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Determination of La/CeO_2 content in ilmenite electrode coating

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Rare Metals 2015年第7期34卷 505-509页

作者： Yong-Huan Guo Xi-Ying Fan Liang Zhang Hui Fan Yi-Jun Xu College of Mechanical and Electrical Engineering Jiangsu Normal University Xuzhou Hongyuan automation Technology limited company

The ilmenite welding electrode has advantages of low cost and excellent welding technological ***, the welding quality is affected adversely by its poor crack *** solve this problem, 12 kinds of rare earths coating formulas were optimized by means of orthogonal test design and curve *** the powders containing La/Ce O2 were extruded into ilmenite welding electrode through screw-type pressing–scribbling *** that, a series of mechanical properties tests were conducted according to national ***, the mechanical properties data were analyzed comprehensively by analyzing variance, boxplot as well as Minitab 3D surface *** results show that compared with the formula without rare earth, the deposited metal’s impact toughness,the lower yield strength, the tensile strength, and the hardness are increased by 54.44 %, 9.25 %, 6.37 %, and4.27 %, *** other words, Electrode 6 with the La/Ce O2 amount of 0.5 %/0.1 % in coating has better mechanical properties.

关键词： Ilmenite-type electrode Lanthanum/cerium oxide Var

High-efficiency ultrasonic assisted drilling of CFRP/Ti stacks under non-separation type and dry conditions

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2024年第4期25卷 275-291页

作者： Enze YING Zehua ZHOU Daxi GENG Zhenyu SHAO Zhefei SUN Yihang LIU Lianxing LIU Xinggang JIANG Deyuan ZHANG School of Mechanical Engineering and automation Beihang UniversityBeijing 100191China Beijing Chenjing Electronics company limited Beijing 100015China Aerospace Times Feihong Technology company limited Beijing 100094China

In this study,to address the low efficiency for conventional ultrasonic-assisted drlling(UAD)of carbon fiber-reinforced plastic and titanium alloy(CFRP/Ti)stacks,feasibility experiments of non-separation UAD,in which continuous cutting between the tool and the workpiece occurs at a high feed rate,are carried *** experimental results indicate that,compared to conventional separation UAD,the non-separation UAD effectively reduces the cutting forces by 24.2%and 1.9%for CFRP stage and 22.1%and 2.6%for the Ti stage at the feed rates of 50 and 70μm/r,***,the non-separation UAD significantly improves hole quality,including higher hole diameter accuracy,lower hole surface roughness,and less hole *** addition,the non-separation UAD can decrease adhesive tool *** study demonstrates that,compared to conventional drilling(CD),the non-separation UAD can effectively improve drilling quality and tool life while maintaining high efficiency.

关键词： Carbon fiber-reinforced plastic and titanium alloy(CFRP/Ti)stacks Ultrasonic-assisted drlling(UAD) Cutting force Surface integrity Tool wear

Motion estimation of elastic articulated objects from image contours

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Journal of Harbin Institute of Technology(New Series) 2008年第3期15卷 326-330页

作者：潘海朗戴跃伟石磊 College of automation Nanjing University of Science & Technology Shanghai Berkeley Biology and Technology limited company

A new method of elastic articulated objects (human bodies) modeling was presented based on a new conic curve. The model includes 3D object deformable curves which can represent the deformation of human occluding contours. The deformation of human occluding contour can be represented by adjusting only four deformation parameters for each limb. Then, the 3D deformation parameters are determined by corresponding 2D contours from a sequence of stereo images. The algorithm presented in this paper includes deformable conic curve parameters determination and the plane, 3D conic curve lying on, parameter determination.

关键词： elastic articulated object, human body modeling motion estimation

Unsupervised FIR adaptive filtering and its frequency domain analysis

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Journal of Beijing Institute of Technology 2012年第2期21卷 234-239页

作者：李振华陈家斌马韬 School of automation Beijing Institute of Technology Military Representative Office at North China Optical Instrument company limited

An unsupervised minimum mean square error FIR adaptive filtering （UAF） algorithm is proposed to estimate the system＇ s input signal. The algorithm only uses the system＇ s output signal and noise variance without requiring knowledge of a reference signal. The frequency analysis shows that the UAF is a multi-spot bandpass filter with passing frequency determined by the system＇ s input signal. Namely, the UAF chooses the expected frequency and extremely restricts the unwanted fre- quency signal by using weight-updating scheme in time domain. However, the UAF presents the Gibbs phenomenon since the ideal filter is infinitely long which is unrealizable. The simulation and experimental results show that the UAF could effectively reduce the amplitude of the noise and im- prove the signal to noise ratio.

关键词： unsupervised adaptive filtering mean square error frequency analysis

Visual target tracking based on multi-view feature fusion with online multiple instance learning 36

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Visual target tracking based on multi-view feature fusion wi...

