A tether bracket assembly for securing a connector of a child seat is used in conjunction with a seat assembly having an U-shaped seat back frame. The invention combines a mechanical tensioner device and buoyancy can to apply controlled tension to an individual riser or group of risers supported by a floating offshore structure. The delay unit receives an input signal and a voltage control signal, and outputs a delay signal. Following transmission of the first subframe to the second node, the second frame is transmitted to the second node prior to transmission of the second subframe to the second node. A hydrocarbon feed stream and a catalyst travel through a first section of the riser at a first velocity of between about 1.