Through set sequence is resolved into finite mutually disjunct subsets, the new method to solve the limit superior and limit inferior of set sequence is give.

If the diesel engine has a superior economic performance, a dependable work, and if the noise and the vibration can be controlled in a lower limit, which usually depends upon its valve train system.

It is meanwhile good practice to limit performance metrics to as few as possible, and the carbon footprint does not belong on the list when far superior techniques are available.