ETDs: Virginia Tech Electronic Theses and Dissertations
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Virginia Tech has been a world leader in electronic theses and dissertation initiatives for more than 20 years. On January 1, 1997, Virginia Tech was the first university to require electronic submission of theses and dissertations (ETDs). Ever since then, Virginia Tech graduate students have been able to prepare, submit, review, and publish their theses and dissertations online and to append digital media such as images, data, audio, and video.
University Libraries staff are currently digitizing thousands of pre-1997 theses and dissertations and loading them into VTechWorks. Most of these theses and dissertations are fully available to the public, but we will, in general, honor requests by the item's author to restrict access to Virginia Tech only. See our process for Requesting that Material be Amended or Removed.
To search all Virginia Tech print and digital theses and dissertations, use the University Libraries ETD resource guide.
Materials that are restricted to Virginia Tech only may be requested via your own university or public library's Interlibrary Loan program or through the VTechWorks request form that appears when you try to access the item. You might also be able to obtain a copy of the work through ProQuest's database of theses and dissertations. If you are on a Virginia Tech campus but are unable to find the pre-1997 thesis or dissertation you are seeking in VTechWorks, you may also be able to order a physical copy from library storage. Please check the library catalog at http://www.lib.vt.edu/ for physical copies.
The guidelines that apply to Virginia Tech's graduate students as ETD authors can be found at http://guides.lib.vt.edu/ETDguide.
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Browsing ETDs: Virginia Tech Electronic Theses and Dissertations by Content Type "Thesis"
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- 1/2Yadao, Albert (Virginia Polytechnic Institute and State University, 1994)The Situation. Downtown. An alleyway and adjacent building form the volumetric parametric parameters for a hypothetical, semi-urban addition. The Program. A synthesis of bookstore, art gallery, and cafe outlines the necessary conditions to be featured in the proposed building. The Strategy. To actualize each element of the program while attempting to construct, through minimal intervention, a space which maximizes the cross-sectional aspects of the situation and the internal organization of the program.
- A 1000-year sedimentary record of hurricane, fire, and vegetation history from a coastal lagoon in southwestern Dominican RepublicLeBlanc, Allison Renee (Virginia Tech, 2011-03-24)Our knowledge of whether hurricanes cause lasting changes in forest composition and the patterns and role of fire in Caribbean dry forests are lacking. This project combines paleoecological and paleotempestological methods to document the disturbance and environmental history of the last 1000 yrs at Laguna Alejandro, situated in the lowland dry forests of arid SW Dominican Republic. I analyzed multiple proxy data sources of a 160 cm coastal lagoon sediment profile. High-resolution (1 cm) sampling for loss-on-ignition and magnetic susceptibility indicated multiple erosion and hurricane events, including a hurricane ~996 cal YBP, and several erosion events and hurricanes between ~321 cal YBP and present day. Pollen analysis documented 32 plant families with most levels dominated by pollen of Fabaceae (legumes), the Urticales order, and Cyperaceae (sedges), though families of upland and montane vegetation are also present ~510-996 cal YBP. All pollen slides contained microscopic charcoal indicating the occurrence of regional or extra-local fires over the last ~1000 yrs. Local fires, as indicated by macroscopic charcoal, occurred before ~434 cal YBP and may be tied to hurricanes, increased moisture in the region (thereby increased fuel and ignition chances), or prehistoric human activities. Pollen spectra representing periods before and after disturbance events were similar and may support the idea of forest resilience, but more samples are needed. Multiple erosion events between ~294 cal YBP and present may be tied to hurricanes or tropical storms and increasing late-Holocene aridity in the region as documented by several studies from the Caribbean.
