Assertion: engine's intake | /r/HasProperty | open
Facets:
value: simultaneously
type: MANNER
Source sentences:
text: The closing of the exhaust valve on occurred more than 30 degrees later than on earlier engines, giving a long 'overlap' period (when both the intake and exhaust valves are open).
text: The momentum of the gases assists in scavenging during the 'overlap' phase (when the intake and exhaust valves are simultaneously open).