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In this paper, according to the theory and method of time-series analysis, the growing rings ARIMA model of wood properties variation pattern forLarix olgensis plantation was studied. The model recognition and parameter estimation were discused. The ARIMA model of wood growth ring density, growth ring widith and late wood percentage was obtained. Appling the ARIMA model which obtained from actual test fitted the variation pattern of wood growth ring forLarix olgensis. The result indicated it was an effective method that applied the ARIMA model to study wood growth ring properties variation pattern. By comparing with the actual variation pattern from test data the goodness of fit was good.

With adopting the Wavelet analysis theory, the adhesive distribution state on particle surface was studied during the particleboard manufacturing. Using the image processing method, the ratio of adhesive covering on the particle surface was measured. The image of Wavelet transform, marginal texture check and marginal texture characteristic parameters were obtained. This method was very useful to study the mechanism of particles gluing and to improve the quality of particleboard.

Basing on a lot of examinations, according to the fundamental image processing theories and methods, getting touch with the property of wood anatomical structure image, we put forward the optimum method and theory which are suitable for the binary processing of the wood anatomical structure image. After the wood image has been processed binary, with the help of computer vision technology, the boundary of wood anatomical structure molecular binary image was sought. This kind of theory and method lay a solid foundation on the collection of feature and the pattern recognition and other high level processing of wood anatomical structure molecular image.

The multinomial wood surface roughness parameters and wood color parameters of 5 kinds of species of trees were measured in working operation by the stylus surface roughness meter and colorimeter, and the measurement results were compared. The results indicated: The variations of wood surface roughness had the effect on the wood color of some kinds of species of trees on working operation, with the surface roughness decreasing, the brightness and luminance exponent increased, the hue angle increased lightly, but the variation of color saturation was different to the different wood color hue of species of trees.

In this paper, the heat tratment of wood samples of 8 tree species with different colour were made at different temperature and time. Using SC-1 Model colorimeter, the colorimetric parameter was measured at quantitative measuring for treatment fore-and-after wood samples color. The effect of heat treatment conditions on wood color was analyzed. The results indicated: the temperature and time of heat treatment affected on big extent for wood samples color, in which the heat temperature was more evident than others. The luminance index of wood color parameter was more sensitive to treatment condition, which it reduced with temperature and time increasing, this kind of variation tendency was the same as all wood samples, but the variations extent was more different among the different wood species. After heat treatment the wood color hue and saturation variation direction were different for different wood species. This phenomenon had the relation to the migration and volatilization of color extract in heating process, or the rapid oxidation of Iignin and some chemical element in high temperature.

This paper summarized the previous researches about resin efficiency of particleboard in the world, and introduced the computer vision (CV) technique on resin efficiency, which has the properties of high measuring speed, automatic pattern recognition and low environmental requirement, etc. The theory of the CV technique used for resin efficiency in particleboard was studied, along with the handling of resined-particle images and the gathering of relative gray image features. Some quantitative parameters describing the resin efficiency of particleboard were established, and the results indicated that the computer vision method on the resin efficiency was much better than others and can control the producing of particleboard more effect.

In this paper, the relationship was studied bwtween the permeability of Pinus koraiensis, Larix gmelinii, Betula platphylla and Populus davidiana and moisture content of wood in the hygroscopic range. The mathenatical model of variation low has been obtained from the relationship between wood and water, The results are as fellow: (1)The relationship betweed wood permeability and the moisture content is in twice curve function in the hygroscopic rang. (2)There is a peak value in tangential permeability, (3) The number of openings per cm of cross sectionand pit—opening average radii reduces by the increaasing of wood moisture content.

X-ray is irradiated in some wood composites (multi-layer particleboard, single-layer particleboard. reconsolidated wood,). According to the gray degree principle (0 –255 grade degree) and the corresponding relation between density and gray. X-ray negatives are scanned. The numbers and pictures of every degree density are obtained and accurate composite densities are counted.

In this paper, the permeable measurement equipment was made by authors. The permeability of four species of common wood was measured. These species grow in northeastern area of China. The results indicated that 1) The experiment proved this equipment was reasonble in structure, good measurement precision and convenient use, and the wood permeability measurement was satisfied. 2) Wood permeability was the physical property of anisotropy in different grain directions. The permeability of four kinds of wood in axialis are greater than that in crosswise, the permeability ofPinus koraiensis andLarix dahurica in radial is greater than that in tangential, and the permeability ofPopulus davidiana Dude andBetula platyphylla Suk in tangential is greater than that in radial 3) According to the data of four kinds of wood permeability in different grains direction, the effect mechanism on wood permeability and different properties was discussed and analysed.