Abstract: System and methods are provided for three-dimensional simulation of a water environment in which one or more individuals are positioned in or around the water environment and then randomly presented in actual or potential distress situations. One embodiment includes means for presenting a random water environment with one or more random individuals presented in actual or potential distress situations, means for permitting a system user to call attention to when the one or more individuals are in an actual or potential distress situation, and means for detecting the response time from when the actual or potential distress situation begins to when the user calls attention to the one or more individuals in such an actual or potential distress situation.

Abstract: A metering device of the type in which a shuttle moves axially within a chamber between two terminal positions, with the chamber having fluid inlet and outlet at each end so that fluid may enter through one end to move the shuttle to cause fluid to be ejected through the other end, and vice versa. A control valve is provided to control the fluid flow, the control valve being a spool valve having a spool sealingly slidable within a bore, the spool valve being associated with a device to drive the spool between two alternate positions in response to the shuttle reaching each end of the chamber.