Methods to determine the durability and wear-resistance of soft armor. Strain applied to the fiber optic laser results in an emission wavelength shift. A seal member is interposed between the transmission case and the outer circumferential edge of the flange portion at least in the range below the differential ring surrounding portion. The electric circuit exhibits at least one branch including an electric energy bank and a thyristor, which are connected in series with the motor winding. Seals are mounted into mounting holes perforated to form the water guides. The method also includes adjusting a cranial nerve stimulation parameter based on the sleep cycle information.