9 Nautical and optical apparatus and instruments, namely, accelerometers, wave gauges, bending moment sensors, sensors for measuring green water on ship deck, gyrocompasses, gyroscopes, motion reference units, wind and draught sensors, optical frequency metrology devices; apparatus and instruments for weighing, measuring, signaling, checking, life saving and teaching, namely, meteorological instruments, sensing and signaling devices for dynamic positioning of ships, and for measurement of ship hull motion and acceleration, current sea state and wave motion, green water on ship deck, parametric roll, and ship hull load; blank magnetic data carriers and blank optical discs; computers; computer programs for use in dynamic positioning of ships and for real time onboard ship heavy weather decision support, monitoring of ship behavior and heavy sea navigation; downloadable software for use in dynamic positioning of ships and for real time onboard ship heavy weather decision support, monitoring of ship behavior and heavy sea navigation; data processing apparatus, namely data processors; navigation apparatus and instruments, namely, global positioning system (GPS), programmable logic controller (PLC), computer, computer software, transponder, transducer, transmitters, receivers, interfaces for computers, and interfaces for detectors