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2002

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Articles 2101 - 2130 of 3435

Full-Text Articles in Physical Sciences and Mathematics

Magnetic Moment And Anisotropy In Fencom Clusters, J. Kortus, T. Baruah, M. R. Pederson, C. Ashman, Shiv N. Khanna Jan 2002

Magnetic Moment And Anisotropy In Fencom Clusters, J. Kortus, T. Baruah, M. R. Pederson, C. Ashman, Shiv N. Khanna

Physics Publications

Electronic structure calculations of FenCom (n+m=5 and 13) are used to examine the effects of alloying on the magnetic moment and magnetic anisotropies. Our density-functional studies show that many mixed clusters have moments comparable to or higher than the pure clusters. The mixed clusters, however, have very low anisotropies and could be ideal as soft magnetic materials. It is shown that shape, composition, and compositional ordering must be considered for optimization of anisotropy energies.

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Applications Of Graph Theory To Separability, Stephen Young Jan 2002

Applications Of Graph Theory To Separability, Stephen Young

Mathematical Sciences Technical Reports (MSTR)

Let S be a surface with a triangular tiling T. Let R be a reflection a side of one of the triangles; so that R is an orientation reversing isometry of the surface. Define M = {s in S |S : Rs = s}. We then say that the surface S separates along the reflection R if S-R has two components. This paper considers the applications of graph theoretic methods to determining whether a reflection is separating or not and compares the algorithmic efficiency of these methods to the current known methods.

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On Size Mappings, W. J. Charatonik, Alicja Samulewicz Jan 2002

On Size Mappings, W. J. Charatonik, Alicja Samulewicz

Mathematics and Statistics Faculty Research & Creative Works

A real-valued mapping r from the hyperspace of all compact subsets of a givenmetric space X is called a size mapping if r({x}) = 0 for x ∈ X and r(A) ≤ r(B) if a ⊂ B. We investigate what continua admit an open or a monotone size mapping. Special attention is paid to the diameter mappings.

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Status Of Coral Reefs In The Us Caribbean And Gulf Of Mexico: Florida, Texas, Puerto Rico, Us Virgin Islands And Navassa, Billy Causey, Joanne Delaney, Ernesto Diaz, Richard E. Dodge, Jorge R. Garcia, Jamie Higgins, Walter Jaap, Cruz A. Matos, George P. Schmahl, Caroline Rogers, Margaret W. Miller, Donna D. Turgeon Jan 2002

Status Of Coral Reefs In The Us Caribbean And Gulf Of Mexico: Florida, Texas, Puerto Rico, Us Virgin Islands And Navassa, Billy Causey, Joanne Delaney, Ernesto Diaz, Richard E. Dodge, Jorge R. Garcia, Jamie Higgins, Walter Jaap, Cruz A. Matos, George P. Schmahl, Caroline Rogers, Margaret W. Miller, Donna D. Turgeon

Marine & Environmental Sciences Faculty Reports

The following report on the status of US Caribbean coral reef ecosystems has been summarised from more extensive reports submitted to the US Coral Reef Task Force (USCRTF) working group that implemented in 2000 ‘A National Program to Assess, Inventory, and Monitor US Coral Reef Ecosystems’. The more-lengthy reports are also the basis for the biennial-issued document, ‘Status and Trends of US Coral Reef Ecosystems’. Each author is a recognised technical expert with responsibility for monitoring and/or managing aspects of their respective coral reef ecosystems.

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Chiasmodontidae: Swallowers., J. D. Mceachran, Tracey Sutton Jan 2002

Chiasmodontidae: Swallowers., J. D. Mceachran, Tracey Sutton

Marine & Environmental Sciences Faculty Reports

No abstract provided.

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Sea Turtle Conservation Program, Broward County, Fl 2002 Report, Curtis M. Burney, Stefanie Ouellette Jan 2002

Sea Turtle Conservation Program, Broward County, Fl 2002 Report, Curtis M. Burney, Stefanie Ouellette

Marine & Environmental Sciences Faculty Reports

No abstract provided.

