layout method of highway route center stake based on measure traverse line 基于测量导线的公路中桩放样方法
oceans away : three air route centers ? in new york city, oakland, calif ., and anchorage, alaska ? monitor traffic over the atlantic and pacific oceans 隔海相望:美国共有三个航路中心(位于纽约市、加州奥克兰以及阿拉斯加的安克拉治)监控大西洋和太平洋上空的交通。