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Semi-active vibration control using piezoelectric actuators in smart structures

Jinhao QIU, Hongli JI, Kongjun ZHU

《机械工程前沿（英文）》 2009年第4卷第3期页码 242-251 doi: 10.1007/s11465-009-0068-z

摘要： The piezoelectric materials, as the most widely used functional materials in smart structures, have many outstanding advantages for sensors and actuators, especially in vibration control, because of their excellent mechanical-electrical coupling characteristics and frequency response characteristics. Semi-active vibration control based on state switching and pulse switching has been receiving much attention over the past decade because of several advantages. Compared with standard passive piezoelectric damping, these new semi-passive techniques offer higher robustness. Compared with active damping systems, their implementation does not require any sophisticated signal processing systems or any bulky power amplifier. In this review article, the principles of the semi-active control methods based on switched shunt circuit, including state-switched method, synchronized switch damping techniques, and active control theory-based switching techniques, and their recent developments are introduced. Moreover, the future directions of research in semi-active control are also summarized.

关键词： smart structure semi-active method vibration control piezoelectric actuator

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H_∞ control in the frequency domain for a semi-active floor isolation system

Yundong SHI, Tracy C BECKER, Masahiro KURATA, Masayoshi NAKASHIMA

《结构与土木工程前沿（英文）》 2013年第7卷第3期页码 264-275 doi: 10.1007/s11709-013-0214-x

摘要： A floor isolation system installed in a single floor or room in a fixed base structure is designed to protect equipment. With this configuration, the input motions to the floor isolation from the ground motions are filtered by the structure, leaving the majority of the frequency content of the input motion lower than the predominant frequency of the structure. The floor isolation system should minimize the acceleration to protect equipment; however, displacement must also be limited to save floor space, especially with long period motion. Semi-active control with an control was adopted for the floor isolation system and a new input shaping filter was developed to account for the input motion characteristics and enhance the effectiveness of the control. A series of shake table tests for a semi-active floor isolation system using rolling pendulum isolators and a magnetic-rheological damper were performed to validate the control. Passive control using an oil damper was also tested for comparison. The test results show that the control effectively reduced acceleration for short period motions with frequencies close to the predominant frequency of the structure, as well as effectively reduced displacement for long period motions with frequencies close to the natural frequency of the floor isolation system. The control algorithm proved to be more advantageous than passive control because of its capacity to adjust control strategies according to the different motion frequency characteristics.

关键词： semi-active floor isolation H_∞ control MR damper shaping filter shaking table test

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Design considerations and experimental studies on semi-active smart pin joint

Yancheng LI, Jianchun LI, Bijan SAMALI, Jiong WANG,

《机械工程前沿（英文）》 2009年第4卷第4期页码 363-370 doi: 10.1007/s11465-009-0074-1

摘要： Hostile dynamic loadings such as severe wind storms, earthquakes, and sudden impacts can cause severe damage to many civil engineering structures. An intelligent structural system equipped with smart structural members that are controllable in real-time is an effective solution to structural damage and failure during such situations. Civil intelligent structures with controllable properties to adapt to any changes due to dynamic loadings can lead to effective protection of structures and their occupants. In this paper, design and testing of a semi-active magnetorheological (MR) pin joint, in which the moment resistance can be controlled in real-time by altering the magnetic field, is reported with the view of using it as a potential candidate for smart members in the development of intelligent structures. Design of prototype smart pin joints includes theoretical analysis related to the radius of the rotary plate, the property of MR fluids and the gap between the rotary plate and the casing based on the requirements of the dynamics of MR pin joints. FEM analysis was deployed to study the distribution of the magnetic field along the gap. It is found, from the theoretical analysis and experimental verification, that the MR pin joint with a diameter of 180 mm can produce a torque of up to 30 Nm, which meets requirements for semi-active members in a multi-storey prototype building model in the next stage of research and development.

关键词： magnetorheological (MR) fluids smart pin joint design consideration

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Semi-active fuzzy control of Lali Cable-Stayed Bridge using MR dampers under seismic excitation

Sajad JAVADINASAB HORMOZABAD, Amir K. GHORBANI-TANHA

《结构与土木工程前沿（英文）》 2020年第14卷第3期页码 706-721 doi: 10.1007/s11709-020-0612-9

摘要： Seismic control of cable-stayed bridges is of paramount importance due to their complex dynamic behavior, high flexibility, and low structural damping. In the present study, several semi-active Fuzzy Control Algorithms (FCAs) for vibration mitigation of Lali Cable-Stayed Bridge are devised. To demonstrate the efficiency of the algorithms, a comprehensive nonlinear 3-D model of the bridge is created using OpenSees. An efficient method for connecting MATLAB and OpenSees is devised for applying FCAs to the structural model of the bridge. Two innovative fuzzy rule-bases are introduced. A total of six different fuzzy rule-bases are utilized. The efficiency of the FCAs is evaluated in a comparative manner. The performance of fuzzy control systems is also compared with a sky-hook and a passive-on system. Moreover, the sensitivity of efficiency of control systems to the peak ground acceleration is evaluated qualitatively. In addition, the effect of time lag is also investigated. This study thoroughly examines the efficiency of the FCAs in different aspects. Therefore, the results can be regarded as a general guide to design semi-active fuzzy control systems for vibration mitigation of cable-stayed bridges.

