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A flame ionization detector (FID) is a scientific instrument that measures analytes in a gas stream. It is frequently used as a detector in gas chromatography . The measurement of ions per unit time makes this a mass sensitive instrument. [ 1 ]
Fault detection, isolation, and recovery (FDIR) is a subfield of control engineering which concerns itself with monitoring a system, identifying when a fault has occurred, and pinpointing the type of fault and its location. Two approaches can be distinguished: A direct pattern recognition of sensor readings that indicate a fault and an analysis ...
The detection limit for electron capture detectors is 5 femtograms per second (fg/s) and the detector commonly exhibits a 10,000-fold linear range. [ citation needed ] This made it possible to detect halogenated compounds such as pesticides and CFCs , even at levels of only one part per trillion ( ppt ), thus revolutionizing our understanding ...
The specificity of the test is equal to 1 minus the false positive rate. In statistical hypothesis testing, this fraction is given the Greek letter α, and 1 − α is defined as the specificity of the test. Increasing the specificity of the test lowers the probability of type I errors, but may raise the probability of type II errors (false ...
A DID is an ion detector which uses a high-voltage electric discharge to produce ions. The detector uses an electrical discharge in helium to generate high energy UV photons and metastable helium which ionizes all compounds except helium. [1] The ions produce an electric current, which is the signal output of the detector. The greater the ...
The method requires thorough cleaning of the inspected items. Inadequate cleaning may prevent detection of discontinuities. Test materials can be damaged if compatibility is not ensured. The operator or their supervisor should verify compatibility on the tested material, especially when considering the testing of plastic components and ceramics ...
Failure analysis is the process of collecting and analyzing data to determine the cause of a failure, often with the goal of determining corrective actions or liability.. According to Bloch and Geitner, ”machinery failures reveal a reaction chain of cause and effect… usually a deficiency commonly referred to as the symptom…”
A fault tree diagram. Fault tree analysis (FTA) is a type of failure analysis in which an undesired state of a system is examined. This analysis method is mainly used in safety engineering and reliability engineering to understand how systems can fail, to identify the best ways to reduce risk and to determine (or get a feeling for) event rates of a safety accident or a particular system level ...