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Old Dominion University

1997

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Articles 1 - 30 of 72

Full-Text Articles in Physical Sciences and Mathematics

Data Assimilation Experiments In The Gulf Stream Region: How Useful Are Satellite-Derived Surface Data For Nowcasting The Subsurface Fields?, Tal Ezer, George L. Mellor Dec 1997

Data Assimilation Experiments In The Gulf Stream Region: How Useful Are Satellite-Derived Surface Data For Nowcasting The Subsurface Fields?, Tal Ezer, George L. Mellor

CCPO Publications

Satellite-derived surface data have become an important source of information for studies of the Gulf Stream system. The question of just how useful these datasets are for nowcasting the subsurface thermal fields, however, remains to be fully explored. Three types of surface data-sea surface temperature (SST), sea surface height (SSH), and Gulf Stream position (GSP)-are used here in a series of data assimilation experiments to test their usefulness when assimilated into a realistic primitive equation model. The U.S. Navy's analysis fields from the Optimal Thermal Interpolation System are used to simulate the surface data and to evaluate nowcast errors. Correlation …


Tidally Driven Residual Circulation In Shallow Estuaries With Lateral Depth Variation, Chunyan Li, James O'Donnell Dec 1997

Tidally Driven Residual Circulation In Shallow Estuaries With Lateral Depth Variation, Chunyan Li, James O'Donnell

CCPO Publications

Tidally driven residual circulation in shallow estuaries with lateral depth variation has been studied analytically using a two-dimensional, depth-averaged model. The solution is presented for a v-shaped channel. Exchange flow is found to be correlated with the topography. The magnitude of this exchange flow depends mainly on four parameters: the ratio between the minimum depth on the shoal and the maximum depth in the channel, the ratio between the tidal amplitude at the mouth and the mean depth, the ratio between the length of the estuary and the tidal wave length, and the ratio between the tidal timescale and the …


Corrigendum To “Post-Surgical Passive Response Of Local Environment To Primary Tumor Removal”: Mathl. Comput. Modelling, Vol. 25, No. 6, Pp. 7–17, 1997, J. A. Adam, C. Bellomo Dec 1997

Corrigendum To “Post-Surgical Passive Response Of Local Environment To Primary Tumor Removal”: Mathl. Comput. Modelling, Vol. 25, No. 6, Pp. 7–17, 1997, J. A. Adam, C. Bellomo

Mathematics & Statistics Faculty Publications

The computer program that was used to generate the graphs for the concentration of inhibitor contained an error. This influenced the scaling in the original Figures 2 and 3. As an example, a sample of the corrected graphs are given below. Copies of other corrected figures can be obtained from the authors. It is important to note that the “pulse” appears for the function rC(r, t). As can be seen, it travels slowly outward with decreasing amplitude. The mathematical analysis in the paper remains unchanged.


Vertical Profiles Of Bromoform In Snow, Sea Ice, And Seawater In The Canadian Arctic, William T. Sturges, Glenn F. Cota, Paul T. Buckley Nov 1997

Vertical Profiles Of Bromoform In Snow, Sea Ice, And Seawater In The Canadian Arctic, William T. Sturges, Glenn F. Cota, Paul T. Buckley

CCPO Publications

Bromoform (CHBr3) was measured in vertical profiles from the snow surface through the snowpack, sea ice, and water column to the seafloor at Resolute Bay, Canada, in the sprig of 1992. Elevated concentrations of bromoform were observed in both the ice (32-266 ng L-1 by liquid water volume) and seawater (~ 20 ng L-1 ) at the ice-water interface, associated with bromoform emission from ice microalgae. A surprising finding was a second horizon of high bromoform concentrations (336-367 ng L-1) in sea ice at the snow-ice interface. Chlorophyll and salinity were also elevated in …


Circulation, Vol. 5, No. 1, Center For Coastal Physical Oceanography, Old Dominion University Oct 1997

Circulation, Vol. 5, No. 1, Center For Coastal Physical Oceanography, Old Dominion University

CCPO Circulation

Fall 1997 issue of CCPO Circulation featuring article "CCPO, ODU, and Internet2"


