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期刊论文 19

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2021 1

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2006 2

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关键词

RLC网络；谐振性质；振荡特性；幅频特性 1

事件触发控制；分段仿射系统；线性矩阵不等式；执行器饱和；H∞性能 1

交通导致振动 1

体变模量 1

信号平稳化 1

分层 1

压缩 1

固结 1

大桥 1

寿命预测 1

悬索 1

振幅分析 1

探地雷达 1

斜拉 1

最优一致性控制；多智能体系统；非零和博弈；自适应动态规划；输入饱和；脱策强化学习；策略迭代 1

桥接 1

沙丘 1

疲劳 1

纤维金属层板 1

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Controlling nested wrinkle morphology through the boundary effect on narrow-band thin films

Hanyang XU, Tielin SHI, Guanglan LIAO, Qi XIA

《机械工程前沿（英文）》 2019年第14卷第2期页码 235-240 doi: 10.1007/s11465-017-0458-6

摘要： We describe the formation of nested wrinkles created by the thermal mismatch between a narrow-band thin film and a compliant substrate. When a film is described as “narrow-band”, it literally means that the film band width is much shorter than its length; more precisely, it means that the width is comparable with the wavelength of the wrinkles. A silicon mask was used during film sputtering to create narrow-band films on poly (dimethylsiloxane) substrate, thus creating regular boundaries to steer local stresses and control wrinkle morphology. Disordered nano-scale wrinkles were found nested within highly ordered micro-scale sinusoidal wrinkles. The formation of nested wrinkles was explained through the amplitude and wavelength saturation of nano-scale wrinkles. The disordered morphology of nano-scale wrinkles and the highly ordered morphology of micro-scale wrinkles were explained by using the boundary effect.

关键词： nested and hierarchical wrinkles morphology amplitude saturation boundary effect

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Stress field near circular-arc interface crack tip based on electric saturation concept

Longchao DAI, Xinwei WANG

《机械工程前沿（英文）》 2009年第4卷第3期页码 320-325 doi: 10.1007/s11465-009-0042-9

摘要： Within the framework of nonlinear electroelasticity, the anti-plane problem of a circular-arc interfacial crack between a circular piezoelectric inhomogeneity and an infinite piezoelectric matrix subjected to a far-field uniform loading is investigated by an electrical strip saturation model, the complex variable method, and the method of analytical continuation. Explicit closed form expressions for the complex potentials in both the matrix and the inclusion, and the stress intensity factor at the crack tip are presented. Comparison with some related solutions based on the linear electroelastic theory shows the validity of the present solutions

关键词： piezoelectric material arc crack strip saturation stress intensity factor

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Continuous modeling of soil morphology —thermomechanical behavior of embankment dams

Bettina ALBERS, Krzysztof WILMANSKI

《结构与土木工程前沿（英文）》 2011年第5卷第1期页码 11-23 doi: 10.1007/s11709-010-0081-7

摘要： Macroscopic modeling of soils is based on a number of properties that refer to the mesoscopic morphology. The most fundamental parameters of this art are: 1) coupling parameters between partial stresses of components and deformations of components, 2) porosities, 3) saturation, and 4) permeability and diffusivity, tortuosity. The main aim of this paper is to present in juxtaposition continuous one-, two-, and three-component models of geomaterials appearing in construction of embankment dams. In particular, the above mentioned features, especially saturation with water and seepage problems, modeling of fluidization yielding piping, and generalizations of the Darcy law and changes of porosity, are presented.

