GLOSSARY ENTRY (DERIVED FROM QUESTION BELOW) | ||||||
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00:39 Mar 11, 2016 |
English language (monolingual) [Non-PRO] Engineering (general) | |||||||
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| Selected response from: Charles Davis Spain Local time: 22:01 | ||||||
Grading comment
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SUMMARY OF ALL EXPLANATIONS PROVIDED | ||||
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4 +5 | these detectors can be programmed to ignore harmless disturbances |
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these detectors can be programmed to ignore harmless disturbances Explanation: I have looked up the study from which this comes. It refers to a type of detector known as an "electronic nose", with sensors that can detect the chemical composition of the surrounding air and respond by giving the alarm when that composition suddenly changes, as it does in the early stages of a fire. However, it would be a nuisance if the detectors gave a lot of "false positives"; that is, if they sounded the alarm when there is no fire. Therefore they are programmed to recognise composition patterns associated with known harmless changes that can occur and that do not indicate a fire. These are the "harmless disturbances"; "harmless" means what it says (they will do no harm) and "disturbances" means changes in the chemical composition of the air, and the events that cause such changes. So it doesn't literally mean that the disturbances are suppressed; it means that the detector's response to disturbances is suppressed if they are of a harmless kind. -------------------------------------------------- Note added at 7 hrs (2016-03-11 07:40:43 GMT) -------------------------------------------------- I should have emphasised that it says "known harmless disturbances". This refers to events that are known to occur and whose chemical profile is therefore known. The detector can be prepared to "ignore" these; its response can be suppressed when it detects their chemical profile. Of course, an unknown harmless disturbance could occur: an unexpected event for whose chemical profile the detector is not prepared but which may nevertheless be harmless and not indicate a fire. In those cases the response will not be suppressed and the detector will trigger the alarm, causing a false positive. However, these can be kept to a minimum. |
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