A dry powder inhaler has a dispersion chamber containing beads. The method comprises receiving the list of newly found elements and deriving a potential key value for a portion of the newly found elements from configuration data associated therewith and a key format. The job manager includes at least one state, or service object that represents a service or process to be performed on a print job. These observer notifications need only be sent for objects that are actually being observed but are related objects, substantially reducing the performance overhead of needless invocations of the observer notifications without limiting binding between objects. The present disclosure further includes a method of manufacturing semiconductor devices, especially for a singulation process. The system can be located on chip.