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    28 August 2020, Volume 25 Issue 4 Previous Issue    Next Issue

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    Influence of COVID-19 on Manufacturing Industry and Corresponding Countermeasures from Supply Chain Perspective
    CAI Min (蔡敏), LUO Jianwen (骆建文)
    2020, 25 (4):  409-416.  doi: 10.1007/s12204-020-2206-z
    Abstract ( 672 )   PDF (211KB) ( 15 )  
    It is critical for the recovery of manufacturing industry against COVID-19 by analyzing its impact
    from supply chain perspective and exploring corresponding countermeasures. Firstly, this paper studies the initial
    impact caused by worldwide spread of the coronavirus, such as production disruption of raw material and spare
    parts, unsatisfied market demand due to setbacks in logistics, increasing bankruptcy risk for small and mediumsized
    enterprises (SMEs), and demand fluctuation enlargement. Secondly, the aftershock of COVID-19 is analyzed.
    With the trend of regionalization and digitalization, two-step countermeasures are proposed to help the recovery
    of manufacturing industry within the pandemic and better prepare for the post-COVID-19 world from supply
    chain perspective.
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    Effect of Wall Deformation on Dewatering-Induced Ground Surface Settlement
    NAI Kimsrorng, LI Mingguang, CHEN Jinjian
    2020, 25 (4):  417-425.  doi: 10.1007/s12204-020-2207-y
    Abstract ( 447 )   PDF (460KB) ( 9 )  
     In practice, dewatering for pressure relief is commonly undertaken during ongoing excavation to secure
    bottom stability against basal upheaval. Simultaneously, through unloading, wall deflection is obviously observed.
    Noticing that both cause soil deformations, this research is to study the effect of wall deformation on dewateringinduced
    settlement. A coupled numerical analysis of finite-difference software is employed to model Shanghai
    soft soils under multi-aquifer-aquitard systems (MAASs) by analyzing the results in association with an empirical
    approach. Consequently, through gradual force reduction, shear strength at soil-wall interface is significantly
    diminished. As wall deformation increases instantaneously upon lower loading, wall surface becomes deformedly
    bending; this condition causes the challenge to workability of shear strength. Moreover, wall deformation caused
    by unloading affects dewatering-induced settlement substantially. Under smaller loading, large wall deflection
    is observed; soil plane of failure caused by both sliding and compression occurs along slip curve, with weaker
    shear-strength soils at rD = 0.4 and stronger shear-strength soils between rD = 0.4 and rD = 0.65, where rD is the
    distance from the wall that is normalized by the depth measured from ground surface. During dewatering, stronger
    soils tend to drag weaker soils upward to reduce large differential settlements caused by additional compression.
    Consequently, settlement becomes larger at rD = 0.4 and smaller at rD = 0.65. Remarkably, at rD > 2.3,
    both settlement curves that result from numerical analysis and empirical method show overlapping; this indicates
    that the unloading effect on dewatering-induced settlement at rD > 2.3 is insignificant. Furthermore, as wall
    reaches maximum allowable wall deflection by 67% applied force, additional compression caused by dewatering
    after loading remains smaller than that under 70% applied force, contributing to smaller dewatering-induced
    settlement.
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    How to Calculate Stormwater Management and Storage Capacity for Urban Green Space: Multidisciplinary Methods Used in Shanghai City
    YU Bingqin, GUO Jiankang, TIAN Shu, CHEN Yan, Lü Yongpeng, MO Zulan
    2020, 25 (4):  426-433.  doi: 10.1007/s12204-020-2189-9
    Abstract ( 411 )   PDF (3354KB) ( 8 )  
     In order to relieve urban environmental problems due to stormwater runoff, approaches involving the
    planning of green space for sponge city construction were previously proposed. In this study, water retention
    characteristics of 168 green spaces are surveyed to develop estimates of stormwater retention in Shanghai City’s
    center, suburbs and outskirts. Multidisciplinary methods of community investigation, soil tests, artificial rainfall
    simulation experiments, and simulations in Autodesk storm and sanitary analysis (SSA) and storm water management
    model (SWMM) are used. The factors affecting the capacity of stormwater management are identified
    and used to calculate storage estimates. The relationships among rainfall interception capacity (RIC), runoff,
    soil water storage properties, and vegetative cover are analyzed, which can provide the theoretical foundation for
    the assessment of the water-holding capacity in urban green spaces. A criterion for the selection of low impact
    development (LID) techniques for the Shanghai area is developed on the basis of the data from this study.
