absolute practical system of units
international practical system of units
practical system of units
2+1 talents cultivation system
1∶1 power assistant system
1+1 dimentional Boussinesq system
1 550nm transmission system
1 550 nm optical fiber transmission system
1 310 nm cable TV system
1310nm有线电视系统
磨粒喷射精密光整加工(AJF)
±800 kV DC transmission system
“single seat， single vote” system
“quasi-ministerial” system
“multi-seat， single-vote” system