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Table of Content

    28 July 2022, Volume 56 Issue 7 Previous Issue    Next Issue
    New Type Power System and the Integrated Energy
    A Shared Energy Storage Optimal Operation Method Considering the Risk of Probabilistic Voltage Unbalance Factor Limit Violation
    FANG Xiaotao, YAN Zheng, WANG Han, XU Xiaoyuan, CHEN Yue
    2022, 56 (7):  827-839.  doi: 10.16183/j.cnki.jsjtu.2021.455
    Abstract ( 934 )   HTML ( 605 )   PDF (1838KB) ( 651 )   Save

    The distributed access with single-phase and uncertain generation of the renewable energy increase the risk of voltage unbalance limit violation in the distribution network. With the increasing penetration rate of the renewable energy generation, it is important to study the mitigation of the impacts of intermittent renewable energy generation on the risk of voltage unbalance limit violation in the distribution network. A shared energy storage allocation strategy and optimal operation method based on global sensitivity analysis (GSA) is proposed. First, a back propagation neural network (BPNN) based probabilistic voltage unbalance factor calculation model for the distribution network is constructed, and the risk index of the distribution network probabilistic voltage unbalance factor limit violation is defined, which can quickly and accurately quantify the impact of uncertain renewable energy generation on the risk of voltage unbalance limit violation in the distribution network. Then, a GSA method based on Wasserstein distance is proposed to identify the critical renewable energy sources affecting the distribution network voltage unbalance. Finally, the GSA-based shared energy storage allocation strategy and the rolling prediction optimization-based operation method of the shared energy storage are proposed. The effectiveness of the proposed method is verified through the simulation analysis of IEEE 123-bus distribution network.

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    Electronic Information and Electrical Engineering
    Intelligent Global Sensitivity Analysis Based on Deep Learning
    WU Shuchen, QI Zongfeng, LI Jianxun
    2022, 56 (7):  840-849.  doi: 10.16183/j.cnki.jsjtu.2021.191
    Abstract ( 1019 )   HTML ( 49 )   PDF (1418KB) ( 829 )   Save

    This paper proposes an end-to-end method that combines deep learning and sensitivity analysis, which can perform gradient back propagation calculation sensitivity on the saved weight information while training the model. The structure and activation function of the depth model are specially designed to adapt to the subsequent sensitivity calculation. The experimental results conducted on a Boston house prices dataset, a track information fusion dataset, and the G function show that the proposed method is more accurate than classical methods such as Sobol’ method when the parameter distribution is uneven, and has a stronger robustness. Compared with the traditional neural network method, the accuracy of the proposed method is higher. The experiment proves that the sample parameter sensitivity obtained by the deep learning model can be used to optimize the model output.

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    An Image Self-Calibration Method Based on Parallel Laser Ranging
    CHENG Bin, HUANG Bin, LI Derui
    2022, 56 (7):  850-857.  doi: 10.16183/j.cnki.jsjtu.2021.447
    Abstract ( 765 )   HTML ( 22 )   PDF (3660KB) ( 648 )   Save

    Regarding the disadvantages of existing camera calibration methods, such as external information relative, special camera poses,the need for calibration targets, and complex operations, this paper proposes a real-time self-calibration method based on parallel laser ranging by employing high-precision laser rangefinders to synchronously measure the position of the measured object plane when taking pictures, so that the object plane equation can be solved. The 2D coordinates of at least four sets of corresponding points on object plane and image planes are selected to obtain the homography matrix, which represents the mapping relationship between object and image planes, so as to complete the calibration simply and quickly. A calibration device is developed to validate the accuracy of the proposed self-calibration method in different testing scenarios. The results show that the measurement error of line segments length in the image are between -0.49% and 0.15%, and the average errors are merely -0.14%, which indicates that the parallel laser ranging self-calibration method proposed in this paper is accurate and robust. The causes of measurement error are further investigated by analyzing the influences of laser ranging, laser inclination, and device offset. The error eliminating suggestions are provided to give references for the application of the proposed self-calibration method in the field of image measurement.

