on adaptive critic designs and neural networks for a power system on the real-time digital simulator (RTDS©). The performance of the WACS as a …

Block Phase Correlation-Based Automatic Drift Compensation For Atomic Force Microscopes, Qinmin Yang, Eric W. Bohannan, Jagannathan Sarangapani

Electrical and Computer Engineering Faculty Research & Creative Works

Automatic nanomanipulation and nanofabrication with an Atomic Force Microscope (AFM) is a precursor for nanomanufacturing. In ambient conditions without stringent environmental controls, nanomanipulation tasks require extensive human intervention to compensate for the many spatial uncertainties of the AFM. Among these uncertainties, thermal drift is especially hard to solve because it tends to increase with time and cannot be compensated simultaneously by feedback. In this paper, an automatic compensation scheme is introduced to measure and estimate drift. This information can be subsequently utilized to compensate for the thermal drift so that a real-time controller for nanomanipulation can be designed as if …

Calibration And Compensation Of Near-Field Scan Measurements, Masahiro Yamaguchi, Richard E. Dubroff, Kevin P. Slattery, Michael A. Cracraft, Jin Shi

Electrical and Computer Engineering Faculty Research & Creative Works

A procedure for the calibration and compensation of near-field scanning is described and demonstrated. Ultimately, the objective is to quantify the individual field components associated with electromagnetic interference (EMI) from high speed circuitry and devices. Specific examples of these methods are shown. The effects of compensation are small but noticeable when the uncompensated output signal from near field scanning is already a very good representation of the field being measured. In other cases, the improvement provided by compensation can be significant when the uncompensated output signal bears little resemblance to the underlying field.

Double-Tiered Capacitive Shuttling Method For Balancing Series-Connected Batteries, 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 capacity imbalances stemming from the cell manufacturer, ensuing driving environment, and operational usage affect voltage levels, which must follow adherence to strict limits to ensure the safety of the driver. A variation on an existing method of using a capacitor to shuttle charge from one battery to another to balance series strings of batteries is proposed in this paper. The advancement shown in this paper is to bridge …

Effects Of A Statcom, A Scrc And A Upfc On The Dynamic Behavior Of A 45 Bus Section Of The Brazilian Power System, Ganesh K. Venayagamoorthy, Salman Mohagheghi, Wei Qiao, Swakshar Ray, Ronald G. Harley, Djalma M. Falcao, Glauco N. Taranto, Tatiana M. L. Assis, Yamille Del Valle

Electrical and Computer Engineering Faculty Research & Creative Works

No abstract provided.

Engine Data Classification With Simultaneous Recurrent Network Using A Hybrid Pso-Ea Algorithm, Xindi Cai, Donald C. Wunsch

Electrical and Computer Engineering Faculty Research & Creative Works

We applied an architecture which automates the design of simultaneous recurrent network (SRN) using a new evolutionary learning algorithm. This new evolutionary learning algorithm is based on a hybrid of particle swarm optimization (PSO) and evolutionary algorithm (EA). By combining the searching abilities of these two global optimization methods, the evolution of individuals is no longer restricted to be in the same generation, and better performed individuals may produce offspring to replace those with poor performance. The novel algorithm is then applied to the simultaneous recurrent network for the engine data classification. The experimental results show that our approach gives …

Estimation Of Additive Noise Variance For Multiuser Cdma Systems, Jingxian Wu, Chengshan Xiao, Khaled Ben Letaief

Electrical and Computer Engineering Faculty Research & Creative Works

In this paper, a novel additive noise variance estimation algorithm is proposed for multiuser CDMA systems experiencing time varying and frequency selective fading. The algorithm is developed by exploring the eigen-structure of the receive signal correlation matrix, which is characterized by the statistid properties of both the fading channeI and the additive white Gaussian noise. Relying only on the knowledge of the receiver signal samples, the algorithm can accurately estimate the variance of the additive noise present at the receiver of multiuser CDMA systems. The estimated noise variance can be employed along with other receiver algorithms to improve system performance.

Image Recognition Systems With Permutative Coding, Ernst M. Kussul, Donald C. Wunsch, Tatiana N. Baidyk

Electrical and Computer Engineering Faculty Research & Creative Works

A feature extractor and neural classifier for image recognition system are proposed. They are based on the permutative coding technique which continues our investigations on neural networks. It permits us to obtain sufficiently general description of the image to be recognized. Different types of images were used to test the proposed image recognition system. It was tested on the handwritten digit recognition problem, the face recognition problem and the shape of microobjects recognition problem. The results of testing are very promising. The error rate for the MNIST database is 0.44% and for the ORL database is 0.1%.

Improving The Performance Of Particle Swarm Optimization Using Adaptive Critics Designs, Ganesh K. Venayagamoorthy, Sheetal Doctor

Electrical and Computer Engineering Faculty Research & Creative Works

Swarm intelligence algorithms are based on natural behaviors. Particle swarm optimization (PSO) is a stochastic search and optimization tool. Changes in the PSO parameters, namely the inertia weight and the cognitive and social acceleration constants, affect the performance of the search process. This paper presents a novel method to dynamically change the values of these parameters during the search. Adaptive critic design (ACD) has been applied for dynamically changing the values of the PSO parameters.

Optimal Dynamic Neurocontrol Of A Gate-Controlled Series Capacitor In A Multi-Machine Power System, Swakshar Ray, Ganesh K. Venayagamoorthy, Edson H. Watanabe, F. D. De Jesus

Electrical and Computer Engineering Faculty Research & Creative Works

This paper presents the design of an optimal dynamic neurocontroller for a new type of FACTS device - the gate controlled series capacitor (GCSC) incorporated in a multi-machine power system. The optimal neurocontroller is developed based on the heuristic dynamic programming (HDP) approach. In addition, a dynamic identifier/model and controller structure using the recurrent neural network trained with backpropagation through time (BPTT) is employed. Simulation results are presented to show the effectiveness of the dynamic neurocontroller and its performance is compared with that of the conventional PI controller under small and large disturbances.

