Engineering Commons^™

Experimental Evaluation Of A Nested Microphone Array With Adaptive Noise Cancellers, Y. Rosa Zheng, M. El-Tanany, R. A. Goubran

Electrical and Computer Engineering Faculty Research & Creative Works

This paper proposes a near-field broadband adaptive beamforming scheme for intelligent computer telephony and teleconferencing applications, namely the nested microphone array with adaptive noise canceller (NMA-ANC). The NMA-ANC scheme incorporates an harmonically nested array with a nonuniformly subbanded multirate filter bank. Each subband array employs several near-field delay-filter-and-sum beamformers and an adaptive noise canceller (ANC). The proposed NMA-ANC is evaluated via a noise rejection experiment and dereverberation experiment performed in an anechoic chamber and a real conference room, respectively. The experiment data are recorded by a multichannel digital recording system developed using commercial off-the-shelf (COTS) equipments. A perceptual analysis/measurement system …

Inference Of Genetic Regulatory Networks With Recurrent Neural Network Models, Rui Xu, Xiao Hu, Donald C. Wunsch

Electrical and Computer Engineering Faculty Research & Creative Works

Large-scale gene expression data coming from microarray experiments provide us a new means to reveal fundamental cellular processes, investigate functions of genes, and understand relations and interactions among them. To infer genetic regulatory networks from these data with effective computational tools has become increasingly important Several mathematical models, including Boolean networks, Bayesian networks, dynamic Bayesian networks, and linear additive regulation models, have been used to explore the behaviors of regulatory networks. In this paper, we investigate the inference of genetic regulatory networks from time series gene expression in the framework of recurrent neural network model.

Mas-Mom Hybrid Method With Wire's Image Using In Excitation Problems, D. G. Kakulia, David Pommerenke, Kai Xiao, D. D. Karkashadze, K. N. Tavzarashvili, G. N. Ghvedashvili, R. S. Zaridze

Electrical and Computer Engineering Faculty Research & Creative Works

An important class of problems is the interaction of an antenna with the cavity of a semi-open metallic structure. In a working environment, an antenna may change its performance due to interactions with its surroundings. This is especially true in automotive applications. Therefore, it is important to consider the interaction of an antenna with possible resonating parts, and to solve these complex electrodynamics problems together. The development of methods for modeling and studying electromagnetic compatibility (EMC) problems has practical value. The method of auxiliary sources (MAS) with the method of moments (MoM) is applied to solve the excitation problem where …

Modified Takagi-Sugeno Fuzzy Logic Based Controllers For A Static Compensator In A Multimachine Power System, Salman Mohagheghi, Ganesh K. Venayagamoorthy, Ronald G. Harley

Electrical and Computer Engineering Faculty Research & Creative Works

Takagi-Sugeno (TS) based fuzzy logic controllers have been designed for controlling a STATCOM in a multimachine power system. Such controllers do not need any prior knowledge of the plant to be controlled and can efficiently control a STATCOM during different disturbances in the network. Two different approaches for the TS fuzzy logic controller are proposed: a conventional TS fuzzy logic design and a modified TS fuzzy logic design based on shrinking span membership functions. Simulation results, along with a comparison of the conventional TS fuzzy logic controller performance with that of the proposed controller are presented.

Neural Network Based Classification Of Road Pavement Structures, V. Venayagamoorthy, D. Allopi, Ganesh K. Venayagamoorthy

Electrical and Computer Engineering Faculty Research & Creative Works

Roads have formed the basic infrastructure of commerce since flints and other tools and artifacts were first exchanged along the trade routes of prehistory. Roadways are very large, in volume, in extent, and in value. They also wear out, and their useful life is directly proportional to their initial strength and inversely proportional to the number of heavy goods vehicles using them. Therefore, the increasing complexity of road transportation needs advanced techniques for effective design of pavements. This paper proposes an intelligent technique using neural networks to classify different types of road pavement structures, which is essential in estimating bearing …

