| NRC |
Manages registrations for Prometric Testing Center exams delivered outside of the US
출처: www.prometric.com/PressRoom/KnowledgeCenter/Glossa...
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| NRC |
A measure of the acoustical absorption performance of a material, calculated by averaging its sound absorption coefficients at 250, 500, 1000, 2000 Hz, expressed to the nearest multiple of 0.05.
출처: www.aeromfg.com.au/html/immotus_-_reference_materi...
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