There are unsatisfied circumstances of inadequate and excessive supplies of network information The reason is that some information providers haven′t acquired all the profits or undertaken all the costs of information providing,parts of profits or costs are owned by the exterior and not by themselves,so the externalities appear The paper points out that we can take economic measures to lighten the unfavorable effects brought by externalities,assisted by measures of law,technology and public opinion
以Web of science核心集数据库中收录的相关文献为研究对象,运用科学知识图谱和Citespace Ⅲ工具,着重从领域研究进展、统计分析、前沿热点与演变趋势多个角度进行深入探究。研究结果显示:新能源汽车是当前学术界的热点研究领域,但研究学者仅形成了几个小的研究群体;中国和美国的研究学者是该领域研究的中流砥柱,其学术成果占比超过50%,因此未来各个国家之间应进一步加强科研合作和联系;混合动力电动汽车将是新能源汽车领域未来研究的主攻方向;在未来,可再生能源、充电站和锂离子电池将会得到更多的研究和投入;国际研究经历了萌芽期、调整期和爆发式增长期3个演变阶段且每个阶段的研究重点各有不同。
