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1999

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Modeling Habitat Attributes Of Cavity-Nesting Birds In The Uinta Mountains, Utah: A Hierarchical Approach, Joshua J. Lawler May 1999

Modeling Habitat Attributes Of Cavity-Nesting Birds In The Uinta Mountains, Utah: A Hierarchical Approach, Joshua J. Lawler

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Birds may have the ability to view their environments at a wide range of spatial scales; accordingly, they may make habitat-selection decisions at multiple spatial scales. I investigated the implications of hierarchy theory and a landscape perspective on nest-site selection in cavity-nesting birds in the Uinta Mountains in northeastern Utah. I used three different approaches to address the concept of a multi-scaled nest-site selection process. First, I conducted an exploratory study in which I investigated nest-site selection at three spatial scales for Red-naped Sapsucker (Sphyrapicus nuchalis), Northern Flicker (Colaptes auratus), Tree Swallow (Tachycineta bicolor), and …


Investigation Of The Determinants Of African Savanna Vegetation Distribution: A Case Study From The Lower Omo Basin, Ethiopia, Catherine A. Schloeder May 1999

Investigation Of The Determinants Of African Savanna Vegetation Distribution: A Case Study From The Lower Omo Basin, Ethiopia, Catherine A. Schloeder

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The Ethiopian Wildlife Conservation Organization has little information on the extent and ecological determinants of plant species composition and distribution in Omo National Park. Elsewhere, the determinants of African savanna vegetation dynamics have been the focus of numerous investigations, yet our understanding of the hierarchical nature and relative importance of any relationships remains very general. As well, our ability to derive predictions about vegetation responses is limited to extreme generalizations. African savanna landscape ecotones have received even less attention than most landscapes. In this dissertation, I test hypotheses about plant species distribution-determinant relationships in Omo National Park, a park that …


Molecular Characterization Of Soil Ammonia-Oxidizing Bacteria Based On The Genes Encoding Ammonia Monooxygenase, Jose Javier Alzerreca May 1999

Molecular Characterization Of Soil Ammonia-Oxidizing Bacteria Based On The Genes Encoding Ammonia Monooxygenase, Jose Javier Alzerreca

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Ammonia-oxidizing bacteria (AOB) are chemolithotrophs that oxidize ammonia/ammonium to nitrite in a two-step process to obtain energy for survival. AOB are difficult to isolate from the environment and iso lated strains may not represent the diversity in soil. A genetic database and molecular tools were developed based on the ammonia monooxygenase (AMO) encoding genes that can be used to assess the diversity of AOB that exist in soil and aquatic environments without the isolation of pure cultures. The amo genes have excellent potential as molecular markers; since AMO is only found in the AOB and is essential for their metabolism, …


Sequence Stratigraphy And Paleoecology Of The Middle Cambrian Spence Shale Member Of The Langston Formation Of Northeastern Utah And Southeastern Idaho, Scott H. Wright May 1999

Sequence Stratigraphy And Paleoecology Of The Middle Cambrian Spence Shale Member Of The Langston Formation Of Northeastern Utah And Southeastern Idaho, Scott H. Wright

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The Middle Cambrian Spence Shale Member contains meter-scale, shallowing-up cycles (parasequences) and record approximately 360 ky of deposition. These meter-scale cycles are nested within transgressive systems tracts (TST) and highstand systems tracts (HST) which reflect different stages of a lower-order, higher-magnitude sea-level excursion.

Fossil assemblages are located in stratigraphic positions within the Spence Shale Member that can be predicted on the basis of sequence architecture. The cycle architecture, taphonomy, and geochemistry of the Spence parasequences confirm synthetic sections and theoretical models of meter-scale cycles developed in other studies. Delineation of meter-scale cycles, based on taphonomic and sedimentologic criteria, allows high-resolution …


Vessiot: A Maple Package For Varational And Tensor Calculus In Multiple Coordinate Frames, Charles E. Miller May 1999

Vessiot: A Maple Package For Varational And Tensor Calculus In Multiple Coordinate Frames, Charles E. Miller

