Haynie, Charles Dean

This thesis describes the development of a new zero-turn-radius (ZTR) differentially driven robotic vehicle hereinafter referred to as NEVEL. The primary objective of this work was to develop a device that could be used as a test-bed for continued autonomous vehicle research at Virginia Tech while meeting the entry requirements of the Annual International Unmanned Ground Robotics Competition. In developing NEVEL, consideration was given to the vehicle s mechanical and electrical design, sensing ...

Morton, David Dean

Knowledge of land cover is important in a variety of natural resources applications. This knowledge becomes more powerful within the spatial analysis capabilities of a geographic information system (GIS). This thesis presents a digital land cover map of Virginia, produced through interpretation of 14 Landsat Thematic Mapper (TM) scenes, circa 1991-1993.The land cover map, which has a 30m pixel size, was produced entirely with personal computers. Hypercluster aggregation, an unsupervised classifi...

Person, Carl S.

This study comprises a multi-faceted case study of the growth and development of the University of Maryland Eastern Shore (UMES), with an emphasis on the leadership of Chancellor William T. Hytche during his tenure from 1975 to 1995. The study takes into account the complex, dynamic, and interrelated internal and external forces that led to the survival and subsequent development of UMES. An attempt was made to describe the relationship of Chancellor Hytche s leadership behavior and the resoluti...

Doman, David Burke

Human operator models developed using optimal control theoryare typically complicated and over-parameterized, even forsimple controlled elements. Methods for generating lesscomplicated operator models that preserve the most importantcharacteristics of the full order model are developed sothat the essential features of the operator dynamics areeasier to determine. A new formulation of the OptimalControl Model (OCM) of the human operator is developedthat allows order reduction techniques to be app...

Lewis, Edwin Carnell

The Cooperative Extension System has focused on nutrition education for low-incomefamilies for approximately 29 years via the Expanded Food and Nutrition EducationProgram (EFNEP). In response to the need for a comprehensive economic evaluationof EFNEP, Virginia Cooperative Extension (VCE) was awarded a grant from theCooperative State Research, Education and Extension Services, United States Departmentof Agriculture (CSREES, USDA) to conduct a cost benefit analysis (CBA) of nutritioneducation pro...

Lluch, Daniel Cutuli

The realm of aircraft flight dynamics analysis reaches from localstatic stability to global dynamic behavior. It includes aircraftperformance issues as well as structural concerns. In theparticular aspect of dynamicmotions of an aircraft and how we understand them, an alternatecoordinate system will be introduced that will lend insight andsimplification into the understanding of these dynamic motions. Themain contribution of this coordinate system is that one can easilyvisualize how the instanta...

Mankolo, Regine Ndole

<center>EFFECT OF POULTRY LITTER-YARD WASTECOMPOST APPLICATION ON PHOSPHORUS AVAILABILITY INDIVERSE SOILS<br>by<br>Regine N. Mankolo<p>Dr. David C. Martens, Co-chair<br>Dr. James R. McKenna, Co-chair<br>(ABSTRACT)<br></center>Land application of poultry litter has been successfully practiced for centuries to maintainand improve soil fertility, although over application may promote loss...

Zemajtis, Jerzy

The application of a mineral admixture, or a corrosion inhibitor, or a combination of both are methods used for the corrosion protection for reinforced concrete bridges. The results of a study on evaluation of corrosion inhibitors from three different manufacturers and of concretes with fly ash, slag cement, and silica fume and a concrete with silica fume and a corrosion inhibitor are presented. The specimens were built to simulate four exposure conditions typical for concrete bridges located in...

Rosas-Garcia, Victor Manuel

<p>Full grid-search semiempirical calculations (AM1 and AM1/COSMO) on zwitterionic acetylcarnitine andcarnitine, cationic acetylcholine and choline, and 3-acetoxypropanoate and 3-hydroxypropanoate in the gasphase and solution were performed. The calculated δH�X<sub>hydr</sub> for hydrolyses ofacetylcarnitine to carnitine and of acetylcholine to choline show reasonable agreement with the experimentalvalues in unbuffered solution (acetylcarni...

Liu, Binzhang M.S.

It is critical to understand WWW latencyin order to design better HTTP protocols. In this studywe characterize Webresponse time and examine the effects of proxy caching,network bandwidth,traffic load, persistent connections for a page, andperiodicity.Based on studies with four workloads, we showthat at least a quarter of the total elapsedtime is spent on establishing TCP connections with HTTP/1.0.Thedistributions ofconnection time and elapsed time can be modeled usingPearson,Weibul, or Log-logis...