- 118 Jefferson StreetLimer, David W. (Virginia Polytechnic Institute and State University, 1996)
- The 11th Virginia Infantry Regiment, C. S. ABell, Robert T. (Virginia Polytechnic Institute, 1968)This thesis is a socio-military history of a Confederate infantry regiment. Formed principally of Lynchburg City and Campbell County men, the Regiment fought in the Civil War as part of Kemper's Brigade, Pickett's Division, Longstreet's Corps, Lee's Army of Northern Virginia. Through diaries, letters, memoirs and contemporary newspapers, the writer has traced the Regiment from its inception as individual companies formed in reaction to John Brown's Raid until its surrender at Appomattox. The entire effort focuses, whenever possible, upon the officers and men of the Regiment. Thus, little attention is paid to grand strategy or national politics. Instead, drum rolls call the Regiment into formation for marches to unknown fields. The men fight in battles that later give the fields a place in history: First Manassas, Seven Pines, Frayser's Farm, Second Manassas, Antietam, Fredericksburg, Suffolk, Gettysburg, Plymouth, Drewry's Bluff, Cold Harbor, Bermuda Hundred, Five Forks and Sayler's Creek. Even in battle, the emphasis remains on the Regiment. Success or failure is measured by how the men felt they had performed, rather than whether or not the army achieved victory. The final result for the men of the 11th Virginia was defeat and surrender; yet, having suffered incredible hardship and having faced overwhelming odds, they emerged as rather heroic individuals. The thesis treats neither victory nor defeat, but men who gave their best for a cause in which they had complete faith.
- A 15-Year Research Summary and Hunting Harvest Data Evaluation of the Broad Run Management AreaWeekes, William Dickey (Virginia Tech, 1974)This thesis is serving as a study report on 15 years or wildlife research performed at the 11,422-acre Broad Run Wildlife Research Area, also known at the Broad Run Management Area, in Craig County, Virginia, Incorporated in this thesis is a synthesis of all pertinent data, conclusions, evaluations, and recommendations emanating from the 17 theses written from studies undertaken at Broad Run. From these 17 theses there has been gleaned 193 results which are included in this thesis. These results took the form as either facts, summary conclusions, distilled background discussions, or as evaluations on information unearthed or research performed. Five works emanating from studies at Broad Run concerned attempts to quantify browse and mast. Four theses concerned the wild turkey, its movements, distribution, and abundance as influenced by wildlife management practices. Three theses concerned deer, its abundance and the influence, if any, on its population by dogs. Two theses were concerned with such wildlife practices as agricultural clearings and herbicide use, while the remaining theses were on the subjects of wild grapes, birth control in foxes, climate as an influence on the deer hunter, and the influence of forest habitat on songbird populations.
- The 16S rRNA characterization of a novel "microaerophilic" Pseudomonas sp. from the oligotrophic deep subsurface environmentLampe, Robert Carl III (Virginia Tech, 1996-11-07)A gram negative microaerophilic bacterium, designated Pseudomonas sp. strain MR 100, was isolated from a depth of 463 meters at the Savannah River DOE site and identified using 16S rDNA sequencing and DNA-DNA reassociation. Micro aerophiles from the Middendorf formation were isolated by use of a semi-solid agar assay, and constituted 10% of the plateable microorganisms. Genetic identification involved the isolation of genomic DNA and amplification of the gene encoding 16S rRNA by PCR, using universal primers. The amplified DNA was sequenced and compared to 16S rRNA sequences in Genbank. High sequence similarity (98.5%) was observed with the Pseudomonas mendocina type strain, indicating a similarity to the (Group I) pseudomonads. DNA-DNA reassociation was performed between Pseudomonas sp. strain MR 100 and 11 representative p seudomonads using the S 1 nuclease method. Strain MR 100 was found to be 20% homologous to the Pseudomonas mendocina type strain, 10% homologous to Pseudomonas alcaligenes, and 5% homologous to Pseudomonas aeruginosa. Data from biochemical tests confirm the hypothesis that strain MR 100 is a novel species of Pseudomonas
- The 17th Regiment Virginia Volunteers, C.S.A.Siburt, James T. (Virginia Polytechnic Institute and State University, 1977)This thesis is a socio-military history of a Confederate infantry regiment. Formed of companies from the city of Alexandria and surrounding counties, the Regiment fought in the Civil War as part of Corse's brigade, Pickett's division, Longstreet's Corps, Lee's Army of Northern Virginia. Through diaries, memoirs, letters and newspapers, the writer has traced the Regiment from its beginnings as individual companies to its last hours at Appomattox. Whenever possible the narrative focuses on the officers and men who comprised.the unit. Therefore, except to provide clarity, little attention is paid to the movements of sister regiments, overall strategy or politics. Instead the emphasis is on the soldiers perceptions of his experiences in camp, on the march and the battlefield. Seeing extensive action, the Regiment fought at Blackburn's Ford, Williamsburg, Seven Pines, Frayser's Farm, Second Manassas, South Mountain, Antietam, Fredericksburg, Suffolk, Manassas Gap, Flat Creek, Drewry's Bluff, Bermuda Hundred, Five Forks and Sayler's Creek. Success or failure is measured by the units' individual performance and therefore is not evaluated with the army as a whole. Appomattox brought defeat and surrender to the men of the 17th Virginia. However, the designation of victor and vanqished is of secondary importance. Duty faithfully performed, in spite of incredible hardship, in the face of overwhelming odds, by a band of heroic, valiant men is the more enduring memory.
