一、引入竞争机制（一）重新认识垄断的传统领域本世纪７０年代以前，世界各国电力，铁路、邮电、煤气、公交产业均实行区域性独占的市场结构。主要原因是人们认为这些产业具有自然垄断性。所谓自然垄断，是指由于资源条件或规模经济的要求而无法竞争或不适宜竞争而形成的... I. Introduction of Competition Mechanism (I) Re-understanding of the Traditional Areas of Monopolization Before the 1970s, the power, railway, post and telecommunications, gas and bus industries all over the world applied a market structure that was monopolized by the region. The main reason is that people think that these industries have a natural monopoly. The so-called natural monopoly refers to the result of resource conditions or economies of scale that can not be competitive or unfit for competition.