Abstract: A fluid-driven pump directly converts fluid kinetic energy into displacement of a second fluid against a pressure differential. In one form of the invention, a wind turbine is coupled via a rotary shaft crank to a reciprocating piston in a large-displacement, double-acting compressor cylinder. In a preferred mode, a refrigerant gas is compressed to accomplish heat pumping and refrigeration. Timed compression-relief valving controls the time that the wind turbine is coupled to the fluid load to maintain maximum power transfer within useful operating limits of source and load. An electronic control circuit senses selected parameters to compute the desired duty cycle and provide an energizing signal to a pair of solenoid relief valves such that the optimum duty cycle is selected for maximum power transfer.

Abstract: Apparatus and method for continuously monitoring the fetal heart rate simultaneously using ultrasonic and electrocardiographic signals. The signals are continuously processed to provide an improved output fetal heart rate indication in terms of better continuity and accuracy.

Abstract: Mating fasteners having a convex receiving surface and a concave inserting surface rotationally symmetrical about an insertion axis. A key code of annular projections and grooves is located in a plane normal to and concentric with the insertion axis. A locking mechanism engages the mating pieces only when in mating relation as determined by the key code. A planar embodiment is included. Easy and accurate assembly or connection becomes much less critical.