The present paper addresses the subject of truss damage identification using measured frequency response functions (FRF). Damage identification matrix is formed using measured FRFs obtained from truss dynamic test. Th...The present paper addresses the subject of truss damage identification using measured frequency response functions (FRF). Damage identification matrix is formed using measured FRFs obtained from truss dynamic test. Then using principal component analysis (PCA),the variable space dimensions of damage identification matrix can be reduced,and original data characters of FRFs can be analyzed and extracted from lower dimension variable space. Thus truss damages can be identified using the multivariate control chart of first several order principal components which contain almost all of original data information. Without the need for modal parameters,the method avoids the errors of modal fitting. In order to validate the reliability of the method,a whole size truss was tested with six types of damage case concerning single or two element damages. The experimental result shows that the proposed method is straightforward and reliable for truss damage identification. Especially,the method has good applicability for the truss under noisy environment and non-linear cases.展开更多
为了使各种编程语言都可以编写符合OLE DB标准的应用程序,微软在OLE DB AP I之上,提供了一种面向对象、与语言无关的应用程序接口,这就是ADO(A ctiveX D ata O b jects)控件。本文介绍利用V isua l B as ic中ADO(A ctiveXD ata O b jec...为了使各种编程语言都可以编写符合OLE DB标准的应用程序,微软在OLE DB AP I之上,提供了一种面向对象、与语言无关的应用程序接口,这就是ADO(A ctiveX D ata O b jects)控件。本文介绍利用V isua l B as ic中ADO(A ctiveXD ata O b jects)与Chart控件结合将数据库的数据信息动态生成图表的方法,他有效地解决了将数据转化为直观图表这一在实际中经常遇到的问题。展开更多
基金the Foundation of Henan Province Key Technology R and D Program(Grant No.0423033700).
文摘The present paper addresses the subject of truss damage identification using measured frequency response functions (FRF). Damage identification matrix is formed using measured FRFs obtained from truss dynamic test. Then using principal component analysis (PCA),the variable space dimensions of damage identification matrix can be reduced,and original data characters of FRFs can be analyzed and extracted from lower dimension variable space. Thus truss damages can be identified using the multivariate control chart of first several order principal components which contain almost all of original data information. Without the need for modal parameters,the method avoids the errors of modal fitting. In order to validate the reliability of the method,a whole size truss was tested with six types of damage case concerning single or two element damages. The experimental result shows that the proposed method is straightforward and reliable for truss damage identification. Especially,the method has good applicability for the truss under noisy environment and non-linear cases.
文摘为了使各种编程语言都可以编写符合OLE DB标准的应用程序,微软在OLE DB AP I之上,提供了一种面向对象、与语言无关的应用程序接口,这就是ADO(A ctiveX D ata O b jects)控件。本文介绍利用V isua l B as ic中ADO(A ctiveXD ata O b jects)与Chart控件结合将数据库的数据信息动态生成图表的方法,他有效地解决了将数据转化为直观图表这一在实际中经常遇到的问题。
