Dissertations / Theses: 'LD5655.V855 1991.M446'

1

McCormick, Amy J. "The effects of pH on the biodegradation of benzene, toluene, ethylbenzene, m-Xylene in soils." Thesis, This resource online, 1991. http://scholar.lib.vt.edu/theses/available/etd-10222009-124953/.

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2

McCall, Ronald Gene. "Transformation: a change of order and the growth of form." Thesis, Virginia Polytechnic Institute and State University, 1991. http://hdl.handle.net/10919/53295.

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Through an analogical process, this thesis explores the concept of transformation as it affords opportunities for order and structure in architecture. Beginning with the square as the seed from which the projects develop, orthogonal grids are employed as a means for developing ordering geometries as form-giving structures. A historical reference, deriving structure and form from a square grid instantiates development of the theme. Having examined some conditions of transformation in architecture, the work turns to a consideration of some personal explorations of transformation that may be of use in future architectural undertakings. The consequent forms are not intended to justify the particular transformational grammars; rather they are to be taken as models for future development.
Master of Architecture

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3

McCain, Wilfred C. "Cardiovascular components of organophosphorus-induced delayed neuropathy." Thesis, Virginia Tech, 1991. http://hdl.handle.net/10919/41691.

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The focus of this study was to assess the cardiovascular effects in hens of a single 2.5 mg/kg intramuscular injection of phenyl saligenin phosphate (PSP) into the breast muscle. Parameters were measured at 1, 3, 7, and 20 days post treatment. All hens developed clinical signs of delayed neuropathy by day 10 and these signs were maximal by day 20. Alterations of measured parameters were observed prior to the onset of clinical signs of organophosphorus-induced delayed neuropathy (OPIDN) (days 1, 3, and 7) as well as when maximal clinical signs were evident (days 15-21). Significant decreases in the activities of brain NTE and plasma cholinesterase as well as decreases in weight and the level of pcO2 and an increase in peripheral resistance were observed prior to evidence of clinical signs of OPIDN. When maximal signs of OPIDN were present, brain NTE and plasma cholinesterase were at control levels but brain cholinesterase was significantly increased. Significant decreases in body weight and arterial pCO2 and significant increases in limb venous flow, arterial blood pressure, and hematocrit were seen at this time.
Master of Science

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4

McGregor, Roberta J. "Expert practice and career progression in selected clinical nurse specialists." Diss., This resource online, 1991. http://scholar.lib.vt.edu/theses/available/etd-07282008-135236/.

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5

Melnyk, Glenn J. "Mechanisms for automated toolhead changing in nuclear steam generator robotics." Thesis, This resource online, 1993. http://scholar.lib.vt.edu/theses/available/etd-06302009-040338/.

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6

Menegay, Peter. "Experimental investigation of an ejector as a refrigerant expansion engine." Thesis, This resource online, 1991. http://scholar.lib.vt.edu/theses/available/etd-10222009-124957/.

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7

Mehrotra, Meeta. "Wife abuse among Indians in the U.S." Thesis, This resource online, 1995. http://scholar.lib.vt.edu/theses/available/etd-02132009-172609/.

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8

Mevorah, Jack Elliot. "Music and architecture : from object to event /." Thesis, This resource online, 1998. http://scholar.lib.vt.edu/theses/available/etd-08252008-162706/.

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9

McCurdy, Michael W. "Chemical reduction and oxidation combined with biodegradation for the treatment of a textile dye wastewater." Thesis, This resource online, 1991. http://scholar.lib.vt.edu/theses/available/etd-10102009-020050/.

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10

Meng, Ronald L. "Design of moment end-plate connections for seismic loading." Diss., This resource online, 1996. http://scholar.lib.vt.edu/theses/available/etd-11082006-133629/.

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11

Merritt, John M. "The effect of increasing a person's computer self-efficacy on his or her intentions to use a computer." Thesis, This resource online, 1994. http://scholar.lib.vt.edu/theses/available/etd-05092009-040405/.

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12

Meunier, Pierre. "Psychophysical assessment of load-carrying in internal and external-frame backpacks." Thesis, This resource online, 1994. http://scholar.lib.vt.edu/theses/available/etd-05022009-040630/.

