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2002

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Articles 751 - 780 of 3435

Full-Text Articles in Physical Sciences and Mathematics

Electron Correlation Leading To Double-K-Shell Vacancy Production In Li-Like Ions Colliding With Helium, Ali Sami Alnaser Aug 2002

Electron Correlation Leading To Double-K-Shell Vacancy Production In Li-Like Ions Colliding With Helium, Ali Sami Alnaser

Dissertations

Single and double K-shell vacancies in Li-like ions colliding with neutral helium target have been investigated using high-resolution Auger projectile spectroscopy. Be+, B2+, C3+, and O5+ Li-like ions were produced and accelerated to intermediate-to-high collision velocities where perturbative models are expected to be valid, using the Tandem Van de Graaff accelerator at Western Michigan University. Double-K-shell vacancies in atomic systems or so-called “ hollow ions” can be induced by different mechanism in ion-atom collisions. For intermediate-to-high velocity collisions where the collision time is small, the projectile ion can interact with only one of …


A New Type Of Particle Detector For Nuclear Scattering Experiments, Philip Ugorowski Aug 2002

A New Type Of Particle Detector For Nuclear Scattering Experiments, Philip Ugorowski

Dissertations

A new detector was needed for counting recoil protons resulting from proton-proton (pp) elastic scattering during pion production experiments by the Polarized Internal Target Experiments (PINTEX) group at Indiana University Cyclotron Facility (IUCF). The previous silicon detectors were only usable forincoming protons up to 9 MeV, and a stopping power of at least 40 MeV was needed. In addition, the detector had to operate in nanotorr vacuum, and near strong varying magnetic fields, ruling out standard organic plastic scintillators and photomultiplier tubes. We needed to find the most suitable inorganic scintillator and another method of detecting the photons produced when …


Scalable And Reliable File Transfer For Clusters Using Multicast., Hardik Dikpal Shukla Aug 2002

Scalable And Reliable File Transfer For Clusters Using Multicast., Hardik Dikpal Shukla

Electronic Theses and Dissertations

A cluster is a group of computing resources that are connected by a single computer network and are managed as a single system. Clusters potentially have three key advantages over workstations operated in isolation—fault tolerance, load balancing and support for distributed computing.

Information sharing among the cluster’s resources affects all phases of cluster administration. The thesis describes a new tool for distributing files within clusters. This tool, the Scalable and Reliable File Transfer Tool (SRFTT), uses Forward Error Correction (FEC) and multiple multicast channels to achieve an efficient reliable file transfer, relative to heterogeneous clusters. SRFTT achieves scalability …


Integrated Software System For The Collection And Evaluation Of Wellness Information., Rebecca Elizabeth Sweeney Aug 2002

Integrated Software System For The Collection And Evaluation Of Wellness Information., Rebecca Elizabeth Sweeney

Electronic Theses and Dissertations

There is an absence of a complete, easy to use, software system that can evaluate all areas of wellness. Although there are software programs and equipment available to examine certain aspects of wellness, they are incomplete. The solution to the difficulties of assessing wellness is the design and development of a software system that can be used to collect and evaluate wellness information. The system allows for complete reporting as it entails the six major components to wellness: demographics, body composition, lab work, nutritional intake, physical activity, and body measures. The system allows for ease of use by providing a …


Fisheries Research Report No. 132 - A Review Of Food Availability, Sea Water Characteristics And Bivalve Growth Performance At Coastal Culture Sites In Temperate And Warm Temperate Regions Of The World, Sidney A. Saxby Aug 2002

Fisheries Research Report No. 132 - A Review Of Food Availability, Sea Water Characteristics And Bivalve Growth Performance At Coastal Culture Sites In Temperate And Warm Temperate Regions Of The World, Sidney A. Saxby

Fisheries research reports

The suitability of a coastal area for bivalve farming, as well as the density at which bivalves can be farmed in that area, is limited by the available food supply and other environmental variables. In this review, a range of successful and marginal bivalve growing areas in temperate and warm temperate coastal areas around the world are characterised. These include areas of high food and nutrient levels, such as Saldanha Bay in South Africa, and the Seto Inland Sea, Japan, through to more oligotrophic areas, typified by parts of the South Australian coastline and the Mediterranean Sea. The latter areas …


