Wastewater effluents from two absorption systems were studied in the Assateague Island National Seashore Park, during 1993. The study focused on the wastewater effluents from a mound and a conventional on-site wastewater disposal system (OSWDS). The site was characterized by coastal beach soils. Average wastewater loadings to each drainfield were 10,800 liters per day. The density of the ground water varied due to changes in salinity and the hydraulic gradients fluctuated due to tidal effects. The OSWDS’s were used between four to five months of the year, with three to four months at near full capacity. Dissolved inorganic nitrogen (DIN) and dissolved inorganic phosphorus (DIP) immediately adjacent to the conventional drainfield were correlated with bath house usage. The average DIN concentration was 0.76 mg/L in January-March, before the season started, increased to 80.78 mg/L by August, and decreased to 26.41 mg/L in October-November, once the season ended. Likewise the DIP increased from 1.20 mg/L before the season started, to 7.36 mg/L during the season, and decreased to 1.86 mg/L once the season ended. Conversely, the DIN and DIP in the ground water immediately adjacent to the mound drainfield were not well correlated with bath house usage. The DIN increased from 1.01 mg/L during off-season, to 39.95 mg/L during September and showed almost no appreciable difference after fall closure. The DIP did not show a significant difference from off-season values, with an average value of 0.29 mg/L. Transport of the wastewater through the ground water toward the surface waters was suggested by increasing DIN concentrations with distance from both drainfields over time with increasing bath house usage. Elevated <i>Escherichia coli</i> concentrations were measured in the ground water immediately adjacent to the conventional drainfield. Concentrations of <i>E. coli</i> ≥ 16,000 MPN/100 ml were measured up to 2 meters from this drainfield. On the other hand, the mound did not show, on average, ground water fecal contamination. There was no indication of fecal coliform contamination to the ocean waters in either site. On only three occasions were <i>E. coli</i> concentrations, with values between 30 and 130 MPN/100 ml measured at distances greater than 40 meters from the conventional drainfield. At the mound site on only one occasion was a E. coli concentration with a value of 23 MPN/100 ml measured at distance of 50 meters from the drainfield. The conclusions from this study were: 1) the mound drainfield had a better performance in wastewater treatment than the conventional drainfield, 2) direct transport of <i>E. coli</i> to surface water via ground water could not be detected or measured, 3) both systems showed direct loadings of nutrients to the ground water, 4) there was some evidence of nutrient transport to surface waters, and 5) the conventional system showed high loadings of <i>E. coli</i> to ground water. / Master of Science

The present study examines the relationship of perceived coaching behavior, team cohesion, and performance in different types of sport. It also looks at the development of cohesion over time and if it is affected by other variables. Coaching behavior was defined using Chelladurai’s (1978) Multidimensional model of leadership, and team cohesion is defined using Widmeyer’s et al. (1985) Conceptual Model of Cohesion. This examination was done using high school soccer and baseball teams. It was determined that the coaches for the baseball and soccer teams rated highest in training and instruction, and positive feedback. For this reason, an analysis of leadership between the sports was not possible. A MANOVA was carried out to determine if time and other variables of leadership, team differences, and sport differences played a role in the development of cohesion. Time had no significant effect on cohesion, and there was just a moderate effect on team differences in individual attraction to group-task and social. Logistic regression revealed that soccer teams who were more successful tended to have higher cohesion as opposed to baseball teams who were more successful tended to have lower cohesion. This demonstrated the differences between baseball and soccer in which soccer is a more interactive sport and requires greater cooperation and coordination to be successful. / Master of Science

Formulate a Thesis question that generates enough resistance in order to begin to identify and define a way of working. To maintain a constant dialogue between a decision, reflected upon as the result of a method of evaluation, and the method itself. / Master of Architecture

Wideband electromagnetic characterization of Portland cement concrete (PCC) has been investigated in this study. This is necessary to correlate the material properties of PCC with its physical condition and hence aid in nondestructive evaluation of practical PCC structures. A test fixture has been designed to characterize PCC test specimens in the frequency range of 100-1000 MHz. Measurements have been performed in both time domain and frequency domain. The focus of this research has been to investigate time domain techniques for the characterization of PCC specimens under different test conditions. A simplified TDR measurement technique using one-port calibration scheme has been proposed for the research. Measurements have been carried on reference materials (e.g. Teflon) to verify the accuracy of the proposed technique. Extensive calibration and de-embedding have been studied to minimize the systematic errors involved in the measurement process. A computer simulation based verification process has been studied to validate the proposed calibration and de-embedding scheme. Sensitivity analysis and study of repeatability of the measurement process has been done as well. / Master of Science

A study was conducted to investigate the effectiveness of different instructional tools for teaching individuals to calculate a protected hearing level given A- or C-weighted sound levels, and using the NRR and HML methods. Three instructional tools were evaluated: 1) outline instructions, 2) tabular nomogram, and 3) hypermedia computer-based instructions. Effectiveness was measured in terms of calculation time and proportion of errors made. The results yielded no statistically-significant differences between the tools. All subjects performed equally well using each tool for the NRR method, and equally poor using each tool for the HML method. Two additional topics of investigation included a baseline of knowledge determination for hearing conservationists, and an inquiry into the subjective discrimination of various sound spectra. The baseline of knowledge determination evaluated the ability of subjects to calculate a protected hearing level, given A- and/or C-weighted sound levels and the NRR. Since professionals in this field are responsible for determining OSHA compliance, this test should have resulted in high baseline scores. However, only 50% of the subjects could calculate a correct answer given the C-weighted sound level; only 17% could calculate a correct answer given the A-weighted level. The spectral discrimination portion of the study evaluated the ability of an individual to subjectively classify noises as high frequency-dominated, or low-frequency-dominated. Of the 12 pink and industrial noises used, only three could be correctly identified more than 90% of the time. This suggests that subjective classifications of noises should not be relied upon. / Master of Science

