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Theoretical And Practical Requirements For A System Of Pre-Design Analysis, Andrew S. Gibbons, Jon S. Nelson, Robert E. Richards Aug 1999

Theoretical And Practical Requirements For A System Of Pre-Design Analysis, Andrew S. Gibbons, Jon S. Nelson, Robert E. Richards

Faculty Publications

This research is aimed at bridging the worlds of simulation design as practiced by computer scientists and systems engineers and instructional design as practiced by a multitude of corporate, government, and military instructional designers, most of whom lack formal schooling in the techniques of either area.

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Nonlinear Robust Missile Autopilot Design Using Successive Galerkin Approximation, Timothy Mclain, Randal W. Beard Aug 1999

Nonlinear Robust Missile Autopilot Design Using Successive Galerkin Approximation, Timothy Mclain, Randal W. Beard

Faculty Publications

The application of a new nonlinear robust control strategy to the design of missile autopilots is presented. The control approach described and demonstrated here is based upon the numerical solution of the Hamilton-Jacobi-Isaacs equation by Successive Galerkin Approximation. Using this approach, feedback controllers are computed by an iterative application of a numerical Galerkin-type PDE solver. Application of this approach to the design of a pitch-axis autopilot for a missile having uncertain pitch moment and lift force is described.

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Field Observations On The Myrmecophilous Beetle Araeoschizus Airmeti Tanner (Coleoptera: Tenebrionidae) At Harvester Ant (Hymenoptera: Formicidae) Mounds, Paul Hendricks, Lisa M. Hendricks Jul 1999

Field Observations On The Myrmecophilous Beetle Araeoschizus Airmeti Tanner (Coleoptera: Tenebrionidae) At Harvester Ant (Hymenoptera: Formicidae) Mounds, Paul Hendricks, Lisa M. Hendricks

Great Basin Naturalist

No abstract provided.

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Characteristics Of Natal And Non-Natal Kit Fox Dens In The Northern Chihuahuan Desert, Penny J. Rodrick, Nancy E. Mathews Jul 1999

Characteristics Of Natal And Non-Natal Kit Fox Dens In The Northern Chihuahuan Desert, Penny J. Rodrick, Nancy E. Mathews

Great Basin Naturalist

We studied kit fox den characteristics of the northern McGregor Range of Fort Bliss Military Reservation, New Mexico, during 1994 and 1995. Twenty radio-collared kit foxes used 132 different dens, including 16 natal dens. Kit fox dens were located primarily in creosote-dominated habitat found in relatively flat, well-drained terrain. Natal dens were virtually indistinguishable from non-natal dens; however, natal den entrances were taller than non-natal den entrances. Entrances found at all dens were oriented more frequently toward the northwest and southeast. Kit foxes used more new dens during the breeding (January–February) and pup-rearing season (May–July) than during gestation.

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A Neural Model Of Centered Tri-Gram Speech Recognition, Tony R. Martinez, Dan A. Ventura, D. Randall Wilson, Brian Moncur Jul 1999

A Neural Model Of Centered Tri-Gram Speech Recognition, Tony R. Martinez, Dan A. Ventura, D. Randall Wilson, Brian Moncur

Faculty Publications

A relaxation network model that includes higher order weight connections is introduced. To demonstrate its utility, the model is applied to the speech recognition domain. Traditional speech recognition systems typically consider only that context preceding the word to be recognized. However, intuition suggests that considering both preceding context as well as following context should improve recognition accuracy. The work described here tests this hypothesis by applying the higher order relaxation network to consider both precedes and follows context in speech recognition. The results demonstrate both the general utility of the higher order relaxation network as well as its improvement over …

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Combining Cross-Validation And Confidence To Measure Fitness, Tony R. Martinez, D. Randall Wilson Jul 1999

Combining Cross-Validation And Confidence To Measure Fitness, Tony R. Martinez, D. Randall Wilson

