Abstract: A gear reduction unit for coupling the output member of a prime mover to the input member of a device that is to be driven thereby. The gear reduction unit includes an input shaft, an output shaft, a primary gear set arranged between the input shaft and the output shaft, a secondary gear set arranged between the input shaft and the output shaft, and a gear selection device. The gear selection device is configured to selectively and alternately couple the input shaft to the output shaft for driving thereof by one of the primary gear or the secondary gear set.

Abstract: Rapid, positive identification in a wide variety of lighting and visibility conditions is a must in combat and rescue operations. With modern imaging technology, both thermal and infrared radiation can be made visible to the human eye. By combining shape, color, heat, and infrared reflectivity, easily identifiable symbols can be made to be placed on vehicles, buildings, runways, landing pads, and personnel and can be made to be visible in all kinds of lighting. To be visible using thermal imaging technology, such symbols must have a temperature that is different from their surroundings—either colder or hotter. Symbols can be heated using resistance heat, by passing a hot fluid through a panel that makes up the symbol, or from an exothermic chemical reaction. Symbols can be cooled using a cold fluid passing through a panel, or an endothermic chemical reaction. A thermal radiation reflecting sleeve or envelope can be fitted over the heated panel.