This paper introduces different signal block modes and the method which was used to calculate tracking intervals between trains, and establishes simulation system for multi-train tracking.

介绍了城市轨道交通不同信号闭塞方式及其追踪列车间隔时间的计算方法，建立了多列车追踪运行的仿真系统，并进行了算例的设计。

youdao

One space after a period is plenty to signal the end of a sentence. It also keeps the text block even.

一个空格足够区分二个句子，同时还能保证文本块的连续性。

youdao

A standard configuration is for a carrier is to use half of each block to send a signal, and half to receive (outbound and inbound traffic).

运营商的一种标准配置是使用一半的块来发送信号，另一半接收(即下行和上传通道)。

youdao

It works with wifi and bluetooth, sending a signal to a physical block attached to the Lockitron owner's door.

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No matter what part of the normal radio spectrum you pick, you will find some material that will reduce, deflect or block the signal entirely.

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Sometimes I had to walk around my house, waiting for a connection to reestablish itself. (Metal doors and thick walls can block a Bluetooth signal).

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