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The Maple V package Vessiot is an extensive set of procedures for performing computations in variational and tensor calculus. Vessiot is an extension of a previous package, Helmholtz, which was written by Cinnamon Hillyard for performing operations in the calculus of variations. The original set of commands included standard operators on differential forms, Euler-Lagrange operators, the Lie bracket operator, Lie derivatives, and homotopy operators. These capabilities are preserved in Vessiot, and enhanced so as to function in a multiple coordinate frame context. In addition, a substantial number of general tensor operations have been added to the package. These include standard …


Estimating R2 Shrinkage In Multiple Regression: A Comparison Of Different Analytical Methods, Ping Yin May 1999

Estimating R2 Shrinkage In Multiple Regression: A Comparison Of Different Analytical Methods, Ping Yin

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

This study investigated the effectiveness of various analytical methods used for estimating R2 shrinkage in multiple regression analysis. Two categories of analytical formulae were identified: estimators of the population squared multiple correlation coefficient (ρ2), and estimators of the population cross-validity coefficient (ρc2). To avoid possible confounding factors that might be associated with a real data set such as data nonnormality, lack of precise population parameters, different degrees of multicollinearity among the predictor variables, and so forth, the Monte Carlo method was used to simulate multivariate normal sample data, with prespecified population parameters such as …


Chemical And Hydrostratigraphic Characterization Of Ground Water And Surface Water Interactions In Cache Valley, Utah, J. Mike Robinson May 1999

Chemical And Hydrostratigraphic Characterization Of Ground Water And Surface Water Interactions In Cache Valley, Utah, J. Mike Robinson

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

A series of five east-west and two north-south hydrostratigraphic cross sections were drawn from drillers' logs of water wells within the southern half of Cache Valley, Utah. These cross-sections demonstrate that ground water flow to streams is restricted by a continuous low- II permeability layer, nearly 100-feet thick. This layer was correlated to the lake-bottom deposits of the Bonneville (30,000 -13,000 years ago) and Little Valley (140,000 - 90,000 years ago) cycles of the ancient Lake Bonneville.

The most productive aquifers in the valley, collectively termed the principal aquifer , are in the southeast corner , approximately between Smithfield and …


The Arccos And Lommel Formulations—Approximate Closed-Form Diffraction Corrections, Charles J. Daly, Navalgund A. H. Rao May 1999

The Arccos And Lommel Formulations—Approximate Closed-Form Diffraction Corrections, Charles J. Daly, Navalgund A. H. Rao

Articles

A closed-form frequency-domain formalism for spatially integrated diffraction corrections is proposed. Spatially integrated diffraction corrections are necessary when trying to characterize material with ultrasonic probing. In the case of piston transducers and point receivers, the Lommel diffraction formulation is used when the excitation is monochromatic, and the arccos diffraction formulation is used when the excitation is impulsive. The Lommel and arccos formulations are usually treated separately; here, they are connected. Specifically, the arccos diffraction formulation and Lommel diffraction formulation are shown to form an approximate Fourier transform pair. Since the Lommel formulation is amenable to closed-form spatial integration, Lommel functions …


Commencement Program Features U.S. Sen. Thad Cochran In Keynote, Tina Hahn May 1999

Commencement Program Features U.S. Sen. Thad Cochran In Keynote, Tina Hahn

University of Mississippi News

... Alumnus Cochran Tells Graduates to Never Give Up' in Pursuit of Fulfillment


Changing The Image Of Vocational Education, Laura Timberman May 1999

Changing The Image Of Vocational Education, Laura Timberman

Theses and Dissertations

The purpose of this study was to (1) determine existing opinions of vocational education and (2) identify steps to be taken by vocational schools to improve image problems and to attract students.

A written survey was sent to the 21 New Jersey public vocational school superintendents. Twenty responses were received.

The results of the study indicate that the term "vocational" indeed carries a stigma. The leading association for vocational education recently underwent a name change. Many vocational schools are following suit, changing their names to eliminate the word "vocational."

The study also addressed the new courses being taught at vocational …


Black Holes And The Sym Diagram. Ii, Emil Martinec, Vatche Sahakian May 1999

Black Holes And The Sym Diagram. Ii, Emil Martinec, Vatche Sahakian

All HMC Faculty Publications and Research

The complete phase diagram of objects in M theory compactified on tori Tp,p=1,2,3, is elaborated. Phase transitions occur when the object localizes on cycle(s) (the Gregory-Laflamme transition), or when the area of the localized part of the horizon becomes one in string units (the Horowitz-Polchinski correspondence point). The low-energy, near-horizon geometry that governs a given phase can match onto a variety of asymptotic regimes. The analysis makes it clear that the matrix conjecture is a special case of the Maldacena conjecture.