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13

Meinert, Todd Richard. "Factors affecting the accuracy and stability of sire proofs from progeny test herds." Diss., Virginia Tech, 1991. http://hdl.handle.net/10919/39701.

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Change in Modified Contemporary Comparison proofs during first and second crop period was computed from up to eight proofs during both periods for AI and non-AI sampled Holstein bulls with repeatability of last evaluation≥.90. Effect of proof number within testing period on the bull's milk or fat evaluation was estimated with bull absorbed. AI and non-AI sampled bulls' proofs increased from initial first crop proof and then remained fairly constant during the remainder of first crop period. With inclusion of second crop daughters, proofs dropped significantly more for non-AI than AI sampled bulls. This drop increased for non-AI sampled bulls born after 1976, but was unchanged for AI sampled bulls. A measure of change was calculated using last second crop proof minus the second to last first crop proof. Expected standard deviation of change was calculated and used to stratify bulls into eight change classes. A larger proportion of non-AI sampled bulls have proofs that dropped than could be explained by chance alo e. Results indicated that non-AI sampled bulls were less stable than AI sampled bulls' proofs and that stability of non-AI sampled bulls has diminished over time. For one of the studs that had stability of their bulls' proofs examined, their young sire sampling program was investigated. Individual phenotypic and genetic records of first crop and non-first crop cows in 3449 herds participating in the AI stud's young sire sampling program from 1971 to 1987 were used to characterize the sampling program, to estimate genetic trend across and within the progeny test herds, and to compute within herd means and standard deviations of various traits (herd characteristics). Herd characteristics of progeny test herds were utilized in predicting within herd genetic trend d in predicting changes in proofs of bulls sampled by the stud. For bulls sampled by this stud, average herd characteristics and variability of herd characteristics across the contributing herds was calculated and used to predict the measure of proof change in the first study. Average herd-year characteristics and variability of herd-year characteristics explained 39% to 46% of the variation in milk. and fat proof changes. In general, variability of herd-year characteristics and average within herd-year standard deviation herd-year characteristic variables explained most of the changes in proofs. Genetic trend across the progeny test herds was large for milk (105 kg) and fat (3.1 kg) yield. Genetic trend computed from PTAs of sires of first crop cows increased 58 kg milk and 1.5 kg fat per year from 1971 to 1978 and 176 kg milk. and 5.5 kg fat per year from 1979-87. The genetic level of daughters of young sires born after 1983 was equivalent or exceeded the genetic level of cows from other sires in the herd. Results indicated that within herd genetic improvement will not be hurt and may actually be enhanced from participating in a young sire sampling program depending upon sire selection of cows not bred to young sires. Herd characteristics explained forty-five and fifty-one percent of the differences in within herd genetic trends for milk and fat yield, respectively. Average sire PTA of non-first crop daughters accounted for 80% and 67% of the explainable differences. Other herd characteristics indicated that herds with larger within herd standard deviation milk yields, larger number of young sires represented, younger cows, less average days open, and greater percentage of cows sired by AI sires made faster rates of genetic improvement.
Ph. D.

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14

Mehta, Paras. "Asymptotic post-buckling analysis by Koiter's method with a general purpose finite element code." Thesis, This resource online, 1990. http://scholar.lib.vt.edu/theses/available/etd-06082009-170924/.

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15

Meyers, Carol Ann. "Thermal buckling and postbuckling of symmetrically laminated composite plates." Thesis, Virginia Tech, 1990. http://hdl.handle.net/10919/42238.

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This paper discusses an investigation into thermal buckling and post-buckling of symmetrically laminated composite plates. In this study, thermal buckling is investigated for laminates under two different simple support conditions, fixed and sliding. These laminates are subjected to the conditions of a uniform temperature change and a linearly varying temperature change along the length of the plate. Postbuckling in the presence of a uniform temperature change and nonlinear response to imperfections in the form of a thermal gradient through the thickness of the plate and a lack of initial flatness are also studied. The buckling response is studied using variational methods, specifically the Trefftz criterion. Postbuckling and responses to imperfections are studied using nonlinear equilibrium conditions. A Rayleigh-Ritz formulation is used to obtain numerical results from the formulations for the prebuckling response, the buckling response, and the post-buckling and imperfection responses. The analyses are applied to graphite-reinforced materials with (± 45/0₂)_s and (± 45/0/90)_s lamination sequences. Numerical results are obtained for these laminates and also for the case of these laminates being rotated 30° inplane. For the first laminate, for example, such a rotation results in a (+75/ — 15/30₂)_s. stacking sequence. Such skewing of the principal material directions may be encountered when using fiber-reinforced materials in a structurally tailored design. In addition, the influence on thermal buckling of a lack of ideal boundary conditions in the form of boundary compliance and thermal expansion, which would occur in any real set-up, are investigated.
Master of Science

