Railroad signal power system is a special supply power source for train running. The high reliability is required. Thus, its supervisor and control become very important.

铁路信号电源系统是专门给列车运营信号供电的，其可靠性要求非常高，因此，对铁路信号电源的监视和控制十分重要。

youdao

One Source for Power Supply - Charges virtually any technology that charges via a USB cable, including smartphones and phones, iPads and Kindles, iPods and other MP3 players, GPS units, tablet computers, etc.

ENGADGET: Timbuk2 Power Commute carries your gadgets, keeps 'em charged for $199 (hands-on)

Autonomous control over supply, via aggregation in unions, became their only source of power.

FORBES: Entrepreneurs are the New Labor: Part I

Each unit can also serve as a source of electrical power for the military, or emergency response, something always in short supply in forward operating positions.

CENTERFORSECURITYPOLICY: Value of Jake as a ready innovation base