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A Theory Of Satisficing Decisions And Control, Richard L. Frost, Michael A. Goodrich, Wynn C. Stirling Nov 1998

A Theory Of Satisficing Decisions And Control, Richard L. Frost, Michael A. Goodrich, Wynn C. Stirling

Faculty Publications

The existence of an optimal control policy and the techniques for finding it are grounded fundamentally in a global perspective. These techniques can be of limited value when the global behavior of the system is difficult to characterize, as it may be when the system is nonlinear, when the input is constrained, or when only partial information is available regarding system dynamics or the environment. Satisficing control theory is an alternative approach that is compatible with the limited rationality associated with such systems. This theory is extended by the introduction of the notion of strong satisficing to provide a systematic …

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Full Issue, Vol. 58 No. 4 Oct 1998

Full Issue, Vol. 58 No. 4

Great Basin Naturalist

No abstract provided.

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Algal Composition Of Microbiotic Crusts From The Central Desert Of Baja California, Mexico, Valerie R. Flechtner, Jeffrey R. Johansen, William H. Clark Oct 1998

Algal Composition Of Microbiotic Crusts From The Central Desert Of Baja California, Mexico, Valerie R. Flechtner, Jeffrey R. Johansen, William H. Clark

Great Basin Naturalist

A total of 66 algal species representing 32 genera were recovered from soils of 10 sites in the Cataviña region of the Central Desert of Baja California, Mexico. The most common species encountered were the cyanophytes Nostoc commune and Schizothrix calcicola, the chlorophyte Myrmecia astigmatica, and the diatoms Hantzschia amphioxys, Hantzschia amphyoxys f. capitata, Luticola cohnii, Luticola mutica, and Pinnularia borealis var. scalaris. Nine species not found in any previous studies of North American desert soils were present in our study sites, including 3 taxa new to science: Cylindrocystis brebissonii var. deserti, var. nov.; Elakatothrix …

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Committee Activities, Jean Han, Hyokyoung Lee, Philip Melzer Oct 1998

Committee Activities, Jean Han, Hyokyoung Lee, Philip Melzer

Journal of East Asian Libraries

No abstract provided.

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Robert M. Kingdon, Adultery And Divorce In Calvin's Geneva., Raymond J. Lewis Oct 1998

Robert M. Kingdon, Adultery And Divorce In Calvin's Geneva., Raymond J. Lewis

Comparative Civilizations Review

No abstract provided.

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Carroll Quigley On The Matrix Of Civilizations: A Dialectic, Arthur S. Iberall Oct 1998

Carroll Quigley On The Matrix Of Civilizations: A Dialectic, Arthur S. Iberall

Comparative Civilizations Review

No abstract provided.

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Ssu K'U Ch'Üan Shu, Its Continuing Series And Selections, And Their Acquisitions In North America, Guoqing Li Oct 1998

Ssu K'U Ch'Üan Shu, Its Continuing Series And Selections, And Their Acquisitions In North America, Guoqing Li

Journal of East Asian Libraries

No abstract provided.

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Pinyin Conversion Reports, Robert Hiatt, Philip Melzer Oct 1998

Pinyin Conversion Reports, Robert Hiatt, Philip Melzer

Journal of East Asian Libraries

No abstract provided.

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Java Applets Enhance Learning In A Freshman Ece Course, Charles R. Graham, Timothy N. Trick Oct 1998

Java Applets Enhance Learning In A Freshman Ece Course, Charles R. Graham, Timothy N. Trick

Faculty Publications

The goals of our work have been to enhance the learning environment of our students and to increase the productivity of faculty by freeing them from the drudgery of grading homework and quizzes, as well as the time required to record and compute grades. We have achieved these goals by means of the highly interactive World Wide Web (WWW)-based learning environment provided by MallardTM, 1,2 and by the development of several java applets within the Mallard environment to enhance the learning process. These Java applets are the subject of this paper. They include the ability to draw timing diagrams and …

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An Analysis Of Temperature Dependent Photoluminescence Line Shapes In Ingan, John S. Colton, K. L. Teo, P. Y. Yu, E. R. Weber, M. F. Li, W. Lui, K. Uchida, H. Tokunaga, N. Akutsu, K. Matsumoto Sep 1998

An Analysis Of Temperature Dependent Photoluminescence Line Shapes In Ingan, John S. Colton, K. L. Teo, P. Y. Yu, E. R. Weber, M. F. Li, W. Lui, K. Uchida, H. Tokunaga, N. Akutsu, K. Matsumoto

