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关键词

Doherty功率放大器；输出功率回退；输出阻抗；网络相位 1

RLC网络；谐振性质；振荡特性；幅频特性 1

SOFC 1

交流阻抗 1

人机协作 1

侧边曲线方程 1

共振检测 1

可调阶梯阻抗谐振器；液晶；共面波导 1

吉赫兹横电磁波传输室(GTEM Cell) 1

固体氧化物材料 1

声学综合检测 1

复合材料无损检测 1

岩石-炸药匹配 1

振动分析 1

故障限流器（FCL）；FCL阻抗；短路电流；故障电流；电力系统 1

斧形过渡块 1

机器人装配 1

机械阻抗分析 1

模糊控制；阻抗控制；干扰观测器；参数不确定性；电液执行器 1

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Spectral element modeling based structure piezoelectric impedance computation and damage identification

Zhigang GUO, Zhi SUN

《结构与土木工程前沿（英文）》 2011年第5卷第4期页码 458-464 doi: 10.1007/s11709-011-0133-7

摘要： This paper presents a numerical simulation study on electromechanical impedance technique for structural damage identification. The basic principle of impedance based damage detection is structural impedance will vary with the occurrence and development of structural damage, which can be measured from electromechanical admittance curves acquired from PZT patches. Therefore, structure damage can be identified from the electromechanical admittance measurements. In this study, a model based method that can identify both location and severity of structural damage through the minimization of the deviations between structural impedance curves and numerically computed response is developed. The numerical model is set up using the spectral element method, which is promised to be of high numerical efficiency and computational accuracy in the high frequency range. An optimization procedure is then formulated to estimate the property change of structural elements from the electric admittance measurement of PZT patches. A case study on a pin-pin bar is conducted to investigate the feasibility of the proposed method. The results show that the presented method can accurately identify bar damage location and severity even when the measurements are polluted by 5% noise.

关键词： PZT piezoelectric impedance optimization spectral element damage identification

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stack configuration on interface resistances in reverse electrodialysis by in situ electrochemical impedance

《环境科学与工程前沿（英文）》 2022年第16卷第4期 doi: 10.1007/s11783-021-1480-9

摘要：

• RED performance and stack resistance were studied by EIS and LSV.

关键词： Reverse electrodialysis Electrochemical impedance spectroscopy Concentration polarization Spacer shadow effect

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Fuzzy force control of constrained robot manipulators based on impedance model in an unknown environment

LIU Hongyi, WANG Fei, WANG Lei

《机械工程前沿（英文）》 2007年第2卷第2期页码 168-174 doi: 10.1007/s11465-007-0028-4

摘要： To precisely implement the force control of robot manipulators in an unknown environment, a control strategy based on fuzzy prediction of the reference trajectory in the impedance model is developed. The force tracking experiments are executed in an open-architecture control system with different tracking velocities, different desired forces, different contact stiffnesses and different surface figurations. The corresponding force control results are compared and analyzed. The influences of unknown parameters of the environment on the contact force are analyzed based on experimental data, and the tunings of predictive scale factors are illustrated. The experimental results show that the desired trajectory in the impedance model is predicted exactly and rapidly in the cases that the contact surface is unknown, the contact stiffness changes, and the fuzzy force control algorithm has high adaptability to the unknown environment.

关键词： predictive tracking corresponding stiffness algorithm

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Detection of void and metallic inclusion in 2D piezoelectric cantilever beam using impedance measurements

S. SAMANTA, S. S. NANTHAKUMAR, R. K. ANNABATTULA, X. ZHUANG

《结构与土木工程前沿（英文）》 2019年第13卷第3期页码 542-556 doi: 10.1007/s11709-018-0496-0

摘要： The aim of current work is to improve the existing inverse methodology of void-detection based on a target impedance curve, leading to quick-prediction of the parameters of single circular void. In this work, mode-shape dependent shifting phenomenon of peaks of impedance curve with change in void location has been analyzed. A number of initial guesses followed by an iterative optimization algorithm based on univariate method has been used to solve the problem. In each iteration starting from each initial guess, the difference between the computationally obtained impedance curve and the target impedance curve has been reduced. This methodology has been extended to detect single circular metallic inclusion in 2D piezoelectric cantilever beam. A good accuracy level was observed for detection of flaw radius and flaw-location along beam-length, but not the precise location along beam-width.

