A storage system is configured to create and manage virtual ports on physical ports. After connecting from the multimode fiber to a single-mode fiber, the optical signal is branched by a SMF coupler, and the intensity of the optical signal after the connection by a SMF monitor PD is detected. Also, the converting may comprise exposing the electrodeposited material to a nitrogen-comprising plasma. The achieved coefficients and the output of the sensor are substituted into the quadratic equation to calculate the actual physical quantity. The method includes the steps of: calculating belt displacement transversely to the belt length at or near a first location at which teeth on the belt mesh with teeth on a first cooperating toothed pulley; calculating a belt fluctuation velocity by correlating the belt displacement to a time frame; and calculating a radiated sound pressure level using the belt fluctuation velocity.