Engineering Commons^™

Discrete-Time Velocity-Based Multiple Model Networks, Ruiyao Gao, Seamus Mcloone, Eugene Dermot Coyle Professor

Conference papers

The velocity-based local model (LM) network is a novel modelling approach that overcomes the lack of interpretability associated with the conventional LM network technique. The global dynamics of the nonlinear network are directly related to the underlying sub-model dynamics. Thus, the velocity-based network is ideally suited to the development of local controller (LC) networks. Furthermore, the local models are continuous-time, velocity-based and linear, providing continuity with established linear theory. To date, research has focused on the continuous-time version of the velocity-based network. The application of digital computer is widely popular in the field of control and, therefore, this paper develops …

A Non-Linear Pid Controller For Cstr Using Local Model Networks, Ruiyao Gao, Aidan O'Dwyer, Eugene Dermot Coyle Professor

Conference papers

The basic PID controllers have difficulty in dealing with problems that appear in complex non-linear processes. This paper presents a practical non-linear PID controller that deals with these non-linear difficulties. It utilises a local model (LM) network, which combines a set of local models within an artificial neural network structure, to adaptively characterise the process non-linearity. Then a local controller network is formulated through a gating system deduced from the LMN to handle the non-linearity. A continuous stirred tank reaction (CSTR) case study illustrates the practicality of this method in the modelling and control of non-linear processes. PID controllers are …

Time Delay Estimation In Signal Processing Applications: An Overview, Aidan O'Dwyer

Conference papers

An extensive though scattered literature exists on the estimation of time delays in signal processing applications. However, it is possible to identify themes that are common to many of the available techniques. The intention of this paper is to provide a framework against which the literature may be viewed. In addition, original work on gradient based time delay estimation is described.

Towards An Expert System Approach For Pi Controller Design Of Delayed Processes, Michael Feeney, Aidan O'Dwyer

Conference papers

This paper will discuss the compensation of first order lag plus time delay (FOLPD) processes using PI controllers whose parameters are specified using appropriate tuning rules. The gain margin and phase margin of the compensated system, as the ratio of time delay to time constant of the process varies, are calculated for each tuning rule and an expert system is used to recommend a tuning rule for user defined requirements.

Regenerative Magnet Load Power Supply With Utility Friendly Operations, M. Sri Balaji, S. P. Das, Gopal Dubey, Malabika Basu

Conference papers

In the present paper, a utility friendly regenerative magnet load power supply has been proposed which can tolerate supply voltage dips and long duration sags or undervoltages and maintains unity input power factor under all operating conditions. The harmonics injected into the utility are much less and the total harmonic distortion (THD) complies with IEEE standards. Unity power factor at the input is maintained by using a synchronous link converter (SLC) as the front-end AC to DC converter with regenerative capability. The two-quadrant chopper in the second stage operates in a constant frequency current control mode and takes care of …

Using Spreadsheet Programs In Teaching Machine Design, Cheng Y. Lin, Gary R. Crossman

Engineering Technology Faculty Publications

This paper presents an approach on using spreadsheets to teach machine design. It also lists detailed procedures on how to implement the teaching scheme. Results show that spreadsheet programs can help students organize their design procedures. By using the characteristics of spreadsheet programs, students do not have to repeat the same calculation and can get the alternate solution of a design almost instantly when given different values on the inputs. When compared to the method taught by using calculators, students can significantly improve their performance on homework problems and tests. From teaching evaluations, their interest in taking such a course …

Experimental Verification Of Derivatives Adaptive Critic Based Neurocontroller Performance On Single Turbogenerators On The Electric Power Grid, Ganesh K. Venayagamoorthy, Donald C. Wunsch, Ronald G. Harley

Electrical and Computer Engineering Faculty Research & Creative Works

The design and real-time implementation of derivatives adaptive critic based neurocontrollers that replace the conventional automatic voltage regulators (AVRs) and turbine governors are presented in this paper. The feedback variables to the neurocontroller are completely based on local measurements from the turbogenerator. Experimental verification results are presented to show the superior performance of the derivatives adaptive critic based neurocontroller, compared to the conventional AVR and turbine governor controllers equipped with a power system stabilizer.

Gunn Oscillators Based On Shielded Dielectric Resonators With Mechanical Frequency Tuning, Sergey Kharkovsky, V. I. Lutsenko, I. V. Lutsenko, V. K. Korneenkov, A. E. Kogut

Electrical and Computer Engineering Faculty Research & Creative Works

The features of Gunn oscillators based on shielded dielectric resonators with whispering gallery modes and ray oscillations are investigated. Their comparative analysis for oscillators with different dielectric resonant structures is carried out.