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    Path Optimization of Stacker in Compact Storage System with Dual-Port Layout
    YAN Qing, LU Jiansha, JIANG Weiguang, SHAO Yiping, TANG Hongtao, LI Yingde
    2022, 56 (7):  858-867.  doi: 10.16183/j.cnki.jsjtu.2021.283
    Abstract ( 690 )   HTML ( 18 )   PDF (2434KB) ( 485 )   Save

    The compact storage system is a new storage technology in the field of intelligent logistics technology, and its most typical feature is that it can realize multi-depth storage of unit loads. In this paper, the path optimization problem of the co-existence of both single command (SC) and dual command (DC) operations of the stacker in the dual-port layout is studied, and the mathematical model of the problem is established with the shortest travel time of the stacker as the objective. A genetic algorithm (GA)-beam search (BS) hybrid optimization algorithm is designed to solve the model, and the optimal individual obtained by the GA is used as the initial path choice of the BS to avoid local optimum. The effectiveness of the model and algorithm is verified by numerical simulation, and the results show that the operation path optimization model of the stacker and the designed solution method can better adapt to the I/O tasks scheduling requirements in the compact three-dimensional warehouse with dual-port layout, get a more reasonable stacker scheduling scheme, and improve the storage efficiency.

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    Disturbance-Blocking-Based Distributed Receding Horizon Estimation of Flexible Joint Robots
    XU Chenhui, YU Fanghui, HE Defeng
    2022, 56 (7):  868-876.  doi: 10.16183/j.cnki.jsjtu.2021.186
    Abstract ( 560 )   HTML ( 25 )   PDF (1332KB) ( 381 )   Save

    Considering the state monitoring problem of flexible joint robots (FJRs) caused by the easy deformation in practice, a distributed receding horizon estimation algorithm based on disturbance blocks is proposed. Based on distributed consistent receding horizon estimation, the proposed algorithm reduces the computational amount and achieves rapidity by designing the disturbance block and applying it to the process disturbance sequence in the estimation window to reduce the variables related to optimization. By analyzing the feasibility and convergence of the proposed algorithm based on the maximum block length, the assumptions are made under which the existence of equivalent solution to the optimization problem of the algorithm is guaranteed, and the results are extended to the case that the process disturbance can be divided into arbitrary blocks. The simulation results show that the proposed algorithm can effectively shorten the computation time without affecting the estimation error compared with the algorithm without disturbance blocks.

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    Radar Signal Recognition Based on Dual Channel Convolutional Neural Network
    QUAN Daying, CHEN Yun, TANG Zeyu, LI Shitong, WANG Xiaofeng, JIN Xiaoping
    2022, 56 (7):  877-885.  doi: 10.16183/j.cnki.jsjtu.2021.209
    Abstract ( 895 )   HTML ( 28 )   PDF (4098KB) ( 760 )   Save

    In order to solve the problems of difficult feature extraction and low recognition rate of radar signal at low signal-to-noise ratios, a dual channel convolutional neural network model based on Choi-Williams distribution (CWD) and multisynchrosqueezing transform (MSST) is proposed, which obtains two-dimensional time-frequency images by CWD and MSST time-frequency analyses on radar signals. Respectively, the time-frequency images are preprocessed and sequencely fed to a dual channel convolutional neural network for deep feature extraction. Finally, the features acquired by the two channels are fused, and the radar signal is classified and recognized through the convolutional neural network classifier. The simulation results show that when the signal-to-noise ratio is -10 dB, the overall recognition accuracy can reach above 96%, which is excellent at low signal-to-noise ratios.

