Table 7. Increase in the magnitude (% relative) of the logarithmic decrement of damping with variations in different factors

Indicator Natural oak Stained oak
Rad. Tang. Rad. Tang.
Temperature (20°C–100°C) 7 6 6 9
Humidity (0%–40%) 37 31 41 10
Ultrasonic treatment (0–1,200 s) 41 34 37 11
Pulsed magnetic field treatment (0–120 s) 21 29 42 17
Rad.: radial, Tang.: tangential.