Mysore, Guruprasad Jr.

<p>Inflatable dams are flexible, cylindrical structures anchored to a foundation. They are used for a variety of purposes, e.g. diverting water for irrigation or groundwater recharging, impounding water for recreational purposes, and raising the height of existing dams or spillways.<p>The vibration behavior of such dams is analyzed. Single-anchor inflatable dams with fins are considered. First, a static analysis is performed which yields the equilibrium shapes of the ...

Christiaen, Anne-Claire

Novel coatings have been designed to solveproblems associated with biofouling of marine structures,particularly ship hulls. The bestcandidates to date are multilayered coatings incorporating siliconerubber technology. These materials are efficient because they exhibitexcellent release properties. However, they arevery soft and tend to be more susceptible to various forms ofmechanical damage.Fundamental analysis of the durability of these coatings has been doneusing standard laboratory tests. Sim...

Smith, Kevin M.

Due to our love of the waterfront, almost half of the United States population now lives in coastal areas, including shores of estuaries. Unfortunately, this increasing concentration of people upsets the balance of ecosystems. My thesis project, Designing for the Waterfront - An Estuarine Research Reserve on Jones Point is about setting an example, setting a precedent for building on the waterfront. I have attempted to design an environmentally responsive and sensitive research center that will ...

Shirley, Bruce Jarrett

In discovering and forming thoughts about architectureI came to harbor a theory for all things around and withinme. A complimenting ratio of forces that, thought theirunion, create a third equally important force. 1 + 1 = 3.This concept is presented here in its raw form thoughtthe use of analogies and examples, then separated intofive simple categories demonstrating its use withinarchitecture: Preservation, Restoration, Renovation,Addition, New Fabrication. Architectural integrity ofany given pr...

Milburn, Jason S. Jr.

A random sample of injuries to employees of mechanized logging operations in the piedmont and coastal plain regions of the Southeastern U.S. was taken from the 1996-1997 claims records of three cooperating Worker s Compensation Insurance carriers. For each claim, information was gathered about the accident. Additional information on equipment, labor, and operations was gathered for each firm reporting a sample claim. All data was recorded in a spreadsheet program for sorting and analysis.&lt...

Elseifi, Mohamed A.

Thin walled stiffened composite panels, which are among the most utilized structural elements in engineering, possess the unfortunate property of being highly sensitive to geometrical imperfections. Existing analysis codes are able to predict the nonlinear postbuckling behavior of a structure with specified imperfections. However, it is impossible to determine the geometric imperfection profile of a nonexistent composite panel early in the design. This is due to the variety of uncertainties that...

Mangrum, Carl Robert Lawrence II

Laboratory scale activated sludge experiments were conducted on primary effluent municipal wastewater to evaluate the effects of anoxic selectors on controlling activated sludge bulking and foaming. These experiments were conducted with two pilot plants; a three stage anoxic selector preceding a complete mix system (experimental unit) and a complete mix system (control unit). Successful selector operation requires balancing two conflicting requirements; obtain a high substrate concentration in t...

Lewandowski, Bonny A.

LANDSCAPE IN PERIL:A CULTURAL ASSESSMENTOFTHOMASS WHARF AND WOODLANDS FARM,NORTHAMPTON COUNTY, EASTERN SHORE, VIRGINIAbyBonny A. LewandowskiCommittee Chair, Terry L. ClementsDepartment of Landscape Architecture(ABSTRACT)This thesis develops a philosophy for management, preservation, and interpretation of Woodlands Farm and Thomass Wharf in Northampton County on Virginias Eastern Shore. The U. S. Department of the Interior, National Park Service methodology for historic properties, including cult...

Woolwine, Elaine W

The purpose of the study was to identify the components of an effective workplace mentorship. Twenty-five panelists participated in a three-round Delphi study to reach a consensus on these components. The panelists were (1) local school-site teachers and school-to-work coordinators, (2) community college school-to-work coordinators, (3) directors of tech-prep consortia, and representatives from (4) business and industry, (5) labor and management, (6) corporate rsearch, and (7) federal government...

Zhang, Zhiwei

Alcohol abuse and illicit drug use in the United States are major concerns of American households, as well as of the White House. This dissertation research evaluates alcohol abuse and controlled drug use by American workers in the context of various individual, organizational, and occupational settings. It tests the importation and organizational stress perspectives, the occupation subculture perspective, and the lifecycle wage compensation theory. The analyses are developed utilizing (1) logis...

