The semantic diagram can only show a small percentage of these connections before it begins to look extremely disorganized and confusing. A city also has buildings, which contain offices, businesses, jails, apartments and garages. Most of the nodes in the network will have characteristics such as size, shape and color. We often take some of the nodes for granted. That is until Mother Nature comes along and takes them away.
Electricity allows many other nodes to exist.
Some such systems are the HVAC system in the substructure of the buildings, the lighting systems and even the appliances that we use everyday. As you can see, designing a city is a very complex and intricate process that takes a lot of thought and planning. One must consider all the relationships involved to get so many nodes working together smoothly.