Improvement of Wood CT Images by Consideration of the Skewing of Ultrasound Caused by Growth Ring Angle

Authors

  • Kwang-Mo Kim
  • Jun-Jae Lee
  • Sang-Joon Lee
  • Hwanmyeong Yeo

Keywords:

Ultrasonic wave, computed tomography (CT), transmission path, skewing effect, wave refraction, juvenile wood

Abstract

For the purpose of removing distortions in ultrasonic computerized tomographic (CT) images of wood, this study proposes a technique for taking into account the skewing effect in reconstructing the image. First, it was experimentally confirmed that an ultrasonic wave is refracted because of the anisotropic characteristics of wood. Transmission paths of an ultrasonic wave through a cross-section of wood were predicted by considering the change in wave velocity based on the annual ring angle and the presence of juvenile wood. Then, the methodology of the application of the predicted paths to CT image reconstruction was proposed and verified. The accuracy of defect detection in wood was significantly improved by the proposed technique.

References

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Published

2008-11-03

Issue

Number 4 / October 2008

Section

Research Contributions

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