Cycle per second Cycle per second The cycle per second was a once-common English name for the unit of frequency now known as the hertz (Hz). The plural form was typically used, often written cycles per second, cycles/second, c.p.s., c/s, ~, or, ambiguously, just cycles. The term comes from the fact that sound waves have a frequency measurable in their number of oscillations, or "cycles", per second. With the organization of the International System of Units in 1960, the cycle per second was officially replaced by the hertz, or reciprocal second, "s" or "1/s". Symbolically, "cycle per second" units are "cycle/second", while hertz
Noise and vibration on maritime vessels throughout the ship. In most compartments, this type of vibration normally manifests itself as audible noise. The problem with diesels is that, for a given size, there is a fixed amount of power generated per cylinder. To increase power it is necessary to add cylinders but, when cylinders are added, the crankshaft has to be lengthened and after a very limited number of additions, the lengthened crankshaft begins to flex and vibrate all on its own. This results in an increase of vibrations spread all over the ships structure. Crankshaft vibration can be reduced by a harmonic balancer. Large vessels