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16

McDowell, Christine L. 1950. "Right hemisphere decline in the perception of emotion as a function of aging." Diss., Virginia Tech, 1991. http://hdl.handle.net/10919/39771.

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17

Meekins, Brian J. "Electronic monitoring in corrections: a proposed application of social bond theory." Thesis, Virginia Tech, 1996. http://hdl.handle.net/10919/44967.

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In recent years, harsher sentences have been pursued in criminal offenses leading to an increase in the use of incarceration. Prisons, largely unable to keep up with this demand, have become overcrowded in most areas. In response to prison overcrowding, some jurisdictions have begun to experiment with electronically monitored house arrest. This thesis is composed of a literature review and proposed study of recidivism in electronic monitoring (EM) programs. The literature review is composed of a general review of the history of corrections, a review of literature on electronic monitoring programs and social bond theory. The history of corrections serves to partially explain the emergence of electronic monitoring programs as an outcome of the adoption and failure of other forms of intermediate sanctions. The present state of electronic monitoring, including a description of the technology incorporated in these programs, the extent to which EM programs are implemented, and their cost effectiveness are discussed. In addition, some legal implications of its use are discussed. A review of previous research indicates numerous gaps in the existing evaluation of electronic monitoring programs. Because of these gaps many research questions are not sufficiently answered by the literature review. The rate of recidivism for EM programs compared to that of other correctional programs remains unclear. The underlying factors that affect the recidivism rate for EM programs also remains unclear. In addition, the effects on the offender, the offender’s family, peer group, and employment are not identified. The two reasons responsible for the inability of previous studies to adequately assess the rate of recidivism for EM programs compared to standard probation of parole and the underlying factors predicting recidivism are the exclusion of variables pertaining to the effects of electronic monitoring on the offender as well as the lack of theory needed to understand the relationships of recidivism, and type or correctional program. Literature on social bond theory is reviewed in order to provide theory to the examination of recidivism in electronic monitoring programs. Beginning with an explanation of Hirschi’s original work (1969), the review extends to empirical literature on the social bond. Finding this literature to be strongly supportive of social bond theory, it is adopted as a structure to examine recidivism. Primarily used in the study of delinquency, social bond theory is adapted to apply to the study of adult populations and recidivism, and the possible effects of EM on the social bond is discussed. A proposed research study is then presented examining the effects of EM on social bond factors and subsequently recidivism. The relevance of control variables, including length of sentence, type of offense, and prior convictions are discussed as well as the measurement of variables related to social bond theory. A structural equation model is developed that incorporates the control variables, bond variables, program variables, and recidivism, allowing for a simultaneous estimation of their relationships, using LISREL 8. It is hypothesized that EM programs, more than standard probation and parole positively affect the social bond of an offender to his or her family, peer group, and employment. In addition, it is believed that a stronger social bond to the institutions of family, peer group, and employment results in a lower incidence of recidivism.
Master of Science

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18

McGrory, William Dandridge. "Generalized spatial discretization techniques for space-marching algorithms." Diss., Virginia Tech, 1991. http://hdl.handle.net/10919/37228.

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19

McHerron, Dale C. "Creation and modification of polymeric materials using electron beam radiation." Diss., Virginia Tech, 1991. http://hdl.handle.net/10919/39936.

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20

McHenry, John T. "Multicomputer networks for smart structures." Diss., Virginia Tech, 1993. http://hdl.handle.net/10919/40053.

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21

Megivern, Monica M. "The development and field testing of an instrument to measure middle school counselors' knowledge of stepchildren." Diss., Virginia Polytechnic Institute and State University, 1990. http://hdl.handle.net/10919/80025.