Wide Binary Systems And The Nature Of High-Velocity White Dwarfs, Nicole M. Silvestri, Terry D. Oswalt, Suzanne L. Hawley Aug 2002

Wide Binary Systems And The Nature Of High-Velocity White Dwarfs, Nicole M. Silvestri, Terry D. Oswalt, Suzanne L. Hawley

Aerospace, Physics, and Space Science Faculty Publications

We present measured radial velocities and complete space motions for 116 white dwarf stars with M dwarf companions. Thirteen pairs have " halo-like " velocities. According to a recent study by Oppenheimer et al., all these high-velocity white dwarfs should be considered part of the dark matter heavy halo of the Galaxy, based on their kinematics. Based on the near-solar abundance levels of the M dwarf companions, we conclude that 12 of our 13 high-velocity white dwarfs are actually part of the high-velocity tail of the thick disk, rather than the dark matter halo of the Galaxy, in agreement with …


An Ecosystem Dynamics Model Of Monterey Bay, California, Lawrence S. Klein Aug 2002

An Ecosystem Dynamics Model Of Monterey Bay, California, Lawrence S. Klein

Electronic Theses and Dissertations

Monterey Bay is an upwelling region with high biological productivity in the California Coastal Current System. Several moorings, developed and maintained by the Monterey Bay Aquarium Research Institute (MBARI), have produced a long-term, highquality time series oceanographic data set for the Monterey Bay. The data set has revealed a more comprehensive picture of physical-biological interaction on seasonal and interannual variability. To improve our understanding of how the marine ecosystem responds to physical forcing, especially upwelling, an open ocean ecosystem model was modified for the Monterey Bay upwelling region. The result was a nine-component ecosystem model of Monterey Bay, which produced …


Corrosion Of Steel By Lead Bismuth Eutectic: Quarterly Report For May-June-July 2002, John Farley Aug 2002

Corrosion Of Steel By Lead Bismuth Eutectic: Quarterly Report For May-June-July 2002, John Farley

Transmutation Sciences Materials (TRP)

The goal of this project is to understand the basic science of corrosion in the steel/LBE system.

We are taking more data, typically using the newly installed X-ray Photoelectron Spectrometry (XPS) apparatus, and analyzing our existing data. Undergraduate students Denise Parsons and Julia Manzerova have helped a great deal in the analysis of the data. We can obtain the elemental composition as a function of position within the sample. This gives clues to the migration of materials, the composition of the protective oxide layer, and the basic science of the corrosion process. We found dramatic differences between the exposed and …


Dose Coefficient (Dc) Methodology Report, John P. Shanahan, Phillip W. Patton, Mark Rudin Aug 2002

Dose Coefficient (Dc) Methodology Report, John P. Shanahan, Phillip W. Patton, Mark Rudin

Transmutation Sciences Physics (TRP)

The purpose of this report is to present the methodology developed to calculate internal and external dose coefficients for radionuclides produced in the spallation process. Much of the information regarding computer codes in this report comes from various technical manuals and professional papers. References are provided at the beginning of each section for documentation and for the user who requires more specific information. The report also includes the results of applying the methodology to determine dose coefficients for five radionuclides. This effort identified potential areas of concern that will need to be addressed when the methodology is used in the …


Poiseuille Advection Of Chemical Reaction Fronts, Boyd F. Edwards Aug 2002

Poiseuille Advection Of Chemical Reaction Fronts, Boyd F. Edwards

All Physics Faculty Publications

Poiseuille flow between parallel plates alters the shapes and velocities of chemical reaction fronts. In the narrow-gap limit, the cubic reaction-diffusion-advection equation predicts a front-velocity correction equal to the gap-averaged fluid velocity ϵ. In the singular wide-gap limit, the correction equals the midgap fluid velocity 3ϵ/2 when the flow is in the direction of propagation of the reaction front, and equals zero for adverse flow of any amplitude for which the front has a midgap cusp. Stationary fronts are possible only for adverse flow and finite gaps. Experiments are suggested.


