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Articles 12211 - 12240 of 21751

Full-Text Articles in Engineering

Material Properties Of Cold-Formed High Strength Stainless Steel Tubular Sections, Ben Young, Wing-Man Lui Nov 2004

Material Properties Of Cold-Formed High Strength Stainless Steel Tubular Sections, Ben Young, Wing-Man Lui

CCFSS Proceedings of International Specialty Conference on Cold-Formed Steel Structures (1971 - 2018)

This paper presents the behaviour of cold-formed high strength stainless steel sections. The test specimens were cold-rolled from flat strips of duplex and high strength austenitic stainless steel. The material properties of high strength stainless steel square and rectangular hollow sections were determined. Tensile coupons at different locations in cross-section were tested. Hence, the distributions of 0.2% proof stress and tensile strength measured in the cross-section of cold-formed high strength stainless steel sections were plotted. The material properties of the complete cross-section in the cold-worked state were also obtained from stub column tests. Detailed measurements of initial local geometric imperfections …

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Stainless Steel Stub Columns Subject To Combined Bending And Axial Loading, M. Macdonald, J. Rhodes Nov 2004

Stainless Steel Stub Columns Subject To Combined Bending And Axial Loading, M. Macdonald, J. Rhodes

CCFSS Proceedings of International Specialty Conference on Cold-Formed Steel Structures (1971 - 2018)

Stainless steel exhibits highly non-linear behaviour, and in the case of short column structural members, this can lead to substantial conservatism in the prediction of load capacity by design codes due to their use of the 0.2% proof stress as an upper limit of capacity. This paper examines the behaviour of short stainless steel stub columns in which the material follows a Ramberg-Osgood type of stress-strain law. The column length is varied to examine the effects on the load capacity when the column is subjected to varying magnitudes of combined bending and axial compression loading. The loading is applied as …

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Quantification Of Solids Flow In A Gas-Solid Riser: Single Radioactive Particle Tracking, Satish Bhusarapu, Muthanna H. Al-Dahhan, Milorad P. Dudukovic Nov 2004

Quantification Of Solids Flow In A Gas-Solid Riser: Single Radioactive Particle Tracking, Satish Bhusarapu, Muthanna H. Al-Dahhan, Milorad P. Dudukovic

Chemical and Biochemical Engineering Faculty Research & Creative Works

Solids in Risers of Circulating Fluidized Beds (CFB) Exhibit Local Backflow and Recirculation. Measurement of the Concentration-Time Response to an Impulse Injection of Tracer, Even at Two Elevations Cannot Determine the Residence Time Distribution (RTD) of Solids Uniquely. Hence, Evaluation of RTD in Risers from Conventional Tracer Responses is Difficult and Often Not Possible. in Addition, Estimating the Solids Circulation Rate in These Closed Loop Systems, is a Non-Trivial Problem. in This Work, a Single Radioactive Particle in the CFB Loop is Tracked during its Multiple Visits to the Riser And, by Invoking Ergodicity, Solids Circulation Rate, Accurate Solids RTD …

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Single Chamber Electrolyte Supported Sofc Module, Toshio Suzuki, Piotr Jasinski, Harlan U. Anderson, Fatih Dogan Nov 2004

Single Chamber Electrolyte Supported Sofc Module, Toshio Suzuki, Piotr Jasinski, Harlan U. Anderson, Fatih Dogan

Materials Science and Engineering Faculty Research & Creative Works

An electrolyte supported single chamber solid oxide fuel cell (SOFC) module consisting of two cells has been proposed. The module consists of one Sm-doped CeO2 (SDC) electrolyte substrate (0.5 mm thick with the size of 5 3 10 mm), two Ni-SDC anodes on one side, and two SDC-(La,Sr)(Co,Fe)O3 cathodes on the other side. Two modules with different electrode areas were prepared and tested using an air-propane mixture. The electrode area had a strong influence on the performance of the module. It was shown that the two-cell module generated 1.5 V open-circuit voltage and about 17 mW maximum power …

