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	Structure buckling load interval analysis of supercavitating projectile (EI CONFERENCE) 会议论文 OAI收割 2011 9th International Conference on Reliability, Maintainability and Safety: Safety First, Reliability Primary, ICRMS'2011, June 12, 2011 - June 15, 2011, Guiyang, China 作者: Zhou L. 收藏 \| 浏览/下载：26/0 \| 提交时间：2013/03/25 As a result of supercavitating projectiles with high underwater velocity their structures undergo high longitudinal force. It is necessary to perform structure buckling load interval analysis because the uncertainty of structural own parameters should be considered. Critical buckling load of supercavitating projectiles is calculated by Galerkin method. The partial matrixes of critical buckling load implicit function to each uncertainty variable are deduced and the interval of structure critical buckling load is calculated by interval analysis and convex model methods. Numerical results show that the nominal value lower and upper bounds of critical buckling load increase with the increment of the ratio of base diameter to cavitator diameter. And the uncertainty degree of basic variables should be controlled as far as possible in the project for high reliability. 2011 IEEE.
	Structure buckling reliability analysis of supercavitating projectile (EI CONFERENCE) 会议论文 OAI收割 2nd Annual Conference on Electrical and Control Engineering, ICECE 2011, September 16, 2011 - September 18, 2011, Yichang, China 作者: Zhou L. 收藏 \| 浏览/下载：13/0 \| 提交时间：2013/03/25 Because the underwater velocity of supercavitating projectile is very high its structure undergo high longitudinal force. It is necessary to perform structure buckling reliability analysis because the randomicity of structural own parameters and flow parameters should be considered. Critical buckling load of supercavitating projectile is calculated by Galerkin method. The partial matrixes of critical buckling load implicit function to each random variable are deduced and structural buckling reliability index is calculated by limit step length iteration method. Numerical results show that the critical buckling load and structural buckling reliability index increase with the increase of the ratio of base diameter to cavitator diameter. And structural buckling reliability index increase with the decrease of velocity coefficient. 2011 IEEE.
	Gimbal displacement error analysis on an electro-optical seeker (EI CONFERENCE) 会议论文 OAI收割 Optical Design and Testing IV, October 18, 2010 - October 20, 2010, Beijing, China 作者: Zhang X.; Zhang X.; Zhang X. 收藏 \| 浏览/下载：34/0 \| 提交时间：2013/03/25 It is essential to analyze the gimbal displacement errors for a seeker due to the importance for cueing of targets and tracking for the final approach. Otherwise for a seeker electro-driven with a concentric glass dome the large errors will decrease the picking pointing and tracking precision rooted from the displacement errors existing between the rotation center of the optical system and the gimbal. And the gimbaled camera system displacement errors are never eliminated but reduced due to the geometric errors consists of geometric tolerances of gimbal structure manufacture installation and vibration coming from working environment. In this paper the gimbal displacement errors in an electro-optically stabilized platform resulting from geometric errors and environment errors were analyzed and shown in detail. The mathematical modal of the gimbal displacement errors created based on multi-body dynamics demonstrated the connection between the gimbal displacement errors and the stabilized platform. Taking a visible light image seeker as a case the diameter is 120mm and the geometric tolerances came from the values of primary design and the vibration data came from the environmental vibration test on the pitch-yaw seeker and at the same time the errors resulting from installation were considered too. Based on calculating the maximum gimbal displacement error will reach to 0.2mm for pitching angle smaller than 40 and yawing angle smaller than 60. However the critical parts have been found out according to the probability theory and the reliability analysis successfully used in the paper and finally the maximum gimbal displacement error reduced to 0.1mm which is acceptable corresponding to the picking pointing and tracking precision for an optical imaging seeker. 2010 Copyright SPIE - The International Society for Optical Engineering.
	Ti (Zr)-Cu-Ni Bulk Metallic Glasses with Optimal Glass-Forming Ability and Their Compressive Properties 期刊论文 OAI收割 Metallurgical and Materials Transactions a-Physical Metallurgy and Materials Science, 2008, 卷号: 39A, 期号: 12, 页码: 2990-2997 Y. L. Wang; J. Xu 收藏 \| 浏览/下载：24/0 \| 提交时间：2012/04/13 supercooled liquid region mg-cu-y mechanical-properties amorphous-alloys critical diameter ni plasticity ductility strength sn
	Recent progress on asphere manufacturing and testing at CIOM (EI CONFERENCE) 会议论文 OAI收割 Advanced Optical Manufacturing and Testing Technology 2000, November 1, 2000 - November 3, 2000, Chengdu, China 作者: Zhang X.; Yu J.; Zhang X.; Zhang X. 收藏 \| 浏览/下载：22/0 \| 提交时间：2013/03/25 The manufacturing procedure of a 500 mm in diameter f/2 hyperbolic primary mirror based on Computer-Controlled Polishing is introduced in detail. The mirror was finally polished to the shape accuracy of 13 nm rms and the surface roughness of 2 nm Ra. Testing methods and data analysis for different stages ranging from grinding to polishing are discussed. Some critical factors affecting the efficiency and accuracy of the grinding/polishing procedure are summarized. In addition the preliminary work to make large off-axis asphere mirrors is presented. The difficulties in polishing and testing for both circular aperture and rectangular aperture mirrors are previewed and a possible solution is given. To control the geometrical parameters such as radius of curvature and conic constant a new profiler has been built and it has proven very useful to improve the grinding efficiency. Finally the manufacturing of small aspheres using deterministic grinding tool is also introduced. The fine grinding procedure of LOH's asphere grinding machine is presented.