Methods have been developed to solve the problem of laminar boundary layers on sharp and spherically blunt cones at angle of attack to nonuniform supersonic free streams. A three-dimensional boundary-layer solution is used to solve sharp cone problems and the afterbody of blunt cone problems. An axisymmetric boundary layer solution is used to solve the axisymmetric region of blunt cones. An interpolation method has been developed enabling the use of axisymmetric solution data as starting data for the three dimensional boundary layer solution on a blunt cone. An existing implicit finite-difference numerical scheme was used to solve both the axisymmetric and three-dimensional boundary-layer equations. Edge properties for a sharp cone and for the afterbody of a blunt cone come from method of characteristics solutions of the inviscid flow field. A modified inverse method for solving the inviscid flow field is used to provide edge properties for the axisymmetric region of blunt cones. Results obtained for blunt cones in uniform flow are compared to experimental data with. good agreement. Uniform flow results for sharp cones are compared to experimental data and to existing numerical data. Skin friction and heat transfer data obtained for sharp and blunt cones in nonuniform flow fields show a departure from the uniform flow values. Normalized skin friction and heat transfer coefficients for a sharp cone in two dimensional shear flow increase downstream relative to conical flow values. The effect of wake flow on a blunt cone is to increase the heat transfer considerably, relative to uniform flow values. Downstream values of skin friction are shown to fall below uniform flow values. Decreasing the width of the wake causes more severe departure from uniform flow values, for both skin friction and heat transfer on blunt cones. The presence of free-stream nonuniformities hastened the onset of separation particularly in the blunt cone cases. The beginning of separation occurred sooner in both the longitudinal and transverse planes. Smaller width wakes and higher angles of attack caused earlier onset of separation. / Master of Science

A computer simulation model of the planning process of the wildlife management agency of an eastern sta te was constructed. The model is constructed in the form of a management game for inservice training and classroom use. The player of the game formulates a five-year operating plan for the mountainous region of the state. The plan is implemented on an annual basis and annual reports are issued to reflect how well scheduled activities. meet public demands. The player is allowed to modify the five-year operating plan after examination of the annual report. Components of the wildlife management system included in the model are: land acquisition, hunter access, habitat improvement, stocking programs, coordination with forestry practices, public relations, hunting regulations, and budget calculations. Public reaction to the planner's policies is provided on an annual basis in addition to output concerning mandays of hunting, population levels, estimates of legal and illegal harvest, and budget constraints for the following year. Verification of the model was based on subjective tests of reasonableness performed by those considered knowledgeable about the real system. Operational instructions are provided for those wishing to use the game and an example five-year run of the game is presented as a guide for use. / Master of Science

Insurance has been regulated in the United States since colonial times, albeit in many faces. This thesis summarizes the history of insurance regulation in the United States and Virginia. Special attention is given to the relationship among the insurance industry, the insurance regulator, and some aspects of the role of economic and political self interests in the development of insurance regulation. This paper also summarizes the various arguments involved in the state vs. federal controversy over regulatory control. The various methods and purposes of current rate regulation are also briefly discussed. Finally, some descriptive characteristics of insurance regulation in Virginia are presented and an empirical analysis of budget behavior of the Virginia Bureau of Insurance is offered. / Master of Arts

The need to redesign the outdoor play space and related equipment at the Virginia Polytechnic Institute and State University Laboratory School, in Blacksburg, Virginia, was investigated. Under the direction of the Department of Child Development, a rigid program was created which would determine the final design. The total design process is divided into three phases. The study of child behavior establishes a firm foundation for this thesis study. The construction of prototype playground equipment serves as a basis by which this researcher traces and records ‘ the children's play patterns. The complete synthesis of all the data collected is represented by the final solution for this new outdoor environment. A description of the investigation and the many factors which assisted in the determination of a final playground design and the final design is included. / Master of Science

A corrosion fatigue investigation was conducted on anodized 2024-T35l aluminum alloy in reversed torsion. The corrosive environment was provided by varying the relative humidity of air around the specimens during fatigue. The effect of water vapor on fatigue of aluminum (and alloys) have been previously established by other investigators. The aluminum oxide coating was grown on the metal substrate to two thicknesses (0.05 and 0.3 mils). One lot of specimens was polished to determine the effect of this type of surface finish. In all, a total of 108 specimens were run at various combinations of stress, relative humidity, coating thickness, surface finish (polishing), and coating. Six specimens were run at the stress levels of approximately 13,000, 17,000, and 20,000 lb/in² respectively. The three relative humidity ranges used were low (20-25%), medium (55-60%), and high (86-91%). Results of the investigation showed the anodized specimens at low relative humidity to have an increase in fatigue life over specimens of the same type tested at high relative humidity. The increases in fatigue lives were 281% and 194% for the 0.3 mil specimens at the highest and lowest stress levels. Increases in fatigue lives of 1112% and 338% were also found at the highest and medium stress levels for the 0.05 mil anodized specimens. It was found that the 0.3 mil anodized specimens in a relative humidity environment of 55-60% had no significant difference from those tested in an environment of 86-91%. The fatigue lives of the anodized specimens compared to results of unanodized specimens of a previous investigator at the low humidity range gave fatigue life increases of 514% and 174% at the high and low stress levels. Another comparison for anodized and unanodized specimens at high humidity showed no differences between the specimens fatigue lives. It is suggested that some phenomena is responsible for these unexpected results. That is, a humidity threshold appears to be necessary to penetrate the anodized barrier so that there is no protection of the substrate after reaching this threshold. The coating thickness of the oxide and the polishing of the specimens before anodizing showed no effect. The scatter in the investigation did not change with humidity, coating thickness, polishing or coating. / Master of Science