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Versatile Hardware And Software Tools For Educating Students In Power Electronics, Joshua M. Williams, James L. Cale, Nicholas D. Benavides, Jeff D. Wooldridge, Andreas C. Koenig, Jerry L. Tichenor, Steven D. Pekarek Nov 2004

Versatile Hardware And Software Tools For Educating Students In Power Electronics, Joshua M. Williams, James L. Cale, Nicholas D. Benavides, Jeff D. Wooldridge, Andreas C. Koenig, Jerry L. Tichenor, Steven D. Pekarek

Electrical and Computer Engineering Faculty Research & Creative Works

A new power electronics laboratory has been constructed at the University of Missouri - Rolla. Key components of the laboratory are a set of custom- designed hardware and software tools. the novel hardware tools include five mobile power electronics testbeds that each contain the semiconductor devices, gate-drive boards, voltage and current sensors, and computer interface connections required to study a wide range of circuit topologies and control techniques. Novel software tools include a set of virtual instruments used for control, data capture, and data analysis. a description of these tools, along with their use in power electronics courses, laboratory exercises, …

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Optimization Of Batch Reactions In Series With Uncertainty, Keith G. Tomazi Nov 2004

Optimization Of Batch Reactions In Series With Uncertainty, Keith G. Tomazi

Chemical and Biochemical Engineering Faculty Research & Creative Works

Certain types of chemical reactions, such as the global deprotection of a polypeptide, are extremely complex. As a result, it may be very difficult or expensive to develop accurate models of these chemical reactions. Without a satisfactory kinetic model for the reaction, it is difficult to develop an optimum operating policy that will maximize the profit. Stochastic optimization is applied in this work to an example process step to obtain the optimum reaction temperature and reaction time. In the case of the "here and now" problem, the optimal conditions are a lower reaction temperature and a longer reaction time than …

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Monoliths As Multiphase Reactors: A Review, Shaibal Roy, Tobias Bauer, Muthanna H. Al-Dahhan, Peter Lehner, Thomas Turek Nov 2004

Monoliths As Multiphase Reactors: A Review, Shaibal Roy, Tobias Bauer, Muthanna H. Al-Dahhan, Peter Lehner, Thomas Turek

Chemical and Biochemical Engineering Faculty Research & Creative Works

Monolith Reactors Are Being Studied as a Replacement for Conventional Multiphase Reactors Such as Trickle-Bed Reactors, Slurry Reactors, and Slurry Bubble Column Reactors for Gas-Liquid-Solid Reactions. Reactors with Monolith Catalyst Packing Have Been Found to Be Hydrodynamically Superior to Existing Industrial Reactors. This Review Covers Multiphase Reactions Carried Out in Monolith Reactors by Various Researchers. It First Defines the Monolith Reactor and Looks into the Geometrical Aspects of Monolith. the Section Dealing with Hydrodynamics Reviews Pressure Drop, Phase Holdup, Flow Distribution, and Dispersion Characteristics. This Study Also Considers the Tools Used to Characterize the Hydrodynamic Parameters and their Typical Values. …

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Liquid Holdup And Pressure Drop In The Gas-Liquid Cocurrent Downflow Packed-Bed Reactor Under Elevated Pressures, Jing Guo, Muthanna H. Al-Dahhan Nov 2004

Liquid Holdup And Pressure Drop In The Gas-Liquid Cocurrent Downflow Packed-Bed Reactor Under Elevated Pressures, Jing Guo, Muthanna H. Al-Dahhan

