AL-Aqrabawi, Mohammad Saleh

Maintaining large-scale legacy applications has been a major challenge for software producers. As the application evolves and gets more complicated, it becomes harder to understand, debug, or modify the code. Moreover, as new members are joining the development team, and others are leaving, the need for a well-documented code arises. Good documentation necessitates the visualization of the code in an easy to understand manner. The Unified Modeling Language (UML), an Object Management Groups (OMG...

Temeles, Anthony B.

Two 7" deep FRP deck panels were manufactured and tested in a controlled service environment. The deck panels were 15 by 5 in plan, and were composed of ten 15 long, 6" by 6" by 3/8" standard pultruded FRP tubes. The tubes were sandwiched between two 3/8" thick standard pultruded FRP plates. The material constituents of the FRP were E-glass fibers in a polyester matrix. When subjected to two strength tests, the first deck panel exhibited a safety factor with respect to l...

Tuckey, Donna M.

1-substituted 1,2,4-triazoles form a class of agricultural chemicals known as sterol-inhibiting fungicides (SIFs). These fungicides function through the inhibition of sterol synthesis, which ultimately affects cell membrane fluidity and permeability. Of the two main types of sterols in plants, free sterols (FSs) are thought to be incorporated into membranes while conjugated sterols such as steryl esters (SEs), hypothetically, regulate homeostasis by inserting or removing FSs from cell membranes ...

Bowden, Brent Christopher

Oxytetracycline (OTC) is one of two antibiotics currently available and approved bythe U.S. Food and Drug Administration for use as a chemotherapeutic agent in food fishand is widely used in the aquaculture industry. Previous pharmacokinetic studies of OTChave been conducted in cold water and warm water species of fish. However, nopharmacokinetic studies have been conducted on a cool water species such as yellowperch (Perca flavescens). The yellow perch is a cool water game and commercial specie...

Lee, Wey-Jen

An analytical investigation was conducted to study the behavior of a bottom flange bearing beam-to girder connection subjected to patch loading. This connection would be useful with deep deck (thickness greater than 3 in.) composite slabs as well as with commonly used deck where floor-to-floor height needs to be minimized. Five girder specimens were loaded until yielding during the initial phase of the research. The analysis section consists of the yield line theory and finite element study that...

Eisenmann, Matthew Donnel

Hindered-bed separators have been used in several different mineral processing fields for many years. Recent improvements in designs have led to the development of the CrossFlow separator. This new design employs a tangential feed system that has shown promise in several applications. This paper investigates the use of this relatively new technology to upgrade heavy mineral concentrates using Florida type ores. The intended use of this separatory device in this particular application is the remo...

Orndorff, Zenah Wilson

Road construction through sulfidic materials in Virginia has resulted in localized acid rock drainage (ARD) that threatens water quality, fill stability, integrity of building materials, and vegetation management. The objectives of this study were: i) to develop a state-wide sulfide hazard rating map based on characterization of the geologic formations associated with acid roadcuts, ii) to estimate depth to sulfidic sediments in the Coastal Plain based on landscape relationships, and iii) to eva...

Dritsas, Lawrence Stratton

My thesis describes the praxis of geographical exploration in the mid-nineteenth century through the activities of members of the Royal Geographical Society of London (RGS). I focus on the First East African Expedition (1856-1859), which was led by Richard F. Burton. Geographical exploration was intended to provide data that would allow geographers in Britain to construct an accurate description of East Africa, with emphasis on the rivers and lakes that may contribute to the waters of the Nile a...

Wood, William Alfred

A multi-dimensional upwind fluctuation splitting scheme is developed andimplemented for two-dimensional and axisymmetric formulations of theNavier-Stokes equations on unstructured meshes.Key features of the scheme are the compact stencil, full upwinding, andnon-linear discretization which allow for second-order accuracy withenforced positivity.Throughout, the fluctuation splitting scheme is compared to a currentstate-of-the-art finite volume approach, a second-order, dual meshupwind flux differe...

Nelson, Mark David

A comparison of two methods to deal with allocating controls for unattainable moments in an aircraft was performed using a testbed airframe that resembled an F/A-18 with a large control effector suite. The method of preserving the desired moment direction to deal with unattainable moments is currently used in a specific control allocator. A new method of prioritizing the pitch axis is compared to the moment-direction preservation. Realtime piloted simulations are completed to evaluate the charac...

