katabatic

Aclinic tone and assurgent tone take second place.Katabatic tone is always the shortest tone.

一个声调格局中一曲折调最长，平调和升调次之，降调最短。

For blower fan coil,adopting local drop ceiling when they are setting with new wind,but adopting a manner of katabatic wind when they arn’t setting with new wind.

对于管，加新部分采用局部吊顶，不加新部分采用下送方式。

Such results are gotten: (1) Due to the unique topography the wind of Beijing area during the day time is southern anabatic wind and in the night is northern katabatic wind in summer.

(1)北京区域夏季边界层场受西北特殊地形影响,夜间低层大气流场常表现为由北向南下坡,白天逐渐转为由南往北上坡。