Abstract: Space frames incorporating flanged chords and struts with receiving spaces configured to receive at least portions of the chord flanges without the need for connector nodes that are separate from the chords. For example, a space frame can include a strut, a first chord, and a second chord. The first chord can have a first flange and a second flange fixed relative to the first flange. The second chord can have a third flange. The strut can include receiving spaces configured to receive portions of the first flange and the third flange. The strut can be secured relative to the first and second chords and the space frame can support a reflective surface configured to focus electromagnetic radiation.

Abstract: A service window may be operated under hands free user remote control. For example, a service window of the type used in fast-food restaurants, may be opened or closed in response to remote control signals.

Abstract: A remotely releasable security system for securing a barrier across a window opening to prevent unauthorized access to the interior of a building via a window, and to permit removal of the barrier for escape in an emergency or for maintenance. The security system includes a security barrier, a locking mechanism for securing the barrier to a window frame, a radiant energy receiver operably connected to the locking mechanism, and a radiant energy remote control transmitter for signaling the receiver to release the locking mechanism so that the barrier may be removed.

Abstract: A service window may be operated under user audio control. For example, a service window, for example of the type used in fast-food restaurants, may be opened or closed in response to a user voice command.