Building Multi-Discipline, Multi-Format Digital Libraries Using Clusters And Buckets, Michael L. Nelson Aug 1997

Building Multi-Discipline, Multi-Format Digital Libraries Using Clusters And Buckets, Michael L. Nelson

Computer Science Theses & Dissertations

Our objective was to study the feasibility of extending the Dienst protocol to enable a multi-discipline, multi-format digital library. We implemented two new technologies: cluster functionality and publishing buckets. We have designed a possible implementation of clusters and buckets, and have prototyped some aspects of the resultant digital library.

Currently, digital libraries are segregated by the disciplines they serve ( computer science, aeronautics, etc.), and by the format of their holdings (reports, software, datasets, etc.). NCSTRL+ is a multi-discipline, multi-format digital library (DL) prototype created to explore the feasibility of the design and implementation issues involved with created a …


Simulations Of The Atlantic Ocean With A Free Surface Sigma Coordinate Ocean Model, Tal Ezer, George L. Mellor Jul 1997

Simulations Of The Atlantic Ocean With A Free Surface Sigma Coordinate Ocean Model, Tal Ezer, George L. Mellor

CCPO Publications

A sigma coordinate, free surface numerical model with turbulence dynamics has been implemented for the Atlantic Ocean and the Greenland Sea, from 80°S to 80°N. It is driven at the surface by monthly mean sea surface temperature and wind stress climatologies and is executed for 30 years. This is the first time that a model of this type, previously used mostly for coastal and regional simulations, has been implemented for the entire Atlantic Ocean and run for a long period of time. The model horizontal circulation, thermohaline overturning circulation, and meridional heat fluxes are described; the results are compared with …


Circulation, Vol. 4, No. 4, Center For Coastal Physical Oceanography, Old Dominion University Jul 1997

Circulation, Vol. 4, No. 4, Center For Coastal Physical Oceanography, Old Dominion University

CCPO Circulation

Summer 1997 issue of CCPO Circulation featuring article "HF Radar: Is It Ready for Prime Time"


Resuspension And Transport Of Fine Sediments By Waves, Chiang C. Mei, She-Jun Fan, Kang-Ren Jin Jul 1997

Resuspension And Transport Of Fine Sediments By Waves, Chiang C. Mei, She-Jun Fan, Kang-Ren Jin

OES Faculty Publications

Although waves are the primary cause of sediment resuspension in the nearshore zone, in existing theoretical models, long-scale currents induced by the mean wind are often taken to be the only agent for the diffusion and convection of resuspended sediments. We present here theoretical examples where waves play a direct role in all aspects of sediment transport. Details are given for the simple case where only waves are present; the wave-induced current and diffusivity are shown to be no less important than similar factors in the wind-driven current. Hence, in a comprehensive model, one should include not only the current …


The Detoxification Of Petroleum Contaminated Coastal Plain Sandy Soil Using An Amended Vermicomposting Approach, John Charles Kraemer Jul 1997

The Detoxification Of Petroleum Contaminated Coastal Plain Sandy Soil Using An Amended Vermicomposting Approach, John Charles Kraemer

Health Services Research Dissertations

This study explores the feasibility of utilizing an amended vermicomposting treatment approach for detoxifying petroleum hydrocarbon contaminated sandy soil. The bench-scale testing of gasoline and diesel contaminated soil using three test soil vessels and one control soil vessel was performed in a laboratory setting for a six week time period. The control soil received no treatment other than distilled water to maintain soil moisture. Treatment 1 consisted of direct application of liquid municipal biologic sludge on a weekly basis. Treatment 2 consisted of the addition of 30 Eisenia foetida earthworms and distilled water. Treatment 3 consisted of direct application of …


Core Scattering Of Stark Wave Packets, M. L. Naudeau, C. I. Sukenik, P. H. Bucksbaum Jul 1997

Core Scattering Of Stark Wave Packets, M. L. Naudeau, C. I. Sukenik, P. H. Bucksbaum

Physics Faculty Publications

We investigate the wave packet dynamics of electrons bound in the nonseparable potential of cesium in a static electric field using time-domain Ramsey interferometry. Specially shaped wave packets with low radial dispersion enable us to view the interaction between the wave packet and the atomic core. Experiments in cesium, together with quantum defect calculations of cesium and hydrogen, demonstrate changes in the motion and shape of these wave packets due to core scattering.


