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Air Pollution Transport Modeling, David M. Paal Dec 1993

Air Pollution Transport Modeling, David M. Paal

Theses and Dissertations

This research effort addresses modeling of the transportation of air pollution in the atmosphere and the numerical analysis of the partial differential equations used in such modeling. Three Gaussian models are examined and compared using example problems. Several finite difference schemes are developed to solve the partial differential equations used in air pollution transport modeling. This study examines three Gaussian models SCREEN, AFTOX, and the program GAUSPLUM. The model GAUSPLUM is developed in this study and uses the Ada programming language and the analytic solution to the advection- diffusion equation. Numerical analysis of the partial differential equations PDE used in …


Performance Impacts For Actuator Misalignments And Failures In Large- Aperture Adaptive-Optic Telescopes, Timothy D. Hogan Dec 1993

Performance Impacts For Actuator Misalignments And Failures In Large- Aperture Adaptive-Optic Telescopes, Timothy D. Hogan

Theses and Dissertations

Large-aperture telescopes require adaptive optics in order to compensate for atmospheric turbulence which would otherwise negate the resolution advantages of using large apertures. This investigation analyzes the impacts of misalignments and failures, in the deformable mirror actuators, upon the performance of such systems. A numerical simulation of a standard adaptive optics system is used to generate characteristic optical transfer function OTF and signal-to-noise ratio SNR performance metrics. The performance impacts of the misalignments are shown to be dependent upon the Fried parameter effective telescope diameter, the source object brightness, and the control system time delay. The degree of performance degradation …


Developing Prediction Regions For A Time Series Model For Hurricane Forecasting, William Cheman Dec 1993

Developing Prediction Regions For A Time Series Model For Hurricane Forecasting, William Cheman

Theses and Dissertations

In this thesis, a class of time series models for forecasting a hurricanes future position based on its previous positions and a generalized model of hurricane motion are examined and extended. Results of a literature review suggest that meteorological models continue to increase in complexity while few statistical approaches, such as linear regression, have been successfully applied. An exception is provided by a certain class of time series models that appear to forecast storms almost as well as current meteorological models without their tremendous complexity. A suggestion for enhancing the performance of these time series models is pursued through an …


Shock Wave Interaction With L-Shaped Structures, Richard C. Miller Dec 1993

Shock Wave Interaction With L-Shaped Structures, Richard C. Miller

Theses and Dissertations

This study investigated the interaction of shock waves with L-shaped structures using the CTH hydrodynamics code developed by Sandia National Laboratories. Computer models of shock waves traveling through air were developed using techniques similar to shock tube experiments. Models of L-shaped buildings were used to determine overpressures achieved by the reflecting shock versus angle of incidence of the shock front. An L-shaped building model rotated 45 degrees to the planar shock front produced the highest reflected overpressure of 9.73 atmospheres in the corner joining the two wings, a value 9.5 times the incident overpressure of 1.02 atmospheres. The same L-shaped …


Identification And Quantitation Of Volatile Amines In Chesapeake Bay Sediments, Neeraja Y. Krishna Oct 1993

Identification And Quantitation Of Volatile Amines In Chesapeake Bay Sediments, Neeraja Y. Krishna

Chemistry & Biochemistry Theses & Dissertations

Sediments from different parts of the Chesapeake Bay were analyzed to determine the presence of volatile amines. A HF-HCl extraction method was used to extract both exchangeable and fixed amines from the sediments and a purge-and-trap technique was used to concentrate the amines. Following derivatization with heptafluorobutyric anhydride (HFBA), the HFBA-amines were analyzed by gas chromatography with electron capture detection and with mass spectrometric detection. One primary amine, i-amylamine with a concentration ranging from 0. 78 nmoles/g dry weight to < 0.05 nmoles/g dry weight was found in a total of twenty seven samples collected on three different dates in 1993. Another primary amine, 2-methylbutylamine with a concentration ranging from 0.18 nmoles/g dry weight to < 0.05 nmoles/g dry weight was found in a total of twenty three samples collected on three different dates in 1993. A secondary amine, diethylamine was detected but could not be quantified in a total of seven samples collected in September 1993. The concentrations of these amines varied with location in the Bay, depth in the sediment, and time of year the sediments were collected. The origin of i-amylamine and 2-methylbutylamine might be from the biological decarboxylation of amino acids leucine and isoleucine, respectively. The origin of diethylamine is unknown.


