Chansung Kim

A comparative study on sampling strategies for truck destination choice model: case of Seoul Metropolitan Area

One of the major issues when applying truck destination choice models with a large number of alternatives is how to sample a set of non-chosen traffic analysis zones (TAZs) to construct a destinati...

Genetic Algorithm-Based Approach for Estimating Commodity OD Matrix

This paper proposes an estimation approach for a commodity origin-destination matrix by using a sample commodity origin-destination (OD) matrix from a Commodity Flow Survey and also mode-specific OD matrices obtained from a transportation record of freight carriers. The proposed approach is formulated as a multi-objective bi-level optimization problem in which the upper-level seeks to minimize the sum of square deviation from the target matrices, while in the lower-level, user-equilibrium assignments of commodity OD matrix from a CFS and mode-specific OD matrices are performed. The developed model and the Genetic Algorithms-based solution algorithm were validated and tested on an intermodal transportation network of Korea. The results show that the model is able to produce an acceptable commodity OD matrix, implying that the proposed approach is applicable for a real-world problem.

Modelling Truck's Destination Choice Model Behaviour: Case Study of Seoul Metropolitan Area

This study was to develop a disaggregate trucks destination choice model as a sub-model of a tour-based truck demand model. For this purpose, two distinct destination choice models for the first trip and post-first trips were developed. To determine if there is a competition or agglomeration effect in the choice of next stop location, the accessibility index was included as an explanatory variable in the logit-based choice model. The destination choice model, including accessibility as an explanatory variable, was found to be superior to that without the accessibility variable. More importantly, although there was a competition effect for the first trips destination choice, the agglomeration effect exists for the post-first trips destination choice, indicating that there is a competition effect in the destination choice of truck movements. The agglomeration effect for the post-first trips for a small-sized truck was found to be more significant than that for a medium-sized truck.