Sease, Anthony Mark

My wound is geography. It is also my anchorage, my port of call. -Pat Conroy<p>Existential contents have their source in the landscape. -Willy Hellpach<p>The preceding statements each reflect the significance of the landscape to ones existential being. The first embodies the veracity of the latter in its specificity of place, the tidal marshes and sea islands of the Carolinas.<p>How do we come to know a place? What is the significance of ones participato...

Muthanna, Chittiappa

An 8 blade, 7 passage linear compressor cascade with tip leakage was built. The flowfield downstream of the cascade was measured using four sensor hot-wire anemometers, from which the mean velocity field , the turbulence stress field and velocity spectra were obtained. Oil flow visualizations were done on the endwall underneath the blade row. Also studied were the effects of tip gap height, and blade boundary layer trip variations. The results revealed the presence of two distinct vortical struc...

Wenger, Christian W.

Simultaneous two-point three-component four-sensor hot-wire velocity measurements taken in three flows of aeroacoustic interest are here analyzed. The analyses provide information on the turbulence structure of the flows as it would be encountered by hypothetical noise producing blades passing through the flows. Two-point measurements taken in the first flow, a lifting wake from a rectangular NACA 0012 half wing, are used to calculate space-time correlation functions and pointwise wave number fr...

Maillard, Vincent M.

During the water quality and sludge characterization phase, average effluent quality over the course of a day was not found to be impaired during a 7-month sampling and monitoring study at the three trout farms. However, effluent quality was found to change significantly during times of high farm activity (i.e. feeding, harvesting, cleaning, etc.). Normalized Total Suspended Solids (TSS) concentrations were found to be as high as 115 mg/l during harvesting and 63 mg/l during feeding. Solids char...

Naghshineh-Pour, Amir H.

A significant improvement can be achieved in the performance of transonic transport aircraft using Multidisciplinary Design Optimization (MDO) by implementing truss-braced wing concepts in combination with other advanced technologies and novel design innovations. A considerable reduction in drag can be obtained by using a high aspect ratio wing with thin airfoil sections and tip-mounted engines. However, such wing structures could suffer from a significant weight penalty. Thus, the use of an ext...

West, Lee

Effects of fungi and overstory composition on tree seedling survival and growth were investigated in closed canopy upland forests in the coastal plain of South Carolina. Seedlings of Quercus alba, Cornus florida and Pinus taeda were planted in the understory of two forest types -naturally regenerated hardwood and planted pine. Fungal species composition and biomass were experimentally manipulated with a treatment of the fungicide captan.In contrast with other studies conducted in different syste...

Koechlein, David Jacob

Abstract: Following active growth, the aquatic gram-negative rod Prolinoborus fasciculus (Aquaspirillum fasciculus) exhibited a mass conversion from its culturable rod form to a nonculturable coccoid form. Chloramphenicol did not prevent the conversion. Attempts to obtain variants that would not convert to the coccoid form were unsuccessful. Although the coccoid form fluoresced with acridine orange, agarose gel electrophoresis revealed extensive ribosomal RNA degradation. Poly-ß-hydroxy...

Stivason, Charles T.

This research tests the ability of artificial learning methodologies to map market returns better than logistic regression. The learning methodologies used are neural networks and dual-layered genetic algorithms. These methodologies are used to develop a trading strategy to generate excess returns. The excess returns are compared to test the trading strategy s effectiveness. Market-adjusted and size-adjusted excess returns are calculated.Using a trading strategy based approach the logistic regre...

Nair, Arthur William

iiINVESTIGATION OF THE EFFECTS OF SEQUENTIALANAEROBIC, ANOXIC AND AEROBIC ZONES ON THEDISSOLVED OXYGEN TRANSFER PARAMETERS IN ABIOLOGICAL NUTRIENT REMOVAL PILOT PLANTbyArthur William NairC. W. Randall, ChairmanEnvironmental Engineering(ABSTRACT)Bench and pilot scale determinations of the volumetric oxygen transfer coefficient, K<sub>L</sub>a,were performed on an improved A<sup>2</sup>/O biological nutrient removal (BNR) pilot plant.Effluent...

Garcia, Albert

The TOPEX/POSEIDON Project is a joint U.S. and French mission to develop and operate an Earth orbiting satellite capable of making accurate measurements of the mean sea level in a way that allows the study of ocean dynamics. The understanding of ocean dynamics is very important in order to study events such as El Nino. Soon after the launch of the TOPEX satellite, some unusually high, but localized, values of the ocean s radar cross section, sigma-0, were observed by scientists at the NASA Godda...

