Chinese English

A line or surface showing the DEPTHS in OCEANS or LAKES at which points have the same tempera­ture. Isobathytherms are usually drawn to show cross sections of the water mass.

Line joining, on a CHART, places on the EARTH's surface where, on a given day, the first clap of THUNDER has been heard simultaneously. In CLIMATOLOGY, line drawn on a CHART through places which have the same average number of days on which THUNDER is heard in a given period.

在海图上，将地球表面在某一给定时期同时能听到第一声雷鸣的地点的连线。在气候学中，绘制在地图上的在给定期间内能听到雷声的平均天数同样多的地点的连线。

The unique point common to the plane of a PHOTOGRAPH, its PRINCIPAL PLANE, and the plane of an assumed truly VERTICAL PHOTOGRAPH taken from the same CAMERA STATION and having an equal PRINCIPAL DISTAN­CE. The point of intersection on a PHOTOGRAPH of the true PRINCIPAL LINE and the ISOMETRIC PARALLEL. The point on a PHOTOGRAPH intersected by the bisector of the angle between the PLUMB LINE and the photo­graph perpendicular. The isocentre is significant because it is the centre of radiation for DISPLACE­MENTS of IMAGES caused by TILT.

指像主距相同且来自于同一摄站的像平面、像主平面和假设的真垂直像片平面的唯一公共点。真正的主纵线和等比线的交叉点，像片上的这一点与铅垂线和照片垂线之间夹角的平分线相交。等角点是重要的，因为它是由于倾斜所引起的影像位移的辐射中心。

In the IALA Maritime Buoyage System a NAVIGATION MARK erected on, moored over, or placed immediately adjacent to an isolated danger of limited extent, which has NAVIGABLE WATER all around it.

在国际航标协会海上浮标系统中，竖立在或者系泊在或者即刻布置在紧邻孤立危险物的有限范围内（四周）的航行标志，其外围都是可航行水域。

A line representing the intersection of the plane of a VERTICAL PHOTOGRAPH with the plane of an overlapping OBLIQUE PHOTOGRAPH. If the VERTICAL PHOTO­GRAPH were tilt-free, the isoline would be the ISOME­TRIC PARALLEL of the OBLIQUE PHOTOGRAPH.

表示垂直摄影像片的平面与重叠的倾斜摄影像片的平面之间的交线。如果垂直摄影像片是无倾斜的，则等值线就是倾斜摄影像片的等比线。