Engineering Commons^™

Multiple Damage Detection In Structures Using A Coupled Modal Analysis And Wavelet Transform Technique, Nasser S. Bajabaa

Retrospective Theses and Dissertations

A new technique that couples modal analysis and wavelet transforms for detection of multiple damage in structures is introduced. Structural damage may cause local changes in one or more of the following parameters; stiffness, mass and damping that affect the dynamic behavior of the structure. For example, a crack reduces the stiffness of the structure in a localized sense, and thus reducing its natural frequency, and causes changes in both modal damping and mode shapes. In this research, two different structures have been analyzed: beams and plates. First, uniform beams with a single damage (notch) of different sizes at different …

Multilevel Converter-Based Dual-Frequency Induction Heating Power Supply, B. Diong, S. Basireddy, Keith Corzine

Electrical and Computer Engineering Faculty Research & Creative Works

Most existing power supplies for induction heating equipment produce voltage at a single (adjustable) frequency. Recently, however, induction heating power supplies that produce voltage at two (adjustable) frequencies have been researched and even commercialized. Dual-frequency power supplies are a significant development for heat-treating workpieces with uneven geometries, such as gears, since different portions of such workpieces are heated dissimilarly at a single frequency and so require a two step process using a single-frequency power supply. On the other hand, a dual-frequency power supply can achieve the desired result for such workpieces in a one step process. However, the existing approaches …

Statistical Simulation Models For Rayleigh And Rician Fading, Chengshan Xiao, Y. Rosa Zheng, N. C. Beaulieu

Electrical and Computer Engineering Faculty Research & Creative Works

New simulation models are proposed for Rayleigh and Rician fading channels. First, the statistical properties of Clarke's fading model with a finite number of sinusoids are analyzed. An improved Clarke's model is then proposed for the simulation of Rayleigh fading channels. Based on this improved Rayleigh fading model, a novel simulation model is proposed for Rician fading channels. The new Rician fading model employs a zero-mean stochastic sinusoid as the specular (line-of-sight) component, in contrast to all existing Rician fading simulators that utilize a non-zero mean deterministic specular component. The statistical properties of the proposed Rician fading model are analyzed …

Enhancement Of Output Electric Power In Switched Reluctance Generators, S. Dixon, Babak Fahimi

Electrical and Computer Engineering Faculty Research & Creative Works

This paper introduces a new switching strategy to increase overall productivity for a switched reluctance generator (SRG). This paper presents the idea of using an intermediate freewheeling mode to boost the magnetizing current without taking additional energy from the DC link. Once the optimal motional back-EMF is established, then both switches will be turned off. Although during the freewheeling process no electricity is generated, by proper timing of each region an overall enhancement in productivity of the SRG is achieved. to demonstrate the practicality of the proposed technique, simulation results are provided. These simulations take into account the switching losses …

Example Protein Folds, Dan E. Krane, Michael L. Raymer

Computer Science and Engineering Faculty Publications

Presentation prepared for BIO/CS 471: Algorithms for Bioinformatics. The lecture comprises material from the text Fundamental Concepts of Bioinformatics.

The Structure And Functions Of Proteins, Dan E. Krane, Michael L. Raymer

Computer Science and Engineering Faculty Publications

Presentation prepared for BIO 271/CS 399: Bioinformatics. The lecture comprises material from the text Fundamental Concepts of Bioinformatics.

A New Modified Smith Predictor Design, Pauline Sourdille, Aidan O'Dwyer

Conference papers

A new modified Smith predictor structure is presented with its associated tuning rules.

