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材种出材率预估模型研究 被引量:11
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作者 谢哲根 唐正良 +2 位作者 翁卫松 戴俊强 王洪喜 《浙江林学院学报》 CSCD 1996年第4期392-396,共5页
推导出一个一致性材种出材率预估模型系统。介绍了单木理论材种出材率计算实现程序,以杉木为例,给出了计算结果。最后对削度方程及材种出材率有关问题作了分析和讨论。
关键词 削度方程 材种 出材率 预估数学模型 材积表
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挤密桩在红黏土地基中挤密效果影响因素试验研究 被引量:4
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作者 赵秀绍 谭周勇 +2 位作者 李凯 郑伟 莫林利 《铁道科学与工程学报》 CAS CSCD 北大核心 2018年第7期1730-1737,共8页
基于室内桩孔水泥土夯击试验,研究夯锤形状、夯锤落距和夯击次数对挤密力和压实系数的影响规律,建立拟合数学模型。研究结果表明:平底锤对桩底的挤密力最大,锥底锤对桩侧的挤密力最大。挤密力和桩体压实系数与夯击次数、夯锤落距之间存... 基于室内桩孔水泥土夯击试验,研究夯锤形状、夯锤落距和夯击次数对挤密力和压实系数的影响规律,建立拟合数学模型。研究结果表明:平底锤对桩底的挤密力最大,锥底锤对桩侧的挤密力最大。挤密力和桩体压实系数与夯击次数、夯锤落距之间存在对数函数相关性,用对数数学模型计算挤密力平均误差不超过7 k Pa,压实系数平均误差不超过2%;根据桩体压实系数的数学模型和挤密力随夯击次数的规律,以夯击能作为考量标准,提出最优夯击方案为锤底为锥形、30 cm落距和每层夯击30次。 展开更多
关键词 水泥土挤密桩 数学预估模型 挤密力 锤底形状 优化
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Dynamic Model for Evaluation of Risk Factors During Work in Hot Environment
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作者 Irena Yermakova Anastasiia Nikolaienko Alia Grigorian 《Journal of Physical Science and Application》 2013年第4期238-243,共6页
Mathematical model is developed for prediction of physiological changes in man during work in hot environment taking into consideration intensity of work, clothing and environment. To evaluate human functional state t... Mathematical model is developed for prediction of physiological changes in man during work in hot environment taking into consideration intensity of work, clothing and environment. To evaluate human functional state the heat stress index was calculated. Modeling researches made the conclusion that the main risk factor during work in hot environment is water losses that happens through thermoregulatory sweat evaporation. Modeling showed that in humid environment man wearing protective clothing has short time to work as water losses became more than 2% of human weight that means body dehydration. Preliminary model prediction can be used as preventive method to avoid hazard of human health. 展开更多
关键词 Thermoregulatory model WORK risk factors hot environment protective clothing.
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