Abstract: The invention is a health monitoring system that determines the spine stress dose value for an individual on a high speed boat. The boat can produce impact injury from whole-body vibration embedded with multiple shocks. The system includes an RFID tag; a GPS; a display; a RFID reader; a multi-axis sensor unit that is an accelerometer which enables the determination of impact, vibration and shock, impact and vibration; and a central data acquisition apparatus. The apparatus includes processors in communication with the GPS, the sensor unit, and the RFID reader. The apparatus samples the RFID reader frequently, confirming the status of all individuals having RFID tags as being onboard or overboard. An application records a GPS location and time if an individual is overboard, and generates a course to the GPS location. The display illustrates a ride roughness graphically, in terms of injury potential at a particular speed and heading.

Abstract: A golf club head and a method of tuning the golf club head. The golf club head includes a body having a front surface, a back surface, a heel end, a toe end, a sole extending between the lower portions of the heel and the toe ends, a top portion extending between the upper portions of the heel and toe ends, and a cavity. One or more magnets are mounted in the cavity such that their distance into the cavity can be adjusted. A detachable face plate having one or more magnets attached to a back surface of the detachable face plate is slidably mated with guides extending from the body. At least two of the magnets are positioned such that the north pole of the magnet in the cavity faces the north pole of a magnet attached to the back surface of the detachable face plate. A repulsive force between the north poles pushes the detachable face plate away from the body and into a stop coupled to the body.