Faculty Publications

Neural network and machine learning algorithms often have parameters that must be tuned for good performance on a particular task. Leave-one-out cross-validation (LCV) accuracy is often used to measure the fitness of a set of parameter values. However, small changes in parameters often have no effect on LCV accuracy. Many learning algorithms can measure the confidence of a classification decision, but often confidence alone is an inappropriate measure of fitness. This paper proposes a combined measure of Cross- Validation and Confidence (CVC) for obtaining a continuous measure of fitness for sets of parameters in learning algorithms. This paper also proposes …

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The First Mormon Temple: Design, Construction, And Historic Context Of The Kirtland Temple Elwin C. Robison, Paul L. Anderson Jul 1999

The First Mormon Temple: Design, Construction, And Historic Context Of The Kirtland Temple Elwin C. Robison, Paul L. Anderson

BYU Studies

Elwin C. Robison. The First Mormon Temple: Design, Construction, and Historic Context of the Kirtland Temple. Provo, Utah: Brigham Young University Press, 1997. xv; 216 pp. Illustrations, index, $21.95.

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Successive Galerkin Approximation Of The Isaacs Equation, Timothy Mclain, Randal W. Beard, John T. Wen Jul 1999

Successive Galerkin Approximation Of The Isaacs Equation, Timothy Mclain, Randal W. Beard, John T. Wen

Faculty Publications

The successive Galerkin approximation (SGA) algorithm has recently been developed for approximating solutions to the Hamilton-Jacobi-Isaacs equation. The algorithm produces feedback control laws that are stabilizing on a well-defined region of state space. The objective of this paper is to demonstrate the application of the SGA algorithm to two simple examples. The examples serve several purposes: first they illustrate how the algorithm is applied in a setting that is simple enough to write out in detail, second they demonstrate the convergence of the algorithm in a setting where the actual solution can be derived analytically.

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Successive Galerkin Approximation Of A Nonlinear Optimal Attitude Control, Timothy Mclain, Randal W. Beard, Johnathan Lawton Jun 1999

Successive Galerkin Approximation Of A Nonlinear Optimal Attitude Control, Timothy Mclain, Randal W. Beard, Johnathan Lawton

Faculty Publications

This paper presents the application of the successive Galerkin approximation (SGA) to the Hamilton-Jacobi-Bellman equation to obtain solutions of the optimal attitude control problem. Galerkin's method approximates the value function by a truncated Galerkin series expansion. To do so, a truncated Galerkin basis set is formed. A sufficient number of functions must be included in this Galerkin basis set in order to guarantee that the solution will be a stabilizing control. By increasing the size of the Galerkin basis the quality of the approximation is improved at the cost of rapid growth in the computation load of the SGA. A …

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Committee Activities, Lynne Kutsukake, Sachie Noguchi Jun 1999

Committee Activities, Lynne Kutsukake, Sachie Noguchi

Journal of East Asian Libraries

No abstract provided.

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Synthesis And Experimental Testing Of A Nonlinear Optimal Tracking Controller, Timothy Mclain, Randal W. Beard, Christopher A. Bailey Jun 1999

Synthesis And Experimental Testing Of A Nonlinear Optimal Tracking Controller, Timothy Mclain, Randal W. Beard, Christopher A. Bailey

Faculty Publications

This paper presents a novel approach for developing tracking controllers for nonlinear systems. The approach involves the numerical solution, by Galerkin approximation, of the time-varying Hamilton-Jacobi-Bellman (HJB) equation and results in a nonlinear controller approximating the optimal tracking control law for a specified desired trajectory and cost function. Experimental results are presented for a nonlinear pendulum system.

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Model Predictive Satisficing Fuzzy Logic Control, Richard L. Frost, Michael A. Goodrich, Wynn C. Stirling Jun 1999

Model Predictive Satisficing Fuzzy Logic Control, Richard L. Frost, Michael A. Goodrich, Wynn C. Stirling

Faculty Publications

Model-predictive control, which is an alternative to conventional optimal control, provides controller solutions to many constrained and nonlinear control problems. However, even when a good model is available, it may be necessary for an expert to specify the relationship between local model predictions and global system performance. We present a satisficing fuzzy logic controller that is based on a receding control horizon, but which employs a fuzzy description of system consequences via model predictions. This controller considers the gains and losses associated with each control action, is compatible with robust design objectives, and permits flexible defuzzifier design. We demonstrate the …