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    Transportation Engineering
    Centrifugal Test and Numerical Analysis of Impact of Surface Surcharge on Existing Tunnels
    LIU Jinhao, YAN Yuanzhong, ZHANG Qi, BIAN Rong, HE Lei, YE Guanlin
    2022, 56 (7):  886-896.  doi: 10.16183/j.cnki.jsjtu.2020.412
    Abstract ( 621 )   HTML ( 16 )   PDF (14733KB) ( 591 )   Save

    Surface surcharge has a significant impact on the safety and stability of existing underground tunnels, and relevant regulations in soft clay areas have very strict restrictions on the tunnel displacement caused by surface surcharge. In order to accurately assess the impact of surface surcharge on the tunnel displacement in soft clay areas, the influence of surface surcharge on tunnel displacement and soil deformation is studied by using the centrifugal model test, and a corresponding finite element model is established based on the centrifugal model test. The parameter values of the soil constitutive model are determined by indoor soil tests. From the aspects of soil strain and shear stiffness, the applicability of the HS model and the HSS model in the analysis of the soft clay surface surcharge problem is compared and analyzed. Based on the result, the influence of surface surcharge on the deformation of soft clay formation and tunnel displacement is further discussed while comprehensively considering the size of the surface surcharge and the location of the tunnel. The results can provide some reference for engineering design.

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    Development and Application of a Model Test Platform of Synchronous Technology Combining Shield Tunneling with Segment Assembling
    ZHU Yeting, MIN Rui, QIN Yuan, WU Wenfei, YUAN Peng, ZHAI Yixin, ZHU Yanfei
    2022, 56 (7):  897-907.  doi: 10.16183/j.cnki.jsjtu.2021.241
    Abstract ( 634 )   HTML ( 13 )   PDF (19372KB) ( 447 )   Save

    Taking a running tunnel of Shanghai Railway Airport connecting line as a demonstration application project, the synchronous technology combining shield tunneling with segment assembling is proposed based on the active control on the oil pressure of the shield thrust system, which can solve the problem of the long construction period produced by a single shield machine employed in a long-distance shield tunnel project. The principle is to make full use of the extra stroke of propulsion cylinders generated by the axial insertion of the key block to assemble segments, and the theoretical operation time of a single ring can be reduced by 31.6%. Then, a large model test platform for this synchronization technology is established to verify its feasibility and reliability, and the redistribution method of the missing thrust force is introduced during the synchronous process, which is verified by the model test. The test results show that the actuators of the shield machine respond quickly, and the errors of the cylinder pressures and total thrust force of the propulsion system are controlled within ±2%. The attitude deviation of the shield machine is controlled within ±6 mm, and the error range of the driving speed is -2 to 4 mm/min. The segments are safe with the designed overburden thickness of 33 m, and the compressive safety coefficient reaches 1.68.

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    Dynamic Responses Law of Subgrade of a Special Railway Line in Loess Region
    WANG Rui, HU Zhiping, YIN Ke, MA Jiakuan, REN Xiang
    2022, 56 (7):  908-918.  doi: 10.16183/j.cnki.jsjtu.2021.130
    Abstract ( 710 )   HTML ( 17 )   PDF (4239KB) ( 423 )   Save

    In order to investigate the dynamic response law of subgrade of a special railway line in loess region under moving train loading, the field test data and 2.5D finite element results were adopted to assess the dynamic stress distribution and its influence depth, and the environmental vibration law in the office area along the line was also analyzed. The results show that the excessive abstraction of the track system might enlarge the amplitude and influence the range of dynamic stress. The entity modeling of the ‘ballast-sleeper-fastener’ system makes the distribution of the dynamic stress in the subgrade more reasonable. The influence of energy consumption caused by the dynamic creep of soil have a negligible influence when the subgrade is in a quasi-static state. The speed has a negligible effect on the distribution of the dynamic stress of the subgrade when a freight train is running at a low speed, and the influence depth of the dynamic stress is about 4.2 m. As the speed decreases, the influence of track irregularity on the environmental vibration increases. The environmental vibration can be effectively controlled by improving the short wave length irregularity.