The Effect Of Processing Conditions On Varistors Prepared From Nanocrystalline Zno, Suresh Pillai, Declan Mccormack, John Kelly, Ramesh Raghavendra

Articles

Nanoparticles of ZnO were prepared by the reaction of ethanolic solutions of zinc acetate and oxalic acid
followed by drying (80 uC) and calcination (500 uC). Subsequently varistor materials were fabricated from this
nanoparticular ZnO via two separate routes:- a) from a ‘‘core shell’’ material using metal salts as additives; b)
by using a conventional solid state mixing of metal oxides. Sintering (1050 uC) and subsequent electrical studies
were carried out for each of these samples and they were compared with commercial varistor samples prepared
under similar conditions. ‘‘Core shell’’ type varistor material showed considerably higher breakdown voltage
(Vc ~ …

Enhanced Magnetoresistance In Nanocrystalline Magnetite, M Venkatesan, S. Nawka, Suresh Pillai, Jm D. Coey

Articles

The magnetic and magnetotransport properties of nanoparticulate magnetite with different grain
sizes are investigated using x-ray diffraction, microscopy, magnetometry, and magnetoresistance
measurements. The magnetization varies significantly with grain size and is sensitive to preparation conditions. The reduction in saturation magnetization in coprecipitated particles is probably due to the surface spin disorder. Magnetoresistance of pressed powder compacts is significantly enhanced
in material composed of small grain size magnetite particles prepared by coprecipitation. Useful
magnetoresistance persists well above room temperature in sintered ceramic material.

Impulse, Dave Graves, Kyle Johnson, Megan Koch

Impulse (Jerome J. Lohr College of Engineering Publication)

Features:
[Page] 2 Crothers ready for the next generation
[Page] 4 Energy lab ranks among the finest in the country
[Page] 7 Teenagers build fun into Youth Engineering Adventure
[Page] 8 Crothers makes life easier for those with disabilities
Students:
[Page] 10 Joint Engineering Council impresses companies at job Fair
[Page] 12 Students meet challenges of studying, performing
[Page] 15 ME students create blimp for indoor athletic events
[Page] 16 Design project aids ADVANCE workers at door manufacturer
Faculty:
[Page] 17 Grant to broaden access to remote sensing data
[Page] 18 New faces, new positions
[Page] 20 Faculty news
College: …

The Strength Of Stiffened Cfs Floor Joist Assemblies With Offset Loading, S. R. Fox

American Iron and Steel Institute (AISI) Specifications, Standards, Manuals and Research Reports (1946 - present)

No abstract provided.

Modeling Intracranial Fluid Flows And Volumes During Traumatic Brain Injury To Better Understand Pressure Dynamics, Wayne W. Wakeland, James Mcnames, Mateo Aboy, D. Hollemon, Brahm Goldstein

Complex Systems Faculty Publications and Presentations

See additional files below for the Presentation.

We describe a computer model of intracranial pressure (ICP) dynamics that evaluates clinical treatment options for elevated ICP during traumatic brain injury (TBI). The model uses fluid volumes as primary state variables and explicitly models fluid flows as well as the resistance, compliance, and pressure associated with each intra - and extracranial compartment (arteries and arterioles, capillary bed, veins, venous sinus, ventricles, and brain parenchyma). The model evaluates clinical events and therapies such as intra - and extra-parenchymal hemorrhage, cerebral edema, cerebrospinal fluid drainage, mannitol administration, head elevation, and mild hyperventilation. The model …

On The Analysis Of Small Displacements Of Truss Joints, Clive L. Dym, Harry E. Williams

All HMC Faculty Publications and Research

By emphasizing the kinematic aspects and implications of strain in truss analysis, it is shown that joint displacements can be computed in a straightforward manner.

Acuta Enews January 2003, Vol. 32, No. 1

ACUTA Newsletters

In This Issue

Priorities for 2003

The Web Portal: Access to Campus Service.................. Jeanne Jansenius, Univ. of the South

Pumping Up Copper Can Buy You Bandwidth and Time............... Kevin Tanzillo, Dux Public Relations

ACUTA Alert: FCC Requires ITFS Licensees to Review Data

Be a State/Province Coordinator..................... Kellie Bowman, ACUTA Membership Development Mgr.