第36届中国控制会议

作者： Weixin Hua Dejun Mu Dawei Guo Hang Liu School of automation Northwestern Polytechnical University company of Shaanxi China Mobile Limited

ISBN: (纸本)9781538629185

The tracking methods under the online multiple instance learning（MIL） framework always use single channel’s information or transform the RGB image to gray image for color video tracking,which may cause the information loss of the color *** addition,the MIL tracker only use the haar-like feature to construct the target appearance and ignore the different samples have different importance to the tracking results,which is argued to susceptible to interference with complex ***,this paper presents an online visual target tracking method based on multi-view feature fusion with joint online multiple instances learning to overcome the disadvantages of the MIL ***,we extract the color histogram feature and haar-like features to construct the two type ***,we compute the bag probability by summing the instance probability in the process of updating the classifiers and construct the strong ***,the object location is achieved by fusing the two type strong *** experimental results show that the proposed method performs better than several other tracking methods like IVT,MIL,OAB and WMIL trackers with smaller central position error on challenging color video sequences.

关键词： target tracking multi-view feature fusion multiple instance learning bag probability classifier

Research and Application of Wireless Temperature Monitoring for Transformer Substation

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Research and Application of Wireless Temperature Monitoring ...

第25届中国控制与决策会议

作者： Qiushi Wang Zhijun Shang Shijie Cui Hongyu Zhang Peng Zeng Shenyang Institute of automation Chinese Academy of Sciences Liaoning Electric Power company limited

ISBN: (纸本)9781467355339

As a very major part in the power grid, it is more and more important to monitor the temperature for the junctions of High Voltage Switchgear, Bus Connector, Outdoor Knife Switch and other important equipments in the Transformer Substation. In this article, based on the actual complex and changeable monitoring environment, we designed Temperature Monitoring System for the Transformer Substation, and expounded the structural design of the system, the hardware design of monitoring device, the process design of the system software, the choice and application of wireless communication protocols in the system, and the comparison and choice of three commonly used antenna. We also compared the Battery-powered and Induction-powered in the technical conditions in this stage, analyzed the actual performance of the two main power supply mode and gave the power design for the Temperature Monitoring System.

关键词： Transformer Substation junctions temperature monitoring hardware design power supply

PI controller relay auto-tuning using delay and phase margin in PMSM drives

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Chinese Journal of Aeronautics 2014年第6期27卷 1527-1537页

作者： Wang Lina Xiao Kun Liliana de Lillo Lee Empringham Pat Wheeler School of automation Science and Electrical Engineering Beihang University Material and Supervision Department State Grid DC Project Construction Company Limited Department of Electrical and Electronic Engineering University of Nottingham

This paper presents an auto-tuning method for a proportion plus integral（PI） controller for permanent magnet synchronous motor（PMSM） drives, which is supposed to be embedded in electro-mechanical actuator（EMA） control module in aircraft. The method, based on a relay feedback with variable delay time, explores different critical points of the system frequency *** Nyquist points of the plant can then be derived from the delay time and filter time *** coefficients of the PI controller can then be obtained by calculation while shifting the Nyquist point to a specific position to obtain the required phase margin. The major advantage of the autotuning method is that it can provide a series of tuning results for different system bandwidths and damping ratios, corresponding to the specification for delay time and phase margin. Simulation and experimental results for the PMSM controller verify the performance of both the current loop and the speed loop auto-tuning.

关键词： Auto-tuning EMA Matrix converters PI control PMSM

Speed Optimization Technology of Process Control in Pickling Line and Tandem Cold Mill

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Speed Optimization Technology of Process Control in Pickling...

第25届中国控制与决策会议

作者： ZHU xiao-yan ZHANG Dian-hua PENG liang-gui WANG kui-yue SONG jun The State Key Laboratory of Rolling and automation Northeastern University Technology Center of Angang Steel company limited

ISBN: (纸本)9781467355339

The speed optimization （SO） control technology used in the pickling line and tandem cold mill （PL-TCM） is introduced. Based on characteristics of the speed control at each section of the PL-TCM, its optimal speed control was ascertained according to the speed control principle and SO strategy. With the loop capacity control principle and stability strategy, the line’s speed was controlled smoothly, which is helpful for improving strip’s quality and quickening the production rhythm. The production results indicate that the output of cold strip has been increased and its shape quality has been greatly improved with the SO control technology.

关键词： Speed optimization pickling line and tandem cold mill looper control cold rolled sheet

Research on the Rectifier Control Method in Drive System

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Research on the Rectifier Control Method in Drive System

第25届中国控制与决策会议

作者： WANG Xiao-yu QIAN Xiao-long Harbin Electric Machinery company limited Key Laboratory of Process Industry automation of MOE Northeastern University

ISBN: (纸本)9781467355339

The selection of oriented vector control method for three-level PWM rectifier is an important factor for getting stable DC voltage. Because the observer has an uncertain initial value, and the rectifier has a large start-up current which may lead to the system failure, while using the virtual flux oriented vector control method for three-level PWM rectifier. For this reason, the grid voltage oriented vector control strategy was adopted to achieve a more effective control on the rectifier. However, the complex mathematical model of this method makes the controller designed difficultly. As the neutral point voltage balance of three-level rectifier can get a good control effect throughout the entire control process, the average current of the neutral point was regarded as zero. Besides, transforming symmetric three-phase parameter to constant DC parameter through appropriate coordinates transform can change the three-phase nonlinear system with time-variable issue into two-phase linear system, and the rational simplification of rectifier model was presented according to the project requirement, which has laid a foundation for the design of controller so as to make it easy for the selection of the PID controller parameters. At last, an effective control on the DC bus voltage and the grid power factor was achieved.

关键词： Three-level PWM Rectifier Oriented Vector Control Power Factor Rational Simplification