Digital Commons Network^™

Effects Of El Nino On Local Hydrography And Growth Of The Giant Kelp, Macrocystis Pyrifera, At Santa Catalina Island, California, Richard C. Zimmerman, Deborah L. Robertson

OES Faculty Publications

Deepened isotherms associated with El Niño resulted in severe nutrient limitation and very low kelp productivity during the last half of 1983. Frond growth rates were so low that terminal blades formed before reaching the surface, eliminating the canopy. Frond initiation rates were also extremely low, resulting in significant reductions in mean plant size. Plants growing above 10m were more severely affected than plants at 20m. Nutrient pulses associated with internal waves are thus critical for survival of Macrocystis pyrifera in nutritionally marginal habitats in Southern California.

Microbial Manganese Reduction By Enrichment Cultures From Coastal Marine Sediments, David J. Burdige, Kenneth H. Nealson

OES Faculty Publications

Manganese reduction was catalyzed by enrichment cultures of anaerobic bacteria obtained from coastal marine sediments. In the absence of oxygen, these enrichment cultures reduced manganates when grown on either lactate, succinate, or acetate in both sulfate-free and sulfate-containing artificial seawaters. Sodium azide as well as oxygen completely inhibited microbial manganese reduction by these enrichment cultures, whereas molybdate had no effect on them. The addition of nitrate to the medium slightly decreased the rate of Mn²⁺ production by these enrichment cultures. These findings are consistent with the hypothesis that the manganese-reducing organisms in these enrichment cultures use manganates as terminal …

The Uneasy Triangle The Impact Of China On U.S.-Soviet Relations In The 1970'S Salt: A Case Study, Karen Elizabeth Toenjes

Graduate Program in International Studies Theses & Dissertations

No abstract.

Brochure: 7th Annual Literary Festival, 1984, Publications Department, Old Dominion University

7th Annual Literary Festival at ODU: October 1-4, 1984

No abstract provided.

The Effects Of X-Irradiation On The Metamorphosis And Budding Of Aurelia Aurita, Michael John Prokopchak

OES Theses and Dissertations

With the aid of the Aurelia Metamorphosis Test System, the acute or subtle morphological and behavioral effects of irradiation on the Norfolk Aurelia aurita were described and the sensitivity to X-irradiation of those organisms receiving thyroxine and those not receiving thyroxine was compared. Levels of radiation were 0 (control), 5,000, 10,000, 15,000, 20,000 and 40,000 rads. Morphology of the ephyrae, statolith and rhopalia numbers were recorded using the light microscope, Developmental abnormalities of the scyphistomae and ephyrae were recorded with the scanning electron microscope and light microscope. Two major findings from this investigation were the absence of rhopalia and statoliths …

Groundwater Management By Linear Programming, Seungho Song

Civil & Environmental Engineering Theses & Dissertations

Three hydraulic optimization models are developed. These models combine the finite difference equations of two-dimensional groundwater flow in composite aquifers with various linear programming techniques. The hydraulic submodel employed in these hydraulic optimization models is so versatile that it accounts for time varying pumpage, leaky artesian conditions, a variety of boundary conditions, induced infiltrations from streams or rivers, and conversion from artesian to water table conditions. The objective of submodel 1 is to maximize the total hydraulic head from pumping wells at the end of a study period. The objective of submodel 2 is the same as submodel 1, but …

Demographic Analysis And Microhabitat Relationships Of A Small Mammal Community In Clearings Of The Great Dismal Swamp, Jean Ferguson Stankavich

Biological Sciences Theses & Dissertations

Small mammals were trapped for 14 months on two grids located within a powerline right-of-way in the Great Dismal Swamp National Wildlife Refuge. During 12,354 trap nights, individuals of 10 different species were captured. They included, from highest to lowest density, Reithrodontomys humulis, Ochrotomys nuttalli, Peromyscus leucopus, Blarina brevicauda, Synaptomys cooperi, Microtus pennsylvanicus, Microtus pinetorum, Sigmodon hispidus, Mus musculus and Oryzomys palustris. The demography (densities, reproduction, home range and dispersal) of each species was analyzed when possible. Most of the species were present in relatively low densities, with a number being captured only during the latter months of the study. …

