期刊文献+
共找到4篇文章
< 1 >
每页显示 20 50 100
Intelligent prediction model of tunnelling-induced building deformation based on genetic programming and its application
1
作者 XU Jing-min WANG Chen-cheng +3 位作者 CHENG Zhi-liang XU Tao ZHANG Ding-wen LI Zi-li 《Journal of Central South University》 CSCD 2024年第11期3885-3899,共15页
This paper aims to explore the ability of genetic programming(GP)to achieve the intelligent prediction of tunnelling-induced building deformation considering the multifactor impact.A total of 1099 groups of data obtai... This paper aims to explore the ability of genetic programming(GP)to achieve the intelligent prediction of tunnelling-induced building deformation considering the multifactor impact.A total of 1099 groups of data obtained from 22 geotechnical centrifuge tests are used for model development and analysis using GP.Tunnel volume loss,building eccentricity,soil density,building transverse width,building shear stiffness and building load are selected as the inputs,and shear distortion is selected as the output.Results suggest that the proposed intelligent prediction model is capable of providing a reasonable and accurate prediction of framed building shear distortion due to tunnel construction with realistic conditions,highlighting the important roles of shear stiffness of framed buildings and the pressure beneath the foundation on structural deformation.It has been proven that the proposed model is efficient and feasible to analyze relevant engineering problems by parametric analysis and comparative analysis.The findings demonstrate the great potential of GP approaches in predicting building distortion caused by tunnelling.The proposed equation can be used for the quick and intelligent prediction of tunnelling induced building deformation,providing valuable guidance for the practical design and risk assessment of urban tunnel construction projects. 展开更多
关键词 building deformation genetic programming tunnel construction modification factor
下载PDF
Hot deformation behavior and microstructure evolution of 1460 Al-Li alloy 被引量:2
2
作者 向胜 刘丹阳 +3 位作者 朱瑞华 李劲风 陈永来 张绪虎 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2015年第12期3855-3864,共10页
The hot deformation behavior and microstructure evolution of 1460 Al-Li alloy were investigated by isothermal compression test conducted at various strain rates(10-3-10 s-1) and temperatures(573-773 K). The flow s... The hot deformation behavior and microstructure evolution of 1460 Al-Li alloy were investigated by isothermal compression test conducted at various strain rates(10-3-10 s-1) and temperatures(573-773 K). The flow stress curves were corrected by considering the friction at the platen/specimen interface and the temperature change due to the deformation heating. The effects of strain, strain rate and temperature on the deformation behavior were characterized by the Zener-Hollomon parameter in a hyperbolic-sine equation, and the constitutive equations were established according to the peak flow stress associated with dynamic recovery, dynamic recrystallization and the dissolution of T1 phases. In the entire strain rate and temperature range, the prediction capabilities of the developed constitutive equation are proved to be feasible and effective with a linear correlation coefficient and an average absolute relative error coefficient of 0.9909 and 6.72%, respectively. 展开更多
关键词 1460 Al-Li alloy friction correction temperature rise correction constitutive equation hot deformation behavior
下载PDF
具有庞加莱子群形变群对称性时空中的场论构造
3
作者 张磊 吴奕暐 +2 位作者 杨礼想 魏文叶 薛迅 《科学通报》 EI CAS CSCD 北大核心 2015年第34期3322-3331,共10页
当今物理实验对局域Lorentz和CPT对称性的破缺程度给出了严格的限制,但同时有诸多细微现象都似乎表示这两者可能是破缺的.找到这种可能的破缺并给出匹配的合理的物理图景,将是一件很有意义的事情.由于对所有洛伦兹子群与时空平移群的半... 当今物理实验对局域Lorentz和CPT对称性的破缺程度给出了严格的限制,但同时有诸多细微现象都似乎表示这两者可能是破缺的.找到这种可能的破缺并给出匹配的合理的物理图景,将是一件很有意义的事情.由于对所有洛伦兹子群与时空平移群的半直积群进行形变所可能得到的形变群其相应的时空几何实现基本都是Finsler类型的,在本文中研究了这些时空几何中的质点动力学,得到了其色散关系,并据此研究了这些Finsler时空所容许的场论模型,讨论了标量场、旋量场、矢量场和规范耦合的动力学和相对闵氏时空中场论由形变引起的修正.本文选择研究的Finsler结构,具有明显的时空方向依赖性的.因而,如果时空是Finsler的,那么可以通过某些精心设计的实验观测到这种方向依赖性. 展开更多
关键词 非常狭义相对论 形变 FINSLER几何 Minkowski流形 形变修正
原文传递
高分辨宽能段软X射线光束线热负载影响与修正 被引量:1
4
作者 石应波 王勇 +1 位作者 邰仁忠 丁洪 《激光与光电子学进展》 CSCD 北大核心 2014年第7期194-200,共7页
正在建设中的上海光源梦之线(Dreamline)是一条宽能段、超高能量分辨率的软X射线光束线。如此高指标的光束线在建设过程中有许多难点需要克服,其中光学元件的热变形是达到数万分辨能力的主要障碍。梦之线采用的5 m长的波荡器会产生很高... 正在建设中的上海光源梦之线(Dreamline)是一条宽能段、超高能量分辨率的软X射线光束线。如此高指标的光束线在建设过程中有许多难点需要克服,其中光学元件的热变形是达到数万分辨能力的主要障碍。梦之线采用的5 m长的波荡器会产生很高的热辐射从而使各光学元件,特别是第一块平面镜(M1)和第二块平面镜(M2)发生热形变进而影响整个光束线的性能。因此本文计算了Dreamline各光学元件的热功率密度分布,在此基础上对各光学元件进行了稳态热分析,得到M1、M2达到热平衡时的温度,热变形和面形误差分布,进而利用热变形结果对光束线进行了追迹,并且设计了一套热修正装置指导单色仪自身的聚集调节从而消除镜面热变形对光束线性能的影响。结果表明,即使在镜面热变形最高的情况下,通过对各光学元件进行有效的冷却并通过单色仪自身的聚集调节能消除镜面热形变对光束线性能的影响。 展开更多
关键词 X射线光学 形变修正 面形误差 有限元分析 光束线追迹
原文传递
上一页 1 下一页 到第
使用帮助 返回顶部