Improvement Of Power Quality In Vsi Drives, Badrul H. Chowdhury, Ravi Bantu

Electrical and Computer Engineering Faculty Research & Creative Works

The popular VSI (voltage source inverter) drives in use today are mostly PWM (pulse width modulated) drives. Harmonics produced by these drives cause heat losses, reduce the efficiency of the machine and also cause vibrations in the rotor. Active and passive filters are some of the methods to reduce the harmonics generated by these drives. A novel method is discussed which not only eliminates the 5/sup th/ harmonic but also any other negative sequence harmonics. This method, based on a reactor circuit, shows a reduction in harmonics and an improvement in the efficiency of the machine. The method can also …

Tissue Classification Through Analysis Of Gene Expression Data Using A New Family Of Art Architectures, Rui Xu, Georgios C. Anagnostopoulos, Donald C. Wunsch

Electrical and Computer Engineering Faculty Research & Creative Works

Correct classification is crucial to cancer diagnosis and treatment. We demonstrate that a new family of neural network architectures-Ellipsoid ART and ARTMAP (EA/EAM)-can cluster and classify tissues successfully through analysis of gene expression data generated by DNA microarray experiments

A New Control Strategy For The Unified Power Flow Controller, Lin Zhang, Liangying Dong, Mariesa Crow

Electrical and Computer Engineering Faculty Research & Creative Works

The unified power flow controller (UPFC) is the most versatile among a variety of flexible AC transmission system (FACTS) devices, which can be used for power flow control, enhancement of transient stability, damping system oscillations and voltage regulation. In this paper, we propose a new PI based approach for the dynamic control of UPFC. With the new control strategy, not only the active and reactive power flow control but also the system oscillations damping can be achieved. The digital simulation results developed in MATLAB and PSCAD/EMTDC environments are presented to verify the efficiency of the proposed control algorithm.

Best Available Treatment Technologies Applied To Groundwater Circulation Wells, Andrew Curtis Elmore, Thomas Graff

Geosciences and Geological and Petroleum Engineering Faculty Research & Creative Works

Groundwater circulation wells (GCWs) are a quasi-in-situ method for remediating groundwater in areas where remediation techniques that limit the water available for municipal, domestic, industrial, or agricultural purposes are inappropriate. The inherently resource-conservative nature of groundwater circulation wells is also philosophically appealing in today's culture, which is supportive of green technologies. Groundwater circulation wells involve the circulation of groundwater through a dual screen well, with treatment occurring between the screens. The wells are specifically designed so that one well screen draws in groundwater and the second returns the groundwater after it has been treated within the well. Historically, the treatment …

A Unified Theory On Residual Oil Saturation And Irreducible Water Saturation, Nick P. Valenti, R. M. Valenti, Leonard Koederitz

Geosciences and Geological and Petroleum Engineering Faculty Research & Creative Works

In many mature fields, there is a growing debate as to how much of the remaining oil is mobile in the unswept regions versus immobile in the swept regions. Log measured oil saturations behind the flood front are substantially lower than the residual oil saturations measured from special core analysis. In order to explain this contradiction, data from several fields is analyzed with special emphasis on capillary pressure. The concept of irreducible water saturation, connate water saturation, residual oil saturation and "critical water saturation" are discussed. The conclusions which are supported by experiment and theory, have substantial commercial implications concerning …

Interactive Virtual Laboratory For Experience With A Smart Bridge Test, Elizabeth C. Eckhoff, Vicki M. Eller, Steve Eugene Watkins, Richard Hall

Electrical and Computer Engineering Faculty Research & Creative Works

Virtual laboratory experiments can be cost effective, convenient instructional resources that have appeal to a wide range of learning styles. Expensive, time-consuming laboratory tests can be experienced repeatedly and remotely using interactive simulations and original video footage or animations. A virtual experiment can incorporate meaningful exercises, procedural options, and background hyperlinks to create a comprehensive "hands on" environment. Also, it may be used as preliminary training for the actual experiment.

An interactive LabVIEW-based laboratory for a load test simulation of an existing demonstration bridge was created. This smart truss bridge is instrumented with fiber optic strain sensors situated on the …

Comparison Of Mlp And Rbf Neural Networks Using Deviation Signals For Indirect Adaptive Control Of A Synchronous Generator, Jung-Wook Park, Ganesh K. Venayagamoorthy, Ronald G. Harley

Electrical and Computer Engineering Faculty Research & Creative Works

This paper compares the performances of a multilayer perceptron neurocontroller and a radial basis function neurocontroller for backpropagation through time based indirect adaptive control of the synchronous generator. Also, the neurocontrollers are compared with the conventional controller for small as well as large disturbances to the power system

Decoupling Strategies For Printed Circuit Boards Without Power Planes, Todd H. Hubing, Hwan-Woo Shim, Theodore M. Zeeff

Electrical and Computer Engineering Faculty Research & Creative Works

Traditional decoupling capacitors connected between V/CC/ and GND traces can be relatively ineffective at frequencies above their self-resonant frequency. This paper evaluates decoupling capacitor mounting strategies on boards without power planes. Techniques for minimizing mutual inductance and improving decoupling at frequencies above resonance are investigated.

