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2003

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Articles 3331 - 3360 of 3876

Full-Text Articles in Physical Sciences and Mathematics

Seafloor Segmentation Based On Bathymetric Measurements From Multibeam Echosounders Data, Yuri Rzhanov, Randy G. Cutter Jr., Larry A. Mayer Jan 2003

Seafloor Segmentation Based On Bathymetric Measurements From Multibeam Echosounders Data, Yuri Rzhanov, Randy G. Cutter Jr., Larry A. Mayer

Center for Coastal and Ocean Mapping

Bathymetric data depicts the geomorphology of the seabottom and allows characterization of spatial distributions of apparent benthic habitats. The variability of seafloor topography can be defined as a texture. This prompts for the application of well developed image processing techniques for automatic delineation of regions with clucially different physiographic characteristics. In the present paper histograms of biologically motivated invariant image attributes are used for characterization of local geomorphological feahires. This technique can be naturally applied in a range of spatial scales. Local feature vectors are then submitted to a procedure which divides the set into a number of clusters each …


Mapping And Characterizing Subtidal Oyster Reefs Using Acoustic Techniques, Underwater Videography And Quadrat Counts, Raymond E. Grizzle, J R. Adams, Semme J. Dijkstra, Brian Smith, R W. Ward Jan 2003

Mapping And Characterizing Subtidal Oyster Reefs Using Acoustic Techniques, Underwater Videography And Quadrat Counts, Raymond E. Grizzle, J R. Adams, Semme J. Dijkstra, Brian Smith, R W. Ward

Center for Coastal and Ocean Mapping

Populations of the eastern oyster Crassostrea virginica have been in long-term decline in most areas. A major hindrance to effective oyster management has been lack of a methodology for accurately and economically obtaining data on their distribution and abundance patterns. Here, we describe early results from studies aimed at development of a mapping and monitoring protocol involving acoustic techniques, underwater videography, and destructive sampling (excavated quadrats). Two subtidal reefs in Great Bay, New Hampshire, were mapped with side-scan sonar and with videography by systematically imaging multiple sampling cells in a grid covering the same areas. A single deployment was made …


The Grounding Of An Ice Shelf In The Central Arctic Ocean: A Modeling Experiment, Martin Jakobsson, M Siegert, Mark Paton Jan 2003

The Grounding Of An Ice Shelf In The Central Arctic Ocean: A Modeling Experiment, Martin Jakobsson, M Siegert, Mark Paton

Center for Coastal and Ocean Mapping

A numerical ice sheet model was used in a first test towards evaluating the hypothesis that, during a period of large-scale glaciation, an ice shelf emanating from the Barents/Kara Seas grounded across parts of the Lomonosov Ridge to a depth of around 1000 m below present sea level (Jakobsson, 1999; Polyak et al., 2001). Despite that we not include complex ice shelf physics or grounding line mechanics in our model and treat the process of marine melting in a simple manner, our experiments are the necessary first steps toward providing a comprehensive reconstruction of the former ice-sheet/ice-shelf system in the …


Stone Coalgebras, Clemens Kupke, Alexander Kurz, Yde Venema Jan 2003

Stone Coalgebras, Clemens Kupke, Alexander Kurz, Yde Venema

Engineering Faculty Articles and Research

In this paper we argue that the category of Stone spaces forms an interesting base category for coalgebras, in particular, if one considers the Vietoris functor as an analogue to the power set functor. We prove that the so-called descriptive general frames, which play a fundamental role in the semantics of modal logics, can be seen as Stone coalgebras in a natural way. This yields a duality between the category of modal algebras and that of coalgebras over the Vietoris functor. Building on this idea, we introduce the notion of a Vietoris polynomial functor over the category of Stone spaces. …


A Guide To Prairie And Wetland Restoration In Eastern Nebraska, Gerry Steinauer, Bill Whitney, Krista Adams, Mike Bullerman, Chris Helzer Jan 2003