Description, Distribution, And Abundance Of The Blue Crab, Callinectes Sapidus (Rathbun), Spawning Stock Of The Lower Chesapeake Bay, Patrick John Geer Oct 1993

Description, Distribution, And Abundance Of The Blue Crab, Callinectes Sapidus (Rathbun), Spawning Stock Of The Lower Chesapeake Bay, Patrick John Geer

OES Theses and Dissertations

The lower Chesapeake Bay spawning stock of the blue crab, Callinectes sapidus, (Rathbun), is examined for seven years (1986 - 1992) in an attempt to better understand stock behavior. Three methods of post-stratification are used to describe the distribution and movement of the population over time. The three methods, density strata, geographic zones, and depth strata, did well in explaining movements of the population, indicating a trend of increased concentration of blue crabs near the eastern Bay late in the spawning season - October. The data suggest a bimodal period of spawning and a trimodal period of abundance. The …


The Biogeochemistry Of Iodine In Seawater, Lingsu Zhang Jul 1993

The Biogeochemistry Of Iodine In Seawater, Lingsu Zhang

OES Theses and Dissertations

Iodate and iodide are the two major species of iodine in seawater. In comparison to iodate, iodide is thermodynamically unstable in oxic seawater. The conversion (or reduction) of iodate to iodide may be mediated via biological activities. Since biological activities vary with the season, the conversion of iodate to iodide may also vary seasonally. The conversion (or oxidation) of iodide to iodate is thermodynamically feasible, but the mechanism is poorly known. Hydrogen peroxide, which is ubiquitous in surface seawater, may oxidize iodide to iodate.

Water samples were collected in the middle and lower Chesapeake Bay in different seasons between 1990 …


Production And Decomposition Of Hydrogen Peroxide By Marine Phytoplankton, Dong-Beom Kim Jul 1993

Production And Decomposition Of Hydrogen Peroxide By Marine Phytoplankton, Dong-Beom Kim

OES Theses and Dissertations

H202 in seawater has complicated sources and sinks. The relative importance of biological regulation of H202 compared to other processes is not well understood. In addition, environmental factors affecting the biological regulation of H202 are largely unknown. Marine phytoplankton was examined for the kinetics of the production and decomposition of H202 in the dark. Effects of varying environmental factors such as light, temperature, salinity, nutrients, amino acids, trace metals and growth phase, were examined. H202 was determined with the scopoletin-fluorescence decay method.

Five out of 11 species produced …


Modeling Nutrient And Plankton Processes In The California Coastal Transition Zone, John Roland Moisan Apr 1993

Modeling Nutrient And Plankton Processes In The California Coastal Transition Zone, John Roland Moisan

OES Theses and Dissertations

Two time- and space-dependent, physical-bio-optical models have been developed for the California Coastal Transition Zone (CTZ) region with the overall objective of understanding and quantifying the processes th at contribute to the spatial and temporal development of nutrient and plankton distributions in the CTZ. The first of these models considers only time- and vertical processes at specific locations in the CTZ. The model food web components include: silicate, nitrate, ammonium, two phytoplankton size fractions, copepods, doliolids, euphausiids and a detritus pool. The wavelength dependent attenuation of the subsurface irradiance field, due to sea water, phytoplankton pigment concentrations and dissolved organic …


The Biogeochemistry Of Hydrogen Sulfide In The Open Ocean, Joël Radford-Knoery Apr 1993

The Biogeochemistry Of Hydrogen Sulfide In The Open Ocean, Joël Radford-Knoery

OES Theses and Dissertations

Hydrogen sulfide is a poorly quantified component of the global sulfur cycle. In seawater, its dissolved species (dissolved sulfide) can react with trace metals to form dissolved complexes and insoluble compounds. Therefore, the study of dissolved° sulfide in the open ocean can yield a better understanding of the biogeochemical cycles of sulfur and trace metals.

The biogeochemical cycling of dissolved sulfide was examined using specially developed sampling and analytical methods. In the western North Atlantic and central Equatorial Pacific Oceans, total dissolved sulfide concentrations ranged from /L; they were highest, in the mixed layer and decreased with depth. The depth …


Paleobathymetric Interpretation Of Pleistocene Sediments In The South Padre Island Area, Northwestern Gulf Of Mexico, Using Benthic Foraminiferal Morphology, Karen Ianthe Kruebbe-Belwood Apr 1993

Paleobathymetric Interpretation Of Pleistocene Sediments In The South Padre Island Area, Northwestern Gulf Of Mexico, Using Benthic Foraminiferal Morphology, Karen Ianthe Kruebbe-Belwood

