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期刊论文 7

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2022 2

2017 1

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2002 1

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12相整流 1

交直流同时供电 1

参数初值整定；自适应鲁棒控制；并联机构；气缸 1

双绕组交直流发电机 1

同步注浆 1

掘进参数 1

泥水循环 1

泥水盾构 1

独立电力系统 1

电力集成 1

盾构姿态 1

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Deviation correction strategy for the earth pressure balance shield based on shield–soil interactions

《机械工程前沿（英文）》 2022年第17卷第2期 doi: 10.1007/s11465-022-0676-4

摘要： The control system presently used in shield posture rectification is based on driver experience, which is marginally reliable. The study of the related theory is flawed. Therefore, a decision-making approach for the deviation correction trajectory and posture rectification load for an earth pressure balance (EPB) shield is proposed. A calculation model of posture rectification load of an EPB shield is developed by considering the interactions among the cutter head, shield shell, and ground. The additional position change during the shield attitude correction is highlighted. The posture rectification loads and shield behaviors results can be solved by the proposed method. The influences of the stratum distribution (i.e., bedrock height in the upper-soft and lower-hard strata) on shield behaviors and posture rectification loads are analyzed. Results indicated that the increase of pitch angle in the upper-soft and lower-hard strata causes a sharp rise in vertical displacement. The bedrock height increases the magnitudes of the required posture rectification moments when h_r/D > 0.5. For a tunnel with h_r/D ≤ 0.5, the variation of h_r/D has little effect on the posture rectification moments. Finally, the posture rectifying curves based on the theoretical model are compared with the target ones based on the double circular arc interpolation method. The required results can be obtained regardless of the soil–rock compound stratum distribution. The maximum rectification moment in the rock layer is almost 12.6 times that in the soil layer. Overall, this study provides a valuable reference for moment determination and the trajectory prediction of posture rectification in compound strata.

关键词： additional position change deviation correction trajectory earth pressure balance shield mechanical model posture rectification

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A valveless piezoelectric pump with novel flow path design of function of rectification to improve energy

《机械工程前沿（英文）》 2022年第17卷第3期 doi: 10.1007/s11465-022-0685-3

摘要： Existing valveless piezoelectric pumps are mostly based on the flow resistance mechanism to generate unidirectional fluid pumping, resulting in inefficient energy conversion because the majority of mechanical energy is consumed in terms of parasitic loss. In this paper, a novel tube structure composed of a Y-shaped tube and a ȹ-shaped tube was proposed considering theory of jet inertia and vortex dissipation for the first time to improve energy efficiency. After verifying its feasibility through the flow field simulation, the proposed tubes were integrated into a piezo-driven chamber, and a novel valveless piezoelectric pump with the function of rectification (NVPPFR) was reported. Unlike previous pumps, the reported pump directed the reflux fluid to another flow channel different from the pumping fluid, thus improving pumping efficiency. Then, mathematical modeling was established, including the kinetic analysis of vibrator, flow loss analysis of fluid, and pumping efficiency. Eventually, experiments were designed, and results showed that NVPPFR had the function of rectification and net pumping effect. The maximum flow rate reached 6.89 mL/min, and the pumping efficiency was up to 27%. The development of NVPPFR compensated for the inefficiency of traditional valveless piezoelectric pumps, broadening the application prospect in biomedicine and biology fields.

关键词： composite tube valveless piezoelectric pump rectification energy efficiency

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Construction Activity Analysis of Workers Based on Human Posture Estimation Information

Xuhong Zhou,Shuai Li,Jiepeng Liu,Zhou Wu,Yohchia Frank Chen,

《工程（英文）》 doi: 10.1016/j.eng.2023.10.004

摘要： Identifying workers’ construction activities or behaviors can enable managers to better monitor labor efficiency and construction progress. However, current activity analysis methods for construction workers rely solely on manual observations and recordings, which consumes considerable time and has high labor costs. Researchers have focused on monitoring on-site construction activities of workers. However, when multiple workers are working together, current research cannot accurately and automatically identify the construction activity. This research proposes a deep learning framework for the automated analysis of the construction activities of multiple workers. In this framework, multiple deep neural network models are designed and used to complete worker key point extraction, worker tracking, and worker construction activity analysis. The designed framework was tested at an actual construction site, and activity recognition for multiple workers was performed, indicating the feasibility of the framework for the automated monitoring of work efficiency.