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    A Numerical Study of Hydrodynamic Interactions Between a Large Cruise Ship and a Container Ship
    SONG Shenke, XIA Li, ZOU Zaojian, ZOU Lu
    2022, 56 (7):  919-928.  doi: 10.16183/j.cnki.jsjtu.2021.257
    Abstract ( 713 )   HTML ( 18 )   PDF (3495KB) ( 421 )   Save

    The large cruise ship is a type of ship with large size and high added value, which has been increasingly studied and developed during the recent years. Since a large cruise ship often sails in the crowded waters such as harbor and coastal area, the study of the hydrodynamic interaction between the cruise ship and other ships is crucial to ensure the navigation safety. Taking a large cruise ship and a KCS container ship as the study object, the hydrodynamic characteristics of the two ships at different longitudinal positions, transverse positions, and ship speeds in both deep and shallow water are predicted in model scale by solving the unsteady Reynolds-averaged Navier-Stokes (RANS) equations, and the variations of the hydrodynamic interactions between the two ships are identified. It is shown that different relative positions and ship speeds have significant effects on the lateral force and yaw moment acting on the two ships. The hydrodynamic interaction between the two ships in shallow water is more remarkable, and the relatively smaller ship is more affected by the ship-to-ship interaction.

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    Ultimate Strength and Protective Performance of Stiffened Panels Exposed to Fire-Induced High Temperature
    YU Xinye, XUE Hongxiang, Yan Shuwei
    2022, 56 (7):  929-936.  doi: 10.16183/j.cnki.jsjtu.2021.196
    Abstract ( 665 )   HTML ( 17 )   PDF (11175KB) ( 378 )   Save

    Stiffened panel is a typical strength member in ships. Considering the change of material properties under the action of fire and high temperature, according to the thermal elastic-plastic finite element theory, based on the nominal temperature-time curve, the protective effect of the passive fire protection layer on the high temperature response characteristics and the residual strength of the stiffened panel and the influence of coating positions on the failure mode of the stiffened panel are studied, which provides reference for structural performance evaluation and structural fire protection design. Numerical analyses indicate that passive fire protection layer can effectively slow down the increase of stress and deformation induced by temperature rise. Overall coating does not change the failure mode of the overall buckling of the structure accompanied by the tripping of the stiffener, but significantly delays the failure time and has an obvious effect on maintaining residual ultimate strength. Partial coating will change the failure characteristics of the structure. Overall failure occurs when only the plate is coated, and beam-column failure occurs when only the stiffener is coated, accompanied by local buckling of the web. Overall coating shows the best protective performance on the residual strength of the stiffened panel, followed by plate coating. Stiffener coating, however, has a weak protective effect. The protection performance mainly depends on the heating and failure mode of the structure.

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    Application of Adaptive Sampling Method in Hull Form Optimization
    OUYANG Xuyu, CHANG Haichao, LIU Zuyuan, FENG Baiwei, ZHAN Chengsheng, CHENG Xide
    2022, 56 (7):  937-943.  doi: 10.16183/j.cnki.jsjtu.2021.179
    Abstract ( 672 )   HTML ( 15 )   PDF (6308KB) ( 493 )   Save

    In order to handle the problem of complex and time-consuming simulation calculation in hull form optimization, the approximate model based on adaptive sampling has been widely used. In this paper, a maximum entropy (ME) adaptive sampling method based on uniform design (UD) is developed based on the Kriging approximate model and the leave-one-out (LOO) error method. Compared with the incremental Latin hypercube design (LHD) method, the adaptive sample distribution obtained by the proposed method are more uniform, and the accuracy of the global approximation model is higher. The proposed method is applied to the S60 hull form optimization, and the effectiveness is verified.

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    Robust Seabed Terrain Following Control of Underactuated AUV with Prescribed Performance Guidance Law Under Time Delay of Actuator
    LI Jinjiang, XIANG Xianbo, LIU Chuan, YANG Shaolong
    2022, 56 (7):  944-952.  doi: 10.16183/j.cnki.jsjtu.2021.375
    Abstract ( 760 )   HTML ( 16 )   PDF (1420KB) ( 426 )   Save

