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The municipal solid waste collection routing is an important issue for waste management and the privatization policy that was recently initiated. Yet, the traditional experience-basedmethod is not capable of responding rapidly various demand and situation changes. An appropriated routing tool is trerefore explored. Furthermore, research in the routing field concentrated mostly on the reduction of cost, and the equity of workload among the collection crew and collection safety and convenience may be thus neglected. In this study, a mathematical model that can be resolved within reasonable computationsal time was proposed. The model considers, in addition to the cost, both the workload equity and vehicle turning efficiency. The complex structure of a real city street network makes it necessary to consider simultaneously directed, un-directed, and the not-served streets. Such a network is difficult to resolve by using a general routing model. For improving the model solvability, the original city street network is transformed to a totally dircted augmented network by a pre-treatment method developed based on the Minimum Cost flow. The augmented network is transformed again by the arc-to-node niethod into an equivalent node-based network. The finally transformed network is then possible to be resolved by using the proposed model within reasonable computational time. A case study in the east region of Hsinchu City was conducted. Total working time, total waste quantity, and the weighted sum of both previous measures are the three workload equity criteria studied. The result shows significant improvement in workload distribution, collection time, and vehicle turning efficiency, when compared with the current collection routing schedule.
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