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81.
不同株行距下大豆性状的因子分析 总被引:6,自引:0,他引:6
研究不同株行距配置对大豆农艺性状及产量的影响,为大豆高产栽培提供理论依据。以合丰45、红丰11为试材,设计了9个不同的群体分布进行田间试验,用统计及因子分析法对14个性状分析。结果表明:(1)株行距配置对有效分枝影响最大(其变异系数62%),其次是结荚高度、单株粒数、单株粒重、有效节数、节间长度。(2)单株粒重与单株粒数呈极显著正相关,株高同节间长、有效分枝等性状呈极显著正相关,同有效节数、主茎节数呈极显著的负相关。(3)提取3个公因子:生长性状因子、产量性状因子、含水量因子,累计贡献率93.59%。因子综合得分表明,合丰45的综合得分均高于红丰11在9个行株距配置下。(4)合丰45获得高产的田间最佳株行距配置是:垄上行距12cm×株距14cm。 相似文献
82.
Te-Hsin Yang Song-Yung Wang Cheng-Jung Lin Ming-Jer Tsai Far-Ching Lin 《Journal of Wood Science》2007,53(1):31-39
The purpose of this study was to measure the strain of glulam laminae by affixing a strain gauge at the central axis of the
lateral face in order to determine the effect of the configuration of the glulam. Japanese cedar and southern pine were used
in the study. The strain and stress of the laminae during the bending test were recorded, and the modulus of elasticity (MOE) was calculated. The influence of the MOE of the adhesive layers was also considered. Results showed that the MOE of the laminated elements increased as its specific gravity increased, although the specific gravity was not the only factor
evaluated. The MOE of glulam (E
bsg) measured by the strain gauge method was very close to the observed MOE of glulam (E
b) and a significant linear relationship was identified. The MOE (e) of laminae measured by the strain gauge method was very close to that determined (E) under the “free condition” before bonding. The difference between the modified MOE (E
bsa) and E
bsg was not significant. The MOE of glulams made of heterogeneously graded lumbers were about 23% and 31% larger than the average MOE of their laminae for Japanese cedar and southern pine, respectively. The actual neutral axis was just below the longitudinal
center line. It shifted slightly within the proportional limit range and moved downward when the load increased. 相似文献
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给出了花式喷泉的喷水花样,并选择西门子的PLC作为控制器,分配了4种喷水花样下PLC的I/O接口、设计了PLC的外部接线图及控制梯形图,同时用组态王软件完成了花式喷泉系统人机界面的设计,通过人机界面和西门子PLC之间的通讯,实现了小型喷泉系统的PLC控制。 相似文献
86.
随着人们经济水平和生态文明意识的不断提高,人居环境生态化建设正在成为房地产建设的发展趋势。针对城市林房系统配置内容、配置原则、配置方法和对配置效果优劣的评价进行了比较深入的理论分析,并选择了北京珠江绿洲住区进行了个案研究。 相似文献
87.
简要介绍牡丹园基本情况、历史沿革、功能分区、牡丹及其他绿化植物配置方法等内容,旨在分享栽培牡丹多年的经验。 相似文献
88.
以华盛顿植物园为研究对象,系统论述了形态构成在华盛顿植物园园林植物设计中发挥的作用。运用实例分析了华盛顿植物园中园林植物的形态构成。指出点状植物造型是一切形态的基础,具有积聚性,向心性,并能根据植物大小形成对比;线作为点移动形成的轨迹,线状植物构景也是利用线的粗、细、长、短、方、圆、曲、直之分,形成不同的植物景观;面体状植物构景则将植物按照体块组合,形成对比、点景等造景效果。最后,笔者还举实例分析了点状、线状、面体状盆栽植物栽培容器的搭配之道,为我国园林植物设计提供了详实的借鉴资料。 相似文献
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4-SPS/PPU型并联机构工作空间与尺度分析 总被引:1,自引:0,他引:1
以4-SPS并联机构为研究对象,采用加约束从动支链的构型演变方法得到一类2T2R(两个移动和两个转动)4自由度并联机构。根据速度Jacobian矩阵分析了机构的奇异位形,建立了4-SPxyz S/PxPzUxz 并联机构的工作空间求解的约束条件,得到了机构的位置和姿态工作空间,并提出利用“点集”近似计算位置工作空间大小的方法。引入敏感度概念,利用数值法解得了位置工作空间大小和姿态工作空间范围与机构尺度参数之间的关系,为机构尺度参数的选取提供了依据。 相似文献