Loading...

Table of Content

    28 December 2020, Volume 54 Issue 12 Previous Issue    Next Issue
    A State-Integrated Approach for Generalized Functional Modeling
    ZHAO Meng, CHEN Yong, TANG Chao, LI Haomin, XIE Youbai
    2020, 54 (12):  1227-1234.  doi: 10.16183/j.cnki.jsjtu.2019.093
    Abstract ( 788 )   HTML ( 562 )   PDF (4525KB) ( 434 )   Save

    With the model-based approaches gaining popularity in the development of complex systems, formal approaches for functional modeling have attracted a lot of attention. However, existing approaches for functional modeling do not involve structural states of a system, which often makes the functional models of such systems ambiguous and incomplete. To address this issue, research on a state-integrated approach for generalized functional modeling has been conducted. First, the State-Bahvior-Function model for components is proposed, which can represent the structural states, behaviors, and functions of a component. Thereafter, an approach for generalized functional modeling of systems is proposed, which can represent different structural states of a system, as well as the functions corresponding to the states of the system. Finally, the functional modeling process of a peeler centrifuge is provided as an example, which demonstrates that the state-integrated approach for generalized functional modeling can enable engineers to establish explicit and complete functional models of systems.

    Figures and Tables | References | Related Articles | Metrics
    Joint Optimization Strategy of Predictive Maintenance and Tool Replacement for Energy Consumption Control
    SHI Guo, SI Guojin, XIA Tangbin, PAN Ershun, XI Lifeng
    2020, 54 (12):  1235-1243.  doi: 10.16183/j.cnki.jsjtu.2019.134
    Abstract ( 746 )   HTML ( 7 )   PDF (1583KB) ( 507 )   Save

    With the rise of sustainable development and energy-saving mode in the manufacturing industry, a joint optimization strategy of machine predictive maintenance and tool replacement is proposed aiming to meet the needs of energy control and maintenance decision for computer numerical control (CNC) machine and tools. The non-value-added energy consumption is taken as the research emphasis, while the phased tool wear evolution is introduced into the energy modeling of the CNC machine. First, predictive maintenance (PM) scheduling of the CNC machine based on healthy evolution aims to achieve the minimization of the non-value-added power. Secondly, based on the sequential outputs of the CNC machine PM intervals, a joint replacement model of the tool is also established considering comprehensive energy saving and economy. The optimal cycle interval of tool preventive replacement and the CNC machine PM is obtained in the joint optimization layer. The case study analysis shows that compared with the traditional maintenance strategies, this joint optimization strategy can significantly reduce the total non-value-added energy consumption.

    Figures and Tables | References | Related Articles | Metrics
    Simulation of PD Optical Signal Mechanism Based on FCT Algorithm
    ZHANG Yue, QIAN Yong, LIU Wei, ZANG Yiming, SHENG Gehao, JIANG Xiuchen
    2020, 54 (12):  1244-1251.  doi: 10.16183/j.cnki.jsjtu.2019.163
    Abstract ( 718 )   HTML ( 13 )   PDF (5199KB) ( 428 )   Save

    The flux-corrected transport (FCT) algorithm is used to simulate the two-dimensional planar needle-plate structure of the positive streamer model and the partial discharge process of tip defects. The variations in electron density, net charge density and electric field during the movement of the positive streamer are obtained. By deducing the relationship between photon flux and photoionization term, the photon distribution function is analyzed, and the variation law of the photon flux (the number density of photons generated per second) of the streamer moving in the air is obtained. The results show that the maximum luminous point concentrates on the fast-moving head of the positive streamer in the air. The photon flux (the number of photons produced per second) is approximately exponential with the distance from the cathode, with a maximum of approximately 1.4×1028 s-1·m-3.