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Boater Manatee Awareness System, Edward O. Keith Jan 2002

Boater Manatee Awareness System, Edward O. Keith

Marine & Environmental Sciences Faculty Reports

A variety of "see-in-the-dark" technologies have been evaluated with the objective of adapting them to detect Florida manatee (Trichechus manatus latirostris) aggregations in specific highuse areas, such as warm water refuges in the winter time. Once it is possible to passively detect manatee aggregations in these sites, the construction of boater awareness signs that would indicate how many manatees are in the area, on a real-time basis, is envisioned. The contention is that boaters would be more likely to obey speed restrictions if these restrictions were accompanied by this type of information. The ability to do this also …

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On Quadrature Rules Associated With Appell Polynomials, Gabriella Bretti, Matthew He, Paolo E. Ricci Jan 2002

On Quadrature Rules Associated With Appell Polynomials, Gabriella Bretti, Matthew He, Paolo E. Ricci

Mathematics Faculty Articles

A quadrature rule using Appell polynomials and generalizing both the Euler-MacLaurin quadrature formula and a similar quadrature rule, obtained in Bretti et al [15], which makes use of Euler (instead of Bernoulli) numbers and even (instead of odd) derivatives of the given function at the extrema of the considered interval, is derived. An expression of the remainder term and a numerical example are also enclosed.

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Winter 2002, Nsu Oceanographic Center Jan 2002

Winter 2002, Nsu Oceanographic Center

Currents

No abstract provided.

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Recent Applications Of Flame Atomic Absorption Spectrometry To Environmental Measurements, Michael A. Janusa Jan 2002

Recent Applications Of Flame Atomic Absorption Spectrometry To Environmental Measurements, Michael A. Janusa

Faculty Publications

Atomic absorption spectroscopy is very useful for the determination of a large number of elements, especially at trace levels. It is a widely used technique for analysis of a wide variety of sample matrices including biota, soils, and water. Atomic absorption spectroscopy is a very reputable technique that is inexpensive and delivers accurate results even in a complex matrix. This review focuses on the applications of flame atomic absorption spectroscopy to environmental measurements, and is mainly based on papers published from 1999–2002.

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Soil Leachate Responses During 10 Years Of Induced Whole-Watershed Acidification, Pamela J. Edwards, James N. Kochenderfer, Dean W. Coble, Mary Beth Adams Jan 2002

Soil Leachate Responses During 10 Years Of Induced Whole-Watershed Acidification, Pamela J. Edwards, James N. Kochenderfer, Dean W. Coble, Mary Beth Adams

Faculty Publications

Soil solution was collected from zero-tension lysimeters for 10 yr on two small central Appalachian watersheds in West Virginia, U.S.A. Ammonium sulfate fertilizer was applied to one catchment 3 times per year during each year. The other watershed was used as a reference to account for ambient baseline conditions. Ca and Mg concentrations collected below the A- and B-horizons of the treated watershed increased and then decreased over time as a result of the treatment. By contrast, Ca and Mg concentrations in the C-horizon continued to increase throughout the study period.

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Dynamic Traffic Grooming Algorithms For Reconfigurable Sonet Over Wdm Networks, Shu Zhang, Byrav Ramamurthy Jan 2002

Dynamic Traffic Grooming Algorithms For Reconfigurable Sonet Over Wdm Networks, Shu Zhang, Byrav Ramamurthy

CSE Conference and Workshop Papers

The emergence of Wavelength Division Multiplexing (WDM) technology provides the capability for increasing the bandwidth of Synchronous Optical Network (SONET) rings by grooming low-speed traffic streams onto different high-speed wavelength channels. Since the cost of SONET add-drop multiplexers (SADM) at each node dominates the total cost of these networks, how to assign the wavelength, groom in the traffic and bypass the traffic through the intermediate nodes has received a lot of attention from researchers recently.