- The 1934 Indian Reorganization Act and Indigenous Governance: A Comparison of Governance of Santa Clara Pueblo and the Turtle Mountain Band of Chippewa Nations — 1991 – 2000LaRoque, Kent A. (Virginia Tech, 2004-06-23)Native American communities are continually impacted by Federal Indian policy. Over one-half of all Native American nations function politically under the provisions of the 1934 Indian Reorganization Act (IRA). There are claims that many of these Native American communities experience intra-tribal conflict due to the lack of congruence between the tribal governments formed under the IRA and cultural traditions of governance. This claim was investigated via a comparative trend analysis of the Santa Clara Pueblo, operating politically under the IRA provisions, and the Turtle Mountain Band of Chippewa, operating under a constitutional form of governance outside of IRA provisions. After an historical analysis, an evaluation of tribal constitutions, and an examination of news media coverage for the period of 1991 – 2000, the project concluded that the legacies of the IRA are not the primary causal agent of intra-tribal conflict.
- The 1949 campaign for the Democratic Gubernatorial nomination in VirginiaEdwards, Clarence Maurice (Virginia Polytechnic Institute and State University, 1973)The writer's treatment of the 1949 Democratic Gubernatorial Primary offers an examination of Virginia's political climate, the candidates and their campaigns. In addition, the presentation contains an analysis and evaluation of the charges of campaign "misconduct" leveled at the Byrd Organization. Senator Harry F. Byrd's Harrisonburg speech, not Republican votes, won the Democratic gubernatorial nomination for John Stewart Battle. The 1949 Democratic Primary revealed the existence of a new Byrd Organization faction that was disenchanted with the "best government governs least" philosophy.
- The 1993 North Korean Nuclear Crisis: A Foreign Policy AnalysisLee, Ergene (Virginia Tech, 2000-05-05)In this paper I apply the Rational Actor model to the 1993-1994 North Korean Nuclear Crisis. I begin with two hypotheses: 1) North Korea attempted nuclear armament because of its perception of threat from South Korea and the United States; 2) North Korea attempted nuclear armament because it wanted to use its nuclear program as leverage to obtain economic assistance from the United States. I conduct a diplomatic historical analysis based on the Rational Actor model to determine which was North Korea's primary objective, and conclude that the primary objective of North Korea was obtaining economic concessions, but that threat perception did seem to play a role in the decision to start the nuclear program. In this process, I show that the Rational Actor model was insufficient in the analysis and that it must be complemented by cultural factors, "thickening" the rationality.
