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1997

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Articles 451 - 480 of 2472

Full-Text Articles in Physical Sciences and Mathematics

37. Masao Horio 1905-1996, Otto Vogl, Masahide Yamamoto Sep 1997

37. Masao Horio 1905-1996, Otto Vogl, Masahide Yamamoto

Otto Vogl

No abstract provided.


Preservation Of The Range Under Perturbations Of An Operator, Branko Ćurgus, Branko Najman Sep 1997

Preservation Of The Range Under Perturbations Of An Operator, Branko Ćurgus, Branko Najman

Mathematics Faculty Publications

A sufficient condition for the stability of the range of a positive operator in a Hilbert space is given. As a consequence, we get a class of additive perturbations which preserve regularity of the critical point 0 of a positive operator in a Krein space.


Defining And Refining Frameless Rendering, Ellen J. Scher Zagier Sep 1997

Defining And Refining Frameless Rendering, Ellen J. Scher Zagier

Link Foundation Modeling, Simulation and Training Fellowship Reports

Frame1ess Rendering (FR) is a rendering paradigm which performs stochastic temporal filtering by updating pixels in a random order, based on most recent available input data, and displaying them to the screen immediately (3]. It has inherent in its design, visual artifacts that come across as "spatial scatter''. Due to the asynchronicity of pixel updates, a noisy or "scattered" image is perceived if the update rate is not fast enough. We describe the fac1ors that influence the perceptual quality when Frarneless Rendering is implemented such as object and viewpoint velocities, pattern and object size, and pattern and object separation. The …


Distributed Collaborative Learning Environments, Mark C. Kilby Sep 1997

Distributed Collaborative Learning Environments, Mark C. Kilby

Link Foundation Modeling, Simulation and Training Fellowship Reports

The evolution of technologies for the World Wide Web (WWW), computer-supported cooperative work (CSCW) and distributed simulation provides new opportunities for education delivery as well as unique perspectives for training. Simulation follows a learn-by-doing philosophy . The WWW and CSCW provides a collaborative learning perspective by encouraging collective knowledge building. By merging these two approaches, Distributed Collaborative Learning Environments (DCLEs) can be developed to provide new approaches to training in the military, industry, and academia. Traditional approaches toward educational rely on an information transfer model. Instructors deliver the material to the students and students are tested on how well they …


Legendrian Circular Helix Links, Lisa Traynor Sep 1997

Legendrian Circular Helix Links, Lisa Traynor

Mathematics Faculty Research and Scholarship

Examples are given of legendrian links in the manifold of cooriented contact elements of the plane, or equivalently, in the 1-jet space of the circle which are not equivalent via an isotopy of contact diffeomorphisms. These examples have generalizations to linked legendrian spheres in contact manifolds diffeomorphic to R-n x Sn-1. These links are distinguished by applying the theory of generating functions to contact manifolds.


Wright State University College Of Engineering And Computer Science Bits And Pcs Newsletter, Volume 13, Number 7, September 1997, College Of Engineering And Computer Science, Wright State University Sep 1997

Wright State University College Of Engineering And Computer Science Bits And Pcs Newsletter, Volume 13, Number 7, September 1997, College Of Engineering And Computer Science, Wright State University

BITs and PCs Newsletter

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


Solitary Waves And Atomic Population Transfer Via The Continuum, Foek T. Hioe, C. E. Carroll Sep 1997

Solitary Waves And Atomic Population Transfer Via The Continuum, Foek T. Hioe, C. E. Carroll

Physics Faculty/Staff Publications

Exact analytic results are presented that represent a pair of solitary waves that can propagate through an atomic medium with their shapes invariant while producing transfer of atoms or molecules from one bound state to another via a continuum. The speed of the waves and the amount of population transfer are given in terms of the wave amplitudes. A general ~not solitary wave! solution for the case of a single wave is presented, together with a nonlinear Beer’s law of absorption.


