SOLVING SINGULARLY CONSTRAINED TRANSSHIPMENT PROBLEMS

This paper develops a primal simplex procedure to solve transshipment problems with an arbitrary additional constraint. The procedure incorporates efficient methods for pricing-out the basis, determining representations, and implementing the change of basis. These methods exploit the near triangularity of the basis in order to take full advantage of the computational schemes and list structures used in solving the pure transshipment problem. Also reported is the development of a computer code, I/O PNETS-I for solving large scale singularly constrained transshipment problems. This code has demonstrated its efficiency over a wide range of problems and has succeeded in solving a singularly constrained transshipment problem with 3000 nodes and 12,000 variables in less than 5 minutes on a CDC 6600. Additionally, a fast method for determining near optimal integer solutions is also developed. Computational results show that the near optimum integer solution value is usually within a half of one percent of the value of the optimum continuous solution value.

• Corporate Authors:

  University of Texas, Austin

  Center for Cybernetic Studies
  Austin, TX  United States  78712

  Naval Personnel Research & Development Laboratory

  Washington, DC  United States 

  Office of Naval Research

  Department of the Navy, 800 North Quincy Street
  Arlington, VA  United States  22217

  University of Colorado, Boulder

  130 Academy Building, 970 Aurora Avenue
  Boulder, CO  United States  80309

  Tulsa University

  Tulsa, OK  United States 
• Authors:
  • Glover, F
  • Karney, D
  • Klingman, D
  • Russell, R
• Publication Date: 1974-12

Media Info

• Pagination: 32 p.

Subject/Index Terms

• TRT Terms: Calculation; Interchanges; Intermodal transportation; Linear programming; Mathematical models; Network analysis; Simplex method
• Uncontrolled Terms: Computation; Network flows
• Old TRIS Terms: Intermodal operations
• Subject Areas: Freight Transportation; Planning and Forecasting; Railroads;

Filing Info

• Accession Number: 00090894
• Record Type: Publication
• Source Agency: National Technical Information Service
• Report/Paper Numbers: CCS-212
• Contract Numbers: N00123-74-C-2275
• Files: TRIS
• Created Date: Jun 26 1975 12:00AM