Age Tracking Performance And The Measurement Of Workload By A Secondary Tasks, Manuel Francisco Diaz

Psychology Theses & Dissertations

The purpose of this study was to investigate age differences in tracking performance and in the amount of workload imposed by the tracking task. Twelve subjects between the ages of 18 and 22, and 12 subjects between the ages of 48 and 67 performed a serial, choice-reaction-time task alone and concurrently with a pursuit rotor tracking task. The choice reaction time task served as the secondary task and the pursuit rotor tracking task as the primary task. Primary task performance was measured by time on target and number of tracking errors, and the secondary task by choice reaction time and …

A Survey Of Burnout Among Dental Hygiene Educators, Sandra Boggs Ricks

Dental Hygiene Theses & Dissertations

A survey was conducted on 159 full-time dental hygiene educators in order to collect data on job satisfaction, morale, and perceived institutional/program effectiveness. Educators were chosen for the study by cluster sampling from two- and four-year accredited dental hygiene programs in the United States. The programs were selected at random from stratified groups according to type of institutional setting. Participants were asked to complete a questionnaire which contained four major sections: demographic data, job satisfaction, institutional/program effectiveness, and feelings related to their position. Findings were analyzed utilizing contingency tables and Chi-Square analysis. No attempt was made to establish a cause …

Numerical Experiments With The Quasigeostrophic Potential-Vorticity Equation, Peter L. Spence

OES Theses and Dissertations

A method is developed to model the circulation of a barotropic, 8-plane ocean under an imposed steady wind stress. The model includes the effect of both horizontal and vertical friction along with nonlinear advection of vorticity. Implementing the method involves solving the unsteady quasigeostrophic potential-vorticity equation using a compact finite difference scheme (Gatski, Grosch, and Rose, 1982).

Once developed, this model is used in four separate numerical experiments. In each experiment, a model ocean with an initial flow field is driven to a steady state solution. Vertical viscosity is held constant in the first three experiments while lateral viscosity is …

Tectonic Implications Of Late Tertiary Strata Exposed Along The Piankatank River, Eastern Virginia, Daniel Stephen Lane

OES Theses and Dissertations

Biostratigraphic analysis of Late Miocene and Pliocene strata along the Piankatank River in eastern Virginia exposes a juxtaposition of the Eastover and Yorktown Formations. This structure is situated on a NE trending alignment of geological, geomorphic, and geophysical features which run from southern Virginia to northern Delaware. Tectonic jointing in isolated sandstone bodies and fracture controlled drainage patterns provide further evidence of post-middle Pliocene tectonism in the region. The lateral spacing of this structure from the Stafford and Brandywine fault zones and other linear features on the Coastal Plain strongly implies that a structural similarity exists between the Piankatank structure …

Investigation Of Flow Phenomena In A Repetitively-Pulsed Gas Flow Switch, Shivakumar Srinivasan

Mechanical & Aerospace Engineering Theses & Dissertations

A two-dimensional, unsteady numerical model for analyzing the characteristics of gas flowing through a gas blown spark gap switch has been developed. The computational model is governed by the conservation equations of mass, momentum and energy in an inviscid, non-conducting, perfect, compressible fluid. The governing equations have been solved by using MacCormack's finite volume technique. The effects of rapid gas heating and subsequent changes in the fluid properties of the gas are examined in the high-pressure spark gap switch. The gas temperature, expansion velocity, density and pressure are calculated as functions of time. Air is the dielectric flowing through the …

Design Of Infrasound-Detection System Via Adaptive Lmstde Algorithm, Camille S. Khalaf

Electrical & Computer Engineering Theses & Dissertations

A proposed solution to an aviation safety problem is based on passive detection of turbulent weather phenomena through their infrasonic emission. This thesis describes a system design that is adequate for detection and bearing evaluation of infrasounds. An array of four sensors, with the appropriate hardware, is used for the detection part. Bearing evaluation is based on estimates of time delays between sensor outputs. The generalized cross correlation (GCC), as the conventional time-delay estimation (TOE) method, is first reviewed. An adaptive TUt approach, using the least mean square (LMS) algorithm, is then discussed. A comparison between the two techniques is …