On The Product Of Two Generalized Derivations, Mohamed Barraa, Steen Pedersen Sep 1997

On The Product Of Two Generalized Derivations, Mohamed Barraa, Steen Pedersen

Mathematics and Statistics Faculty Publications

Two elements A and B in a ring R determine a generalized derivation deltaA,B on R by setting δA,B(X) = AX - XA for any X in R. We characterize when the product δC,DδA,B is a generalized derivation in the cases when the ring R is the algebra of all bounded operators on a Banach space epsilon, and when R is a C*-algebra U. We use the se characterizations to compute the commutant of the range of δA,B.


Hydrocarbon Ions In The Ionosphere Of Titan, Jane L. Fox, Roger V. Yelle Sep 1997

Hydrocarbon Ions In The Ionosphere Of Titan, Jane L. Fox, Roger V. Yelle

Physics Faculty Publications

We have constructed a new model of the ionosphere of Titan that includes 67 species and 626 reactions. Although N2+ is the major ion produced over most of the ionosphere, the ionization flows to ions whose parent neutrals have lower ionization potentials and to ions formed from species with large proton affinities. In contrast to other models, which have predicted that HCNH+ should be the major ion, our calculations suggest that the major ions at and below the ion peak are hydrocarbon ions, and H, C, and N-containing ions. Our predicted peak electron density for a solar …


Issues Affecting Western Australia's Inshore Crab Fishery Blue Swimmer Crab (Portunus Pelagicus) Sand Crab (Ovalipes Australiensis), Cathy Cambell Sep 1997

Issues Affecting Western Australia's Inshore Crab Fishery Blue Swimmer Crab (Portunus Pelagicus) Sand Crab (Ovalipes Australiensis), Cathy Cambell

Fisheries management papers

This paper is designed to inform the general public about the issues and management options for managing the State's blue swimmer and sand crab fishery.


High Quality Interfaces In Gaas-Alas Quantum Wells Determined From High Resolution Photoluminescence, D. C. Reynolds, David C. Look, B. Jogai, R. Kaspi, K. R. Evans, M. Estes Sep 1997

High Quality Interfaces In Gaas-Alas Quantum Wells Determined From High Resolution Photoluminescence, D. C. Reynolds, David C. Look, B. Jogai, R. Kaspi, K. R. Evans, M. Estes

Physics Faculty Publications

No abstract provided.


Is Accurate Understanding Of Global Warming Necessary To Promote Willingness To Sacrifice?, Richard J. Bord, Ann Fisher, Robert E. O'Connor Sep 1997

Is Accurate Understanding Of Global Warming Necessary To Promote Willingness To Sacrifice?, Richard J. Bord, Ann Fisher, Robert E. O'Connor

RISK: Health, Safety & Environment (1990-2002)

Although not definitive, the authors' study suggests potential benefits from having a general public better informed about global climate change. They find, e.g., that accurate information appears to increase willingness to accept personal sacrifice.


Book Review Of Deborah G. Mayo, Error And The Growth Of Experimental Knowledge (University Of Chicago Press 1996), Kristin S. Shrader-Frechette Sep 1997

Book Review Of Deborah G. Mayo, Error And The Growth Of Experimental Knowledge (University Of Chicago Press 1996), Kristin S. Shrader-Frechette

RISK: Health, Safety & Environment (1990-2002)

Review of the book: Deborah G. Mayo, Error and the Growth of Experimental Knowledge (University of Chicago Press 1996). Figures, index, preface, references. ISBN 0-226-51197-9 [493 pp. $74.00 Cloth; $29.95 Paper. 5801 S. Ellis Ave., Chicago, IL 60637.]


A Football Chase On Video, Norman F. Derby, Robert Fuller, Thomas A. Summers Sep 1997

A Football Chase On Video, Norman F. Derby, Robert Fuller, Thomas A. Summers

Robert G. Fuller Publications

At some universities, football examples are used to motivate students in physics courses to study the law of kinematics and collisions. (In fact, it has been rumored that the number of such examples is inversely related the national ranking of the local football team.) In addition, pursuit-and-evasion strategies are often introduced in beginning calculus courses as a device for teaching mathematical modeling and problem solving. Some recent papers describe theoretical strategies for pursuit-and-evasion that are appropriate for a one-on-one situation in a football game. But what do players actually do in a real football game? We decided to look into …


