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Articles 13981 - 14010 of 21750

Full-Text Articles in Engineering

Comparison Of Text-Dependent Speaker Identification Methods For Short Distance Telephone Lines Using Artificial Neural Networks, Ganesh K. Venayagamoorthy, N. Sundepersadh Jan 2000

Comparison Of Text-Dependent Speaker Identification Methods For Short Distance Telephone Lines Using Artificial Neural Networks, Ganesh K. Venayagamoorthy, N. Sundepersadh

Electrical and Computer Engineering Faculty Research & Creative Works

The transition to democracy in South Africa has brought with it certain challenges. The main challenge is to get rid of crime and corruption. The paper presents a technique to combat white-collar crime in telephone transactions by identifying and verifying speakers using artificial neural networks (ANNs). Results are presented to show that speaker identification is feasible and this is illustrated with two different types of ANN architectures and with two different types of characteristic features as inputs to ANNs.

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Successful Proposal Preparation, Mariesa Crow Jan 2000

Successful Proposal Preparation, Mariesa Crow

Electrical and Computer Engineering Faculty Research & Creative Works

No abstract provided.

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About Resonant Modes At The Shielded Dielectric Hemisphere, Sergey Kharkovsky, A. E. Kogut, Z. E. Eremenko, V. V. Kutuzov, Yuri F. Filipov Jan 2000

About Resonant Modes At The Shielded Dielectric Hemisphere, Sergey Kharkovsky, A. E. Kogut, Z. E. Eremenko, V. V. Kutuzov, Yuri F. Filipov

Electrical and Computer Engineering Faculty Research & Creative Works

The resonant modes, which are excited at the shielded dielectric hemisphere, are investigated by the theoretical and experimental methods. The low-Q-factor modes of air cavity and high-Q-factor whispering gallery modes of dielectric structure are existed together in the case of high radial index value. The Q-factor value of the whispering gallery modes of the shielded dielectric sphere with the certain correlation between the sizes of dielectric hemisphere and metal shield can be more great than the Q-factor of the whispering gallery modes of the similar open dielectric resonator.

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A Hysteresis Current-Regulated Control For Multi-Level Drives, Keith Corzine Jan 2000

A Hysteresis Current-Regulated Control For Multi-Level Drives, Keith Corzine

Electrical and Computer Engineering Faculty Research & Creative Works

Most multi-level converters are controlled through the use of voltage-source based control techniques such as space-vector modulation or multi-level sine-triangle modulation. However, in many applications such as field oriented drives, a high bandwidth current-source inverter based control is more desirable. In this paper, the concept of a multi-level hysteresis current-source control is set forth. The new control is experimentally verified using a four-level converter/induction motor drive system and the results are compared to a space vector modulation controller. A dynamic study involving a step change in current command demonstrates the controls high bandwidth.

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A Robust Proportionate Affine Projection Algorithm For Network Echo Cancellation, T. Gansler, J. Benesty, Steven L. Grant, M. M. Sondhi Jan 2000

A Robust Proportionate Affine Projection Algorithm For Network Echo Cancellation, T. Gansler, J. Benesty, Steven L. Grant, M. M. Sondhi

Electrical and Computer Engineering Faculty Research & Creative Works

Echo cancelers which cover longer impulse responses (greater than or equal to 64 ms) are desirable. Long responses create a need for more rapidly converging algorithms in order to meet the specifications for network echo cancelers devised by the ITU (International Telecommunication Union). In general, faster convergence implies a higher sensitivity to near-end disturbances, especially "double-talk." Previously, a fast converging algorithm called the proportionate NLMS (normalized least mean squares) algorithm (PNLMS) has been proposed. This algorithm exploits the sparseness of the echo path in order to increase the convergence rate. A robust version of PNLMS has also been presented which …

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Drawbacks Of The Dissolution Method For Measurement Of The Liquid-Solid Mass-Transfer Coefficients In Two-Phase Flow Packed-Bed Reactors Operated At Low And High Pressures, Muthanna H. Al-Dahhan, Wes Highfill, Boon Tee Ong Jan 2000

Drawbacks Of The Dissolution Method For Measurement Of The Liquid-Solid Mass-Transfer Coefficients In Two-Phase Flow Packed-Bed Reactors Operated At Low And High Pressures, Muthanna H. Al-Dahhan, Wes Highfill, Boon Tee Ong

