block signal

基本解释

He says, "It is easy for a patient's hair to get in the way and block the signal" with conventional fNIRS technology.
他说，"如果用传统的FNIRS技术，病人的头发很容易就挡住红外线，切断光谱信号。
A rail automatic block signal system based on the field bus technology is introduced, and its reliability design is explained specially.
介绍一种基于现场总线技术的铁路自动闭塞系统，并就其可靠性设计作了重点阐述。
The paper gives solutions to the problems with lighting circuit of permissive aspect of block signal of existing automatic block section according to relevant specifications.
通过对现有自动闭塞区间通过信号机容许信号点灯电路存在问题的分析，根据相关规范，提出解决办法。

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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Because tunnels block a radar signal, trains rely largely on hard-wired equipment like the box beside the track, which helps drivers and dispatchers talk to each other and controls a machinelike traffic signal, giving the drivers basic commands to stop and go.
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Speeds reached peaks of 16.7Mbps down and 9.4Mbps up with full signal but performance varied wildly, even block to block.
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