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Biostratigraphic Analysis Of Southern Florida's Plio-Pleistocene Shell Beds, Dalton L. Rasmussen

OES Theses and Dissertations

Four molluscan assemblage zones in southern Florida corresponding to the Pinecrest Sand Member of the Tamiami Formation, and the Caloosahatchee, Bermont and Fort Thompson shell beds were identified following quantitative and qualitative analyses of the fossil molluscan fauna. Twenty-eight bulk sediment samples collected from 16 localities across southern Florida were processed for fossil material, and yielded nearly 60,000 specimens belonging to 311 species. A Q-mode cluster analysis compared sediment samples on the basis of 188 species whose abundances had been converted to binary presence-absence form. The cluster analysis was run four times using the Jaccard and Dice similarity coefficients as …

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 …

Elevation As A Control Of Boulder Stream Formation In The Blue Ridge Province Of Virginia, Marc D. Zamkotowicz

OES Theses and Dissertations

Within four study areas in the Blue Ridge Mountains of Virginia, boulder streams formed by periglacial processes carpet the bottoms of most high-altitude first-order valleys. The geomorphic indicators of periglacial formation in these long, linear accumulations of bouldery colluvium - the presence of vertical clasts, gradational upper contacts with talus deposits, confinement within valleys, and hump-like cross sectional profiles - were present in all areas mapped and in most individual boulder streams. The minimum critical elevation for boulder stream formation increases from north to south across Virginia, from 150 m in elevation in northern Virginia to 1500 m in southwestern …

Influence Of Physics On The Distribution Of Ichthyoplankton Across The Chesapeake Bay Plume, Christian S. Reiss

OES Theses and Dissertations

Most marine fish have retained pelagic larval stages that are spawned away from juvenile habitats. Physical and biological processes on a number of scales may affect larval survival. Mesoscale features like estuarine or riverine plumes and fronts are thought to affect larval survival by transporting larvae to juvenile habitats or by retaining larvae in favorable developmental habitats. It is likely that these features are major contributors in the regulation of shelf-spawned estuarine-dependent taxa.

This study examined how physical oceanographic features affected the spatial distribution of ichthyoplankton across the Chesapeake Bay Plume. Larval surveys were conducted across the shelf and within …

Broadband Dynamic Modification Using Feedforward Control, Kendeas Antonis Karantonis

Mechanical & Aerospace Engineering Theses & Dissertations

The use of feedforward control for dynamic modification is relatively new to the area of structural vibration control. In this thesis the disturbance path dynamics of a flexible aluminum beam, pinned at both ends and under the influence of broadband excitation inputs, are modified through the use of feedforward control. The ideal algebraically determined feedforward control method for response cancellation is first presented. Theoretically, this compensator modifies the disturbance path dynamics to any desired behavior. This ideal algebraic approach can only be used for minimum phase systems. In non-minimum phase systems, right half s-plane plant zeros emerge as unstable poles …

Virginia's Eastern Shore High School Students: Factors That May Impact Their Educational Aspirations, Valdimir Demont Handy

Sociology & Criminal Justice Theses & Dissertations

Using 1995 Survey data collected from high school students on Virginia's Eastern Shore, this thesis investigated whether or not self-esteem and perceived parental expectations play a role in the educational aspirations of rural high school students. Results demonstrated that self-esteem and perceived parental expectations are both positively related to students' educational aspirations. Caucasians and females were found to have higher educational aspirations than their counterparts. Results also indicated that the relationship between self-esteem, perceived parental expectations, and students' educational aspirations does not vary significantly across ethnicity or gender in this rural population. The information from this study, coupled with previous …

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 …

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 …

The Effects Of Organic Matter Rich Topsoil On The Germination Growth And Metal Uptake Of Corn (Zea Mays) Grown In Flue Dust Contaminated Soil, Christopher Allen Impellitteri

OES Theses and Dissertations

The large biomass of corn (Zea mays) and promising results from a previous experiment (Chlopecka and Adriano, 1995) concerning metal uptake by corn indicate that corn may be a good candidate for phytoremediation of trace metal contaminated soil. Appling soil (acid, thermic, typic paleudult) was treated with increasing levels of a metal rich flue dust based on Zn concentration (0, 150, 300, 600, 1200, and 2400 mg/kg). Four replicates at each Zn treatment level were either limed to pH 6.3-6.5 and covered with a two inch thick layer of organic matter rich topsoil (OM), unlimed and covered with …

