The method of multiple scales is used to analyze the nonlinear effects of the gas motion as well as the acoustic lining material on the propagation and attenuation of sound in two-dimensional and circular ducts of uniform cross sections in the absence of mean flow. The ducts are lined with a point-reacting acoustic material consisting of a porous sheet or of a perforated plate followed by honey-comb cavities and backed by the impervious walls of the ducts. The effect of the acoustic material is included either by characterizing the material by a semi-empirical nonlinear impedance or by coupling the waves in the duct with those in the liner. Analytical expressions are obtained for the absorption coefficient in terms of the sound frequency, the physical properties of the porous sheet or the perforated plate, and the geometrical parameters of the flow configuration. The results show that the nonlinearity flattens and broadens the absorption vs. sound frequency curve, irrespective of the geometrical dimensions or the porous material acoustic properties, in agreement with the experimental observations. The effect of the gas nonlinearity increases with increasing sound frequency, whereas the effect of the material non- linearity decreases with increasing sound frequency. Moreover, the sharper the resonant tuning is the narrower the adverse frequency bandwidth is. / Ph. D.

This dissertation examines three aspects of banking behavior: (a) involvement of banks in inflationary processes, (b) the effects of inflation on bank earnings and (c) the portfolio behavior of banks in an inflationary period. The study first traces the evolution of the"credit theory of inflation" from the eighteenth century to the early twentieth, and finds that under certain conditions banks may ignite an inflationary process by failing to adjust their loan rates to the real rate of interest. The analysis of the second aspect of banking behavior is carried out at the micro-economic level. After a critical appraisal of Martin Bailey's macro model of banking behavior under conditions of fully anticipated inflation and a competitive market structure, the study finds that Bailey's conclusion as to the favorable effects of inflation on bank profit is inconsistent with his model. The study revises Bailey's model and develops two models of banking behavior along the lines of the neoclassical approach of manufacturing firms. The first model examines banking performance under conditions of a competitive market structure and fully anticipated inflation. The model predicts that under these circumstances the banking system is more likely to lose than gain from inflation. The second model analyzes banking behavior when the banking market is characterized as monopolistic. It is inferred that no definite conclusions may be drawn with regard to the effects of inflation on bank earnings without an empirical knowledge of the parameters of the demand for loans and the supply of funds to the banking system. The study also analyzes banking behavior under conditions of unanticipated inflation. It is found that if savers respond to changes in the rates of interest only after a time lag, or if their subjective probability distribution of expected returns on income earning assets is biased downward, banks are in a position to earn some windfall gains from inflation. The third section of the dissertation analyzes bank portfolio behavior under both anticipated and unanticipated inflation. It is shown that unanticipated inflation forces the banks to alter their portfolio of income earning assets, and it is argued that such activities by banks may nullify the restrictive monetary policies that the monetary authority may impose upon the money market to slow down the rate of inflation. The study also presents evidence on the profitability of Chilean commercial banks during 1937 to 1950, and finds that due to the special rediscounting provisions of the Chilean Central Bank these banks earned more than average rates of return on their capital outlay, The study also suggests that the Chilean commercial banks were instrumental in perpetuating the inflation. Evidence is also presented on the portfolio behavior of U.S. commercial banks for the period 1950 to 1970. It is shown that the U.S. commercial banks moved from long-term assets to short-term assets during all the expansion periods observed between 1950 to 1970. This behavior by U.S. commercial banks is explained by the differential impact of the unanticipated inflation on short-term and long-term rates of interest for the period under review. / Doctor of Philosophy

The effects of contaminated supply air on the performance of a laminar proportional amplifier were experimentally investigated. The air supply was contaminated with oil vapor and particulate matter. Characteristic gain curves were obtained after each stage of contamination for various loading conditions. Photographs showing the location of contaminant deposits were taken. Two inlet geometries were studied: right-angle and straightthrough. The effects of maintaining a constant pressure and constant flow rate at the inlet throughout the duration of the tests were studied. Also, aspect ratio effects. were studied. Rapid deterioration of performance was evident with the right-angle entry due to inlet blockage. By milling a cavity in the bottom cover plate, the detrimental effects of inlet blockage were delayed. With constant pressure inlet conditions and straight-through geometry, significant buildup occurred in the nozzle region and downstream. Decrease in pressure recovery was linear with time. It was determined that null shift was caused by asymmetric buildup in either the nozzle region or splitter region. With constant flow inlet conditions, the damaging effects on performance were delayed for both inlet geometries. Also, for the straight-through inlet, the nozzle region was relatively clean when compared with the constant pressure inlet case. Null shift was found to be the result of asymmetric buildup in the downstream region. At lower aspect ratios, the damaging effects of contamination were more severe and occurred in less time. / Master of Science

