首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献,搜索用时 531 毫秒
1.
2.
3.
4.
5.
6.
7.
8.
9.
10.
It is the thesis of this paper that there are many technical opportunities for significant improvement of transportation productivity and quality. The paper describes specific examples of possible enhancements of existing systems as well as new system candidates. Generic properties of transport systems are discussed, and the probable directions of continuing system evolution identified. The process of innovation is analyzed, and some implications of its properties for the roles played by the private and public sector are characterized.  相似文献   

11.
12.
13.
14.
15.
16.
17.
18.
19.
20.
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号