Application Of Computed Tomography To Wood Testing

In the face of forest resource scarcity, it is urgent fairs to reasonably use, protect and develop available forest resource and improve wood utilization. Wood nondestructive technology is a new and comprehensive wood testing technology, which was dated from 1950s, and has gained fast development in the recent years. Nondestructive testing can quickly test wood properties by using contemporary advanced technologies and measuring methods in the precondition of nondestructive wood and woodiness shape, structure and dynamical posture.In the paper some kinds of often used wood nondestructive methods were compared with and valued, and finally computed tomography, which is a branch of radioactive testing method, was chosen as wood nondestructive testing method. Compared with conventional methods, the superiority and feasibility of CT testing were set forth in the practice application.After the introduction of CT imaging principle, 12 trees were scanned by CT system, and the best equipment parameters were calculated in the course of wood CT testing, which provided the dependence in the fast wood CT testing. Meanwhile, based on above data, CT number-wood density equation was fitted, which provided a new nondestructive testing method in fast wood density testing.Multifractal analysis has the result of good locality and globality. Aiming at the defects in the wood, firstly, the fractal features were highlighted after the filtering and equalization preprocessing in wood CT image. Then, different multifractal spectrum values were applied to detect the defects in the wood CT image. Many experiment results in the paper confirmed that multifractal theory was effective in wood defect testing. Compared with conventional methods—differential edge operators, Log operator and Canny edge operator, multifractal theory is a feasible and correct result in edge testing. Therefore, a new theory method in edge identifying and testing of wood CT image is proposed in the paper.