This service usually forwards the messages on to other SIP services, or translates the messages and invokes other types of equipment (like the call control elements in the control plane).

该服务通常将消息传递给其他 SIP 服务，或者解释消息，并调用其他类型的装置（像控制面板中的调用控制元素）。

youdao

We looked up, and the plane came straight over us, and it was turning, "the caller told emergency services."

看，那飞机直朝我们飞过来了！它在转，它在转！

youdao

Parker Hannifin Corp., which makes fuel, hydraulics and flight control systems for the plane, expects 500 ARJ21s could earn it $275 million in revenue and at least that much in after-sales services.

为该机生产燃料、液压系统和飞行控制系统的派克汉尼汾公司(Parker Hannifin Corp.)预计，500架ARJ21能使其获得2.75亿美元的收入，而售后服务的收入至少也有这个数。

youdao

The Emergency Services Ministry said the plane, which it said was flying in from the northern city of Kokshetau, disappeared from radar around 13:13 p.m. local time (0713 GMT).

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