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School counselors are in a position to receive referrals concerning children's reactions to changing family structures and to help a stepchild adjust to stepfamily living. This study assessed the need for training and education of Virginia middle school counselors regarding their knowledge about counseling stepchildren. This was done by measuring their level of knowledge through the development and use of the instrument, Knowledge and Skills for Counseling Stepchildren: A Self Assessment (KSCS). The focus of this study was the development and refinement of the KSCS. The purpose of the instrument was to assess the training needs of middle school counselors' knowledge about counseling stepchildren. The development of the KSCS took place through conducting item analyses on two pilot studies. Results of the study established a profile of middle school counselors past preparation, current strengths and deficiencies, and the need for training in the area of counseling stepchildren. The majority of counselors had done no prior reading or taken any coursework on the counseling of stepchildren. Test scores on the KSCS were negatively skewed, reflecting a low level of knowledge and identifying a need for training and education in this area. The majority of counselors came from schools where enrollment was 501 to 1,000 and 30% of their caseloads were stepchildren. Counselors from schools where enrollment was 0 to 500 and over 1,000 had caseloads where stepchildren also represented one-third of the students counseled, indicating a consistently high population of stepchildren. The majority of counselors offered no psychological or educational counseling program specifically for stepchildren. Six counselors offered a program specifically for stepchildren and 15 offered time-limited groups for children with separated or divorced parents that addressed issues pertinent to stepfamily living. Recommendations include revisions to the KSCS and required coursework on the counseling of stepchildren for state certification of school counselors.
Ed. D.

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22

Toccafondi, Toni L. "The application of Strumpel's behavioral economic model to explain financial behavior." Thesis, This resource online, 1991. http://scholar.lib.vt.edu/theses/available/etd-10242009-020306/.

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23

McDougal, Leigh Ann. "Wild turkey-road interactions on a Virginia national forest." Thesis, Virginia Tech, 1990. http://hdl.handle.net/10919/42078.

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I studied wild turkey (Meleagris gallopavo) movements and range use in response to roads and vehicular road use on the George Washington National Forest, Virginia. Radio-equipped wild turkeys used areas within 150 m of state roads less than expected and areas > 450m from ail roads greater than expected. Turkeys were observed to cross state roads only in locations where the roads were bordered by woods or fields less than 80 m wide. Seasonal habitat preferences, rather than vehicular road use levels, seemed to dictate turkey use of the area surrounding Forest Service roads. Revegetated Forest Service roads were preferred habitat in the spring and summer. Turkey mortality was not closely related to road type or road use levels.
Master of Science

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24

Menon, Hari. "Improving the general measurement methodology." Thesis, Virginia Tech, 1990. http://hdl.handle.net/10919/41584.

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This thesis proposed to improve an existing performance measurement methodology called the "General Measurement Methodology (GMM)." The GMM as well as its variations have been used in organizations to design a measurement effort to support performance improvement. It has evolved over a number of years and is currently being researched at the International Productivity Center (IPC). In order to attain its objective, this research adopted a case study approach supported by data from the literature as well as an expert panel. Three cases were considered to collect data on performance measurement system design and implementation. Two of these organizations (IPC and Acme Manufacturing Company) have used the GMM to set up performance measurement systems. The third case study (Golden State Power and Light {GSP&L}) was selected to lend another perspective to measurement system design since it used another approach or methodology. Site visits were made to each case study and data was collected primarily using the unstructured interview. The literature contributed more perspectives on how organizations measure performance. Responses from an expert panel of fourteen people enhanced the data base even further. Data from each of the above sources have been collected and processed. As explained in Chapter 6, the research design adopted had to be altered toward the end since the development and validation of the improved GMM was difficult. The strength and advantages of the improved version could not be completely verified. However, the conclusions of this thesis include a comprehensive description of the knowledge, wisdom and insight gained about measurement. A roadmap (based on the information acquired) toward effective measurement system design, development and implementation has also been presented.
Master of Science

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25

Zeng, Ka. "U.S. policy of conditioning China's most-favored-nation status on intellectual property protection, 1991-1993." Thesis, This resource online, 1995. http://scholar.lib.vt.edu/theses/available/etd-01102009-063924/.

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26

Yang, Lifeng. "A microprocessor based bus relay." Thesis, Virginia Tech, 1991. http://hdl.handle.net/10919/41506.