Faculty Publications

Photoluminescence (PL) line shapes in InGaN multiple quantum well structures have been studied experimentally and theoretically between 10 and 300 K. The higher temperature PL spectra can be fitted qualitatively with a thermalized carrier distribution and a broadened joint-density-of-states. The low temperature PL line shapes suggest that carriers are not thermalized, as a result of localization by band-gap fluctuations. We deduce a localization energy of ~7 meV as compared with an activation energy of ~63 meV from thermal quenching of the PL intensity. We thus conclude that this activation energy and the band-gap fluctuation most likely have different origins.

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Catalogs Of Temperatures And [Fe/H] Averages For Evolved G And K Stars, B. J. Taylor Sep 1998

Catalogs Of Temperatures And [Fe/H] Averages For Evolved G And K Stars, B. J. Taylor

Faculty Publications

A catalog of mean values of [Fe/H] for evolved G and K stars is described. The zero point for the catalog entries has been established by using differential analyses. Literature sources for those entries are included in the catalog. The mean values are given with rms errors and numbers of degrees of freedom, and a simple example of the use of these statistical data is given. For a number of the stars with entries in the catalog, temperatures have been determined. A separate catalog containing those data is briefly described.

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Since Joseph Smith's Time: Lexical Semantic Shifts In The Book Of Mormon, Renee Bangerter Aug 1998

Since Joseph Smith's Time: Lexical Semantic Shifts In The Book Of Mormon, Renee Bangerter

Theses and Dissertations

In the years since Joseph Smith completed the translation of the Book of Mormon, the English language has changed; some common phraseologies and word meanings are dissimilar to today's. Often, in reading the Book of Mormon, we impose our current definitions onto terms that in 1830 had a different meaning. Our interpretation of these words, as well as the passages in which they are found, is skewed by our modern definitions. These words, when they occur in the Book of Mormon, demonstrate dialectal and obsolete senses. In the case of some words, the dialectal or obsolete sense is so far …

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Evaluation Of Personal Communications Dual-Antenna Handset Diversity Performance, Michael A. Jensen, Joseph S. Colburn, Yahya Rahmat-Samii, Gregory J. Pottie Aug 1998

Evaluation Of Personal Communications Dual-Antenna Handset Diversity Performance, Michael A. Jensen, Joseph S. Colburn, Yahya Rahmat-Samii, Gregory J. Pottie

Faculty Publications

In personal wireless communications systems, multipath propagation has a significant effect on system design and performance. Signal strength fading caused by destructive interference between multiple replicas of the signal of interest arriving at the receiver over different paths often is the limiting factor in system range/fidelity. Antenna diversity is one technique that can be used to help overcome multipath fading. This paper presents a description of experiments, data processing, and results used to evaluate the diversity performance of three candidate dual-antenna handset configurations: two side-mounted planar-inverted F antennas (PIFAs), a back-mounted PIFA with a top-mounted helix, a top-mounted PIFA, and …

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Nonlinear Optimal Control Design Of A Missile Autopilot, Tim Mclain, Randal W. Beard Aug 1998

Nonlinear Optimal Control Design Of A Missile Autopilot, Tim Mclain, Randal W. Beard

Faculty Publications

The application of a new nonlinear optimal 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-Bellman equation by Successive Galerkin Approximation. Using this approach, feedback controllers are computed by an iterative application of a numerical Galerkin-type PDE solver. Simulation results demonstrating the application of this approach to the design of a missile autopilot are presented.

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Influence Of Ash Deposit Chemistry And Structure On Physical And Transport Properties, Larry Lin Baxter 8507091 Jul 1998

Influence Of Ash Deposit Chemistry And Structure On Physical And Transport Properties, Larry Lin Baxter 8507091

Faculty Publications

Boiler ash deposits generated during combustion of coal, biomass, black liquor, and energetic materials affect both the net plant efficiency and operating strategy of essentially all boilers. Such deposits decrease convective and radiative heat exchange with boiler heat transfer surfaces. In many cases, even a small amount of ash on a surface decreases local heat transfer rates by factors of three or more. Apart from their impact on heat transfer, ash deposits in boilers represent potential operational problems and boiler maintenance issues, including plugging, tube wastage (erosion and corrosion), and structural damage. This report relates the chemistry and microstructural properties …

