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Phytoplankton Assemblages Associated With A Bloom Of Ptychodiscus Brevis Off The North Carolina Coast, Traycie Lea West

Biological Sciences Theses & Dissertations

A bloom of the dinoflagellate Ptychodiscus brevis occurred off the North Carolina coast in late 1987, and samples were forwarded by NOAA to the Old Dominion University Phytoplankton Laboratory for total phytoplankton analysis. Six sampling stations were chosen to represent different bloom scenarios and these six were clustered into three site groups based on the concentrations of statistically significant taxa. Abundances of phytoplankton taxonomic groups over time were examined in relation to P. brevis concentrations to identify any general tendencies. These results indicated the total phytoplankton concentration, and most taxonomic groups, increased at all three site groups regardless of the …

Study Of Single-Fiber Fiber Optic Lever Microphone, Trung Duc Nguyen

Electrical & Computer Engineering Theses & Dissertations

Fiber optic sensors are widely used in today's technological applications, providing many advantages that conventional sensors lack. In particular, there is a demand in hypersonic applications to develop microphones to measure acoustic pressure that performs in high temperature and noisy surroundings. This thesis analyzes fiber optic lever microphones (FOLM), since they perform at high temperatures. An FOLM system is an intensity modulated sensor, which is simple to implement and is small in size. Two models of the FOLM have been fabricated and calibrated. The first model uses a seven-element fiber array while the second uses a single-fiber to transmit and …

Katharine's Dream, Karen Maceira

English Theses & Dissertations

Katharine's Dream is about a girl born into a family of great passion and great fear. Not all members of the family survive this devastating combination. These poems tell of who survived and how, and of who did not.

The poems are predominantly free verse lyrics which use standard diction and syntax. More often than not, they employ a short line, dense imagery and "white space," which frames the images and ideas, in the words of Mary Oliver, with the necessary "silence." Though the rhythms of some of the poems flow among smoothly, line breaks in others often suggest the …

A Computer-Based Strategy To Facilitate Organizational Learning Process, Charles B. Keating

Engineering Management & Systems Engineering Theses & Dissertations

This research investigated the development of Organizational Learning Process (OLP) through the application of a computer-based strategy in an organizational setting. OLP is developed from the organizational learning literature as an integration of similar concepts of organizational processes of inquiry essential to organizational learning. These concepts included: organizational dialectic (Argyris and Schon 1978), surfacing and testing mental models (Senge 1990a,1990b), and interpretation process (Daft and Weick 1984). A qualitative research methodology was developed within a participatory action research framework (Whyte 1989). A six phase research project, designed as a computer-based strategy to generate OLP, was applied in an organizational setting. …

Multilevel Parallel Communications, Sanjay Khanna

Computer Science Theses & Dissertations

The research reported in this thesis investigates the use of parallelism at multiple levels to realize high-speed networks that offer advantages in throughput, cost, reliability, and flexibility over alternative approaches. This research specifically considers use of parallelism at two levels: the "upper" level and the "lower" level. At the upper level, N protocol processors perform functions included in the transport and network layers. At the lower level, M channels provide data and physical layer functions. The resulting system provides very high bandwidth to an application. A key concept of this research is the use of replicated channels to provide a …

A Multivariate Quality Control Approach For Automated Manufacturing Systems, Hisham Naim Ashur

Engineering Management & Systems Engineering Theses & Dissertations

In today's competitive manufacturing environment, effective and practical statistical quality control approaches are essential. A successful process control approach needs to provide on line real time monitoring of quality related characteristics.

No longer acceptable is an approach that analyzes quality related data only after the product is produced. A statistical process control approach that monitors the process during production and that reports trouble spots before bad products are made is necessary in an automated manufacturing environment.