Chemical and Biochemical Engineering Faculty Research & Creative Works

An Experimental Investigation of the Residence Time Distribution, Liquid Holdup, and Pressure Drop in a Gas-Liquid Downflow Packed Bed Reactor with Porous Particles Operated under Elevated Pressures is Presented. the Effects of the Two-Phase Flow Rates and Reactor Pressures on the External Liquid Holdup and Pressure Drop Are Discussed. a Mechanistic Model, Which Accounts for the Interaction between the Gas and Liquid Phases by Incorporating the Shear and Velocity Slip Factors between Phases, is Employed to Predict the External Liquid Holdup and Pressure Drop for the Experimentally Covered Flow Regime. the Involved Parameters, Such as Shear and Velocity Slip Factors …

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Strength Of Screw Connections Subject To Shear Force, Michael Rotimi Babalola, Roger A. Laboube Nov 2004

Strength Of Screw Connections Subject To Shear Force, Michael Rotimi Babalola, Roger A. Laboube

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

No abstract provided.

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Assessment Of Engineering Mechanics Instructional Multimedia In A Variety Of Instructional Settings, Richard H. Hall, Nancy Hubing, Timothy A. Philpot, Ralph E. Flori, Vikas Yellamraju Oct 2004

Assessment Of Engineering Mechanics Instructional Multimedia In A Variety Of Instructional Settings, Richard H. Hall, Nancy Hubing, Timothy A. Philpot, Ralph E. Flori, Vikas Yellamraju

Business and Information Technology Faculty Research & Creative Works

Students from Ten Schools, Representing Seven Countries, Used Interactive Multimedia as a Part of their Engineering Statics Classes. the Software Consisted of Four Modules, Which Focused On: Mohr's Circle; Centroid and Moment of Inertia; Stress Transformation; and Structural Analysis. the Students Completed On-Line Surveys About their Experience with the Software. Analysis of the Results Indicated that Students Rated their Knowledge of the Subject Matter Covered in the Software as Increasing Significantly as a Consequence of using the Software. However, This Increase Was Substantially More Pronounced for Students in U.S. Schools. Students Rated the Software as Significantly More Effective Than their …

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Rare Earth-Aluminum Oxide Glasses For Optical Applications, Richard Weber, Jean A. Tangeman, Paul C. Nordine, Richard N. Scheunemann, Kirsten J. Hiera, Chandra S. Ray Oct 2004

Rare Earth-Aluminum Oxide Glasses For Optical Applications, Richard Weber, Jean A. Tangeman, Paul C. Nordine, Richard N. Scheunemann, Kirsten J. Hiera, Chandra S. Ray

Materials Science and Engineering Faculty Research & Creative Works

Glasses based on rare earth oxides and aluminum oxide with 0-20 mol% SiO2 provide a combination of optical properties, mechanical and chemical stability, and process characteristics not available in other oxide materials. Properties of the glasses include: refractive index 1.7-1.8, low dispersion (Abbe number ∼40), high solubility of optically active dopants, homogeneous chemical composition, long fluorescence lifetimes at dopant concentrations up to 5 mol%, broad fluorescence bandwidth, and infra-red transmission to ≈5000nm. the glasses are hard, strong and resist chemical attack and they can be cast in sections 5-10mm thick. This paper briefly describes glass processing and presents bulk …

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Solvent And Method For Extraction Of Triglyceride Rich Oil, Shubhender Kapila, Paul Ki-Souk Nam, V. J. Flanigan Oct 2004

Solvent And Method For Extraction Of Triglyceride Rich Oil, Shubhender Kapila, Paul Ki-Souk Nam, V. J. Flanigan

Chemistry Faculty Research & Creative Works

The present invention relates to a solvent for use in extracting oil from an oil bearing material, such as soybeans, with the solvent resulting in the selective extraction of a triglyceride rich oil, which contains 95% or greater triglycerides and non-polar constituents, with the solvent comprised of a hydrocarbon, preferably hexane, and a fluorocarbon, so that the solvent has a viscosity less than 2.6 centipoise and a polarity of less than 0.1. The present invention also relates to a method of using the solvent to extract the triglyceride rich oil, with the method including preferably extracting the oil at a …

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Bracing Requirements Of Cfs Cee-Studs Subjected, Perry S. Green, Thomas Sputo, Viswanath Urala Oct 2004

Bracing Requirements Of Cfs Cee-Studs Subjected, Perry S. Green, Thomas Sputo, Viswanath Urala

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

No abstract provided.