A Guide To Prairie And Wetland Restoration In Eastern Nebraska, Gerry Steinauer, Bill Whitney, Krista Adams, Mike Bullerman, Chris Helzer

Nebraska Game and Parks Commission: White Papers, Conference Presentations, and Manuscripts

This publication documents the restoration methods originally developed by Bill Whitney and later refined by himself and other ecologists from TNC, PRCT, NGPC and USFWS working in eastern Nebraska. Restoration of the following plant community types is covered in this document: tallgrass prairie, mixed-grass prairie, sand prairie, freshwater wet meadow and marsh, Rainwater Basin wet meadow and marsh, and saline wet meadow and marsh.

The methods we use are generally affordable and not complicated. To quickly summarize, we handpick and machine harvest seed, do little seed cleaning and broadcast plant with a fertilizer spreader. We do not mow annual weeds …


Fourth Kenneth C. Schraut Memorial Lecture (Poster), University Of Dayton. Department Of Mathematics Jan 2003

Fourth Kenneth C. Schraut Memorial Lecture (Poster), University Of Dayton. Department Of Mathematics

Kenneth C. Schraut Memorial Lectures

No abstract provided.


Ideals, Varieties, And Groebner Bases, Joyce Christine Ahlgren Jan 2003

Ideals, Varieties, And Groebner Bases, Joyce Christine Ahlgren

Theses Digitization Project

The topics explored in this project present and interesting picture of close connections between algebra and geometry. Given a specific system of polynomial equations we show how to construct a Groebner basis using Buchbergers Algorithm. Gröbner bases have very nice properties, e.g. they do give a unique remainder in the division algorithm. We use these bases to solve systems of polynomial quations in several variables and to determine whether a function lies in the ideal.


Taxonomy Of Synchronization And Barrier As A Basic Mechanism For Building Other Synchronization From It, Pauline Braginton Jan 2003

Taxonomy Of Synchronization And Barrier As A Basic Mechanism For Building Other Synchronization From It, Pauline Braginton

Theses Digitization Project

A Distributed Shared Memory(DSM) system consists of several computers that share a memory area and has no global clock. Therefore, an ordering of events in the system is necessary. Synchronization is a mechanism for coordinating activities between processes, which are program instantiations in a system.


The Value Of Outdoor Education, Heriberto Garcia Jan 2003

The Value Of Outdoor Education, Heriberto Garcia

Theses Digitization Project

The purpose of this project was to explore the benefits of how students who are exposed to outdoor activities can enhance their attention span, learning, and understanding of the content subjects.


Littlebee: User's Online Interactive Design Of Baby's Wear, Yan Hai Jan 2003

Littlebee: User's Online Interactive Design Of Baby's Wear, Yan Hai

Theses Digitization Project

The purpose of this project is to develop a web-based application called Littlebee that allows customers to do online design of babies' wear. The online designing options include combining appliques with clothing styles and changing fabric colors; it utilizes images pre-stored in the database.


A Tabular Propositional Logic: And/Or Table Translator, Chen-Hsiu Lee Jan 2003

A Tabular Propositional Logic: And/Or Table Translator, Chen-Hsiu Lee

Theses Digitization Project

The goal of this project is to design a tool to help users translate any logic statement into Disjunctive Normal Form and present the result as an AND/OR TABLE, which makes the logic relation easier to express by using a two-dimensional grid of values or expressions. This tool is implemented through a web-based and Java-based application. Thus, the user can utilize this tool via World Wide Web.


Simulation Of Soil Water Movement Model (Swamm) Using The Spider Distributed System, Li Wang Jan 2003

Simulation Of Soil Water Movement Model (Swamm) Using The Spider Distributed System, Li Wang

Theses Digitization Project

This project implements a real application on the Spider II, which is a simulation of Soil Water Movement Model. The main objectives of this project were to develop a parallel and distributed algorithm for the Soil Water Model; implement the Soil Water Movement Simulation model on the Spider II distributed system and to evaluate the performance of simulating the Soil Water Movement Model on Spider II.


