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生长轮密度
    THE ESTABLISHMENT AND PREDICTION OF THE DYNAMIC VARIATION MODEL OF WOOD GROWTH RING DENSITY FOR THE PLANTATION FOREST OF PINUS KORAIENSIS
    人工林红松木材生长轮密度动态模型建立与预测
    Study on Wood Microfibril Angle and the Correlation Models with Growth Ring Density of Ginkgo
    银杏木材微纤丝角及其与生长轮密度相关模型的建立
    Secondly, according to the forecasting methods applied widely nowadays, the most typical characteristic index of wood properties, namely, ratio of length/width of trachied and growth ring density, were selected as analytical data. The feasibility of wood properties forecasting model were established by the methods of linear regression, time series, and neural network and its forecasting precision were compared and proof-tested.
    其次,针对目前广泛采用的预测方法,选取人工林落叶松木材管胞长宽比和生长轮密度两项指标作为基础数据,采用回归分析方法、时间序列方法和神经网络方法分析建立木材材质预测模型的可行性,比较预测模型的预测相对误差和预测精度,并进行模型检验。
    The property indexes of physical and anatomical characteristics of planted Scotch pine in different aspects have significant difference in the radial directional variation, such as the growth ring width, the earlywood width, the latewood width, the growth ring density, the earlywood density, the latewood density, the earlywood tracheid length, earlywood tracheid wall thickness, latewood tracheid wall thickness, the earlywood tracheid radial diameter, the latewood tracheid radial diameter, the latewood cell wall percentage, the earlywood wall/lumen, the latewood wall/lumen and the resin canal percentage.
    不同坡向人工林樟子松物理和解剖特征各项指标中生长轮宽度、早材宽度、晚材宽度、生长轮密度、早材密度、晚材密度、早材管胞长度、早材管胞壁厚、晚材管胞壁厚、早材管胞径向直径、晚材管胞径向直径、晚材胞壁率、早材壁腔比、晚材壁腔比、树脂道组织比量径向变异差异显著。
    According to the theory and method of time-series analysis, the growth rings ARIMA model of wood properties variation pattern for Larix olgensis H. plantation was studied, the model recognition and parameter estimation was discussed, the ARIMA model of wood growth ring density, growth ring width and late wood percentage was obtained.
    采用时间序列分析理论,分析了人工林长白落叶松木材生长轮材性变异规律,对木材的生长轮密度、晚材率和生长轮宽度进行变异规律的拟合,并对建模方法、模型参数选择以及检验进行讨论。
    There are significant effects for thinning intensity on growth ring width, late wood percentage, growth ring density and hardness of Fraxinus mandshurica .
    对生长轮宽度、晚材率、生长轮密度、木材硬度有显著影响 ;
    The variation patterns of tracheid morphology and density of Pinus densiflora plantation were studied in this paper. The mathematical models of the variation pattern of tracheid length, tracheid diameter, ratio of tracheid length and width and growth ring density were obtained, which can provide the theoretical base for man-made forest intensive management and oriented cultivation as well as the early forecast of wood quality.
    研究分析了人工林赤松木材管胞形态和密度的变异规律 ,得出了管胞长度、管胞直径、管胞长宽比和生长轮密度等材性指标的变异规律的数学模型 ,为实现林木定向培育和速生优质制定科学集约经营措施以及材质的早期预测提供科学的理论依据
    The results showed that the variances of growth percentage, growth ring width(except pruning), growth ring density(except slope aspect and pruning) were remarkable, and the variance of latewood percentage(except pruning) was not significant.
    结果表明 :不同的森林培育措施 (坡位、林分结构、初植密度、间伐 )对红松人工林的生长率、生长轮宽度及生长轮密度有显著的影响 ,对晚材率的影响不明显 ;
    The neural network model of wood growth ring density was established, the variation discipline of wood growth ring density was simulated, and the fore cast of wood growth ring density was made. The advantages of the neural network model for wood growth ring density were demonstrated, which would provide a new method for the forecast of wood properties.
    建立了木材生长轮密度的神经网络模型,拟合了木材生长轮密度的变异规律,对木材生长轮密度进行了预测,并与时间序列方法对比,说明了神经网络用于木材生长轮密度预测的优势。
    The tracheid length, growth ring width, growth ring density and latewood percentage of the wood from Pinus koraiensis plantations and natural forests were tested by using optimum method of classification. The result showed that the boundary lines of juvenile wood and mature wood of planted and natural Pinus koraiensis were the 15 th year and the 35 th year respectively.
    根据人工林和天然林红松的管胞长度、生长轮宽度、生长轮密度和晚材率等性能指标的测试结果,采用最优分割法分析得出:人工林红松幼龄材与成熟材的界限为15a,天然林红松幼龄材与成熟材的界限为35a。
 

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