关键词： thermomechanical modeling soil morphology saturation porosity

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Experimental determination of Cd

Farhah Amalya ISMAIL, Ahmad Zaharin ARIS

《环境科学与工程前沿（英文）》 2013年第7卷第3期页码 356-364 doi: 10.1007/s11783-013-0488-1

摘要： Carbonate shells have an astonishing ability in the removal of Cd in a short time period with emphasis on being a low cost adsorbent. In the present study, the sorption capacity of carbonate shells was studied for Cd in batch experiments. The influence of different carbonate shell sizes and physico-chemical factors were evaluated and the results were analyzed for its correlation matrices by using Predictive Analytics Software (PASW). The mineralogy state of aqueous solution regarding the saturation index was simulated using PHREEQC to identify the Cd uptake mechanism. The Cd uptake rates were calculated as well as Ca , concentration, pH, ambient humidity and temperature were measured. Cd removal of 91.52% was achieved after 5 h adsorption. The adsorption efficiencies were significantly influenced by pH as they increased with the increase of pH from acidic solution (5.50±0.02) to slightly alkaline (7.60±0.05). In addition, the mineralogy state of aqueous solution calculated from PHREEQC confirmed that the increment of Ca and concentrations in solution was attributed to the dissolution of carbonate shells. Moreover, the ion exchange adsorption mechanism of Cd toward Ca was identified as the process involved in Cd uptake.

关键词： carbonate shell cadmium heavy metal adsorption mechanism saturation state

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高饱和土固结及饱和度对土体固结的影响

金志高

《中国工程科学》 2004年第6卷第9期页码 73-76

摘要：

以Terzaghi土体固结理论和Biot固结理论为基础，按饱和度不同的分类，研究了高饱和土固结机理及过程，深入分析了高饱和土饱和度变化对孔隙流体压缩性的影响，以及由此影响到高饱和土的固结全过程。

关键词：固结饱和度体变模量压缩

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Research on direct digital process of inductance sensor

WANG Xuan-ze, YANG Lian-gen, ZHONG Yu-ning

《机械工程前沿（英文）》 2006年第1卷第3期页码 317-322 doi: 10.1007/s11465-006-0023-1

摘要： The equivalent circuit of inductance sensor is analyzed. Amplitude-displacement and phase-displacement equations are deduced for non-ideal carrier wave and inductance parameters. Simulation computation shows the corresponding digital curves. Considering that the traditional process method is an approximate one, a new method is presented to simultaneously obtain the amplitude and phase of output signal of sensor by simultaneity A/D and ellipse fit arithmetic. According to the characteristic of the amplitude-displacement and phase-displacement curves, we obtain displacement by phase and amplitude respectively when the sensor is close to the zero point position and away from other positions on the basis of the experiment. The experiment showed that this method can improve precision of measurement, and it can also work for the whole linear range of sensors even if the magnification is very high.

关键词： traditional corresponding phase-displacement Amplitude-displacement characteristic

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输入饱和下多智能体系统最优一致性控制：一类非零和博弈方法 Research Article

李洪阳1,2,魏庆来1,2,3

《信息与电子工程前沿（英文）》 2022年第23卷第7期页码 1010-1019 doi: 10.1631/FITEE.2200010

摘要：本文针对输入饱和下的多智能体系统，提出一种最优一致性控制方法。引入多智能体博弈理论，将最优一致性控制问题转化为多智能体非零和博弈。之后，通过求解具有非二次输入能量项的耦合Hamilton–Jacobi–Bellman（HJB）方程，实现Nash平衡。提出脱策强化学习方法，在系统模型未知情况下获得Nash平衡解；引入评判神经网络和执行神经网络实现所提方法。理论分析显示迭代控制律收敛到Nash平衡。仿真实验验证了所提方法的有效性。

关键词：最优一致性控制；多智能体系统；非零和博弈；自适应动态规划；输入饱和；脱策强化学习；策略迭代

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Application of a Novel Fuzzy Clustering Method Based on Chaos Immune Evolutionary Algorithm for Edge Detection in Image Processing

《机械工程前沿（英文）》 2006年第1卷第1期页码 85-89 doi: 10.1007/s11465-005-0023-6

摘要：

A novel fuzzy clustering method based on chaos immune evolutionary algorithm (CIEFCM) is presented to solve fuzzy edge detection problems in image processing. In CIEFCM, a tiny disturbance is added to a filial generation group using a chaos variable and the disturbance amplitude is adjusted step by step, which greatly improves the colony diversity of the immune evolution algorithm (IEA). The experimental results show that the method not only can correctly detect the fuzzy edge and exiguous edge but can evidently improve the searching efficiency of fuzzy clustering algorithm based on IEA.