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Natural History Of A Saline Mound Ecosystem, Robert R. Blank, James A. Young, James D. Trent, Debra E. Palmquist Jul 1998

Natural History Of A Saline Mound Ecosystem, Robert R. Blank, James A. Young, James D. Trent, Debra E. Palmquist

Great Basin Naturalist

Along the margins of playas in northwestern Nevada, a salt-tolerant plant community occupies mounds that dot a largely unvegetated landscape. In this environment we studied soil development and plant-soil relationships. The mounds, averaging 0.3 m in height, are occupied by the shrubs Allenrolfea occidentalis (iodine bush), Sacrobatus vermiculatus (black greasewood), and Atriplex lentiformis spp. torreyi (Torrey saltbush). Distichlis spicata (desert saltgrass) is the only herbaceous plant occupying this community. Soil salinity decreases with depth in this environment, and content of aqueous-extractable solutes is significantly influenced by site-specific vegetation. Content of silt, clay, and salt in mound surface horizons suggests a …

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Gap Analysis Of The Vegetation Of The Intermountain Semi-Desert Ecoregion, David M. Stoms, Frank W. Davis, Kenneth L. Driese, Kelly M. Cassidy, Michael P. Murray Jul 1998

Gap Analysis Of The Vegetation Of The Intermountain Semi-Desert Ecoregion, David M. Stoms, Frank W. Davis, Kenneth L. Driese, Kelly M. Cassidy, Michael P. Murray

Great Basin Naturalist

A conservation gap analysis was conducted for the Intermountain Semi-Desert ecoregion to assess the representation of land-cover types within areas managed primarily for biodiversity objectives. Mapped distributions of plant communities were summarized by land-management status categories. The total amount of land permanently protected in the ecoregion is

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Winter Macroinvertebrate Communities In Two Montane Wyoming Streams, Christopher M. Pennuto, Frank Denoyelles Jr., Mark A. Conrad, Frank A. Vertucci, Sharon L. Dewey Jul 1998

Winter Macroinvertebrate Communities In Two Montane Wyoming Streams, Christopher M. Pennuto, Frank Denoyelles Jr., Mark A. Conrad, Frank A. Vertucci, Sharon L. Dewey

Great Basin Naturalist

Macroinvertebrate communities were examined on 4 winter dates over a 4-yr period in 2 high-altitude Rocky Mountain streams to document overwintering assemblages potentially experiencing spring acid pulses. Taxa richness values were comparable to other published lists for alpine and montane stream systems despite the fact that most literature reflected summer collections. Mean benthic density ranged from 1406 to 19,734 organisms/m2, and drift rates ranged from 0 to 1740 organisms/100 m3. Benthic collections showed higher taxa richness than drift collections while the Ephemeroptera and Plecoptera occurred in greater proportions in drift than in benthos. The Nemouridae (Plecoptera), …

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Full Issue, Vol. 58 No. 3 Jul 1998

Full Issue, Vol. 58 No. 3

Great Basin Naturalist

No abstract provided.

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Development And Experimental Validation Of An Underwater Manipulator Hydrodynamic Model, Timothy W. Mclain, Stephen M. Rock Jul 1998

Development And Experimental Validation Of An Underwater Manipulator Hydrodynamic Model, Timothy W. Mclain, Stephen M. Rock

Faculty Publications

Hydrodynamic forces can be large and hence have a significant effect on the dynamic performance of underwater manipulation systems. this paper investigates these forces for a cylindrical single-link arm undergoing motions that are characteristics of a robotic manipulator. Based on flow visualization, theoretical analysis, and experimental measurements, a new model is developed that describes these forces. This model differs from previous models in that the drag and added-mass coefficients are state-dependent functions that depend on the distance traveled by the arm. A factor of four improvement in accuracy is demonstrated over standard constant-coefficient models.

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Successive Galerkin Approximations To The Nonlinear Optimal Control Of An Underwater Robotic Vehicle, Timothy Mclain, Randal W. Beard Jul 1998

Successive Galerkin Approximations To The Nonlinear Optimal Control Of An Underwater Robotic Vehicle, Timothy Mclain, Randal W. Beard

Faculty Publications

The application of a new nonlinear optimal control strategy to the station-keeping control of an underwater robotic vehicle is considered. The control approach described and demonstrated here is based upon the numerical approximation of solutions to the Hamilton-Jacobi-Bellman equation. These solutions are computed by an iterative application of Galerkin's method. Preliminary simulation results demonstrating the application of this approach to the control of an underwater vehicle in the horizontal plane are presented.