Stratigraphy And Textural Analyses Of A Beach Ridge Complex, Cape Henry, Virginia, Daniel Leland Oyler

OES Theses and Dissertations

Eight lithological units, documented from the analyses of 26 boreholes, comprise five laterally extensive horizons in the subsurface of Cape Henry, Virginia. Interpretations of the environments of deposition for those units are based upon textural and compositional features, fossils, thickness and distribution of strata, and previous reports about late Tertiary and Quaternary deposits in nearby areas. The incised, Pliocene Chowan River Formation (Unit H) underlies Pleistocene Units F and G which are concentrated in a buried river valley beneath Cape Henry. Estuarine Units D and E resulted from a marine transgression of the study area during the early Holocene. The …

The Gift Of The Gods: The Impact Of The Korean War On Japan, John P. Bowen

Graduate Program in International Studies Theses & Dissertations

The Korean War was a benchmark in the modern history of Japan. It became a catalyst for political action, and the fountainhead of the "economic miracle" that raised Japan once again to a prominent position among nations. The Korean War helped solve many political problems, including the tricky question of a peace treaty. It confirmed Japan's commitment to a no-war constitution. It also permitted the Japanese government to relax the restrictions imposed by occupation authorities. The war created a fortuitous economic stimulus that permitted Japan to emerge from the recessionary period that followed World War II and to establish the …

Determination Of The Internal Rotational Energy Of Gaseous 1,2-Dichloroethane In An Argon Matrix Using Fourier Transform Spectroscopy, Susan Lynn Clarke

Chemistry & Biochemistry Theses & Dissertations

A sample cell and delivery system for rapid matrix isolation of gas mixtures at constant gas temperature was designed and evaluated. The rotational energy differences of 1,2-dichlorosthane and of its deuterium compound wars then determined to test this technique.

The rotational energy barriers calculated from Boltzman plots of ths gases at different temperatures were; 1.21 + 0.38 keel/mole, 1.33 + 0.70 Real/mole, and 1.12 + 0.45 kcal/mole for the CH2 wagging„ C-Cl stretching and CD₂ wagging modes respectively. These values were in good agreement with previously published values.

These results allowed evaluation of this apparatus and experimental design and …

Task Performances As Functions Of Level Of Processing, Morningness-Eveningness, Time Of Day, And Gender, Georgia Kathryn Green

Psychology Theses & Dissertations

This study was undertaken to examine the relations between human circadian activity patterns and information processing. Eighty subjects selected on the basis of gender and circadian type performed a digit-sequence task and an analogies task in either a morning or an afternoon condition, having previously completed the Horne and Ostberg (1976) circadian type questionnaire and the Schmeck (1983) Inventory of Learning Processes. A significant Gender x Circadian Type x Time-of-Day Condition interaction was found for digit-sequence task performance, with female subjects' performances exhibiting morning condition superiority for morning types but evening condition superiority for evening types. Time and gender effects …

Studies On The Interference Of Wings And Propeller Slipstreams, Ramadas K. Prabhu

Mechanical & Aerospace Engineering Theses & Dissertations

The small disturbance potential flow theory is applied to determine the lift of an airfoil in a nonuniform parallel stream. The given stream is replaced by an equivalent stream with a certain number of velocity discontinuities, and the influence of these discontinuities is obtained by the method of images. Next, this method is extended to the problem of an airfoil in a nonuniform stream of smooth velocity profile. This model allows perturbation velocity potential in a rotational undisturbed stream. A comparison of these results with numerical solutions of Euler equations indicates that, although approximate, the present method provides useful information …

Suboptimal Algorithms For Improvement Of Pipeline Through Insertion Of Delays, Sukhamoy Som

Electrical & Computer Engineering Theses & Dissertations

Pipelining is now widely used in the design of high speed processors in order to overcome the intrinsic speed limitations imposed by the technology. For a good performance and avoidance of internal conflicts, the concurrent operations within different subunits of a pipeline architecture should be properly scheduled This scheduling problem is known to be intrinsically difficult" and a member of the "NP complete class of problems. The aim of this thesis is to develop heuristic suboptimal algorithms whose execution time is a polynomial function of the number of items to be scheduled. Insertion of delay is used as a basic …

A Comparison Of Parenting Profiles Of Adolescent Mothers, Willar F. White-Parson

Theses and Dissertations in Urban Services - Urban Education

Statement of Problem. How do parenting profiles of adolescent mothers who attended an alternative school for pregnant students compare with adolescent mothers who did not attend this school?

