The effects of bark on komatsuna (Japanese spinach) and tomato were investigated by changing the nitrogen content of chemical fertilizers and bark mixing ratio. Mixing 25 and 50% of bark with soil improved komatsuna g...The effects of bark on komatsuna (Japanese spinach) and tomato were investigated by changing the nitrogen content of chemical fertilizers and bark mixing ratio. Mixing 25 and 50% of bark with soil improved komatsuna growth, and also exceeded the growth rates obtained by using chemical fertilizers. However, komatsuna could not grow in 100% bark alone, with excessive amounts of bark majorly inhibiting komatsuna growth. The aeration of bark also did not enhance komatsuna growth. The nitrogen content and bark-mixing ratio had a much lower impact on tomato growth compared to komatsuna. In comparison, aerated bark was more effective in enhancing tomato growth compared to komatsuna growth.展开更多
为获得高层建筑围护结构设计风荷载,通常需要考虑其表面风压系数的概率特征,进而进行极值估计。针对当前基于超越阈值模型的风压系数极值估计方法存在阈值选取困难,需要较大样本的不足,基于高层建筑标准模型进行风洞试验,首先研究其表...为获得高层建筑围护结构设计风荷载,通常需要考虑其表面风压系数的概率特征,进而进行极值估计。针对当前基于超越阈值模型的风压系数极值估计方法存在阈值选取困难,需要较大样本的不足,基于高层建筑标准模型进行风洞试验,首先研究其表面风压系数的概率特征,结果表明迎风区测点接近高斯分布,分离区测点风压系数母体接近Gamma分布,风压系数极小值接近GEV(general extreme value,GEV)分布;提出一种改进的POT(peak over threshold,POT)极值估计方法进行表面风压系数极值估计,进而与几种传统极值估计方法进行对比,结果表明改进POT极值估计方法可实现小样本的风压系数极值估计,其估计结果与大样本容量的标准极值偏差小于5%,且稳定性较好;最后给出了标准高层建筑模型表面极值风压系数。展开更多
文摘The effects of bark on komatsuna (Japanese spinach) and tomato were investigated by changing the nitrogen content of chemical fertilizers and bark mixing ratio. Mixing 25 and 50% of bark with soil improved komatsuna growth, and also exceeded the growth rates obtained by using chemical fertilizers. However, komatsuna could not grow in 100% bark alone, with excessive amounts of bark majorly inhibiting komatsuna growth. The aeration of bark also did not enhance komatsuna growth. The nitrogen content and bark-mixing ratio had a much lower impact on tomato growth compared to komatsuna. In comparison, aerated bark was more effective in enhancing tomato growth compared to komatsuna growth.
文摘为获得高层建筑围护结构设计风荷载,通常需要考虑其表面风压系数的概率特征,进而进行极值估计。针对当前基于超越阈值模型的风压系数极值估计方法存在阈值选取困难,需要较大样本的不足,基于高层建筑标准模型进行风洞试验,首先研究其表面风压系数的概率特征,结果表明迎风区测点接近高斯分布,分离区测点风压系数母体接近Gamma分布,风压系数极小值接近GEV(general extreme value,GEV)分布;提出一种改进的POT(peak over threshold,POT)极值估计方法进行表面风压系数极值估计,进而与几种传统极值估计方法进行对比,结果表明改进POT极值估计方法可实现小样本的风压系数极值估计,其估计结果与大样本容量的标准极值偏差小于5%,且稳定性较好;最后给出了标准高层建筑模型表面极值风压系数。