- 2 Questions: what becomes architectureLambert, Joseph Edward (Virginia Tech, 1998-01-13)For several years, certain personal efforts relied heavily upon an essential belief in Lou Kahn's masterful answer to a student's question, because Architecture is. Kahn's spiritual awareness brought about a poetic significance to the studying, learning, and actualizing of our environmental efforts. Through his profoundly simple answer of architecture's essential existence, Kahn suggested that our works could never reach this state of being (even reason being unable to reach to far), leaving us only the ability to aspire towards it- with works ever to it, never with works of it. In the despair of our Modern response we set to achieve an end worth of its recognition which simply fails to acknowledge that the question was one of why, not one of what. His answer, and its suppressive conditions of existence, is no longer solely acceptable to a student's question. To my Master I say, reconception is necessary; the answer requires a more dynamic essence. As it is with the nature and dynamic flow of all 10,000 things- one can never exist, though one is always existing; one can never live , though one is always living, and in our cultural and social attempts to assimilate and accommodate our environment- our attempts will never be, only ever becoming. In other words, Mr. Kahn, I would like to supplicate and supplement, because Architecture becomes.
- 20,000 Fewer: The Wagner-Rogers Bill and the Jewish Refugee CrisisWalters, Kathryn Perry (Virginia Tech, 2019-07-11)In the fall of 1938, Marion Kenworthy, child psychologist, and Clarence Pickett, director of the American Friends Service Committee, began designing a bill that would challenge the United States's government's strict immigration laws and allow persecuted children to come to the United States and live in American homes. The Wagner-Rogers Bill, named for Senator Robert Wagner of New York and Representative Edith Rogers of Massachusetts and introduced in February 1939, sought to allow the entry of 20,000 refugee children from Germany. At the time, multiple domestic factors limited the willingness of American politicians to meet this problem head on: high unemployment rates after the stock market crash in 1929, an isolationist sentiment after the impact of World War I, and xenophobia. These factors discouraged the lawmakers from revising the quota limit set on obtainable visas established by the 1924 Immigration Act and allow outsiders into the United States. These few actors who supported the Wagner-Rogers Bill reflect a hidden minority of the American public and political body that fought to help Jewish refugees by standing up to the majority of citizens and politicians against higher immigration into the United States, and the story of the this Bill demonstrates what might have been possible and illuminates 20th century models of American humanitarianism and its role in creating international refugee protection.
- The 21st Century Cancer Care Wellness Facility: A Study, Interpretation, and Application of 16th Century Japanese Tea-house ThemesCoffey, Shaun C. (Virginia Tech, 2016-01-28)Buildings which address space through all the senses, rather than being dominated by ocular centric considerations solely, have become the minority within the discipline of Architecture. This can create an imbalance, perceivable as feelings of estrangement and detachment for the inhabitant. Estrangement is particularly evident within health care architecture, which owes much of its current form to ideas developed during Modernism. In response to this imbalance, Architecture from the past may have lessons which can be applied. This thesis investigates the potential of applying spatial techniques and approaches learned from the 16th century Japanese tea-house. A health care building which benefits from the same kind of reflective and contemplative spaces inherent in the tea-house includes counseling facilities, and therefore an outpatient cancer care center was chosen to apply these lessons. Among the techniques researched and applied, the use of a sequential vision of spatial experience, which reveals the building in stages and facilitates spaces for pause and reflection, was particularly powerful. The result is a building with spaces that take on an almost sacred tone, where one can be at peace with the realities of their current situation, and begin thinking about the path forward.
- 24 hr Building: A Study into the Cyclical Nature of ArchitectureLancaster, James (Virginia Tech, 2008-09-12)We live in a society dominated by time. It plays a part in nearly everything we do. Time tells us when to wake up, when to eat, when to be at work, when its time to sleep, and so on. Just as people are controlled by time, so are the buildings we use. Th ese buildings oft en times are very narrowly used. As a result, portions of our cities are full of activity during certain times of the day, while at other times become deserted. What happens to the building when it is not being used? Does the building go to sleep? Do buildings need to sleep? Is it possible to design a mixed-use building in our nations capitol that never sleeps? Th ese are just a few of the questions that began this journey to design 24 hours building and the cyclical nature of the people that inhabit them.