Brazil, Brian Ligar

The ability of a self-contained denitrification system, using fermentation products from waste fish solids, to maintain reliable performance was studied. Denitrification performance was described kinetically and stoichiometrically under different initial nitrate-nitrogen and soluble organic carbon to nitrate-nitrogen ratios. Characterization of soluble organic carbon (measured as soluble chemical oxygen demand, sCOD) indicated that volatile fatty acids (VFA) were generated during the fermentatio...

Riley, Jr., Joseph Michael

To test factors limiting regeneration of large-seeded hardwoods in the Upper Coastal Plain of South Carolina, we planted one-year old bare root Quercus alba L. and Cornus florida L. seedlings in pine plantation understories and adjacent clearcuts. We hypothesized that soil moisture, light, and leaf and stem herbivory would have relatively strong effects on growth and survival during the first two years after planting. Next to each seedling, we measured five abiotic factors (soil carbon and moist...

Guo, Dali

There has been an increased interest in characterizing and interpreting ecological heterogeneity over space and time in the past two decades. This is mainly due to the renewed recognition of the significance of heterogeneity in ecological theories. However, studies that have combined both spatial and temporal aspects of heterogeneity have been rare. A unified approach to define and quantify heterogeneity has also been lacking. Designed to overcome these problems, this study was conducted in a 40...

Natarajan, Anand

In this dissertation, neural networks are designed to effectively model static non-linear aeroelastic problems in adaptive structures and linear dynamic aeroelastic systems with time varying stiffness. The use of adaptive materials in aircraft wings allows for the change of the contour or the configuration of a wing (morphing) in flight. The use of smart materials, to accomplish these deformations, can imply that the stiffness of the wing with a morphing contour changes as the contour changes. F...

McGehee, Nancy Gard

This study develops and tests a theoretical modeldrawing on social psychological andresource-mobilization perspectives of social movementtheory to explain changes in social movement participationand support for activism among Earthwatch Expeditionvolunteers. The social psychological perspective ofsocial movements recognizes the role of self-efficacyand consciousness-raising for the participation in andsuccess of social movement organizations. The resourcemobilization perspective of social moveme...

Pettersson, Henrik Bengt

Simulation, whether in-flight or ground-based, is an invaluable tool for testing andevaluating aircraft. Classically, a simulation model is specific to a single particular airframe,only able to model those flying characteristics. Vast information can be gained from asimulation that is able to model a wide range of aircraft, through a comparison of theperformance of these aircraft.Such a variable stability simulation model was created based on 46 stability parame-ters,including natural frequencie...

Intaratep, Nanyaporn

The inboard-winglet concept was examined for its flow characteristics by testing for pressure coefficients over the wing and winglet surface in the Virginia Tech Stability Wind Tunnel over a range of freestream velocity and angle of attack. The results were analytically applied to calculate aircraft performance of a roadable aircraft, Pegasus II, which used the inboard-winglet concept in its design. The results proved that this concept has the potential to increase a wing lift coefficient at the...

White, Dave D.

The purposes of this study were to examine 1) understandings of science expressed in formal salmon recovery policy discourse; 2) rhetorical practices employed to justify or undermine claims about salmon policy 3); and patterns of understandings of science and associated rhetorical practices between social categories of actors. This research contributes to scholarship in public understanding of science, discourse studies, and natural resource policy.A constructivist discourse analysis was conduct...

Beck, Roger Ezekiel

Methods for allocating redundant controls for systems with four or more objectives are studied. Previous research into aircraft control allocation has focused on allocating control effectors to provide commands for three rotational degrees of freedom. Redundant control systems have the capability to allocate commands for a larger number of objectives. For aircraft, direct force commands can be applied in addition to moment commands.<p>When controls are limited, constraints must be ...

Schmidt, John Michael

Litter decomposition is a poorly understood function of constructed and natural forested wetlands. This study compared rates of litter mass loss, changes in litter morphology, and associated macroinvertebrate populations in constructed and natural non-tidal wetlands. Two sets of wetlands (constructed vs. natural) were studied in eastern Virginia; a 9 year-old riparian set near Fort Lee, (FL), and a 2 year-old wet flat set in Charles City County, (CC). Mixed deciduous forest litter collected from...

Pope, Jason Philip

Measurement and analysis of aquifer-system compaction have been used tocharacterize aquifer and confining unit properties when other techniques such as flowmodeling have been ineffective at adequately quantifying storage properties or matchinghistorical water levels in environments experiencing land subsidence. In the southeasternCoastal Plain of Virginia, high-sensitivity borehole pipe extensometers were used tomeasure 24.2 mm of total compaction at Franklin from 1979 to 1995 (an average of 1.5...

