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浏览/检索结果: 共3条，第1-3条 帮助 限定条件 内容类型：会议论文     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 Active Countermeasure Mechanism to Waste Dump Based on Spatial Effect 会议论文 Dalian, PEOPLES R CHINA, MAR 30-31, 2013 作者:  Teng, Xiaoyan;  Wang, Haibin 收藏  |  浏览/下载：14/0  |  提交时间：2018/06/05 Waste dump  Treatment on geological disaster  Spatial Effect  Active Countermeasure Mechanism   Study on the azimuth bearing scheme of a large Alt-azimuth telescope (EI CONFERENCE) 会议论文 5th International Symposium on Advanced Optical Manufacturing and Testing Technologies: Large Mirrors and Telescopes, April 26, 2010 - April 29, 2010, Dalian, China Wang H.; Zhang J.; Dai S. 收藏  |  浏览/下载：30/0  |  提交时间：2013/03/25 The azimuth bearing schemes in typical large Alt-azimuth telescopes  especially the 3.5-m APO telescope and the 4.1-m SOAR telescope were analyzed. A scheme of high-angular contacted thrust ball bearing integrated with a radial ball bearing was put forward. According to the Hertz contact theory  the corresponding parameters were designed for engineering application. The static performance parameters  within the range of 60 85 original contact angle were calculated. Compared with the traditional plane thrust ball bearing  the results shows that the high-angular (80) contact thrust ball bearing has more benefits at bearing strength and rigidity for large telescope. The 1500mm diameter prototyping bearing shows good performance  including the axial jitter is 0.009mm  the radial jitter is 0.006mm  the maximum starting torque without load is 30N·m  and the load capacity is more than 30t  which offers advanced technique path for the buildup of the high precision azimuth shafting and the whole telescope system. 2010 Copyright SPIE - The International Society for Optical Engineering.   The effect of service delivery quality on customer value of e-learning systems 会议论文 2012 作者:  Soar,Jeffrey;  Alsabawy,AhmedYounis;  Cater-Steel,Aileen 收藏  |  浏览/下载：2/0  |  提交时间：2020/01/04 Electronic  learning  Educational  institutions  Privacy  Availability  Information  systems  Instruments  customer  value  e-learning  systems  service  delivery  quality