The J-integral as a controlling parameter was applied to the crack growing process in an elastic-plastic state by Hutchinson and Paris[1], and Shih et. al[2]. An engineering approach based on J-integral was proposed b...The J-integral as a controlling parameter was applied to the crack growing process in an elastic-plastic state by Hutchinson and Paris[1], and Shih et. al[2]. An engineering approach based on J-integral was proposed by Ref.[3]. Obviously, it is necessary to determine whether J is really a bask controlling parameter. It has been shown from the results given in this paper that it is not bask, but the Jn-integral defined in this paper is a proper controlling parameter for crack growth in an clastic-plastic state.展开更多
Since 1980s,with the further reform of political and economic systems,the urban construc-tion in our country has undergone great changes,greater than ever.Such changes pose a series ofnew problems to urban planning:Ho...Since 1980s,with the further reform of political and economic systems,the urban construc-tion in our country has undergone great changes,greater than ever.Such changes pose a series ofnew problems to urban planning:How should planning be suitable for the development of moderncities?How should planning management coordinate with urban planning?How to carry out ur-ban planning under new situations? etc.The answers to these problems lie in one point:urbanplanning and plann ing management must be restructured.Only when the former is well com-bined with the latter can the above problems be solved satisfactorily.This article provides someviews in this respect.展开更多
文摘The J-integral as a controlling parameter was applied to the crack growing process in an elastic-plastic state by Hutchinson and Paris[1], and Shih et. al[2]. An engineering approach based on J-integral was proposed by Ref.[3]. Obviously, it is necessary to determine whether J is really a bask controlling parameter. It has been shown from the results given in this paper that it is not bask, but the Jn-integral defined in this paper is a proper controlling parameter for crack growth in an clastic-plastic state.
文摘Since 1980s,with the further reform of political and economic systems,the urban construc-tion in our country has undergone great changes,greater than ever.Such changes pose a series ofnew problems to urban planning:How should planning be suitable for the development of moderncities?How should planning management coordinate with urban planning?How to carry out ur-ban planning under new situations? etc.The answers to these problems lie in one point:urbanplanning and plann ing management must be restructured.Only when the former is well com-bined with the latter can the above problems be solved satisfactorily.This article provides someviews in this respect.
