Centralization and diffusion are the two basic characteristics of central cities. The characteristics will be strengthened with city quality enhancement and transportation network development. 中心城市具有集聚和扩散这两种基本运动形式,其集聚力和扩散力随着其城市质量的提高而增大,随着交通网络的发达而提高。
The reliability and power quality of the power network have been improved with continuous expansion of the power network and enhancement of the network connection. However, the potential risk of power system malfunction is also increased. 电网规模的不断扩大,联网程度的增强可以提高电网的可靠性与供电质量,但同时也带来了潜在的危险。