Chemical and Biochemical Engineering Faculty Research & Creative Works

The Dissolution Method Was Used Predominantly at Atmospheric Conditions to Measure the Liquid-Solid Mass-Transfer Coefficient in Two-Phase Flow Packed-Bed Reactors. in an Attempt to Investigate the Effect of Reactor Pressure and Gas Flow Rate on the Liquid-Solid Mass-Transfer Coefficient in a Trickle-Bed Reactor using the Dissolution Method, Difficulties Were Encountered in Implementing This Method at Low- to High-Pressure Operation. Noticeable Losses in the Dissolved Material Were Observed as a Result of Flashing/stripping from the Liquid Phase to the Atmosphere and the Effluent Gas Stream. This Leads to Misinterpretation of the Effect of Reactor Pressure and to Improper Conclusions. in This …

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Discriminating Trickle-Flow Hydrodynamic Models: Some Recommendations, F. Larachi, I. Iliuta, M. (Muthanna) H. Al-Dahhan, M. P. Dudukovic Jan 2000

Discriminating Trickle-Flow Hydrodynamic Models: Some Recommendations, F. Larachi, I. Iliuta, M. (Muthanna) H. Al-Dahhan, M. P. Dudukovic

Chemical and Biochemical Engineering Faculty Research & Creative Works

The Forecasting Ability of Five One-Dimensional (1-D) Two-Fluid Phenomenological Models for Liquid Holdup and Two-Phase Pressure Drop in Trickle-Flow Reactors Was Evaluated using the Most Comprehensive Trickle-Flow Regime Database. All of These Models, Namely, the Permeability Model, the Slit Model, the Extended Slit Model, the 1-D CFD Model, and the Double-Slit Model Can Be Used to Predict Liquid Holdup. among Them, the Permeability and the Slit Models, Because of a Much Simpler Structure, Are Recommended. the Extended Slit Model based on Iliuta Et Al. (Ind. Eng. Chem. Res. 1998, 37, 4542) Shear and Slip Constitutive Relationships Can Be Employed for …

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Double-Slit Model For Partially Wetted Trickle Flow Hydrodynamics, I. Iliuta, F. Larachi, M. (Muthanna) H. Al-Dahhan Jan 2000

Double-Slit Model For Partially Wetted Trickle Flow Hydrodynamics, I. Iliuta, F. Larachi, M. (Muthanna) H. Al-Dahhan

Chemical and Biochemical Engineering Faculty Research & Creative Works

A Double-Slit Model Developed Can Predict the Frictional Two-Phase Pressure Drop, External Liquid Holdup, Pellet-Scale External Wetting Efficiency, and Gas - Liquid Interfacial Area in Cocurrent Downflow Trickle-Bed Reactors Operated under Partially Wetted Conditions in the Trickle Flow Regime. the Model, an Extension of the Holub Et Al. (1992, 1993) Mechanistic Pore-Scale Phenomenological Approach, Was Designed to Mimic the Actual Bed Void by Two Inclined and Interconnected Slits: Wet and Dry Slit. the External Wetting Efficiency is Linked to Both the Pressure Drop and External Liquid Holdup. the Model Also Predicts Gas - Liquid Interfacial Areas in Partially Wetted Conditions. …

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Applicability Of Ozone In Small Drinking Water Systems, Craig D. Adams, Justin Sutherland Jan 2000

Applicability Of Ozone In Small Drinking Water Systems, Craig D. Adams, Justin Sutherland

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

The use of ozone in water treatment plants is expanding rapidly in the United States. Ozone offers excellent disinfection properties (including chlorine-resistant pathogens) and does not form trihalomethanes. Additionally, ozone can be used to achieve or control many other water quality parameters such as color, taste and odor, and inorganic and organic contaminant concentrations. Control of ozone's disinfection byproducts such as bromate (formed in high bromide waters) is required. This presentation will review the synergistic effects of ozone applicable to use in small water treatment plants.