Optimal Pso For Collective Robotic Search Applications, Ganesh K. Venayagamoorthy, Venu Gopal Gudise, Sheetal Doctor

Electrical and Computer Engineering Faculty Research & Creative Works

Unmanned vehicles/mobile robots are of particular interest in target tracing applications since there are many areas where a human cannot explore. Different means of control have been investigated for unmanned vehicles with various algorithms like genetic algorithms, evolutionary computations, neural networks etc. This work presents the application of particle swarm optimization (PSO) for collective robotic search. The performance of the PSO algorithm depends on various parameters called quality factors and these parameters are determined using a secondary PSO. Results are presented to show that the performance of PSO algorithm and search is improved for a single and multiple target searches.

Robust Resource Allocation For Sensor-Actuator Distributed Computing Systems, Shoukat Ali, Jong-Kook Kim, A. A. Maciejewski, Howard Jay Siegel

Electrical and Computer Engineering Faculty Research & Creative Works

This research investigates two distinct issues related to a resource allocation: its robustness and the failure rate of the heuristic used to determine the allocation. The target system consists of a number of sensors feeding a set of heterogeneous applications continuously executing on a set of heterogeneous machines connected together by high-speed heterogeneous links. There are number of quality of service (QoS) constraints that must be satisfied. A heuristic failure occurs if the heuristic cannot find an allocation that allows the system to meet its QoS constraints. The system is expected to operate in an uncertain environment where the workload, …

A Distributed Power Control Mac Protocol For Wireless Ad-Hoc Networks., Maciej Jan Zawodniok, Jagannathan Sarangapani

Electrical and Computer Engineering Faculty Research & Creative Works

A novel distributed power control (DPC)⋅ scheme and a MAC protocol for wireless ad hoc networks in the presence of radio channel uncertainties such as path loss, Shadowing and Rayleigh fading is presented. The DPC quickly estimates the time-varying nature of the channel and uses the information to select a suitable transmitter power value in order to maintain a target Signal-to-Interference ratio (SIR) at the receiver. The standard assumption of a constant interference during a link's power update used in other works is relaxed. The performance of the proposed DPC is demonstrated analytically. The power used for all RTS-CTS-DATA-ACK frames …

Cost Allocation For Transmission Investment Using Agent-Based Game Theory, Jakapun Mepokee, David Lee Enke, Badrul H. Chowdhury

Engineering Management and Systems Engineering Faculty Research & Creative Works

Due to electrical power restructuring, a dramatic change has been made to the generation and transmission sectors of the power industry. Rules and legislation are continuously changing. To promote more competition, transmission has to be expanded or upgraded to remove congestion and market power. The cost allocation of new investment in transmission has to be recalculated. The socialization methods of the past have been shown to be unfair to some market and network participants. The decentralization of cost allocation must be considered. The proposed paper provides a comparison between traditional cost allocation methods and a new cost allocation method based …

A Preliminary Study Of Maximum System-Level Crosstalk At High Frequencies For Coupled Transmission Lines, H. Weng, Daryl G. Beetner, Todd H. Hubing, R. Wiese, J. Mccallum, Xiaopeng Dong

Electrical and Computer Engineering Faculty Research & Creative Works

Simple formulas were derived to quickly estimate maximum crosstalk between wires in a harness at high frequencies, where the length of circuits is comparable with or greater than the wavelength of the signals of interest. Formulas were derived from multi-conductor transmission line theory. When the source and load resistances are either both large or both small compared to the characteristic impedance of the transmission line, maximum coupling is shown to be given by approximately X_MAX = C_m / (C₂₂ + C_m). A similar equation was found for the case where the load impedances are matched. …

A Taxonomy Of Network Computing Systems, Muthucumaru Maheswaran, Shoukat Ali

Electrical and Computer Engineering Faculty Research & Creative Works

Rapid advances in networking and microprocessor technologies have led to the emergence of Internet-wide distributed computing systems ranging from simple LAN-based clusters to planetary-scale networks. As these network computing systems evolve by combining the best features of existing systems, differences among NCs are blurring. To address this problem, researchers have proposed formal taxonomies of NC systems. We propose a new taxonomy that is both broad enough to encompass all NC systems and simple enough to be widely used.