An On-Line Test For Polycyclic Aromatic Hydrocarbons In The Flue Gas From Coal Combustion In An Fbc System, Wenjun Han May 1999

An On-Line Test For Polycyclic Aromatic Hydrocarbons In The Flue Gas From Coal Combustion In An Fbc System, Wenjun Han

Masters Theses & Specialist Projects

Polycyclic Aromatic Hydrocarbons (PAHs) are environmental pollutants that have received considerable attention because of their carcinogenic and mutagenic effects. Due to the extensive amount of data suggesting the hazards of these compounds, 16 PAHs are on the Environmental Protection Agency (EPA) Priority Pollutant List. These compounds are often emitted into the atmosphere by way of combustion processes. Thus, analysis of these compounds during coal combustion is an important task. Three 1000-hour coal combustion burns were performed using the 0.1 MW (0.3 m) bench-scale Fluidized Bed Combustor (FBC) in the Combustion Laboratory at Western Kentucky University. The data for this thesis …


Does Tall Grass Reduce Bird Numbers On Airports?: Results Of Pen Test With Canada Geese And Field Trials At Two Airports, 1998, Thomas W. Seamans, Richard A. Dolbeer, Mark S. Carrara, Richard B. Chipman May 1999

Does Tall Grass Reduce Bird Numbers On Airports?: Results Of Pen Test With Canada Geese And Field Trials At Two Airports, 1998, Thomas W. Seamans, Richard A. Dolbeer, Mark S. Carrara, Richard B. Chipman

Bird Strike Committee-USA/Canada Joint Annual Meeting: 1st (1999)

A suggested management plan to reduce bird numbers and bird-aircraft collisions at airports is to maintain grass 15-25 cm high. However, 3 studies conducted in the United States in 1998 indicated tall-grass management may not result in fewer birds. First, Canada geese (Branta canadensis), in a replicated experiment lasting 9 days in 6 pens in Ohio, showed no preference (P = 0.53) for short-grass (4-11 cm) over tall-grass (16-21 cm) plots. Second, we compared bird use of 8 tall- (23.3 ± 0.5 cm high, x ± SE) and 8 short- (14.3 ± 0.2) grass plots totaling 46 ha at Burke …


Center For Sustainable Agricultural Systems Newsletter, May/June 1999 May 1999

Center For Sustainable Agricultural Systems Newsletter, May/June 1999

Center for Sustainable Agricultural Systems: Newsletter (1993–2000)

Contents:

The Farmer and the Dean

University Role in Biotechnology: Who Owns Genes and Diversity?

CSAS Volume 9 Discusses Watersheds

SARE Appoints Paula Ford North Central PDP

Coordinator Policy Project Identifies Retention of Farms and Farmland as Top Priorities

Olson Heads to Kentucky

Organic Grain Farming Workshops

Two Alternative Agriculture Conferences in Midwest


Clemson Commencement Program, May 1999, Clemson University May 1999

Clemson Commencement Program, May 1999, Clemson University

Clemson Commencement Programs

No abstract provided.


Commencement 1999, Sacred Heart University May 1999

Commencement 1999, Sacred Heart University

Commencement Programs

Program for the Graduate and Undergraduate ceremonies held May 23 1999.


Modes And Quasi-Modes For M = 1,2 In A Gyrokinetic Model For A Non-Neutral Plasma, S. Neil Rasband, Ross L. Spencer May 1999

Modes And Quasi-Modes For M = 1,2 In A Gyrokinetic Model For A Non-Neutral Plasma, S. Neil Rasband, Ross L. Spencer

Faculty Publications

Modes and quasi-modes for m = 1,2 are studied in a gyro-kinetic model for a pure-electron plasma. Only z-independent perturbations are considered. Numerical methods are used to solve the relevant differential equations for smooth, analytic density profiles. Different temperatures and representative profiles are considered and comparison is made with the familiar cold fluid model from which the results depart but little, except at higher temperatures. A continuum component to the spectrum, present in the cold-fluid model, remains in the gyro-kinetic model to the order considered.