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Selected Reflection Imaging: A Useful Tool For Imaging Nanocomposite Magnetic Materials, Yi Liu, Y. Qiang, M. Yu, J. Ping Liu, David J. Sellmyer Jan 2002

Selected Reflection Imaging: A Useful Tool For Imaging Nanocomposite Magnetic Materials, Yi Liu, Y. Qiang, M. Yu, J. Ping Liu, David J. Sellmyer

David Sellmyer Publications

The great strength of transmission electron microscope (TEM) is its capability to access to both real space (imaging) and reciprocal space (diffraction). Selected reflection imaging (SRI) can relate the diffraction of nanostructured materials with the image, providing information otherwise not possible. The experimental set up of SRI is given by Liu and Sellmyer [I]. In this paper we present some new measurements on nanocomposite magnetic materials.

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A Procedural Evaluation Of An Analytic-Deliberative Process: The Columbia River Comprehensive Impact Assessment, Aimee Guglielmo Kinney, Thomas M. Leschine Jan 2002

A Procedural Evaluation Of An Analytic-Deliberative Process: The Columbia River Comprehensive Impact Assessment, Aimee Guglielmo Kinney, Thomas M. Leschine

US Army Corps of Engineers

The U.S. Department of Energy's Columbia River Comprehensive Impact Assessment (CRCIA) was an ambitious attempt to direct its cleanup of the Hanford Nuclear Reservation toward the most significant risks to the Columbia River resulting from past plutonium production. DOE's approach was uncommonly open, including tribal, regulatory agency, and other Hanford interest group representatives on the board that was to develop the assessment approach. The CRCIA process had attributes of the ``analytic-deliberative'' process for risk assessment recommended by the National Research Council. Nevertheless, differences between the DOE and other participants over what was meant by the term ``comprehensive'' in the group's …

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Future Antarctic Margin Drilling: Developing A Science Program Plan For Mcmurdo Sound -- Report Of A Workshop Oxford, Uk April 5–7, 2001, David M. Harwood, Laura Lacy, Richard Levy Jan 2002

Future Antarctic Margin Drilling: Developing A Science Program Plan For Mcmurdo Sound -- Report Of A Workshop Oxford, Uk April 5–7, 2001, David M. Harwood, Laura Lacy, Richard Levy

ANDRILL Research and Publications

ANDRILL (ANtarctic DRILLing) is a multinational initiative with the objectives to recover stratigraphic core records for use in interpreting Antarctica’s climatic, glacial and tectonic history over the past 50 million years and at varying scales of age resolution (0.1 to 100 thousand years [k.y.]). A key motivation of ANDRILL is that the role of the Antarctic cryosphere (ice sheets, ice shelves and sea-ice) in the global climate system is complex and poorly known. Understanding the past history of ice volume variation in Antarctica and associated physical changes in this region is critical to proper assessment of the global climate system …

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Tws Wildlife Damage Management Working Group Newsletter: Summer 2002 – Volume 9(2) Jan 2002

Tws Wildlife Damage Management Working Group Newsletter: Summer 2002 – Volume 9(2)

TWS Wildlife Damage Management Working Group Newsletter

Forward; Wanted: Information On Management Of Coyotes In Urban/Suburban Locals; Candidates For The Working Group Officers – July 2002; Wildlife Damage Management Working Group Ballot – July 2002; Book Review - Resolving Human-Wildlife Conflicts: The Science Of Wildlife Damage Management

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Implications Of Single-Particle Experiments For Track Theory, Therapy And Radiation Protection, Robert Katz, Francis Cucinotta Jan 2002

Implications Of Single-Particle Experiments For Track Theory, Therapy And Radiation Protection, Robert Katz, Francis Cucinotta

Robert Katz Publications

‘‘Because the predominant exposure of cells in humans is to single isolated tracks, a critical question is what effects a single track is capable of producing and with what probabilities.’’ ‘‘Most of the current biophysical models. . . make the clear prediction that a single track can produce virtually all of the detrimental stochastic effects of interest.’’ ‘‘But one model, in particular (the amorphous track model of Katz and coworkers), disagrees fundamentally that a single low LET track has the ability to cause the cellular changes.’’ ‘‘This model leads to very dramatic differences in the predicted risk at low doses. …