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    Adaptive Dual Wavelet Threshold Denoising Function Combined with Allan Variance for Tuning FOG-SINS Filter
    BESSAAD Nassim, BAO Qilian, SUN Shuodong, DU Yuding, LIU Lin, HASSAN Mahmood Ul
    2020, 25 (4):  434-440.  doi: 10.1007/s12204-020-2208-x
    Abstract ( 376 )   PDF (950KB) ( 11 )  
     Allan variance (AV) stochastic process identification method for inertial sensors has successfully combined
    the wavelet transform denoising scheme. However, the latter usually employs a traditional hard threshold
    or soft threshold that presents some mathematical problems. An adaptive dual threshold for discrete wavelet
    transform (DWT) denoising function overcomes the disadvantages of traditional approaches. Assume that two
    thresholds for noise and signal and special fuzzy evaluation function for the signal with range between the two
    thresholds assure continuity and overcome previous difficulties. On the basis of AV, an application for strap-down
    inertial navigation system (SINS) stochastic model extraction assures more efficient tuning of the augmented 21-
    state improved exact modeling Kalman filter (IEMKF) states. The experimental results show that the proposed
    algorithm is superior in denoising performance. Furthermore, the improved filter estimation of navigation solution
    is better than that of conventional Kalman filter (CKF).
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    Active Disturbance Rejection Controller Based Heading Control of Underwater Flight Vehicles
    ZHENG Tianhai, FENG Zhengping, ZHAO Shuo, PAN Wanjun
    2020, 25 (4):  441-446.  doi: 10.1007/s12204-020-2194-z
    Abstract ( 378 )   PDF (2251KB) ( 17 )  
    The total disturbance estimated by the extended state observer (ESO) in active disturbance rejection
    controller (ADRC) is affected greatly by measurement noise when the control step is small in heading control
    of underwater flight vehicles (UFVs). In order to prevent rudder from high-frequency chattering caused by
    measurement noise, a tracking-differentiator (TD) is integrated to the ESO to develop an improved ADRC scheme.
    The improved ADRC suppresses the impact of sensor noise. Both the results of simulations and tank tests show
    the effectiveness of improved ADRC based heading control.
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    Intrafascicular Vagal Activity Recording and Analysis Based on Carbon Nanotube Yarn Electrodes
    ARRANZ Javier, GUO Jinyao, YU Xiao, WANG Jiaojiao, CHAI Xinyu, WANG Jiguang, SUI Xiaohong
    2020, 25 (4):  447-452.  doi: 10.1007/s12204-020-2197-9
    Abstract ( 307 )   PDF (2418KB) ( 11 )  
    The vagus nerve carries sensory information from multiple organs in the body. The recording of
    its activity and further processing is a key step for neuromodulation treatments. This paper presents a specific
    algorithm for the processing and discrimination of intrafascicular recordings from the vagus nerve using the
    novel carbon nanotube yarn electrodes. Up to four different neural waveforms were found, whose occurrence
    corresponded to distinct levels of anesthesia depth.
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    Data-Driven Predictive Maintenance Approach for Spinning Cyber-Physical Production System
    FAROOQ Basit, BAO Jinsong, LI Jie, LIU Tianyuan, YIN Shiyong
    2020, 25 (4):  453-462.  doi: 10.1007/s12204-020-2178-z
    Abstract ( 295 )   PDF (1444KB) ( 8 )  
    The fundamental process of predictive maintenance is prognostics and health management, and it
    is the tool resulting in the development of many algorithms to predict the remaining useful life of industrial
    equipment. A new data-driven predictive maintenance and an architectural impulse, based on a regularized deep
    neural network using predictive analytics, are proposed successfully for ring spinning technology. The paradigm
    shift in computational infrastructures enormously puts pressure on large-scale linear and non-linear automated
    assembly systems to eliminate and cut down unscheduled downtime and unexpected stoppages. The sensor
    network designed for the scheduling process comprises different critical components of the same spinning machine
    frames containing more than thousands of spindles attached to them. We established a genetic algorithm based
    on multi-sensor performance assessment and prediction procedure for the spinning system. Results show that it
    operates with a relatively less amount of training data sets but takes advantage of larger volumes of data. This
    integrated system aims to prognosticate abnormalities, disturbances, and failures by providing condition-based
    monitoring for each component, which makes it more accurate to locate the defined component failures in the
    current spinning spindles by using smart agents during the operations through the neural sensing network. A case
    study has provided to demonstrate the feasibility of the proposed predictive model for highly dynamic, high-speed
    textile spinning system through real-time data sensing and signal processing via the industrial Internet of Things.
