Answer / guezz who

is the change in frequency of a wave (or other periodic
event) for an observer moving relative to its source. It is
commonly heard when a vehicle sounding a siren or horn
approaches, passes, and recedes from an observer. The
received frequency is higher (compared to the emitted
frequency) during the approach, it is identical at the
instant of passing by, and it is lower during the recession.

We can applied this to Sirens, astronomy, temperature
measurement, flow measurement, vibration measurement,
radar, velocity measurement, audio, underwater acoustics,
and medical imaging.

difference between DCS @ SCADA system? and how can use in field

5 Answers   Marafiq,

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what are the possible reasons if a control valve fails to open/close?

1 Answers   DEWA,

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in yokogawa prosef rd safety PLC how to data send frome local SCS to other SCS and other FCS

2 Answers  

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what is meant by nuclear power plant?

1 Answers  

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selection of the zener barrier for the hazardeous area zone 0

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0 Answers  

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If a normal magnetic type flow transmitter that can measure flow, temperature and show this parameters on field, is it possible by any means to get this (flow and temperature) parameters info. On dcs? And if yes then with HART, FO communication or any other communication system?

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What is the use of control cable?

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1.can you use SCADA instead of DCS,DCS instead SCADA 2.Difference between DCS and PLC,can their role be reversed i.e. role interchange 3.Difference between RTU and PLC

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