A speed control system is also now in place for a northbound train in the crash zone.

调速系统已经安装在了事发地区向北始发的火车上。

In addition, they were built to help keep vehicles within a lane and to back up speed control systems.

另外，这些车型还搭载了车道保持辅助系统和倒车速度控制系统。

First, video is naturally adjustable, so make sure the pacing is right for you, by using the video speed controls.

首先，视频自然是可调的，因此请使用视频速度控件确保节奏适合您。