OES Theses and Dissertations

This study tested the validity of using intraspecific variation in benthic foraminifera as a means for determining Pleistocene paleobathymetry. Canonical variate analysis was used as a means for determining visually undetectable but statistically significant differences in the morphology of selected species. Two species, Cassidulina subglobosa and Uvigerina peregrina, were collected from Pleistocene well cuttings from the northwest Gulf of Mexico. The canonical analysis involved comparing the intraspecific variation of these Pleistocene species to their counterparts occurring in the modern Gulf of Mexico, where intraspecific variation was previously analyzed and found to be sufficient to allow detection of bathymetric differences …


Applications Of Gaming Techniques To Coastal Zone Problems, Robert Adam Drews Feb 1993

Applications Of Gaming Techniques To Coastal Zone Problems, Robert Adam Drews

Theses and Major Papers

The boundary between sea and land is an area which presents enormous management challenges. It is an area of fragile ecology, dense and growing population, multiple competing demands for resource use, a multitude of regulatory agencies, and far from complete scientific understanding. Given these difficulties, planning for coastal zone management frequently suffers from incomplete data, lack of consensus among users, and lack of support from government authorities. This paper proposes gaming as a tool for assisting in the information gathering, education, consensus building, and communications elements of planning. This is achieved by developing a planning game which is designed to …


The Kuril Islands Dispute: An Obstacle In Russo-Japanese Relations, Roderick J. Fraser Jr. Jan 1993

The Kuril Islands Dispute: An Obstacle In Russo-Japanese Relations, Roderick J. Fraser Jr.

Theses and Major Papers

The controversy between Japan and Russia over the ownership of the Kuril Islands is a significant barrier to improved diplomatic relations in the Far Eastern region. Because of this dispute, Japan and Russia have not yet signed a peace treaty to formally end the second world war and neither side seems willing to make any significant concessions to reach a compromise. The issue of ownership of these islands has been a continuing focal point of Russo-Japanese relations since the two nations first made contact in the late eighteenth century. The various aspects of this dispute are complex and have continued …


The Role Played By Semisubmersible Exploratory Drilling Platforms As A Vector In Marine Biological Introductions, Sean S. Bercaw Jan 1993

The Role Played By Semisubmersible Exploratory Drilling Platforms As A Vector In Marine Biological Introductions, Sean S. Bercaw

Theses and Major Papers

Through discussion of Semisubmersible Exploratory Drilling Platforms and their role as vectors in marine biological introductions, this paper establishes a base of knowledge for future referral. Included in this project are details of semisubmersibles, their unique characteristics and operations, historical movements, past introductions, future operations, and continuing potential for invasions. The significance of semisubmersibles as biological vectors is further addressed. Three criteria will be used to assess the significance of the role of semisubmersibles in the introduction of alien species: first, what is the rate of SEDP movements over time; second, how are SEDP movements unique, and what role does …


Implications Of Soviet And Russian Nuclear Waste Dumping In The Arctic Marine Environment, Jeffrey L. Canfield Jan 1993

Implications Of Soviet And Russian Nuclear Waste Dumping In The Arctic Marine Environment, Jeffrey L. Canfield

Theses and Major Papers

This study examines fragmentary information on ocean dumping of radioactive wastes conducted by the Soviet Union and the Russian Federation from 1959 to the present, then assays the impact of this activity in terms of the legal historical, oceanographic and political contexts. Lacking accurate and thorough data on many aspects of the activity, it has been necessary to infer and extrapolate from what is know about the impact of radioactive materials on analogous ocean sites and regimes where radionuclides have been introduced and monitored by other states. Preliminary assessments are provided for the impact on human uses of resources in …


Nonpoint Source Pollution From Agricultural Runoff: An Analysis Of Problems, Solutions, And The Remedial Action Plan Process For The St. Louis River Basin, Thomas V. Giddings Jan 1993

Nonpoint Source Pollution From Agricultural Runoff: An Analysis Of Problems, Solutions, And The Remedial Action Plan Process For The St. Louis River Basin, Thomas V. Giddings

Theses and Major Papers

Agricultural nonpoint source pollution is the pollution coming from agricultural production, which has no clear origin. It comes from a diffuse source, such as a farm field or an animal holding area. While programs and studies probe every facet of point sources and extol the efforts of point source clean-up, the relatively more difficult task of identifying nonpoint sources and the process of proposing to do something about them has been largely ignored. Reducing the adverse impacts on the environment from farm related activities requires knowledge of the various pollutants and how pollutant pathways can be interrupted. Nutrients, and pesticides …


The Dilemma Of Dredging And Dredged Material Disposal In The Aquatic Waters Of Rhode Island And Its Impact On The Regional Marina Industry, Darryl J. Keith Jan 1993

The Dilemma Of Dredging And Dredged Material Disposal In The Aquatic Waters Of Rhode Island And Its Impact On The Regional Marina Industry, Darryl J. Keith