Power System Optimization And Coordination Of Damping Controls By Series Facts Devices, Jung-Wook Park, Ganesh K. Venayagamoorthy, Ronald G. Harley

Electrical and Computer Engineering Faculty Research & Creative Works

No abstract provided.

Two Separate Continually Online-Trained Neurocontrollers For A Unified Power Flow Controller, Ganesh K. Venayagamoorthy, Radha P. Kalyani

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 (UPFC) provides an effective means for controlling the power flow and improving the transient stability in a power network. The UPFC has fast complex dynamics and its conventional control is based on a linearized model of the power system. This paper presents the design of neurocontrollers to provide better damping during transient and dynamic control. Two separate neurocontrollers are used for controlling the UPFC, one neurocontroller for the shunt inverter and the other for the series inverter. Simulation studies carried out in …

Cad Model Extraction Of Pcb Signal Discontinuity Using A Circuit Extraction Approach Based On Mixed-Potential Integral Equation Formulation, Shaofeng Luan

Doctoral Dissertations

"In high-speed digital design, signal via transitions on printed circuit boards (PCBs) are becoming an important signal integrity issue. Efficient and accurate models for via transitions are necessary to analyze high bit-rate digital circuit system. The circuit extraction approach based on a mixed-potential integral equation formulation (CEMPIE) is an extension of the Partial Element Equivalent Circuit approach (PEEC) to general multi-layered media. CEMPIE was further developed to include the horizontal current components on the vertical surface and extended to model the discontinuities on multilayer PCBs. A procedure of building SPICE models for signal via transitions between printed circuit board layers …

Esd Susceptibility Characterization Of An Eut By Using 3d Esd Scanning System, Kai Wang, Jayong Koo, Giorgi Muchaidze, David Pommerenke

Electrical and Computer Engineering Faculty Research & Creative Works

Electrostatic discharges (ESD) can lead to soft-errors (e.g., bit-errors, wrong resets etc.) in digital electronics. The use of lower threshold voltages and faster I/O increases the sensitivity. In the analysis of ESD problems, an exact knowledge of the affected pins and nets is essential for an optimal solution. In this paper, a three dimensional ESD scanning system which has been developed to record the ESD susceptibility map for printed circuit board is presented and the mechanisms that the ESD event couples into the digital devices is studied. The ESD susceptibility of a fast CMOS EUT is characterized by generating the …

Manpower Development: Industry And Educators Need To Work Together, Peter W. Sauer, Mani Venkata, Mariesa Crow

Electrical and Computer Engineering Faculty Research & Creative Works

No abstract provided.

Effect Of Engine Operating Conditions On The Size And Morphology Of Diesel Particulate Emissions, Adam Neer

Masters Theses

"The size, morphology and volume fraction of sub-micron particulate matter emitted from a compression ignition (diesel) engine was investigated using thermophoretic sampling experiments followed by direct visual characterizations under transmission electron microscopy. Specifically, measurements were conducted at the exhaust of a 6059T John Deere, 5.9 L, 6 cylinder, turbocharged, direct injection diesel engine. The particles observed were composed of nearly spherical primary particles (spherules) that formed aggregates of various sizes and shapes. The size distributions of spherules and aggregates were separately measured to obtain the available surface area, which is crucial for estimating the environmental and health impact of particles. …

Application Of Laser Aided Manufacturing Process For Functionally Graded Thermal Barrier Coatings, Yashodhan Joshi

Masters Theses

"Laser Aided Manufacturing Process (LAMP) is a rapid prototyping process used to build three dimensional functional metal and ceramic parts. The process developed in the LAMP laboratory at University of Missouri-Rolla uses a 5-axis fadal CNC machine and a 2.5 KW Nd:YAG (TEM₀₀) Rofin Sinar laser. The laser power and metal/ceramic powder are the input along with auxiliary systems such as shielding gas delivery, RT data acquisition, coolant system. The hybrid process makes use of metal deposition and machining to obtain parts meeting design tolerances.

LAMP is used to improve upon the process of Thermal Barrier Coating (TBC) …

Characteristics Of Laser Forming Austenitic Stainless Steel Alloys, Jack Robert Pennuto

Masters Theses

"This thesis discusses the investigation of laser forming austenitic stainless-steel alloys for the development of free curve and complex shapes...Previous work in this area has focused on the development of single angle laser forming and process optimization for the development of multi-dimensional shapes. This thesis seeks to discuss the relationship of multiple parallel laser passes and any coupling effects that may exist for the class of austenitic stainless steels, including any metallurgical implications"--Abstract, page iii.

Continuous Solidification Of Yba2cu3o7−X By Isothermal Undercooling, Fatih Dogan

Materials Science and Engineering Faculty Research & Creative Works

Growth kinetics and microstructural development of single crystal YBa₂Cu₃O_7−x (Y123) superconductors, prepared by a melt texturing method under isothermal undercooling conditions, were investigated. At small undercooling, ΔT = 6 K, the initial growth of Y123 crystal was terminated at a size of ∼8 mm × 8 mm in the semisolid phase before the entire sample was fully solidified through the peritectic reaction. With incremental increase of ΔT, the growth of the crystal continued so that the whole sample (22 mm diameter and 8 mm thickness) solidified as a single crystal. Termination of the crystal growth …