A 2 x 2 factorially designed experiment was conducted to study the effects of feeding two levels of calcium and phosphorus alone and in combination, on magnesium utilization in ruminants. Twelve wether lambs were used in two metabolism trials. The two levels of calcium were 0.4 and 1.4% and the two levels of phosphorus were 0.3 and 1.3%. Apparent magnesium absorption, expressed as percent of intake was lower for the high-calcium fed lambs (P< .05) and for the high-phosphorus fed lambs (P< .01). Urinary magnesium excretion was lower (P< .01) for the high-phosphorus fed lambs. Urinary calcium excretion was lower (P< .01) for the high-phosphorus fed lambs. Calcium retention was higher (P< .01) for the high-calcium fed lambs. Apparent phosphorus absorption, phosphorus retention and urinary phosphorus excretion were higher (P< .01) for the lambs fed the high-phosphorus level. Serum magnesium was lower (P< .01) and serum inorganic phosphorus was higher (P< .01) for the high-phosphorus fed lambs. Serum calcium was higher (P< .05) for the high-calcium fed lambs and lower (P< .01) for the lambs receiving the high-phosphorus rations. Apparent digestibility of ether extract, and dry matter content of the feces were higher (P< .05) for the lambs fed the high-calcium level and lower for the high-phosphorus fed lambs (P< .01). The significant (P< .01) interaction between calcium and phosphorus levels on dry matter of feces indicates that high dietary calcium was partially effective in reversing the detrimental effects of high-phosphorus level. / Master of Science

New mechanisms proposed for achieving intergovernmental cooperation, primarily among the four major cities. of the Southeastern Virginia Planning District, were evaluated relative to existing legislative provisions for the planning district to become a multi-purpose service district. Those new mechanisms included: an urban services corporation; a regional urban bank; a regional incentive fund; and an area-wide commission to oversee the other mechanisms. They were not acceptable to the state administration as presented in a consultants' report. In the evaluation, the mechanisms were found to be more appropriate to the needs of the region than the service district or proposed modifications to that concept. Recommendations were made aimed at achieving compromise mechanisms acceptable to the state and the region. / Master of Urban Affairs

Methazole-¹⁴C and/or its C-labeled metabolites moved acropetally in the treated leaves of cotton (Gossypium hirsutum L., 'Deltapine') and prickly sida (Sida spinosa L.). The mobility pattern was not altered with polysorbate surfactants with different HLB (Hydrophilic-Lipophilic Balance) values. Total uptake and distribution of ¹⁴C increased with increasing concentration of methanol as a solvent and decreasing HLB values of surfactants. More ¹⁴C was translocated in cotton than in prickly sida. The effects of surfactants were masked by the drastic solvent action of 100% methanol. When the solvent effect was subtracted, the surfactant with HLB 8 caused greatest enhancement of translocation of ¹⁴C in both species. Scanning electron photomicrographs showed that polysorbate surfactant (HLB 4.3) eroded cotton leaf surfaces severely at the 1% (w/w) level. Reticulated and etched patterns were observed on cotton leaf surfaces treated with water soluble surfactants. Trichomes on the leaves of prickly sida appeared not to be affected by the surfactants. The leaves of prickly sida were less affected than those of cotton by the surfactants. Surface deposits of formulated methazole were different in appearance from those of technical methazole. The influence of polysorbate surfactants on the leaching of methazole-¹⁴C in Landisburg-Greendale silt loam soil was examined. When the herbicide was applied with surfactants (1:4, w/w, all HLB values), leaching of methazole was not affected. However, ratios of 1:1 and 4:1 (herbicide/surfactant) caused slight and significant retardation of movement, respectively. The influence of HLB of polysorbate surfactants was minimal. / Master of Science

Lime, chlorine, and potassium permanganate have long been important chemicals in the treatment of municipal and industrial wastewater. Their effectiveness in treating munitions manufacturing wastes was determined in a laboratory study using bench scale coagulation tests designed to simulate the facilities presently used to treat the wastewater. The wastewater from the new counter-current flow TNT manufacturing process at the Radford Army Arsenal Plant, Radford, Virginia, was found to be treatable by excess lime addition alone or in combination with the oxidants chlorine and potassium permanganate. The excess lime treatment removed 86 percent of the Silas-Mason reactable substances but created a color problem. The oxidants were employed to remove the color developed by the lime addition. Optimum color removal occurred if the chlorine was added to the waste at pH 6. The potassium permanganate treatment system was limited by the color imparted to the waste and by the slow reaction of the permanganate with the organic compounds in the presence of lime. Optimum color and TNT removal was obtained by adding the potassium permanganate at pH 2. A TNT removal of 81 percent was obtainable with a permanganate concentration of 50 mg./l. followed by excess lime treatment. Zinc sulfate addition marginally improved system performance. / Master of Science

With the advent of the "Space Shuttle" concept, it has become necessary to study the effects of heat transfer on the aerodynamic and boundary layer characteristics of a heated delta wing. Thus, a symmetrical 60° delta wing was tested up to twice freestream temperature in the Virginia Tech 6' x 6' stability wind tunnel. Summaries of the characteristics of the flow over the unheated wing and the theoretical effects of heat transfer are included. It has been found that heat transfer effects on the wing's aerodynamic characteristics are negligible at angles of attack up to one-third of the maximum lift angle. Beyond this, lift and pitching moment show a very small decrease and increase, respectively, up to maximum lift while drag increases 15 percent to 25 percent at maximum lift. Further increases in drag occur when the wing is yawed. No decrease in stalling angle of attack with heating is found for all yaw angles. / Master of Science