Ganesan, Vikram

This thesis describes a multidisciplinary design optimization approach to containership design. The method employs widely accepted regression equations for computing resistance, weights, building costs and operating costs. The current regulations governing freeboard and the Coast Guard wind heel criterion are included.The measures of merit used are the required freight rate and the return on investment. The system is flexible enough to allow changes in trade routes, shipyard and port parameters,...

Boyd, Jr., David Douglas

A new unsteady rotor/fuselage interactional aerodynamics modelhas been developed. This model loosely couples a GeneralizedDynamic Wake Theory (GDWT) to a Navier-Stokes solutionprocedure. This coupling is achieved using a newly developedunsteady pressure jump boundary condition in the Navier-Stokesmodel. The new unsteady pressure jump boundary condition models eachrotor blade as a moving pressure jump which travels around the rotor azimuthand is applied between two adjacent planes in a cylindrica...

Zoeckler, Jeff Radcliffe

In this study, the biodegradation potential of MTBE in uncontaminated and previously contaminated aquifer sediments under aerobic conditions was investigated. Laboratory microcosms were constructed using aquifer samples collected from three different areas of a shallow gasoline-contaminated aquifer in eastern Fairfax Co., Va in the Atlantic Coastal Plain province. Uncontaminated aquifer samples were collected upgradient of the plume, and contaminated aquifer samples were collected in the source ...

Bush, Andrew Milton

The morphologic variability of a fossil assemblage is of interest in many paleontological studies. However, many fossil assemblages are time-averaged; that is, many generations of non-contemporaneous organisms are mixed into the same fossil bed. Assemblages of robust mollusk shells deposited in nearshore marine environments are often time-averaged over 100s to 1000s of years. Mixing many generations of a taxon can increase measured morphologic variability over that of a single generation if morp...

Scott, Michael Leon

Many problems are involved with intspecting and evaluating the condition ofbridges in the United States. Concrete bridge deck inspection and evaluationpresents one of the largest problems. The deterioration of these concretedecks progresses more rapidly than any other bridge component, which leads toearly concrete deck replacements that must be done before the bridgesuperstructure needs to be replaced. The primary cause of deterioration inthese concrete bridge decks is corrosion-induced concrete...

Scalera, Kevin R.

A comparison of two control allocation methods is performed utilizing the F-15 ACTIVE research vehicle. The control allocator currently implemented on the aircraft is replaced in the simulation with a control allocator that accounts for both control effector positions and rates. Validation of the performance of this Moment Rate Allocation scheme through real-time piloted simulations is desired for an aircraft with a high fidelity control law and a larger control effector suite.A more computation...

Gilmore, Kevin Robert

A pilot-scale, two-stage (carbon oxidation stage one, ammonia oxidation stage two) fixed film biological aerated filter (BAF) process was operated on-site at a domestic wastewater treatment plant. Over the study period, hydraulic loadings to the system were varied, generating a range of organic and ammonia loading conditions. Nitrification was monitored along the length of the filters by measuring chemical nitrogen species and activity levels of ammonia oxidizing bacteria (AOB). During the first...

Schmitz, Mark Harvey

(Abstract not completed yet)

Wang, Yu

A large-scale moving end-wall system has been designed and built at the Aerospace and Ocean Engineering Department of Virginia Tech. This system forms part of a low-speed linear compressor cascade wind tunnel, where it is used to simulate the effects of the relative motion between the blade tips and casing upon the flow. Detailed 4-sensor hot wire measurements were made at various locations downstream the cascade. The results are presented in term of mean flow field and turbulence flow field. In...

Farrell, Inez Hofner

Navigation tools can be used to direct the amount of learner control and interactivity available in a hypermedia hybrid CD-ROM environment. The purpose of this study was to ascertain if varying the amount of learner control and interactivity through the used of navigation tools would influence the achievement and attitude of learners. The design of the study was a quasi-experimental study with random assignment of three ability levels of students to three navigation tool treatment groups. A 3 (n...

