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This study evaluates the economic feasibility and profi tability of producing industrial sugar juice and ethanol using energy beets in the Northern Plains of the United States. An enterprise budget is constructed to estimate the breakeven price of energy beets that triggers farmers to produce the crop. This breakeven price is used to estimate the long-run breakeven prices for industrial sugar juice and ethanol. Stochastic models are developed to account for price and parameter variability in the estimation of enterprise budgets and breakeven prices. Results show that the simulated breakeven price of producing ethanol is 518 $m -3 and that of industrial sugar juice is 351 $t -1 , using a 36 $t -1 breakeven delivered cost of energy beets. Energy beet ethanol investment could be profi table at the breakeven prices of energy beets and ethanol computed, and could attract new capital investment into the ethanol industry.

The school bus routing problem traditionally has been defined in an urban context. However, because of the unique attributes of the problem in rural areas, traditional heuristic methods for solving the problem may produce impractical results. In many cases, these characteristics also provide the opportunity to investigate what size and mix of vehicles, whether large or small buses, conforming vans, or other modes, are most efficient. In addition, these vehicles may be further differentiated by the presence of equipment for transporting students with special needs. To address this situation, a mathematical model of the problem was constructed and a new heuristic was developed. This heuristic consists of two parts: constructing the initial route and then improving it by using a fixed tenure tabu search algorithm. This rural routing heuristic, in addition to several existing ones, is then applied to a randomly generated school district with rural characteristics. For the relevant measure, a function of student ride time, the new heuristic provides a set of routes superior to those produced by existing methods. Because ride times produced by the new heuristic are lower than those for routes generated by existing methods, the likelihood of injury to students may decrease. Also, with the cost of operation for each route calculated in dollars, a comparison of solutions in financial, as well as temporal, terms is possible.

With higher fuel costs and changing economic conditions, travel behavior and the level and allocation of resources in highways, rail, air, and transit service in rural areas may be changing. The objective of this study is to determine the attitude of would-be passengers in their choice of mode and the factors determining their choice in rural and small urban areas. A stated preference survey was developed and administered to residents of North Dakota and northwest and west central Minnesota. The survey asked respondents to identify their mode of choice in different hypothetical situations in which five modes were available—automobile, air, bus, train, and van—under differing mode and trip characteristics. A multinomial logit model was used to estimate the likelihood that an individual would choose a given mode on the basis of the characteristics of the mode, the characteristics of the individual, and the characteristics of the trip. Results show that travelers, especially those of lower income, respond to higher gasoline prices by choosing alternative modes in greater numbers, suggesting rural intercity bus, van, and rail ridership would increase if gasoline prices rose.