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Holographic Recording Of Fast Events On A Ccd Camera, Zhiwen Liu, Martin Centurion, George Panotopoulos, John Hong, Demetri Psaltis Jan 2002

Holographic Recording Of Fast Events On A Ccd Camera, Zhiwen Liu, Martin Centurion, George Panotopoulos, John Hong, Demetri Psaltis

Martin Centurion Publications

We report on holographic recording of nanosecond events on a conventional CCD camera. Three frames of an air-discharge event, with resolution of 5.9 ns and frame interval of 12 ns, are recorded in a single CCD frame. Each individual frame is reconstructed by digital filtering of the CCD frame, since successively recorded holograms are centered at different carrier frequencies in the spatial frequency domain.

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Human Population And Freshwater Resources: U.S. Cases And International Perspectives, Karin M. Krchnak, Victoria Dompka Markham, Nancy Thorne Jan 2002

Human Population And Freshwater Resources: U.S. Cases And International Perspectives, Karin M. Krchnak, Victoria Dompka Markham, Nancy Thorne

Yale School of the Environment Bulletin Series

No abstract provided.

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Developing Industrial Ecosystems: Approaches, Cases, And Tools, Marian Chertow, Michelle Portlock Jan 2002

Developing Industrial Ecosystems: Approaches, Cases, And Tools, Marian Chertow, Michelle Portlock

Yale School of the Environment Bulletin Series

No abstract provided.

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Global Environmental Governance: Options & Opportunities, Daniel C. Esty, Maria H. Ivanova Jan 2002

Global Environmental Governance: Options & Opportunities, Daniel C. Esty, Maria H. Ivanova

Yale School of the Environment Publications Series

No abstract provided.

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Accuracy, Resolution And Stability Properties Of A Modified Chebyshev Method, Jodi Mead, Rosemary A. Renaut Jan 2002

Accuracy, Resolution And Stability Properties Of A Modified Chebyshev Method, Jodi Mead, Rosemary A. Renaut

Mathematics Faculty Publications and Presentations

While the Chebyshev pseudospectral method provides a spectrally accurate method, integration of partial differential equations with spatial derivatives of order M requires time steps of approximately O(N−2M) for stable explicit solvers. Theoretically, time steps may be increased to O(N−M) with the use of a parameter, α-dependent mapped method introduced by Kosloff and Tal-Ezer [ J. Comput. Phys., 104 (1993), pp. 457–469]. Our analysis focuses on the utilization of this method for reasonable practical choices for N, namely N ≲ 30, as may be needed for two- or three dimensional modeling. Results presented …

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Early Cretaceous Normal Faulting In Southern New England: Evidence From Apatite And Zircon Fission-Track Ages, Mary K. Roden-Tice, Robert P. Wintsch Jan 2002

Early Cretaceous Normal Faulting In Southern New England: Evidence From Apatite And Zircon Fission-Track Ages, Mary K. Roden-Tice, Robert P. Wintsch

Mary K. Roden-Tice

New apatite and zircon fission‐track (AFT, ZFT) ages from Mesozoic sediments and adjacent crystalline rocks from southern New England reveal age gradients from Middle Jurassic to Early Cretaceous. These gradients reflect the rotation of crustal blocks after the setting of the youngest AFT ages (∼140 Ma). The AFT ages of 168–98 Ma for 32 samples of Paleozoic metamorphic rocks east and west and within the Hartford Basin of Massachusetts and Connecticut indicate that unroofing in these regions occurred from Late Jurassic through Early Cretaceous. In both the Hartford Basin and rocks from crystalline terranes east of the basin, AFT ages …

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Nullspace Composition Of Control Laws For Grasping, Robert Platt, Andrew Fagg, Roderic Grupen Jan 2002

Nullspace Composition Of Control Laws For Grasping, Robert Platt, Andrew Fagg, Roderic Grupen

