Having multiple replicas also provides the project a failsafe mechanism to minimize project down-time and rework in the event of a server outage.

拥有多个副本也为项目提供了一个安全机制，可以在服务器运行中断过程中减少停机时间及返工。

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Part of the advantage of 3D printing is the ability to make a variety of individually customised parts at a similar cost to making multiple, identical replicas.

BBC: How 3D printing will change travel