    Figures and Tables | References | Related Articles | Metrics
    Estimation Method for Metal Damage Struck by Lightning Considering Probability Distribution of Lightning Current Parameters
    LI Tianwei, LIU Lei, CHEN Jian
    2020, 54 (12):  1252-1258.  doi: 10.16183/j.cnki.jsjtu.2019.115
    Abstract ( 656 )   HTML ( 5 )   PDF (788KB) ( 259 )   Save

    Taking the commonly used metal material aluminum 3003 as an example, and based on the simulated lightning current metal damage test results in the four typical compositions of actual lightning current, the damage characterization parameters such as damage area and damage depth of aluminum 3003 alloy and lightning current parameters were analyzed. Taking the building as an example, and based on the parameter analysis of the combined probability distribution of lightning strike density, lightning interception area, lightning current amplitude and transferred charge amount, the annual average number of lightning strikes and the distribution characteristics of lightning current parameters of metal materials were calculated. A damage estimation method considering the probability distribution of lightning current parameters when a metal material with aluminum 3003 alloy and building carrier as an example was subjected to lightning strikes was established. The results show that the damage depth of the aluminum 3003 alloy material under the action of short-term first return current component and short-duration subsequent return current component is less than 0.1 mm, which can be ignored. The damage area of the aluminum 3003 alloy material is proportional to the magnitude of the lightning current suffered, and the damage depth of the alloy is proportional to the amount of charge transferred by the lightning current.

    Figures and Tables | References | Related Articles | Metrics
    Detection Algorithm of Ship Wake in SAR Images
    ZHAO Ting, WANG Shentao, NIU Lin, XI Peili, CAI Yunze
    2020, 54 (12):  1259-1268.  doi: 10.16183/j.cnki.jsjtu.2019.311
    Abstract ( 925 )   HTML ( 14 )   PDF (11518KB) ( 443 )   Save

    In order to solve the problem of ship wake detection in synthetic aperture radar (SAR) image, a coherent speckle noise suppression algorithm based on analytic dictionary and a wake detection algorithm based on Radon transform are proposed. First, the morphological component separation algorithm based on analytic dictionary is used to separate the components of SAR image. The structural component image with ship wake and the texture component image with speckle noise and sea clutter are obtained. Then, the local Radon transform is performed on the structural component that contains the ship wakes. Finally, the real and false local peak points are distinguished by the ship wake recognition algorithm based on peak clustering decision, so as to obtain the local peak points generated by the real wakes and determine the specific position of the ship wakes. The experimental results show that the proposed algorithm can effectively detect the ship wakes in SAR images.

    Figures and Tables | References | Related Articles | Metrics
    Unsupervised Regression Model of Geodesic Flow Kernel Based on Dynamic Independent Component Analysis and Dynamic Principal Component Analysis
    LAI Yanbo, YAN Gaowei, CHENG Lan, CHEN Zehua
    2020, 54 (12):  1269-1277.  doi: 10.16183/j.cnki.jsjtu.2020.171
    Abstract ( 763 )   HTML ( 5 )   PDF (1199KB) ( 318 )   Save

    It is difficult to accurately measure parameters by using the traditional soft sensor algorithm when the working condition of industrial process is changed. Therefore, a transfer learning strategy is introduced based on geodesic flow kernel to solve this problem. At the same time, the method is optimized to solve the problems of dynamic characteristic extraction and incomplete Gaussian distribution in industrial process. The augmented matrix is first constructed to deal with the dynamic characteristics of the process. Independent component analysis and principal component analysis are performed on the processed data to extract the non-Gaussian and Gaussian information of the source domain and the target domain. Then, the non-Gaussian and Gaussian information of the source domain is adapted to the target domain respectively on the Grassmann manifold. Finally, the maximum mean discrepancy is used to measure the distribution between the source domain and the target domain after domain adaptation, and the calculated results are applied to construct the weight of the model based on the source domain after domain adaptation. The results show that the method not only reduces the difference of distribution between the source domain and the target domain, but also solves the problems of dynamic characteristic extraction and incomplete Gaussian distribution in industrial process. The validity and the practicability of the model are proved by experiments on Tennessee Eastman data.