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Committee Activities, Lynne Kutsukake, Sachie Noguchi Jun 1998

Committee Activities, Lynne Kutsukake, Sachie Noguchi

Journal of East Asian Libraries

No abstract provided.

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Full Issue Jun 1998

Full Issue

Swiss American Historical Society Review

No abstract provided.

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Off To Dallas, Felix P. Bentz Jun 1998

Off To Dallas, Felix P. Bentz

Swiss American Historical Society Review

The nine short stories which you will read below represent "Chapter V" of my Memoirs. I began to write down the story of my life in 1991 after finishing my last project as a consultant. The initial reason for this was to tell my children and grandchildren about their ancestors and what it was like to be growing up in Switzerland.

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Gemeindegeschichte Als Vergleichende Geschichte: The Church Of Jesus Christ Of Latter-Day Saints In East Germany, Bruce W. Hall Jun 1998

Gemeindegeschichte Als Vergleichende Geschichte: The Church Of Jesus Christ Of Latter-Day Saints In East Germany, Bruce W. Hall

Theses and Dissertations

From 1945 until the fall of the Berlin Wall in 1989, the Church of Jesus Christ of Latter-day Saints (LDS) in the former German Democratic Republic (GDR) endured the hardships of existing as a religious organization under a Communist regime. An evaluation of the LDS Church within the category of general and minority religions, which serves as a microcosmic evaluation of religion in the GDR, constitutes one part of this study. The uniqueness of the LDS Church and its experience - especially its American ties, ironically earlier a liability and later an asset - make it a candidate for a …

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Internship At Otani University Library And Conferences/Meetings Related To Libraries In Japan, Toshie Marra Jun 1998

Internship At Otani University Library And Conferences/Meetings Related To Libraries In Japan, Toshie Marra

Journal of East Asian Libraries

No abstract provided.

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Digital Library For The 21-St Century: Tsukuba University Library Digitized Information Public Services (Tulips), Hisami Konishi Springer Jun 1998

Digital Library For The 21-St Century: Tsukuba University Library Digitized Information Public Services (Tulips), Hisami Konishi Springer

Journal of East Asian Libraries

No abstract provided.

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A Practical Algorithm For Designing H∞ Control Laws, Timothy Mclain, Randal W. Beard Jun 1998

A Practical Algorithm For Designing H∞ Control Laws, Timothy Mclain, Randal W. Beard

Faculty Publications

We describe an approximation method for the Hamilton-Jacobi-Isaacs (HJI) equation that results in feedback control. The approximation is accomplished via a two-step successive Galerkin approximation scheme. An application of the technique to the control of the forward motion of an underwater vehicle is described.

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Fuel Equalized Retargeting For Separated Spacecraft Interferometry, Timothy Mclain, Randal W. Beard, Fred Y. Hadaegh Jun 1998

Fuel Equalized Retargeting For Separated Spacecraft Interferometry, Timothy Mclain, Randal W. Beard, Fred Y. Hadaegh

Faculty Publications

Motivated by NASA's proposed Deep Space 3 interferometer mission, the paper considers the problem of reorienting a constellation of spacecraft such that the total fuel distributed across the constellation is both conserved and expended uniformly. The spacecraft constellation is controlled to reorient as if it were a rigid body. Two approaches to fuel equalization are investigated. The first approach picks a point of rotation a priori that optimizes an objective function that trades off minimum-fuel maneuvers and maneuvers that equalize the fuel. Since the point of rotation is selected a priori and is fixed during the rotation, this approach is …

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Constructing High Order Perceptrons With Genetic Algorithms, Timothy L. Andersen, Tony R. Martinez May 1998

Constructing High Order Perceptrons With Genetic Algorithms, Timothy L. Andersen, Tony R. Martinez

Faculty Publications

Constructive induction, which is defined to be the process of constructing new and useful features from existing ones, has been extensively studied in the literature. Since the number of possible high order features for any given learning problem is exponential in the number of input attributes (where the order of a feature is defined to be the number of attributes of which it is composed), the main problem faced by constructive induction is in selecting which features to use out of this exponentially large set of potential features. For any feature set chosen the desirable characteristics are minimality and generalization …

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