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An Error Analysis Of The Multirate Method For Power System Transient Stability Simulation, Jingjia Chen, Mariesa Crow, Badrul H. Chowdhury, Levent Acar Oct 2004

An Error Analysis Of The Multirate Method For Power System Transient Stability Simulation, Jingjia Chen, Mariesa Crow, Badrul H. Chowdhury, Levent Acar

Electrical and Computer Engineering Faculty Research & Creative Works

This efficient application of any numerical integration method depends on accurate estimation of the local truncation error to govern step size control. In this paper, the local truncation error of the multirate method using the forward Euler integration is derived leading to the calculation of the optimal step ratio. The techniques of applying multirate method in power systems are discussed. By implementing the multirate method in a practical power system example, the multirate strategies are proved to be efficient compared with traditional simulation methods.

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Electrical Material Property Measurements Using A Free-Field, Ultra-Wideband System [Dielectric Measurements], C. A. Grosvenor, R. Johnk, D. Novotny, S. Canales, J. Baker-Jarvis, M. Janezic, James L. Drewniak, Marina Koledintseva, Jianmin Zhang, Poorna Chander Ravva Oct 2004

Electrical Material Property Measurements Using A Free-Field, Ultra-Wideband System [Dielectric Measurements], C. A. Grosvenor, R. Johnk, D. Novotny, S. Canales, J. Baker-Jarvis, M. Janezic, James L. Drewniak, Marina Koledintseva, Jianmin Zhang, Poorna Chander Ravva

Electrical and Computer Engineering Faculty Research & Creative Works

We present nondestructive measurements of material properties using TEM horn antennas and an ultra-wideband measurement system. Time-domain gating and genetic algorithms are used to process the data and extract the dielectric properties of the material under test.

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Probabilistic Balancing Of Fault Coverage And Test Cost In Combined Built-In Self-Test/Automated Test Equipment Testing Environment, Shanrui Zhang, Minsu Choi, Nohpill Park, Fabrizio Lombardi Oct 2004

Probabilistic Balancing Of Fault Coverage And Test Cost In Combined Built-In Self-Test/Automated Test Equipment Testing Environment, Shanrui Zhang, Minsu Choi, Nohpill Park, Fabrizio Lombardi

Electrical and Computer Engineering Faculty Research & Creative Works

As design and test complexities of SoCs ever intensify, the balanced utilization of combined built-in self-test (BIST) and automated test equipment (ATE) testing becomes desirable to meet the required minimum-fault-coverage while maintaining an acceptable cost overhead. The cost associated with combined BIST/ATE testing of such systems mainly consists of 1) the cost induced by the BIST area overhead and 2) the cost induced by the overall testing time. In general, BIST is significantly faster than ATE, while it can provide only limited fault-coverage, and driving higher fault-coverage from BIST means additional area cost overhead. On the other hand, higher fault-coverage …

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Evaluating Conduction Loss Of A Parallel Igbt-Mosfet Combination, Jonathan W. Kimball, Patrick L. Chapman Oct 2004

Evaluating Conduction Loss Of A Parallel Igbt-Mosfet Combination, Jonathan W. Kimball, Patrick L. Chapman

Electrical and Computer Engineering Faculty Research & Creative Works

A variety of power devices are available to designers, each with specific advantages and limitations. For inverters, typically an IGBT combined with a p-i-n diode is used to obtain high current density. Recent developments in high-voltage MOSFETs support other alternatives. For example, a MOSFET can be paralleled with an IGBT to reduce losses at low currents, while the IGBT carries the load at high currents. The current work evaluates conduction losses in this configuration, showing applicability to generic inverters.