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A microprocessor based bus protection scheme has been proposed for a single bus system which employs a new technique to overcome the problem of current transformer saturation. The protection scheme uses a combination of the percentage differential current principle and the phase comparison principle. A sampling rate of 1440 Hz is used. Existing algorithms for a saturation detector are reviewed and a new saturation detector has been developed. This new saturation detector employs the slope difference of the secondary current to determine the CT state. It has a high sensitivity and can reveal early (one-eighth cycle) saturation. With the incorporation of this new saturation detector, the bus relay can make a correct decision for either an internal or an external fault in the presence of current transformer saturation in a half cycle in most cases. The bus protection scheme has been coded in Fortran and tested against data produced from EMTP. The simulated results from eight sets of data are presented in this thesis. All cases show that the bus protection scheme works correctly. The algorithm for the new saturation detector will be implemented using a 32-bit microprocessor by Mr. Paul A. Dolloff.
Master of Science

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27

Yang, Jae-Guen. "Lateral bracing forces in compressed two-span columns with initial curvature." Thesis, Virginia Tech, 1991. http://hdl.handle.net/10919/41515.

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The main purpose of this study is to find critical loads and full bracing conditions for perfect two-span columns, and to find the reaction forces at the lateral bracing supports and maximum deflections for two-span columns with initial curvature. In each case, the column under consideration may have different bending stiffnesses in each span, and the column is subjected to an axial compressive load. The braces are not assumed to be equally spaced, and may have different spring stiffnesses. For the perfect columns, it is found that if the internal lateral support is located in the middle of the column , the column can resist a higher applied load than for any other support location. The load resisting capacity of the column depends on the lateral spring stiffness. It is also found that an ideal spring stiffness, corresponding to full bracing, only exists under special conditions. For the imperfect columns, the initial shape is assumed to be the same as the buckling mode of the perfect column, and its size is specified. It is found that there are no reaction forces when there is full bracing. The reaction forces and maximum deflections are proportional to the size of the initial deflection, so their values for initial deflections of the same shape but different size can be determined directly from the results presented here.
Master of Science

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28

Menelik, G. "Leaching and denitrification losses of nitrogen from corn fields as influenced by conventional- and no-till practices in soils of the Chesapeake Bay area." Diss., Virginia Tech, 1990. http://hdl.handle.net/10919/39944.

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29

Mehrotra, Neeta. "An automated method for locating sinkholes in Montgomery County, Virginia, using digital elevation models." Thesis, This resource online, 1992. http://scholar.lib.vt.edu/theses/available/etd-08222009-040435/.

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30

Meehan, Amy L. "Impacts of group selection harvest openings on the reproductive success of the Solitary Vireo (Vireo solitarius alticola)." Thesis, Virginia Tech, 1996. http://hdl.handle.net/10919/44965.

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Solitary Vireos (Vireo solitarius alticola) were studied on an extensive mature forest landscape in 1994 and on three sites harvested using the group selection method in 1995. Pairing success was 88% on the unharvested site in 1994, however it was lower on the harvested sites in 1995 (53.8%). Low reproductive success was observed in both years (12% and 22% respectively). In 1995, the amount of opening within a 200 meter radius of the first observation point of a male was positively related to pairing success (p<0.05). This suggests that females may be cueing in on the increased number of shrubs in and around openings.
Master of Science

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31

Warrington, Thomas Joseph. "Experiments and simulations of large-angle flexible beam control using an adaptive truss." Thesis, This resource online, 1991. http://scholar.lib.vt.edu/theses/available/etd-03032009-040343/.

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32

Cooper, Sharon Edie. "Study of the miscibility, morphology, crystallization, and melting behavior of blends of poly(3-hydroxybutyrate) and poly(vinylidene fluoride)." Thesis, This resource online, 1991. http://scholar.lib.vt.edu/theses/available/etd-11242009-020034/.

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33

Galagedera, Nandadeva Lalith. "Integrity and effectiveness of standard preformed membranes placed on concrete bridge decks." Thesis, Virginia Tech, 1991. http://hdl.handle.net/10919/42152.

