<acronym id="a2sgq"></acronym>
<acronym id="a2sgq"><center id="a2sgq"></center></acronym><acronym id="a2sgq"><center id="a2sgq"></center></acronym>
<acronym id="a2sgq"></acronym><rt id="a2sgq"></rt>
<acronym id="a2sgq"><small id="a2sgq"></small></acronym>
<acronym id="a2sgq"><small id="a2sgq"></small></acronym>
<acronym id="a2sgq"><small id="a2sgq"></small></acronym>

A microwave method for measuring moisture content, density, and grain angle of wood

The attenuation, phase shift and depolarization of a polarized 4.81-gigahertz wave as it is transmitted through a wood specimen can provide estimates of the moisture content (MC), density, and grain angle of the specimen. Calibrations are empirical, and computations are complicated, with considerable interaction between parameters. Measured dielectric parameters, however, correlate uniquely and repeatably with MC over a range of MC at least as great as 100 percent of the dry weight of the wood. Grain angle can be deduced reliably when the specimen thickness and MC are great enough to introduce sufficient dielectric anisotropy to appreciably depolarize the incident wave. At present, the apparatus and techniques are very complex, but the principles developed by this research show the method to be feasible for nondestructive testing of lumber as it is produced.
This article is in PDF format (file size: 127 kb). To download this article, right click on the link immediately below and choose "save target as". To view the article, left click the link immediately below.
(Download the latest Acrobat Reader if required.)

A microwave method for measuring moisture content, density, and grain angle of wood   ( )

The attenuation, phase shift and depolarization of a polarized 4.81-gigahertz wave as it is transmitted through a wood specimen can provide estimates of the moisture content (MC), density, and grain angle of the specimen. Calibrations are empirical, and computations are complicated, with considerable interaction between parameters. Measured dielectric parameters, however, correlate uniquely and repeatably with MC over a range of MC at least as great as 100 percent of the dry weight of the wood. Grain angle can be deduced reliably when the specimen thickness and MC are great enough to introduce sufficient dielectric anisotropy to appreciably depolarize the incident wave. At present, the apparatus and techniques are very complex, but the principles developed by this research show the method to be feasible for nondestructive testing of lumber as it is produced.

Author: James, W. L.; Yen, Y.-H.; King, R. J.


Source: (Research note FPL ; 0250):9 p. ; 28 cm.

Citation: James, W. L.; Yen, Y.-H.; King, R. J.  .  A microwave method for measuring moisture content, density, and grain angle of wood   (Research note FPL ; 0250):9 p. ; 28 cm..
人妻少妇精品视频一区