期刊文献+
共找到4篇文章
< 1 >
每页显示 20 50 100
散粒体斜坡上滚石法向碰撞恢复系数研究 被引量:3
1
作者 汤明高 赵欢乐 毛宇祥 《防灾减灾工程学报》 CSCD 北大核心 2023年第3期604-613,共10页
国内外在研究滚石碰撞问题时多将碰撞目标假设为弹塑性体,从而推导出恢复系数计算公式。但是对于散粒体斜坡,由于具有结构松散、高压缩、低黏结力等物理力学特性,如果将其完全考虑为弹塑性体,那么低估了其自身的耗能潜力。为此,我们考... 国内外在研究滚石碰撞问题时多将碰撞目标假设为弹塑性体,从而推导出恢复系数计算公式。但是对于散粒体斜坡,由于具有结构松散、高压缩、低黏结力等物理力学特性,如果将其完全考虑为弹塑性体,那么低估了其自身的耗能潜力。为此,我们考虑了松散介质的孔隙压密特征,改进提出了散粒体斜坡上滚石法向碰撞恢复系数的计算式,并探讨了滚石碰撞再回弹的临界条件。同时以西藏昌都察达隧道进口散粒体斜坡为算例进行数值模拟,分析了5种影响因素下滚石法向碰撞恢复系数变化规律,并与改进公式、已有相关公式计算结果进行了对比分析。结果表明改进公式与数值模拟结果较为吻合,优于假设为弹塑性体的公式计算值。研究思路及成果可为类似区域性问题提供参考。 展开更多
关键词 滚石 散粒体斜坡 法向碰撞恢复系数 动能守恒定律 计算公式
在线阅读 下载PDF
一道力学题的分析及启示
2
作者 王杏娣 《浙江海洋学院学报(自然科学版)》 CAS 2001年第2期177-181,共5页
讨论了一力学题的多种解法并分析了如何从解题中获取最大的效率。
关键词 力学题 分析 解法 动量定理 动能守恒定律
在线阅读 下载PDF
Non-invasive glucose measuring apparatus based on conservation of energy method 被引量:1
3
作者 陈真诚 金星亮 +2 位作者 朱健铭 王弟亚 张婷婷 《Journal of Central South University》 SCIE EI CAS 2009年第6期982-986,共5页
A new non-invasive blood glucose measuring apparatus (NBGMA) made up of MSP430F149 SCM (single chip micyoco) was developed,which can measure blood glucose level (BGL) frequently,conveniently and painlessly. The hardwa... A new non-invasive blood glucose measuring apparatus (NBGMA) made up of MSP430F149 SCM (single chip micyoco) was developed,which can measure blood glucose level (BGL) frequently,conveniently and painlessly. The hardware and software of this apparatus were designed,and detecting algorithms based on conservation of energy method (COEM) were presented. According to the law of conservation of energy that the energy derived by human body equals energy consumed by metabolism,and the relationship between convection,evaporation,radiation and the BGL was established. The sensor module was designed. 20 healthy volunteers were involved in the clinical experiment. The BGL measured by an automatic biochemical analyzer (ABA) was set as the reference. Regression analysis was performed to compare the conservation of energy method with the biochemical method,using the 20 data points with blood glucose concentrations ranging from 680 to 1 100 mg/L. Reproducibility was measured for healthy fasting volunteers. The results show that the means of BGL detected by NBGMA and ANA are very close to each other,and the difference of standard deviation (SD) is 24.7 mg/L. The correlative coefficient is 0.807. The coefficient of variation (CV) is 4% at 921.6 mg/L. The resultant regression is evaluated by the Clarke error grid analysis (EGA) and all data points are included in the clinically acceptable regions (region A:100%,region B:0%). Accordingly,it is feasible to measure BGL with COEM. 展开更多
关键词 single chip non-invasive measurement blood glucose conservation of energy method
在线阅读 下载PDF
浅谈“三把力学金钥匙”的解题应用
4
作者 杨海斌 《河南农业》 2011年第4X期28-29,共2页
"力是改变物体运动状态的原因",也就是说,物体的运动状态取决于力的作用效果。在力学中有三组重要定律,分别是牛顿第二定律、动能定理和机械能守恒定律、动量定理和动量守恒定律,俗称"三把力学金钥匙"。从这三组定... "力是改变物体运动状态的原因",也就是说,物体的运动状态取决于力的作用效果。在力学中有三组重要定律,分别是牛顿第二定律、动能定理和机械能守恒定律、动量定理和动量守恒定律,俗称"三把力学金钥匙"。从这三组定律的内在联系入手,对三组定律在解题时的应用进行分析与探讨。 展开更多
关键词 牛顿第二定律 动能定理和机械能守恒定律 动量定理和动量守恒定律 应用
在线阅读 下载PDF
上一页 1 下一页 到第
使用帮助 返回顶部