Purpose. The purpose of this study was to compare the parenting perceptions of adolescent mothers who attended an alternative school for pregnant students and adolescent mothers who did not attend this school.

Procedure and Methods. The sample for this quasi-experimental study consisted of twenty volunteers who were enrolled in an alternative school and twenty volunteers who were admitted to a general hospital in Norfolk, Virginia. The school samples was the experimental group …

Combined Forced And Free Convection In The Trombe Wall Channel, Jim Ginchaun Huang

Mechanical & Aerospace Engineering Theses & Dissertations

A vertical channel connected by horizontal exit and entrance segments is simulated and represents a flow passage for a Trombe wall solar collector. The two-dimensional combined forced and free convection mode is investigated for the laminar regime. The vertical walls of the channel are maintained at a constant but different temperature while horizontal walls are insulated. A finite difference method using up-wind differencing for the non-linear convective terms and central differencing for the second order derivatives is employed to solve the governing differential equations for mass, momentum, and energy balances. The solution is obtained for stream function, vorticity, and temperature …

Estimating The Parameters Of Truncated Distributions, Mukul Mohan Mittal

Mathematics & Statistics Theses & Dissertations

The problem considered here is the estimation of the parameters of some special truncated distributions. If the sample observations are restricted to the interval {O, T} with T known, then it is well known in the literature that the method of maximum likelihood fails to provide a finite estimate, for the mean of an exponential distribution, whenever the sample mean is greater than T/2 (Deemer and Votaw, 1955, Ann. Math. Statist. 26, 498-504). Not so well known is the nonexistence of the maximum likelihood estimator (m.l.e.), under certain conditions, for the scale parameter of a gamma distribution from a truncated …

Fourier Series Analysis Of The Relationship Of Morphologic Variations And Bathymetry In Recent Bolivina (Foraminiferida) From The Northwestern Gulf Of Mexico, Anthony Cavedo Gary

OES Theses and Dissertations

Automated video digitization and closed-form Fourier series analysis were used to investigate the applicability of benthic foraminiferal test morphology for paleo-bathymetric/paleoenvironmental reconstructions. Sample relationships and harmonics with the greatest power for discriminating between samples were determined using canonical discriminant analysis. Samples were eleven short cores obtained from the northwestern Gulf of Mexico. Three species of Bolivina were analyzed, B. albatrossi, B. lowmani, and B. subspinescens.

Results show populations of Bolivina albatrossi from the upper bathyal and upper-middle bathyal zones to have more triangular tests and lobulate chambers than lower-middle and lower bathyal zone populations. Specimens of Bolivina subspinescens …

The Spatial And Temporal Distribution Of The Larvae Of Sympatric Pagurid Hermit Crabs (Decapoda, Anomura) In Virginian Estaurine And Coastal Waters, Philip Wesley Sadler

OES Theses and Dissertations

Thirteen stations were occupied at two - week intervals from May through September 1980 within the York River, lower Chesapeake Bay depths encompassing the entire water column.