The Lakes And Streams Project: A Curriculum For Elementary And Middle Grades On A Local Environmental Issue, Linda Mae Alice Gregory Jan 2003

The Lakes And Streams Project: A Curriculum For Elementary And Middle Grades On A Local Environmental Issue, Linda Mae Alice Gregory

Theses Digitization Project

This project covers the environmental issues of the proposed Lakes and Streams Project for the City of San Bernardino. The water history of San Bernardino, from the hot springs to the development of the current municipal water system, is also detailed. Two curriculum units teach students how to use environmental issue analysis skills. One focuses on the water history of San Bernardino and is aimed at grades three to five. The other immerses middle grade students directly into the Lakes and Streams issue.


White Board, Getahun Alemu Jan 2003

White Board, Getahun Alemu

Theses Digitization Project

This project designs and implements a tool to enhance the current means of availing coursework information in educational systems.


Mona Lake Watershed Resource Atlas, Annis Water Resources Institute Jan 2003

Mona Lake Watershed Resource Atlas, Annis Water Resources Institute

Scientific Technical Reports

Contains:

Mona Lake Watershed Reference Map

Transportation Map

Political Units Map

HydrographyMap

Subbasins Map

Aerial Photography Mosaic – Mona Lake Watershed Map

Total Property Tax Base Map

Digital Elevation Model Map

Land Use/Cover Type Definitions

Land Use and Cover Map - 1978

Land Use and Cover Map - 1997

Land Use and Cover Change Analysis

Percent Impervious by Subbasin Map

Wetlands Map

Presettlement Landscape Map

Population Density Map

Trout Streams and Lakes Map

Water Sources of Mona Lake Map

Groundwater Stream Base Flow Map

Natural Runoff Potential Map

Sheet and Rill Erosion Potential Map

Total Phosphorus Concentration Map

Bacterial Contamination …


Modeling Of Hysteresis And Magnetization Curves For Hexagonally Ordered Electrodeposited Nanowires, Petru S. Fodor, Georgy M. Tsoi, Lowell E. Wenger Jan 2003

Modeling Of Hysteresis And Magnetization Curves For Hexagonally Ordered Electrodeposited Nanowires, Petru S. Fodor, Georgy M. Tsoi, Lowell E. Wenger

Physics Faculty Publications

A computational model has been developed to investigate how the magnetostatic interactions affect the hysteresis and magnetization curves for hexagonal arrays of magnetic nanowires. The magnetization coupling between nanowires arises from the stray fields produced by the other nanowires composing the array such that the field at each nanowire is the sum of the external field and the interaction field with the other nanowires. Using only two adjustable parameters: the interaction between nearest neighbors and the width of the Gaussian distribution in switching fields centered around the measuredcoercivity, simulations are compared with the experimentally measuredhysteresis and magnetization curves for electrodepositedCo0.45 …


Zero Magnetization States In Electrodeposited Co0.45fe0.55 Nanowire Arrays, Petru S. Fodor, Georgy M. Tsoi, Lowell E. Wenger Jan 2003

Zero Magnetization States In Electrodeposited Co0.45fe0.55 Nanowire Arrays, Petru S. Fodor, Georgy M. Tsoi, Lowell E. Wenger

Physics Faculty Publications

Co0.45Fe0.55 alloy nanowires with 12 to 35 nm diameter and 12 μm length were fabricated by electrodeposition in porous anodic alumina templates. The initial magnetization curves reveal that the zero magnetization state is not unique and is determined by the field history (acdemagnetization process) leading to the zero average moment state. For acdemagnetization processes with the field applied parallel to the nanowire axis, the subsequent magnetization curves suggest that an individual nanowire behaves as a single domain with neighboring nanowires being antiparallel to each other in the zero magnetization state. However, for a demagnetization process with the field applied perpendicular …