Whitfield, Cindy Carol

Steady and unsteady force and moment experiments were conducted in the Virginia Tech Stability wind tunnel using the Dynamic Plunge-Pitch-Roll (DyPPiR) model mount to perform rapid time-dependent,high-excursion maneuvers. The experiments were performed for a DARPA2 submarine model using three widely spaced 2-force-component loadcells and three tri-axial accelerometers to extract the aerodynamic loads.<p>The DARPA2 model was tested with different body configurations in two different...

Klapproth, Julia Caldwell

Through the interaction of their soils, hydrology, and biotic communities, riparian forests protect and improve water quality, provide habitat for plants and animals, support aquatic communities, and provide many benefits to humans. Virginia, along with other states in the Chesapeake Bay region, has recognized the importance of riparian forests by implementing a plan to restore forested buffers along streams, rivers, and lakes. This project reviews selected literature on riparian forest buffers,...

Mokarem, David Wayne

Chloride ion induced corrosion of reinforcing steel in concrete bridge decks has become a major problem in the United States. Latex modified concrete (LMC), low slump dense concrete (LSDC) and hot-mix asphalt membranes (HMAM) overlays are currently some of the most used rehabilitation methods. Epoxy coated reinforcing steel (ECR) was developed and promoted as a long term corrosion protection method by the Federal Highway Administration (FHWA). However, recent evidence has suggested that ECR will...

Volk Burgess, Susan Lizrene

The purpose of this study was to examine the events, processes, perceptions and changes that occurred as an elementary school faculty and a university faculty collaborated in a partnership formed by the creation of a Professional Development Academy (PDA). The study described how an elementary school faculty and a university faculty collaborated as they implemented a PDA. Research questions were: (1) What contributing factors led to the school and university faculties­ collaboration dur...

Easterbrook, Richard Brian

Predictive models have established a niche in the field of archaeology. Valued as tools in predicting potential archaeological sites, their use has increased with development of faster and more affordable computer technology. Predictive models highlight areas within a landscape where archaeological sites have a high probability of occurrence. Therefore, time and resources normally expended on archaeological exploration can then be more efficiently allocated to specified locations within a study ...

Sherfy, Mark Huffman

NUTRITIONAL VALUE AND MANAGEMENT OF WATERFOWL AND SHOREBIRD FOODS IN ATLANTIC COASTAL MOIST-SOIL IMPOUNDMENTSbyMark H. SherfyRoy L. Kirkpatrick, ChairFisheries and Wildlife SciencesABSTRACTThe mid-Atlantic coast region, an area of continental significance to migratory and wintering waterfowl and shorebirds, contains numerous moist-soil impoundments that are managed for waterbirds. Positive relationships between nonbreeding body condition and subsequent survival and reproduction have been documen...

Sabalowsky, Andrew R.

The wastewater treated at the Hopewell Regional Wastewater Treatment Facility (HRWTF) is very unique both because it is comprised of effluents of seven different industries in the area in addition to the domestic wastewater in the area, and because it reaches high temperatures in the basins, often above 45oC during the summer. Four different bench scale systems consisting of continuously stirred tank reactors (CSTRs) in series were operated during the summer of 1997 to quickly assess the feasibi...

Schaefer, Matthew David

Microwave tempering experiments were conducted on frozen blocks of shrimp (FSB) and the results were used to help determine if microwave tempering of FSB is an improved thawing method over the current, traditional method, water immersion. Results of the microwave tempering experiments were also used to help determine which microwave tempering method amongst those explored by this study is most effective.Complete thawing of a FSB in a microwave oven was found to be impractical; however, using a c...

Chen, Ying

To develop a computer tool that will give the best ship design using an optimization technique is one of the objects of the FIRST project. Choosing a containership design as a test case, the Design Optimization Tools (DOT) package is used as the optimization tool. The problem is tackled from the ship owner s point of view. The required freight rate is chosen as the objective function because the most important thing that concerns the ship owner is whether the ship will make a profit or not, and ...

Saha, Nilanjan

A system was designed to measure the effect of gap size on semi-span low Reynolds number wind tunnel experiments. The lift forces on NACA 1412, NACA 2412 and NACA 4412 half wings were measured using a strain gauge balance at chord Reynolds numbers of 100,000 and 200,000 and three different gap sizes including sealed gap. Pressure distributions on both airfoil top and bottom surfaces in the chord-wise direction near the gap were recorded for these airfoils. Also recorded was the span wise pressur...