关键词： semi-active control Fuzzy Control Algorithm cable-stayed bridge MR damper Lali Bridge

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基于并联机构及MR阻尼器的多维减振平台半主动控制研究

朱伟,马履中,陈修祥,吴伟光,谢俊

《中国工程科学》 2007年第9卷第11期页码 63-67

摘要：

分析了磁流变阻尼器的力学特性，将其应用于多维减振系统中。采用经典的三平移并联机构作为多维减振平台的主体机构，推导出其位置逆解公式；建立了系统动力学状态方程模型，以运动学方程得到的支路加速度作为输入信号，控制器采用了基于线性二次型最优控制理论的半主动控制算法。考虑到动态过程中机构动力学方程的复杂性，采用稳态方法对并联机构处于某一运动姿态的支路移动副振动进行控制，从而控制了整个平台的振动。仿真结果表明，所采取的控制算法有较好的控制效果。

关键词：并联机构多维减振磁流变阻尼器半主动控制

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Neural network control for earthquake structural vibration reduction using MRD

Khaled ZIZOUNI, Leyla FALI, Younes SADEK, Ismail Khalil BOUSSERHANE

《结构与土木工程前沿（英文）》 2019年第13卷第5期页码 1171-1182 doi: 10.1007/s11709-019-0544-4

摘要： Structural safety of building particularly that are intended for exposure to strong earthquake loads are designed and equipped with high technologies of control to ensure as possible as its protection against this brutal load. One of these technologies used in the protection of structures is the semi-active control using a Magneto Rheological Damper device. But this device need an adequate controller with a robust algorithm of current or tension adjustment to operate which is further discussed in the following of this paper. In this study, a neural network controller is proposed to control the MR damper to eliminate vibrations of 3-story scaled structure exposed to Tōhoku 2011 and Boumerdès 2003 earthquakes. The proposed controller is derived from a linear quadratic controller designed to control an MR damper installed in the first floor of the structure. Equipped with a feedback law the proposed control is coupled to a clipped optimal algorithm to adapt the current tension required to the MR damper adjustment. To evaluate the performance control of the proposed design controller, two numerical simulations of the controlled structure and uncontrolled structure are illustrated and compared.

关键词： MR damper semi-active control earthquake vibration neural network linear quadratic control

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Dynamic characteristics analysis of active constrained layer damping plate with various boundary conditions

Jing LU, Yu XIANG, Qiao NI

《机械工程前沿（英文）》 2011年第6卷第4期页码 449-455 doi: 10.1007/s11465-011-0240-0

摘要：

Considering the direct and converse piezoelectric effect, expressions of piezoelectric membrane internal forces in the piezoelectric constrained layer were given. The control equations of the piezoelectric constrained layer and host plate were obtained in according with the thin plate theory. Based on the layer wised principle, the integrated first order differential equation of an active constrained layer damping (ACLD) plate was derived for the simply supported boundary condition. Then, this method was expanded to the ACLD plate with cantilever boundary condition by virtue of geometric analogy method. Employing the extended homogeneous capacity precision integration approach, a high precision semi-analytical method was proposed to analyze the dynamic characteristics of the ACLD plate with various boundary conditions. The comparison with the literature results has verified the accuracy and effectiveness of the present method.

关键词： active constrained layer damping (ACLD) plate dynamic characteristics semi-analytical method extended homogeneous capacity precision integration approach

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双级驱动半主动隔振系统的可调反共振频率控制器 Research Articles

赵勃1,2,史维佳1,2,王丙泉1,2,谭久彬1,2

《信息与电子工程前沿（英文）》 2021年第22卷第10期页码 1390-1401 doi: 10.1631/FITEE.2000373

摘要：在半导体制造业中，被控对象的动态模型通常是在运动控制前通过扫频方法获得。然而，现有隔离器不能很好隔离扫频时惯性力（频率在0 Hz和固有频率之间）对平台基座的干扰。本文提出一种用于双级驱动半主动隔振系统的可调反共振频率控制器。双级驱动半主动隔振系统具有显著的反共振特性，在一个特定频率——即所谓反共振频率——振幅可降至接近零。本控制器的设计目的是增加一个可调的控制器反共振频率，以充分利用这种独特的反共振特性。实验结果表明了本方案的可行性，闭环传递率从0 Hz到初始反共振频率小于−15 dB。此外，在附加反共振频率附近，闭环传递率小于−30 dB，可通过改变控制器参数实现附加反共振频率在0 Hz至初始反共振频率之间的调节。当平台基座受到脉冲扰动时，使用本文提出的控制器，有效载荷扰动幅度从4 mm/s衰减至0.5 mm/s，降低87.5%。同时，通过跟踪扫频干扰，系统可实时调整反共振频率点，获得良好隔振性能。这表明双级驱动半主动隔振系统和所提控制器可应用于保证超低振动环境，特别是在半导体制造业的扫频工作中。

