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浏览/检索结果: 共6条，第1-6条 帮助 已选(0)清除 条数/页：5101520253035404550556065707580859095100   排序方式：请选择作者升序作者降序题名升序题名降序发表日期升序发表日期降序提交时间升序提交时间降序 Effects of long-term loading on fire-damaged reinforced-concrete stub columns 期刊论文 MAGAZINE OF CONCRETE RESEARCH, 2019, 卷号: Vol.71 No.9, 页码: 476-487 作者:  Huo, JS;  Liu, HQ;  Xu, X 收藏  |  浏览/下载：6/0  |  提交时间：2019/12/17 compressive strength  temperature-related & thermal effects  testing, apparatus & methods   Effects of long-term loading on fire-damaged reinforced-concrete stub columns. 期刊论文 Magazine of Concrete Research, 2019, 卷号: Vol.71 No.9, 页码: 476-487 作者:  Huo, JS;  Liu, HQ;  Xu, X 收藏  |  浏览/下载：10/0  |  提交时间：2019/12/17 compressive strength  temperature-related & thermal effects  testing, apparatus & methods   Research on multidimensional loading device of material mechanical test 会议论文 MATEC Web of Conferences 作者:  Zhao, G.;  Wang, D.;  Liu, L.;  Fan, R.;  Mi, R. 收藏  |  浏览/下载：9/0  |  提交时间：2019/12/30 Inverse kinematics  Manufacture  Materials testing apparatus  Tensile testing  Determination methods  Loading devices  Mechanism-parameters  Parallel mechanisms  Quasi-static  Stewart platforms  Tensile testing machines  Ultimate strength  Mechanisms   Protection methods for electronic current transformer during extreme circumstance 期刊论文 2010, 2010 Wang Peng; Zhang Gui-xin; Li Lian-zi; Zhu Xiao-mei; Luo Cheng-mu 收藏  |  浏览/下载：5/0 Design and tolerance analysis of compensator for high order aspheric surface testing (EI CONFERENCE) 会议论文 2009 International Conference on Optical Instruments and Technology - Optoelectronic Measurement Technology and Systems, October 19, 2009 - October 22, 2009, Shanghai, China Chen X.; Liu W.; Kang Y.; Wei Z. 收藏  |  浏览/下载：18/0  |  提交时间：2013/03/25 High accuracy is required in surface testing of 90nm nodal point lithography projecting lens. By comparing various aspheric surface testing methods  the structure layout of the compensator is a meniscus positive lens combined with a Plano-convex positive lens. The design results indicate that: primary and high order aberrations are balanced well  we adopt Offner null compensator to test the aspheric surface in the point diffraction interferometer at last. In this paper  MTF exceeds diffraction limit  an Offner compensator is presented on the base of the third order aberration theory to test concave aspheric surface  root-mean-square (RMS) of wave front error /167. The F-number of the system can achieve F/1.64. By the analysis of the process of aspheric surface testing with the designed system  the optical construction parameters of which is determined by introducing equal-quantities spherical aberration to compensate all orders of aspheric coefficients. The field of view of the system is 0.02  a loosen distribution of the tolerance was presented based on the accuracy of measuring apparatus. 2009 SPIE.   Mid-frequency surface error test with a Foucault apparatus (EI CONFERENCE) 会议论文 3rd International Symposium on Advanced Optical Manufacturing and Testing Technologies: Optical Test and Measurement Technology and Equipment, July 8, 2007 - July 12, 2007, Chengdu, China Xuan B.; Li J.; Song S.; Xie J. 收藏  |  浏览/下载：14/0  |  提交时间：2013/03/25 Testing of mid-frequency surface error is of the first importance for fast optics  especially for large aperture aspherics. Foucault test plays a dominant role for surface error inspection before the digital interferometer age  but it seems to have faded out these days because no quantitative results turn out. However  an interferometer with high resolution CCDs is either unavailable or unaccessible in the process of manufacture. As its advantages are realized and recognized for the second time  Foucault test is going back to the stage again. A new theory of calculating the contrast of the shadow pattern of Foucault test is put forward in this paper and some modifications are discussed upon the analyses of the limitation of traditional Foucault apparatus. A paraboloidal mirror was fabricated and tested by the modified Foucault apparatus whose effect has been proved to be great. The methods of controlling mid-frequency error are described in the other paper at this conference- "Multi-mode combine manufacturing technology for large aperture aspheric mirrors"1.