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    Coupling Mathematical Model of Marine Propulsion Shafting in Steady Operating State
    WEN Xiaofei, ZHOU Ruiping, YUAN Qiang, LEI Junsong
    2020, 25 (4):  463-469.  doi: 10.1007/s12204-020-2192-1
    Abstract ( 399 )   PDF (464KB) ( 9 )  
    According to the analysis of the problems about the operation of marine propulsion shafting in steady
    state, the geometric and mechanical coupling relationships between marine propulsion shafting and oil film of
    bearings in two-dimensional space are established, and a coupling mathematical model of the marine propulsion
    shafting in steady operating state is proposed. Then the simulation of a real ship is carried out, and the variation
    laws of some special parameters such as bearing load and deflection are obtained. Finally, the results of simulation
    are verified by experimental data of a real ship, which can provide the mathematical model and analysis method
    for the research on the characteristics of ship propulsion shafting condition in steady state.
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    Three-Dimensional Trajectory Tracking Control of Underactuated Autonomous Underwater Vehicles with Input Saturation
    HUANG Hantao, ZHOU Jingye, DI Qing, ZHOU Jiawei , LI Jiawang
    2020, 25 (4):  470-477.  doi: 10.1007/s12204-020-2195-y
    Abstract ( 435 )   PDF (310KB) ( 10 )  
    This paper addresses a three-dimensional (3D) trajectory tracking problem of underactuated autonomous
    underwater vehicles (AUVs) subjected to input saturation and external disturbances. The proposed
    controller can achieve practical convergence of tracking errors for general reference trajectories, including persistently
    exciting (PE) time varying trajectories and fixed points. At first, a modified error state formulation
    is introduced to tackle the situation that desired velocities do not satisfy PE condition. Then, on the basis of
    the backstepping technique and a Nussbaum-type even function, a saturated controller is designed so that the
    tracking errors can converge to a bounded neighborhood of the origin. The stability analysis based on Lyapunov
    theory shows that the tracking errors are globally ultimately uniformly bounded. Finally, some simulation results
    illustrate the effectiveness and robustness of the proposed control strategy.
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    Sliding Mode Control of T-Shaped Pedestrian Channel
    CHANG Lu, SHAN Liang, LI Jun, DAI Yuewei
    2020, 25 (4):  478-485.  doi: 10.1007/s12204-020-2198-8
    Abstract ( 351 )   PDF (776KB) ( 8 )  
    The study of pedestrian evacuation in channels with different structures is important among optimizing
    through efficiency, avoiding accidents and designing passageway. It is of significant reference to set up a specific
    model on account of the real traffic system and design an appropriate controller to apply on it. This paper
    establishes a macroscopic model for T-shaped channel with a number of controlled entrances basing on the law
    of mass conservation. Then, with the method of cascade, a kind of sliding mode controller is designed to achieve
    the control target of avoiding the blocking and maximizing the pedestrian flow of the whole model, the stability
    of the system is proved by the Lyapunov stability theory, and the boundary layer method is applied to restrain
    the chattering of the controller. Finally, simulation results show the efficiency of the sliding mode controller and
    the improvement brought by the boundary layer method.
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    Supporting Earth Pressures for Foundation Excavation Considering Suction Stress of Soil
    LI Jingpei, CAO Xiaobing, LI Lin
    2020, 25 (4):  486-494.  doi: 10.1007/s12204-020-2187-y
    Abstract ( 348 )   PDF (379KB) ( 9 )  
    The infiltration, evaporation and variation of the groundwater table have significant effects on the
    suction stress of the soils and the supporting earth pressures of the foundation excavation. The distribution
    of the suction stresses above the ground water table is derived under different fluxes at the ground surface,
    according to the soil-water characteristic parameters and the effective degree of saturation. In consideration of
    the cohesive stress formed from the soil suction stress and the relevant anti sliding effect, the calculation model
    of supporting earth pressures for foundation excavation is established by the variational limit equilibrium method
    under the steady flow condition. The evolution of the supporting earth pressures is studied in detail for foundation
    excavation under different fluxes at the ground surface. The effects of the soil-water characteristic parameters, the
    ground water table and the internal friction angle on the supporting earth pressures are discussed. The results
    show that the suction stress is reduced because of the infiltration, and thus the supporting earth pressure increases.