Quantum Coulomb Glass Within A Hartree-Fock Approximation, Frank Epperlein, Michael Schreiber, Thomas Vojta Sep 1997

Quantum Coulomb Glass Within A Hartree-Fock Approximation, Frank Epperlein, Michael Schreiber, Thomas Vojta

Physics Faculty Research & Creative Works

We study the influence of electron-electron interactions on the electronic properties of disordered materials. In particular, we consider the insulating side of a metal-insulator transition where screening breaks down and the electron-electron interaction remains long ranged. The investigations are based on the quantum Coulomb glass, a generalization of the classical Coulomb glass model of disordered insulators. The quantum Coulomb glass is studied by decoupling the Coulomb interaction by means of a Hartree-Fock approximation and exactly diagonalizing the remaining localization problem. We investigate the behavior of the Coulomb gap in the density of states when approaching the metal-insulator transition and study …


Post-Rendering 3d Image Warping, William R. Mark Sep 1997

Post-Rendering 3d Image Warping, William R. Mark

Link Foundation Modeling, Simulation and Training Fellowship Reports

A pair of rendered images and their Z-buffers contain almost all of the information necessary to re-render from nearby viewpoints. For the small changes in viewpoint that occur in a fraction of a second, this information is sufficient for high quality re-rendering with cost independent of scene complexity. Re-rendering from previously computed views allows an order-of-magnitude increase in apparent frame rate over that provided by conventional rendering alone. It can also compensate for system latency in local or remote display. We use McMillan and Bishop's image warping algorithm to re-render, allowing us to compensate for viewpoint translation as well as …


The Prairie Naturalist Volume 29, No.3. September 1997 Sep 1997

The Prairie Naturalist Volume 29, No.3. September 1997

The Prairie Naturalist

FISHING STATISTICS IN KANSAS PUT-AND-TAKE RAINBOW TROUT FISHERIES ▪ R. D. Schultz and D. D. Nygren

DISTRIBUTIONAL STATUS Of UNCOMMON FISHES AND AN AMPHIBIAN FROM NORTHEASTERN MISSOURI ▪ R. A. Hrabik,

DIET OF A RELICT POPULATION OF THE EASTERN WOODRAT IN NEBRASKA ▪ H. H. Genoways, P. W Freeman, and M. K. Clausen

ANIMAL SPECIES MONITORED BY THE SOUTH DAKOTA NATURAL HERITAGE PROGRAM ▪ E. D. Stukel and D. C. Backlund

Dedication

Announcements


Asymptotics Of Zeros Of Relativistic Hermite Polynomials, Matthew He, K. Pan, Paolo E. Ricci Sep 1997

Asymptotics Of Zeros Of Relativistic Hermite Polynomials, Matthew He, K. Pan, Paolo E. Ricci

Mathematics Faculty Articles

The relativistic Hermite polynomial (RHP) is a class of orthogonal polynomials associated with varying weights. We study the asymptotics of the zeros of the RHP when both degree $n$ of polynomials and relativistic parameter $N$ approach infinity.


Remanence Enhancement And Exchange Coupling In Prco/Co Films, J. Ping Liu, Yi Liu, Z.S. Shan, David J. Sellmyer Sep 1997

Remanence Enhancement And Exchange Coupling In Prco/Co Films, J. Ping Liu, Yi Liu, Z.S. Shan, David J. Sellmyer

David Sellmyer Publications

PrCo/Co multilayer thin films have been prepared by sputtering. After heat treatment, high coercivity is developed and the remanence is enhanced for the insertion of the CO layers and the exchange coupling between the hard phase and the soft phase, which leads to high energy products of the composite magnets. The nanostructure of the films has been studied by TEM. It is found that the grain size of the films with high energy products is in the range from 10 to 25 nanometers.


Information Retrieval On The World Wide Web, Venkat N. Gudivada, Vijay V. Raghavan, William I. Grosky, Rajesh Kasanagottu Sep 1997

Information Retrieval On The World Wide Web, Venkat N. Gudivada, Vijay V. Raghavan, William I. Grosky, Rajesh Kasanagottu

Computer Science Faculty Research & Creative Works

Effective search and retrieval are enabling technologies for realizing the full potential of the Web. The authors examine relevant issues, including methods for representing document content. They also compare available search tools and suggest methods for improving retrieval effectiveness.