Wireless Service Coverage Problems Persist In-building................ James McCoy, Innerwireless, Inc

Board Report............................ John Bradley, Rensselar Polytechnic Institute

Thanks to Journal Advertisers for 2002

DC Update........................... Whitney Johnson, Retired, Northern Michigan Univ.

ACUTA Member Sites to See

Prepare for Take-off: Travel Tips........................... Jeri Semer, CAE, Executive Director

Welcome New …

Scale-Up Of The Fermentation And Purification Of The Recombinant Heavy Chain Fragment C Of Botulinum Neurotoxin Serotype F, Expressed In Pichia Pastoris, Scott K. Johnson, Wenhui Zhang, Leonard A. Smith, Karen J. Hywood-Potter, S. Todd Swanson, Vicki L. Schlegel, Michael M. Meagher

Michael Meagher Publications

A recombinant heavy chain fragment C of botulinum neurotoxin serotype F (BoNTF(Hc)) has been expressed in Pichia pastoris for use as an antigen in a proposed human vaccine. P. pastoris cells were grown using glycerol batch, glycerol fed-batch, and methanol fedbatch methods to achieve high cell densities. The total cellular protein recovered after homogenization was 72 mg/g of cell paste. BoNTF(Hc) was purified from soluble Pichia cell lysate employing ion-exchange chromatographic (IEC) and hydrophobic interaction chromatographic (HIC) methods developed at the bench scale using 10–100mL columns. The process was performed at the pilot scale using 1–4 L columns for evaluation …

Evaluation Of Scheduling Strategies On The Performance Of A Flexible Manufacturing Cell:A Simulation Study, Amr Arisha, Paul Young, Mohie El Baradie

Conference papers

The current trend in semiconductor manufacturing is characterized by expanding product variety, decreasing lead times from order to delivery, exacting standards of quality, and competitive prices. One possible means of achieving this is in the form of increased flexibility. Providing flexibility is typically an expensive proposition so, industrial engineers aim to provide more economic approaches to enable flexible manufacturing cells and related equipment to operate appropriately in an efficient manner. It is essential to characterize these tools in detail before the production plans are finalized. Using state-of-the-art computer simulation, a generic model of photolithography tools has been developed. The model …

Fragment Assembly Of Dna, Dan E. Krane, Michael L. Raymer

Computer Science and Engineering Faculty Publications

Presentation prepared for BIO/CS 471: Algorithms for Bioinformatics. The lecture comprises material from the text Fundamental Concepts of Bioinformatics.

Computer Modeling Of Tornado Forces On A Cubic Building Using Large Eddy Simulation, R. Panneer Selvam, Paul C. Millett

Journal of the Arkansas Academy of Science

A tornado changes its wind speed and direction rapidly; therefore, it is difficult to study the effects of a tornado on buildings in a wind tunnel. The status of the tornado-structure interaction and various models of the tornado wind field found in literature are surveyed. Three dimensional computer modeling work using the turbulence model based on large eddy simulation is presented. The effect of a tornado on a cubic building is considered for this study. The Navier-Stokes (NS) equations are approximated by the finite difference method and solved by an implicit procedure. The force coefficients are plotted in time to …

Adaptive Critic Designs And Their Implementations On Different Neural Network Architectures, Jung-Wook Park, Ganesh K. Venayagamoorthy, Ronald G. Harley

Electrical and Computer Engineering Faculty Research & Creative Works

The design of nonlinear optimal neurocontrollers based on the Adaptive Critic Designs (ACDs) family of algorithms has recently attracted interest. This paper presents a summary of these algorithms, and compares their performance when implemented on two different types of artificial neural networks, namely the multilayer perceptron neural network (MLPNN) and the radial basis function neural network (RBFNN). As an example for the application of the ACDs, the control of synchronous generator on an electric power grid is considered and results are presented to compare the different ACD family members and their implementations on different neural network architectures.

