Abstract: Apparatus performs active, dynamic balancing of a rotating machine by shifting the spatial distribution of an inertial liquid within a body that co-rotates with the rotating shaft of the machine. The body includes chambers, substantially disposed at equal angular intervals, for containing the inertial liquid. The chambers communicate through a channel lying at or beyond the outermost radial position of the outward ends of the chambers. A motive element or elements are provided for impelling the inertial liquid through the channel. The chambers, channel, and motive elements form a sealable system.

Abstract: Heat generated from electronic equipment packed densely on a circuit board is transferred to conductive partition plates located adjacent to and on opposite sides of the circuit board. Heat is then transferred from the partition plates to conductive shelves located above and below the partition plates and then to a conductive rear wall of a cabinet. Heat is then transferred through the rear wall to a plurality of external fins and then to the atmosphere by radiation and convection. Alternatively, the circuit boards are housed in sealed enclosures. A clamp, fastened to the rear wall of the cabinet, is used for securing the sealed enclosure and for transferring the heat from the electronic equipment to the rear wall.