40Ar/39 Ar Geochronology Of The Lowland Creek Volcanic Field And Its Temporal Relations With Other Eocene Volcanic Areas, Vladimir Olegovich Ispolatov

OES Theses and Dissertations

Exposures of the Eocene Lowland Creek Volcanics (LCV) cover an area of 2000 km² in southwestern Montana, and consist of basal elastic deposits, felsic tuffs, and felsic and intermediate lavas with an aggregate thickness of about 2 km. New ⁴⁰Ar/³⁹Ar dates show that volcanic activity lasted for at least 4.2 million years (52.7- 48.5 Ma), or even longer (4.5-4.7 million years: from 53.0-53.2 Ma to 48.5 Ma). During evolution of the volcanic field, early explosive volcanism was gradually replaced by extrusive activity. During the transition period (52.7-51.5 Ma), the two volcanic styles coexisted.

The evolution of …

Middle Shoreface Intervals: Evidence Of Barred Nearshore Systems In He Stratigraphic Record, James V. Gravette

OES Theses and Dissertations

An interpretation for middle shoreface (MSF) intervals was developed by comparing MSF intervals from the Upper Cretaceous (Campanian) Blackhawk Formation, east-central Utah, with conceptual models proposed for modern nearshore areas. Specifically, MSF intervals identified within the Sunnyside Member were compared with MSF intervals identified within the Spring Canyon (Kamola and Van Wagoner, 1995) and the Aberdeen (Kamola, unpublished data) members.

A comparison of MSF interval data revealed that MSF intervals occur stratigraphically between upper and lower shore face deposits, disrupting the standard vertical succession for nearshore marine deposits (consisting of offshore, lower shore face, upper shore face, and foreshore deposits). …

High Resolution Wavelength Modulation Spectroscopy For Precise Gaseous Characterization, Audra Michiele Bullock

Electrical & Computer Engineering Theses & Dissertations

Wavelength modulation spectroscopy is a highly sensitive, non-intrusive technique for probing gaseous species. Parameters such as velocity, density, and temperature can be measured and monitored with a high degree of precision. In addition, with the use of this technique multiple molecular species may be identified with a single laser probe. This measurement technique utilizes the well-known principles of modulation absorption spectroscopy in a novel way.

The research focuses on harmonic detection and the advantages gained by performing detection at higher harmonics, those greater than the commonly used second harmonic. We show that there is an increase in the sensitivity to …

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 …

Analysis And Testing Of Plates With Piezoelectric Sensors And Actuators, Jeffrey S. Bevan

Mechanical & Aerospace Engineering Theses & Dissertations

Piezoelectric material inherently possesses coupling between electrostatics and structural dynamics. Utilizing linear piezoelectric theory results in an intrinsically coupled pair of piezoelectric constitutive equations. One set describes the direct piezoelectric effect, where strains produce an electric field, and the other set describes the converse effect, where an applied electrical field produces strain. The purpose of this study is to compare the finite element analysis and experiments of a thin plate with bonded piezoelectric material.

Since an isotropic plate in combination with a thin piezoelectric layer constitutes a laminated composite, the classical laminate plate theory is used in the formulation to …

Input Design For Systems Under Identification Using Indirect And Direct Methods, Marco P. Schoen

Mechanical & Aerospace Engineering Theses & Dissertations

The motivation for system identification can be manifold. In this work, the provocation to identify unknown system characteristics is derived from the control engineering point of view. That is, one intends to design a control strategy based on the identified system properties. The used system identification methods are the Open-Loop Kalman filter System Identification method (OKID) and the Closed-Loop System Identification method (CLID). It is shown that the quantitative largest error of the system identification is given by its model representation, that is the attempt to describe a system with model parameters which poses a linear relationship with the input/output …

Post-Surgical Passive Response Of Local Environment To Primary Tumor Removal, J. A. Adam, C. Bellomo

Mathematics & Statistics Faculty Publications

Prompted by recent clinical observations on the phenomenon of metastasis inhibition by an angiogenesis inhibitor, a mathematical model is developed to describe the post-surgical response of the local environment to the “surgical” removal of a spherical tumor in an infinite homogeneous domain. The primary tumor is postulated to be a source of growth inhibitor prior to its removal at t = 0; the resulting relaxation wave arriving from the disturbed (previously steady) state is studied, closed form analytic solutions are derived, and the asymptotic speed of the pulse is estimated to be about 2 × 10⁻⁴ cm/sec for the …

