Abstract: A Forward Propagation Architecture is a novel switch architecture based on well-known unicast switching architectures, and provides two desirable properties: (1) no rearrangement of established calls is ever required and (2) the architecture is strictly non-blocking for multicast, even when multicast destinations are dynamically added to existing calls. These properties (excluding dynamic multicast destination addition) can be provided by standard architectures or Time:Space:Time architectures with speedup proportional to the width of the widest multicast to be supported. The speedup required by the FPA is constant and practical (approximately 4× speedup) and at significantly less hardware cost than n2 architectures. The key to the FPA's capability is a sequentially doubled fabric with a feedback loop. The FPA requires a routing algorithm for connection setting. The connection-setting algorithm is sufficiently simple to be implemented in hardware.

Abstract: A temporary vehicle door check mechanism suitable for use during vehicle painting operations comprises a hinge comprising door side and body side portions, and an intermediate bridge portion, all of which are rotatably connected at a common axis of rotation. A flexible prop button is mounted to either the door side or the body side portions of the hinge, and is adapted to releasably contact the intermediate bridge portion of the hinge as the door is rotated about the hinge, to releasably hold the door in a partially or fully open position.