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31.
轴类零件校直工艺广义预测多步算法研究 总被引:4,自引:0,他引:4
本文基于行程控制的轴类零件校直工艺公式 ,构建了模拟轴类零件校直工艺过程的广义预测控制模型 ,应用广义预测算法 ,实现了对轴类零件弹塑性非线性残余变形的均匀控制 ,实验研究表明 ,该方法能满足精密校直要求 ,并且随着控制步长的增多 ,控制效果显著。 相似文献
32.
本文介绍了一种只用十几个分立元件的电子模块,与大型接触器配合使用,可使接触器节省铜线材料60%~70%,大大减少电磁系统的体积。预置电子模块的参数,可实现交流接触器在起动过程、吸持过程的最佳电流控制,为扩展接触器零部件通用性研制出节能、节材、无噪声等性能优良的小型而容易实施的交流接触器产品提供了依据。 相似文献
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设计特种陶瓷零件结构时,必须考虑成型、干燥、烧成及后加工等工艺过程的要求。本文论述了满足上述要求的陶瓷零件结构设计的基本原则,并通过示例进行了详细说明。 相似文献
36.
As additive manufacturing (AM) evolves to become a common method of producing final parts, further study of this computer integrated technology is necessary. The purpose of this research is to evaluate the potential impact of additive manufacturing improvements on the configuration of spare parts supply chains. This goal has been accomplished through scenario modeling of a real-life spare parts supply chain in the aeronautics industry. The spare parts supply chain of the F-18 Super Hornet fighter jet was selected as the case study because the air-cooling ducts of the environmental control system are produced using AM technology. In total, four scenarios are investigated that vary the supply chain configurations and additive manufacturing machine specifications. The reference scenario is based on the spare parts supplier's current practice and the possible future decentralization of production and likely improvements in AM technology. Total operating cost, including downtime cost, is used to compare the scenarios. We found that using current AM technology, centralized production is clearly the preferable supply chain configuration in the case example. However, distributed spare parts production becomes practical as AM machines become less capital intensive, more autonomous and offer shorter production cycles. This investigation provides guidance for the development of additive manufacturing machines and their possible deployment in spare parts supply chains. This study contributes to the emerging literature on AM deployment in supply chains with a real-world case setting and scenario model illustrating the cost trade-offs and critical requirements for technology development. 相似文献
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Today parametric associative CAD systems must help companies to create more efficient virtual development processes. While dealing with complex parts (e.g. the number of surfaces of the solid) no CAD modeling methodology is existing. Based on the analysis of industrial designers' practices as well as student practices on CAD, we identified key factors that lead to better performance. Our objective in this article is to propose a practical method for complex parts modeling in parametric CAD system. An illustration of the performances and the results obtained by this method are presented comparing the traditional method with the proposed one while using an academic case and then an industrial case. 相似文献
38.
SHI Xin 《计算机辅助绘图.设计与制造(英文版)》2014,(4):7-13
For virtually realizing the graphic realism display of DXF machine parts, in AutoCAD2007 graphic drawing environment, an interactive experimental method was taken to realize the display of graphic in DXF, which was taken as the data-exchanged interface and source. Based on depth analysis of DXF data structure, take one drawing of DXF lathe turning rotational part asthe test piece. By VC++6.0 programming, part's geometry information could be obtained. Through data processing, 3D data of the test piece could be generated, which is based on 2D data of DXF test piece. Then, OpenGL graphic processing technologies (light, material, texture, map, et al.) were applied on the 3D display of test piece from DXF files or program modules. Finally based on the test report, results of the system functions were shared to prove the realization of system design, and the feasibility of algorithms used. In the developed software, Machine Designers could get a full view of machine parts, and do some proper modifications. The study content and results of our work have some theory and practical significance on the application of program design in the practical projects. 相似文献
39.
针对汽车零部件取货具有多频次和时间窗限制的特点,利用先进的循环取货方式对零部件进行取货.并构建数学模型优化取货路径,利用C-W算法,获得符合所有约束条件的满意解.使其在配送总量一定的情况下,运输总里程大大降低,从而节约了运输成本.最后给出一个算例. 相似文献
40.
根据被积函数的特征分四种情形分别进行讨论,给出了不需转换积分区域D类型交换积分次序而使用分部积分法计算二次积分的方法,首次将分部积分法成功地引入到二重积分的计算中。 相似文献