Optimizing the Door Assignment in LTL-Terminals

Inbound doors and suitable time slots need to be assigned to arriving trucks for unloading in less-than-truckload (LTL) terminals. There needs to be simultaneous allocation to outbound doors for waiting trucks. All incoming truck shipments are, within a couple of hours, unloaded, sorted by relations, transported to the right outbound door, and loaded onto the outgoing truck. ("Destination" is an equivalent term to "relation," which originates from a German logistics vocabulary in which the term is used to specify a certain transport connecting a source and a sink.) Minimization of total distance when transshipping units is the first and most important optimization aim, since this leads to reduction in usually very high operational costs. Waiting time minimization for each truck is the second, and minor, aim. When collecting and delivering goods, usually subcontractors work with the LTL transshipment building operator. In case waiting times are too long, therefore, operators do not have to pay any penalties. Modeling of the logistical optimization tasks is performed as a time-discrete, multicommodity flow problem with side constraints. There is development of a modified column-generation approach and a decomposition approach based on the applicable model. In order to tackle the parallel problem at hand, an evolutionary algorithm is implemented. There is application of both algorithms to ten test scenarios - from both the field of computational intelligence and the field of discrete mathematics. The work is concluded by comparing both the solution process and solution quality.

• Availability:
  • Find a library where document is available. Order URL: http://worldcat.org/oclc/1767714
• Authors:
  • Chmielewski, Annette
  • Naujoks, Boris
  • Janas, Michael
  • Clausen, Uwe
• Publication Date: 2009-5

Language

• English

Media Info

• Media Type: Print
• Features: Figures; References; Tables;
• Pagination: pp 198-210
• Serial:
  • Transportation Science
  • Volume: 43
  • Issue Number: 2
  • Publisher: Institute for Operations Research and the Management Sciences (INFORMS)
  • ISSN: 0041-1655
  • Serial URL: http://transci.journal.informs.org/

Subject/Index Terms

• TRT Terms: Algorithms; Costs; Doors; Less than truckload traffic; Mathematical models; Operations; Optimization; Truck terminals; Waiting time
• Uncontrolled Terms: Assignment problems; Time factors; Transshipments
• Subject Areas: Freight Transportation; Highways; Motor Carriers; Planning and Forecasting; I21: Planning of Transport Infrastructure;

Filing Info

• Accession Number: 01131430
• Record Type: Publication
• Files: TRIS
• Created Date: Jun 30 2009 8:32AM