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The Probability Density Of Spectral Estimates Based On Modified Periodogram Averages, David G. Long, Paul E. Johnson May 1999

The Probability Density Of Spectral Estimates Based On Modified Periodogram Averages, David G. Long, Paul E. Johnson

Faculty Publications

Welch's (1967) method for spectral estimation of averaging modified periodograms has been widely used for decades. Because such an estimate relies on random data, the estimate is also a random variable with some probability density function. Here, the PDF of a power estimate is derived for an estimate based on an arbitrary number of frequency bins, overlapping data segments, amount of overlap, and type of data window, given a correlated Gaussian input sequence. The PDFs of several cases are plotted and found to be distinctly non-Gaussian (the asymptotic result of averaging frequency bins and/or data segments), using the Kullback-Leibler distance …

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Ultrasonic Enhancement Of Antibiotic Action On Escherichia Coli Biofilms: An In Vivo Model, Andrea M. Rediske, Beverly L. Roeder, Maren K. Brown, Jared L. Nelson, Rachel L. Robison, David O. Draper, G. Bruce Schaalje, Richard A. Robison, William G. Pitt May 1999

Ultrasonic Enhancement Of Antibiotic Action On Escherichia Coli Biofilms: An In Vivo Model, Andrea M. Rediske, Beverly L. Roeder, Maren K. Brown, Jared L. Nelson, Rachel L. Robison, David O. Draper, G. Bruce Schaalje, Richard A. Robison, William G. Pitt

Faculty Publications

Biofilm infections are a common complication of prosthetic devices in humans. Previous in vitro research has determined that low-frequency ultrasound combined with aminoglycoside antibiotics is an effective method of killing biofilms. We report the development of an in vivo model to determine if ultrasound enhances antibiotic action. Two 24-h-old Escherichia coli (ATCC 10798) biofilms grown on polyethylene disks were implanted subcutaneously on the backs of New Zealand White female rabbits, one on each side of the spine. Low-frequency (28.48-kHz) and low-power-density (100- and 300-mW/cm2) continuous ultrasound treatment was applied for 24 h with and without systemic administration of gentamicin. The …

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Postlaunch Sensor Verification And Calibration Of The Nasa Scatterometer, David G. Long, Wu-Yang Tsai, James E. Graf, Carroll Winn, James N. Huddleston, R. Scott Dunbar, Michael H. Freilich, Frank J. Wentz, W. Linwood Jones May 1999

Postlaunch Sensor Verification And Calibration Of The Nasa Scatterometer, David G. Long, Wu-Yang Tsai, James E. Graf, Carroll Winn, James N. Huddleston, R. Scott Dunbar, Michael H. Freilich, Frank J. Wentz, W. Linwood Jones

Faculty Publications

Scatterometer instruments are active microwave sensors that transmit a series of microwave pulses and measure the returned echo power to determine the normalized radar backscattering cross section (sigma-0) of the ocean surface from which the speed and direction of near-surface ocean winds are derived. The NASA Scatterometer (NSCAT) was launched on board the ADEOS spacecraft in August 1996 and returned ten months of high-quality data before the failure of the ADEOS spacecraft terminated the data stream in June 1997. The purpose of this paper is to provide an overview of the NSCAT instrument and sigma-0 computation and to describe the …

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Cryosphere Applications Of Nscat Data, David G. Long, Mark R. Drinkwater May 1999

Cryosphere Applications Of Nscat Data, David G. Long, Mark R. Drinkwater

Faculty Publications

Though designed to measure vector winds over the ocean, new imaging techniques facilitate the use of NASA scatterometer data (NSCAT) in cryosphere studies. NSCAT provides data of unprecedented coverage, resolution, and quality which, when coupled with the scatterometer image reconstruction with filtering (SIRF) algorithm, enables images of O at resolutions approaching 8 km over stationary targets. Such images are useful in ice mapping and classification, and multidecadal studies are possible by comparison with Seasat Scatterometer (SASS) data. The utility of NSCAT data in polar ice studies is illustrated through a review of two cryosphere applications of NSCAT data: (1) sea-ice …