Theses and Major Papers

Since the closures, in 1971, of the Prudence Island and Brenton Reef disposal sites, water-related industries have not had aquatic disposal of dredged sediments as a management option. The marina industry in Rhode Island has been especially impacted as natural sedimentation processes have reduced the water depths at many of these locations and have resulted in the loss of business as operators have been unable to operate their marinas to their fullest potential. The elimination of this option is based on political and environmental concerns over declines in local commercial fisheries which are alleged to be the result of the …


Towards A Regional Coastal Zone Management Program In The Oecs, Keith E. Nichols Jan 1993

Towards A Regional Coastal Zone Management Program In The Oecs, Keith E. Nichols

Theses and Major Papers

The Islands of the Lesser Antilles are described as "truly archipelagic, enjoying the characteristic features of both oceanic and coastal islands." Once considered pristine and far removed from the influences of pollution from coastal areas, they are now faced with the realities of their own solid waste problems, resource degradation and over-exploitation, as well as human health impacts from contaminated rivers and coastal areas. Each of these territories can be considered packages of economic, political and cultural networks, attempting to provide for individual and nationwide needs while seeking economic growth and self-sufficiency. If developed properly and used in tandem with …


Five Marine Resource Management Programs: Innovations And Common Themes, Louisa Rand Moore Jan 1993

Five Marine Resource Management Programs: Innovations And Common Themes, Louisa Rand Moore

Theses and Major Papers

This paper investigates essential elements of marine resource management programs, particularly how they are initiated and what is needed for their success. The focus of this paper is on management planning for sites where marine resources are still largely intact as opposed to those which are severely disturbed. Planning is aimed at determining carrying capacity of the marine systems and limiting disturbances accordingly. Question for this inquiry were developed from research of a bay in eastern Maine where marine resources have not been severely disturbed, but are vulnerable to over-exploitation due to lack of coordinated management. Using these questions, five …


Conflicts In Use: The Impacts Of The Oil And Gas Industry On The Herring Fishery In The North Sea, Cornelia Ann Pasche Jan 1993

Conflicts In Use: The Impacts Of The Oil And Gas Industry On The Herring Fishery In The North Sea, Cornelia Ann Pasche

Theses and Major Papers

The interaction of the herring (Clupea harengus) with the oil and gas industry in the North Sea is reviewed. The population crash of the herring in the early 1970's and the subsequent closing of that important fishery between 1977 and 1983 has drawn considerable attention to the influences, both biotic and abiotic, affecting the recruitment to the North Sea stock. Current accepted theory points to a change in oceanic current and the subsequent decrease in salinity in the North Sea region, resulting in a change in plankton availability for larval herring as the cause of the recruitment failure during the …


Linking Management And Markets: The Northwest Atlantic Sea Herring Industry And The Case For "Regional" Quotas, Peter Jessup Moore Jan 1993

Linking Management And Markets: The Northwest Atlantic Sea Herring Industry And The Case For "Regional" Quotas, Peter Jessup Moore

Theses and Major Papers

This review and characterization of the U.S. Atlantic sea herring fishery and industry analyzes opportunities for and constraints to developing the herring resource more fully. Chapter 1 describes the herring resource, the existing fishery, and reviews current research into the international transboundary migrations of the Atlantic sea herring. Chapters 2 and 3 describe the development of the herring fishery management plan in the context of the global herring market and the management complications that arise from the transboundary migrations of the stocks. Examples of successful linkages between fisheries management and market development are described in Chapter 4 to illustrate the …


Marine Safety And Pollution Prevention: The Role Of The Port State, Jonathan Douglas Sarubbi Jan 1993

Marine Safety And Pollution Prevention: The Role Of The Port State, Jonathan Douglas Sarubbi

Theses and Major Papers

This paper will examine the evolving role of the port State with regard to the enforcement of international safety of life at sea and pollution control standards and its effect on improving maritime safety and reducing vessel-source pollution. Chapter 2 will analyze the flag State enforcement regime, with particular emphasis on flags of convenience or open registries countries demonstrating the inadequacy of flag State enforcement and the need for port State control. Chapter 3 will examine the concept and legal requirements of the port State control regime. Chapter 4 will focus on the role of the port State with respect …


The Rise And Fall Of New Bedford Whaling, As Documented By The Whalemen's Shipping List And Merchants' Transcript, Michael J. Tighe Jan 1993

The Rise And Fall Of New Bedford Whaling, As Documented By The Whalemen's Shipping List And Merchants' Transcript, Michael J. Tighe