Polymer chemistry has primarily been a main chain carbon-based science, but recently the usage of inorganic polymeric materials has increased with polyphosphazene research leading the way. The credit for the increased interest in the field of phosphazene chemistry arises from the unique physical properties these materials possess. Depending upon the rigidity of the side group, the morphology of these materials is controllable. A high degree of chain mobility is exhibited by this class of polymers resulting in low glass transitions. The industrial applications of these materials are quite divergent as a result of the various morphologies and glass transitions. Possible sealant applications of these materials are apparent and have yet to be realized. These will be the focus of this thesis. The objective of this research was to characterize polyphenoxy-ethylphenoxy-phosphazene in terms of three bulk properties to determine the possibility of favorable sealant application. Investigation of the solubility parameter through solvent ingression experiments determined the solvent resistive abilities of the material. Thermogravimetric analysis set an upper temperature limit of application by determining the thermal stability of the polymer. The study of polyphenoxy-ethylphenoxy-phospazene through dynamic mechanical analysis provided insight into the vibrational damping characteristics of the material as well as establishing a lower temperature limit of possible use. Combination of the results from these various experiments enables one to make qualitative conclusions regarding favorable sealant application. / Master of Science

In this thesis I explore the following question: When a government agency is charged with implementing policies formulated in the light of scientific principles, why do the justifications for implementation differ from justifications for the legislation? The predator reintroduction being carried out under the Northern Rocky Mountain Wolf Recovery Plan, now 19 years old, has recently catalyzed a national controversy about the value of wildlife. My goal is to examine the reasons why the ecological values that infuse government policy play little part in governmental justifications for policy implementation. / Master of Science

A model is developed for predicting power losses for a hard-switching threephase IGBT inverter drive for synchronous motor applications. For a given set of motor parameters, semiconductor device parameters and motor operating conditions, the various losses and the temperature rises of semiconductor junction can be predicted. All parameter values, semiconductor or motor, required to predict the losses are readily available from manufacturer's data sheet. Using this model, a number of IGBTs were evaluated for the suitability of synchronous motor applications. Conclusions of this evaluation are presented in the thesis. The model has been verified experimentally using both electrical power measurement and thermal measurement. / Master of Science

This study examines the current retirement strategies of agricultural producers, determines farmers’ levels of investment and financial planning knowledge, and makes recommendations for the construction of a computer-based expert system to assist producers in developing retirement plans and strategies. The first two objectives are accomplished through the analysis of 336 self-administered and mailed surveys from producers in Iowa, Kansas, Nebraska, Virginia, and Washington. The third objective is completed utilizing study results, information provided by individuals knowledgeable m personal finance, and literature dealing with personal financial management. Seventy percent of the survey respondents invest in non-farm assets. Farmers who do not invest off the farm cite a desire to pay down debt, little or no funds available, tax savings, and liquidity as their leading reasons not to invest off the farm, while those who do invest off-farm list tax benefits and diversification as their leading motivators. Respondents began retirement saving early and one-third of them wanted to begin withdrawing from the farming operation by the age of 60. Seventy-eight percent of the respondents with non-farm jobs invest in assets off the farm (p < .05). Producers with the highest levels of formal education are more likely to invest off the farm than the less educated producers (p < .005). Farmers with less formal education tend to delay investing for retirement until later in life (p < .001). / Master of Science

Increased breast cancer mortality among socio-economically disadvantaged women is well documented. Also well documented is the utility of BSE as an economical means of early detection and, therefore, decreased breast cancer mortality. This study assessed health beliefs and breast cancer screening practices among a sample of women recruited from local public health clinics as well as a sample of women recruited from a federally-subsidized housing development in Roanoke, Virginia. In addition, this study concomitantly examined the efficacy of an intervention promoting BSE through standard face-to-face training, written prompts, self-management, and personalized feedback within the housing development sample. The feasibility of recruiting and intervening with predominately minority, low SES, women living in public housing is also addressed. The clinic sample consisted of 42 women who ranged in age from 20 to 44 (X=24.9 years), 88.1% had earned their high school diploma or equivalency, and the sample was predominantly (83.3%) Caucasian. The housing sample (n=30) was largely African-American (87%), ranged in age from 20 to 57 (X=35 years), and had a mean educational attainment of 11th grade. Both samples reported relatively low levels of BSE frequency, quality, and knowledge; however, the clinic sample was significantly more likely to have tried a BSE than women in the housing sample (p < .05) and reported a significantly higher perception of benefits of BSE (p < .001). Analyses of variance revealed a significant effect of the intervention on BSE frequency (p < .05), although not on BSE quality or knowledge. Results of stepwise multiple regressions varied depending on the dependent measure used for BSE frequency; however, number of project-initiated contacts uniformly appeared as a significant predictor of BSE frequency whereas knowledge was the largest significant predictor of BSE quality. The study demonstrated the potential utility of the intervention to promote the adoption of BSE; however, BSE proficiency must also be addressed for the intervention to succeed in achieving health benefits. / Master of Science