    Figures and Tables | References | Related Articles | Metrics
    Modeling and Optimization of Robust Scheduling Template Considering Equipment Failure
    FANG Jia, LU Zhiqiang
    2020, 54 (12):  1278-1290.  doi: 10.16183/j.cnki.jsjtu.2019.146
    Abstract ( 610 )   HTML ( 2 )   PDF (1868KB) ( 290 )   Save

    In order to solve the scheduling problem of aircraft moving assembly line in uncertainty environment, this paper proposes a perceptron-dependent fruit fly optimization algorithm(PDFOA) to generate the assembly scheduling template with strong robustness. The proposed PDFOA, taking the fruit fly optimization algorithm as the basis, designs narrow-field osphresis-search operation and narrow-field vision-search operation which is helpful for searching and choosing neighborhood solutions. Simultaneously, the PDFOA sets up a memory library to enhance the global search ability. Finally, simulation experiments are conducted using different testing samples on different job scales. The proposed PDFOA is compared with tabu search, the genetic algorithm and the immune particle swarm optimization algorithm. The results demonstrate the effectiveness of the PDFOA.

    Figures and Tables | References | Related Articles | Metrics
    A Discrete Sine Optimization Algorithm for No-Idle Flow-Shop Scheduling Problem
    ZHAO Rui, GU Xingsheng
    2020, 54 (12):  1291-1299.  doi: 10.16183/j.cnki.jsjtu.2019.321
    Abstract ( 773 )   HTML ( 6 )   PDF (1184KB) ( 374 )   Save

    Aimed at the no-idle flow-shop scheduling problem (NIFSP) with minimized makespan, a discrete sine optimization algorithm (DSOA) is proposed. Inspired by sine waveforms, the original sine optimization algorithm (SOA) is a global optimization algorithm, which uses the sine function to update the position of search agents. First, the update position strategy to adapt to the combinatorial optimization problem is redefined. An iterated greedy algorithm with a variable removing size is employed to update the position to enhance the exploration ability. Then, a crossover strategy and a selection strategy are applied to avoid the algorithm falling into local optimum. Next, to improve the exploitation ability of local search and the accuracy of the algorithm, an insertion-based local search scheme is applied in DSOA to search for a better solution around the current optimal solution. Finally, based on the Taillard benchmark, the simulation results of performance comparisons are presented. The experimental results demonstrate the effectiveness of the proposed DSOA algorithm for solving NIFSP.

    Figures and Tables | References | Related Articles | Metrics
    Analysis of Non-Darcy Flow in Aquitard at Bottom of Foundation Pit Under Fluctuation of Confined Water
    YING Hongwei, XU Dingye, WANG Di, ZHANG Lisha
    2020, 54 (12):  1300-1306.  doi: 10.16183/j.cnki.jsjtu.2019.036
    Abstract ( 679 )   HTML ( 4 )   PDF (912KB) ( 264 )   Save

    In order to better explain the phenomenon of foundation pit inrush caused by confined water, the Hansbo non-Darcy seepage theory was introduced into the Terzaghi one-dimensional saturated soil consolidation equation. Finite difference methods were applied to the numerical solution of excess pore pressure caused by the fluctuation of confined water. Then, the numerical solution was reduced to Darcy seepage and compared with the analytical solution. The effects of non-Darcy parameters, fluctuation periods of confined water, and initial water levels on the variation of excess pore pressure in the aquitard were analyzed. The results show that the excess pore pressure in aquitard volatility increases over time under the fluctuation of confined water, and reaches a stable fluctuating state after several cycles. The greater the initial hydraulic gradient and test constant of non-Darcy, the more obvious the hysteresis phenomenon of excess pore pressure, and the smaller the amplitude. The longer period of pressure water fluctuation or the higher the initial water level, the greater the amplitude of excess pore pressure oscillation. In addition, when the base is subjected to higher levels of initial confined water, the excess pore pressure in aquitard becomes more susceptible to the change of confined water pressure. The application of a case indicates that the designed drawdown depth of the confined water level could be reduced if the non-Darcy factor is considered.