关键词：半主动隔振；双级驱动；动态吸振；可调反共振频率控制器

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集成增强主动学习混合判别分析模型及其在半监督故障分类中的应用 Research Article

王伟俊1,王云2,王君1,方信昀3,何雨辰1

《信息与电子工程前沿（英文）》 2022年第23卷第12期页码 1814-1827 doi: 10.1631/FITEE.2200053

摘要：故障分类作为过程监控中不可缺少的部分，其性能高度依赖于过程知识的充分性。然而，由于采样条件有限及实验室分析昂贵，数据标签总是难以获取，这可能导致分类性能下降。为了解决这个难题，本文提出一种新的半监督故障分类方法，其中每个未标记样本相对于特定标记数据集的价值采用增强的主动学习来评估。具有高价值的未标记样本将作为训练数据集的补充信息。此外，引入了几个合理的指标和准则大大降低了人工标注的干扰。最后，通过数值例子和田纳西伊士曼过程（TEP）评估了该方法的故障分类有效性。

关键词：半监督；主动学习；集成学习；混合判别分析；故障分类

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Application of semi-analytical finite element method to analyze the bearing capacity of asphalt pavements

Pengfei LIU, Dawei WANG, Frédéric OTTO, Markus OESER

《结构与土木工程前沿（英文）》 2018年第12卷第2期页码 215-221 doi: 10.1007/s11709-017-0401-2

摘要： To facilitate long term infrastructure asset management systems, it is necessary to determine the bearing capacity of pavements. Currently it is common to conduct such measurements in a stationary manner, however the evaluation with stationary loading does not correspond to reality a tendency towards continuous and high speed measurements in recent years can be observed. The computational program SAFEM was developed with the objective of evaluating the dynamic response of asphalt under moving loads and is based on a semi-analytic element method. In this research project SAFEM is compared to commercial finite element software ABAQUS and field measurements to verify the computational accuracy. The computational accuracy of SAFEM was found to be high enough to be viable whilst boasting a computational time far shorter than ABAQUS. Thus, SAFEM appears to be a feasible approach to determine the dynamic response of pavements under dynamic loads and is a useful tool for infrastructure administrations to analyze the pavement bearing capacity.

关键词： semi-analytical finite element method bearing capacity asphalt pavements moving loads dynamic response

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advanced engineering measures on displacement and stress field of surrounding rock in tunnels crossing active

《结构与土木工程前沿（英文）》 doi: 10.1007/s11709-023-0966-x

摘要： Based on significant improvements in engineering materials, three advanced engineering measures have been proposed—super anchor cables, high-strength concrete anti-fault caverns, and grouting modification using high-strength concrete-to resist fault dislocation in the surrounding rock near tunnels crossing active strike-slip faults. Moreover, single- or multiple-joint advanced engineering measures form the local rock mass-anti-fault (LRAF) method. A numerical method was used to investigate the influence of LRAF methods on the stress and displacement fields of the surrounding rock, and the anti-fault effect was evaluated. Finally, the mechanism of action of the anchor cable was verified using a three-dimensional numerical model. The numerical results indicated that the anchor cable and grouting modification reduced the displacement gradient of the local surrounding rock near the tunnels crossing fault. Furthermore, anchor cable and grouting modifications changed the stress field of the rock mass in the modified area. The tensile stress field of the rock mass in the modified anchor cable area was converted into a compressive stress field. The stress field in the modified grouting area changed from shear stress in the fault slip direction to tensile stress in the axial tunnel direction. The anti-fault cavern resisted the dislocation displacement and reduced the maximum dislocation magnitude, displacement gradient, and shear stress. Among the three advanced engineering measures, the anchor cable was the core of the three advanced engineering measures. An anchor cable, combined with other LRAF measures, can form an artificial safety island at the cross-fault position of the rock mass to protect the tunnel. The research results provide a new supporting idea for the surrounding rock of tunnels crossing active strike-slip faults.

