Note that while the plural of KOS is KOSs, this can be difficult to read, so when possible you should rewrite the sentence in a different way. E.g. ``Each KOS'' or ``Several Knowbot Operating Systems''.
Note that while the plural of KSS is KSSs, this can be difficult to read, so when possible you should rewrite the sentence in a different way. E.g. ``Each KSS'' or ``Several Knowbot Service Stations''.