The objectives of this research were to present an original formulation of a significant facilities location problem, the traveling salesman location problem, and to develop several heuristic solution procedures for determining minimum distance locations. Despite the wide applicability of the traveling salesman location problem, a survey of the facilities location literature revealed that this research effort apparently was the first to address the problem. After mathematically formulating the problem, several rather simple example problems were investigated in order to gain some insight regarding the behavior of the function under a variety of different conditions. Many of the results stemming from the study of the simple examples were counter-intuitive. Additionally, it was demonstrated that even for problems involving only a few existing facilities the resulting objective function is non-convex. Due to the non-convexity of the objective function and the overwhelming combinatorics involved with just one functional evaluation, it was desired that the solution procedures developed be capable of obtaining near optimal solutions in the shortest time possible. One of the solution techniques proposed, Procedure 2, was based on the Successive Quadratic Approximation Procedure. This procedure was selected for two reasons: 1) It was expected that the procedure would yield minimum solutions to large problems rather quickly, and 2) It was hoped that by approximating the function over the entire solution space, the procedure would tend to overlook local minimum points, and instead, find a global minimum point. It was demonstrated that while Procedure 2 is capable of obtaining optimal solutions, it does not immediately recognize a particular solution as being optimal. The other procedure proposed, Procedure 1, based on a relationship between the Steiner-Weber problem and the traveling salesman location problem, was selected because of its ability to immediately recognize a particular solution as being a local minimum point. At each iteration Procedure 1 required the solution of a Steiner-Weber problem as well as solutions to the "string" of traveling salesman problems. The Steiner-Weber problems were solved through the use of the Hyperbolic Approximation Procedure. It was verified that both procedures are capable of obtaining optimal solutions by applying each procedure to several of the example problems. The effectiveness of each procedure in finding minimum distance solutions was determined by applying each procedure to a number of randomly generated problems, and then comparing the resulting execution times and minimum distance solutions. A difference of two percent or more between the minimum distance solutions obtained for a given problem was considered to be significant. Problems involving 4, 6, 8, 10, and 11 existing facilities were solved. No attempts were made to solve larger problems due to the excessively long execution times required. On the basis of the computational results obtained, it was concluded that 1) There is no significant difference between Procedures 1 and 2 for problems involving four existing facilities. 2) For about 15 to 20 percent of the problems involving 6, 8, 10, or 11 existing facilities, Procedure 1 performs better than Procedure 2. By examining the mean execution times for each procedure, it was found that there was little significant difference between the two procedures until rather large problems were solved. Procedure 2 required relatively shorter execution times than Procedure 1 for problems involving 10 or 11 existing facilities. However, the reduction in execution time for Procedure 2 occurred at a point where it was considered economically infeasible to continue to examine larger problems. The length of execution times for larger problems can probably be reduced by: 1) Eliminating the need to evaluate all traveling salesman problems by setting many of the PhiS, the subset probabilities, equal to zero, and 2) Replacing the branch and bound algorithm for solving traveling salesman problems with one of the more effective heuristic procedures that have been developed. / Master of Science

A case study of innovation in local government within the context of planning and land use control was performed. Political and administrative aspects of the management of growth in Fairfax County, Virginia, were analyzed. Recent trends that influence local leadership in development regulation were explored. A survey of suburbanization in Fairfax County, governmental measures in planning and land use control, and the county's legacy of legislation, administration, and development regulation was conducted. The record of the present Board of Supervisors and county government in general administration and growth management was reviewed. Board interaction with administrative staff, advisory bodies, and citizens was assessed. An appraisal of the Board's initial steps to regulate development was made. / Master of Arts

