converter valve commutation failure
converter valve components
converter valve control system
transmitting noise of the HVDC converter valve
the ratio valve of air to fuel
digital-to-analog converter {= D-A converter}
wave converter waveform converter
axial compression ratio and slenderness ratio
B-C ratio (benefit-cost ratio)
benefit-cost ratio (B-C ratio)
focal ratio (=focal-length ratio)
grinding ratio(G-ratio)