An apparatus for controlling a level of oxygen in a closed environment from an oxygen supply having an oxygen sensor for detecting the level of oxygen in the closed environment. The apparatus has a plurality of relays in communication with the sensor. The apparatus has a valve in communication with the relays and the oxygen supply which is automatically opened with the relays without human interaction, monitoring and adjustment to release oxygen from the oxygen supply into the environment when the level of oxygen in the environment goes below a first predetermined level and which is automatically closed with the relays without human interaction, monitoring and adjustment to stop oxygen from being released from the oxygen supply into the environment when the level of oxygen in the environment goes above a second predetermined level. A method for controlling a level of oxygen in a closed environment from an oxygen supply. A refuge chamber.

Lightweight shielded enclosures and systems provide a high level of acoustic, RF, EMI and EMP protection. Such enclosures and systems include one or more lightweight, non-conductive beams arranged to support a shielded covering.

Lightweight shielded enclosures and systems provide a high level of acoustic, RF, EMI and EMP protection. Such enclosures and systems include one or more lightweight, non-conductive beams arranged to support a shielded covering.

A nuclear reactor seismic isolation assembly includes an enclosure that defines a volume; a plastically-deformable member mounted, at least in part, within the volume; and a stretching member moveable within the enclosure to plastically-deform the plastically-deformable member in response to a dynamic force exerted on the enclosure.

A self-centering cable includes a restoring and energy-dissipation unit and a cable reinforcement connected to the restoring and energy-dissipation unit by a connecting unit. The restoring and energy-dissipation unit includes an outer trough, an axial tube provided in an opening at the upper end of the outer trough, two inverted U-shaped mild steel members provided side by side and fixedly mounted in the outer trough, an axial pallet sandwiched between and fixedly connected to the two inverted U-shaped mild steel members, and a disc spring set provided in the outer trough and sleeved onto the axial tube. The cable reinforcement includes a tensile reinforcement penetrating into a reinforcement bottom connector and a reinforcement top connector. The reinforcement bottom connector is connected to the axial tube, the top end connector, connected to the reinforcement top connector, and a bottom end connector are connected to a structure to be reinforced.

A self-centering cable includes a restoring and energy-dissipation unit and a cable reinforcement connected to the restoring and energy-dissipation unit by a connecting unit. The restoring and energy-dissipation unit includes an outer trough, an axial tube provided in an opening at the upper end of the outer trough, two inverted U-shaped mild steel members provided side by side and fixedly mounted in the outer trough, an axial pallet sandwiched between and fixedly connected to the two inverted U-shaped mild steel members, and a disc spring set provided in the outer trough and sleeved onto the axial tube. The cable reinforcement includes a tensile reinforcement penetrating into a reinforcement bottom connector and a reinforcement top connector. The reinforcement bottom connector is connected to the axial tube, the top end connector, connected to the reinforcement top connector, and a bottom end connector are connected to a structure to be reinforced.

A self-centering cable includes a restoring and energy-dissipation unit and a cable reinforcement connected to the restoring and energy-dissipation unit by a connecting unit. The restoring and energy-dissipation unit includes an outer trough, an axial tube provided in an opening at the upper end of the outer trough, two inverted U-shaped mild steel members provided side by side and fixedly mounted in the outer trough, an axial pallet sandwiched between and fixedly connected to the two inverted U-shaped mild steel members, and a disc spring set provided in the outer trough and sleeved onto the axial tube. The cable reinforcement includes a tensile reinforcement penetrating into a reinforcement bottom connector and a reinforcement top connector. The reinforcement bottom connector is connected to the axial tube, the top end connector, connected to the reinforcement top connector, and a bottom end connector are connected to a structure to be reinforced.

Disclosed is a fireproof shutter for opening and closing a passage between an upper story and a lower story. The fireproof shutter includes a base panel having an opening corresponding to the passage, a door for opening and closing the opening, and a guide unit for guiding the door between an open position in which the door is opened and a closed position in which the door is closed and having a predetermined inclination such that the door is closed by its own weight.

This disclosure relates to systems, methods, and apparatuses for providing security at sites to protect against active shooter situations and other dangerous threats. In certain embodiments, a security system comprises one or more security boxes that are in communication with an electronic security platform. The security boxes house equipment that can be utilized by individuals to protect themselves against security threats and to secure their immediate location. The security boxes also include various electronic components that enable detecting security threats and communicating with the electronic security platform.

This disclosure relates to systems, methods, and apparatuses for providing security at sites to protect against active shooter situations and other dangerous threats. In certain embodiments, a security system comprises one or more security boxes that are in communication with an electronic security platform. The security boxes house equipment that can be utilized by individuals to protect themselves against security threats and to secure their immediate location. The security boxes also include various electronic components that enable detecting security threats and communicating with the electronic security platform.