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331.
本文基于曲面相交理论,依据辅助圆锥面和辅助平面与已回转面相交的三面共点原理,给出了图解回转体表面上等倾曲线的原理与方法,同时还给出了适合于微机求解等倾曲线上点的坐标的数值计算公式。 相似文献
332.
利用喷射沉积技术成功地制备了Ni-Al-Mo系Ni3Al基高温合金及其复合材料盘坯,对其显微组织和力学性能进行了测试和分析,并对陶瓷粒子的复合机制进行了初步探讨。 相似文献
333.
Experimental study of an aircraft fuel tank inerting system 总被引:3,自引:2,他引:1
In this work, a simulated aircraft fuel tank inerting system has been successfully established based on a model tank. Experiments were conducted to investigate the influences of different operating parameters on the inerting effectiveness of the system, including flow rate of the inert gas(nitrogen-enriched air), inert gas concentration, fuel load of the tank and different inerting approaches. The experimental results show that under the same operating conditions, the time span of a complete inerting process decreased as the flow rate of inert gas was increased; the time span using the inert gas with 5% oxygen concentration was much longer than that using pure nitrogen;when the fuel tank was inerted using the ullage washing approach, the time span increased as the fuel load was decreased; the ullage washing approach showed the best inerting performance when the time span of a complete inerting process was the evaluation criterion, but when the decrease of dissolved oxygen concentration in the fuel was also considered to characterize the inerting effectiveness, the approach of ullage washing and fuel scrubbing at the same time was the most effective. 相似文献
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通过用EDS法分析了静态挂片表面沉积物的元素组成,运用动电位扫描极化曲线和滞后环实验等电化学方法对实验室和现场垢样的SEM和XRD的形貌和组成进行分析,研究了Q235钢在塔1井采出液水相中的腐蚀机理,结果表明塔1井采出液引起腐蚀穿孔的原因是垢下腐蚀而不是点蚀,腐蚀的速度受腐蚀反应的阴极过程控制.用旋转挂片仪筛选出的缓蚀剂用量为50 mg/L时缓蚀率超过90%,WJF-6缓蚀剂起到缓蚀作用的根本原因是抑制了电极反应的阴极过程. 相似文献
336.
Calibration of robotic drilling systems with a moving rail 总被引:2,自引:1,他引:2
Industrial robots are widely used in aircraft assembly systems such as robotic drilling systems. It is necessary to expand a robot's working range with a moving rail. A method for improving the position accuracy of an automated assembly system with an industrial robot mounted on a moving rail is proposed. A multi-station method is used to control the robot in this study. The robot only works at stations which are certain positions defined on the moving rail. The calibration of the robot system is composed by the calibration of the robot and the calibration of the stations.The calibration of the robot is based on error similarity and inverse distance weighted interpolation.The calibration of the stations is based on a magnetic strip and a magnetic sensor. Validation tests were performed in this study, which showed that the accuracy of the robot system gained significant improvement using the proposed method. The absolute position errors were reduced by about 85%to less than 0.3 mm compared with the maximum nearly 2 mm before calibration. 相似文献
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工业微机控制系统小信号采集的抗干扰措施 总被引:1,自引:0,他引:1
本文简述了工业微机控制系统小信号采集过程中常见的干扰来源,并介绍了一种简便,有效的抗干扰措施。 相似文献
340.
The kernel of interval grey number is most likely the real number,which can be used to represent whitenization value of interval grey number.A novel method for calculating kernel of interval grey number is constructed based on the geometric barycenter of whitenization weight function in the two-dimensional coordinate plane,and the calculation of kernel is converted to the calculation of barycenter in geometric figures.The method fully considers the effect of all information contained in whitenization weight function on the calculation result of kernel,and is the extension and perfection of the existing methods in the scope of application. 相似文献