Simulations Of The Instability Of The M = 1 Self-Shielding Diocotron Mode In Finite-Length Non-Neutral Plasmas, Grant W. Mason, Ross L. Spencer Aug 2002

Simulations Of The Instability Of The M = 1 Self-Shielding Diocotron Mode In Finite-Length Non-Neutral Plasmas, Grant W. Mason, Ross L. Spencer

Faculty Publications

The "self-shielding" m = 1 diocotron mode in Malmberg-Penning traps has been known for over a decade to be unstable for finite length non-neutral plasmas with hollow density profiles. Early theoretical efforts were unsuccessful in accounting for the exponential growth and/or the magnitude of the growth rate. Recent theoretical work has sought to resolve the discrepancy either as a consequence of the shape of the plasma ends or as a kinetic effect resulting from a modified distribution function as a consequence of the protocol used to form the hollow profiles in experiments. Both of these finite length mechanisms have been …


Dsc Analysis Of Rectangular Plates With Non-Uniform Boundary Conditions, Yibao Zhao, G. W. Wei Aug 2002

Dsc Analysis Of Rectangular Plates With Non-Uniform Boundary Conditions, Yibao Zhao, G. W. Wei

Research Collection Lee Kong Chian School Of Business

This paper introduces the discrete singular convolution (DSC) for the vibration analysis of rectangular plates with non-uniform and combined boundary conditions. A systematic scheme is proposed for the treatment of boundary conditions required in the proposed approach. The validity of the DSC approach for plate vibration is tested by using a large number of numerical examples that have a combination of simply supported, clamped and transversely supported (with non-uniform elastic rotational restraint) edges. The present results are in excellent agreement with those in the literature.


Using The Index Of Biotic Integrity Of Fish Communities To Evaluate Habitat Quality In Middle Chattahoochee River Tributaries, Theodor W. Roever Aug 2002

Using The Index Of Biotic Integrity Of Fish Communities To Evaluate Habitat Quality In Middle Chattahoochee River Tributaries, Theodor W. Roever

Theses and Dissertations

An ichthyological survey was conducted within the lower Piedmont and upper Coastal Plain physiographic regions of the middle Chattahoochee River drainage basin between August 1998 and September 2000. Sampling was conducted by Columbus State University (CSU) under contract to Columbus Water Works for the purpose of obtaining biological measurements of watershed health. Objectives of the survey were the establishment of a data baseline of IBI scores for this ecoregion and to ascertain if there was a correlation between the IBI score and human influence. The thesis to be tested is: 'Fish community IBI scores of different watersheds within the Middle …


Antarctic Notothenioid Fishes Do Not Display Metabolic Cold Adaptation In Hepatic Gluconeogenesis, Leonardo J. Magnoni Aug 2002

Antarctic Notothenioid Fishes Do Not Display Metabolic Cold Adaptation In Hepatic Gluconeogenesis, Leonardo J. Magnoni

Electronic Theses and Dissertations

Antarctic notothenioid fishes present specializations related to their chronically cold environment, such as high lipid content in tissues (predominantly triacylglycerols, TAG). When TAGs are mobilized, they yield fatty acids and glycerol. Fatty acids are the primary fuel of oxidative muscle tissues. Gluconeogenesis from glycerol has not been studied in Antarctic fishes despite the importance of glycerol as a breakdown product of TAGs. To assess the possible importance of glycerol as a substrate for gluconeogenesis and to determine whether this pathway and Krebs cycle are metabolically cold adapted, key hepatic enzyme activities were measured in Antarctic notothenioid fishes (Notothenia coriiceps, Gobionotothen …


A Pilot Study To Test Ventless Traps As A Means To Quantify Populations Of The American Lobster (Homarus Americanus), Carin Louise Poeschel Aug 2002

A Pilot Study To Test Ventless Traps As A Means To Quantify Populations Of The American Lobster (Homarus Americanus), Carin Louise Poeschel

Electronic Theses and Dissertations

The American lobster, Homarus americanus, is Maine's most valuable marine fishery. The state of Maine has an economic interest in the protection of this resource. The health of this industry depends on effective management for sustainability. However, there is little quantitative information on American lobsters less than harvestable size. A study was conducted to evaluate the utility of traps modified to catch sublegal lobsters. With the aid of fishernlen fiom six of the eight Maine coastal counties over a four-month time period (July through October, 2000), data were recorded to compare catch rates in experimental traps with no escape vents …