Hughes, Steven Patrick

Clusters of low-performance spacecraft flying in formation mayprovide enhanced performance over single high-performancespacecraft. This is especially true for remote sensing missionswhere interferometry or stereographic imaging may provide higherresolution data. The configurations of such formations varyduring an orbit due to orbital dynamics, and over longer timescales due to perturbations. Selection of a configuration shouldbe based on overall performance of the formation. In this thesis,perfo...

Neel, Reece E.

Computational solutions are presented for flows ranging fromincompressible viscous flows to inviscid transonic flows. Theviscous flow problems are solved using the incompressibleNavier-Stokes equations while the inviscid solutions are attainedusing the full potential equation. Results for theviscous flow problems focus on turbulence modeling when separation ispresent. The main focus for the inviscid results is thedevelopment of an unstructured solution algorithm.The subject dealing with turbulen...

Cheynet, Kyla Ingeborg

The effects of two forms of mid-rotation release on thinned, fertilized loblolly pine (Pinus taeda L.) plantations in Virginia were examined: aerial imazapyr and basal triclopyr application. Imazapyr measurement plots were installed in nine Piedmont and twelve Coastal Plain plantations operationally released with imazapyr, and triclopyr measurement plots were installed within a controlled fertilization/release study spanning both regions. No differences in volume were detected following triclopy...

Fung, Jimmy Jr.

A parametric identification procedure is proposed that combinesthe method of multiple scales and higher-order statistics toefficiently and accurately model nonlinearsystems. A theoretical background for the method ofmultiple scales and higher-orderstatistics is given.Validation of the procedure is performedthrough applying it to numerical simulations of twononlinear systems. The results show how the procedure cansuccessfully characterize the system damping and nonlinearities anddetermine the cor...

Donovan, Erin Patricia

Two critical components of the United States civil infrastructure, bridges and roads, have deteriorated in the past two decades at an accelerated rate and are in need of maintenance and rehabilitation. Geosynthetics may have the potential to provide a long-term solution to some of the problems that are present in these roads and bridges. When installed properly, some geosynthetics can act as both a moisture barrier and stress absorption layer. However, the tack coat application rate is critical ...

Rogers, Susan Owen

The federally endangered tan riffleshell (<I>Epioblasma florentina walkeri</I>) is restricted to only one known reproducing population, in Indian Creek, Tazewell County, Virginia. Attempts to recover this species by augmenting relic populations throughout its historic range are aided through knowledge of its population biology and requirements in culture environments. Infestations of host fish (fantail darters, <I>Etheostoma flabellare</I>)...

Kumar, Abhishek

The need to design a controller that self-schedules itself during the flight of anaircraft has been an active area of research. New methods have been developed beyondthe traditional gain-scheduling approach.One such design method leads to a linear parametervarying (LPV) controller that changes based on the real-time variation of system dynamics.Before sucha controller can be designed, the system has to also be represented as an LPV system.The current effort proposes a LPV modeling technique that...

Liu, Youhua

The aerospace industry is increasingly coming to the conclusion that physics-based high-fidelity models need to be used as early as possible in the design of its products. At the preliminary design stage of wing structures, though highly desirable for its high accuracy, a detailed finite element analysis(FEA) is often not feasible due to the prohibitive preparation time for the FE model data and high computation cost caused by large degrees of freedom. In view of this situation, often equivalent...

Mugtussids, Iossif B.

Modern aircraft are capable of recording hundreds of parameters duringflight. This fact not only facilitates the investigation of anaccident or a serious incident, but also provides the opportunity to usethe recorded data to predict future aircraft behavior. It is believedthat, by analyzing the recorded data, one can identify precursors tohazardous behavior and develop procedures to mitigate the problemsbefore they actually occur. Because of the enormous amount of datacollected during each fligh...

Gomez, Jesus Emilio

Development of an Extended Hyperbolic Model for Concrete-to-Soil InterfacesbyJesús E. GómezDr. George M. Filz, ChairmanVia Department of Civil EngineeringABSTRACTPlacement and compaction of the backfill behind an earth retaining wall may induce a vertical shear force at the soil-to-wall interface. This vertical shear force, or downdrag, is beneficial for the stability of the structure. A significant reduction in construction costs may result if the downdrag is accounted for dur...

