PERSONNEL TOUR SCHEDULING WHEN STARTING-TIME RESTRICTIONS ARE PRESENT

This payer presents an effective solution strategy for an important ca tegory of personnel scheduling problems. Specifically, we address the restricted starting-time tour-scheduling problem (RSTP), which involve s the determination of the hours of the day (shifts) and days of the w eek (days on) that employees are assigned to work. RSTP is characteriz ed by restrictions on the number of daily time periods in which employ ees may begin their shifts. Moreover, the RSTP we consider contains co nstraints that require separation of starting times. Such restrictions are widely encountered in practice and are based on a number of facto rs including managerial concerns for control of employee movements, un ion contractual obligations, and employee preferences for common shift starting times. A two-stage heuristic solution strategy is proposed f or RSTP. We developed eight heuristic procedures based on this strateg y and applied them to four sets of labor requirements, for each of 27 United Airlines (UA) airport ground stations. One of the best of these procedures yielded solution costs that averaged only 1.36 full-time-e quivalent employees above very conservative LP-based lower bounds. Mor eover, the solution costs obtained using this procedure were, on avera ge, 28 percent closer to the lower bounds than solution costs obtained using UA's current scheduling system. We conclude that the two-stage heuristic solution strategy is a valuable platform from which to devel op procedures for generating near-optimal solutions to this difficult class of personnel scheduling problems.