Particle Trapping In Stratified Estuaries - Definition Of A Parameter Space, David A. Jay, Philip M. Orton, Thomas A. Chisholm, Douglas J. Wilson, Annika M. Fain, John Mcginity

Civil and Environmental Engineering Faculty Publications and Presentations

Estuarine turbidity maxima (ETM) retain suspended particulate matter (SPM) through advection, settling, aggregation and non-linearities in bed processes. This contribution defines for the first time a parameter space descriptive of ETM water-column particle trapping processes through a scaling analysis of the local and integral SPM balances. In the absence of long-term deposition, there are five primary parameters for the large particles or aggregates that are typically trapped. Rouse number P, the ratio of settling velocity WS of the SPM relative to the shear velocity U*, describes the material trapped in the ETM in terms of the local vertical balance between …

Public Street Surveillance: A Psychometric Study On The Perceived Social Risk, David J. Brooks

Theses: Doctorates and Masters

Public street surveillance, a domain of Closed Circuit Television (CCTV), has grown enormously and is becoming common place with increasing utilization in society as an all-purpose security tool. Previous authors (Ditton, 1999; Davies, 1998; Horne, 1998; Tomkins, 1998) have raised concern over social, civil and privacy issues, but there has been limited research to quantify these concerns. There are a number of core aspects that could relocate the risk perception and therefore, social support of public street surveillance. This study utilized the psychometric paradigm to quantitatively measure the social risk perception of public street surveillance. The psychometric paradigm is a …

Environmental Management Of Waste Electrical & Electronic Equipment (Weee) In Ireland, Simon Wilkinson

Theses

This thesis follows two previous studies by the Author on the calculation of theoretical WEEE arisings, and an assessment of ecodesign practices in Ireland. It has established collection trials in five different locations throughout Ireland in order to characterise and quantify WEEE arisings, and to examine outlets for collected WEEE. Overall, during the twelve months of collection at the project locations, more than 450 tonnes of WEEE was collected from the public and recycled. Within the catchments of each facility, collection rates of between 2.1 and 3.5 kg/person/year were achieved during the twelve-month trial period. With further public awareness raising …

Analytical And Fea Analysis Of Silicon Micro-Machined Capacitive Pressure Sensor, Eoghan O'Donoghue

Theses

This thesis is concerned with the electro-mechanical characterisation of MEMS capacitive pressure sensors and the determination of models to describe their behaviour.

The finite element software package ANSYS is validated as a tool for the examination of the electro-mechanical behaviour of capacitive pressure sensors. It is then used to incorporate the effects of applied load, voltage and residual stress into a model of the sensor structure. The capacitive pressure sensor is modelled both in 3D and also in 2D axis-symmetric modes. The error between the 2D and 3D models is quantified.

The behaviour of structures under electrostatic actuation is investigated. …

Automated Distribution And Management Of Software And Hardware Configurations For Heterogeneous Wireless Devices, Grainne Foley

Theses

The continuing evolution of wireless networks and services has increased the complexity and diversity of wireless networks and devices, placing significant emphasis on the need for flexible device configuration management. Widely varying wireless technologies currently operate independently worldwide, making global wireless network access for the mobile user confusing and unwieldy. New technologies, network access methodologies and improved services further obscure the evolving environment. The focus of effort for this thesis is the development of a system to automate the distribution and management of software and hardware configurations that enable different levels of wireless device reconfiguration. The scope of investigation will …

Modern Control Techniques For Induction Machines In High-Performance Adjustable-Speed Drives, Pat Cronin

Theses

Induction Motors (IM’s) are increasingly being considered for and used in high-performance motor drive (HPMD) systems. Their application has only gained acceptance since the 1970’s with the advent of vector control, microprocessors and improvements in power converter technology. D.C. motors were traditionally the preferred choice in HPMD systems. The main reasons for IM acceptance in HPMD systems are ruggedness, durability, low maintenance, cost, and small size by comparison with D.C. motors.

