section grading

基本解釋

Timber structures-Strength graded structural timber with rectangular cross section-Part 3: Machine grading;
木結構按強度分類的矩形截面承重木料第3部分：機械分選；
Based on analysis of heavy minerals, paleocurrent and clastic particles grading, the sediment of Yanchang section in Ordos Basin comes from two types of parent rock.
根據重礦物組合、古流向和碎屑顆粒粒度等資料，對鄂爾多斯盆地上三疊統(tǒng)延長組物源區(qū)的母巖性質、物源方向及演變特征等進行了分析。
This research selects factors according to the demand of urban land grading and section otherness in research area and sets up factors system effecting urban-grade between cities;
根據城鎮(zhèn)土地分等的要求和研究區(qū)的地域差異性選擇因素因子，從而建立影響城鎮(zhèn)間土地等的因素因子體系；