- 252 Columns: The Development of an Archetypal FormShorb, John J. Jr. (Virginia Tech, 2000-07-18)A good urban space must fulfill the promises of complexity and variety. This thesis investigates how to define an urban plaza in terms of universal elements employed to achieve that complexity. An alternating grid, a, b, a, composed of squares of five and ten feet provides an order for all the elements on the site. Each element is generated and organized from this grid. The dominant elements are thirty-foot tall concrete columns. These columns and their subsequent structural armature define the structure of buildings and an underground parking structure. The columns form a continuum which ties together every aspect of the thesis. Visually, they are present everywhere in the plaza and define very specific views of the plaza and the surrounding city. Together with an intricate mosaic floor pattern created from overlapping ellipses, also based on the grid, the massive columns and fine-grained floor define the extremes of the plaza's scale. The development of a number of potential elements always failed when put together to form a cohesive idea of a contained plaza. A clear order was necessary to bring together different elements into a cohesive whole. This led to the definition of a plaza as a sensibly apparent and rationally knowable outdoor public building contained within a city or town. For an area which previously lacked any structural cohesion, the ordered plaza now defines a strong structural element within the city. The grid and columns define space but do not force a single usage. They define how the plaza is used as it weathers the continual change of an urban environment. The plaza does not exist as an independent element within the city. The many framed views offered by the columns create new perspectives of the surrounding city. The universal elements, the columns, reference the site specifically in their scale and proportion. Applicable in a wide range of projects, the grid of columns in this project orders a pedestrian environment connecting downtown and a baseball stadium. Three buildings which derive directly from the grid create additional small openings to the city beyond. While focusing toward the center, the buildings define a permeable edge which allows interaction.
- The 28th Virginia Infantry Regiment, C.S.A.Fields, Frank E. (Virginia Tech, 1984-05-05)In the Spring of 1861, men from Roanoke, Botetourt, Craig and Bedford Counties enlisted in Confederate service and became members of the 28th Virginia Infantry Regiment. Their story is an integral part of the history of Lee's Army of Northern Virginia. This is a social-military study which documents the war-time careers of the men in the 28th Virginia. Letters, diaries, personal accounts and other primary sources were utilized in addition to various secondary sources. An examination of letters and diaries written by soldiers in the 28th Virginia is vital for one to understand Civil War army life. The 28th Virginia participated in most of the major eastern campaigns. As a part of Longstreet's corps, Pickett's division, they fought at 1st and 2nd Manassas, Seven Day's battles, Sharpsburg, Gettysburg, Seige of Richmond and Petersburg and the retreat to Appomattox.
- 2D CFD Simulation of a Circulation Control Inlet Guide VaneHill, Hugh Edward (Virginia Tech, 2007-01-15)This thesis presents the results of two 2-D computational studies of a circulation control Inlet Guide Vane (IGV) that takes advantage of the Coanda effect for flow vectoring. The IGV in this thesis is an uncambered airfoil that alters circulation around itself by means of a Coanda jet that exhausts along the IGV's trailing edge surface. The IGV is designed for an axial inlet flow at a Mach number of 0.54 and an exit flow angle of 11 degrees. These conditions were selected to match the operating conditions of the 90% span section of the IGV of the TESCOM compressor rig at the Compressor Aero Research Laboratory (CARL) located at Wright-Patterson AFB. Furthermore, using the nominal chord (length from leading edge of the IGV to the jet exit) for the length scale, the Reynolds number for the circulation control IGV in this region was 5e⁵. The first study was a code and turbulence model comparison, while the second study was an optimization study which determined optimal results for parameters that affected circulation around the IGV. Individual abstracts for the two studies are provided below. To determine the effect of different turbulence models on the prediction of turning angles from the circulation control IGV, the commercial code GASP was employed using three turbulence models. Furthermore, to show that the results from the optimization study were code independent a code comparison was completed between ADPAC and GASP using the Spalart-Allmaras turbulence model. Turbulence models employed by GASP included: two isotropic turbulence models, the one equation Spalart-Allmaras and the two-equation Wilcox 1998 k-ω. The isotropic models were then compared to the non-isotropic stress transport model Wilcox 1998 Stress-ω. The results show good comparison between turning angle trends and pressure loss trends for a range of blowing rates studied at a constant trailing edge radius size. When the three turbulence models are compared for a range of trailing edge radii, the models were in good agreement when the trailing edge is sufficiently large. However, at the smallest radius, isotropic models predict the greatest amount of circulation around the IGV that may be caused by the prediction of transonic flow above the Coanda surface. The optimization study employed the CFD code ADPAC in conjunction with the Spalart-Allmaras turbulence model to determine the optimal jet height, trailing edge radius, and supply pressure that would meet the design criteria of the TESCOM (TESt COMpressor) rig while minimizing the mass flow rate and pressure losses. The optimal geometry that was able to meet the design requirements had a jet height of h/Cn = 0.0057 and a trailing edge Radius R/Cn = 0.16. This geometry needed a jet to inflow total pressure ratio of 1.8 to meet the exit turning angle requirement. At this supply pressure ratio the mass flow rate required by the flow control system was 0.71 percent of the total mass flow rate through the engine. The optimal circulation control IGV had slightly lower pressure losses when compared to the cambered IGV in the TESCOM rig.