    The larger the air-entry pressures and the pore size are, the smaller the supporting earth pressures are. The higher
    the ground water table is, the larger the supporting earth pressures are. In order to reduce the construction risk,
    the effects of the suction stress and the evolution of the potential critical sliding surface should be considered
    during the calculation of the supporting earth pressures.
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    Collapse Patterns and Their Discrimination of Reinforced Concrete Shear Wall Under Combined Stresses of Compression and Shear due to Strong Earthquake
    ZHA Zhixiang, LIU Xila, XU Bo
    2020, 25 (4):  495-508.  doi: 10.1007/s12204-020-2175-2
    Abstract ( 266 )   PDF (3526KB) ( 8 )  
    The collapse patterns of reinforced concrete (RC) shear walls under seismic load are proposed. The
    crack distribution and propagation of shear walls are specifically based on the failure criterions of Mohr-Coulomb
    with tension cutoff. Three zones and five different corresponding failure modes of RC shear walls are determined
    according to the transfer path of shear stress in shear wall. These failure modes of shear walls under seismic load
    are verified by many experimental results and can be utilized in collapsing analysis for frame-shear wall structure.
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    Vibration of Axle Box from Wheel Diameter Difference in Vehicle
    CHENG Daolai, XU Lei, SUN Xiaojie
    2020, 25 (4):  509-518.  doi: 10.1007/s12204-020-2180-5
    Abstract ( 381 )   PDF (1006KB) ( 11 )  
    The wheel diameter difference would worsen the dynamic performance and affect the safety of the
    rail vehicle. Therefore, it is necessary to detect wheel diameter difference while the train is operating. However,
    several existing detection methods can’t accurately detect and diagnose the wheel diameter difference under highspeed
    running environment. In this study, a new method of detecting wheel diameter difference was proposed
    for high speed rail vehicle. The wheel diameter difference would be diagnosed by the amplitude and frequency
    of vibration impact on the axle box. Firstly, the dynamic model with varying wheel diameters was established
    in SIMPACK, and LMA tread was used in high-speed rail vehicles. Then, the simulation results of rail vehicle
    dynamic performance were compared under different wheel diameter differences. After that, the relationship
    between axle box vibration and wheel diameter difference was used to demonstrate the feasibility of this detection
    technology. Finally, comparing and analyzing the simulation results of vibration obtained by matching treads
    with different wheel diameters, it shows that by increasing the wheel diameter difference, the longitudinal and
    lateral impacts on axle boxes increase asymmetrically, and the amplitude and the frequency become more evident.
    Therefore, this paper presents a technical scheme of online measuring wheel diameter difference by monitoring the
    vibration of the axle box.
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    Mechanism of MSWI Fly Ash Solidified by Microbe Cement
    RONG Hui, WEI Guanqi, QIAN Chunxiang, ZHANG Lei, ZHANG Ying, XU Rui
    2020, 25 (4):  519-525.  doi: 10.1007/s12204-020-2199-7
    Abstract ( 399 )   PDF (5919KB) ( 9 )  
    Microbe cement, a new type of gelling material, has attracted wide attention due to the increasing
    awareness of environmental protection. In this paper, the microbe cement in solidifying municipal solid waste
    incineration (MSWI) fly ash is investigated and the effect of the microbial induction method in solidifying MSWI
    fly ash is compared with the traditional chemical reaction strategy by characterizing the resulted calcite and the
    solidification productions with electronic universal testing machine, X-ray diffractometer (XRD), Fourier transform
    infrared spectrometer (FTIR), scanning electron microscope (SEM) and atomic absorption spectrometer. The
    results show that the MSWI fly ash solidified by microbe cement has the highest compressive strength while that
    of the chemical CaCO3 products is the lowest. The XRD results show that a new hydration gelling substance
    (Ca2SiO4·0.30H2O) is generated in the MSWI fly ash products. The FTIR results show that the frequency of
    Si—O bonds and C—O bonds in the products solidified by microbe cement has shifted, while there is no change
    occurred in the chemical CaCO3 products. The SEM results show that the microstructure of the products solidified
    by microbe cement is denser than that of chemical CaCO3 products. The test results of heavy metals show that
    the microbe cement could reduce the leaching concentration of heavy metals in MSWI fly ash. Ultimately, the
    leaching concentration of Pb meets the standard requirements, while that of Cd is still slightly higher than the
    standard requirement.
