Figure A. 2 shows height contours for England and Wales, and demonstrates the size of the areas of concern.

图a . 2是英格兰和威尔士的海拔高度线，并标识出地区的危险等级。

youdao

Triangle network DTM building with concrete height points can be used for various aspects, e. g. generating contours, building surface model and calculating earthwork, etc.

由离散高程点建立的三角网d TM，能够在多方面应用。如生成等高线、建立地面模型、计算土方量等。

youdao

Its terrain-following radar can be linked to the aircraft's autopilot - so the plane itself can follow the contours of the landscape at a height of just 100 ft (30 m).

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