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Accumulation Of Heavy Metals By Vegetables Grown In Mine Wastes, George P. Cobb, Kristin Sands, Melissa Waters, Bobby G. Wixson, Elaine Dorward-King Jan 2000

Accumulation Of Heavy Metals By Vegetables Grown In Mine Wastes, George P. Cobb, Kristin Sands, Melissa Waters, Bobby G. Wixson, Elaine Dorward-King

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

Lead, cadmium, arsenic, and zinc were quantified in mine wastes and in soils mixed with mine wastes. Metal concentrations were found to be heterogeneous in the wastes. Iceberg lettuce, Cherry Belle radishes, Roma bush beans, and Better Boy tomatoes were cultivated in mine wastes and in waste-amended soils. Lettuce and radishes had 100% survival in the 100% mine waste treatments compared to 0% and 25% survival for tomatoes and beans, respectively. Metal concentrations were determined in plant tissues to determine uptake and distribution of metals in the edible plant parts. Individual soil samples were collected beneath each plant to assess …

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Ethics Exercises For Civil, Environmental, And Geological Engineers, Paul Michael Santi Jan 2000

Ethics Exercises For Civil, Environmental, And Geological Engineers, Paul Michael Santi

Geosciences and Geological and Petroleum Engineering Faculty Research & Creative Works

The practices of civil, environmental, and geological engineering share many common ethical dilemmas. These fields typically require extensive interaction with clients and regulatory agencies, while dealing with unpredictable earth materials for design and uncertain design parameters. Consequently, a capstone design course must address not only technical issues, but also a wide range of ethical and behavioral issues. This study presents a series of exercises used in the classroom to teach these issues through dealing with "gray" ethical areas, concepts of advocacy and the use of compromise, relating specific stories to global concepts, proper behavior in the corporate environment, and the …

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Plastic Manufacturing Process Selection Methodology Using Self-Organizing Map (Som)/Fuzzy Analysis, R. Raviwongse, Venkat Allada, T. Sandidge Jan 2000

Plastic Manufacturing Process Selection Methodology Using Self-Organizing Map (Som)/Fuzzy Analysis, R. Raviwongse, Venkat Allada, T. Sandidge

Engineering Management and Systems Engineering Faculty Research & Creative Works

For plastic products, one of the crucial decisions made during the preliminary design stage is the selection of an appropriate manufacturing process. In many industries, the selection of the manufacturing process is primarily based on the empirical knowledge and past experience of the manufacturing personnel. This selection procedure may result in inconsistent or poor choices if the manufacturing personnel fail to map correctly the product characteristics with the manufacturing efficacy of various manufacturing processes. This paper presents an intelligent self-organizing map (SOM)/fuzzy-based model to aid designers in the selection of an appropriate plastic manufacturing process. The plastic part attributes are …

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Fourier Based Three Phase Power Metering System, Scott C. Smith, M. J. Devaney Jan 2000

Fourier Based Three Phase Power Metering System, Scott C. Smith, M. J. Devaney

Electrical and Computer Engineering Faculty Research & Creative Works

The increased application of higher frequency nonlinear loads, such as electronic fluorescent ballasts and higher speed adjustable drives, has resulted in the need to monitor the higher power system harmonics which were largely ignored in earlier power monitors. Addressing this need requires a meter with substantially higher sample rate and greater computational power. This paper describes a zero-blind, three-phase, three-element power meter that samples three voltages and four currents at 256 points per cycle. The instrument relies on the FFT to compute real and reactive power at each harmonic and reports total real, reactive, and distortion power on each phase. …

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Border Detection On Digitized Skin Tumor Images, Z. Zhang, William V. Stoecker, Randy Hays Moss Jan 2000

Border Detection On Digitized Skin Tumor Images, Z. Zhang, William V. Stoecker, Randy Hays Moss

Chemistry Faculty Research & Creative Works

A radial search technique is presented for detecting skin tumor borders in clinical dermatology images. First, it includes two rounds of radial search based on the same tumor center. The first-round search is independent, and the second-round search is knowledge-based tracking. Then a rescan with a new center is used to solve the blind-spot problem. The algorithm is tested on model images with excellent performance, and on 300 real clinical images with a satisfactory result

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The Influence Of Poly(Acrylic Acid) Molar Mass On The Properties Of Polyalkenoate Cements Formed From Zinc Oxide/Apatite Mixtures, Sinead Kenny, Robert G. Hill, Mark R. Towler Jan 2000

The Influence Of Poly(Acrylic Acid) Molar Mass On The Properties Of Polyalkenoate Cements Formed From Zinc Oxide/Apatite Mixtures, Sinead Kenny, Robert G. Hill, Mark R. Towler

Chemical and Biochemical Engineering Faculty Research & Creative Works

The influence of poly (acrylic acid) molar mass was investigated on cements formed from zinc oxide-apatite mixtures at three aging times: one, seven and 28 days. Cements based on both hydroxyapatite and fluorapatite were investigated. The compressive strength, un-notched fracture strength and fracture toughness increased markedly with poly (acrylic acid) molar mass. The fracture toughness and un-notched fracture strength increased with aging time for the two highest molar mass cements but decreased with time for the two lowest molar mass cements. The greater chain entanglement density present in the higher molar mass cements is thought to contribute significantly to the …

