A window assembly including a permanent frame portion, a removable frame portion, and a glazing panel sandwiched between. In one embodiment, the side shield is inclined with respect to the film plane to suppress the generation of a magnetic pole in the end portion of the side shield. Manipulation and storage tool generally includes a manipulation assembly which is movably mounted with respect to a guide assembly. Moreover dynamic exception handling is not operating system dependent. The nozzles on the front side and the rear side of the traveling route of the aeration device produce different counterforce.