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Landmine Detection And Discrimination Using High-Pressure Waterjets, Daryl G. Beetner, R. Joe Stanley, Sanjeev Agarwal, Deepak R. Somasundaram, Kopal Nema, Bhargav Mantha Oct 2004

Landmine Detection And Discrimination Using High-Pressure Waterjets, Daryl G. Beetner, R. Joe Stanley, Sanjeev Agarwal, Deepak R. Somasundaram, Kopal Nema, Bhargav Mantha

Electrical and Computer Engineering Faculty Research & Creative Works

Methods of locating and identifying buried landmines using high-pressure waterjets were investigated. Methods were based on the sound produced when the waterjet strikes a buried object. Three classification techniques were studied, based on temporal, spectral, and a combination of temporal and spectral approaches using weighted density distribution functions, a maximum likelihood approach, and hidden Markov models, respectively. Methods were tested with laboratory data from low-metal content simulants and with field data from inert real landmines. Results show that the sound made when the waterjet hit a buried object could be classified with a 90% detection rate and an 18% false …

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Modeling Yield Of Carbon-Nanotube/Silicon-Nanowire Fet-Based Nanoarray Architecture With H-Hot Addressing Scheme, Shanrui Zhang, Minsu Choi, Nohpill Park Oct 2004

Modeling Yield Of Carbon-Nanotube/Silicon-Nanowire Fet-Based Nanoarray Architecture With H-Hot Addressing Scheme, Shanrui Zhang, Minsu Choi, Nohpill Park

Electrical and Computer Engineering Faculty Research & Creative Works

With molecular-scale materials, devices and fabrication techniques recently being developed, high-density computing systems in the nanometer domain emerge. An array-based nanoarchitecture has been recently proposed based on nanowires such as carbon nanotubes (CNTs) and silicon nanowires (SiNWs). High-density nanoarray-based systems consisting of nanometer-scale elements are likely to have many imperfections; thus, defect-tolerance is considered one of the most significant challenges. In this paper we propose a probabilistic yield model for the array-based nanoarchitecture. The proposed yield model can be used (1) to accurately estimate the raw and net array densities, and (2) to design and optimize more defect and fault-tolerant …

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Bulk Power System Low Frequency Oscillation Suppression By Facts/Ess, Li Zhang, Y. Liu, Michael R. Ingram, Dale T. Bradshaw, Steve Eckroad, Mariesa Crow Oct 2004

Bulk Power System Low Frequency Oscillation Suppression By Facts/Ess, Li Zhang, Y. Liu, Michael R. Ingram, Dale T. Bradshaw, Steve Eckroad, Mariesa Crow

Electrical and Computer Engineering Faculty Research & Creative Works

Low frequency oscillations in the interconnected power systems are observed all around the world. In this paper, the authors studied the inter-area mode low frequency oscillations by analyzing the phenomena in Nashville area of the Tennessee Valley Authority (TVA) system. Our study revealed 4 dynamic groups of generators in this area. Within each group, generators swing together and have the same dynamic trend. Generators from different dynamic groups swing against each other. The authors studied the possibility of using a FACTS/ESS controller to damp the low frequency oscillations in Nashville area. The active power is controlled to damp the low …

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Eaf Voltage Flicker Mitigation By Facts/Ess, Li Zhang, Yilu Liu, Michael R. Ingram, Dale T. Bradshaw, Steve Eckroad, Mariesa Crow Oct 2004

Eaf Voltage Flicker Mitigation By Facts/Ess, Li Zhang, Yilu Liu, Michael R. Ingram, Dale T. Bradshaw, Steve Eckroad, Mariesa Crow

Electrical and Computer Engineering Faculty Research & Creative Works

One of the problems caused by an electrical arc furnace (EAF) is voltage fluctuation from the variations of the active and reactive furnace load, which are known as voltage flickers. In this paper, voltage flicker mitigation results by different FACTS and energy storage systems (ESS) were presented. The system X/R ratio looking from the point of common coupling, which has a special impact on the effectiveness of active compensation, was discussed. The study has clarified the misunderstanding of how the system X/R ratio should be calculated. The study showed that FACTS with ESS could play a better role than reactive …

