STOCHASTIC FREIGHT FLOW PATTERNS: IMPLICATIONS FOR FLEET OPTIMIZATION

Abstract Trucking, rail and other types of transportation networks share the common feature of moving equipment and crews between spatially separated terminals to accommodate the transportation of goods or people. This paper develops measures for temporal and spatial imbalances in freight flows, and applies these measures to a major trucking network. Fundamentally, the randomness inherent to a system of terminals is mitigated by pooling freight flows among terminal groups, and by pooling freight flows over many time periods. In the terminal network that we examined, long-run freight imbalances ensure that empty equipment movements must equal or exceed 13.3% of loaded movements at individual terminals and 8.2% of loaded movements at terminal groups. Due to short-run freight imbalances, the number of empty movements could increase by about 50% over the long-run average; greater increases would occur if equipment flows must be balanced on each travel lane. ©

[1]  Cynthia Barnhart,et al.  A Network-Based Primal-Dual Heuristic for the Solution of Multicommodity Network Flow Problems , 1993, Transp. Sci..

[2]  Warren B. Powell,et al.  THE DYNAMIC VEHICLE ALLOCATION PROBLEM WITH UNCERTAIN DEMANDS , 1987 .

[3]  Teodor Gabriel Crainic,et al.  Dual-Ascent Procedures for Multicommodity Location-Allocation Problems with Balancing Requirements , 1993, Transp. Sci..

[4]  Kenneth S. Nickerson,et al.  Maximizing Profits for North American Van Lines' Truckload Division: A New Framework for Pricing and Operations , 1988 .

[5]  S C Misra.  LINEAR PROGRAMMING OF EMPTY WAGON DISPOSITION , 1972 .

[6]  Teodor Gabriel Crainic,et al.  Survey Paper - A Review of Empty Flows and Fleet Management Models in Freight Transportation , 1987, Transp. Sci..

[7]  William C. Jordan,et al.  A STOCHASTIC, DYNAMIC NETWORK MODEL FOR RAILROAD CAR DISTRIBUTION , 1983 .

[8]  Michel Gendreau,et al.  Dynamic and Stochastic Models for the Allocation of Empty Containers , 1993, Oper. Res..

[9]  Warren B. Powell,et al.  A Stochastic Model of the Dynamic Vehicle Allocation Problem , 1986, Transp. Sci..

[10]  Mark A. Turnquist,et al.  A Model for Fleet Sizing and Vehicle Allocation , 1991, Transp. Sci..

[11]  William W. White,et al.  A Network Algorithm for Empty Freight Car Allocation , 1969, IBM Syst. J..

[12]  R. Hall,et al.  Fleet sizing and empty equipment redistribution for center-terminal transportation networks , 1997 .

[13]  H Herren.  THE DISTRIBUTION OF EMPTY WAGONS BY MEANS OF COMPUTER. AN ANALYTICAL MODEL OF THE SWISS FEDERAL RAILWAYS , 1974 .

[14]  Mark A. Turnquist,et al.  MODEL FOR MANAGEMENT OF EMPTY FREIGHT CARS , 1982 .

[15]  Joseph M. Sussman,et al.  INVENTORY MODEL OF THE RAILROAD EMPTY-CAR DISTRIBUTION PROCESS , 1977 .