Limiting Spheroid Size As A Function Of Growth Factor Source Location, J. A. Adam, K. Y. Ward

Mathematics & Statistics Faculty Publications

Solutions C(r) of the time-independent nonhomogeneous diffusion equation for three different piecewise-uniform source terms are used to examine the limiting size of multicell spheroids using a simple model which reproduces concentration-dependent mitotic behavior. A condition is derived under which nontrivial solutions do not exist (in all three cases), and a condition for the existence of a unique nontrivial solution is established for the case of growth-modifying factor (GMF) production throughout the spheroid. Qualitative behavior of the limiting size is established as a function of various physiological parameters. Of fundamental importance is the assumed GMF concentration threshold θ, …

Antiplane Shear Of A Strip Containing A Staggered Array Of Rigid Line Inclusions, G. Kerr, G. Melrose, J. Tweed

Mathematics & Statistics Faculty Publications

Motivated by the increased use of fibre-reinforced materials, we illustrate how the effective elastic modulus of an isotropic and homogeneous material can be increased by the insertion of rigid inclusions. Specifically we consider the two-dimensional antiplane shear problem for a strip of material. The strip is reinforced by introducing two sets of ribbon-like, rigid inclusions perpendicular to the faces of the strip. The strip is then subjected to a prescribed uniform displacement difference between its faces, see Figure 1. it should be noted that the problem posed is equivalent to that of the uniform antiplane shear problem for an infinite …

Hoffman’S Error Bounds And Uniform Lipschitz Continuity Of Best L(P) -Approximations, H. Berens, M. Finzel, W. Li, Y. Xu

Mathematics & Statistics Faculty Publications

In a central paper on smoothness of best approximation in 1968 R. Holmes and B. Kripke proved among others that on ℝⁿ, endowed with the l_ρ-norm, 1< p < ∞, the metric projection onto a given linear subspace is Lipschitz continuous where the Lipschitz constant depended on the parameter p. Using Hoffman’s Error Bounds as a principal tool we prove uniform Lipschitz continuity of best l_ρ -ap- proximations. As a consequence, we reprove and prove, respectively, Lipschitz. continuity of the strict best approximation (sba, p = ∞ and of the natural best approximation (nba, p = 1.

A Dual Approach To Constrained Interpolation From A Convex Subset Of Hilbert Space, Frank Deutsch, Wu Li, Joseph D. Ward

Mathematics & Statistics Faculty Publications

Many interesting and important problems of best approximationare included in (or can be reduced to) one of the followingtype: in a Hilbert spaceX, find the best approximationPK(x) to anyx∈Xfrom the setK≔C∩A−1(b),whereCis a closed convex subset ofX,Ais a bounded linearoperator fromXinto a finite-dimensional Hilbert spaceY, andb∈Y. The main point of this paper is to show thatPK(x)isidenticaltoPC(x+A*y …

The Hadamard Matroid And An Anomaly In Its Single Element Extensions, C. H. Cooke

Mathematics & Statistics Faculty Publications

A nonstandard vector space is formulated, whose bases afford a representation of what is called a Hadamard matroid, M_p. For prime p, existence of M_p is equivalent to the existence of both a classical Hadamard matrix H(p,p) and a certain affine resolvable, balanced incomplete block design AR(p). An anomaly in the representable single element extension of a Hadamard matroid is discussed.

A Modeling Study Of The Effects Of Size- And Depth-Dependent Predation On Larval Survival, Margaret M. Dekshenieks, Eileen E. Hofmann, John M. Klinck, Eric N. Powell

CCPO Publications

The form of the predation pressure experienced by larval stages of marine invertebrates is largely unknown. However, it is believed that the type, timing and rate of larval predation are critical in determining recruitment to adult populations. In this study, a time and depth-dependent model of the growth and behavior of larvae of the Eastern oyster, Crassostrea virginica, was used to investigate the effects of different forms of size-and depth-dependent predation on larval survivorship. The simulated larval survival for a cohort experiencing size-dependent predation showed that the greatest percent of the cohort survived to competent settlement size when the …

Factors Affecting The Recruitment Of Juvenile Caribbean Spiny Lobsters Dwelling In Macroalgae, Mark J. Butler Iv, William F. Herrnkind, John H. Hunt