Three species of pagurids were identified: Pagurus longicarpus, P. pollicaris, and P. annulipes. The larvae of P. annulipes had not been previously identified from Virginian waters. The shapes of the antennae of P. pollicaris and P. annulipes weredistinctive, allowing rapid identification of these larvae. The shapes of the uropods were found to be useful in distinguishingthe glaucothoe· of P. longicarpus from P. annulipes. The larvae of these species …

Implementation Of Uniform Perturbation Method For Potential Flow Past Axisymmetric And Two-Dimensional Bodies, Tin Chee Wong

Mechanical & Aerospace Engineering Theses & Dissertations

The aerodynamic characteristics of potential flow past an axisymmetric slender body and a thin airfoil are calculated by using a uniform perturbation analysis method. The method is based on the superposition of potentials of point singularities distributed inside the body. The strength distribution satisfies a linear integral equation by enforcing the flow tangency condition on the surface of the body. The complete uniform asymptotic expansion of its solution is obtained with respect to the slenderness ratio by modifying and adapting an existing technique. Results calculated by the perturbation analysis method are compared with the existing surface-singularity-panel method and some available …

Determinants Of Variation In Avian Mobbing Behavior, Charles Ray Chandler Jr.

Biological Sciences Theses & Dissertations

Using three combinations of two experimental stimuli, I initiated mobbing behavior in various species of birds. The objectives of this research were to test the effects of stimuli on mobbing, the predictions of the hypothesis that mobbing functions to drive a predator away, and the effect of other species and individuals on the mobbing behavior of a bird. Mobbing experiments were conducted in a variety of habitats and locations from January 1983 through February 1984.

Only 6.5% of all trials with the mount-only stimulus were successful in attracting birds. Tape-only and mount-and-tape stimuli were equally effective in attracting birds, but …

Tidewater Virginia: A Case Study In Health Planning, Maria Justice Moore Griffin

School of Public Service Theses & Dissertations

Leigh Memorial Hospital, a small private community care hospital merged with Norfolk General Hospital in 1972 to form an innovative health care corporation in Tidewater Virginia. By deciding to merge and alter its organizational identity, the Leigh Memorial Hospital leadership reversed a previous decision to relocate to the downtown Norfolk Medical Center complex, choosing instead to move to within a few yards of the neighboring city of Virginia Beach. Those two decisions and the story behind them are part of a complex, highly interdependent series of decisions which altered the health care delivery system in Tidewater Virginia.

This study is …

Activity Levels Of Arboreal Rodents Peromysus And Ochrotomys Evaluated With Nest Cans In Seasonally Flooded Forests, John W. Walke

Biological Sciences Theses & Dissertations

The diversity and density of small mammals in the Dismal Swamp are believed to be small. To test this, four 1.96 ha grids were established and operated in the Dismal Swamp National Wildlife Refuge, from September 1981 to November 1982. Number 10 metal cans covered with plastic lids were placed as nest boxes at 0.5 to 1.5 m height on trees. A 2.5 cm hole allowed access by arboreal rodents, to each nest can. The activity level of the two arboreal rodents, Peromyscus leucopus and Ochrotomys nuttalli, was evaluated by observing types of activity ranging from presence of mice to …

Germination And Host Range Of Branched Broomrape (Orobanche Ramosa) From Texas, Robert D. Coffin

Biological Sciences Theses & Dissertations

The effect of temperature on the germination of Orobanche ramosa L., branched broomrape, was investigated by dividing the physiological stages leading to germination into discrete events: pretreatment, a period when the seed becomes receptive to stimulant, and posttreatment, when stimulant application (GR-24) induces germination. Seed was pretreated and posttreated at 16 different temperature combinations. Optimal pretreatment was at 15°C and 18°C, maximum posttreatment at 18°C. Highest germination was obtained by pretreating and posttreating seed at 18°C, lowest at 24°C. The effect of different pretreatment regimes was tested. Seeds were pretreated over moist filter paper and in soil for Oto …

I.G. Farben's Petro-Chemical Plant And Concentration Camp At Auschwitz, Robert Simon Yavner

History Theses & Dissertations

This study examines the history of the petrochemical plant and concentration camp run by I.G. Farbenindustrie (the dominant German chemical company during World War II) at Auschwitz to decide upon the degree of Farben’s involvement with Hitler and the Holocaust. The study traces the construction of the plant to determine Farben's participation at Auschwitz. The main sources consulted were the transcripts of the postwar Farben trial at Nuremberg along with eyewitness accounts of members of the prosecution staff. Based on the court's verdict, one might conclude that I.G. Farben operated in a state of coercion during the war and could …