From Contemporary Workflow Process Automation To Adaptive And Dynamic Work Activity Coordination And Collaboration, Amit P. Sheth Sep 1997

From Contemporary Workflow Process Automation To Adaptive And Dynamic Work Activity Coordination And Collaboration, Amit P. Sheth

Kno.e.sis Publications

The article outlines a research agenda for researchers in the area of workflow. We believe that today's workflow systems should evolve to what is termed as work coordination and collaboration systems (WCCSs). A WCCS will: (a) adapt to various changes in the organization (including its interactions with external organizations) and the organizational processes by being able to change the process definitions as well as change the processes and component activities while they are being enacted or executed; and (b) support a unified framework for managing coordination, collaboration, and information based decision making activities that naturally occur as part of organizational …


Defect Donor And Acceptor In Gan, David C. Look, D. C. Reynolds, Joseph W. Hemsky, J. R. Sizelove, R. L. Jones, Richard J. Molnar Sep 1997

Defect Donor And Acceptor In Gan, David C. Look, D. C. Reynolds, Joseph W. Hemsky, J. R. Sizelove, R. L. Jones, Richard J. Molnar

Physics Faculty Publications

No abstract provided.


Lamb Shift Of 3p And 4p States And The Determination Of Α, Ulrich D. Jentschura, Gerhard Soff, Peter J. Mohr Sep 1997

Lamb Shift Of 3p And 4p States And The Determination Of Α, Ulrich D. Jentschura, Gerhard Soff, Peter J. Mohr

Physics Faculty Research & Creative Works

The fine-structure interval of P states in hydrogenlike systems can be determined theoretically with high precision, because the energy levels of P states are only slightly influenced by the structure of the nucleus. Therefore a measurement of the fine structure may serve as an excellent test of QED in bound systems, or alternatively as a means of determining the fine-structure constant a with very high precision. In this paper an improved analytic calculation of higher-order binding corrections to the one-loop self-energy of 3P and 4P states in hydrogenlike systems with a low nuclear charge number Z is presented. The method …


Geology Of The Ponca Creek And Keya Paha River Drainage Basins In Nebraska, Robert F. Diffendal Jr. Sep 1997

Geology Of The Ponca Creek And Keya Paha River Drainage Basins In Nebraska, Robert F. Diffendal Jr.

Robert F. Diffendal, Jr., Publications

The geology of the study area has been investigated many times over more than a century. Interested readers are directed to the report by Diffendal and Voorhies (1994), which gives a more detailed overview of the results of the investigations and lists most of the more important reports about the area’s geology.

The names of the sedimentary rock strata and unlithified sediments exposed in and underlying all or parts of the study area are shown in Table V.I. These formations range in age from more than 85 million years to sediments being deposited today by winds, water, and downslope movements …


A Comparison Of Movements And Burrow Usage Between Indigenous And Relocated Gopher Tortoises (Gopherus Polyphemus) In A Fall Line Sandhills Community, Dorinda Morpeth Sep 1997

A Comparison Of Movements And Burrow Usage Between Indigenous And Relocated Gopher Tortoises (Gopherus Polyphemus) In A Fall Line Sandhills Community, Dorinda Morpeth

Theses and Dissertations

The movements and burrow use of twenty (ten relocated and ten indigenous to the relocation site) adult gopher tortoises {Gopherus polyphemus) were followed during the late spring, summer and early autumn in Talbot County, Georgia. The objectives of this study were to determine whether relocated gopher tortoises developed fidelity to a relocation site, and whether indigenous tortoises reacted adversely to relocated tortoises released in their proximity. Ten tortoises in the right-of-way of a highway construction project were captured, fitted with transmitters, and relocated to a 336 hectare tract of land, 3.2 km east of Geneva, Talbot, County, Georgia. Concurrently, ten …


