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31.
NIU Jitai GUO Wei ZHANG Xinmei and LIU Xingqiu) State Key Laboratory of Advanced Welding Production Technology Harbin Institute of Technology Harbin China) State Key Laboratory of Metal Matrix Composite Shanghai Jiao Tong University Shanghai China 《稀有金属(英文版)》2003,22(4)
Through the vacuum diffusion welding SiCp/ZL101 aluminum with Cu interlayer,the effect of welding parame-ter and the thickness of Cu on the welded joint property was investigated,and the optimal welding parameters were putforward at the same time.The microstructure of joint was analyzed by means of optical-microscope,scanning electron mi-croscope in order to study the relationship between the macro-properties of joint and the microstructure.The results showthat diffusion welding with Cu interlayer could be used for welding aluminum matrix composites SiCp/ZL101 successfully. 相似文献
32.
介绍2种单片机焊接控制器的功能参数及设计思路。一种采用80C196KB PSD311的16位总线结构;另一种采用89C52的8位总线结构。实践证明单片机系统是焊接设备中比较理想的控制器件。 相似文献
33.
阐述了200MW汽轮机焊接隔板变形这一在国内电站中多次出现的问题,以及由于隔板变形而对机组带来的危害.强调了在隔板发生严重变形时对隔板进行焊接加固的必要性,概述了隔板检查方法,包括隔板表面缺陷、内部缺陷、通流间隙、挠曲变形等的检查,以及隔板加固的工艺要点. 相似文献
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Ioannis Marras Georgios Tzimiropoulos Stefanos Zafeiriou Maja Pantic 《Image and vision computing》2014
We introduce a robust framework for learning and fusing of orientation appearance models based on both texture and depth information for rigid object tracking. Our framework fuses data obtained from a standard visual camera and dense depth maps obtained by low-cost consumer depth cameras such as the Kinect. To combine these two completely different modalities, we propose to use features that do not depend on the data representation: angles. More specifically, our framework combines image gradient orientations as extracted from intensity images with the directions of surface normals computed from dense depth fields. We propose to capture the correlations between the obtained orientation appearance models using a fusion approach motivated by the original Active Appearance Models (AAMs). To incorporate these features in a learning framework, we use a robust kernel based on the Euler representation of angles which does not require off-line training, and can be efficiently implemented online. The robustness of learning from orientation appearance models is presented both theoretically and experimentally in this work. This kernel enables us to cope with gross measurement errors, missing data as well as other typical problems such as illumination changes and occlusions. By combining the proposed models with a particle filter, the proposed framework was used for performing 2D plus 3D rigid object tracking, achieving robust performance in very difficult tracking scenarios including extreme pose variations. 相似文献
36.
王建勋 《自动化与仪器仪表》2014,(6):18-19
本文针对硅弧焊整流器的控制性能,在分析铁磁材料特性的基础上,分别对单铁芯磁放大器和双铁芯磁放大器的结构和工作原理进行了深入的研究,提出了单铁芯磁放大器所存在的缺点以及双铁芯磁放大器的优点,使得硅弧焊整流器的设计采用双铁芯磁放大器,能够避免焊接时焊接电流波形的畸变,对提高焊接质量是有利的。 相似文献
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Traditionally, emotion recognition is performed in response to stimuli that engage either one (vision: image or hearing: audio) or two (vision and hearing: video) human senses. An immersive environment can be generated by engaging more than two human senses while interacting with multimedia content and is known as MULtiple SEnsorial media (mulsemedia). This study aims to create a new dataset of multimodal physiological signals to recognize emotions in response to such content. To this end, four multimedia clips are selected and synchronized with fan, heater, olfaction dispenser, and haptic vest to augment cold air, hot air, olfaction, and haptic effects respectively. Furthermore, physiological responses including electroencephalography (EEG), galvanic skin response (GSR), and photoplethysmography (PPG) are observed to analyze human emotional responses while experiencing mulsemedia content. A t-test applied using arousal and valence scores show that engaging more than two human senses evokes significantly different emotions. Statistical tests on EEG, GSR, and PPG responses also show a significant difference between multimedia and mulsemedia content. Classification accuracy of 85.18% and 76.54% is achieved for valence and arousal, respectively, using K-nearest neighbor classifier and feature-level fusion strategy. 相似文献
39.
Butt joints between Mg alloy AZ31 B and pure Al 1 060 sheets were produced via metal inert gas welding process with Zn-Cd alloy foil. Crack-free Al/Mg butt joints between AZ31 B Mg alloy and pure Al 1060 sheets were obtained. Intermetallic compound layer 1 and layer 2 had formed in fusion zone/Mg alloy and the average thickness of the layer 1 was about 50 μm. The intermetallic compound layer 1 consisted of Al12Mg17 and Mg2Si phases while layer 2 consisted of Al12Mg17, Mg2Si and Mg Zn2 phases. The crack started from the IMC layer at the bottom of the joint and propagated along the brittle IMC layer, then expanded into weld metal during the SEM in situ tensile test. The highest tensile strength of the dissimilar metal butt joints could reach 46.8 MPa and the effect ofinterfacial IMC layer on mechanical property of the joint was discussed in detail in the present study. 相似文献
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