Biological Sciences Faculty Publications

In south Florida, Caribbean spiny lobsters (Panulirus argus) settle and spend their first few months in macroalgae or seagrass. After a few months, these ''algal-phase'' juveniles emerge from vegetation and, as ''postalgal-phase'' juveniles, seek refuge in crevices, often dwelling in groups. The importance of crevice shelters in determining the abundance of postalgal-phase juvenile spiny lobsters has been studied but we know little about the processes affecting lobster distribution and survival during their cryptic algal-dwelling phase. We found that postlarval supply varied independently of changes in the structure of macroalgal settlement habitat. For this reason, postlarval supply alone can not reliably …

Fluxes Of Copper-Complexing Ligands From Estuarine Sediments, Stephen A. Skrabal, John R. Donat, David J. Burdige

OES Faculty Publications

Most studies of the organic complexation of Cu in natural waters have focused on distributions and processes in the water column, where a significant fraction of Cu-complexing ligands may be biologically produced. We present direct evidence for a flux of Cu-complexing ligands from estuarine sediments, demonstrating that sediments are a significant, yet previously unrecognized source of the ligands. Fluxes of Cu-complexing ligands from Chesapeake Bay sediments range from 300 to 1,200 nmol m^-2 d^-1, exceeding fluxes of total dissolved Cu by 3->40-fold, suggesting that any Cu fluxing from the sediments is likely to be organically complexed. …

A Study To Determine The Differences In Undergraduate Technology Education Teacher Preparation Curricula In Virginia, Cecil Stanley Burgett

OTS Master's Level Projects & Papers

These goals were analyzed to detect the specific variances among the four technology education certification programs in Virginia: 1. How are the Virginia technology education teacher preparation programs accredited? 2. What is the pedagogical curriculum in undergraduate technology education teacher preparation at each university? 3. What is the technical content of the four Virginia undergraduate technology education teacher preparation programs? 4. What are the field experiences of the four Virginia undergraduate technology education teacher preparation programs? 5. What are the general education requirements of each program?

Teacher's Attitudes Of Block Scheduling And Lesson Preparation Quality/Time In Two Virginia Beach City Public High Schools, Christin G. Browning

OTS Master's Level Projects & Papers

The problem of the study was to compare teacher's lesson preparation time and utilization of alternative teaching methods during block scheduling as compared to the traditional seven-bell schedule at Kempsville and Princess Anne High Schools in Virginia Beach, Virginia

A Study To Examine Patterns And Performance Trends Among Black And White School Students On A National Level From The 1970s To The 1990s, Otis L. Miller

OTS Master's Level Projects & Papers

This study will attempt to accomplish the following research goals: 1. Explore some of the characteristics of low self-esteem or image and motivation among black school children; 2. Examine the academic performance trends between black and white school children by making a comparison between dropout rates, science scores, mathematics scores, and reading scores; 3. Analyze the overall effectiveness of public school desegregation.

A Descriptive Study Of The Trends And Issues In Vocational And Technical Education In The Virginia Community College System, Angelia M. Comstock

OTS Master's Level Projects & Papers

With the purpose of determining the current issues and tends in vocational and technical education at Virginia's community colleges, this study was developed with three research questions (goals) in mind. They are: 1. To research the historical foundations of curriculum offerings in Virginia's community colleges; 2. To research national issues and trends affecting vocational and technical education in community colleges; 3. To compare the issues and trends in Virginia's community colleges as perceived by division chairs and selected deans with national issues and trends as identified from a review of the literature.

A Study On The Feasibility Of Implementing Advanced Placement Courses In The Field Of Technology Education, Donald S. Luebbecke, Mark A. Mcgrath

OTS Master's Level Projects & Papers

This study was developed with three goals in mind: 1. To determine the opinions of state supervisors/directors of Technology Education concerning the establishment of an AP program for Technology Education; 2. To request recommendations or nominations for AP credit content areas applicable to Technology Education from state supervisors/directors; 3. To determine the procedures to be followed by the Technology Education profession and The College Board to establish and implement a Technology Education AP program.

A Study To Examine The Reasons For Licensure Preferences By Mctp Students, James S. Mcneill

OTS Master's Level Projects & Papers

The following goals were used to direct this study: 1. Determine the exact reason for the middle school licensure preference by MCTP graduate students; 2. Determine if the age of their prospective students was a reason for their preference for middle school licensure; 3. Determine if MCTP graduate students choose middle school licensure because their military and undergraduate experience lends itself best to this area of teaching.