Webler, James Edward

The purpose of this study is to further evaluate the performance of the 5/16 in. diameter Elco Grade 8 standoff screw as a mechanical shear connector in composite joists. Standoff screws are being investigated as viable an alternative to welded shear studs in short span composite joists. The data and results obtained from 59 pushout tests performed on the 5/16 in. diameter Elco Grade 8 standoff screw are presented. The test parameters investigated in this study include: standoff screw height, qu...

Limache, Alejandro Cesar

A mathematical model for the determination of the aerodynamicforces acting on an aircraft is presented.The mathematical model is based on the generalization of theidea of aerodynamicallysteady motions. One important use of these results is thedetermination of steady (time-invariant) aerodynamic forcesand moments. Such aerodynamic forces can be determined usingcomputer simulation by determining numerically the associatedsteady flows around the aircraft when it is moving along suchgeneralized stea...

Hanlon, Shane David

Recent efforts to restore depressed or extirpated populations of freshwater mussels have focused on artificial propagation as an effective and practical conservation strategy. Although artificially cultured juveniles have been produced and released to the wild, no study has investigated the best time of year or the best developmental stage to release these juveniles. Several experiments were conducted to gain knowledge of appropriate culture and release techniques. Juvenile wavyrayed lampmussels...

Bonds, Charles Craig

Gizzard shad were illegally introduced to Claytor Lake in the late 1980s and soon established a thriving population. This study assessed 1) the degree to which gizzard shad were utilized by piscivores (pelagic - striped bass Morone saxatilis, hybrid striped bass M. chrysops x M. saxatilis, and walleye Stizostedion vitreum, and three littoral black basses Micropterus spp.), 2) the availability of gizzard shad as potential prey as determined from age and growth analysis, and 3) the performance (gr...

Adams, Stephanie E.

Despite widespread alcohol use by college students, the majority of them appear capable of controlling their drinking. The present study sought to develop a measure assessing college students use of self-regulatory strategies in an effort to control their drinking. Three hundred and ten undergraduates completed questionnaires assessing a variety of alcohol-related behaviors and beliefs, as well as academic performance and strategy use. A fifty-item Drinking Self-Regulation Questionnaire (DSRQ) w...

Kantrovich, Adam Joseph

The review of the literature reveals the historical nature of Vocational Education programs and how they relate to the importance of Virginia Tech s two-year post-secondary Agricultural Technology Program. The literature review also provides a historical review of information regarding Virginia Tech s Agricultural Technology program, brief histories of other post-secondary land-grant two-year agricultural programs, vocational education philosophers, and two-year program evaluations.<p&amp...

Dalton, M. Nell

The effect of dietary fats on reproductive performance, egg quality, fatty acid composition of tissues and egg yolk, and prostaglandin levels in embryonic tissues in Japanese quail (Coturnix, coturnix japonica) were evaluated. The addition of 5.0% chicken fat (CHX), hydrogenated soybean oil (HSBO), menhaden fish oil (MENH) or soybean oil (SBO) to the maternal and paternal diet altered tissue and yolk composition of the hens and tissue composition of the males to reflect the dietary source. Compa...

Mujagic, Ubejd

The objective of the research reported herein is to present a comprehensive evaluation of all available experimental data from push-out tests utilizing the ELCO Grade 8 standoff screws. The goal is to develop a strength prediction equation and determine reliability parameters compatible with the Load Factor Resistance Design (LRFD) procedure that would allow the use of this shear connector in design of composite floor systems.The study considers results from push-out tests using this type of scr...

Tuohy, Brent Travis

Work has been done to develop the computer laboratory portion of a course in biodynamic modeling, with particular emphasis towards applications in forensic engineering. Three course modules have been developed which explore the whiplash injury mechanism, pilot ejection and windblast, and gait analysis. These case studies make use of software entitled MADYMO (MAthematical DYnamic MOdeling). Each case study provides the scene, outcome, details, and instructions for setup of the biodynamic model. A...

Kim, Myung-Hyun

A robust nonlinear observer, utilizing the sliding mode concept, is developed for the dynamic positioning of ships. The observer provides the estimates of linear velocities of the ship and bias from the slowly varying environmental loads. It also filters out wave frequency motion to avoid wear of actuators and excessive fuel consumption. Especially, the observer structure with a saturation function makes the proposed observer robust against neglected nonlinearties, disturbances and uncertainties...

Suleiman, Baha M.