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Adaptive Critic Based Neurocontroller For Turbogenerators With Global Dual Heuristic Programming, Ganesh K. Venayagamoorthy, Donald C. Wunsch, Ronald G. Harley Jan 2000

Adaptive Critic Based Neurocontroller For Turbogenerators With Global Dual Heuristic Programming, Ganesh K. Venayagamoorthy, Donald C. Wunsch, Ronald G. Harley

Electrical and Computer Engineering Faculty Research & Creative Works

Turbogenerators are nonlinear time varying systems. This paper presents the design of a neurocontroller for such a turbogenerator that augments/replaces the traditional automatic voltage regulator (AVR) and the turbine governor using a novel technique based on the adaptive critic designs (ACDs) with emphasis on global dual heuristic programming (GDHP). Simulation results are presented to show that the neurocontroller derived with the GDHP approach is robust and its performance is better when compared with that derived with other neural network technique, especially when system conditions and configuration changes.

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Advances Of Gyromagnetic Electronics For Emc Problems, Marina Koledintseva, L. K. Mikhailovsky, Alexander A. Kitaytsev Jan 2000

Advances Of Gyromagnetic Electronics For Emc Problems, Marina Koledintseva, L. K. Mikhailovsky, Alexander A. Kitaytsev

Electrical and Computer Engineering Faculty Research & Creative Works

A number of EMC problems at microwaves-detection and measurement of power (spectrum) of the signals and suppression of unwanted radiation-can be solved owing to the results obtained in the field of gyromagnetic (spin) electronics. The latter deals with the unique properties of gyromagnetic media (GM) based on microwave ferrites, including high-anisotropy hexagonal ferrites that do not need an intense magnetization field for their operation at ferromagnetic resonance. Approaches to the study of the interaction of GM with an electromagnetic field and ways of modeling frequency-selective measuring devices, absorbing coatings and all-mode filters of harmonics on the basis of GM are …

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Analysis Of A Novel Four-Level Dc/Dc Boost Converter, Keith Corzine, Sonal K. Majeethia Jan 2000

Analysis Of A Novel Four-Level Dc/Dc Boost Converter, Keith Corzine, Sonal K. Majeethia

Electrical and Computer Engineering Faculty Research & Creative Works

In this paper, novel two-quadrant buck/boost and one-quadrant boost four-level DC/DC power converters are introduced. The primary application for these converters is that of interfacing a low-voltage DC source, such as a fuel cell or battery, to a high-voltage four-level inverter. One important feature of the four-level DC/DC power converters proposed is the ability to perform the power conversion and balance the inverter capacitor voltages simultaneously. With the capacitor voltage balancing, it is possible to obtain the full voltage from the inverter. For the boost converter, the steady-state and nonlinear average-value (NLAM) models are developed. The NLAM is verified against …

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Control Of Statcom With Energy Storage Device, Chen Shen, Zhiping Yang, Stan Atcitty, Mariesa Crow Jan 2000

Control Of Statcom With Energy Storage Device, Chen Shen, Zhiping Yang, Stan Atcitty, Mariesa Crow

Electrical and Computer Engineering Faculty Research & Creative Works

In this paper, the control method of a STATCOM with an energy storage device is discussed. To determine the switching level control, UPWM (unique pulse width modulation) and SPWM (sinusoidal pulse width modulation) methods are compared. A linearized model of a STATCOM with a battery is set up to derive monitoring level control strategies. All the control methods are verified by the PSCAD/EMTDC software package.

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Power Education At The Crossroads, Badrul H. Chowdhury Jan 2000

Power Education At The Crossroads, Badrul H. Chowdhury

Electrical and Computer Engineering Faculty Research & Creative Works

To meet the demands of designing and running far more complex and highly integrated electricity systems, a new kind of power engineer is needed. In this paper, the author describes how, though students tend to favor higher-tech and more lucrative fields than power Engineering; reports of the discipline''s demise are exaggerated

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Modeling And Simulation Of The Dynamic Behavior Of Monoliths: Effects Of Pore Structure From Pore Network Model Analysis And Comparison With Columns Packed With Porous Spherical Particles, Athanasios I. Liapis, J. J. Meyers, Orrin K. Crosser Dec 1999

