AUTOMATED LOW-ENERGY PHOTON-ABSORPTION EQUIPMENT FOR MEASURING INTERNAL MOISTURE AND DENSITY DISTRIBUTIONS OF WOOD SAMPLES

Automated equipment for measuring the moisture and density distributio ns of wood samples was developed. Using a narrow beam of gamma rays, t he equipment scans the wood samples, which are placed on the moving be lt. The moisture measurement is based on the Am-241 photon absorption technique (59.5keV), where the difference of the linear absorption coe fficients of the moist and dry wood is measured. The method requires n o knowledge of the thickness of the specimen. The density estimation m ethod is based on the measurement of the linear attenuation coefficien t of wood. Comprehensive software including image processing was devel oped for treatment of the numerical values of the measurements.