coupling mechanism between upper level and low level jet

fiscal system at county level and township level

interaction between upper level and lower level

municipal level and county level

a point of safe return

agro-machinery safe village

always safe geometry

automatic safe controller

available safe egress time

available safe evacuation time

benifit from safe operation

beyond safe limit

buckling safe factor

canal safe transit system

capital safe

cave roof safe thickness

check safe coefficient

China Alliance for Safe Injection

clean and safe water