关键词： disturbance amplitude disturbance diversity generation processing

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Flow behavior of liquid-solid coupled system of piezoelectric micropump

LU Lijun, WU Jiankang

《机械工程前沿（英文）》 2008年第3卷第1期页码 50-54 doi: 10.1007/s11465-008-0003-8

摘要： This paper employs a shallow water model and the finite element method to approximate periodical flows of a micropump to a two-dimensional thickness-averaged flow. A liquid-solid coupled system equation of the micropump is presented. Through the mode analysis of the liquid-solid coupled system, the first-order natural frequency, diaphragm vibration shape and amplitude-frequency relationship are obtained. The vibration response of the diaphragm is calculated when an external electric field is applied. Based on the thickness-averaged flow equation, the periodical flow of the micropump is studied using the finite volume method to investigate the flow behavior and flow rate-frequency characteristics. Numerical results indicate that an optimal working frequency can be obtained, at which the flow rate of the micropump achieves the maximum when the external electric voltage is fixed.

关键词： amplitude-frequency relationship first-order micropump diaphragm vibration electric

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Air-bearing position optimization based on dynamic characteristics of ultra-precision linear stages

CHEN Xuedong, LI Zhixin

《机械工程前沿（英文）》 2008年第3卷第4期页码 400-407 doi: 10.1007/s11465-008-0060-z

摘要： Air-bearings are installed between the stator and the mover of ultra-precision linear stages to suppress vibration and mechanical contact. Spring-damping elements are used to emulate the complex interaction of the finite element model (FEM) developed in this paper and the system dynamic behaviors are analyzed. Through the experimental modal test, the validity and reliability of the model are proven. However, the dynamic characteristics including mode frequency, mode shape, and response amplitude are obviously changed with the position of air-bearings. The combined optimization method is used to optimize the air-bearings position. The best and worst positions are obtained using the dynamic characteristic analysis. The method can be generalized to the connection position of different components in manufacture elements and to implement the system dynamic characteristics optimization when the connection position can be changed.

关键词： manufacture different interaction air-bearings response amplitude

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Separation and extraction of bridge dynamic strain data

Baijian WU, Zhaoxia LI, Ying WANG, T. H. T. CHAN,

《结构与土木工程前沿（英文）》 2009年第3卷第4期页码 395-400 doi: 10.1007/s11709-009-0049-7

摘要： Through comparing the measured data of dynamic strains due to loading and temperature by the stain gauge and temperature sensor at the same location, the information in the strain data was divided into three parts in the frequency domain by using the defined index named power spectral density (PSD)-ratio index. The three parts are dominated respectively by temperature varying, stresses, and noises and thus can be distinguished from the determined the separatrix frequencies. Also, a simple algorithm was developed to separate the three types of information and to extract the strain caused mainly by structural stresses. As an application of the proposed method, the effect of strain deformation and noises on the fatigue assessment was investigated based on the separated data. The results show that, the determined values of separatrix frequencies are valuable for the monitoring data from other bridges. The algorithm is a multiresolution and hierarchical method, which has been validated as a simple and effective method for data analyses, and is suitable for the compression and preprocessing of the great amount monitoring data and easy to be integrated into the structural health monitoring (SHM) soft system. The strain due to temperature varying attributes a little to the errors of fatigue assessment; however, the noises or random disturbance existed in the monitoring data have much responsibility for the errors, and the main reason is that the random disturbance shifts the real strain/stress amplitude picked up by real structural stress or strain.