Although strategies to meet most management objectives are relatively clearcut in single-species catchable trout programs, strategies become much more complex when two or more species are involved. A difficult problem that must be faced in evaluating catchable trout fisheries management strategies is defining management objectives. One approach to testing alternative management strategies in complex resource systems, such as catchable trout fisheries, is systems simulation. A computer-implemented catchable trout fishery simulator (CATS) was developed to evaluate fishery response under various management strategies in a multi-species stocking program. The user of CATS can select alternative management strategies and functions which generate predictions of fishing pressure on a particular fishery. To evaluate the effect of each system component, CATS was exercised over a wide range of potential system component alterations. Predominant stocking of brook trout appreciably increased average catch per angler hour and percentage return to creel. Altering the stocking ratio to favor brown trout substantially increased the number of angler hours. Stocking predominantly rainbow trout reduced the effects caused by stocking predominantly brook or brown trout. Estimates of expected angling pressure ru1d catchability coefficients of each species stocked are of primary importance because of their considerable effect on other system components. A user must have a sound objective before deciding where, when, which species, and how many fish to plant. The primary utility of CATS is to enable the user to evaluate management strategies prior to implementation. / Master of Science

A self-instructiona1 kit identifying seventy-three indoor plants, their cultural requirements, and uses was prepared. The kit consisted of seventy-eight slides of the plant material and a forty-fife minute taped narration. The botanical and common names of each plant along with its moisture, temperature, and light requirements were superimposed on each slide. Each plant's unique characteristics and uses were described by the script of the tape which averaged approximately thirty seconds per plant. / Master of Science

Many lipophilic pesticides are known to be transferred to offspring via the mother's milk. The present study was conducted to determine how much endrin was transferred from endrin resistant and susceptible dams to their suckling pups and to further characterize the effects that endrin may have on the hepatic mixed function oxidase (MFO) system in the pups. Dosing of the dams with endrin began one day after birth with either (l) oral doses of endrin in corn oil or (2) a mixture of endrin in ground feed. The total amount of endrin in the pup was determined by gas chromatography. MFO activity was determined in 2-1/2 week old pups and for adult animals using maximal activities for the demethylation of ethylmorphine and hydroxylation of aniline. No difference in the amount of endrin present in the pups was observed between strains provided both received equal amounts of endrin. MFO activity for endrin dosed mature animals and for 2-1/2 week old pups from endrin dosed dams exhibited a significant decrease from control activities. There was no difference in MFO activities between age groups. A significantly higher ethylmorphine demethylase activity was observed in comparing the resistant to the susceptible strain but there was no significant difference in aniline hydroxylase activity. / Master of Science

A method using gas chromatography for the analysis of carbon dioxide, carbon monoxide, and nitric oxide in diesel exhaust was developed. A gas chromatograph containing a liquid phase column in series with a molecular sieve column, each of which eluted into thermal conductivity detectors, was utilized. Activation of the molecular sieve column was achieved by heat-treating and purging with nitric oxide. The chromatograph was calibrated by introducing sample mixtures of known concentration and measuring the responses. The exhaust gases of a diesel engine were analyzed while the engine operated at constant speed and load. Engine speed was kept at 1400 rpm while several different loads were applied. The results of these tests indicated that carbon dioxide, carbon monoxide, and nitric oxide concentrations all increased with load in the load range studied. Carbon monoxide exhibited a greater dependence on load than did the other compounds. Additionally, water was injected into the intake air stream to study its effect on nitric oxide concentration. Nitric oxide levels were reduced by 15% when a water/fuel mass ratio of 0.75 lb/lb was used. / Master of Science

An artificial larval medium for colonized Culicoides guttipennis was developed. Microorganisms in decaying leaf matter were present in the original laboratory diet. These were believed to be the main food of C. guttipennis larvae. This was verified by sterilizing the leaf matter to kill the organisms present. Larvae did not develop beyond the first instar in this medium, but adults were produced from non-sterilized leaf matter. The objective was to develop cultures of various microorganisms and find one that would be best for rearing C. guttipennis larvae in producing more adults. A simple hay-infusion medium inoculated with stump-hole microorganisms was found more effective than all other cultures screened in rearing the larvae. This culture consisted of stump-hole microorganisms inoculated fresh each week from stored stumphole contents. It was compared with the same culture containing stumphole microorganisms completely adapted to a laboratory environment. The former was better in rearing C. guttipennis larvae. A final experiment evaluated the incorporation of vermiculite as an artificial substrate. This proved successful in rearing larvae and producing large numbers of adults. This culture was superior over the larval rearing medium of decaying leaf matter. Development of a successful artificial larval medium for colonized C. guttipennis will aid in establishing other laboratory colonies of related Culicoides species. / Master of Science