An automated manufacturing environment is characterized by high volume production runs and short production cycles. Traditional statistical process control approaches are not capable of …

Attitudes Of Virginia Dental Hygienists Towards Issues Relevant To The Independent Practice Of Dental Hygiene, Linda Hawkins Mccain

Community & Environmental Health Theses & Dissertations

Adequate studies have not been conducted to assess the attitudes of dental hygienists toward independent practice of dental hygiene. The purpose of this study was to investigate these attitudes. The method of investigation was a survey questionnaire designed by the principle investigator. The research results indicated weak support for the independent practice of dental hygiene. The support for general supervision of hygienists in Virginia and the desire to be allowed to practice in nontraditional settings was stronger. There was reported a very strong opposition to preceptorship in dental hygiene. The majority of Virginia dental hygienists agreed that they were educationally …

Boundary Layer Influences On The Subsonic Near-Wake Of A Family Of Three-Dimensional Bluff Bodies, Charles Willliam Alcorn

Mechanical & Aerospace Engineering Theses & Dissertations

A study is reported on subsonic bluff body near-wake flows. It has been determined that one family of bluff bodies, namely slanted-base ogive cylinders, can experience either a closed recirculating near-wake, or a longitudinal vortex near-wake depending on the base slant-angle and the Reynolds number. This suggests a dependence of near-wake parameters on the state of the boundary layer ahead of separation. This report addresses the influence of the boundary layer on the near-wake of slanted-base bluff bodies. Experiments were conducted in two facilities, the 6-inch Magnetic Suspension and Balance System (MSBS) at NASA Langley Research Center and the Old …

A Framework For Data Sharing In Computer Supported Cooperative Environments, Mohamed Youssef Eltoweissy

Computer Science Theses & Dissertations

Concurrency control is an indispensable part of any information sharing system. Co-operative work introduces new requirements for concurrency control which cannot be met using existing applications and database management systems developed for non-cooperative environments. The emphasis of concurrency control in conventional database management systems is to keep users and their applications from inadvertently corrupting data rather than support a workgroup develop a product together. This "insular" approach is necessary because applications that access the database have been built with the assumptions that they have exclusive access to the data they manipulate and that users of these applications are generally oblivious …

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 …

Studies On Nonequilibrium Phenomena In Supersonic Chemically Reacting Flows, Rajnish Chandrasekhar

Mechanical & Aerospace Engineering Theses & Dissertations

This study deals with a systematic investigation of nonequilibrium processes in supersonic combustion. The two-dimensional, elliptic Navier-Stokes equations are used to investigate supersonic flows with nonequilibrium chemistry and thermodynamics, coupled with radiation, for hydrogen-air systems. The explicit, unsplit MacCormack finite-difference scheme is used to advance the governing equations in time, until convergence is achieved.

For a basic understanding of the flow physics, premixed flows undergoing finite rate chemical reactions are investigated. Results obtained for specific conditions indicate that the radiative interactions vary substantially, depending on reactions involving HO$\sb2$ and NO species, and that this can have a noticeable influence on …

Pheromonal Composition Of Two Species Of African Amblyomma Ticks: Similarities, Differences And Possible Species Specific Components, Thomas Lem Price Jr.

Biological Sciences Theses & Dissertations

Two species of bont ticks, Amblyomma hebraeum and Amblyomma variegatum, common to Africa have been studied to compare types and quantities of compounds known or believed to serve as components of the attraction-aggregation-attachment pheromone (AAAP). A complex of attraction, aggregation and attachment pheromones are used by these ticks to detect hosts, mates and perhaps minimize interspecific breeding. Solvent extraction of pheromone emitting ticks followed by Gas Chromatography and Mass Spectrometry revealed little difference in the composition of the AAAP in these two species. However, subtle differences in the relative makeup of the pheromonal blend are noted, suggesting that such differences …

A Study Of The Chlorination Products Of Methionine In Model Solutions And In Wastewater, D. Scott Winters

Chemistry & Biochemistry Theses & Dissertations

Model solutions of the amino acid methionine were chlorinated to seven chlorine-to-nitrogen (Cl₂/N) molar ratios. After 30 minutes, the solutions were analyzed by high performance liquid chromatography (HPLC). At a Cl₂/N molar ratio of 1, methionine sulfoxide was found to be the main product. At Cl₂/N molar ratios ≥ 2, a mixture of methionine sulfoxide, methionine sulfone, an unidentified sulfoxide (product 1), and N-chloro-3-(methylsulfonyl) propionaldimine are formed. These products were identified by comparison to synthesized standards which were characterized by ¹H-NMR and ¹³C-NMR nuclear magnetic resonance spectroscopy, ion trap mass spectroscopy, …

