OPTIMAL DISPATCHING OF AN INFINITE CAPACITY SHUTTLE: CONTROL AT A SINGLE TERMINAL

The optimal control of a shuttle system consisting of a single infinite capacity carrier transporting passengers between two terminals is studied. Passengers arrive according to independent Poisson processes, and dispatching decisions to hold the carrier for more passengers can be made at only one of the terminals. The objective is minimization of the long-run average of a linear passenger waiting cost and a fixed charge per trip made. When complete information about the system state is available, and travel times are deterministic, it is optimal to dispatch the carrier if, and only if, the total number of passengers waiting at both terminals is greater than a cutoff value. An iterative method for computation of the cutoff value is given and it is found that it can be well approximated by a function of system costs and parameters similar to the economic lot size formula. A (possibly non-optimal) dispatching rule is proposed for the case when only the number of passengers waiting at one terminal is known, and its efficiency is compared to that of the aforementioned optimal rule. Extensions to other optimality criteria and to the case of stochastic travel times are outlined.

• Supplemental Notes:
  • The Rand Institute ceased operations in 1977.
• Corporate Authors:

  New York City Rand Institute

  545 Madison Avenue
  New York, NY  United States  10022
• Authors:
  • Ignall, E
  • KOLESAR, P
• Publication Date: 1973-3

Media Info

• Pagination: 36 p.

Subject/Index Terms

• TRT Terms: Analysis; Control; Costs; Dispatching; Freight terminals; Information processing; Intermodal terminals; Iterative methods; Markov processes; Mathematical models; Mixing plants; Optimization; Passengers; Poisson distributions; Queuing theory; Random variables; Schedules; Scheduling; Traffic delays; Travel time; Waiting time
• Uncontrolled Terms: Batch processing; Cost analysis
• Old TRIS Terms: Aircraft capacity; Arrival; Arrivals; Queueing theory; Shuttles
• Subject Areas: Aviation; Finance; Freight Transportation; Passenger Transportation; Terminals and Facilities;

Filing Info

• Accession Number: 00168578
• Record Type: Publication
• Source Agency: National Technical Information Service
• Report/Paper Numbers: P-4979
• Files: TRIS
• Created Date: Dec 27 1978 12:00AM