Speciation Of Selenium In Serum, Alice Tsapayi-Musapatike Jul 1997

Speciation Of Selenium In Serum, Alice Tsapayi-Musapatike

Chemistry & Biochemistry Theses & Dissertations

We investigated the separation of selenoprotein P and extracellular (serum) glutathione peroxidase using a concanavalin A affinity column. We were able to show that the method does not adequately separate serum glutathione peroxidase from selenoprotein P because human glutathione peroxidase binds strongly to the column. We also found that albumin can interfere with measurement serum of glutathione peroxidase activity when hydrogen peroxide is used as the substrate. When t-butyl hydroperoxide was used as the substrate, less than 10% of the measured activity was due to the presence of albumin. We also found that the pH of the elution buffer plays …


Systematics Of The Freshwater Amphipod Genus Crangonyx (Crangonyctidae) In North America, Jun Zhang Jul 1997

Systematics Of The Freshwater Amphipod Genus Crangonyx (Crangonyctidae) In North America, Jun Zhang

Biological Sciences Theses & Dissertations

The systematics of the amphipod genus Crangonyx of North America (north of Mexico) is revised, based on available collections (ca. 2240) and literature dealing with the genus. A grand total of 42 North America species of Crangonyx are recognized in the present study, 24 of them new to science. All species are described or redescribed and figured, utilizing external morphological features. Keys to both species groups and individual species are given. Phylogenetic trees are built using computer programs (PAUP, Hennig86, MacClade) based on 26 characters. Wagner parsimony produced 18 parsimonious trees and Fitch parsimony produced 45 trees. The consensus tree …


High-Order Finite-Difference Schemes And Their Application To Computational Acoustics, Joe Leo Manthey Jul 1997

High-Order Finite-Difference Schemes And Their Application To Computational Acoustics, Joe Leo Manthey

Mathematics & Statistics Theses & Dissertations

The primary focus of this study is upon the numerical stability of high-order finite-difference schemes and their application to duct acoustics. Since acoustic waves are known to be non-dissipative and non-dispersive, high-order schemes are favored for their low dissipation and low dispersion relative to the low-order schemes. The primary obstacle to the the development of explicit high-order finite-difference schemes is the construction of boundary closures which simultaneously maintain the formal order of accuracy and the numerical stability of the overall scheme. In this thesis a hybrid seven-point, fourth-order stencil for computing spatial derivatives is presented and the time stability is …


Mark-Recapture Creel Survey And Survival Models, Shampa Saha Jul 1997

Mark-Recapture Creel Survey And Survival Models, Shampa Saha

Mathematics & Statistics Theses & Dissertations

In this dissertation, we consider a model based approach to the estimation of exploitation rate of a fish population by combining mark-recapture procedures with a creel survey. We also consider the analysis of a proportional hazards survival model for randomly censored observations, known as the Koziol-Green model. The model assumes that the lifetime survivor function is a power of the censored time survivor function.

In Chapter 2, we introduce the model based approach to the estimation of the exploitation rate of a fish population by combining mark-recapture procedures with a creel survey. We assume that in the beginning of a …


The Use Of Operator Regularization In The Computation Of Effective Field Theories, Jeffrey M. Hersh Jul 1997

The Use Of Operator Regularization In The Computation Of Effective Field Theories, Jeffrey M. Hersh

Physics Theses & Dissertations

Current methods of computing low-energy effective field theories while being accurate are extremely cumbersome co implement. Operator regularization provides a way to calculate any desired effective field theory avoiding the tediousness of previous methods. This technique is shown to be an effective method in explicitly calculating the 1/mheavy corrections that match an original full theory to its low-energy effective counterpart. This is demonstrated up to two loop order for the case of a charged two field θ{4}{4} theory as well as up to one loop order for the Higgs sector of the Minimal Supersymmetric Model. Additionally, the renormalization …


