In a virtual storage system, a fixed-length block of contiguous virtual addresses copied as a unit from memory to disk and back during paging operations.

在虚拟存储系统中，一个固定长度的连续虚拟地址块，在分页操作过程中它作为一个单位在内存和磁盘之间来回复制。

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If the car is stolen, a coded cellphone signal will tell the unit to block the vehicle's engine management system and prevent the engine being restarted.

如果汽车被盗，一个被编码的无绳电话信号就会告诉这个装置停止车辆引擎控制系统来阻止引擎再次被启动。

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But when loops, several spread-spectrum radios and centre control unit (moving block system with 'centralized' structure) fail, the system can not be running in the ATC mode.

但是当环线、多个扩频电台、中央控制单元(“集中式”移动闭塞系统)等设备出现故障时，系统将无法工作在ATC模式下。

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