Modeling And Simulation Of The Dynamic Behavior Of Monoliths: Effects Of Pore Structure From Pore Network Model Analysis And Comparison With Columns Packed With Porous Spherical Particles, Athanasios I. Liapis, J. J. Meyers, Orrin K. Crosser

Chemical and Biochemical Engineering Faculty Research & Creative Works

A mathematical model is presented that could be used to describe the dynamic behavior, scale-up, and design of monoliths involving the adsorption of a solute of interest. The value of the pore diffusivity of the solute in the pores of the skeletons of the monolith is determined in an a priori manner by employing the pore network modeling theory of Meyers and Liapis [J. Chromatogr. A, 827 (1998) 197 and 852 (1999) 3]. The results clearly show that the pore diffusion coefficient, D(mp), of the solute depends on both the pore size distribution and the pore connectivity, n(T), of the …

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Investigation Of Inflection Points As Brace Points In Multi-Span Purlin Roof Systems, Michael R. Bryant, Thomas M. Murray Dec 1999

Investigation Of Inflection Points As Brace Points In Multi-Span Purlin Roof Systems, Michael R. Bryant, Thomas M. Murray

CCFSS Library (1939 - present)

No abstract provided.

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Analysis And Average-Value Modeling Of An Inductorless Synchronous Machine Load Commutated Converter System, J. T. Alt, Scott D. Sudhoff, B. E. Ladd Dec 1999

Analysis And Average-Value Modeling Of An Inductorless Synchronous Machine Load Commutated Converter System, J. T. Alt, Scott D. Sudhoff, B. E. Ladd

Electrical and Computer Engineering Faculty Research & Creative Works

Synchronous machine fed load-commutated converters (SMLCCs) are commonly used for dc power sources in marine and aircraft power systems. The focus of this paper is to set forth a model for SMLCCs for use in transient stability studies involving these systems. Although there has been considerable work in this area, much of this work has assumed the existence of a dc link inductor whereupon the dc link current is approximately constant. In practice, this filter is often eliminated, whereupon previous models are no longer valid. A new average-value model is set forth for SMLCCs in which there is no dc …

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An Accurate Method Of Neglecting Dynamic Saliency Of Synchronous Machines In Power Electronic Based Systems, Steven Pekarek, E. A. Walters Dec 1999

An Accurate Method Of Neglecting Dynamic Saliency Of Synchronous Machines In Power Electronic Based Systems, Steven Pekarek, E. A. Walters

Electrical and Computer Engineering Faculty Research & Creative Works

In this paper, motivations for neglecting dynamic saliency in the detailed models of power electronic based systems are presented, A new method of neglecting dynamic saliency is then introduced in which approximate operational impedances are derived from original dynamic salient models. New machine parameters are obtained by fitting to the approximate impedance curves, yielding model parameters in which dynamic saliency is eliminated. An example synchronous machine/converter system is provided that demonstrates the accuracy and increased simulation efficiency resulting from this technique. Therein, errors resulting from neglecting dynamic saliency are reduced from greater than 25% using traditional approximations to less than …

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Multimode Solution For The Reflection Properties Of An Open-Ended Rectangular Waveguide Radiating Into A Dielectric Half-Space: The Forward And Inverse Problems, R. Zoughi, Aaron D. Benally, Karl Joseph Bois Dec 1999

Multimode Solution For The Reflection Properties Of An Open-Ended Rectangular Waveguide Radiating Into A Dielectric Half-Space: The Forward And Inverse Problems, R. Zoughi, Aaron D. Benally, Karl Joseph Bois

Electrical and Computer Engineering Faculty Research & Creative Works

Open-ended rectangular waveguides are extensively used in nondestructive dielectric material evaluation. The dielectric properties of an infinite-half space of a material are calculated from the measured reflection properties referenced to the waveguide aperture. This calculation relies on a theoretical and numerical derivation of the reflection coefficient likewise referenced to the waveguide aperture. Most of these derivations assume the dominant mode field distribution across the waveguide aperture. However, when dealing with low permittivity and low loss dielectric materials, there may exist significant errors when calculating the dielectric properties from the measured reflection coefficient. These errors have also shown to be more …

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Multimedia Databases, S. R. Subramanya Dec 1999

Multimedia Databases, S. R. Subramanya

Electrical and Computer Engineering Faculty Research & Creative Works

The acquisition, generation, storage and processing of multimedia data in computers and transmission over networks have grown tremendously. Databases have been developed to cope with huge amounts of data in different applications. Multimedia databases (MMDB) are essential for efficient management and effective use of this data. They are however still in their infancy. Most current MMDB system prototypes are closely bound to narrow application areas. Experiences gained from developing and using novel multimedia will help advance the multimedia database technology.

