According to action principle, extinguishing process and efficiency of the sprinkler systems, it is put forward that the ringed arrangements replace the ramiform arrangements.
The results showed: inncrease application of Ca, balance application of N and K and sprinkler irrigation could increase Ca content of lettuce leaves, reduce occurring of tipburn.
This article makes comparative analysis of the sectorization for the sprinkler system used in high-rise building and approaches to the details for pressure reduction and choice of fire-fighting pumps.