Collision Cross Sections And The Size Of A Coin, Antonio C. Santos, A. Fröhlich Jan 2003

Collision Cross Sections And The Size Of A Coin, Antonio C. Santos, A. Fröhlich

Physics Faculty Research & Creative Works

An important question in education nowadays is how to convey some concepts of Modern Physics to students in high school, secondary education or the sixth form. This article presents an approach to atomic collisions suitable for intermediate level students. We describe an alternative way of measuring the area of a coin using a macroscopic analogy of the scattering of radiation by an atom or molecule—the collision cross section. We hope this article will help educators to illustrate such an important procedure and related concepts of Modern Physics. © 2003 IOP Publishing Ltd.


Doubly Differential Measurements For Multiple Ionization Of Argon By Electron Impact: Comparison With Positron Impact And Photoionization, Antonio C. Santos, Ahmad Hasan, T. Yates, Robert D. Dubois Jan 2003

Doubly Differential Measurements For Multiple Ionization Of Argon By Electron Impact: Comparison With Positron Impact And Photoionization, Antonio C. Santos, Ahmad Hasan, T. Yates, Robert D. Dubois

Physics Faculty Research & Creative Works

Doubly differential cross sections for single and multiple ionization of Ar have been measured for 500, 750, and 1000 eV electron impact. the cross sections were measured as a function of projectile energy loss and scattering angle. the energy loss range was 0–85 % of the initial projectile energy and scattering angles were between [Formula Presented] the data were put on an absolute scale by normalizing to total ionization cross sections available in the literature and found to be in good agreement with the absolute electron impact cross sections from DuBois and Rudd. for 750 eV impact, a comparison was …


High Precision Wavelength Measurements Of Qed-Sensitive Forbidden Transitions In Highly Charged Argon Ions, I. Draganić, J. R. Crespo López-Urrutia, Robert D. Dubois, S. Fritzsche, V. M. Shabaev, R. Soria Orts, I. I. Tupitsyn, Y. Zou, J. Ullrich Jan 2003

High Precision Wavelength Measurements Of Qed-Sensitive Forbidden Transitions In Highly Charged Argon Ions, I. Draganić, J. R. Crespo López-Urrutia, Robert D. Dubois, S. Fritzsche, V. M. Shabaev, R. Soria Orts, I. I. Tupitsyn, Y. Zou, J. Ullrich

Physics Faculty Research & Creative Works

We present the results of an experimental study of magnetic dipole ([Formula presented]) transitions in highly charged argon ions (ArX, ArXI, ArXIV, ArXV) in the visible spectral range using an electron beam ion trap. their wavelengths were determined with, for highly charged ions, unprecedented accuracy up to the sub-ppm level and compared with theoretical calculations. the QED contributions, calculated in this Letter, are found to be 4 orders of magnitude larger than the experimental error and are absolutely indispensable to bring theory and experiment to a good agreement. This method shows great potential for the study of QED effects in …


Target Z Dependence And Additivity Of Cross Sections For Electron Loss By 6-Mev/Amu [Formula Presented] Projectiles, R. L. Watson, Yong Peng, V. Horvat, G. J. Kim, Ronald E. Olson Jan 2003

Target Z Dependence And Additivity Of Cross Sections For Electron Loss By 6-Mev/Amu [Formula Presented] Projectiles, R. L. Watson, Yong Peng, V. Horvat, G. J. Kim, Ronald E. Olson

Physics Faculty Research & Creative Works

The dependence of electron loss by 6-MeV/amu Xe18+ on target atomic number was investigated by measuring single-collision cross sections for loss of one to eight electrons in targets of the noble gases He, Ne, Ar, Kr, and Xe. the total-electron-loss cross sections were found to increase linearly with target atomic number, but an abrupt slope change was observed to occur between Ne and Kr. Calculated total-loss cross sections obtained using the n-body classical trajectory Monte Carlo method were in good agreement with the measurements. the dependence of the individual cross sections on the number of electrons lost was reasonably …


