System design means that the professional technologists conduct structure design on products of some kind according to their professional knowledge . the parameter design aims that the steady design scheme which is not disturbed by inside and outside factors could be found by studying general fluctuation produced by inside and outside interference , when controllable factors disturbing quality speciality of products change greatly , acceptance to lerance design is to make sure the calculation method of acceptance tolerance after confirming the central value of each parameter
मोबाइल