Adaptive Critics For Dynamic Particle Swarm Optimization, Ganesh K. Venayagamoorthy

Electrical and Computer Engineering Faculty Research & Creative Works

This work introduces a novel technique for dynamic particle swarm optimization (DPSO) using adaptive critic designs. The adaptation between global and local search in an optimization algorithm is critical for optimization problems especially in a dynamically changing environment or process over time. The inertia weight in particle swarm optimization (PSO) is dynamically adjusted in this paper in order to provide a nonlinear search capability for the PSO algorithm. Results on benchmark functions in the literature are provided.

Laboratory Automation Education, James D. Sterling

Business and Information Technology Faculty Research & Creative Works

No abstract provided.

Power Flow And Stability Models For Induction Generators Used In Wind Turbines, Kiran K. Nandigam, Badrul H. Chowdhury

Electrical and Computer Engineering Faculty Research & Creative Works

Model initialization of the induction generator for the wind power generation is investigated. Incorrect initialization may lead to numerical instability problems, not to mention erroneous result from dynamic simulation. The machine model is studied from the perspective of slip and reactive power calculation and tested for various cases. The dynamic reactive power calculation in well-know software package is discussed and the deviation of dynamic reactive power from the steady state reactive power is highlighted.

Partial Discharge On-Line Monitoring For Hv Cable Systems Using Electrooptic Modulators, Paul L. Lewin, David Pommerenke, Simon J. Sutton, Yuan Tian, James S. Wilkinson

Electrical and Computer Engineering Faculty Research & Creative Works

A technique for the remote inspection and monitoring of partial discharge (PD) activity using an optical network is described. The network uses a LiNbO3, modulator to modulate the intensity of the transmitted laser light approximately proportional to the voltage applied across the modulator. The laser light is transmitted along an optical fibre and measured remotely by a high-speed optical receiver. A capacitive coupler has been used to detect partial discharge activity and act as the modulator's input voltage source. The electro-optic modulator is passive and does not require a power supply at the site of the PD detection sensor. The …

A Method For Enhancing The Snapshot Performance In San Volume Manager, Chang-Soo Kim, Dong-Jae Kang, Young-Ho Kim, Hag-Young Kim, Myoung-Jun Kim, Yu-Hyeon Bak

Electrical and Computer Engineering Faculty Research & Creative Works

No abstract provided.

A New Estimative Current Mode Control Technique For Dc-Dc Converters Operating In Discontinuous Conduction Mode, Mehdi Ferdowsi, Zhong Nie, Ali Emadi

Electrical and Computer Engineering Faculty Research & Creative Works

A new digital control technique for power converters operating in discontinuous conduction mode (DCM) is introduced and applied to a boost converter. In contrast to the conventional analogue control methods, the principal idea of this new control scheme is to use real-time analysis and estimate the required on-time of the switch based on the dynamic of the system. The proposed control algorithm can easily be programmed in a digital signal processor (DSP). This novel technique is applicable to any converter operating in DCM including power factor correctors (PFC). However, this work mainly focuses on the boost topology. In this paper, …

An Engineering Primer For Outreach To K-4 Education, Theresa M. Swift, Steve Eugene Watkins

Electrical and Computer Engineering Faculty Research & Creative Works

Student motivation for and proficiency in science and mathematics begin in the early grades. Level-appropriate resources and professional outreach activities are as beneficial for teachers and students at elementary levels as for higher levels. Engineering applications can be effective vehicles for giving students hands-on exposure to technical concepts and for showing students how these concepts relate to everyday life. To improve the technical literacy of society and to promote STEM-related careers, engineers should be engaged in active outreach. However, engineers who seek these types of projects have some learning to do themselves. They must understand the unique elementary education environment …

Preparation And Characterization Of Thermally Stabilized Ceria And Ceria Containing Materials, Leena Ali Rashid Al-Kaabi

Theses

Ceria, CeO₂, is one of the most important catalytic materials that can play multiple roles owing to its ability to release and uptake oxygen under catalytic reaction conditions with the preservation of it fluorite structure. Textural and thermal stability is a critical issue in determining the promoting and metal supporting functions of CeO₂ in its catalytic applications in the three way catalysis. Therefore, significant efforts have been made by industry on finding ways to improve the thermal stability of ceria both by modification of the synthesis of CeO₂ and by looking at possible stabilizers.