Accurate ship-motion prediction is important because it is directly related tothe design, control, and economic operation of ships.Many methods are available for studying and predicting ship motions,including time-domain, strip-theory, and system-identification-based predictions.Time-domain and strip-theory predictions suffer from several physical and computational limitations.In this work, we use system-identification techniques to predict ship motions.We establish an identification methodology...

Iglesias, Sergio

The classic minimum induced drag spanload is not necessarily the best choice for an aircraft. For a single aircraft configuration, variations from the elliptic, minimum drag optimum load distribution can produce wing weight savings that result in airplane performance benefits. For a group of aircraft flying in formation, non-elliptic lift distributions can give high induced drag reductions both for the formation and for each airplane.<p>For single aircraft, a discrete vortex method...

Clements, Joshua Ryan

Active Magnetic Bearings (AMB) are a relatively recent innovation in bearing technology. Unlike conventional bearings, which rely on mechanical forces originating from fluid films or physical contact to support bearing loads, AMB systems utilize magnetic fields to levitate and support a shaft in an air-gap within the bearing stator. This design has many benefits over conventional bearings. The potential capabilities that AMB systems offer are allowing this new technology to be considered for use...

Hu, Guangchu

An accurate and efficient numerical method for Compressible Vorticity Confinement (CVC) was developed. The methodology follows from Steinhoffs vorticity confinement approach that was developed for incompressible flows. In this research, the extension of this approach to compressible flows has been developed by adding a vorticity confinement term as a body force into the governing compressible flow equations. This vorticity confinement term tends to cancel the numerical dissipative errors inheren...

Wishart, DeBonne Natalie

Hydrogeology and Simulated Water Budget of the Rio Cobre and Rio Minho-Milk River Basins, Jamaica, West IndiesbyDeBonne N. WishartT.J. Burbey, ChairmanDepartment of Geological Sciences, Virginia Polytechnic Institute & State University Blacksburg, Virginia 24061-0420(ABSTRACT)An investigation was undertaken to better understand the hydrogeologic framework of the Rio Cobre and Rio Minho-Milk river basins, Jamaica, West Indies. A quasi three-dimensional finite-difference groundwater flow m...

Watkins, James R.

House Bill 38 will allocate up to $13 million per year in state sales tax revenue to the Virginia Department of Game and Inland Fisheries (VDGIF) beginning in Fiscal Year 2001. To plan for this major budget enhancement, the VDGIF asked us (in cooperation with Responsive Management and Dr. Brett Wright) to identify the agency programs and functions that VDGIF employees gave high priority to for the allocation of additional resources, and to compare these priorities with those of the agencys exter...

Ni, Lingli

Unmanned Underwater Vehicles (UUVs) are widely used in commercial, scientific, and military missions for various purposes. What makes this technology challenging is the increasing mission duration and unknown environment. It is necessary to embed fault-tolerant control paradigms into UUVs to increase the reliability of the vehicles and enable them to execute and finalize complex missions. Specifically, fault-tolerant control (FTC) comprises fault detection, identification, and control reconfigur...

Wang, Hongwei

Boundary layer characteristics at the trailing edge of a tiltrotor blade model were measured using a flattened pitot probe and a single hot wire. The blade was mounted in Virginia Tech Stability Wind tunnel stationary on a turntable on the wind tunnels upper wall with the tip pointing down. The measurement point was located at 1 mm behind the trailing edge to make it possible to measure the flow near the blade surface and measure the boundary layer on both sides of the trailing edge in a same ru...

Sandfry, Ralph Anthony

We investigate the relative equilibria of a gyrostat with aspring-mass-dashpot damper to gain new insights into the dynamicsof spin-stabilized satellites. The equations of motion aredeveloped using a Newton-Euler approach, resulting in equations interms of system momenta and damper variables. Linear and nonlinearstability methods produce stability conditions for simple spinsabout the nominal principal axes. We use analytical and numericalmethods to explore system equilibria, including the bifurc...

Karlgaard, Christopher David

This thesis presents an approximate solution of second orderrelative motion equations. The equations of motion for a Keplerianorbit in spherical coordinates are expanded in Taylor series formusing reference conditions consistent with that of a circularorbit. Only terms that are linear or quadratic in state variablesare kept in the expansion. A perturbation method is employed toobtain an approximate solution of the resulting nonlineardifferential equations. This new solution is compared with thep...