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    Fatigue Life Prediction for Flange Connecting Bolts of Wind Turbine Tower
    YU Zelin, SUN Pengwen, WANG Dong
    2020, 25 (4):  526-530.  doi: 10.1007/s12204-020-2173-4
    Abstract ( 444 )   PDF (1312KB) ( 9 )  
    Flange joint part is the weak link of wind turbine tower. In view of the special structure, complex stress
    and easy failure of the connecting bolt of the wind turbine tower flange, the relationship between the external
    load of the tower section and the internal stress of the bolt is established by the finite element method, and the
    time series internal stress of the bolt is calculated by the Schmidt-Neuper algorithm. The S-N curve which is
    suitable for the connecting bolt material of the tower flange is selected by the GL2010 specification. On the basis
    of Miner’s fatigue cumulative damage theory and rain flow counting method, the fatigue strength of the whole
    ring bolt is roughly calculated, and the most dangerous part is determined. The axial symmetry model of screw
    connection is used for accurately calculating the fatigue cumulative damage of the bolt at the dangerous part.
    The results show that the fatigue life of the bolts in the most dangerous position can meet the requirements, the
    engineering algorithm has advantages in determining the dangerous part of the whole ring bolt, and the finite
    element method has high accuracy in predicting the fatigue life of the bolts in the dangerous part. The proposed
    method is feasible and effective in predicting the fatigue life of the flange joint bolts of the tower.
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    Leakage Model of Axial Clearance and Test of Scroll Compressors
    WANG Jianji, LIU Tao
    2020, 25 (4):  531-537.  doi: 10.1007/s12204-020-2163-6
    Abstract ( 314 )   PDF (8187KB) ( 13 )  
     Leakage clearance plays an important role in guaranteeing high efficiency of scroll compressors. In view
    of the shortcomings of the existing leakage models of axial clearance of scroll compressors, a modified Fano flow
    model and a turbulence model are presented based on the flow characteristics of fluid in the leakage passage under
    actual working conditions. Firstly, according to the Fano flow energy equation and the turbulence theory, two kinds
    of leakage models, Fano flow model and turbulence model, of axial clearance are established. Then, the established
    models are verified through an experimental platform established to measure the axial clearance leakage in the
    working process of a scroll compressor, and the measured values are compared with the values obtained from the
    two theoretical models. Finally, the effect of such factors as pressure difference, clearance amount, spindle speed
    on the axial clearance leakage is analyzed. Results show that the two established models can precisely reflect the
    variation law of axial clearance leakage of scroll compressor under different working conditions. In particular, the
    Fano flow model is more suitable for predicting the clearance leakage when the spindle speed is low (less than
    3 500 r/min) and the clearance is small (less than 0.025 mm), whereas the turbulence model is suitable for high
    spindle speed (more than 3 500 r/min) and large clearance (more than 0.025 mm).
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    Multi-Objective Structural Optimization of a Wind Turbine Tower
    ZHENG Yuqiao, ZHANG Lu, PAN Yongxiang, HE Zhe
    2020, 25 (4):  538-544.  doi: 10.1007/s12204-020-2190-3
    Abstract ( 421 )   PDF (342KB) ( 9 )  
    The 2MW wind turbine tower is considered as the baseline configuration for structural optimization.
    The design variables consist of the thickness and height located at the top tower junction. The relationships
    between the design variables and the optimization objectives (mass, equivalent stress, top displacement and
    fatigue life) are mapped on the basis of uniform design and regression analysis. Subsequently, five solutions are
    developed by an algorithm, NSGA-III. According to their efficiency and applicability, the most suitable solution
    is found. This approach yields a decrease of 0.48% in the mass, a decrease of 54.48% in the equivalent stress and
    an increase of 8.14% in fatigue life, as compared with existing tower designs. An improved wind turbine tower is
    obtained for this practice.
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