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Waterproofing membranes have been used on bridge decks for almost three decades in order to prevent chloride ingress into concrete. However, the performance of these membranes have yet to be adequately evaluated. Therefore, this research was carried out primarily to evaluate the integrity and effectiveness of standard preformed membranes placed on concrete bridge decks.

The actual conditions of a bridge deck were simulated in the laboratory using scaled-down reinforced concrete specimens. Forty-eight outdoor and twelve indoor specimens were cast. Three types of standard preformed membranes (Bithuthene 5000, Royston lOA, and Protecto Wrap M400-A), punctured with holes of various sizes and frequencies per unit area, were placed on the specim~ns. All of the specimens were overlaid with 2.5 inches of hot-mix asphalt, except four outdoor (control) specimens and three indoor specimens.

Master of Science

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34

Johnsson, Erik L. "The use of chemiluminescence for detection of ignition, temperature, and fuel-to-air ratio of flames." Thesis, Virginia Tech, 1991. http://hdl.handle.net/10919/42410.

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A fast response method for detection of ignition and extinction of liquid spray flames has been improved. Also, a method of determining fuel-to-air ratios and temperatures of pre-mixed, gaseous flames has been developed. Both methods utilize chemiluminescent signals from an OH system centered at 309 nm and a CH system centered at 431 nm. The ignition and extinction method was improved by replacing an optical system composed of lenses and a monochromator by a system composed of a fiber optic cable and band pass interference filters. The use of a solid-state photodiode instead of a photomultiplier tube was investigated. Transient histories of the OH and CH signals were recorded by performing light-off ignition and intermittent ignition flame tests. These signal histories were compared to histories obtained using the original apparatus. The fuel-to-air ratio and temperature detection method was investigated by recording the spectra of laminar, pre-mixed methane flames of known stoichiometry with a lens, monochromator, and photomultiplier tube set-up and measuring the flame temperatures with a high-temperature Pt-10%Rh thermocouple. Various combinations of signal characteristics were found to be functions of fuel-to-air ratio and temperature. Optimum signals for monitoring with a detector were determined. Recommendations for future work in this area are discussed.
Master of Science

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35

Johnson, David Page. "A study of tension, compression, and shear test methods for advanced composites." Thesis, Virginia Tech, 1991. http://hdl.handle.net/10919/42129.

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A study of the literature pertaining to test methods for advanced composite materials has been carried out. Several test methods were discussed and compared for each of three areas of interest. These areas were uniaxial tension, uniaxial compression and in-plane shear. Test methods were selected for tension, compression and shear and guidelines set for the entry of material property data into a comprehensive mechanical property database being undertaken by Virginia Tech's Center for Composite Materials and Structures (CCMS). According to the findings, recommendations for future work were made.
Master of Science

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36

Hopper, Robert Huston. "Composite circular braid mechanics." Thesis, Virginia Tech, 1991. http://hdl.handle.net/10919/42138.

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Braided composites find many diverse applications in modern technology and tailoring the mechanical properties of these structures has become increasingly important. This thesis will examine one class of circular braids encompassing an elastic core. By hypothesizing four modes of operation and incorporating primary influences, the mechanical response of the composite is predicted based on its initial parameters and material properties. The ability to model the yarns that constitute the braid as nonlinear materials enables the simulated response to span finite deformations. A scheme for nondimensionalizing the model parameters and governing equations for each mode of operation is also proposed and implemented.

In an effort to validate the assumptions underlying the model's formulation, a series of experimental trials are documented that verify the fundamental braid mechanics. A wide variety of analytical cases are also introduced to investigate the influences of various model parameters. Possible extensions for the existing model are also noted.
Master of Science

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37

Kean, Van Alexander. "The Petroleum Disruption Response System." Thesis, Virginia Tech, 1991. http://hdl.handle.net/10919/41502.

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The petroleum disruptions experienced in 1973 and 1979 demonstrated to the Department of Defense (DoD) that, for numerous reasons, the normal support for DoD requirements could rapidly deteriorate. Crude oil shortages caused DoD's historical supplier to prorate or completely cease deliveries under existing contracts, and it became difficult for the Defense Fuel Supply Center (DFSC) to secure replacement or follow-on contracts for fuels. In order to sustain necessary peacetime activities, the services were forced to dip into the war reserves. The effect was a decrease in the wartime sustainability of our forces until the war reserves were reconstituted.

