1 Introduction
A city has diverse aspects to model and simulate; and these aspects have interwined effects among themselves. For instance, the traffic infrastructure of a city can be simply modeled from either traffic flow or the traffic entity perspectives, but this sinlge dimensional approach becomes a hurdle in the holistic comprehension of the city population, infrastructure, and their interwined lifestyles; while such a single aspect model becomes a very specific model to calibrate and validate at the engineering or the operational resolutions.