Theses and Major Papers

The purpose of this study is to document the rise and fall of the New Bedford whaling industry-which was, in effect, the American whaling industry-through the pages of the Whalemen's Shipping List and Merchants' Transcript. This analysis will proceed int he following ways. First, this study will detail the origins of the American whaling industry and it development up to the first issue of the Whalemen's Shipping List and Merchants' Transcript on March 17, 1843. Whaling developed in colonial American because many of thos first settlers previously worked in the English and Dutch whaling fleets. This section also will include …


Analysis Of Factors Contributing To Environmental Activism: A Case Study Of Beach Clean-Up Participants, Elizabeth Ann Fuller Jan 1993

Analysis Of Factors Contributing To Environmental Activism: A Case Study Of Beach Clean-Up Participants, Elizabeth Ann Fuller

Theses and Major Papers

This study was initiated to investigate factors which contribute to environmental activism. Towards this end, three hypotheses were investigated. First, it was hypothesized that beach clean-up participants would harbor pro-environmental attitudes. Second, it was hypothesized that participants would be relatively young, politically liberal, well-educated, and wealthy. Finally, it was hypothesized that particular types of social structure would influence a person's decision to participate in a beach clean-up. Specifically, it was hypothesized that participants at each clean-up location would be clique members and/or would be structurally equivalent. Surprising, it was revealed that there was virtually no difference in attitude between the …


User Perceptions Of The Environmental Quality And Governance System Of Narragansett Bay, Mary-Beth Gadzik Hart Jan 1993

User Perceptions Of The Environmental Quality And Governance System Of Narragansett Bay, Mary-Beth Gadzik Hart

Theses and Major Papers

This paper hypothesizes that there will be differences in perception between the users and managers of Narragansett Bay with respect to (1) the Bay's environmental quality; and (2) the effectiveness of the governance system established to manage and regulate the Bay. Any discrepancies in the perception of the quality of Narragansett Bay's shoreline and water resources among various user groups are likely to contribute to conflicts between users, and a less efficient approach to the management of Bay resources. Thus, the identification of where management policies may diverge from the interests of public user groups will serve to improve resource …


Study Of An Endangered Species Enhancement Program In Coastal Wetlands: Public Perceptions And Management Strategies, Virginia Marueen Witkowski Jan 1993

Study Of An Endangered Species Enhancement Program In Coastal Wetlands: Public Perceptions And Management Strategies, Virginia Marueen Witkowski

Theses and Major Papers

Understanding what motivates public perception and actions is important in assessing public response and forecasting the success of resource management plans. Failure of the policy makers to foresee public reaction can result in expensive delays, bad press and lengthy court battles which at best, increases the cost of implementation and at worst stops resource management projects altogether. An endangered species management program was stopped at the Seal Beach National Wildlife Refuge in Southern California when an animal right's organization protested the euthanizing of non-native red foxes where were decimating endangered populations of California Least terns and Clapper rails in the …


Molecular Diffusion Coefficients For Polycyclic Aromatic Hydrocarbons In Air And Water, Kurt E. Gustafson Jan 1993

Molecular Diffusion Coefficients For Polycyclic Aromatic Hydrocarbons In Air And Water, Kurt E. Gustafson

Dissertations, Theses, and Masters Projects

No abstract provided.


Market Interactions And Competition Between Public And Private Oyster Production And Supplies From Other States, Ya-Ke Hsu Jan 1993

Market Interactions And Competition Between Public And Private Oyster Production And Supplies From Other States, Ya-Ke Hsu

Dissertations, Theses, and Masters Projects

Oyster production in Virginia has declined dramatically in the past ten years, causing Virginia oyster processors to rely increasingly on oyster supplies from other regions. In response to the industry problems, the Virginia Marine Resources Commission (VMRC) developed and began implementing an Oyster Fishery Management Plan (OFMP) in 1985. Primarily, the plan seeks to increase Virginia oyster production from both public and leased grounds. A large increase in production could significantly affect the oyster market. There is thus a need to understand the Virginia oyster market, which derives raw material supplies primarily from public and leased-grounds production and from other …


Modeling Trihalomethane Formation In Bromide-Containing Surface Water Undergoing Conventional Treatment, Maureen Mcbride Smith Jan 1993

Modeling Trihalomethane Formation In Bromide-Containing Surface Water Undergoing Conventional Treatment, Maureen Mcbride Smith

Theses Digitization Project

No abstract provided.


Boundary Layer Structure In Homogeneous Tidal Flows: A Theoretical And Numerical Study, Jian Shen Jan 1993

Boundary Layer Structure In Homogeneous Tidal Flows: A Theoretical And Numerical Study, Jian Shen

Dissertations, Theses, and Masters Projects

No abstract provided.