    To address the uneven seabed following control problem under the time delay constraint of the actuator for the autonomous underwater vehicle (AUV), a robust time-delay controller with prescribed performance guidance law is proposed in this paper, which can improve the safety of the AUV during navigation. First, the seabed following error conversion is firstly performed based on a navigational safety barrier function. Then, by integrating the time-varying line-of-sight guidance angle, the prescribed performance guidance law is designed at the kinematics level to provide reference state input for the AUV. After that, to tackle the time delay problem of actuators and reduce demand for accurate modeling, a robust time-delay dynamic controller is designed using the radial basis function (RBF) neural network. Finally, based on the Lyapunov theory, the stability of the closed-loop system is proved. The simulation results illustrate that the designed controller can achieve uneven seabed following control. Moreover, the following errors are always confined to the preset limits, which can also enhance the safety performance of the AUV when following the uneven terrain of the seabed.

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    A Joint Optimization of Vessel Scheduling and Refueling Strategy for Container Liner Shipping with Cooperative Agreements
    LI Dechang, YANG Hualong, DUAN Jingru
    2022, 56 (7):  953-964.  doi: 10.16183/j.cnki.jsjtu.2021.105
    Abstract ( 687 )   HTML ( 12 )   PDF (1251KB) ( 391 )   Save

    This paper studies the joint optimization problem of vessel scheduling and refueling strategy for container liner shipping with cooperative agreements signed by the container terminal operators and the shipping company with multiple vessel arrival time windows, multiple start and end times, and multiple handling rates. A non-linear mixed integer programming model for vessel scheduling and refueling strategy problem of liner shipping is established considering fuel price difference and discount factors at different refueling ports, which aims to minimize the total cost of liner shipping service. A set of discretization and linearization technique is applied to the original model in accordance with the vessel navigation controlling practice. Taking the AEX1 route served by China COSCO Shipping Corporation Limited as an example, a large number of simulation verifications are conducted. The results of numerical examples show that the joint optimization of vessel scheduling and refueling strategy helps shipping companies to flexibly adjust vessel sailing speed. It can significantly reduce the total cost of liner shipping service. The sensitivity analysis indicates that the total cost of liner shipping service and the vessel refueling volume in a voyage will reduce with the expansion of time window of vessel arrival at port in the cooperative agreement. No matter how the fuel price changes, the joint optimization of vessel scheduling and refueling strategy can effectively reduce the total cost of liner shipping service.

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    Method of Curing Deformation Prediction and Surface Reconstruction Compensation for Roller-Hemming Structures with Dissimilar Materials
    LI Jianjun, ZHU Wenfeng, SUN Haitao, LI Yuanhui, WANG Shunchao
    2022, 56 (7):  965-976.  doi: 10.16183/j.cnki.jsjtu.2021.225
    Abstract ( 639 )   HTML ( 18 )   PDF (12183KB) ( 420 )   Save

    Dissimilar material structure has the advantages of both cost and performance, and has become an important means of lightweight for the new generation of autobody closure panels. However, the difference between physical properties of sheets and the complex change of adhesive material properties are easy to lead to structural curing mismatch deformation. In order to eliminate the structure deformation, a method for deformation prediction and surface reconstruction pre-compensation was proposed. Then, considering the material property transformation effect of curing degree, chemical shrinkage, and stress relaxation, a thermal-chemical-structural field coupled model for high temperature curing of hemming adhesive was established. Taking the typical aluminum/steel sheet curved-edge hemming structure as the research object, the multi-physics field curing process was simulated and analyzed, and the deformation of aluminum alloy outer panel was predicted, which was verified by non-contact measurement experiment using digital image correlation (DIC) method. Finally, the geometric compensation of curing deformation was conducted, the compensation efficiency of constraint direction, connection direction, and normal direction was compared and analyzed, and the reliability of the method was verified by experiment. The results show that compared with the traditional viscoelastic model, the multi-physics field coupling model can more accurately reflect the high temperature curing deformation of hemming structures with dissimilar materials. The geometric compensation method based on non-uniform rational B-splines (NURBS) surface reconstruction can effectively reduce the curing deformation of structures, and the normal direction compensation method is more efficient. This paper provides an important reference for the improvement of manufacturing accuracy and process optimization of the new generation of autobody closure panels with dissimilar materials.

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