Superfluorescence Polarization: Signature Of Collisional Redistribution, A. Kumarakrishnan, S. Chudasama, Xianming Han Jan 2003

Superfluorescence Polarization: Signature Of Collisional Redistribution, A. Kumarakrishnan, S. Chudasama, Xianming Han

Scholarship and Professional Work - LAS

We have studied effects of magnetic sublevel degeneracy on the polarization of superfluorescent pulses generated on the Ca 4s4p1P1–3d4s1D2 transition at 5.5μm. These pulses were generated from a cell of length 50 cm by optically pumping calcium vapor on the 4s21S0–4s4p1P1 transition in the presence of Ar gas. The axis of ellipticity of superfluorescence (SF) polarization is oriented parallel to the axis of the pump-laser polarization at large detunings, and undergoes an abrupt rotation through 90° for detunings close to resonance. The distribution of populations in the magnetic sublevels of the 1P1 state can be estimated using a simple model …


A Solvent-Free Claisen Condensation Reaction For The Organic Laboratory, John J. Esteb, Matthew B. Stockton Jan 2003

A Solvent-Free Claisen Condensation Reaction For The Organic Laboratory, John J. Esteb, Matthew B. Stockton

Scholarship and Professional Work - LAS

An experiment involving the Claisen condensation reaction for a first-year organic chemistry laboratory is presented. Claisen condensations are routinely covered in organic textbooks but owing to the long reaction times required to reach equilibrium in solution they are seldom explored in the undergraduate teaching laboratory. In this experiment, potassium tert-butoxide and ethyl phenylacetate are heated to 100 °C for 30 minutes under solvent-free conditions to produce 2,4-diphenyl acetoacetate in 80% yield. The solvent-free nature of this procedure greatly reduces the quantity of waste generated by students relative to typical carbonyl condensation experiments.


Victim Characteristics And Victim Impact Evidence In South Carolina Capital Cases, Theodore Eisenberg, Stephen P. Garvey, Martin T. Wells Jan 2003

Victim Characteristics And Victim Impact Evidence In South Carolina Capital Cases, Theodore Eisenberg, Stephen P. Garvey, Martin T. Wells

Cornell Law Faculty Publications

The use of victim impact evidence (VIE) has been a standard feature of capital trials since 1991, when the Supreme Court lifted the previously existing constitutional bar to such evidence. Legal scholars have almost universally condemned the use of VIE, criticizing it on a variety of grounds. Yet little empirical analysis exists that examines how VIE influences the course and outcome of capital trials. We analyze the influence of VIE based on interviews with over two-hundred jurors who sat on capital trials in South Carolina between 1985 and 2001.

First, we describe the VIE introduced at sentencing trials, using a …


Nullification At Work? A Glimpse From The National Center For State Courts Study Of Hung Juries, Paula Hannaford-Agor, Valerie P. Hans Jan 2003

Nullification At Work? A Glimpse From The National Center For State Courts Study Of Hung Juries, Paula Hannaford-Agor, Valerie P. Hans

Cornell Law Faculty Publications

In recent years, the criminal justice community has become increasingly concerned about the possibility that jury nullification is the underlying motivation for increasing numbers of acquittals and mistrials due to jury deadlock in felony jury trials. In this Article, the authors discuss the inherent difficulty in defining jury nullification and identifying its occurrence in actual trials. They review the evolution in public and legal opinion about the legitimacy of jury nullification and contemporary judicial responses to perceived instances of jury nullification. Finally, the authors examine the possible presence of jury nullification through empirical analysis of data collected from 372 felony …


Identification Of Gypsy Moth Defoliation In Ohio Using Landsat Data, Angela Lorraine Hurley Jan 2003