In the …

The Role Of The Solid Substrate On The Spreading Kinetics Of A Liquid Droplet, Bashar Jalal Sasa

Theses

Classic hydrodynamic wetting theory leads to a linear relationship between spreading speed and the capillary force, being determined only by the surface tension of the liquid and its viscosity.

The theory appears in good agreement with results generated from experiments conducted on the spreading of Polydimethylsiloxanes (PDMS) on soda-lime glass substrate and fails to account for the behavior of other liquids. This thesis examines the role played by the solid substrate on the spreading kinetics of liquid droplets. The set of experiments whose results are presented below used different types of liquids with various properties of surface tension and viscosity …

Material Selection For A Composite Hip Joint, Ahmed Abdullah Ali Al-Hosani

Theses

The use of biomaterials in orthopedic surgery has been successfully acceptable in the current medical practice. Total hip joint replacement (THR) is one of the most popular and successful operations in orthopedics. Total hip replacement (THR) has been using metal prosthesis for many years. However, the use of metal implants has two major disadvantages. The first disadvantage is that the stiffness of the metallic prosthesis is relatively high compared to the surrounding, load carrying bone. The elastic moduli of titanium and cobalt-chromium alloy are 110 and 210 GPa, respectively. Whereas the elastic modulus of cortical bone ranges from 15 to …

Degree Of Scaffolding: Learning Objective Metadata: A Prototype Leaning System Design For Integrating Gis Into A Civil Engineering Curriculum, Richard H. Hall, Ronaldo Luna, Michael Gene Hilgers, Aaron Joseph Taylor, John Mckenna Sullivan, Matt Buechler

Business and Information Technology Faculty Research & Creative Works

Digital media and networking offer great potential as tools for enhancing classroom learning environments, both local and distant. One concept and related technological tool that can facilitate the effective application and distribution of digital educational resources is learning objects in combination with the SCORM (sharable content objects reference model) compliance framework. Progressive scaffolding is a learning design approach for educational systems that provides flexible guidance to students. We are in the process of utilizing this approach within a SCORM framework in the form of a multi-level instructional design. The associated metadata required by SCORM will describe the degree of scaffolding. …

Chemical Solution Deposition Of Electronic Oxide Films, Robert W. Schwartz, Theodor Schneller, Rainer Waser

Materials Science and Engineering Faculty Research & Creative Works

The chemical solution deposition (CSD) technique as a highly flexible method for the fabrication of electronic oxide thin films is reviewed. Various chemical aspects of different approaches are discussed, including sol-gel, hybrid, and metallo-organic decomposition (MOD) routes, which all have been successfully applied for the deposition of this class of materials. Principles of the selection and properties of the educts, the mechanism of film crystallization, and tailoring of microstructure through manipulation of deposition parameters are reported. the role of thermodynamics on the phase transformation process is also reviewed. Finally, some of the applications for chemical solution-derived thin films currently under …

Forecasting Series-Based Stock Price Data Using Direct Reinforcement Learning, H. Li, Cihan H. Dagli, David Lee Enke

Engineering Management and Systems Engineering Faculty Research & Creative Works

A significant amount of work has been done in the area of price series forecasting using soft computing techniques, most of which are based upon supervised learning. Unfortunately, there has been evidence that such models suffer from fundamental drawbacks. Given that the short-term performance of the financial forecasting architecture can be immediately measured, it is possible to integrate reinforcement learning into such applications. In this paper, we present the novel hybrid view for a financial series and critic adaptation stock price forecasting architecture using direct reinforcement. A new utility function called policies-matching ratio is also proposed. The need for the …

