Dantzig-Wolfe Decomposition of General Transportation Problems with Side-Constraints
DescriptionThis research is to develop a decomposition method for the side-constrained asymmetric traffic assignment problems (SCATAP) which is also called the side-constrained general transportation models. The proposed decomposition method applies the Dantzig-Wolfe decomposition method with truncated calculations to the SCATAP. The motivation of developing decomposition method is to provide ease model development and maintenance by the method that links separately developed submodels only when a global solution is desired. For example, a well-developed general transportation model can be further developed by adding some side-constraints through the decomposition method in order to carry out transportation policy analyses.By adding dummy variables for introducing the linking constraints to the SCATAP, the problem can be decomposed by the Dantzig-Wolfe decomposition into a master problem (an asymmetric TAP and a subproblem (a symmetric TAP with side constraints). The subproblem will be further decomposed with truncated calculation in order to speed up the computational rate although the major purpose of the research is not to develop faster solution method. The proposed method can be used as an environmental policy analysis tool for Hong Kong transportation system when the side constraints are emission control limits to ease Hong Kong's air pollution problems.
|Effective start/end date||1/01/09 → 16/02/12|