- 2D Jupyter: Design and Evaluation of 2D Computational NotebooksChristman, Elizabeth (Virginia Tech, 2023-06-12)Computational notebooks are a popular tool for data analysis. However, the 1D linear structure used by many computational notebooks can lead to challenges and pain points in data analysis, including messiness, tedious navigation, inefficient use of screen space, and presentation of non-linear narratives. To address these problems, we designed a prototype Jupyter Notebooks extension called 2D Jupyter that enables a 2D organization of code cells in a multi-column layout, as well as freeform cell placement. We conducted a user study using this extension to evaluate the usability of 2D computational notebooks and understand the advantages and disadvantages that it provides over a 1D layout. As a result of this study, we found evidence that the 2D layout provides enhanced usability and efficiency in computational notebooks. Additionally, we gathered feedback on the design of the prototype that can be used to inform future work. Overall, 2D Jupyter was positively received and users not only enjoyed using the extension, but also expressed a desire to use 2D notebook environments in the future.
- 2GHz W-CDMA Radio TransceiverCheung, Tze Chiu (Virginia Tech, 1998-12-15)A radio transceiver has been designed and built for a W-CDMA experimental system operating at 2GHz. The radio is an RF front-end for mobile terminals. The radio provides the functions of modulation and demodulation to enable transmitting and receiving digital information through the air link. The radio comprises one transmitter in conjunction with transmit power control (TPC), two independent receivers in conjunction with automatic gain control (AGC) and automatic frequency control (AFC), and one common synthesizer. Data exchange between the radio and the baseband processor takes place in an 8-bit digital format. Digital-to-analog converters (DAC) at the transmitter and analog- to-digital converters (ADC) at the receivers provide the interface between the radio and the baseband processor. DACs are also used to convert the 7-bit command codes from the processor to analog signals for the TPC, AGC and AFC. The radio transceiver is designed to meet the stringent requirements imposed by the W-CDMA system. The 70dB TPC enables the adaptive power control for combating the near-far problem. The high linearity of the transmitter provides the use of linear modulation with less than 40dBc adjacent channel power suppression. The 0.03125ppm tuning resolution of the AFC maximizes the receiver sensitivity. The 80dB AGC produces a constant demodulated signal level to the ADC regardless of the RF signal level. This thesis documents the design methodology for this radio transceiver.
- 3-D finite element beam/connector model for a glulam dome capTsang, Moses T. (Virginia Tech, 1992)The purpose of this study is to model the beam/decking connectors (nails) of a glulam dome cap by beam/connector elements, and to analyze various dome cap models in order to investigate the potential of the beam/connector model to simulate the decking. Two- and three-dimensional beam/connector elements are formulated, tested, and evaluated. The dome cap is modeled with I-DEAS, and the modeling procedures are briefly discussed. Four series of beam/connector dome cap models are created and analyzed: (1) models with the nailed joints at bracing points (rigid link h=0), (2) models with the nailed joints at bracing points (h>0), (3) models with 16 nailed joints per beam element (h=0), and (4) models with 16 nailed joints per beam element (h>0). Their results are compared with the dome cap models with the truss bracings. Finally, conclusions and recommendations for future research are presented.