protection reference model
Institute for Reference Materials of Environmental Protection Ministry
inertial [reference] frame, inertial [reference] system
optical reference filter wavelength standard reference material
Bureau of Environmental Protection Inspection of State Environmental Protection Administration
DISTANCE PROTECTION AND IMPEDANCE PROTECTION
Environmental Protection Industry Management Center of Shanxi Bureau of Environmental Protection
main protection Principle and setting of out-of-step protection for high-rating generator
Path protection and multiplex section protection
relay protection redundant sets of protection
(thermo) reference material
137Cs reference inventory
3D forward looking reference map
absolute cell reference