X-Ray-Absorption Spectral Study Of The R₂Fe₁₇₋ₓmₓ Solid Solutions (R=Ce, Nd And M=Al, Si), Denis Vandormael, Fernande Grandjean, Valérie Briois, D. P. Middleton, K. H. Buschow, Gary J. Long Sep 1997

X-Ray-Absorption Spectral Study Of The R₂Fe₁₇₋ₓmₓ Solid Solutions (R=Ce, Nd And M=Al, Si), Denis Vandormael, Fernande Grandjean, Valérie Briois, D. P. Middleton, K. H. Buschow, Gary J. Long

Chemistry Faculty Research & Creative Works

The x-ray-absorption near-edge structure (XANES) spectra obtained at the cerium LIII edge of the Ce2Fe17-xAlx solid solutions and Ce2Fe14Si3, show two absorption peaks characteristic of the 4f1 and 4f0 configurations of cerium, peaks which indicate that cerium is in a mixed valent state in these compounds. All the XANES spectra have been consistently and excellently fit with one sigmoidal function and two Gaussianbroadened Lorentzian functions. The cerium spectroscopic valence obtained from the relative areas of the two peaks decreases from 3.64 to 3.43 between x=0 and …


Nonlinear Front Evolution Of Hydrodynamic Chemical Waves In Vertical Cylinders, J. W. Wilder, D. A. Vasquez, Boyd F. Edwards Sep 1997

Nonlinear Front Evolution Of Hydrodynamic Chemical Waves In Vertical Cylinders, J. W. Wilder, D. A. Vasquez, Boyd F. Edwards

All Physics Faculty Publications

The nonlinear stability of three-dimensional reaction-diffusion fronts in vertical cylinders is considered using the viscous hydrodynamic fluid equations in the limit of infinite thermal diffusivity. A nonlinear front evolution equation is presented and used to examine the transition from nonaxisymmetric to axisymmetric convection observed in experiments performed in cylinders. Comparisons with experiments show excellent agreement in both the shape and speed of the front.


Center For Sustainable Agricultural Systems Newsletter, September/October 1997 Sep 1997

Center For Sustainable Agricultural Systems Newsletter, September/October 1997

Center for Sustainable Agricultural Systems: Newsletters (1993-2000)

Contents:

Linking Ecology and Agriculture to Increase Sustainability

California Salad and Australian Emu in Nebraska?

The State of Rural America: We Can Choose Our Future

Seeking K-16 Curriculum Volunteers

Impact Project Deadlines


Gravity And Bf Theory Defined In Bounded Regions, V. Husain, Seth Major Sep 1997

Gravity And Bf Theory Defined In Bounded Regions, V. Husain, Seth Major

Articles

We study Einstein gravity in a finite spatial region. By requiring a well-defined variational principle, we identify all local boundary conditions, derive surface observables, and compute their algebra. The observables arise as induced surface terms, which contribute to a non-vanishing Hamiltonian. Unlike the asymptotically flat case, we find that there are an infinite number of surface observables. We give a similar analysis for SU(2) BF theory.


Study Of The Effects Of Initial-Bred Nuclei On Zeolite Naa Crystallization By Quasi-Elastic Light Scattering Spectroscopy And Electron Microscopy, Leszek Gora, Kiril A. Streletzky, Robert W. Thompson, George D.J. Phillies Sep 1997

Study Of The Effects Of Initial-Bred Nuclei On Zeolite Naa Crystallization By Quasi-Elastic Light Scattering Spectroscopy And Electron Microscopy, Leszek Gora, Kiril A. Streletzky, Robert W. Thompson, George D.J. Phillies

Physics Faculty Publications

Synthesis studies have been conducted at 25, 60, and 80 °C with a clear solution batch composition that produces zeolite NaA. Aluminosilicate precursor material was added to promote the synthesis and to evaluate the effects of adding initial-bred nuclei that were created by a precursor “seed” reaction. It is shown that the initial-bred nuclei promoted the crystallization rate, that the crystalline mass produced was increased when using the initial-bred nuclei, and that the nucleation of a second population was not inhibited by the addition of initial-bred nuclei as seeds.