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Standard For Cold-Formed Steel Framing – Prescriptive Method For One And Two Family Dwellings, 2001 Edition (With 2004 Errata), American Iron And Steel Institute Sep 2004

Standard For Cold-Formed Steel Framing – Prescriptive Method For One And Two Family Dwellings, 2001 Edition (With 2004 Errata), American Iron And Steel Institute

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

No abstract provided.

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Integrated Vlsi Potentiostat For Cyclic Voltammetry In Electrolytic Reactions, Harpreet S. Narula, John G. Harris Sep 2004

Integrated Vlsi Potentiostat For Cyclic Voltammetry In Electrolytic Reactions, Harpreet S. Narula, John G. Harris

Electrical and Computer Engineering Faculty Research & Creative Works

This paper describes a CMOS integrated potentiostatic control circuit. The design maintains a constant bias potential between the reference and working electrodes for an amperometric chemical sensor. A technique of converting input currents into time for amperometric measurements is proposed. Redox currents ranging from IpA to 200nA can be measured with a maximum non-linearity of ±0.1% over this range. The design can be used to generate a cyclic voltammogram for an electrochemical reaction by sweeping the voltages across the range specified by the user. Analog inputs are processed, and digital outputs are generated without requiring a power-hungry A/D converter. A …

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Solvent And Method For Extraction Of Triglyceride Rich Oil, Shubhender Kapila, Paul Ki-Souk Nam, V. J. Flanigan Sep 2004

Solvent And Method For Extraction Of Triglyceride Rich Oil, Shubhender Kapila, Paul Ki-Souk Nam, V. J. Flanigan

Chemistry Faculty Research & Creative Works

The present invention relates to a solvent for use in extracting oil from an oil bearing material, such as soybeans, with the solvent resulting in the selective extraction of a triglyceride rich oil, which contains 95% or greater triglycerides and non-polar constituents, with the solvent comprised of a hydrocarbon, preferably hexane, and a fluorocarbon, so that the solvent has a viscosity less than 2.6 centipoise and a polarity of less than 0.1. The present invention also relates to a method of using the solvent to extract the triglyceride rich oil, with the method including preferably extracting the oil at a …

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Experimental And Theoretical Investigation Of Mixing In A Bottom Gas-Stirred Ladle, Jun Aoki, Brian G. Thomas, Jörg Peter, Kent D. Peaslee Sep 2004

Experimental And Theoretical Investigation Of Mixing In A Bottom Gas-Stirred Ladle, Jun Aoki, Brian G. Thomas, Jörg Peter, Kent D. Peaslee

Materials Science and Engineering Faculty Research & Creative Works

No abstract provided.

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Defect Chemistry Of Mixed Ionic/Electronic P-Type Oxides, Harlan U. Anderson, Xiao-Dong Zhou, Fatih Dogan Sep 2004

Defect Chemistry Of Mixed Ionic/Electronic P-Type Oxides, Harlan U. Anderson, Xiao-Dong Zhou, Fatih Dogan

Materials Science and Engineering Faculty Research & Creative Works

The p-type perovskite structure oxides are finding use in a number of energy related applications. In particular they are being used as cathodes in fuel cells as well as dense oxygen separation membranes. The defect concentration and defect mobility determine the electrical properties. Since both of these are dependent upon the operating temperature and oxygen activity, it is important to understand how an oxide equilibrates with its environment. In this paper, a defect chemistry model for the oxidation-reduction behavior of p-type perovskites is reviewed with formulations in the (La,Sr)(Cr,Mn,Co,Fe)03 system being used as examples.