Use Of Evolutionary Factor Analysis In The Spectroelectrochemistry Of Escherichia Coli Sulfite Reductase Hemoprotein And A Mo/Fe/S Cluster, Robert L. Keesey, Michael D. Ryan May 1999

Use Of Evolutionary Factor Analysis In The Spectroelectrochemistry Of Escherichia Coli Sulfite Reductase Hemoprotein And A Mo/Fe/S Cluster, Robert L. Keesey, Michael D. Ryan

Chemistry Faculty Research and Publications

The deconvolution of spectroelectrochemical data is often quite difficult if the spectra of intermediates are not known. Factor analysis, however, has been shown to be a powerful technique which can make it possible to deconvolute overlapping spectra. In this work, evolving factor analysis will be used to determine the number of intermediates and the spectra of those species for two typical spectroelectrochemical experiments:  linear scan voltammetry and chronoabsorptometry in a thin-layer cell. The first system was the reduction of E. coli sulfite reductase hemoprotein (SiR-HP). Principal factor analysis indicated that three species were present. By using evolving factor analysis, …


Particle Simulation In Contact Mechanics Of A Bouncing Elastic Ball, Donald Greenspan May 1999

Particle Simulation In Contact Mechanics Of A Bouncing Elastic Ball, Donald Greenspan

Mathematics Technical Papers - Archive

An elastic ball is simulated by considering lumped mass molecular sets called particles. Particles are allowed to interact only locally in a fashion similar to that employed in molecular mechanics. Under local and gravity forces an n-body problem results when initial data are prescribed. By scaling the forces, the resulting n-body problem is solved numerically using only a scientific personal computer. A variety of examples of bouncing balls are described and discussed.


Wing And Primary Growth Of The Wandering Albatross, S. D. Berrow, N. Huin, R. Humpidge, A. W. Murray, P. A. Prince May 1999

Wing And Primary Growth Of The Wandering Albatross, S. D. Berrow, N. Huin, R. Humpidge, A. W. Murray, P. A. Prince

Condor

No abstract provided.


Wright State University College Of Engineering And Computer Science Bits And Pcs Newsletter, Volume 15, Number 5, May 1999, College Of Engineering And Computer Science, Wright State University May 1999

Wright State University College Of Engineering And Computer Science Bits And Pcs Newsletter, Volume 15, Number 5, May 1999, College Of Engineering And Computer Science, Wright State University

BITs and PCs Newsletter

An eight page newsletter created by the Wright State University College of Engineering and Computer Science that addresses the current affairs of the college.


Alumnews, May 1999, Alumni Association, Wright State University May 1999

Alumnews, May 1999, Alumni Association, Wright State University

AlumNews

Six page issue of the AlumNews newsletter. This newsletter focuses on news about programs, events, and activities for alumni from Wright State University.


University Of Central Florida Undergraduate Catalog, 1999 - 2000, University Of Central Florida May 1999

University Of Central Florida Undergraduate Catalog, 1999 - 2000, University Of Central Florida

UCF Catalogs

No abstract provided.


Reversal Flow In Fixed-Bed Reactors Operating Under Reaction-Regeneration Cycles, Daniel O. Borio, Noemi S. Schbib, Jorge E. Gatica May 1999

Reversal Flow In Fixed-Bed Reactors Operating Under Reaction-Regeneration Cycles, Daniel O. Borio, Noemi S. Schbib, Jorge E. Gatica

Chemical & Biomedical Engineering Faculty Publications

The unsteady state simulation of a set of industrial fixed-bed reactors is presented. The catalytic dehydrogenation of 1-butene into 1-3-butadiene is selected as case study. These reactors operate under reaction-regeneration cycles. Each stage of the process, i.e., dehydrogenation (deactivation by coking), steam purge, oxidative regeneration and evacuation, is simulated by means of the corresponding dynamic model. The kinetic parameters used in the dehydrogenation and regeneration stages for a Cr2O3/Al2O3 catalyst are taken from the literature. The performance of the reactors is investigated for two different operation modes: conventional …


The Effect Of Laser Bandwidth On The Signal Detected In Two-Color, Resonant Four-Wave Mixing Spectroscopy, F. Di Teodoro, Elizabeth Mccormack May 1999

