Show simple item record

dc.contributor.advisorGarcia-Diaz, Alberto
dc.creatorChen, Ping-Shun
dc.date.accessioned2007-04-25T20:07:28Z
dc.date.available2007-04-25T20:07:28Z
dc.date.created2005-12
dc.date.issued2007-04-25
dc.identifier.urihttp://hdl.handle.net/1969.1/4779
dc.description.abstractThe purpose of this research is to develop a heuristic algorithm to minimize total costs in multi-commodity, multi-mode generalized networks with time windows problems. The proposed mathematical model incorporates features of the congestion of vehicle flows and time restriction of delivering commodities. The heuristic algorithm, HA, has two phases. Phase 1 provides lower and upper bounds based on Lagrangian relaxations with subgradient methods. Phase 2 applies two methods, early due date with overdue-date costs and total transportation costs, to search for an improved upper bound. Two application networks are used to test HA for small and medium-scale problems. A different number of commodities and various lengths of planning time periods are generated. Results show that HA can provide good feasible solutions within the reasonable range of optimal solutions. If optimal solutions are unknown, the average gap between lower and upper bounds is 0.0239. Minimal and maximal gaps are 0.0007 and 0.3330. If optimal solutions are known, the maximal gap between upper bounds and optimal solutions is less than 10% ranges of optimal solutions.en
dc.format.extent396955 bytesen
dc.format.mediumelectronicen
dc.format.mimetypeapplication/pdf
dc.language.isoen_US
dc.publisherTexas A&M University
dc.subjectLagrangian relaxationen
dc.subjectMulti-commodityen
dc.subjectMulti-modeen
dc.subjectGeneralized networken
dc.subjectTime windowsen
dc.titleCost minimization in multi−commodity multi−mode generalized networks with time windowsen
dc.typeBooken
dc.typeThesisen
thesis.degree.departmentIndustrial and Systems Engineeringen
thesis.degree.disciplineIndustrial Engineeringen
thesis.degree.grantorTexas A&M Universityen
thesis.degree.nameDoctor of Philosophyen
thesis.degree.levelDoctoralen
dc.contributor.committeeMemberAkleman, Derya
dc.contributor.committeeMemberBanerjee, Amarnath
dc.contributor.committeeMemberMalave, Cesar O.
dc.type.genreElectronic Dissertationen
dc.type.materialtexten
dc.format.digitalOriginborn digitalen


Files in this item

Thumbnail

This item appears in the following Collection(s)

Show simple item record