Alternating current asynchronous motors of the IM type are considered to be the universal workhorses of the manufacturing industry. It has been estimated that they are used in seventy …

Extraction Of A Valuable Compound From A Waste Stream For Adm Ringaskiddy, Colin G. Burkley

Theses

This thesis was originally conceived as a potential Masters Degree research programme by the management of ADM Ringaskiddy as a means of maximizing throughput through the plant’s wastewater treatment facility. This facility is a major producer of citric acid using beet molasses and a fermentation process. It was proposed that removal of a compound, known as betaine, from the citric acid process waste stream would reduce the Chemical Oxygen Demand (COD) content of the waste requiring treatment before disposal. This would be achieved by using the citric acid process waste as the feedstock for a betaine extraction process. The wastewater …

Thermal Assessment Of Silicon-Based Composite Materials Used In Photovoltaics, Pavlos K. Bataglannis

Theses

Photovoltaics are devices that convert sunlight directly to electricity. It is well established that the conversion efficiency of mono and poly-crystalline silicon-based photovoltaic modules is inversely related to their temperature. Substantial improvements in operational performance can thus be achieved if the thermal energy accumulating in the material can be effectively dissipated.

Accurate modelling of modules would allow possible methods of thermal dissipation to be evaluated, and as a crucial component of the model, the thermal properties of the constituent materials of PV modules needed to be known. Special consideration needed to be given to the interfaces between dissimilar materials and …

Modeling Sugarbeet Quality Variables From Satellite Images And Canopy Spectral Indices, Subodh Kulkarni

Electronic Theses and Dissertations

Remote sensing was used to model crop quality from measurements of canopy spectra. Three indices of canopy characteristics, derived from satellite image data, were tested for relationship to whole-field sugarbeet quality. Quality was quantified as recoverable sucrose per ton of harvested sugarbeets. Quality data were extracted from the year 2002 Field Database of the Southern Minnesota Beet Sugar Co-operative, (SMBSC), Renville, Minnesota. Linear regression models utilizing canopy indices and changes in canopy indices over time were tested for relationship to sugarbeet quality for four classes of sugarbeets. Classes of sugarbeet tested represented fields planted to a mix of varieties resistant …

Nonlinear Time Series Prediction By Weighted Vector Quantization, Amaury Lendasse, D. Francois, V. Wertz, M. Verleysen

Engineering Management and Systems Engineering Faculty Research & Creative Works

Classical Nonlinear Models for Time Series Prediction Exhibit Improved Capabilities Compared to Linear Ones. Nonlinear Regression Has However Drawbacks, Such as overfilling and Local Minima Problems, User-Adjusted Parameters, Higher Computation Times, Etc. There is Thus a Need for Simple Nonlinear Models with a Restricted Number of Learning Parameters, High Performances and Reasonable Complexity. in This Paper, We Present a Method for Nonlinear Forecasting based on the Quantization of Vectors Concatenating Inputs (Regressors) and Outputs (Predictions). Weighting Techniques Are Applied to Give More Importance to Inputs and Outputs Respectively. the Method is Illustrated on Standard Time Series Prediction Benchmarks. © Springer-Verlag …

Evolving Digital Circuits Using Particle Swarm, Ganesh K. Venayagamoorthy, Venu Gopal Gudise

Electrical and Computer Engineering Faculty Research & Creative Works

Particle swarm optimization (PSO) motivated by the social behavior of organisms is proposed for evolution of combinational logic circuits. Results are presented to show that PSO based evolution of digital circuits are equivalent to or even with better solutions (with minimum number of logic gates) than that of a human designer and other genetic algorithm (GA) based techniques. This PSO based approach converges faster than other approaches reported in literature using genetic algorithms and as a result the computational intensity involved in hardware evolution is reduced. Examples taken from the literature are used to evaluate the performance of the proposed …