Nassar, Adil J.

AbstractInvestigation of Transfer Length, Development Length, Flexural Strength and Prestress Loss Trend in Fully Bonded High Performance Lightweight Prestressed T-BeamsAdil J. NassarVirginia Polytechnic Institute andState University, 2002Supervisor: Dr. Thomas E. CousinsEncouraged by the performance of high performance normal weight composite girders, Virginia Department of Transportation has sought to exploit the use of high strength lightweight composite concrete (HSLWC) girders to achieve ec...

Zhu, Qinwei

The high demand for building digital libraries by non-experts requires a simplified modeling process and rapid generation of digital libraries. To enable rapid generation, digital libraries should be modeled with descriptive languages. A visual modeling tool would be helpful to non-experts so they may model a digital library without knowing the theoretical foundations and the syntactical details of the descriptive language.In this thesis, we describe the design and implementation of a domain-spe...

Anderson, Cheryl A.

Residential deck and balcony failures are preventable if the decks and balconies are maintained and inspected regularly. Inspection of in-service decks or balconies is not common and often is unregulated or building codes do not appear to be widely enforced. With every failure, the need for a comprehensive inspection manual for residential wood decks and balconies becomes more apparent.Research was conducted on inspection techniques, common deck and balcony construction methods, maintenance issu...

Alam, Fakhrul

The capacity of a cellular system is limited by two different phenomena, namely multipath fading and multiple access interference (MAI). A Two Dimensional (2-D) receiver combats both of these by processing the signal both in the spatial and temporal domain. An ideal 2-D receiver would perform joint space-time processing, but at the price of high computational complexity. In this dissertation we investigate computationally simpler technique termed as a Beamformer-Rake. In a Beamformer-Rake, the o...

Goyal, Vinay K

With the traditional fracture mechanics approaches, an initial crack and self-similar progressionof cracks are assumed. In this treatise, theoretical and numerical tools are developedto mathematically describe non-self-similar progression of cracks without specifying an initialcrack. A cohesive-decohesive zone model, similar to the cohesive zone model known in fracturemechanics as Dugdale-Barenblatt model, is adopted to represent the degradation of thematerial ahead of the crack tip. This model ...

Zhou, Aixi

This research investigates two principal characteristics that are of primary importance in Fiber Reinforced Polymer (FRP) bridge deck applications: STIFFNESS and STRENGTH. The research was undertaken by investigating the stiffness and strength characteristics of the multi-cellular FRP bridge deck systems consisting of pultruded FRP shapes.A systematic analysis procedure was developed for the stiffness analysis of multi-cellular FRP deck systems. This procedure uses the Method of Elastic Equivale...

Mohammad, Maruf H.

Blind Acquisition of Short Burst with Per-Survivor Processing (PSP)Maruf Mohammad(Abstract)This thesis investigates the use of Maximum Likelihood Sequence Estimation (MLSE) in the presence of unknown channel parameters. MLSE is a fundamental problem that is closely related to many modern research areas like Space-Time Coding, Overloaded Array Processing and Multi-User Detection. Per-Survivor Processing (PSP) is a technique for approximating MLSE for unknown channels by embedding channel estimati...

Beck, Kevin Moran

Feeding selectivity by the rainbow mussel (Villosa iris) was examined for three age groups; 2-3 days old, 50-53 days old, and 3-6 years old. The mussels were fed an algal diet consisting of Scenedesmus quadricauda (22.3 - 44.5 Ým), Nannochloropsis oculata (2.8 ¡V 8.1 Ým), and Selenastrum capricornutum (3.6 ¡V 8.5 Ým) in equal cell densities. The change in relative abundance of each algal species within feeding chambers over a 5 hr feeding trial was us...

SANG, ALEXANDER KIPKOSGEI

<p>A non-intrusive direct-measuring skin friction device with a rubber RTV sheet over the surface of the floating head, gap and housing was developed for application in 3D, unsteady, transonic flight conditions. Design conditions required optimum gage performance at altitudes ranging from 15,000 to 45,000 feet, Mach numbers ranging from 0.6 to 0.99 resulting in shear values of 0.3 to 1.5 psf. under vibration conditions up to 8.0 grms over a 15 - 2,000 Hz frequency range. The gage c...