An Examination Of The Georges River Clam Management Program, Kristin E. Togue Brawn Aug 2002

An Examination Of The Georges River Clam Management Program, Kristin E. Togue Brawn

Electronic Theses and Dissertations

This thesis examines the Georges River Clam Management Program, a multi-town interlocal harvesting and management plan in mid-coast Maine. It discusses relevant economic and communal action theory, and examines their application to the development of the program. Chapter 1 reviews the purposes and methods of the study. Chapter 2 reviews the relevant clam biology necessary to understand the principles of soft-shell clam management. Chapters 3 and 4 provide the history and background of clam harvesting and management in Maine. Chapter 5 discusses the Georges River Program, including the factors that led to its development and the details of its organization …


Numerical Wave Simulations On Different Oceanic Scales, Khalid M. Zubier Aug 2002

Numerical Wave Simulations On Different Oceanic Scales, Khalid M. Zubier

Electronic Theses and Dissertations

In practical applications, numerical wave models are used as reliable tools to provide near future wave predictions and wave climatology for specific region. Obviously models first should go through extensive validation/verification procedures. Once validated, models can be used in scientific applications to investigate methods for improving performance and to develop better understanding of wave associated physical mechanisms and their interactions in specific field experiments. Two wave transformation models, SWAN and CGWAVE, are used to simulate wave conditions at the Field Research Facility, Duck (North Carolina). The motivation is to examine how well these models reproduce observations and to determine the …


Dietary Overlap Between Wolves And Coyotes In Northwestern Montana, Wendy M. Arjo, Daniel H. Pletscher, Robert R. Ream Aug 2002

Dietary Overlap Between Wolves And Coyotes In Northwestern Montana, Wendy M. Arjo, Daniel H. Pletscher, Robert R. Ream

United States Department of Agriculture Wildlife Services: Staff Publications

We studied effects of recolonizing wolves (Canis lupus) in the North Fork of the Flathead area of northwestern Montana on the diets of coyotes (C. latrans) from 1994 to 1997. Wolf and coyote diets differed in frequency of occurrence of prey species during 3 of the 4 summers and winters (P< 0.001) during the study. Coyote diets contained more murid prey items, and wolf diets contained more deer (Odocoileus virginianus and O. hemionus) in the summer and elk (Cervus elaphus) in the winter. Coyotes and wolves ate prey of different size during both the summer (P < 0.001) and winter (P < 0.001) months in 1994– 1996: wolves took a greater proportion (P < 0.001) of large (>45 kg) prey species and coyotes, small (<2 kg) prey (P < 0.001). Wolves selected a larger proportion of adults (P …


The John Muir Newsletter, Fall 2002, The John Muir Center For Environmental Studies Aug 2002

The John Muir Newsletter, Fall 2002, The John Muir Center For Environmental Studies

Muir Center Newsletters (1981-2015)

The John Muir NeWi pr FER UNlVEESnY OF THE PACIFIC, STOCKTON, CA V( ilume 12, Number 4. Fall 2002; John Muir and the Civil War by Millie Stanley 7- suppose you have heard that they have drafted up in Marquette County and will be anxious to hear who are drafted you may be glad you were not taken."l Annie Muir penned these words in November, 1862, to her brother John who was a student at Wisconsin State University in Madison. Two years before, when he was twenty-two years old, John had traveled from his farm home in Marquette County to …


Underwater Video Survey: Planning And Data Processing, Yuri Rzhanov, Lloyd C. Huff, Randy G. Cutter Jr. Aug 2002

Underwater Video Survey: Planning And Data Processing, Yuri Rzhanov, Lloyd C. Huff, Randy G. Cutter Jr.