As a result of DoD "Supply Assurance" initiatives prompted by the 1979 disruption, numerous policy options have been developed to help the Office of the Secretary of Defense (OSD) more effectively deal with future shortage situations. The key to avoiding the problems of 1973 and 1979 is early identification of shortage situations and selection of appropriate policy options designed to ensure a steady supply of military fuels during energy emergencies.

The Petroleum Disruption Response System (PDRS) is a decision support system designed to assist DFSC energy analysts and planners in preparing recommendations for the Office of the Assistant Secretary of Defense (OASD) energy policy staff on appropriate policy options to ensure adequate petroleum supplies for the national defense.

This paper contains a conceptual model of PDRS that is based on a network optimization distribution model. The model would optimize the resupply distribution network in terms of minimum cost solution.
Master of Science

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38

Cowgill, Marc C. "Behavioral specificity and reliability in job analysis and job specification." Thesis, Virginia Tech, 1991. http://hdl.handle.net/10919/44141.

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Job analysis, narrowly defined, refers to the collection of data describing job-related behaviors and the characteristics of the job environment. Job specification refers to the process of inferring required traits or abilities necessary for a desired level of job performance. Differences in the judgmental processes involved in these two functions were explored by (a) investigating the potential schema- or stereotype-based nature of job specification ratings, and (b) assessing the relationship between behavioral specificity and interrater reliability. These concerns were investigated through the use of 3 groups of subject raters: one group possessing extensive job knowledge, one group possessing some degree of job familiarity, and one group possessing little or no job knowledge. All subjects completed a job analysis instrument (the Job Element Inventory) and a job specification instrument (the Threshold Traits Analysis; TTA). Contrary to predictions, little evidence was uncovered to suggest extensive schema-usage on the part of TTA raters. In addition, the 2 instruments achieved similar levels of interrater reliability among the 3 subject groups. However, marginal support was found for the notion that behaviorally specific items generate higher reliability the less-specific items, and in replication of previous findings, job-naive raters were found unable to achieve the reliability of subject matter experts. Suggestions for future research are offered.
Master of Science

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39

Hendricks, David Gerard. "The experimental determination of rotor blade dynamic bending moments of a 10-kw wind turbine." Thesis, Virginia Tech, 1991. http://hdl.handle.net/10919/42128.

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A l0-kW horizontal axis wind turbine was studied to determine the effects of wind shear and gravity on rotor blade bending moments.

A drag sphere based wind measuring system was designed to measure rapid fluctuations in wind velocity at two different heights. However, severe power line noise problems with the low level signals forced the use of standard rotating cup anemometry.

Rotor blade bending moments were obtained with strain gages mounted on blade extenders near the root of the instrumented blade. Rotor angular position data were obtained with a photocell arrangement.

The one per revolution primary bending moment frequency was caused mostly by gravity-induced bending. Also present is the 6 Hz blade natural frequency. A logarithmic atmospheric boundary layer (ABL) profile was used to estimate wind conditions at the upper level. Examination of the bending moment data revealed good agreement with values predicted from the ABL profile (within 4% in the mean) indicating the profile was a good mean approximation.

A logarithmic atmospheric boundary layer (ABL) profile was used to estimate wind conditions at the upper level. Examination of the bending moment data revealed good agreement with values predicted from the ABL profile (within 4% in the mean) indicating the profile was a good mean approximation.
Master of Science

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40

Beckwith, Diane Duncan. "Characterization of juvenility and photoperiodic responses of Rudbeckia hirta originating from different latitudes." Thesis, Virginia Tech, 1991. http://hdl.handle.net/10919/45987.

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Rudbeckia hirta is a tender perennial or self-sowing annual which is becoming increasingly popular as a garden flower and a component of wildflower meadow mixes. It may also have -considerable potential for use as a potted crop. R. hirta has a defined juvenility period but preliminary unpublished results suggested that plants originating from different latitudes may possess unequal juvenile periods and exhibit dissimilar sensitivities to photoperiod. Seven R. hirta ecotypes originating from latitudes ranging from 30.l0oN to 45.l0oN were exposed to long days (LD) at different leaf numbers to determine juvenile phase length and speed of floral initiation. Ecotypes from northern latitudes had fewer leaves at maturity and, overall, there was a quadratic relationship between latitude of origin and number of days to first flower from start of LD. Once plants were mature, the speed of floral initiation and development also varied among ecotypes.
Master of Science

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41

Kothari, Rajiv D. "Experimental results on aliasing errors in circular BIST design." Thesis, Virginia Tech, 1991. http://hdl.handle.net/10919/42137.