关键词： piezoelectricity impedance curve mode shapes inverse problem flaw detection curve shifting

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基于阻抗控制的人机协作范式研究及其机器人装配应用 Article

赵兴炜, 陈沂洺, 钱璐, 陶波, 丁汉

《工程（英文）》 2023年第30卷第11期页码 83-92 doi: 10.1016/j.eng.2022.08.022

摘要：

人-机器人协作由于人和机器人的优势互补而成为一个新兴的研究领域。本文提出了一种基于阻抗控制人机协作理论框架。在人机理论协框架下，人是决策者，机器人是执行者，装配任务提供环境约束。机器人是执行装配动作的主要执行者，具有位置控制、拖动控制、正阻抗控制和负阻抗控制等方式。为了揭示人机协作框架的特点，本文讨论了不同控制模式的切换条件图和人机协同耦合系统的稳定性分析。最后进行了人机协作装配实验，在装配公差为0.08 mm或配合过盈配合时，均可完成装配任务。实验表明，人机协同装配具有人与机器人的互补优势，能够有效地完成复杂的装配任务。

关键词：人机协作阻抗控制机器人装配

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Valveless pumping using a two-stage impedance pump

V. C.-C. LEE, Y. A. ABAKR, K.-C. WOO

《机械工程前沿（英文）》 2013年第8卷第3期页码 311-318 doi: 10.1007/s11465-013-0270-x

摘要：

Impedance pump is defined as a type of valveless pumping mechanism, where an elastic tube is joined with a tube of different impedance, a periodic asymmetrical compression on part of the elastic tube will produce a unidirectional flow. Numerical and experimental studies had been conducted in the past, but little experimental work was found to exploit the principle of multi-stage impedance pumping for fluid transportation. This paper concentrates on the fluid behavior for an open-loop two-stage system experimentally. The aim of this work is to have an insight on the deliverable head and pumping rate of an open-loop two-stage impedance pumping system. This paper generally investigates the effect of different parameters towards the generation of unidirectional flows and composite flow of two opposite directions. Results obtained are of significant values.

关键词： valveless pumping open-loop two-stage unidirectional composite

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电力系统中对称和/或不对称故障的限流器阻抗优化新方法 None

Mahmoud MODARESI, Hamid LESANI

《信息与电子工程前沿（英文）》 2018年第19卷第2期页码 297-307 doi: 10.1631/FITEE.1601689

摘要：为给电力网络设计者选择故障限流器（fault current limiters，FCLs）的阻抗类型和阻值，提出一种基于其在网络中的位置计算最佳FCL阻值的新方法。由于阻抗的复杂性，需同时考虑FCL阻抗实部和虚部的代价。FCL阻抗优化的目标函数，是以最小化代价最大限度减少故障电流。虽然最佳FCL阻抗值的计算受其在网络中位置的影响，但选取FCL位置的方法并非本文重点。该FCL阻抗优化方法可用于任何具有对称和/或不对称故障的网络。以一个14总线IEEE网络为例解释该过程。该网络采用的最优FCL阻抗是同时考虑FCL阻抗实部和虚部的大范围代价计算得到的。

关键词：故障限流器（FCL）；FCL阻抗；短路电流；故障电流；电力系统

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An investigation on stress distribution effect on multi- piezoelectric energy harvesters

Hailu YANG, Dongwei CAO

《结构与土木工程前沿（英文）》 2017年第11卷第3期页码 301-307 doi: 10.1007/s11709-017-0404-z

摘要： With the fast development of piezoelectric materials and due to its green and renewable characteristics, the piezoelectric energy harvesting technology has been paid more and more attention by pavement engineers. The stress distribution will significantly affect the piezoelectric material performance. In this paper, the effects of multiple piezoelectric elements on the generation of electrical energy and output power are studied. In the case of constant external load, the number of the piezoelectric units does not necessarily produce more energy. When the same multi piezoelectric units work together, if the stress state of the piezoelectric units is different, the total output energy affected by the connection mode. For uneven stress distribution, the optimal output mode is that each of the piezoelectric units rectified before connected in parallel.