The Study Of Wave-Blocking And Current Effects On Nonlinear Interactions Of Shallow-Water Waves Using Advanced Boussinesq Models, Qin Chen Jul 1997

The Study Of Wave-Blocking And Current Effects On Nonlinear Interactions Of Shallow-Water Waves Using Advanced Boussinesq Models, Qin Chen

Civil & Environmental Engineering Theses & Dissertations

The first part of this work focuses on the derivation of enhanced Boussinesq-type equations for the combined motion of waves and currents in shallow water areas.

The strategy proposed in this work is to couple two known methods which are the sponge layer concept suitable for short waves and Sommerfeld radiation condition for currents. This coupling method provides satisfactory non-reflective boundaries for the simulation of fully coupled wave/current motion as demonstrated by the numerical experiments. We verify the model against the well known solutions based on the existing theories and good agreement has been observed. The numerical results confirm the …


A Synthesized Methodology For Eliciting Expert Judgment For Addressing Uncertainty In Decision Analysis, Richard W. Monroe Jul 1997

A Synthesized Methodology For Eliciting Expert Judgment For Addressing Uncertainty In Decision Analysis, Richard W. Monroe

Engineering Management & Systems Engineering Theses & Dissertations

This dissertation describes the development, refinement, and demonstration of an expert judgment elicitation methodology. The methodology has been developed by synthesizing the literature across several social science and scientific fields. The foremost consideration in the methodology development has been to incorporate elements that are based on reasonable expectations for the human capabilities of the user, the expert in this case.

Many methodologies exist for eliciting assessments for uncertain events. These are frequently elicited in probability form. This methodology differs by incorporating a qualitative element as a beginning step for the elicitation process. The qualitative assessment is a more reasonable way …


Reverse Engineering Of Aircraft Wing Data Using A Partial Differential Equation Surface Model, Jacalyn M. Huband Jul 1997

Reverse Engineering Of Aircraft Wing Data Using A Partial Differential Equation Surface Model, Jacalyn M. Huband

Mathematics & Statistics Theses & Dissertations

Reverse engineering is a multi-step process used in industry to determine a production representation of an existing physical object. This representation is in the form of mathematical equations that are compatible with computer-aided design and computer-aided manufacturing (CAD/CAM) equipment. The four basic steps to the reverse engineering process are data acquisition, data separation, surface or curve fitting, and CAD/CAM production. The surface fitting step determines the design representation of the object, and thus is critical to the success or failure of the reverse engineering process. Although surface fitting methods described in the literature are used to model a variety of …


Evaluation Of Solid Phase Extraction Followed By Supercritical Fluid Elution Of Semi-Volatile Organic Compounds In Toxicity Characteristic Leachates, William Edward Corl Iii Jul 1997

Evaluation Of Solid Phase Extraction Followed By Supercritical Fluid Elution Of Semi-Volatile Organic Compounds In Toxicity Characteristic Leachates, William Edward Corl Iii

Chemistry & Biochemistry Theses & Dissertations

The Environmental Protection Agency (EPA) developed the toxicity characteristic leaching procedure (TCLP) to determine the potential for unknown wastes to leach haz.ardous constituents into the environment. Methods currently being used for the extraction of semi-volatile organic compounds from aqueous TCLP leachates involve acid/base partitioning into methylene chloride. The concentrated extract is then analyzed by gas chromatography/mass spectrometry (GC/MS). The methods are either timeconsuming or labor intensive and they generate significant volumes of haz.ardous wastes themselves. Considering the haz.ards and disposal costs of methylene chloride wastes, great interest has been elicited by the EPA in other extraction techniques which would reduce …


Fabrication And Evaluation Of Boron-Doped Cvd Diamond Microelectrodes, Song Pang Jul 1997

