[IEEE 2016 IEEE NW Russia Young Researchers in Electrical and Electronic Engineering Conference (EIConRusNW) - Saint Petersburg, Russia (2016.2.2-2016.2.3)] 2016 IEEE NW Russia Young Researchers in Electrical and Electronic Engineering Conference (EIConRusNW) - Assessment of security of confidential information from leak on the acoustic and vibroacoustic channel on the basis of definition and calculation of coefficient of noise contamination and octava coefficient of noise contamination