关键词： piezoelectric transducer uneven stress impedance matching optimal energy output

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Advances in tissue state recognition in spinal surgery: a review

Hao Qu, Yu Zhao

《医学前沿（英文）》 2021年第15卷第4期页码 575-584 doi: 10.1007/s11684-020-0816-3

摘要： Spinal disease is an important cause of cervical discomfort, low back pain, radiating pain in the limbs, and neurogenic intermittent claudication, and its incidence is increasing annually. From the etiological viewpoint, these symptoms are directly caused by the compression of the spinal cord, nerve roots, and blood vessels and are most effectively treated with surgery. Spinal surgeries are primarily performed using two different techniques: spinal canal decompression and internal fixation. In the past, tactile sensation was the primary method used by surgeons to understand the state of the tissue within the operating area. However, this method has several disadvantages because of its subjectivity. Therefore, it has become the focus of spinal surgery research so as to strengthen the objectivity of tissue state recognition, improve the accuracy of safe area location, and avoid surgical injury to tissues. Aside from traditional imaging methods, surgical sensing techniques based on force, bioelectrical impedance, and other methods have been gradually developed and tested in the clinical setting. This article reviews the progress of different tissue state recognition methods in spinal surgery and summarizes their advantages and disadvantages.

关键词： spinal surgery tissue state recognition image force sensing bioelectrical impedance

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基于扩展干扰观测器的电液执行器的模糊阻抗控制 Regular Papers-Research Articles

Ming-jie LI, Jian-hua WEI, Jin-hui FANG, Wen-zhuo SHI, Kai GUO

《信息与电子工程前沿（英文）》 2019年第20卷第9期页码 1221-1233 doi: 10.1631/FITEE.1800155

摘要：在本文中，我们同时处理遭受外干扰及参数不确定影响的单出杆电液执行器的速度控制和力控制。在某些应用中，速度控制和力控制两者都有要求。阻抗控制和扩展干扰观测器的结合可以解决该问题。阻抗控制可调节执行器的速度和输出力之间的动态关系，有助于执行器与作用环境或者工件间避免冲击和保持合适的接触力。阻抗规则参数可由模糊算法调节。扩展干扰观测器被用于补偿外部干扰和参数不确定性，实现精确的速度跟踪。为扩展干扰器的开发，提出精确的负载力动力学模型。分析了系统稳定性。实验数据表明所提控制算法具有高精度速度跟踪性能，同时具有良好的力调节能力，在工程机械和装配中具有较大应用前景。

关键词：模糊控制；阻抗控制；干扰观测器；参数不确定性；电液执行器

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Review of pantograph and catenary interaction

Weihua ZHANG, Dong ZOU, Mengying TAN, Ning ZHOU, Ruiping LI, Guiming MEI

《机械工程前沿（英文）》 2018年第13卷第2期页码 311-322 doi: 10.1007/s11465-018-0494-x

摘要：

The application of electrified railway directly promotes relevant studies on pantograph-catenary interaction. With the increase of train running speed, the operating conditions for pantograph and catenary have become increasingly complex. This paper reviews the related achievements contributed by groups and institutions around the world. This article specifically focuses on three aspects: The dynamic characteristics of the pantograph and catenary components, the systems’ dynamic properties, and the environmental influences on the pantograph-catenary interaction. In accordance with the existing studies, future research may prioritize the task of identifying the mechanism of contact force variation. This kind of study can be carried out by simplifying the pantograph-catenary interaction into a moving load problem and utilizing the theory of matching mechanical impedance. In addition, developing a computational platform that accommodates environmental interferences and multi-field coupling effects is necessary in order to further explore applications based on fundamental studies.