HOSDER, SERHAT

Steady and unsteady flow over a generic Suboff submarine model is studied. The skin-friction magnitudes are measured by using hot-film sensors each connected to a constant temperature anemometer. The local minima in the skin-friction magnitudes are used to obtain the separation locations. Steady static pressure measurements on the model surface are performed at 10�X and 20�X angles of attack. Steady and unsteady results are presented for two model configurations: barebody and sail-on-side case. ...

Culver, Judd Niles

Evaluation of Tom Fertility as Affected by Dietary Fatty Acid CompositionbyJudd N. CulverD. M. Denbow, ChairmanAnimal and Poultry SciencesABSTRACT The objective of two studies was to manipulate the essential fatty acid content of turkey semen by enhancing the dietary levels of either n-3 polyunsaturated fatty acids (PUFA) or n-6 PUFA and determine the effect on fertility. In 1999 (Trial 1), and again in 2000 (Trial 2), Large White tom turkeys, 37 weeks of age, were fed one of three diets substit...

Kim, Hongman

Errors of computational simulations in design ofa high-speed civil transport (HSCT) are investigated.First, discretization error from a supersonic panel code,WINGDES, is considered. Second, convergence error froma structural optimization procedure using GENESIS isconsidered along with the Rosenbrock test problem.A grid converge study is performed to estimatethe order of the discretization error in the liftcoefficient (CL) of the HSCT calculated from WINGDES.A response surface (RS) model using se...

Postlethwait, Niel Holland

A cation exchange method (Chelex 100) that distinguishes weakly bound and strongly bound copper was investigated for its ability to measure bioavailable copper in estuarine waters. Copper bound to the Chelex 100 resin was operationally defined as bioavailable copper. Varying initial copper concentration from 195 to 495 ug/L at a constant 12.5 mg/L natural organic matter (NOM) did not affect percent bioavailability. There were also no noticeable effects when varying total Cu concentration in the ...

Mish, Patrick F.

Detailed surface pressure measurements have been made on a NACA 0015 immersed in two grid generated homogenous flows at Re = 1.17 x 10^6 for a = 0�X, 4�X, 8�X, 12�X, 16�X, and 20�X. The goal of this measurement was to reveal and highlight mean loading and turbulence scale effects on surface pressure fluctuations resulting from turbulence/airfoil interaction. Also, measurements are compared with the theory of Amiet (1976a,b). The surface pressure response shows a dependance on angle of attack, th...

Sulaeman, Erwin

Recent investigations of a strut-braced wing (SBW) aircraft show that, at high positive load factors, a large tensile force in the strut leads to a considerable compressive axial force in the inner wing, resulting in a reduced bending stiffness and even buckling of the wing. Studying the influence of this compressive force on the structural response of SBW is thus of paramount importance in the early stage of SBW design.The purpose of the this research is to investigate the effect of compressive...

Bandorawalla, Tozer Jamshed

With the increasing use of composite materials for diverse applications ranging from civil infrastructure to offshore oil exploration, the durability of these materials is an important issue. Practical and accurate models for lifetime will enable engineers to push the boundaries of design and make the most efficient use of composite materials, while at the same time maintaining the utmost standards of safety. The work described in this dissertation is an effort to predict the strength and ruptur...

Conley, Valerie Martin

Faculty members are influenced by a complex set of factors when making decisions about when to retire. These factors generally include both financial and non-financial characteristics. This study was designed to examine the non-financial factors related to the retirement process for selected faculty groups. Key components of the design included selecting faculty groups for analysis and identifying the non-financial factors related to the retirement process. Two faculty groups were selected: (a) ...

Chamberlain, James Luther

Many products are harvested from the forests of the United States in addition to timber. These non-timber forest products (NTFPs) are plants, parts of plants, or fungi that are harvested from within and on the edges of natural, disturbed or managed forests. Often, NTFPs are harvested from public forests for the socio-economic benefit they provide to rural collectors.Social science and market research methods were used to examine the extent that NTFPs are addressed in national forest management p...

Krause, Colin William

The SNTEMP (U.S. Fish and Wildlife Service), QUAL2E (U.S. Environmental Protection Agency), and RQUAL (Tennessee Valley Authority) stream temperature prediction models were evaluated. All models had high predictive ability with the majority of predictions, >80% for Back Creek (Roanoke County, VA) and >90% for the Smith River tailwater (SRT) (Patrick County, VA), within 3�XC of the measured water temperature. Sensitivity of model input parameters was found to differ between model, s...