Treakle, Thomas W. III

Time-domain simulations were performed to investigate the influence ofpassive and active anti-roll tanks and moving weights on ship motions. Apoint mass moving across the ship was used to model the non-linear effectsof the tank systems in various computer simulation environments. PIDcontrol of the mass position was used for the active tank (pump) systemsand a vibration absorber was used for the passive tank systems. Asingle-degree-of-freedom non-linear code was developed to investigate theinflue...

Farahani, Gohar Omidvar

This research explored the existence and importance of interaction in online courses as perceived by online learners and instructors. The study was based on data from online students and instructors in the fall 2002 semester at Mid-Atlantic Community College(1). Two web-based surveys were used to collect data. Eighty-eight of 267 online students completed the survey, for a response rate of 33%. The study was based on constructivist theory which suggested that students learn by actively participa...

Ghosh, Biswarup

In this thesis improved expressions for elastic local plate buckling and overall panel buckling of uniaxially compressed T-stiffened panels are developed and validated with 55 ABAQUS eigenvalue buckling analyses of a wide range of typical panel geometries. These two expressions are equated to derive a new expression for the rigidity ratio (EIx/Db)CO that uniquely identifies ¡�Xcrossover¡�� panels ¨C those for which local and overall buckling stresses are the same. The ...

Smith, Ryan Kennerly

I investigated streambed stability in spawning microhabitats of warmwater fishes in the upper Roanoke River, Virginia. Spawning microhabitats used by four reproductive guilds (egg-clusterers, mound-builders, egg-buriers, and pit-builders) were identified and ranges of 15 microhabitat variables used by each guild were compared to available microhabitat conditions to investigate habitat selection. Habitat usage by egg-clusterers was most characterized by selection for spawning rocks in the cobble ...

Mierzwicki, Timothy Stephen

The naval ship concept design process often embraces novel concepts and technologies that carry with them an inherent risk of failure simply because their application is the first of its kind. Failure is recognized by gaps between actual and required measures of performance, exceeded budgets, and late deliveries. These risks can be defined and quantified as the product of the probability of an occurrence of failure and a measure of the consequence of that failure. Since the objective of engineer...

Cruz, Juan Ramón

An investigation was conducted to assess the usefulness of anti-optimization in the process of validating of aerodynamic codes. Anti-optimization is defined here as the intentional search for regions where the computational and experimental results disagree. Maximizing such disagreements can be a useful tool in uncovering errors and/or weaknesses in both analyses and experiments.The codes chosen for this investigation were an airfoil code and a lifting line code used together as an analysis to p...

Look, Mary V.

This dissertation examined how complexity theory might offer insight into the behavior of a population of large-scale networked organizational groups. Academic medical centers (AMCs), a large-scale social and policy system that plays a key role in the education of physicians, the conduct of research, and the provision of specialized clinical care, were chosen as an example to demonstrate the enhanced understanding that can be obtained from the application of complexity theory. Graphical and nonl...

Lee, Moira Elizabeth

This study tests an aspect of the environmental theory of Peter Huber outlined in his book <i>Hard Green: Saving the Environment from the Environmentalists: A Conservative Manifesto</i> (1999). Huber s thesis is that wealth leads to environmental conservation in two ways: 1) that wealthy nations develop and implement technologies to maximize the efficiency of land use, and 2) that wealthy individuals pour their wealth into the conservation of nature. Using secondary d...

Ko, Yan-Yee Andy

The purpose of this study is to examine the multidisciplinary design optimization (MDO) of a distributed propulsion blended-wing-body (BWB) aircraft. The BWB is a hybrid shape resembling a flying wing, placing the payload in the inboard sections of the wing. The distributed propulsion concept involves replacing a small number of large engines with many smaller engines. The distributed propulsion concept considered here ducts part of the engine exhaust to exit out along the trailing edge of the w...

Palmer, George Caleb

Historically, the New River may have contained a genetically unique, river-spawning population of walleye (Stizostedion vitreum). Additionally, a number of genetically different walleye stocks have been stocked in Claytor Lake, Virginia. The increasing importance of the walleye fishery led to interest in clarifying key unknowns regarding the biology of the New River walleye stock. A radio telemetry study and genetic evaluation of present-day stocks led to identification of three spawning areas a...

Orr, Matthew William

This investigation examines a new concept in airliner configurations from an experimental aerodynamics point of view. The concept proposes mounting the fuselages at the tips of a low aspect ratio wing. The motivation for this configuration is to provide an increase in the number of passengers carried with no increase in span over conventional designs. An additional motivation is the change in the wake flow of the wing, due to the fuselages and vertical tails, which may reduce the effect of the t...

