RRC lies in the 3 rd sublayer of air interface protocol stack, the main function of which is the control and management of radio resource.

无线资源控制子层位于空中接口协议栈的第3层，它主要完成无线资源的控制和管理功能。

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Staged combustion engines in service include the Russian RD-180, used on the Atlas v, and the Space Shuttle Main engine.

在服务分级燃烧发动机包括俄罗斯的RD - 180，阿特拉斯v上使用，航天飞机主发动机。

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The Atlas 5 rocket that launched today stands 191.2 feet (58.3 meters) tall and includes one main booster powered by the RD AMROSS RD-180 engine.

MSN: Shhh �� Air Forces launches secret US spy satellite