Center for Coastal and Ocean Mapping

The importance of underwater video surveys as an exploration tool has been steadily increasing over recent years [1]. Better photographic equipment, more effective sources of illumination, and improved processing techniques - all make video surveying a reliable tool for seafloor habitat mapping, sediment boundary delineation and groundtruthing, mapping and documentation of forensic and archaeological sites. There is a change in attitude towards video surveying that affects the way the data is collected, and hence its quality. Earlier video data processing algorithms had to cope with whatever was recorded (often simultaneously with acquisition of other data, considered to be more important). …


The Navigation Surface: A New Database Approach To Creating Multiple Products From High-Density Surveys, Shep M. Smith Lt, Lee Alexander, Andy Armstrong Aug 2002

The Navigation Surface: A New Database Approach To Creating Multiple Products From High-Density Surveys, Shep M. Smith Lt, Lee Alexander, Andy Armstrong

Center for Coastal and Ocean Mapping

High-resolution bathymetric surveys are revolutionising hydrographic surveying. ln addition to safety-of-navigation , there are a host of other uses for high-resolution bathymetry, including habitat mapping, hydrologic modelling, marine archaeology, and marine environmental protection. However, at present, there is no suitable method that can be used to produce multiple products that meet the needs of both navigation customers and other users . A research project conducted at the University of New Hampshire developed a model of the seafloor that is optimised for safety-of-navigation . This new technique bypasses the rather subjective, 'selected soundings' approach. Instead, a statistical model is created directly …


Genesis And Morphology Of Soil Pendants In Quaternary Landforms Of Pahranagat Valley, Nevada, Amy Lynn Brock Aug 2002

Genesis And Morphology Of Soil Pendants In Quaternary Landforms Of Pahranagat Valley, Nevada, Amy Lynn Brock

UNLV Theses, Dissertations, Professional Papers, and Capstones

Five geomorphic surfaces present in the northern Pahranagat Valley, Lincoln County, Nevada range in age from Early Pleistocene to Recent (Q1-Q5) and vary in clast lithology from dolomite to volcanic tephras. Two chronosequences and 5 lithosequences were compared to evaluate micro and macromorphic characteristics and development of soil pendants. This study presents a new interpretation for soil pendant development. Key features observed in the Pahranagat Valley pendants provide evidence for precipitation at the clast-pendant contact suggesting that newer deposits are not always found at the pendant terminus as other studies have assumed. These features include a void at the clast-pendant …


Double-Logarithmic Two-Loop Self-Energy Corrections To The Lamb Shift, Ulrich D. Jentschura, I. Nandori Aug 2002

Double-Logarithmic Two-Loop Self-Energy Corrections To The Lamb Shift, Ulrich D. Jentschura, I. Nandori

Physics Faculty Research & Creative Works

Self-energy corrections involving logarithms of the parameter Z α can often be derived within a simplified approach, avoiding calculational difficulties typical of the problematic nonlogarithmic corrections (as customary in bound-state quantum electrodynamics, we denote by Z the nuclear charge number, and by α the fine-structure constant). For some logarithmic corrections, it is sufficient to consider internal properties of the electron characterized by form factors. We provide a detailed derivation of related self-energy “potentials” that give rise to the logarithmic corrections; these potentials are local in coordinate space. We focus on the double-logarithmic two-loop coefficient B62 for P states and …


The Use Of Native And Modified Cyclodextrins For Method Development In Capillary Electrophoresis And Chemical Sensor Applications, Mustafa Culha Aug 2002

The Use Of Native And Modified Cyclodextrins For Method Development In Capillary Electrophoresis And Chemical Sensor Applications, Mustafa Culha

Doctoral Dissertations

The development and design of novel methods and materials for separation and sensing systems have critical importance for the analysis of complex mixtures. In these systems, molecular recognition is the key element for desired selectivity and it can only be achieved using rationally designed, chemically selective reagents. Cyclodextrins (CDs) are a group of macro-cyclic molecules that can recognize certain analytes depending on their shape and size. In this work, the primary goal was the design and development of CD-based separation and sensing systems. Native and derivatized CDs were utilized to develop methods for separation of a complex mixture containing six …


Availability Of Organochlorides And Accumulation In Populations Of Tadarida Brasiliensis (Free-Tailed Bat) And Eptesicus Fuscus (Big Brown Bat), Michelle Lee Smith Aug 2002

Availability Of Organochlorides And Accumulation In Populations Of Tadarida Brasiliensis (Free-Tailed Bat) And Eptesicus Fuscus (Big Brown Bat), Michelle Lee Smith