Nayfeh, Nader Ali

Cranes are increasingly used in transportation and construction. Increasing demand andfaster requirements necessitate better and more efficient controllers to guarantee fast turn-aroundtime and to meet safety requirements. Container cranes are used extensively inship-to-port and port-to-ship transfer operations.In this work, we will extend the recently developed delayed position feedback controllerto container cranes. In contrast with traditional work, which models a crane as a simplependulum co...

Skelton II, Claude Eugene

Attitude control laws that use control moment gyros (CMGs) and momentum wheels are derived with nonlinear techniques. The control laws command the CMGs to provide rapid angular acceleration andthe momentum wheels to reject tracking and initial condition errors. Numerical simulations of derived control laws are compared. A trend analysis is performed to examine the benefits ofthe derived controllers. We describe the design of a CMG built using commercial off-the-shelf (COTS) equipment. A mixed at...

Brooks, Matthew A.

BREAKPOINT CHLORINATION AS AN ALTERNATE MEANSOF AMMONIA/NITROGEN REMOVAL AT A WATER RECLAMATION PLANTby Matthew A. BrooksAdil N. Godrej, ChairmanEnvironmental Sciences and Engineering(ABSTRACT)Numerous wastewater treatment processes are currently available for nitrogen removal or ammonia conversion to nitrate. Those that are economically feasible rely mostly on microbiological processes, which are only effective when the microorganisms remain in a healthy state. If a biological process upset was...

Munshaw, Gregg C.

Winter injury of bermudagrass (Cynodon spp.) continues to be a problem across the transition zone. In an attempt to delay or induce winter dormancy while maintaining cold hardiness, applications of seaweed extract (SWE) (0.54 kg ha-1), ethephon (16 L ha-1), Fe (1 kg ha-1), and N (49 kg ha-1) took place every three weeks during the fall of 2001 and 2002. Cultivars examined included Riviera, Midiron, Princess, and Tifway. Tifway exhibited greatest fall color retention in both years of the study. E...

Bezuidenhout, Johannes Jurie

Effective gages to measure skin friction and heat transfer have been established over decades. One of the most important criteria in designing such a gage is the physical size of the gage to minimise the interference of the flow, as well as the mass of these devices. The combined measurement of skin friction and heat flux using one single gage on the other hand, present unique opportunities and with it, unique technical problems. <P> The objective of this study is therefore to deve...

Kim, Yong Yook

The objective of this work was to employ artificial neural networks (NN) to solve inverse problems in different engineering fields, overcoming various obstacles in applying NN to different problems and benefiting from the experience of solving different types of inverse problems. The inverse problems investigated are: 1) damage detection in structures, 2) detection of an anomaly in a light-diffusive medium, such as human tissue using optical imaging, 3) structural optimization of fiber optic sen...

LaGesse, Jenny Heather

ABSTRACT:Cores, quarry exposures, and exploratory wells in the Paleogene Albemarle Basin, North Carolina sample the transition between the southern carbonate and northern siliciclastic provinces of the eastern U.S. continental shelf succession. The study area includes the relatively positive Cape Fear Arch on the Onslow Block to the south, and the slowly subsiding (1.5 cm/ky) Albemarle Block to the north.The Paleogene supersequence set boundary is a hardground on Cretaceous shoreface/shallow-she...

Arnold, Matthew Scott

Microtubules are critically important cytoskeletal elements. Together with microtubule associated proteins (MAPs), they form the latticework on which eukaryotic life exists. Simply put, microtubules are polymers of tubulin heterodimers, which are composed of the globular proteins alpha and beta tubulin. In vivo, these monomers associate with one another to form heterodimers, which then polymerize to form microtubules.In mammals, microtubule polymerization is a temperature-dependent process with ...

Maria Ana Farinaccio

Este trabalho trata das Asclepiadoideae (Apocynaceae) do Parque Nacional da Serra da Canastra. O Parque é a segunda maior unidade de conservação do Estado de Minas Gerais, situa-se entre as coordenadas 20�X00 -20�X30 S e 46�X15 -47�X00 W e tem 71.525 ha. As cotas altimétricas variam entre 900 e 1200 m, atingindo um máximo de 1496 m. Dentre a formações vegetais predomina o cerrado s.l., seguido do campo rupestre, e podem ser encontrad...