Fabrication And Evaluation Of Boron-Doped Cvd Diamond Microelectrodes, Song Pang

Chemistry & Biochemistry Theses & Dissertations

The electrochemical behavior of boron-doped diamond microelectrodes has been studied in acetonitrile solutions containing two redox couples using cyclic voltammetry. One test system is 1-2.5 mM ferrocene, containing 0.1 M Tetrabutyl ammonium hexafluorophosphate (TBAH). This well-known reversible redox system involves only one electron transfer with little or no change in the solvation sphere and no breakage/formation of chemical bonds. Another test system is a 1 mM S2Mo180644- solution containing 0.1 M HCIO4. This is one of the most complicated redox systems. In the presence of acid, electrons are usually transferred consecutively and …


Stomach Content Analysis Of Stranded Bottlenose Dolphins, Tursiops Truncatus, In Virginia, 1987-1996, John Mcgurk Jul 1997

Stomach Content Analysis Of Stranded Bottlenose Dolphins, Tursiops Truncatus, In Virginia, 1987-1996, John Mcgurk

Biological Sciences Theses & Dissertations

I examined the stomach contents from 94 bottlenose dolphins, Tursiops truncatus, that were stranded along the Virginia coastline from 1987 through 1996. Samples from 1987 through 1991 were obtained from the National Museum of Natural History (NMNH) and samples from 1992 through 1996 were collected by the Virginia Marine Science Museum (VMSM) Stranding Team. Prey species were identified using fish otoliths and cephalopod beaks.

The dolphins examined fed on 23 species of fish and one genus of cephalopods. The primary prey species was Atlantic croaker (Micropogonias undulatus); secondary species were weakfish (Cynoscion regalia), spot (Leiostomus xanthurus), silver perch (Bairdiella chrysoura), …


Single Row Routing: Theoretical And Experimental Performance Evaluation, And New Heuristic Development, David A. Hysom May 1997

Single Row Routing: Theoretical And Experimental Performance Evaluation, And New Heuristic Development, David A. Hysom

Computer Science Theses & Dissertations

The Single Row Routing Problem (SRRP) is an abstraction arising from real-world multilayer routing concerns. While NP-Complete, development of efficient SRRP routing heuristics are of vital concern to VLSI design. Previously, researchers have introduced various heuristics for SRRP; however, a comprehensive examination of SRRP behavior has been lacking.

We are particularly concerned with the street-congestion minimization constraint, which is agreed to be the constraint of greatest interest to industry. Several theorems stating lower bounds on street congestion are known. We show that these bounds are not tight in general, and argue they may be in error by at least 50% …


Circulation, Vol. 4, No. 3, Center For Coastal Physical Oceanography, Old Dominion University Apr 1997

Circulation, Vol. 4, No. 3, Center For Coastal Physical Oceanography, Old Dominion University

CCPO Circulation

Spring 1997 issue of CCPO Circulation featuring article "Fostering Oceanographic Collaboration in Cameroon"


Councilmanic Perceptions Of Water Policy For The Lake Gaston Water Supply Project In Virginia And North Carolina, Beverly Mcafee Hedberg Apr 1997

Councilmanic Perceptions Of Water Policy For The Lake Gaston Water Supply Project In Virginia And North Carolina, Beverly Mcafee Hedberg

Theses and Dissertations in Urban Services - Urban Management

The purpose of this case study is to analyze the perceptions of city council members in formulating and implementing policy on the Lake Gaston Water Supply Project in Virginia and North Carolina. A comparison of the perceptions of twenty-three members of three city councils: Henderson, North Carolina; Roanoke Rapids, North Carolina; and Virginia Beach, Virginia serves as the basis for analysis. Their perceptions of the issues and how they view other actors in the intergovernmental arena, within the context of the Lake Gaston Water Supply Project.