关键词： dynamic valuable separatrix strain/stress amplitude frequency

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变幅载荷下纤维金属层板的疲劳与寿命预测

吴学仁,郭亚军

《中国工程科学》 1999年第1卷第3期页码 35-40

摘要：

文章建立了纤维金属层板等幅疲劳载荷下的疲劳裂纹扩展速率与寿命预测模型。在此基础上对玻璃纤维-铝合金层板（GLARE）的疲劳裂纹扩展与分层扩展行为进行了试验研究，探讨了层板过载疲劳行为的机理，提出了纤维金属层板变幅载荷下疲劳寿命预测的等效裂纹闭合模型，并在GLARE层板上得到了验证。

关键词：纤维金属层板疲劳桥接分层寿命预测

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Development of electrorheological chip and conducting polymer-based sensor

Xianzhou ZHANG, Weihua LI, Weijia WEN, Yanzhe WU, Gordon WALLACE,

《机械工程前沿（英文）》 2009年第4卷第4期页码 393-396 doi: 10.1007/s11465-009-0043-8

摘要： This paper presents the development of an integrated sensor using two types of smart materials: electrorheological (ER) fluids and conducting polymers (CPs). The developed ER chip worked as an actuator, and it was driven by different voltages and control frequencies. When the four electrodes are controlled synchronously, the diaphragm acts as a vibrator whose frequency can be adjusted in accordance with the frequency of the electrical signals. The response signals of the CP sensor were recorded, and its properties were analyzed. Experimental results show that the amplitude decreases monotonically when the frequency increases, owing to the time delay in the pressure buildup in the ER chip. However, the displacement fluctuation of the diaphragm below 20Hz can be detected clearly even if the value is very low. When the vibration frequency is larger than 20Hz, the CP sensor can hardly detect the displacement fluctuation. Thus, the upper limit frequency that the CP sensor can detect is about 20Hz. The practical applications of this microdevice are also discussed.

关键词： electrorheological (ER) fluids conducting polymer (CP) polydimethylsioxane (PDMS) driving frequency amplitude bubble counter

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Impact drive rotary precision actuator with piezoelectric bimorphs

ZHANG Hongzhuang, ZENG Ping, HUA Shunming, CHENG Guangming, YANG Zhigang

《机械工程前沿（英文）》 2008年第3卷第1期页码 71-75 doi: 10.1007/s11465-008-0008-3

摘要： An impact drive rotary precision actuator with end-loaded piezoelectric cantilever bimorphs is proposed. According to finite element analysis and experiments of the dynamic characteristics of end-loaded piezoelectric cantilever bimorphs, a specific fixed-frequency and adjustable-amplitude is confirmed to control the actuator. The results show that an actuator excited by fixed-frequency and the adjustable-amplitude ramp voltage waveform works with a large travel range (180°), high resolution (1 ?rad), speed (0.2 rad/min) and heavy-load ability (0.02 Nm). With advantages of high-precision positioning ability, simple structure and only one percent the cost of traditional impact drive mechanisms, the actuator is expected to be widely used in precision industries.

关键词： specific fixed-frequency waveform piezoelectric cantilever mechanisms adjustable-amplitude

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Comparison between two commercial uranium resins and a uranyl sulphate imprinted resin based on self-assembling MIT

LIU Yaochi, XU Wei, XU Weijian, LIU Hanmao, ZHANG Xiaowen

《化学科学与工程前沿（英文）》 2007年第1卷第4期页码 327-331 doi: 10.1007/s11705-007-0059-8

摘要： In recent years, resins prepared via molecular imprinting technology have received considerable attention owing to their recognition and selective adsorption. This paper deals with the comparative investigation between a uranyl sulphate imprinted ion-exchange based on self-assembling molecular imprinting technology and two kinds of commercial uranium resins (the medium pore resin D263 and strong base resin 201×7). The studies were focused on their kinetics performance, adaptability toward pH, and performance of saturation and elution in laboratory-scale column. The results show that the imprinted ion exchange resin has the fast kinetics, high adaptability toward pH, and good adsorption and elution performance.

关键词： saturation molecular imprinting imprinting technology adaptability commercial