Wayman, Jared Paul

In cooperation with the USDA Forest Service Southern Research Station, an algorithm has been developed to replace the current aerial-photography-derived FIA Phase 1 estimates of forest/non-forest with a Landsat Thematic Mapper-based forest area estimation. Corrected area estimates were obtained using a new hybrid classifier called Iterative Guided Spectral Class Rejection (IGSCR) for portions of three physiographic regions of Virginia. Corrected area estimates were also derived using the Landsat...

Stancil, Vann Franklin

I collected fish samples and habitat data at 43 sites throughout the upper Roanoke River watershed, Virginia. Sites were separated into three watershed areas size classes: 10 15, 20 30, and 70 80 km <sup>2</sup>. I correlated physical in-stream conditions with proportions of forest, disturbed, and herbaceous/agricultural land at various watershed-scales to determine factors affecting stream habitat. I grouped fishes into metrics commonly used in indexes of biotic inte...

Pennington, Timothy L.

Three--dimensional mapping has manyapplications includingrobot navigation, medical diagnosis and industrialinspection. However, many applications remain unfilleddue to the large size and complex nature of typical3--D mapping systems. The use of fiber optics allowsthe miniaturization and simplification of many optical systems.This research used a fiber optic coupler toproject a fringe pattern onto an object to be profiled. Thetwo outputs fibers of thecoupler were brought close together toform the...

Liu, Dongmin

Japanese quail were used as animal models in four experiments to evaluate the effects of supplementing diets with different lipids on bone chemical, mechanical, and histological properties. In Exp. 1, laying hens were fed a basal diet containing either 5% soybean oil (SBO), hydrogenated soybean oil (HSBO), chicken fat (CF), or menhaden fish oil (FO). The addition of SBO in the maternal diet increased the levels of total n-6 fatty acids and arachidonic acid (AA, 20:4n-6) in yolk and tibial bones ...

Shafer, Paula L.

Mineralogical and Geochemical Variations in theOld Hickory Heavy Mineral Sand Deposit,Sussex and Dinwiddie Counties, VAPaula L. ShaferABSTRACTThe Old Hickory mine is a world class placer titanium deposit located at the boundary of the Coastal Plain and the Piedmont in Virginia, astride the Sussex-Dinwiddie county line (77º34 W Long, 36º55 N Lat., Cherry Hill Quad). The Old Hickory deposit, discovered in 1987 by C. R. Berquist, was opened as a commercial mine in 1997, and is pre...

Subramanian, Anbumani

Given 2D images, it still remains a big challenge in the field ofcomputer vision to group the image points into logical objects(segmentation) and to determine the locations in the scene (rangeestimation). Despite the decades of research, a single solutionis yet to be found. Through our research we have demonstratedthat a possible solution is to use moving aperture lens. This lenshas the effect of introducing small, repeating movements of thecamera center so that objects appear to translate in th...

Grenville, Delia N.

A study was conducted to determine the preferences for the design of distributed meeting rooms used for video enhanced electronic meeting systems (VEMS). Although there is a significant body of literature in the group communication domain, the research in this multidisciplinary area has paid minimal attention to users environmental preferences in the design of a meeting space.A basic science approach through three studies was used to explore the variables that defined the design of a distributed...

Chan, Matthew D.

This research tested the ability of fish morphology to predict membership of fishes in habitat guilds, their swimming performance, and habitat preference. Further, it considered methods for choosing a surrogate species to identify habitat of target species. Morphological discriminant functions were developed using morphological traits of fishes from one river to identify membership in two habitat guild systems (mesohabitat and microhabitat). Functions were then used to test factors influencing c...

de la Riva, Diego Horacio

Measurements of the turbulent flow field through a highly staggered cascade propulsor configuration in the Virginia Tech cascade wind tunnel have been taken. Predictions of the same flow using Rapid Distortion Theory (RDT) were performed. Measurements and predictions were compared. The comparison was oriented to check the aptness of RDT in describing this kind of flow.Since this study represents the initial steps of a major project, the RDT model was kept simple. The non-penetration condition (b...

Dadson, Daniel K

State Departments of Transportation (DOT s) have established Bridge Management Systems (BMS) with procedures to aid in estimating service lives of bridge components and elements. Service life estimates, together with cost information, are used to develop life-cycle costs of bridges. These estimates are necessary to prioritize and optimize bridge improvement programs within budgetary constraints. Several factors, including age, traffic, and environment have been identified in current BMS literatu...