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Abstract:

The circular BIST design is a technique in which the existing circuit is modified, so that the processes of test generation and response compaction are carried out by the circuit being tested itself. Most response compaction techniques suffer from loss of information, known as aliasing. Aliasing is said to occur in a response compaction technique when the response generated by the circuit, under the presence of a fault, is different from its fault-free response, but this information is later lost during compaction, and the faulty compacted response at the end of the test session is identical to the fault-free compacted response.

A program to synthesize circular BIST hardware on general sequential circuits has been developed. A parallel fault simulator has been developed to detect aliasing errors in circular BIST design. Experimental results on aliasing probability in circular BIST design are reported for twenty-three sequential benchmark circuits.

Master of Science

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42

Schell, Tim. "The effects of feeding aflatoxin contaminated swine diets with clays on performance, mineral metabolism, immune response and liver function in weanling and growing Pigs." Thesis, Virginia Tech, 1991. http://hdl.handle.net/10919/41317.

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43

Wirt, Donald Lee. "Bracing requirements for post-frame endwalls." Thesis, Virginia Tech, 1991. http://hdl.handle.net/10919/41510.

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When diaphragm action is considered in the design of post-frame buildings, the endwalls may require supplemental reinforcement to replace lost strength and stiffness, due to placement of large doors and openings in the endwalls. The diaphragm design standard, ASAE EP484, does not provide guidelines concerning such endwall reinforcement. Flat steel strapping 1s proposed for use as supplemental reinforcement to replace this lost strength and stiffness. An analysis procedure was developed, with the intention of serving as input to endwall diaphragm design. Using PPSA 3.00 and calibrated endwall data, a computer structural analog was developed that “mimics” the deflection of an actual solid endwall. Sections of the structural analog were removed to represent a centered door opening. Fictitious members representing steel-strap bracing were added to the remaining endwall diaphragm to restore the endwall deflection to that of the same endwall with no door openings. Large corner post uplift values were observed for tall endwalls. For purposes of endwall analysis, it is necessary to distribute corner post uplift forces to the other posts along the adjacent endwall and sidewall. Along with the tabulated results in this research, this analysis procedure provides building designers a tool that will enable them to analyze virtually any endwall-door combination. All that is required is PPSA 3.00 software (or equivalent), a personal computer, and endwall stiffness data.
Master of Science

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44

Anderson, Bennett B. "Standing seam roof system strength under uplift loading." Thesis, This resource online, 1991. http://scholar.lib.vt.edu/theses/available/etd-08182009-040252/.

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45

Hume, Lily Ann. "The dissolution rate of chrysotile." Thesis, This resource online, 1991. http://scholar.lib.vt.edu/theses/available/etd-06082009-171119/.

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46

Clifton, Mary Jennifer. "Studies in stereoselective synthesis via reissert compound chemistry." Thesis, This resource online, 1991. http://scholar.lib.vt.edu/theses/available/etd-08222009-040256/.

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47

Lacy, David Terrell. "An automated methodology for dynamic force analysis of adaptive spatial trusses." Thesis, This resource online, 1991. http://scholar.lib.vt.edu/theses/available/etd-11072008-063632/.

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48

Gorbea, Carlos M. "Glycolipids in mouse F9 teratocarcinoma cells : some changes associated with retinoic acid-induced differentiation /." Thesis, This resource online, 1991. http://scholar.lib.vt.edu/theses/available/etd-08142009-040425/.

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49

Lansey, Christopher A. "Analytical and experimental analysis of fireplace performance." Thesis, This resource online, 1991. http://scholar.lib.vt.edu/theses/available/etd-11072008-063033/.

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50

Putz, James M. "Development of a direct-force-reading, thin-film shear stress gage." Thesis, This resource online, 1991. http://scholar.lib.vt.edu/theses/available/etd-10102009-020143/.

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