The basic framework of international time zones is that there is about one hour difference in solar time for every 15 degrees of longitude.

国际时区的基本框架是经度每隔15度，太阳时就相差一小时。

youdao

Basic scale topographic map is bases on one of million international map subdivision and divided by Longitude difference and Latitude difference.

我国基本比例尺地形图是以国际百万分之一地图分幅为基础，按一定的经差和纬差划分图幅。

youdao

The basic framework of international time zones is that there is about one hour difference in solar time for every 15 DE GREes of longitude.

国际时区的基本框架是经度每隔15度，太阳时就相差一小时。

youdao

So each hour's time difference between the ship and the starting point marks a ship's progress of fifteen degrees of longitude to the east or west.

VOA: special.2010.07.14