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特殊外形孔的直径测量和测量结果的不确定度评定
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作者 刘小红 宋国斌 《计量与测试技术》 2008年第5期43-44,共2页
本文就我们对特殊外形孔的直径进行公正测量所选用的测量方法,使用的测量工具和测量结果的不确定度评定进行介绍。
关键词 特殊外形孔的直径 内径千分表 测长机 量块 测量不确定度
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磁记录档案保护技术刍议
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作者 罗备针 《云南档案》 1997年第2期33-34,共2页
新型档案材料在档案部门已广泛使用,其中,人们一般将已记录有各种档案信息的计算机磁盘等称之为磁记录档案.在目前市场上,磁盘的品种很多,购买时要特别注意从档案的安全保管角度来选择,要挑选质量稳定、可靠的产品.磁盘一般的外形直径... 新型档案材料在档案部门已广泛使用,其中,人们一般将已记录有各种档案信息的计算机磁盘等称之为磁记录档案.在目前市场上,磁盘的品种很多,购买时要特别注意从档案的安全保管角度来选择,要挑选质量稳定、可靠的产品.磁盘一般的外形直径有14英寸、8英寸、5.25英寸和3.5英寸,常用的是后两种,各自的存贮容量不尽相同.各档案使用部门的进货渠道、生产的厂家也不相同,为了达到存档保护的目的,除选择质量好的名牌产品外。 展开更多
关键词 档案保护技术 磁记录 档案目录中心 档案信息资源 使用方法 读写孔 档案管理人员 外形直径 计算机磁盘 保护工作
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Biomass growth characteristics of 13-year-old Pinus densiflora S.et Z.in a post-fire plantation on different contour conditions in Samcheuk,Korea
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作者 Lee Ju-Hyoung Lee Do-Hyung +2 位作者 Kim Do-Hyun Park Jin-Hwa KimJae-Hee 《Journal of Mountain Science》 SCIE CSCD 2016年第7期1238-1244,共7页
We used preliminary data to estimate the growth volume of artificially reforested Pinus densiflora in a post-fire area on three different contour conditions. We compared the growth of P. densiflora on a south-facing s... We used preliminary data to estimate the growth volume of artificially reforested Pinus densiflora in a post-fire area on three different contour conditions. We compared the growth of P. densiflora on a south-facing slope(Ssth), north-facing slope(Snth) and ridge area(Ridge), using 7 trees selected from each stand aspect. The tree height, diameter and growth volume were measured and the dry weight of each plant part were compared and analyzed. The results revealed that the total dry weight was highest on Ssth(5992.3 g), followed by Snth(4833.2 g) and lowest on Ridge(3160.1 g). The height growth was highest on Snth(285.8 cm), followed by Ssth(274.5 cm) and lowest on Ridge(211.5 cm). The diameter growth was greatest on Ssth(7.37 cm), followed by Snth(7.10 cm) and lowest on Ridge(5.72 cm). The volume growth was highest on Ssth(4257.7 cm3), followed by Snth(3750.7 cm3) and lowest on Ridge(2093.7 cm3). Therefore, we should consider and include the concept of slope orientation together with differences in habitat environments in afforestation projects when creating artificial forests with P. densiflora. These study results can serve as important preliminary data for future establishment of artificial forest of P. densiflora in a post-fire plantation. 展开更多
关键词 Pinus densiflora Growth characteristics Contour conditions Planted stand Post-fire plantation
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