Abstract: A moisture content measuring system for sheet material which uses microwave radiation. Two pairs of microwave radiators and receivers are combined with surface and below surface temperature measuring sensors to furnish data to a computer which interprets the data and yields moisture readings. Each pair of microwave radiator and receiver straddles the sheet test sample and checks microwave transmission through the sample and reflected from it, but the two radiators are cross polarized so that signal interchange between them is avoided.

Abstract: An apparatus for testing the friction and susceptibility to damage by casters of various floor materials. A sample of floor material is moved under a caster wheel by a moving table. The caster orientation, pressure and size are variable. Forces on the caster are monitored by instruments which also read the reaction of the floor sample to the test. Records are produced both in tabular and in graphic form.

Abstract: An optoelectronic scanning device comprising two sets of photoresponsive elements adjusted to operate at different detection levels and aligned to scan materials marked with luminous paint and illuminated with ultraviolet light. The photo-elements are specially aligned to be optically responsive over an array of contiguous in-line domains and are coupled to trigger circuits to provide snap-action operation. The photo-elements and associated electrical components are heated and maintained at a constant temperature to ensure stable operation of the device.