M.A. Dahleh. / Cover title. / Includes bibliographical references (leaf 8). / Research supported by the Center for Intelligent Control Systems under an Army Research Office grant. DAAL03-86-K-0171 Research supported by the NSF. 8810178-ECS

This report is a compilation and discussion of information on the implementation of and the measures of effectiveness of transportation demand management measures. The author addresses ten different strategies to reduce the demand on the transportation system. These strategies are: high occupancy vehicle lanes, ridesharing, vanpools, bicycle and pedestrian facilities, road pricing, transportation incentives and allowances, alternative work hours, parking management, telecommuting, and transit improvements. Each topic is briefly described and then followed by implementation issues, measures of effectiveness, and case studies. / Master of Science

Master of Science

The Fairfax County Water Authority (FCW A) is one of the largest water purveyors in Virginia, producing an average of 111 million gallons of water per day for approximately 960,000 people. Located in Northern Virginia, FCW A supplies drinking water to Fairfax, Prince William, and Loudoun Counties, the Town of Herndon, the City of Alexandria, and several federal institutions within the area. The Potomac River and the Occoquan Reservoir constitute the raw surface water supplies for the service area. On March 28, 1993, a 36-inch oil transportation line ruptured, spilling in excess of 400,000 gallons of No.2 fuel oil in the vicinity of Reston, Virginia. This massive spill severely contaminated the Potomac River and forced a complete shutdown of FCWA's Corbalis Water Treatment Plant (WTP) for 13 days. Since the Corbalis WTP normally meets 50 percent of the water demand, production from FCW A's other treatment facilities, drawing from the Occoquan Reservoir, had to be dramatically increased during a period of unusually harsh raw water conditions. / Master of Science

Master of Science

<p>Wetlands are complex ecosystems that have improved water quality by processes inherent to the system. There are varied criteria used to establish the existence of a wetland.</p> <p> During the last 20 years interest in the use of wetlands for wastewater treatment has increased. Natural and constructed wetlands were reviewed related to their ability to treat agricultural and domestic wastewaters, stormwater run-off, and acid mine drainage. Currently operating natural and constructed wetland treatment systems were reviewed using raw data and published articles. Treatment efficiencies related to nutrient and metals removal varied with the wetland configuration, climate, and types of wastewater treated.</p> / Master of Science

see document / Master of Science

Master of Science

<p>The risk of corn rootworm damage to continuously-grown corn was assessed in 32 fields from seven counties in Virginia in 1993 and 1994, Approximately 28% of the fields examined had economic root damage in corn left untreated with a soil insecticide. In addition, 19% of the fields overall had an economic loss in silage due to corn rootworm damage.</p> <p> A second study evaluated the effectiveness of using adult corn rootworm counts on commercial Olson yellow sticky traps and ear-zone regions of corn plants to predict subsequent damage to corn. Regression models for each sampling method were used to calculate economic thresholds of 20 adults per trap per wk for the Olson trap and 0.3 adults per stalk for the ear-zone visual count method. Adult counts on Olson traps obtained in mid-Aug correctly predicted economic damage to com 81% of the time; and resulted in only one serious error of failing to predict economic damage to corn. A sampling plan for the use of Olson traps is suggested.</p> <p>A third study investigated a possible sexual dimorphism in the elytra coloration pattern of western corn rootworm, and compared the sex ratio of adults captured yellow sticky traps with those obtained by aspiration. Striped and solid variations in elytra pattern were found in both sexes of western corn rootworm; however, 98% of the adults that exhibited the solid elytra pattern were male. The sex ratio of adults varied over time; however, in all cases, sticky traps captured a significantly greater proportion of males compared with aspiration.</p> / Master of Science

Master of Science