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

Entocytherid ostracods were collected on crayfishes inhabiting the James and York River basins of Virginia. Of the seventeen species encountered, only one (Donnaldsoncythere ardis) seems to be endemic. Ankylocythere ancyla, Dactylocythere banana, Dt. falcata, Dt. suteri, Donnaldsoncythere ardis, Dn. hiwasseensis, Dn. truncata, Entocythere sp. A, E. internotalus and Phymocythere phyma occur on the crayfishes Cambarus acuminatus, C. b. bartonii, C. longulus and Orconectes juvenilis in the streams of the Valley and Ridge Province. In the Coastal Plain where sluggish streams are encountered, Ankylocythere telmoecea and Ank. tiphophila are associated with Procambarus a. acutus. Cambarus acuminatus is also found in the Coastal Plain in moderately flowing streams and it is infested with Dactylocythere suteri and Donnaldsoncythere hiwasseensis. The primary burrowing crayfish of the Alleghany Mountains (Cambarus dubius) is host to Ascetocythere asceta and Dactylocythere chalaza whereas its ecological similar Cambarus d. diogenes of the Piedmont and Coastal Plain is the only host known with certainty for Dactylocythere jeanae, Okriocythere cheia and Ornithocythere waltonae. Ankylocythere tiphophila is associated with Fallicambarus uhleri, an inhabitant of swampy areas and marshes and may ocassionally construct simple burrows in the Coastal Plain. / Master of Science

The 1972 amendments to the Federal Water Pollution Control Act provide for major changes to reduce and eventually eliminate water pollution by 1985. In contrast, projections indicate that the volume of wastes generated by population and economic growth in the near future will be very large and the cost of treating it by standard methods will be extremely high. Hence, all possible systems and methods of waste disposal must be considered and ways of reducing the amount of waste discharges sought. In attempting to reach the goal of zero waste discharges, one alternative which must be considered in certain situations is the employment of deep well waste disposal (DWWD). This method accomplishes long term isolation of highly toxic liquid industrial wastes in confined subsurface geologic strata. This study undertakes a preliminary investigation of the potential of DWWD as a waste management tool. The analysis is conducted from an economic standpoint with the relevant economic concepts and issues being identified and examined as they apply to both users and regulators of the method as well as the general public. The direct cost for the system and its operation was discussed with particular attention paid to its derivation. Numerous site specific variables prevent generalizations concerning the cost of DWWD relative to surface treatment methods. On occasions, however, the method appears to have a greater initial capital outlay requirement but a much less operating and maintenance cost than alternative forms of wastewater management achieving the same effect. The social costs and benefits of deep well waste disposal were viewed in detail. Suggestions were made as how society might compensate the firm for the creation of social benefits in excess of social costs, and how they may be internalized into the firm's decision making process. Finally, the industrial potential for employing DWWD in the study area, designated as the Mid and South Atlantic states, is derived and discussed. / Master of Science

In this thesis the applicability of a hospital patient flow model is used in addressing hospital resource allocation problems. Three separate but interrelated models are presented. First, the hospital patient flow model is discussed. The main feature of the hospital patient flow model is the matrix of technical coefficients, which gives the probability of patient transfers throughout the hospital. Given the hospital system's daily patient input, the model provides the patient demands upon the different hospital services. Results from the patient flow model are used in the development of a staff allocation model. The staffing model involves the minimization of a weighted quadratic penalty function. The weighting factors are based on the proportion of patients in each of three carelevels in the wards. The weights are also dependent upon whether overstaffing or understaffing is the situation. Constraints to the model include a desirable mix and number of the available nursing staff. Solution of the allocation model is obtained by using SUMT with a pattern search. A third model concerned with predicting hospital revenues is presented. Again, results from the hospital patient flow model are used to present estimates of the expected values and variance of a hospital's revenue. To illustrate the use of the models, results from a two-week study period of the Montgomery County Hospital are presented and discussed. / Master of Science