关键词： electrified railway pantograph and catenary interaction contact force variation moving load problem mechanical impedance multi-field

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A facile synthesis of high activity cube-like Pt/carbon composites for fuel cell application

Reza B. MOGHADDAM, Samaneh SHAHGALDI, Xianguo LI

《能源前沿（英文）》 2017年第11卷第3期页码 245-253 doi: 10.1007/s11708-017-0492-4

摘要： High activity catalyst with simple low-cost synthesis is essential for fuel cell commercialization. In this study, a facile procedure for the synthesis of cube-like Pt nanoparticle (Pt ) composites with high surface area carbon supports is developed by mixing precursor of Pt with carbon supports in organic batches, hence, one pot synthesis. The Pt grow with Vulcan XC-72 or Ketjen black, respectively, and then treated for 5.5 h at 185ºC (i.e., Pt /V and Pt /K). The resulting particle sizes and shapes are similar; however, Pt /K has a larger electrochemical active surface area (EASA) and a remarkably better formic acid (FA) oxidation performance. Optimization of the Pt /K composites leads to Pt /K that has been treated for 10 h at 185ºC. With a larger EASA, Pt /K is also more active in FA oxidation than the other Pt /K composites. Impedance spectroscopy analysis of the temperature treated and as-prepared (i.e., untreated) Pt /K composites indicates that Pt /K is less resistive, and has the highest limiting capacitance among the Pt /K electrodes. Consistently, the voltammetric EASA is the largest for Pt /K. Furthermore, Pt /K is compared with two commercial Pt/C catalysts, Tanaka Kikinzoku Kogyo (TKK), and Johnson Matthey (JM)Pt/C catalysts. The TKK Pt/C has a higher EASA than Pt /K, as expected from their relative particles sizes (3–4 nm vs. 6–7 nm for Pt /K), however, Pt /K has a significantly better FA oxidation activity.

关键词： synthesis cube-like Pt Pt/C composite catalyst impedance

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GTEM Cell斧形过渡块侧边曲线方程的算法

周旭

《中国工程科学》 2003年第5卷第9期页码 36-38

摘要：

为便于加工，以往的吉赫兹横电磁波传输室(GTEM Cell)过渡接头中斧形过渡块均采用近似设计，即侧边取直线。这样做的结果是传输损耗曲线在过渡段的分布不理想。基于修正的目的，首次给出了精确的斧形块侧边之连续曲线方程。

关键词：吉赫兹横电磁波传输室(GTEM Cell) 斧形过渡块侧边曲线方程阻抗匹配

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SOFC关键材料电化学表征方法

樊丽权,赵二庆,高克卿,熊岳平

《中国工程科学》 2013年第15卷第2期页码 50-56

摘要：

固体氧化物燃料电池（SOFC）是全固态的化学发电装置，其构成材料固体氧化物对SOFC性能的影响尤为重要。本文从材料对SOFC电化学性能影响的视角出发，立足电化学、固体电化学的基本原理，概述了SOFC构成材料的电化学表征方法，并将一些研究积累赘述文中，希望有利于材料的进一步研究。

关键词：固体氧化物材料直流极化交流阻抗 SOFC

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声学综合无损检测技术

陈积懋

《中国工程科学》 2000年第2卷第4期页码 64-69

摘要：

论述了检测复合材料和胶接结构不连续（缺陷）的新型多模综合无损检测技术。该技术以声与超声检测技术为基础，包含五种不同检测模式，用以检测复合材料与胶接结构的失粘、脱粘、分层、疏松、夹芯压皱及其他缺陷。它适用于复合材料与构件的制造、维修和使用现场。它的适用对象范围广泛，几乎覆盖了现有常用的复合材料和胶接结构。它的检测可靠性高，重复精度好。文章还讨论了组成多膜声学综合胶接检测仪的五种不同检测模式的原理，并从我们和国内外同行的大量实践经验出发，说明了综合无损检测技术的巨大发展前景。

关键词：声学综合检测综合无损检测复合材料无损检测机械阻抗分析振动分析共振检测