The Effect Of 6-Methoxybenzoxazolinone On Reproductive Condition In The Hispid Cotton Rat, Sigmodon Hispidus, Vera Lee Adams

Biological Sciences Theses & Dissertations

A non-estrogenic hormone, 6-methoxybenzoxazolinone (6-MBOA), found in young growing grasses, has been shown to be a reproductive initiator in several herbivorous rodents. However, the mechanism by which 6-MBOA initiates reproduction has not been determined. Many believe that 6-MBOA represents a reliable cue that the vegetative growing season has begun, but it is unknown whether this hormone is a primary cueing mechanism or if it works in conjunction with other environmental factors. Therefore, a controlled laboratory experiment was conducted using male and female Sigmodon hispidus, the hispid cotton rat, to determine whether different dosages of 6-MBOA (4μg, 40 …

Age And Growth Of Larval And Juvenile Atlantic Croaker, Micropogonias Undulatus, From The Middle Atlantic Bight And Estuarine Waters Of Virginia, Stephen W. Nixon

Biological Sciences Theses & Dissertations

Sagittal otoliths were used to determine the age and growth of 605 larval and juvenile Atlantic croaker, Micropogonias undulatus, collected in the Middle Atlantic Bight (MAB) and estuarine waters of Virginia. A Laird-Gompertz model (r2 = 0.95) was used to describe the growth of croaker up to 65 mm standard length (SL) and 142 days (t): S1_(t) = 2.657 Exp {4.656 [1-Exp (-0.008lt)]}; SL_(t) = standard length at day t. Generally, croaker collected inshore were larger and older than those collected offshore, indicating estuarine immigration from offshore spawning grounds. Back-calculated hatch-dates indicated spawning over an 8- month period …

Light Injection From An Active Cladding To The Core Of A Fiber Optic Fluorosensor, Alvin Leon Bryant

Electrical & Computer Engineering Theses & Dissertations

A fluorosensor works on the basis of light injection from the clad into the core of an optical fiber. The sensitivity of such a sensor depends on the efficiency of light injection. Conditions necessary for a high injection efficiency are experimentally determined. The refractive index difference between the core and the clad,ⁿcore ^-nclad, must be maximized to achieve a high injection efficiency. Since an air clad has the least refractive index, a bare core fiber will have a maximum efficiency. Standard optical fibers used for communication employ a minimum value for ⁿcore ^-nclad, in order …

Towards A Universal Nuclear Nonproliferation Treaty, T. P. Radhakrishnan

Graduate Program in International Studies Theses & Dissertations

The 1968 Treaty on the Nonproliferation of Nuclear Weapons (NPT) came into force in 1970 and expires in 1995. In 1995 an extension conference has to be convened to decide whether the treaty continues in force indefinitely or will be extended for an additional period or periods.

The treaty, cosponsored by the us, the USSR, and the UK, has 155 signatories, but a few countries like Israel, India and Pakistan have refused to be bound by it. They have done so mainly on the formal grounds that the treaty is structurally discriminatory between nuclear and nonnuclear weapons states.

What are …

The Impractical Ideal Costa Rica, The United States And Central America Reunification, 1902-1932, Donald R. Lam

Graduate Program in International Studies Theses & Dissertations

This thesis examines the motivations of Central American Unionists and the failure of their movement in the early years of the twentieth century. The existing literature attributes the failure of Central American unification during this era to U.S. policies meant to maintain a divided isthmus in order to economically and politically exploit the region. A closer analysis of the primary sources, however, reveals that union failed because of internal factors, and that Washington's actions generally favored efforts to rejoin the nations to reduce isthmian tensions. Attempts to reunite the republics failed because of regional and domestic political rivalries, weaknesses in …

Managerial Roles And Entrepreneurship In Non-Profit Urban Arts Agencies In Virginia, Beth Joan Novitch Rossheim

Theses and Dissertations in Urban Services - Urban Management

The future of the arts in Virginia depends on knowing how arts agencies are functioning and surviving at a time of resource decline. What roles do managers play in administering agencies? What business and management skills do managers use to maintain an agency and to relate to the community? How do managers handle cutbacks? Does entrepreneurship create more viable arts agencies?