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Stratified Volume Diffractive Optical Elements As High Efficiency Gratings, Gregory P. Nordin, D. M. Chambers May 1999

Stratified Volume Diffractive Optical Elements As High Efficiency Gratings, Gregory P. Nordin, D. M. Chambers

Faculty Publications

We propose stratified volume diffractive optical elements as a new type of diffractive optical element that is capable of functioning as a high-efficiency grating in applications with requirements not suited to traditional holographic or diffractive optical techniques. In this approach, diffractive optical fabrication methods are used to construct an optical structure that emulates volume grating behavior. We discuss the diffraction properties of stratified volume diffractive optical elements and compare them with those used previously in both volume holographic optical elements and stratified volume holographic optical elements. A systematic design process is then presented for deriving structure parameters. We illustrate this …

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Full Issue Apr 1999

Full Issue

Inscape

No abstract provided.

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Editor's Note, Joseph Drew Apr 1999

Editor's Note, Joseph Drew

Comparative Civilizations Review

No abstract provided.

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En Route To Marquesado, Karl Chandler Apr 1999

En Route To Marquesado, Karl Chandler

Inscape

No abstract provided.

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Interval Matching And Control For Hexahedral Mesh Generation Of Swept Volumes, Jason F. Shepherd Apr 1999

Interval Matching And Control For Hexahedral Mesh Generation Of Swept Volumes, Jason F. Shepherd

Theses and Dissertations

Surface meshing algorithms require certain relationships among the number of intervals on the curves that bound the surface. Assigning the number of intervals to all of the curves in the model such that all relationships are satisfied is called interval assignment. Volume meshing algorithms also require certain relationships among the numbers of intervals on each of the curves on the volume. These relationships are not always captured by surface meshing requirements. This thesis presents a news technique for automatically identifying volume constraints. In this technique, volume constraints are grouped with surface constraints and are solved simultaneously. A sweepable volume has …

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The Probability Distribution Of Nscat Measurements, Paul E. Johnson, David G. Long Mar 1999

The Probability Distribution Of Nscat Measurements, Paul E. Johnson, David G. Long

Faculty Publications

NSCAT makes only indirect measurements of wind. The direct measurement is of the backscattered radar power. The signal power is contaminated by radiometric noise so a separate measurement of the noise power is subtracted from the signal-plus-noise measurement to estimate the backscattered power. Using the radar equation, sigma-0 is computed from the measured signal power. From multiple sigma-0 mesaurements made at different azimuth angles, the wind is estimated. In wind retrieval, the NSCAT sigma-0 measurements are assumed to have a Gaussian probability distribution with a variance which depends on the mean. Given this distribution model, the maximum-likelihood estimtor is formed …

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Observations Of Lattice Curvature Near The Interface Of A Deformed Aluminium Bicrystal, Brent L. Adams, W. E. King, S. Sun Mar 1999

Observations Of Lattice Curvature Near The Interface Of A Deformed Aluminium Bicrystal, Brent L. Adams, W. E. King, S. Sun

Faculty Publications

This work was partially supported by MRSEC Program of the National Science Foundation (DMR-9632556), and under the auspices of the US Department of Energy and Lawrence Livermore National Laboratory under contract W-7405- Eng-48. S. Sun gratefully acknowledges the comments of Professor E. T. Onat, Professor B. T. Chu and Professor W. Tong of the Mechanical Engineering Department at Yale University, and their valuable guidance in the process of completing this project as a doctoral dissertation. The assistance of B. El-Dasher of Carnegie-Mellon University is also gratefully acknowledged. Reported here is a study of the pattern of lattice curvature near the …

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Combustion Properties Of Biomass, B. M. Jenkins, Larry Lin Baxter 8507091, T. R. Miles Jr, T. R. Miles Mar 1999

Combustion Properties Of Biomass, B. M. Jenkins, Larry Lin Baxter 8507091, T. R. Miles Jr, T. R. Miles

