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云南松、华山松是西南地区的主要用材树种。为了研究林木密度与林木生长之间的关系,更好地经营管理好云南松林和华山松林,在引进国内外编图的理论和方法的基础上,我们编制了滇中地区、南盘江林区的云南松和广元林区的华南山松人工林林分密度管理图。按典型选样法所设置的样地,基本能代表该地区云南松和华山松的生长情况,其中,滇中地区云南松林内设置样地493块,南盘江林区云南松林内设置样地305块,广元林区华山松林内设置样地252块。本文不仅在数据惧和整理方法上做了说明,而且以数表的形式了说明了数学模型的选择以及最大密度线、等树高线、等直径线、等疏密度线和自然稀疏线的绘制方法。成图后进行了理论和适用精度检验,其理论精度均在91%以上,适用精度均在85%,证明本设计适用于该林区。该图可用于抚育间伐、资源清查、生长量预测及造林设计等。 相似文献
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There are several studies related with knitted fabric containing elastomeric yarn. These studies have been carried out only
on fabrics containing naked elastomeric yarn, i.e., without intermingling. And most of them have focused on dimensional and
extension-recovery properties of the fabric. Of course, intermingling yarn parameters such as number of knots and draw-ratio
will affect the properties and performance of the fabrics. This paper presents a study about the effect of draw-ratio and
number of knots, which are important parameters in intermingled nylon-elastomeric yarns, on the physical and comfort properties
of hosiery knit products. To see the relationship and significance, bivariate correlation analysis and analysis of variance
have been carried out. It has been seen that increase of draw ratio and number of knots lead to an increase in dimensional
change, stitch density, fabric weight, and lead to a decrease in fabric spirality, abrasion, fabric wicking (wickability in
course direction is less than that of wale direction). Fabric thickness increases with an increase in draw ratio and a decrease
in number of knots. The number of knots and the draw-ratio do not affect the fabric drying rate. However, an increase in the
draw ratio and the number of knots result in an increase in initial water content before beginning the drying process. But,
an increase in initial water content is not so high as to affect the drying rate. 相似文献
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概述了日本文化财登录制度,结合中国近代文化遗产制度的构建,从中寻找中国文化遗产制度的不足,比较中日文化遗产制度,归纳出日本的文化财登录制度的两点优势。为中国遗产保护制度指明了努力的方向。 相似文献
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[目的]研究卷烟抽吸口数与7项卷烟常规物理指标的相关性.[方法]采用相关分析和通径分析探讨了卷烟抽吸口数与7项常规物理指标(烟支重量、圆周、总通风率、滤嘴通风率、纸通风率、开吸阻和闭吸阻)的关系,并探讨这些影响因素的交互作用和作用机理.[结果]分析表明,7项常规物理指标中,卷烟主要通过烟支重量(水松纸打孔与不打孔共有)和滤嘴通风率(仅水松纸打孔卷烟)的直接作用,纸通风率和闭吸阻的间接作用对抽吸口数产生正向效应;通过调控7项常规物理指标控制抽吸口数从而调控焦油,主要通过控制卷烟烟丝重量和水松纸透气度的稳定性来实现.[结论]在卷烟加工过程中严格控制烟支重量和滤嘴通风率这2项指标,一定程度上能稳定卷烟抽吸口数和焦油量. 相似文献
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