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Journal of Microwave Power
and Electromagnetic Energy (JMPEE) |
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TITLE |
Microwave Instrument
for Accurate Moisture and Density Measurement Timber [PDF] |
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AUTHORS |
M. Tiuri, K. Jokela and S. Heikkila 1980 15 4 251-254 |
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Abstract A new instrument for accurate
moisture and density measurement of timber is described. To determine the
optimum frequency the dielectric properties of Finnish spruce and pine have
been measured over the frequency range 100 MHz to 10 GHz. In the developed
instrument the attenuation of timber is measured at 10 GHz, the density is
determined by y-ray attenuation and the temperature by an infrared detector.
A microprocessor calculates the moisture content and the density. In a field
test the correlation coefficient between the moisture content determined by
the instrument and that measured directly was 0.993. The standard deviation
of the moisture content was 0.68%. |
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