Identification Of Gypsy Moth Defoliation In Ohio Using Landsat Data, Angela Lorraine Hurley

Browse all Theses and Dissertations

The gypsy moth is one of the most devastating forest pests in North America. In late spring, gypsy moth larvae hatch from eggs laid the previous summer. During the next forty days, tens of thousands of these caterpillars eat up to one square foot of foliage each. The gypsy moth has established populations in several states, and dangerously fast-growing populations in several others. The state of Ohio is a critical area in the suppression of the gypsy moth because the front of gypsy moth advance passes through the state. Besides diminishing the aesthetic value of Ohio’s forests, gypsy moths also …


2003 File Geodatabase Containing Aerial Photos, Pete Reehling, Richard Mckenzie, City Of Tampa Department Of Sanitary Sewers Bay Study Group Jan 2003

2003 File Geodatabase Containing Aerial Photos, Pete Reehling, Richard Mckenzie, City Of Tampa Department Of Sanitary Sewers Bay Study Group

Images

The Bay Study Group was created by the City of Tampa in 1976 to monitor the effects of pollution abatement that occurred in Hillsborough Bay when the city’s wastewater treatment plant was upgraded from primary to advanced treatment in 1979. The Bay Study Group documented a remarkable restoration of water quality parameters and biological indicators in Hillsborough Bay from the mid 1980s until 2009, when it was disbanded. This zip Geodatabase file contains the aerial photos for the year 2003.


Computing Answer Sets Of A Logic Program Via-Enumeration Of Sat Certificates, Yuliya Lierler, Marco Maratea Jan 2003

Computing Answer Sets Of A Logic Program Via-Enumeration Of Sat Certificates, Yuliya Lierler, Marco Maratea

Computer Science Faculty Proceedings & Presentations

Answer set programming is a new programming paradigm proposed based on the answer set semantics of Prolog. It is well known that an answer set for a logic program is also a model of the program's completion. The converse is true when the logic program is "tight". Lin and Zhao showed that for non-tight programs the models of completion which do not correspond to answer sets can be eliminated by adding to the completion what they called "loop formulas". Nevertheless, their solver ASSAT 1 has some disadvantages: it can work only with basic rules, and it can compute only one …


Simplicity Of Ultragraph Algebras, Mark Tomforde Jan 2003

Simplicity Of Ultragraph Algebras, Mark Tomforde

Dartmouth Scholarship

In this paper we analyze the structure of C*-algebras associated to ultragraphs, which are generalizations of directed graphs. We characterize the simple ultragraph algebras as well as deduce necessary and sufficient conditions for an ultragraph algebra to be purely infinite and to be AF. Using these techniques we also produce an example of an ultragraph algebra which is neither a graph algebra nor an Exel-Laca algebra. We conclude by proving that the C*-algebras of ultragraphs with no sinks are Cuntz-Pimsner algebras.


Effect Of Geochemical Processes And Environment On The Spatial Pattern Of Selenium In Soil, Surface Water, And Groundwater At The Hovland Ranch, Central South Dakota, Salah U. Sharif Jan 2003

Effect Of Geochemical Processes And Environment On The Spatial Pattern Of Selenium In Soil, Surface Water, And Groundwater At The Hovland Ranch, Central South Dakota, Salah U. Sharif

Theses and Dissertations

The objective of this paper is to test and review some of the published hypotheses as that may relate to selenium geochemistry in soil and water system at the Hovland Ranch, Haakon County, South Dakota. Representative samples were collected from soil, water, and soil moisture in the field. Preparation of samples and chemical analysis were done in the Water Quality Laboratory, Dept. of Geology and Geological Engineering, University of North Dakota and Human Nutrition Research Center Lab, USDA/ARS, Grand Forks, North Dakota. The analysis results were statistically analyzed to find correlation between the occurrence of selenium and other associated chemical …