Another study will assess the impact of different frequencies of observations on teachers and whether teachers trained as observers also improve their own classroom practice. (educationbusinessuk.net)
The possibilities are not just academic — different «modes of vibration» are often associated with different frequencies of radiation. (hubpages.com)
For instance, two sounds that start at the same instant in time probably come from a single person, even if they involve several different frequency bands. (scientificamerican.com)