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11.
黄安庆 《科技成果管理与研究》2008,(8):39-41
经济型数控车床约占数控机床总量的25％。由于其结构及其经济性,尾座没有自动进给功能,零件需钻孔时,按常规的做法,仍然是和在普通车床上一样在尾座上安装钻头,通过转动尾座手轮进行钻孔。批量生产中,操作者的劳动强度增大,生产效率较低,而且孔的深度尺寸精度也不高。鉴于此,本文特设计了一套能实现经济式数控车床自动钻孔的夹具,以进一步完善经济型数控车床的自动化功能,既保证了产品的质量又较好地捍高了牛产妁率。 相似文献
12.
本文提出了一种在贴片上加载改进的U形缝隙的新型双频微带天线。该天线结构简单,可以应用在无线局域网802.11b（2.4~2.48GHz）和802.11a（5.150~5.350GHz）的系统中,而且只需简单修改天线尺寸参数就可以实现对天线高频段和低频段的调节。本天线使用Ansoft公司的HFSS软件进行仿真和优化,在低频和高频分别获得100MHz和300MHz的带宽,并且能达到实际应用的波束宽度、增益和交叉极化电平。 相似文献
13.
该文介绍在磨削刀具深孔时所采用压板式夹具的加工方法,其磨削效率高,既能提高磨削刀具深孔基准的精度,降低废品率,又可节约辅助工时,延长夹具的使用寿命。 相似文献
14.
The expansion joints are expected to have movement capacity, bearing capacity for static and dynamic loading, water-tightness, low noise emission and traffic safety. In particular, the failure due to impact loading is the main reason for the observed damages. The problem of dynamic behavior of the expansion joints is so complex that we shall focus our attention on the impact factor for vehicle load that is governed by traffic impact. In order to overcome this difficulty, the cantilever-toothed aluminum joint (finger joint) is one of the promising joints under impact loading. In this study, from the viewpoint of design methodology, numerical studies for impact behavior were conducted for aluminum alloy expansion joints with perforated dowels. The design impact factor for the expansion joints with the perforated dowels against traffic impact loading was examined by using numerical simulations. 相似文献
15.
近自然理念构建城市森林 总被引：2，自引：0，他引：2
WANG Li-zhen 《湖北生态工程职业技术学院学报》2007,(1)
随着时代的进步,社会的发展,城市森林必将推动城市的发展。生态优先,就是近自然理念,近自然以其整体观和生态学原理对城市森林规划有着非常重要的指导作用。 相似文献
16.
Ghulam Qasim Mehboob ur Rehman A. Kareem . School of Communication Information Engineering Shanghai University Shanghai China . Gomal University D.I.Kham Pakistan 《上海大学学报(英文版)》2000,4(1):27-30
1 Ｉｎｔｒｏｄｕｃｔｉｏｎ Ａｎｕｍｂｅｒｏｆｆｕｌｌｗａｖｅａｎａｌｙｓｅｓｈａｖｅｂｅｅｎｐｒｏｐｏｓｅｄｉｎｔｈｅｐａｓｔｔｗｏｄｅｃａｄｅｓ[1～3].Ｔｈｅｓｅａｌｌｐｒｅｄｉｃｔｔｈｅｃｈａｒａｃｔｅｒｉｓｔｉｃｓｏｆｍｉｃｒｏｓｔｒｉｐａｎｔｅｎｎａｓｒｉｇｏｒｏｕｓｌｙａｔｈｉｇｈｅｒｆｒｅｑｕｅｎｃｉｅｓ.Ｔｈｅｓｐｅｃｔｒａｌｄｏｍａｉｎｍｅｔｈｏｄｏｆｍｏｍｅｎｔｓ[3],ｕｓｉｎｇｓｉｍｐｌｅｂａｓｉｓｆｕｎｃｔｉｏｎｓｒｅｑｕｉｒｅｓａｌａｒｇｅｓｉｚｅｍａｔｒｉｘｓｕｃｈａｓ(… 相似文献
17.
局部荷载作用下工字形梁腹板的弹性屈曲分析 总被引：1，自引：0，他引：1
钢结构工程中经常遇到一定宽度的均布荷载通过翼缘传递到腹板上的情况，这种荷载称为局部荷载。本文对工字形梁腹板在局部荷载作用下的弹性屈曲进行了有限元分析，得到了不同宽度的荷载作用下工字形梁腹板的弹性屈曲系数，着重考虑了翼缘的转动约束对腹板屈曲的影响。通过数据拟合得到了物理意义明确、精度很高的计算公式。 相似文献
18.
在分析护线盘零件结构特征的基础上,设计了其加工的工艺方案,提出了后续工序加工中防薄壁变形的工艺问题,设计了弹性内胀夹紧以及引线槽侧立铣削加工的简易夹具,并就其设计制作的要点进行了分析说明,有效地保证了实际加工的需要。 相似文献
19.
《Information processing & management》2022,59(4):102950
Human skeleton, as a compact representation of action, has attracted numerous research attentions in recent years. However, skeletal data is too sparse to fully characterize fine-grained human motions, especially for hand/finger motions with subtle local movements. Besides, without containing any information of interacted objects, skeleton is hard to identify human–object interaction actions accurately. Hence, many action recognition approaches that purely rely on skeletal data have met a bottleneck in identifying such kind of actions. In this paper, we propose an Informed Patch Enhanced HyperGraph Convolutional Network that jointly employs human pose skeleton and informed visual patches for multi-modal feature learning. Specifically, we extract five informed visual patches around head, left hand, right hand, left foot and right foot joints as the complementary visual graph vertices. These patches often exhibit many action-related semantic information, like facial expressions, hand gestures, and interacted objects with hands or feet, which can compensate the deficiency of skeletal data. This hybrid scheme can boost the performance while keeping the computation and memory load low since only five extra vertices are appended to the original graph. Evaluation on two widely used large-scale datasets for skeleton-based action recognition demonstrates the effectiveness of the proposed method compared to the state-of-the-art methods. Significant accuracy improvements are reported using X-Sub protocol on NTU RGB+D 120 dataset. 相似文献
20.
Plagiarism continues to be a concern within academic institutions. The current study utilised a randomised control trial of 137 new entry tertiary students to assess the efficacy of a scalable short training session on paraphrasing, patch writing and plagiarism. The results indicate that the training significantly enhanced students' overall knowledge about in-text referencing protocols. Importantly, this knowledge was found to translate into applied skills, with the intervention group performing significantly better in a practical skills application task. Moreover, the findings suggest that it is confidence in writing in English, not language background per se, which plays a significant role in students' practical skills in referencing and their confidence in performing assignment preparation tasks that can help them avoid claims of inadvertent plagiarism. 相似文献