Bivariate data analysis separated managers into four role groups: entrepreneur, administrator, artist, and caretaker, according to their perceived degree of programmatic creativity and documented access to organizational resources. Managerial role types were compared with management behaviors to discern significant …

The Implementation Of Neighborhood Conservation Projects In Portsmouth, Virginia, 1960-1990, Robert Brooke Albertson

Theses and Dissertations in Urban Services - Urban Management

The study describes and analyzes the implementation of federally-funded neighborhood conservation programs in two of Portsmouth, Virginia's oldest urban neighborhoods by addressing four research questions: (1) To what extent is there variation in the implementation of neighborhood conservation projects in differing neighborhood settings? What are the factors that account for such differences? (2) To what extent are the neighborhood conservation projects distributive or regulatory programs, and what forms of conflict and/or cooperation result from this? (3) What is the intergovernmental context of neighborhood conservation projects, and how does this affect the nature of bargaining and negotiation among governmental units? and …

A Comparison Of The Effectiveness Of Two Types Of Clinical Instruction On Selected Variables Among Urban Baccalaureate Nursing Students, Janice Parks Hylton

Health Services Research Dissertations

The purpose of this study was to provide baseline data regarding student perceptions of bureaucratic, professional, and service values and of instructors/preceptors as role models for each model of clinical supervision, traditional versus preceptored. A non-probability, convenience sample included 113 baccalaureate nursing students from two accredited programs in an urban area. Two instruments were used to identify student perceptions of bureaucratic, professional, and service values and of instructors/preceptors as role models. The results of the questionnaires revealed no significant differences between the students' perceptions of bureaucratic and service values and perceptions of instructors/preceptors as role models, Students' perceptions of professional …

Political Interference In Military Operations During The Anglo-Zulu War Of 1879, Thomas Max Lansford

History Theses & Dissertations

This work examines the degree and effect of the reluctant cooperation of the British government and its colonial agencies with the British army during the Anglo-Zulu War of 1879. While it is clear that there was no civilian conspiracy to interfere with the army, it is also clear that several of the policies of the government and its colonial agencies hindered army operations. The study is based on the War Office narrative of military operations, on Colonial and War Office correspondence, and on the memoirs and diaries of several participants.

Tobacco And Its Role In The Life Of The Confederacy, D. T. Smith

History Theses & Dissertations

This study examines the role that tobacco played in influencing Confederate policy during the American Civil War. Surprisingly, very little research has been done on this subject; historians have virtually ignored the influence of tobacco upon Southern economic interests between 1850 and 1870.

The southern tobacco-producing states grew 439,183,561 pounds of raw tobacco in 1860. Southern manufactured tobacco was worth $21,820,535 in 1860, and along with other agricultural products, especially cotton, played an important economic, political, and diplomatic role in the life of the Confederacy. The tobacco industry represented a very strong interest group in the Upper South during the …

A Multiple Case Study Of Selected Individuals Who Facilitate The Successful Adoption Of Environmental Public Policy, John H. Austin

Health Services Research Dissertations

The purpose of this study was to determine the personal and professional characteristics of successful individuals who have had a positive influence on the development of public policy concerning the environment. Additionally, which characteristics are most likely to enhance success and determine which of these characteristics might contribute to efforts toward developing public environmental policy in the future were investigated. The purpose was accomplished through the design and implementation of a multiple case study utilizing a qualitative research methodology. The sample for this study included six public servants who were identified as actively involved in affecting the development of public …

A Preliminary Study Of A Job Analytic Inventory Derived From A Behavioral Consistency Method For Assessing Intrinsic Motivation, William John Banis