Roderic Grupen

Much of the tradition in robot grasping is rooted in geometrical, planning-based approaches in which it assumed that object and finger geometries are well modeled a priori. Some recent approaches have chosen instead to deal with objects of unknown geometry. These techniques treat grasping as an active sensory-driven problem. At any given time, finger contacts are incrementally displaced along the objects local surface using a single control law. In this paper, we extend this approach by allowing multiple control laws to be active simultaneously. Three control laws are combined by projecting the actions of subordinate control laws into other control …

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Transform-Invariant Image Decomposition With Similarity Templates, Chris Stauffer, Erik Learned-Miller, Kinh Tieu Jan 2002

Transform-Invariant Image Decomposition With Similarity Templates, Chris Stauffer, Erik Learned-Miller, Kinh Tieu

Erik G Learned-Miller

Recent work has shown impressive transform-invariant modeling and clustering for sets of images of objects with similar appearance. We seek to expand these capabilities to sets of images of an object class that show considerable variation across individual instances (e.g. pedestrian images) using a representation based on pixel-wise similarities, similarity templates. Because of its invariance to the colors of particular components of an object, this representation enables detection of instances of an object class and enables alignment of those instances. Further, this model implicitly represents the regions of color regularity in the class-specific image set enabling a decomposition of that …

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Automatic Segmentation And Indexing Of Specialized Databases, Madirakshi Das, R. Manmatha Jan 2002

Automatic Segmentation And Indexing Of Specialized Databases, Madirakshi Das, R. Manmatha

R. Manmatha

The aim of this work is to index images based on color, in domain specific databases using colors computed from the object of interest only, instead of using the whole image. The main problem in this task is the segmentation of the region of interest from the background. Viewing segmentation as a figure/ground segregation problem leads to a new approach--successful elimination of the background leaves the figure or object of interest. The background elements are eliminated using general observations true for any photograph where there is a single, prominent object of interest. First, we form a hypothesis about possible background …

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Modeling Score Distributions For Meta Search, R. Manmatha, T. Rath, F. Feng Jan 2002

Modeling Score Distributions For Meta Search, R. Manmatha, T. Rath, F. Feng

R. Manmatha

In this paper the score distributions of a number of text search engines are modeled. It is shown empirically that the score distributions on a per query basis may be modeled using an exponential distribution for the set of non-relevant documents and a normal distribution for the set of relevant documents. Experiments show that this model fits TREC-3 and TREC-4 data for a wide variety of different search engines including INQUERY a probabilistic search engine, SMART a vector space engine, and search engines based on latent semantic indexing and language modeling. The model also works when search engines index other …

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Multispectrum, Spatially Addressable Polarization Interference Filter, Salman Saeed, Philip Bos Jan 2002

Multispectrum, Spatially Addressable Polarization Interference Filter, Salman Saeed, Philip Bos

Philip J. Bos

We review current synthesis techniques for generating and improving birefringent filters. The relationship between wave-plate orientation and the resulting spectral output is shown to be that of a simple Fourier transform. By using this relationship and starting from the fan Sole configuration, we easily generated plate orientations providing lower sidelobe levels and improved finesse. We outline a method by which filters can be constructed to provide from 0 to 100% of the desired passband in a continuous fashion. Such a filter can be stacked to allow rapid control of any number of passbands and is shown, as an example in …

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Laplace Transform Of Spherical Bessel Functions, Andrei Ludu Jan 2002

Laplace Transform Of Spherical Bessel Functions, Andrei Ludu

Andrei Ludu

No abstract provided.

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Oral History Interview With Jim Gray, Philip L. Frana Jan 2002

Oral History Interview With Jim Gray, Philip L. Frana

Philip L Frana

Gray discusses his childhood in Rome and education at the University of California, Berkeley. He explains the influence of Sputnik, Norbert Wiener's view of cybernetics and society, the social impact of computing, and the artificial intelligence papers of Newell and Simon in the shaping of his career. Gray describes his co-op position at General Dynamics, as well as positions with Bell Labs (Murray Hill) and IBM Research in Yorktown Heights and San Jose. Gray also describes his evaluations of computer models stimulated by the ...

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