Capacitated arc routing problem in uncertain environments

In this paper, the Uncertain CARP (UCARP) is investigated. In UCARP, the demands of tasks and the deadheading costs of edges are stochastic and one has to design a robust solution for all possible environments. A problem model and a robustness measure for solutions are defined according to the requirements in reality. Three benchmark sets with uncertain parameters are generated by extending existing benchmark sets for static cases. In order to explore the solution space of UCARP, the most competitive algorithms for static CARP are tested on one of the generated uncertain benchmark sets. The experimental results showed that the optimal solution in terms of robustness in uncertain environment may be far away from the optimal one in terms of quality in a static environment and thus, utilizing only the expected value of the random variables can hardly lead to robust solutions.