Theses and Dissertations in Urban Services - Urban Management

The research question for this study asked if the Job Specifications Inventory (JSI) had acceptable internal reliability and an ability to differentiate among occupational groups. The JSI was designed to have subject matter experts rate the importance of skill, content, context, relationship and work focus requirements of jobs or occupations. The JSI used a taxonomy of 268 behavioral elements derived from the content analyses of satisfying achievements reported by a large, diverse clientele. A clinical-type behavioral consistency method was used to extract performance dimensions from clients' achievements to build the taxonomy. The achievement-based taxonomy was seen as potentially enhancing productivity …

Analysis Of The Proteoglycan Content In Fresh And Cryopreserved Porcine Cardiovascular Tissues, Yun Hee Shon

Theses and Dissertations in Biomedical Sciences

The purpose of this research was to study the effects of cryopreservation on the proteoglycan (PG) and mineral content of aorta conduit tissue. Proteoglycans from fresh and cryopreserved porcine aorta conduit tissues were isolated by extraction with 4 M guanidine (Gdn) - hydrochloride (HCl) for 48 hours. Quantitative analysis of extracted proteoglycans revealed that the content of proteoglycan material from cryopreserved tissue, measured as uronate and protein per unit weight of wet tissue, was similar to that from fresh tissue. Gel permeation column chromatography studies suggested that proteoglycans present in three CsCl fractions from cryopreserved tissues had molecular weights similar …

Cross-Cultural Issues In The Management Of German-Owned Business Subsidiaries In Hampton Roads, Teja Ulrich

Engineering Management & Systems Engineering Theses & Dissertations

'Culture' can be described as patterns of thinking, feeling and acting that distinguish one cultural group from another. Cultural diversity is therefore likely to introduce variety to organizations in which individuals from different national backgrounds are working together. Although this variety bears the potential for an improvement of the cognitive development in the organizations, managers of multicultural business organizations tend to perceive cultural diversity as a disadvantage. This thesis attempts to identify the impact of cultural differences between Germans and Americans on organizations in which German managers work with American employees. German managers of eight business subsidiaries in the Hampton …

Grid Sensitivity For Aerodynamic Optimization And Flow Analysis, Ideen Sadrehaghighi

Mechanical & Aerospace Engineering Theses & Dissertations

An algorithm is developed to obtain the grid sensitivity with respect to design parameters for aerodynamic optimization. Two distinct parameterization procedures are developed for investigating the grid sensitivity with respect to design parameters of a wing-section as an example. The first procedure is based on traditional (physical) relations defining NACA four-digit wing-sections. The second is advocating a novel (geometrical) parameterization using spline functions such as NURBS (Non-Uniform Rational B-Splines) for defining the wing-section geometry. An inter-active algebraic grid generation technique, known as Two-Boundary Grid Generation (TBGG) is employed to generate C-type grids around wing-sections. The grid sensitivity of the domain …

The Influence Of Reynolds Number And Atmospheric Effects On Aircraft Wake Vortices Near The Ground, Zhongquan Charlie Zheng

Mechanical & Aerospace Engineering Theses & Dissertations

Aircraft wakes represent potential hazards which can control aircraft spacing and thus limit airport capacity. Wake vortex trajectories and strengths are altered radically by interactions with the ground plane and by atmospheric conditions. This work has been concerned with developing more accurate numerical predictions. A two-dimensional, unsteady numerical-theoretical study is presented which has included viscous effects, the influence of stratification, crosswind and turbulence on vortex behavior near the ground plane, using a vorticity-streamfunction formulation.

A two-parameter perturbation procedure has been developed which uses analytic solutions for the initial flow field to accommodate the ground effect region in the numerical simulation. …

Competitive Enzyme Immunoassay By Polyclonal Antibodies Against Organophosphorus Pesticides, Kuo-Lan Wen

Theses and Dissertations in Biomedical Sciences

Organophosphorus compounds (OPs) comprise one of the major classes of pesticides in use today because they are highly effective and less toxic. Because of their extensive use, there is a need for monitoring OPs in water and vegetables. Gas chromatography (GC) is the usual method for OPs screening, but it is time-consuming and has the high cost of instrumentation. The goal of this project was to find an easy method which was sensitive and had less instrumentation required to test OPs.

Microwells and microtubes were utilized as the solid-phase immobilization for the development of an enzyme immunoassay for OPs. A …