Designing Human-Centered Distributed Information Systems, Jiagie Zhang, Vimla L. Patel, Kathy A. Johnson, Jane Malin, Jack W. Smith

Faculty, Staff and Student Publications

Many computer systems are designed according to engineering and technology principles and are typically difficult to learn and use. The fields of human-computer interaction, interface design, and human factors have made significant contributions to ease of use and are primarily concerned with the interfaces between systems and users, not with the structures that are often more fundamental for designing truly human-centered systems. The emerging paradigm of human-centered computing (HCC)-which has taken many forms-offers a new look at system design. HCC requires more than merely designing an artificial agent to supplement a human agent. The dynamic interactions in a distributed system …

Effect Of Cr3+ And So42- On The Structure Of Rust Layer Formed On Steels By Atmospheric Corrosion, Masato Yamashita, Hitoshi Uchida,, Desmond C. Cook .

Physics Faculty Publications

The effect of chromium ion (Cr³⁺) and sulfate ion (SO₄^2-) on the structure of the rust layer formed by thin electrolyte-film corrosion of low-alloy steels has been examined. By using X-ray diffraction spectroscopy, it was found that coexistence of Cr³⁺ and SO₄^2- in the electrolyte film covering the steel surface quickly forms the Cr-goethite (α-(Fe _1-X, Cr_X)OOH) layer which has been known as the final protective rust layer. Scanning vibrating electrode measurements showed that the rust layer formed under the electrolyte film containing Cr³⁺ and SO₄^{2- …}

Raman Spectroscopy Of Nanocrystalline Ceria And Zirconia Thin Films, Igor Kosacki, Vladimir Petrovsky, Harlan U. Anderson, Philippe Colomban

Materials Science and Engineering Faculty Research & Creative Works

The results of Raman-scattering studies of nanocrystalline CeO₂ and ZrO₂:16% Y (YSZ) thin films are presented. The relationship between the lattice disorder and the form of the Raman spectra is discussed and correlated with the microstructure. It is shown that the Raman line shape results from phonon confinement and spatial correlation effects and yields information about the material nonstoichiometric level.

Misinformation [1], Hollis P. Leighly

Materials Science and Engineering Faculty Research & Creative Works

No abstract provided.

Evaluating And Monitoring Nucleation And Growth In Copper Foil, Ye Kun Lee, Thomas J. O'Keefe

Materials Science and Engineering Faculty Research & Creative Works

The electrodeposition of copper foil for use in electronic materials applications is a complex and demanding process. The specific aspects of producing and controlling the structure-property-performance requirements of the foil are important because of the stringent demands placed on their use in printed circuit boards and similar products. In this paper, a brief review of the electrodeposition process for raw copper foil is presented. Since electrolyte additives play such a significant role in the copper-deposition process, the effects of two essential additives, chloride ion and an organic (e.g., glue or gelatine), on the foil are described. Also, the influence of …

Reactive Hot Pressing Of Alumina-Molybdenum Disilicide Composites, William Fahrenholtz, Ronald E. Loehman, Kevin G. Ewsuk

Materials Science and Engineering Faculty Research & Creative Works

Al₂O₃-MoSi₂ Composites Were Prepared by Reactive Hot Pressing using Molybdenum, Aluminum, and Mullite Powders as Precursors. the Gibbs Free Energy Was Highly Negative for the Composite-Forming Reaction, Which Indicated that the Products Were Stable Relative to the Reactants. after the Reaction, the Composites Had High Relative Density, ∼96%. based on the Composite-Forming Reaction, the Composites Should Have Contained 18 Vol% MoSi₂ in an Al₂O₃ Matrix. Scanning Electron Microscopy Revealed that the MoSi2 Inclusions Were Elongated, with an Average Thickness of ∼5 Μm and Inclusion Lengths that Ranged from 5 to 50 …

A Pneumatically Actuated Manipulandum For Neuromotor Control Research, Aaron J Suminski, Kristina M. Ropella, Robert A. Scheidt

Biomedical Engineering Faculty Research and Publications

Functional magnetic resonance imaging (fMRI) techniques have great potential for identifying which neural structures are involved in the control of goal-directed reaching movements. However, fMRI techniques alone are not capable of probing the neural mechanisms involved in acquisition of novel motor behaviors because such studies require that the moving limb be perturbed in a controlled fashion. We outline a plan to design and develop a non-metallic, pneumatically actuated tool that, along with systems identification techniques and functional magnetic resonance imaging (fMRI), will characterize and quantify how the human central nervous system uses sensory information during practice-based motor learning.

