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Cross-Sectional Image Reconstruction of Wooden Member by Considering Variation of Wave Velocities

Kim, Kwang-Mo   (Div.of Wood Performance, Dept. of Forest Products, Korea Forest Research InstituteCC0102761  ); Lee, Sang-Joon   (Dept. of Forest Science, College of Agriculture & Life Sciences, Seoul National UniversityUU0000691  ); Lee, Jun-Jae   (Dept. of Forest Science, College of Agriculture & Life Sciences, Seoul National UniversityUU0000691  );
  • 초록

    This study was performed as part of a research project aimed at developing an ultrasonic computed tomography (CT) system of wood for field application. In this reports, we investigate the variation of wave velocities on the cross section of real size wooden structural member to confirm the reason of image distortion on CT image of wood, and then proposed a new image reconstruction method by considering the velocity variation on wood cross section. First of all, the effect of wood anisotropy on ultrasonic velocities of wooden members was investigated. Based on the relationship between ultrasonic velocity and annual ring angle, which was obtained from test results of small clear specimens, ultrasonic velocities of each measuring angle were predicted. Next, they were compared with the ultrasonic velocities measured on five wood disks. There were very large differences between predicted and measured results, thought to be caused by the skewing effect of ultrasound and the presence of juvenile-wood. Based on these findings, a new method was proposed to reconstruct cross-sectional image of wood. By using this method, some distortions on reconstructed images could be removed, and defects were more easily and clearly detected. The minimum size of detectable defect was decreased remarkably, from 33 mm to 13 mm. However, the size of the detected defect was enlarged and the position somewhat shifted to the specimen surface on the CT images, which was also thought to be caused by the skewing effect of ultrasound. Additional research has been planned to solve these problems.


  • 주제어

    anisotropic characteristic of wood .   cross-senctional image .   ultrasonic TOF .   defect detection .   field application.  

  • 참고문헌 (14)

    1. Armstrong, J. P., D. W. Sneckenberger. 1991. Comparison of three equations for predicting stress wave velocity as a function of grain angle. Wood and Fiber Science 23(1): 32-43 
    2. Gerhard, C. C. 1980. Effect of cross grain on stress waves in lumber. Res. Pap. FPL-RP-368. Madison, WI: U.S. Department of Agriculture, Forest Service, Forest Products Laboratory. 8p 
    3. Kim, K. M. and J. J. Lee. 2005a. CT image reconstruction of wood by using ultrasound velocities I - Effects of reconstruction algorithms and wood characteristics. J. of the Korean Wood Science and Technology 33(5):21-28     
    4. Schmoldt, D. L., L. G. Occena, A. L. Abbott, and N. K. Gupta. 1999. Nondestructive evaluation of hardwood logs: CT scanning, machine vision and data utilization. Nondestructive Test and Evaluation 15: 279-309 
    5. Pharn, D. T. and R. J. Alcock. 1998. Automated grading and defect detection: a review. Forest Products Journal 48(4): 34-42 
    6. Lee, J. J., K. M. Kim, and M. S. Bae. 2003. Investigation of transmission process for ultrasonic wave in wood. J. of the Korean Wood Science and Technology 31(2): 31-37 
    7. Tamura, Y., K. Adachi, Y., Yanagiya, M. Makino, and K. Shioya, 1997. Ultrasonic Time-of-Flight Computed Tomography for Investigation of Wooden Pillars: Image Reconstruction from Incomplete Time-of-Flight Profiles. J. Appl. Phys, 36(5B): 3278-3280 
    8. Biernacki, J. M. and F. C. Beall. 1993. Development of an acousto-ultrasonic scanning system for nondestructive evaluation of wood and wood laminates. Wood and Fiber Science 25(3): 289-297 
    9. Adachi, K., Y. Tamura, S. Kanda, K. Shioya, and Y. Yamashita. 1999. Development of Ultrasonic Time-of-Flight Computed Tomography System for Structural Inspection of Buildings. Technical Report of IEICE, US99-9. The Institute of Electronics Information and Communication Engineers. pp. 7-14 
    10. Dickens, J. R., D. A. Bender, and D. E. Bray. 1996. A critical-angle ultrasonic technique for the inspection of wood parallel-to-grain. Wood and Fiber Science 28(3): 380-388 
    11. Kim, K. M. and J. J. Lee. 2005b. CT image reconstruction of wood by using ultrasound velocities II - Determination of the Initial Model Function of the SIRT Method. J. of the Korean Wood Science and Technology 33(5):29-37     
    12. Bucur, V. 1988. Wood structural anisotropy estimated by acoustic invariants. lAWA Bulletin 9(1): 67-74 
    13. Bucur, V. 2003. Nondestructive Characterization and Imaging of Wood. Springer, Germany, 354p 
    14. Han, S. R., C. Y. Park, I. C. Lee, and J. J. Lee. 2005. Studies about the effect factors on ultrasonic velocity of domestic red pine. Proceeding of International Symposium on Wood Science and Technology. pp. 149-150 

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