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Anode Supported Single Chamber Solid Oxide Fuel Cell In Ch 4 -Air Mixture, Toshio Suzuki, Piotr Jasinski, Vladimir Petrovsky, Harlan U. Anderson, Fatih Dogan Sep 2004

Anode Supported Single Chamber Solid Oxide Fuel Cell In Ch 4 -Air Mixture, Toshio Suzuki, Piotr Jasinski, Vladimir Petrovsky, Harlan U. Anderson, Fatih Dogan

Materials Science and Engineering Faculty Research & Creative Works

In this study, yttrium-stabilized zirconia (YSZ) thin films 1-2 μm thick electrolyte have been prepared using NiO-YSZ anode as substrates. Fuel cell test was conducted with the single chamber configuration in methane-air gas mixture using (la,Sr)(Co,Fe) O3 (LSCF) as the cathode. Test results showed that the open-circuit voltage to be >0.8 V, with power density as high as 0.12 W cm−2. It was also shown that gas flow rate has a large influence on the performance of the fuel cell, which indicates the importance of the geometrical design for anode support fuel cell system.

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Exploiting Independent Filter Bandwidth Of Human Factor Cepstral Coefficients In Automatic Speech Recognition, Mark D. Skowronski, John G. Harris Sep 2004

Exploiting Independent Filter Bandwidth Of Human Factor Cepstral Coefficients In Automatic Speech Recognition, Mark D. Skowronski, John G. Harris

Electrical and Computer Engineering Faculty Research & Creative Works

Mel frequency cepstral coefficients (MFCC) are the most widely used speech features in automatic speech recognition systems, primarily because the coefficients fit well with the assumptions used in hidden Markov models and because of the superior noise robustness of MFCC over alternative feature sets such as linear prediction-based coefficients. The authors have recently introduced human factor cepstral coefficients (HFCC), a modification of MFCC that uses the known relationship between center frequency and critical bandwidth from human psychoacoustics to decouple filter bandwidth from filter spacing. In this work, the authors introduce a variation of HFCC called HFCC-E in which filter bandwidth …

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Low-Input-Voltage, Low-Power Boost Converter Design Issues, Jonathan W. Kimball, Theresa L. Flowers, Patrick L. Chapman Sep 2004

Low-Input-Voltage, Low-Power Boost Converter Design Issues, Jonathan W. Kimball, Theresa L. Flowers, Patrick L. Chapman

Electrical and Computer Engineering Faculty Research & Creative Works

Issues associated with boost converter design and performance are investigated when a low input voltage is used. Low-input-voltage sources include single fuel cells, single solar cells, and thermoelectric devices. The primary context is interfacing single micro fuel cells to portable electronic loads, such as mobile phones. Efficiency and circuit startup are the two most difficult issues for a low-cost design. It is shown in theory and experiment that the boost converter has a voltage collapse point. A simple startup technique is proposed that is appropriate for some applications.

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Multi-Class Cancer Classification By Semi-Supervised Ellipsoid Artmap With Gene Expression Data, Rui Xu, Donald C. Wunsch, Georgios C. Anagnostopoulos Sep 2004

Multi-Class Cancer Classification By Semi-Supervised Ellipsoid Artmap With Gene Expression Data, Rui Xu, Donald C. Wunsch, Georgios C. Anagnostopoulos

Electrical and Computer Engineering Faculty Research & Creative Works

To accurately identify the site of origin of a tumor is crucial to cancer diagnosis and treatment. With the emergence of DNA microarray technologies, constructing gene expression profiles for different cancer types has already become a promising means for cancer classification. In addition to binary classification, the discrimination of multiple tumor types is also important semi-supervised ellipsoid ARTMAP (ssEAM) is a novel neural network architecture rooted in adaptive resonance theory suitable for classification tasks. ssEAM can achieve fast, stable and finite learning and create hyper-ellipsoidal clusters inducing complex nonlinear decision boundaries. Here, we demonstrate the capability of ssEAM to discriminate …

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