The Effect Of Laser Bandwidth On The Signal Detected In Two-Color, Resonant Four-Wave Mixing Spectroscopy, F. Di Teodoro, Elizabeth Mccormack

Physics Faculty Research and Scholarship

The effect of laser line shape and bandwidth on the signal detected in two-color, resonant four-wave mixing (TC-RFWM) spectroscopy is determined by means of an ab initio calculation of the third-order polarization based on diagrammatic perturbation theory. Modifications to the approach previously used for the case of delta-function laser line shapes are made by introducing a different treatment of the rotating wave approximation and phase-matching conditions. A three-level excitation scheme for double-resonance spectroscopy of bound and quasibound states is analyzed. In the case of Lorentzian laser line shapes, analytic expressions for the signal line profile are obtained for each excitation …


Social Work Assessment: Case Theory Construction, Cynthia D. Bisman May 1999

Social Work Assessment: Case Theory Construction, Cynthia D. Bisman

Graduate School of Social Work and Social Research Faculty Research and Scholarship

To intervene effectively, social workers need to make sense of clients and their situations. A case theory approach to assessment provides a framework to formulate assessments that are clear and directly related to the real-world problems clients present. Explaining the problem situation, case theory forms the foundation for selection of intervention strategies and methods to achieve change. Building case theory requires practitioner abilities to form concepts, relate concepts into propositions, develop hypotheses, and organize these into a coherent whole. Including case background information, observations and relevant professional literature, case theory presents an accurate and cogent comprehension of the client Two …


An Investigation Into The Use Of The Virtual Reality Modelling Language (Vrml) As A Means Of Distribution Virtual Reality Tourist Information Across The World Wide Web, Hugh Mcatamney, Ciaran Mcdonnell May 1999

An Investigation Into The Use Of The Virtual Reality Modelling Language (Vrml) As A Means Of Distribution Virtual Reality Tourist Information Across The World Wide Web, Hugh Mcatamney, Ciaran Mcdonnell

Conference papers

The purpose of the work described was to investigate the use of the Virtual Reality Modelling Language (VRML) as a tool to distribute tourist information across the web. This was done by the creation of a web site containing two Virtual Reality models of tourist interest. These were then valuated using a number of techniques both online and offline. This paper describes the methods used to create and evaluate these models as well as giving a overview of some of the results obtained.


Laboratory Testing And Analysis Of Joints For Rigid Pavements, Chelliah Madasamy, Issam E. Harik, David L. Allen, L. John Fleckenstein May 1999

Laboratory Testing And Analysis Of Joints For Rigid Pavements, Chelliah Madasamy, Issam E. Harik, David L. Allen, L. John Fleckenstein

Kentucky Transportation Center Research Report

The primary objective of this study was to analyze the concrete pavement system under nonlinear temperature distribution and vehicle wheel loading. The jointed concrete pavement system consists of concrete slabs with transverse and longitudinal joints, dowel bars (across transverse joints), tie bars (across longitudinal joints), subbase and subgrade soil. Under the loading conditions the pavement structural system may fail by cracking of the concrete slab, loss-of-support of slab due to temperature induced curling, closing and opening of joints, and failure of load transfer devices such as dowel bars, etc. In order to understand the cause of these failures or to …


Small Extensions Of Witt Rings, Robert W. Fitzgerald May 1999

Small Extensions Of Witt Rings, Robert W. Fitzgerald

Articles and Preprints

We consider certain Witt ring extensions S of a noetherian Witt ring R obtained by adding one new generator. The conditions on the new generator are those known to hold when R is the Witt ring of a Field F, S is the Witt ring of a Field K and K/F is an odd degree extension. We show that if R is of elementary type then so is S.


Investment In Minority-Owned Media: A Social Investor’S Perspective, Lloyd Kurtz May 1999

Investment In Minority-Owned Media: A Social Investor’S Perspective, Lloyd Kurtz

Federal Communications Law Journal

Access to capital for minority media remains problematic in the pension and mutual fund world, even among those organizations that practice "socially responsible" investing. The reasons for this include the behavior traits of all institutional investors and the relatively undeveloped state of socially responsible investing. However, modern social research suggests that large media conglomerates, such as Disney, Time-Warner, and Viacom, might be potentially approachable sources of capital for minority media.

Forum: New Approaches to Minority Media Ownership, Columbia Institute for Tele-Information, Columbia University.