Specifically, the research examines how city council members view (1) water-policy issues, (2) the …


Ecology Of The Early Life History Of The Caribbean Spiny Lobster, Panulirus Argus: Recruitment, Predation, And Habitat Requirements, Charles A. Acosta Apr 1997

Ecology Of The Early Life History Of The Caribbean Spiny Lobster, Panulirus Argus: Recruitment, Predation, And Habitat Requirements, Charles A. Acosta

Biological Sciences Theses & Dissertations

Recruitment variability of the early life history stages of marine benthic organisms can have profound consequences on population dynamics. I studied factors affecting recruitment success of postlarvae and early juveniles of the Caribbean spiny lobster. I examined patterns in postlarval supply, investigated wind forcing as a potential transport mechanism for recruiting postlarvae, and quantified predation on postlarvae in south Florida, USA. In an eight-year time series, spiny lobster postlarval supply occurred year-round between the new and first quarter lunar phases. The major annual peak occurred around March corresponding to spawning activity ten months earlier, and a smaller non-seasonal peak occurred …


Microzooplankton Dynamics In Lower Chesapeake Bay And Its Major Tributaries, Gyung Soo Park Apr 1997

Microzooplankton Dynamics In Lower Chesapeake Bay And Its Major Tributaries, Gyung Soo Park

Biological Sciences Theses & Dissertations

This study identified the temporal and spatial variability of microzooplankton density and biomass at 14 stations located within Chesapeake Bay and four rivers. Microzooplankton are defined as those heterotrophic organisms which range from 20 to 200 $\mu$m in size, and in this study were mainly composed of copepod nauplii, rotifers, and ciliates. Ciliates were the most abundant microzooplankton, comprising more than 90% of the total density, with copepod nauplii representing approximately 50% of the total microzooplankton biomass (carbon content). Rotifers contributed less than 5% for both density and biomass of the total microzooplankton.

Maximum ciliate abundance occurred from spring to …


Three-Dimensional Aerodynamic Design Optimization Using Discrete Sensitivity Analysis And Parallel Computing, Amidu Olawale Oloso Apr 1997

Three-Dimensional Aerodynamic Design Optimization Using Discrete Sensitivity Analysis And Parallel Computing, Amidu Olawale Oloso

Mechanical & Aerospace Engineering Theses & Dissertations

A hybrid automatic differentiation/incremental iterative method was implemented in the general purpose advanced computational fluid dynamics code (CFL3D Version 4.1) to yield a new code (CFL3D.ADII) that is capable of computing consistently discrete first order sensitivity derivatives for complex geometries. With the exception of unsteady problems, the new code retains all the useful features and capabilities of the original CFL3D flow analysis code. The superiority of the new code over a carefully applied method of finite-differences is demonstrated.

A coarse grain, scalable, distributed-memory, parallel version of CFL3D.ADII was developed based on "derivative stripmining". In this data-parallel approach, an identical copy …


Designing A High-Quality Network: An Application-Oriented Approach, Sudheer Dharanikota Apr 1997

Designing A High-Quality Network: An Application-Oriented Approach, Sudheer Dharanikota

Computer Science Theses & Dissertations

As new computer network technologies emerge, the application designers and the application users expect an increasing level of quality of service from them. Hence, it is a common practice in the newer technologies to provide more Quality of Service (QoS) components. Until now, these QoS solutions have been both network-technology specific and network-oriented solutions. In this thesis, we present an application-oriented approach to design a high quality network which is independent of the underlying communication technology. In this thesis, we propose a QoS architecture to "provide predictable performance to the end-to-end application users in a high quality networking environment." In …


Ice Transport In The Queen Elizabeth Islands, Canadian Arctic Using Detrital Fe Oxide Grain Composition, Duan Li Apr 1997

Ice Transport In The Queen Elizabeth Islands, Canadian Arctic Using Detrital Fe Oxide Grain Composition, Duan Li

OES Theses and Dissertations

Nine Fe oxide mineral types (45pm-250pm) separated from 54 glacial and glaciomarine sediment samples from the Queen Elizabeth Islands (QEI) of Canada were analyzed for 12 elements by electron microprobe to determine the dispersal patterns of ice rafted debris in this area. Both cluster analysis and discriminant function analysis (DFA) on the chemical compositions were used to match each detrital Fe oxide grain to a source The entire QEI area can be subdivided into eight unique areas based on the elemental composition of the Fe oxide minerals. These subdivisions are similar to the source areas based on the assemblage of …