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An Efficient And Accurate Method Of Representing Magnetic Saturation In Physical-Variable Models Of Synchronous Machines, Steven Pekarek, E. A. Walters, B. T. Kuhn Dec 1999

An Efficient And Accurate Method Of Representing Magnetic Saturation In Physical-Variable Models Of Synchronous Machines, Steven Pekarek, E. A. Walters, B. T. Kuhn

Electrical and Computer Engineering Faculty Research & Creative Works

When analyzing machine/converter systems it is convenient to represent the stator variables in physical (abc) form. It has recently been shown that a physical-variable voltage-behind-reactance form of the synchronous machine model can be derived which is numerically more efficient than existing physical-variable models. In this research, a new voltage-behind-reactance model is derived which incorporates the effects of magnetic saturation. This model is shown to have the same numerical efficiency of the unsaturated model and is readily implemented in either circuit-based or differential-equation based simulation languages. An example system is provided which demonstrates the accuracy and efficiency of this model for …

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Economic Dispatch And Optimal Sizing Of Battery Energy Storage Systems In Utility Load-Leveling Operations, Chin H. Lo, Max Darwin Anderson Dec 1999

Economic Dispatch And Optimal Sizing Of Battery Energy Storage Systems In Utility Load-Leveling Operations, Chin H. Lo, Max Darwin Anderson

Electrical and Computer Engineering Faculty Research & Creative Works

Battery energy storage (BES) systems show promise of savings for both the utility and the customer. An algorithm combining multi-pass dynamic programming (MPDP) with a time-shift technique has been developed for two purposes: economic dispatch of BES and finding optimal BES power and energy capacities in a power system. Due to the daily cyclic nature of the load curve, a 168-hour load curve is decomposed into seven 24-hour subsections for easy management. Each subsection is treated independently. Decomposition can save computation time and computer memory. A time-shift technique provides better starting state values and improves the finding process of the …

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Dielectric Plug-Loaded Two-Port Transmission Line Measurement Technique For Dielectric Property Characterization Of Granular And Liquid Materials, K. Mubarak, R. Zoughi, Aaron D. Benally, Karl Joseph Bois, Larry F. Handjojo Dec 1999

Dielectric Plug-Loaded Two-Port Transmission Line Measurement Technique For Dielectric Property Characterization Of Granular And Liquid Materials, K. Mubarak, R. Zoughi, Aaron D. Benally, Karl Joseph Bois, Larry F. Handjojo

Electrical and Computer Engineering Faculty Research & Creative Works

There are numerous dielectric property characterization techniques available in the microwave regime each with its own uniqueness, advantages and disadvantages. The two-port completely-filled waveguide (transmission line) technique is a robust measurement approach which is well suited for solid dielectric materials. In this case, the dielectric material can be relatively easily machined to fit inside the waveguide and the subsequent measurement of the scattering parameters of this two-port device renders the dielectric properties of the material filling the waveguide. However, this technique is not well suited for measuring the dielectric properties of granular and liquid materials. These materials are used in …

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Wide-Bandwidth Multi-Resolutional Analysis Of A Surface-Mounted Pm Synchronous Machine, S. D. Sudhoff, Jerry L. Tichenor, James L. Drewniak Dec 1999

Wide-Bandwidth Multi-Resolutional Analysis Of A Surface-Mounted Pm Synchronous Machine, S. D. Sudhoff, Jerry L. Tichenor, James L. Drewniak

Electrical and Computer Engineering Faculty Research & Creative Works

Advances in power semiconductor devices have led to inverters with unprecedented voltage edge rates. This has decreased inverter switching losses and enabled the use of increasingly higher switching frequencies. However, faster edge rates and higher switching frequencies increase electromagnetic compatibility (EMC) problems, machine insulation stress, bearing currents, and other aspects of system design. Typical computer simulations used to design and evaluate proposed electric drive systems cannot be used to predict these high-frequency effects. A wide-bandwidth multi-resolutional analysis that allows designers to anticipate and quantify high-frequency effects is detailed in this paper. The approach is specifically applied to permanent magnet synchronous …

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