Thermal Efficiency Of Steel Melting, Kent D. Peaslee, Semen Naumovich Lekakh, Bradley Randall

Materials Science and Engineering Faculty Research & Creative Works

This paper presents the results of energy consumption measurements at steel foundries using induction and/or electric arc furnace melting. Statistical methods, infrared thermography, and numerical investigations were used for analysis of heat losses. The influence of different melting practices on energy losses was examined. Industrial experiments in isothermal holding of liquid steel in induction furnaces under different power inputs were used for evaluation of the real values of heat losses by radiation from liquid steel and conductivity through lining. Average values and statistical distributions of energy consumptions for melting steel are presented in this article.

Evaluation Of Microstructure And Superplasticity In Friction Stir Processed 5083 Al Alloy, Indrajit Charit, Rajiv S. Mishra

Materials Science and Engineering Faculty Research & Creative Works

Friction stir processing (FSP) has been developed as a potential grain refinement technique. In the current study, a commercial 5083 Al alloy was friction stir processed with three combinations of FSP parameters. Fine-grained microstructures with average grain sizes of 3.5-8.5 µm were obtained. Tensile tests revealed that the maximum ductility of 590 was achieved at a strain rate of 3 x 10^-3 s^-1 and 530 °C in the 6.5-µm grain size FSP material, whereas for the material with 8.5-µm grain size, maximum ductility of 575 was achieved at a strain rate of 3 x 10^-4 s^{-1 …}

High Gradient Multilayer Insulator Technology, Harlan U. Anderson, Stephen E. Sampayan, G. J. Caporaso, W. C. Nunnally, D. M. Sanders, J. A. Watson, Mike L. Krogh

Materials Science and Engineering Faculty Research & Creative Works

We are investigating a novel insulator concept that involves the use of alternating layers of conductors and insulators with periods less than 1 mm. These structures perform 1.5 to 4 times better than conventional insulators in long pulse, short pulse, and alternating polarity applications. We have surveyed our ongoing studies by investigating the performance under long pulse electron beam, short pulse, and full reversing conditions.

Computation Of Shock Induced Noise In Imperfectly Expanded Supersonic Jets, Bulent Imamoglu

Mechanical & Aerospace Engineering Theses & Dissertations

Screech noise exists only in imperfectly expanded jets. The exit pressure of imperfectly expanded jets does not match ambient pressure, so expansion or compression waves appear out of the nozzle and generate shock cell patterns. Screech is generated by the interaction of shock cells and instability waves. Many experiments and computations have been done to model screech noise, but it is not yet a very well known subject.

A numerical study is performed to understand screech generation mechanisms and to compare with latest experiments. A supersonic underexpanded jet of 25.4 mm diameter is modeled for cases of Mach numbers of …

Position Sensorless Control, Babak Fahimi, Ali Emadi, Raymond B. Sepe

Electrical and Computer Engineering Faculty Research & Creative Works

The switched reluctance machines (SRM) drives applications are studied. the introduction of SRM drives in mission critical applications calls for high levels of survivability and fault tolerance. the various methods are proposed for the sensor less control of SRM drives. the best version of the sensor less technique is selected by continuous monitoring of the back-EMF. the results show that four-quadrant sensor less control of the SRM drive is a feasible technique and can be considered as a technology ready for application.

Innovative Cooling Configurations For Low Emission Gas Turbine Combustors, Ryan Thomas Hebert

LSU Master's Theses

Presently, effective cooling of modern low NOx combustor liners is achieved through combinations of innovative impingement configurations and other heat transfer enhancement methods. An inherent characteristic of conventional impingement configurations is the occurrence of downstream heat transfer degradation due to increased crossflow effects. In the present study, two different impingement configurations are studied. Both impingement configurations examined in this study aim to increase heat transfer effectiveness by reducing the detrimental effects of spent air crossflow. In Part I, a combination technique wherein impingement is combined with ribs placed in between impingement rows is studied. Three configurations with increased rib placements …