关键词： anti-fault effect engineering measures LRAF method stress and displacement field tunnel-crossing active faults

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Uncertainty propagation in dynamics of composite plates: A semi-analytical non-sampling-based approach

Mahdi FAKOOR, Hadi PARVIZ

《结构与土木工程前沿（英文）》 2020年第14卷第6期页码 1359-1371 doi: 10.1007/s11709-020-0658-8

摘要： In this study, the influences of spatially varying stochastic properties on free vibration analysis of composite plates were investigated via development of a new approach named the deterministic-stochastic Galerkin-based semi-analytical method. The material properties including tensile modulus, shear modulus, and density of the plate were assumed to be spatially varying and uncertain. Gaussian fields with first-order Markov kernels were utilized to define the aforementioned material properties. The stochastic fields were decomposed via application of the Karhunen-Loeve theorem. A first-order shear deformation theory was assumed, following which the displacement field was defined using admissible trigonometric modes to derive the potential and kinetic energies. The stochastic equations of motion of the plate were obtained using the variational principle. The deterministic-stochastic Galerkin-based method was utilized to find the probability space of natural frequencies, and the corresponding mode shapes of the plate were determined using a polynomial chaos approach. The proposed method significantly reduced the size of the mathematical models of the structure, which is very useful for enhancing the computational efficiency of stochastic simulations. The methodology was verified using a stochastic finite element method and the available results in literature. The sensitivity of natural frequencies and corresponding mode shapes due to the uncertainty of material properties was investigated, and the results indicated that the higher-order modes are more sensitive to uncertainty propagation in spatially varying properties.

关键词： composite plate spatially varying stochastic properties Galerkin method polynomial chaos approach semi-analytical approach

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Modeling of semi-rigid beam-to-column steel joints under extreme loading

C FANG, B A IZZUDDIN, A Y ELGHAZOULI, D A NETHERCOT

《结构与土木工程前沿（英文）》 2013年第7卷第3期页码 245-263 doi: 10.1007/s11709-013-0215-9

摘要： Joints play an important role in providing ductility for steel-composite structures subject to extreme loading conditions, such as blast, fire and impact. Due to sound energy dissipation capability and fabrication efficiency, semi-rigid joints have increasingly received attention during the last decade. This paper presents a component approach for modeling semi-rigid beam-to-column joints based on Eurocode3, where the post-elastic response, including component strain hardening and ultimate rotational capacity, is also considered. Failure criteria are defined based on the ultimate deformation capacity of components and bolt-rows. The model enables a direct integration of joint response into global frame models with the consideration of axial deformability, such that the interaction between bending moment and axial force within the joints can be realistically captured. In addition, elevated temperature can be considered in the joint model via the degradation of the component response. Through comparisons with available test data, the joint model is shown to have good accuracy, and the failure criteria are found to be reliable yet conservative. The strain hardening response of components is shown to have significant influence on the ultimate bending capacity of the joints, while neglecting it usually leads to a conservative prediction.

关键词： semi-rigid joint component method ductility elevated temperature

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Micromixing performance of the teethed high shear mixer under semi-batch operation

《化学科学与工程前沿（英文）》 2022年第16卷第4期页码 546-559 doi: 10.1007/s11705-021-2069-3

摘要： Semi-batch operated reaction processes are necessary for some competitive reaction systems to achieve a desirable process selectivity and productivity of fine chemical products. Herein the structural and operating parameters of the teethed high shear mixers were adjusted to study the micromixing performance in the semi-batch operated system, using the Villermaux/Dushman reaction system. The results indicate that the rising of the rotor speed and the number of rotor teeth, the decrease of the width of the shear gap and the radial distance between the feed position and the inner wall of stator can enhance the micromixing level and lead to the decrease of the segregation index. Additionally, computational fluid dynamics calculations were carried out to disclose the evolution of the flow pattern and turbulent energy dissipation rate of the semi-batch operated high shear mixer. Furthermore, the correlation was established with a mean relative error of 8.05% and R² of 0.955 to fit the segregation index and the parameters studied in this work, which can provide valuable guidance on the design and optimization of the semi-batch operated high shear mixers in practical applications.

关键词： high shear mixer semi-batch operation micromixing performance Villermaux/Dushman system segregation index

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基于迭代算法的有源电力滤波器谐波电流实时检测新方法

李自成,孙玉坤

《中国工程科学》 2006年第8卷第1期页码 46-50

摘要：

目前，已经提出了多种有源电力滤波器谐波及无功电流检测方法，尽管这些方法各有特点，但都存在着难以克服的问题，如计算量大，实时性差，检测精度不高等。文章在负载电流分析的基础上，提出了一种基于迭代算法的有源电力滤波器谐波电流实时检测方法，该方法具有计算量非常小，实时性好，检测精度高等特点。理论分析与仿真研究证实了该方法的正确性。

关键词：有源电力滤波器谐波电流有功电流无功电流