Agglomerated Lubricant, Mary R. Reidmeyer

Materials Science and Engineering Faculty Research & Creative Works

A lubricant for use in lubricating the shot sleeve of a machine for die casting molten metals is in the form of agglomerated particles. The particles have an inorganic high pressure lubricant agglomerated, with a binder material and with an organic material. The solid lubricant is resistant to dusting, caking and breakage, can be fed through an automatic dispensing machine, and combines inorganic and organic materials to achieve excellent lubrication properties. The product has low flash and low smoke release into the environment.

Video Indexing And Retrieval Techniques Using Novel Approaches To Video Segmentation, Characterization, And Similarity Matching, Waleed Ezzat Farag

Computer Science Theses & Dissertations

Multimedia applications are rapidly spread at an ever-increasing rate introducing a number of challenging problems at the hands of the research community, The most significant and influential problem, among them, is the effective access to stored data. In spite of the popularity of keyword-based search technique in alphanumeric databases, it is inadequate for use with multimedia data due to their unstructured nature. On the other hand, a number of content-based access techniques have been developed in the context of image indexing and retrieval; meanwhile video retrieval systems start to gain wide attention, This work proposes a number of techniques constituting …

Increased Mfcc Filter Bandwidth For Noise-Robust Phoneme Recognition, Mark D. Skowronski, John G. Harris

Electrical and Computer Engineering Faculty Research & Creative Works

Many speech recognition systems use mel-frequency cepstral coefficient (MFCC) feature extraction as a front end. In the algorithm, a speech spectrum passes through a filter bank of mel-spaced triangular filters, and the filter output energies are log-compressed and transformed to the cepstral domain by the DCT. The spacing of filter bank center frequencies mimics the known warped-frequency characteristics of the human auditory system, yet the bandwidths of these filters are not chosen through biological inspiration. Instead, they are set by aligning endpoints of the triangle, which is itself an arbitrary shape. It is surprising that for such a popular speech …

The Changing Roles Of Analog And Digital Signal Processing In Cmos Image Sensors, John G. Harris

Electrical and Computer Engineering Faculty Research & Creative Works

Throughout the years digital signal processing has been encroaching more and more into what had previously been exclusive analog circuit domains. Here we briefly summarize various lines of research in CMOS imaging sensoring technology paying special attention to the gradual transition from analog to digital processing. The transition from continuous-time continuous-value pixels to digital (discrete-time binary-value) pixels could be viewed as the natural final step in the evolution of these imaging circuits in order to achieve wide dynamic range with acceptable signal to noise ratio. After data is read off a digital pixel imager chip, digital signal processing is required …

Development Of A Testbed For Design And Evaluation Of Power Electronic Based Systems, S. Pekarek, J. Tichenor, N. Benavides, A. Koenig, H. Wang, Scott D. Sudhoff, B. Kuhn, S. Glover, D. Aliprantis, J. Byoun, J. Sauer

Electrical and Computer Engineering Faculty Research & Creative Works

In this paper, a detailed technical description of a new hardware-based integrated power system testbed is presented. The testbed consists of an AC generation and propulsion system that is coupled to a DC zonal distribution system. A primary objective of the testbed is to provide a resource to the academic and industrial community by providing a non-proprietary system on which to demonstrate controls, survivability algorithms, and validate computer-aided design (CAD) tools. Copyright © 2002 Society of Automotive Engineers, Inc.

Stability Analysis Of A Dc Power Electronics Based Distribution System, Scott D. Sudhoff, Steven Pekarek, S. F. Glover, S. H. Zak, E. Zivi, J. D. Sauer, D. E. Delisle

Electrical and Computer Engineering Faculty Research & Creative Works

This paper illustrates the application of the generalized immittance space approach to the analysis of multi-bus interconnected power electronics-based power distribution system. The paper sets forth the basic classifications of power converters in regard to stability analysis, a set of network reduction transformations, and illustrates the use of these reductions in order to analyze the stability of a zonal dc distribution system. Copyright © 2002 Society of Automotive Engineers, Inc.

End To End Congestion Control In High-Speed Networks, Sarangapani Jagannathan

Electrical and Computer Engineering Faculty Research & Creative Works

This paper proposes an adaptive methodology to prevent congestion in packet switched networks such as the Internet, where the internal network nodes convey very little information to the ingress nodes. Two architectures of preventing the congestion are presented: the first one when the traffic arrival rates, and bottleneck queue levels are known and the other when these are unknown. In the latter, the network traffic is estimated online using an adaptive system by measuring the buffer occupancy. In both architectures, the congestion is controlled by adjusting the transmission rates of non real-time and certain real-time sources in response to the …