Total mainframe power switch could not be activated: check whether the Master relay is damaged, whether the flow relay tripped.

主机总电源开关不能启动：检查主令继电器是否损坏，过流继电器是否跳闸。

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And then the software system which includes master, relay unit and module unit was designed on the basis of hardware.

在硬件的基础上设计了包括上位机、中继单元和模块单元在内的软件系统。

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The master communicates with the relay unit by serial communication interface and the relay unit communicates with module unit by wireless communication network.

上位机和中继单元之间采用串行口通信，中继单元和模块单元之间采用无线网路进行通信。

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They take aim at one or more of three emerging targets: These are peroxisome proliferator-activated receptors (PPARs), which are akin to master relay switches that control how the body uses sugar and fat.

FORBES: Silencing "Syndrome X"