排序方式: 共有86条查询结果,搜索用时 15 毫秒
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本文利用地理信息系统(CIS)对测绘地形、地籍以及生成土地证、房产证等一些图件进行说明,并作相应的转换处理,满足了地籍管理工作的需要.利用这项新技术在地形和地籍测量屯的应用情况做一介绍. 相似文献
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通过对转子表面圆度误差的机理分析,建立了圆度误差的数学模型,并实验验证了数学模型的正确性。分析讨论了圆度误差对采用PID控制策略的电磁轴承系统的控制精度的影响。研究结果表明:圆度误差会使转子作周期振动,当圆度误差信号的频率等于系统固有频率时,振动幅值较大,在这个频率后随频率的增加振动幅值减小。 相似文献
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The instantaneous angle of attack on the blade has a significant effect on the hydrodynamic performance of a vertical-axis tidal-current turbine with straight blades. This paper investigates the influence of different preset angles of attack on the hydro-dynamic performance of a three-bladed, vertical-axis, tidal-current turbine both experimentally and numerically. Experiments are carried out in a towing tank. This tested turbine’s solidity is 0.1146. The preset angles of attack on the blade are -3°, 0° , 3° , and 5°, in the experiments. Experimental results show that with the increase of the preset angle of attack from -3°, to 5° , the hydrodynamic performance of the turbine is improved significantly with the power coefficients being increased from 15.3% to 34.8%, respectively. Compared to the result of a 0° preset angle of attack, the performance of the turbine with positive preset angles of attack is experimentally demonstrated to be beneficial. This performance improvement is also shown by numerical 相似文献
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按照“全程控制”观念,煤矿安全管理的整个过程应该分为“学习、查找工作不足、制定整改措施、验证措施的有效性”四个步骤。1学习做好煤矿安全工作重要的就是要认真学习党的安全生产方针,国家法律法规,以及上级部门对煤矿安全生产的指示精 相似文献
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正印刷企业时常面临印刷机色彩稳定性问题,尤其是使用数字印刷机的印刷企业常常会遇到这样的困境:一旦设备的色彩偏离了预定值,操作人员都不知道如何调整回来。那么,如何找到一种有效的色彩管理方法,让多台数字印刷机之间的色彩保持一致,与此同时,其还能与印刷企业既有的印刷效果相匹配呢?本文将通过 相似文献
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