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    { "id" : "http://dbpedia.org/resource/Frequency_standard"
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        "http://www.w3.org/2000/01/rdf-schema#comment" : [ "A frequency standard is a stable oscillator used for frequency calibration or reference. A frequency standard generates a fundamental frequency with a high degree of accuracy and precision. Harmonics of this fundamental frequency are used to provide reference points.Since time is the reciprocal of frequency, it is relatively easy to derive a time standard from a frequency standard." ] ,
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