关键词： Pose estimation Activity analysis Object tracking Construction workers Automatic systems

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Piezoelectric diffuser/nozzle micropump with double pump chambers

WANG Wei, ZHANG Ying, TIAN Li, CHEN Xiaojie, LIU Xiaowei

《机械工程前沿（英文）》 2008年第3卷第4期页码 449-453 doi: 10.1007/s11465-008-0076-4

摘要： To eliminate check valve fatigue and valve clogging, diffuser/nozzle elements are used for flow rectification in a valveless diffuser/nozzle micropump instead of valves. However, the application of this type of micropump is restricted because of its pulsating or periodic flow and low pump flux. In this paper, a diffuser/nozzle Si/Glass micropump with two pump chambers by IC and MEMS technology is designed. The fabrication process requires only one mask and one etch step, so that the fabrication has the advantages of low cost, short processing period, and facilitation of miniaturization. The pump is equipped with a glass cover board so as to conveniently observe the flow status. Pump-chambers and diffuser elements are fabricated by the anisotropic KOH-etch technique on the silicone substrate, and the convex corner is designed to compensate for an anisotropic etch. The driving force of the micropump is produced by the PZT piezoelectric actuator. The pump performance with both actuators actuated in anti- or same-phase mode is also researched. The result indicates that the micropump achieves great performance with the actuators working at anti-phase. This may be because the liquid flows steadily, pulse phenomenon is very weak, and the optimal working frequency, pump back pressure, and flow rate are both double that of the pump driven in same-phase.

关键词： diffuser/nozzle Si/Glass phenomenon rectification diffuser/nozzle micropump frequency

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交直流电力集成技术

马伟明

《中国工程科学》 2002年第4卷第12期页码 53-59

摘要：

建立了新型电机的数学模型，为解决关键技术问题提供了理论基础。查明了发电机整流系统特有的低频功率振荡的机理，得出了稳定判据及解决稳定问题的技术措施；通过合理设计，可控制直流电压的浮动范围；综合治理整流过程引起的交流谐波和直流脉动，提高了系统的EMC性能；巧妙地处理了系统的强非线性，从而得出了直流短路和交直流同时短路的冲击电流解析式；提出了根据整流装置输入、输出电压波形进行实时在线故障诊断的原理和方法。在此基础上，将定子3相绕组、12相绕组、整流装置、励磁系统、励磁调节器等集于一体，功研制出性能优良的交直流发电机，能同时提供高品质交直流电源，为独立电力系统的集成化奠定了基础。

关键词：电力集成双绕组交直流发电机 12相整流交直流同时供电独立电力系统

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复杂条件下的大直径泥水盾构掘进参数控制

王百泉,任勇,金仲祥,古艳旗

《中国工程科学》 2010年第12卷第12期页码 65-69

摘要：

对盾构掘进参数进行了详细试验，对不同地层条件下刀盘扭矩与刀具磨损情况之间的关系进行了详细分析，并探讨了盾构姿态的控制方法，同时对同步注浆参数及泥水循环系统做以简要介绍，总结了掘进参数、泥浆密度等在盾构掘进中的重要地位。

关键词：泥水盾构掘进参数同步注浆泥水循环盾构姿态

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含参数初值整定和自适应鲁棒方法的3-RPS气动并联平台位姿控制 Article

Guo-liang TAO,Ce SHANG,De-yuan MENG,Chao-chao ZHOU

《信息与电子工程前沿（英文）》 2017年第18卷第3期页码 303-316 doi: 10.1631/FITEE.1500353

摘要：本文讨论了关于气缸驱动的3-RPS并联平台的一种控制方法。研究对象使用气动比例方向阀控制各驱动气缸，并建立了系统的运动学和动力学模型，采用基于反步法和在线参数辨识的自适应鲁棒控制器作为主要控制方式。同时为了满足对系统未建模部分和参数估计误差导致的干扰，将直接自适应快速补偿集成与控制器的设计中。为了避免因为在平台运动过程等实际工况中负载变化对性能造成的影响，提出了一种参数初值整定模式，提升了控制算法的适应性。通过采用这些方法，并联平台位姿轨迹跟踪性能的频响和精度均有了提升，并且负载和约束内力对平台控制性能造成的不良影响也得到了消除。不同工况下的实验显示了所设计的控制方法的良好性能，使整体平均相对误差减小到1%以内。

关键词：参数初值整定；自适应鲁棒控制；并联机构；气缸

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标题作者时间类型操作

Deviation correction strategy for the earth pressure balance shield based on shield–soil interactions

期刊论文

A valveless piezoelectric pump with novel flow path design of function of rectification to improve energy

期刊论文

Construction Activity Analysis of Workers Based on Human Posture Estimation Information

Xuhong Zhou,Shuai Li,Jiepeng Liu,Zhou Wu,Yohchia Frank Chen,

期刊论文

Piezoelectric diffuser/nozzle micropump with double pump chambers

WANG Wei, ZHANG Ying, TIAN Li, CHEN Xiaojie, LIU Xiaowei