Abstract: An air delivery system comprises a visor having an outer peripheral edge and an inner peripheral edge. An air filtration assembly is removably mounted above an opening in the visor between the outer and inner peripheral edges, the air filtration assembly comprising a fan having an air inlet and an air outlet, an anode layer disposed over the air inlet, a filter layer disposed over the anode layer and a cathode layer disposed over the filter layer. In a first configuration, the air filtration assembly provides air flow toward an inner surface of the visor and, in a second configuration, the air filtration assembly provides air flow away from an outer surface of the visor. The air filtration assembly includes a mode actuator configured to control operation of a filtration mode indicator in dependence upon positioning of the air filtration assembly in the first or second configuration.

Abstract: A method for memory reclamation for object-oriented program-controlled systems with real-time constraints. Resource reclamation, commonly called garbage collection, in object-oriented systems is segmented into discrete, real-time bounded segments. Scheduling of the segments is controlled so that garbage collection is unobtrusive to the system, while memory resources are reclaimed at approximately the same rate as they are allocated. Objects referenced from other objects are checked via an incremental mark/sweep method. Objects referenced from stacks are also accounted for. If a stack cannot be swept for object references in one real-time segment, the stack is copied into a save area and swept during one or more subsequent real-time segments.

Abstract: In object-oriented systems, non-memory resources are both managed by objects and represented as objects. If an object managing or representing non-memory resources becomes unreferenced, the non-memory resources managed by that object are lost from the system. This invention provides, as a part of a garbage collection process that automatic recovers memory resources of unreferenced objects, a last-will method that is invoked for unreachable objects that have provided a method named "finalize." All unreachable objects that have a last will method are put on a list. A separate process is scheduled to run each last-will method on its object in the list. Objects that have become reachable as a consequence of the last-will method are preserved. The memory resources associated with objects that have remained unreachable after the execution of the last-will method are recovered. In this way both memory and non-memory resources are preserved for re-use.

Abstract: A fault recovery method for a distributed processing system where a message called a heartbeat is broadcast among the processors once during each major processing cycle. The heartbeat message indicates the physical and logical identity of the transmitting processor with respect to the system arrangement as well as the processor's present operational state. By monitoring the heartbeats from other processors, spare processors can autonomously take over the functions of failed processors without being required to consult or obtain the approval of an executive processor. The new physical location of a replaced processor will be automatically recorded by the other processors. The method has application to duplex standby and resource pool configurations as well as sparing arrangements.