## Data Source
This is a random data set generated by the author of this paper using the method reported in [Zarandi et al. 2011](https://www.sciencedirect.com/science/article/pii/S1026309811002100).
For each node, the two-dimensional Cartesian coordinate is randomly generated by unifrom distribution $U (0, 30)$ and the demand is generated by $U (0, 100)$ at random.