Theses and Dissertations

Organochlorides were historically effective in controlling a wide range of pests. However, organochlorides have proved to present many problems to the health and welfare of other organisms. Due to these problems, especially declines in wildlife populations, organochlorides were restricted in the 1970's and a majority of them were banned in the mid to late 1980's. The effects of organochlorides on bats such as Tadarida brasiliensis and Eptesicus fuscus have been intensively studied. The effects can range from problems with reproduction to mortality. My analysis of populations of T. brasiliensis and E. fuscus showed that organochlorides are still present in the …


Simple, Compact Source For Low-Temperature Air Plasmas, D. P. Sheehan, J. Lawson, M. Sosa, R. A. Long Aug 2002

Simple, Compact Source For Low-Temperature Air Plasmas, D. P. Sheehan, J. Lawson, M. Sosa, R. A. Long

Physics and Biophysics: Faculty Scholarship

A simple, compact source of low-temperature, spatially and temporally uniform air plasma using a Telsa induction coil driver is described. The low-power ionization discharge plasma is localized (2 cm X 0.5 cm X 0.1 cm) and essentially free of arc channels. A Teflon coated rolling cylindrical electrode and dielectric coated ground plate are essential to the source’s operation and allow flat test samples to be readily exposed to the plasma. The plasma is a copious source of ozone and nitrogen oxides. Its effects on various microbes are discussed.


Visual Execution Analysis For Multiagent Systems, Chong Kil Aug 2002

Visual Execution Analysis For Multiagent Systems, Chong Kil

Theses and Dissertations

Multiagent systems have become increasingly important in developing complex software systems. Multiagent systems introduce collective intelligence and provide benefits such as flexibility, scalability, decentralization, and increased reliability. A software agent is a high-level software abstraction that is capable of performing given tasks in an environment without human intervention. Although multiagent systems provide a convenient and powerful way to organize complex software systems, developing such system is very complicated. To help manage this complexity this research develops a methodology and technique for analyzing, monitoring and troubleshooting multiagent systems execution. This is accomplished by visualizing a multiagent system at multiple levels of …


Future Directions For Mobile-Agent Research, David Kotz, Robert Gray, Daniela Rus Aug 2002

Future Directions For Mobile-Agent Research, David Kotz, Robert Gray, Daniela Rus

Dartmouth Scholarship

The field of mobile agents should shift its emphasis toward mobile code, in all its forms, rather than continue focusing on mobile agents. The development of modular components will help application designers take advantage of code mobility without having to rewrite their applications to fit in monolithic, mobile agent systems.


Detection Of Slide Transition For Topic Indexing, Chong-Wah Ngo, Ting-Chuen Pong, Thomas S. Huang Aug 2002

Detection Of Slide Transition For Topic Indexing, Chong-Wah Ngo, Ting-Chuen Pong, Thomas S. Huang

Research Collection School Of Computing and Information Systems

This paper presents an automatic and novel approach in detecting the transitions of slides for video sequences of technical lectures. Our approach adopts a foreground vs background segmentation algorithm to separate a presenter from the projected electronic slides. Once a background template is generated, text captions are detected and analyzed. The segmented caption regions as well as background templates together provide salient visual cues to decide whether a slide is flipped and replaced. The partitioning of videos according to slide changes not only structure the content of video according to topics, but also facilitate the synchronization of video, audio and …


Metal Ion Separation Mediated By Organized Molecular Assemblies, Hong Cao Aug 2002

Metal Ion Separation Mediated By Organized Molecular Assemblies, Hong Cao

Masters Theses

We have investigated the separation of Co(II), Ni(II), Cu(II) and Zn(II) by the ligands 8-hydroxyquinoline- 5-sulfonic acid and 7-iodo-8-hydroxy-quinoline- 5-sulfonic acid in the presence of the anionic surfactant sodium dodecyl sulfate (SDS) and the cationic surfactant octyltrimethylammonium bromide (OTAB) . Baseline separations have been achieved by HPLC employing an octadecylsilanized silica (ODS) column. The underlying mechanisms of separation have been determined.

The significant new results of our studies are: (1) separation is not possible without the presence of surfactants and hence organized assemblies; (2) separations can be achieved under submicellar concentrations; (3) the separations are not driven by micelles; and …