摘要
电阻抗成像技术(Electrical impedance tomography,EIT)在当今生物医学领域展开了广泛深入的研究,根据其利用材料自身的阻抗特性来表征其内部结构的基本原理,同时研究发现金属材料的疲劳损伤模型与生物组织有诸多相似之处,因此为解决金属材料损伤检测的相关问题,提出一种应用于金属材料疲劳损伤的阻抗法检测技术。根据电阻抗成像、金属材料电特性等相关理论基础,建立了金属材料疲劳损伤的数学物理模型和有限元模型。针对阻抗法成像的正问题、逆问题进行了深入研究,利用有限元仿真方法对边界电位信息进行了提取分析。介绍了基于反投影算法的动态成像技术的实现方法并进行了仿真研究,取得良好的成像效果。对45#钢材料的长方体试样进行了高周疲劳实验,并采用四端法进行微电阻测量,通过多电极模型的测量结果分析,实现了疲劳损伤位置的一维定位检测。
Aiming at the problem that the accuracy and recall rate of knowledge matching algorithm based on vector space model in product design knowledge management system are not high,the characteristics of product design knowledge and the defects of traditional vector space model were studied,and the vector space was reconstructed,then the semantics and semantics structure vector space model was established,on the basis of which a knowledge matching algorithm based on reconstructed vector space model was proposed.Aiming at the algorithm,the feature weight calculation and feature similarity algorithm were studied respectively,and the similarity of text semantic structure was introduced,and the appropriate knowledge is matched for the designer by text similarity calculation.The knowledge management prototype system was developed and the product design knowledge of an environmental protection enterprise was taken as an example to verify that the method has good accuracy rate,recall rate and F1-score.
作者
孙亮
毛汉领
黄振峰
李欣欣
SUN Liang;MAO Han-ling;HUANG Zhen-feng;LI Xin-xin(College of Mechanical Engineering,Guangxi University,Guangxi Nanning530004,China)
出处
《机械设计与制造》
北大核心
2020年第4期177-181,共5页
Machinery Design & Manufacture
基金
国家自然科学基金(51365006)。
关键词
金属材料
疲劳损伤
阻抗法检测
电阻抗成像技术
有限元
Metal Materials
Fatigue Damage
Impedance Detection
Electrical Impedance Tomography
Finite Ele-ment