Faculty Publications

Properties of biomass relevant to combustion are briefly reviewed. The compositions of biomass among fuel types are variable, especially with respect to inorganic constituents important to the critical problems of fouling and slagging. Alkali and alkaline earth metals, in combination with other fuel elements such as silica and sulfur, and facilitated by the presence of chlorine, are responsible for many undesirable reactions in combustion furnaces and power boilers. Reductions in the concentrations of alkali metals and chlorine, created by leaching the elements from the fuel with water, yield remarkable improvements in ash fusion temperatures and confirm much of what is …

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The Behavior Of Inorganic Material In Biomass-Fired Power Boilers: Field And Laboratory Experiences, Larry Lin Baxter 8507091, Thomas R. Miles, Thomas R. Miles Jr, Bryan M. Jenkins, Thomas Milne, David Dayton, Richard W. Bryers, Larry L. Oden Mar 1999

The Behavior Of Inorganic Material In Biomass-Fired Power Boilers: Field And Laboratory Experiences, Larry Lin Baxter 8507091, Thomas R. Miles, Thomas R. Miles Jr, Bryan M. Jenkins, Thomas Milne, David Dayton, Richard W. Bryers, Larry L. Oden

Faculty Publications

This paper highlights some of the major findings of the Alkali Deposits Investigation, a collaborative effort to understand the causes of unmanageable ash deposits in biomass-fired electric power boilers. A group of interested industrial institutions and the US DOE Energy Efficiency and Renewable Energy Office's Biomass Power Program through the National Renewable Energy Laboratory jointly sponsored the project. The industries contributed both funding and, in most cases, use of facilities to the project and included Mendota Biomass Power and Woodland Biomass Power (both associated with Thermo Electron Energy Systems), CMS Generation Operating (formerly Hydra-Co Operations), Wheelabrator, Shasta and Hudson Energy, …

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Resolving Problems In Engineering Ethics: Precept And Example, Joel C. Adair Mar 1999

Resolving Problems In Engineering Ethics: Precept And Example, Joel C. Adair

Theses and Dissertations

This thesis has served to accomplish several objectives. First, a foundation was laid for the consideration of ethical factors in an engineering context. This was done by first establishing the need for ethical judgement in the engineering disciplines. A summary of several significant classical ethical theories followed, providing several tools with which to evaluate decisions that have ethical implications. Finally, the conclusion was made that the best framework for making ethical decisions is found in the application of the virtues espoused by the gospel of Jesus Christ.

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An Empirical Test Of Analogical Modeling: The K/Ø Alternation, Anton Rytting Feb 1999

An Empirical Test Of Analogical Modeling: The K/Ø Alternation, Anton Rytting

Deseret Language and Linguistic Society Symposium

No abstract provided.

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Full Issue, Deseret Language And Linguistics Society Feb 1999

Full Issue, Deseret Language And Linguistics Society

Deseret Language and Linguistic Society Symposium

No abstract provided.

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Who Is "Him"? Determining Pronominal Reference, Deryle Lonsdale Feb 1999

Who Is "Him"? Determining Pronominal Reference, Deryle Lonsdale

Deseret Language and Linguistic Society Symposium

No abstract provided.

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Determination Of A Methane Intermolecular Potential Model For Use In Molecular Simulations From Ab Initio Calculations, Richard L. Rowley, Tapani A. Pakkanen Feb 1999

Determination Of A Methane Intermolecular Potential Model For Use In Molecular Simulations From Ab Initio Calculations, Richard L. Rowley, Tapani A. Pakkanen

Faculty Publications

The possibility of obtaining an accurate site-site potential model suitable for use in molecular dynamics (MD) simulations of methane from ab initio calculations has been explored. Counterpoise-corrected (CPC), supermolecule, ab initio energies at the MP2/6-311 + G(2df,2pd) level were computed for eleven relative orientations of two methane molecules as a function of C-C separation distance. C-C, C-H, and H-H interaction parameters in a pairwise-additive, site-site potential model for rigid methane molecules were regressed from the ab initio energies, and the resultant model accurately reproduced the ab initio energies. The model suggests that C-H attractions are dominant in weakly binding the …

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