The present disclosure provides reusable diaper devices, systems, and methods. The device includes a bearing surface on which a pile of pages is placed. An inner magnet holder frame attached to the outer casing wall holds a magnet to the conduit and is fabricated of non-ferrous stainless steel to allow maximum trans mission of the magnetic field to the fluid in the non-ferrous section of the conduit around which the casings are attached together. The output voltage from the shunt regulator is limited by the second feedback control loop to ensure that the output voltage does not exceed the maximum rated voltage of the battery. This is achieved by tagging security expressions as special and utilizing rules of predicate to pull or push non-security expressions above or below security expressions, depending on the likelihood of a non-security being safe, as determined via a static andor dynamic analysis. Also provided is a substrate-processing chamber with improved cleaning properties having a coil capable of being coupled with an RF field disposed at selected areas of the chamber.