These tiers could categorize methods of operation in conjunction with safety improvements such as separation of passenger and freight traffic and advanced train control systems.

这些安全措施包括将客运流量与货运流量隔离，升级列车控制系统等。

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With human supervisors in the passenger seat, seven test cars have driven 1, 000 miles without human intervention and more than 140, 000 miles with only occasional human control.

7辆测试车都有人坐在乘客座位上监视，在不需要人干预的情况下这些车已经开了1000英里。如果要开14万英里以上，人只需偶尔地控制一下车辆。

youdao

With human supervisors in the passenger seat, seven test cars have driven 1,000 miles without human intervention and more than 140,000 miles with only occasional human control.

7辆测试车都有人坐在乘客座位上监视，在不需要人干预的情况下这些车已经开了1000英里。 如果要开14万英里以上，人只需偶尔地控制一下车辆。

youdao

It will include dark tinted headlights, black grille, fog lamps, LED racetrack taillights, integrated dual exhaust, Bluetooth, cruise control and passenger in-seat storage.

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Most commercial aircraft in service recirculate 50 percent of the air delivered to the passenger cabin for improved control of cabin circulation, humidity and fuel efficiency.

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In a major development, Congress legislated control of the passenger railways and gave it to Amtrak.

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