    Figures and Tables | References | Related Articles | Metrics
    Influence of Strengthened Node Arrangement on Pull-Out Characteristics of Biaxial Geogrid
    ZHANG Mengxi, MA Yuan, QIU Chengchun
    2020, 54 (12):  1307-1315.  doi: 10.16183/j.cnki.jsjtu.2019.275
    Abstract ( 734 )   HTML ( 2 )   PDF (3836KB) ( 250 )   Save

    With the development of the geotechnical reinforcement technology, the form of reinforcing materials tends to be three-dimensional. Strengthened blocks of a certain thickness are attached to the joints of the longitudinal and transverse ribs of an ordinary biaxial geogrid so that it becomes a geogrid with strengthened nodes with a three-dimensional reinforcement effect. The layout of the strengthened nodes is divided into two types: upper and lower bilateral arrangement and upper unilateral arrangement, in which the total node thickness was the same. To explore the complex interaction mechanism of the reinforced soil interface, a series of indoor pull-out tests are conducted to investigate the influence of strengthened node arrangement on the characteristics of the reinforced soil interface. Based on the punching shear failure mechanism, the reinforcing mechanism of strengthened nodes is analyzed and the theoretical model of ultimate pull-out resistance is obtained. The results show that the ultimate pull-out resistance of the geogrid with strengthened nodes has a positive correlation with normal stress and node thickness. At the same normal stress, compared with the ordinary geogrid, the ultimate pull-out resistance of the two layout types of strengthened nodes is improved to some extent. The highest improvement rates are 118.33% and 96.73%, respectively. The interface apparent friction coefficient, pseudo cohesion, and comprehensive friction angle increase simultaneously. The ultimate pull-out resistance of the upper and lower bilateral arrangement is bigger than that of the upper unilateral arrangement. The error between the theoretical value based on the punching shear failure mode and the experimental value is less than 10%, and the strengthened node significantly improves the pull-out resistance of the geogrid.

    Figures and Tables | References | Related Articles | Metrics
    Modified p-y Curves Method Based on Degradation Stiffness Model of Sand
    HU Anfeng, NAN Bowen, CHEN Yuan, FU Peng
    2020, 54 (12):  1316-1323.  doi: 10.16183/j.cnki.jsjtu.2019.094
    Abstract ( 881 )   HTML ( 2 )   PDF (1427KB) ( 345 )   Save

    Most of the existing p-y curves are based on the model test results of small-diameter pile under cyclic loading of finite times, which makes it difficult to accurately describe the displacement accumulation of large-diameter pile under long-term horizontal cyclic loading and the cyclic weakening characteristics of soil. Therefore, based on the subroutine provided by Abaqus, a stiffness degradation model of the pile-soil system considering the long-term cyclic weakening effect of sand was established, and the p-y curves of large-diameter pile were obtained based on numerical analysis. Then, by introducing the concept of cyclic reaction ratio, the stiffness degradation factor of the pile-soil system was obtained, and the initial foundation reaction modulus was modified as well. Finally, a modified p-y curves method based on the degradation stiffness model of sand was proposed. By comparing with the test results, the validity of this method is verified. This modified p-y curves method, which is able to consider the effects of loading characteristics, number of cycles, cyclic weakening of sand stiffness, provides a concise and effective analysis method for the preliminary design of monopile foundation under long-term horizontal cyclic loading.

    Figures and Tables | References | Related Articles | Metrics
    Discrete Topology Optimization of Body-in-White Welding Production Platform Based on NSGA-III
    GAO Yunkai, MA Chao, LIU Zhe, TIAN Linli
    2020, 54 (12):  1324-1334.  doi: 10.16183/j.cnki.jsjtu.2020.99.001
    Abstract ( 871 )   HTML ( 7 )   PDF (3514KB) ( 483 )   Save

    This paper proposes a modified third generation non-dominated sorting genetic algorithm (mNSGA-III) to overcome the poor convergence of third generation non-dominated sorting genetic algorithm (NSGA-III) in handling discrete topology optimization. It uses the mNSGA-III for the structural optimization of a body-in-white (BIW) welding production platform. It proposes an advanced extreme point selection to stabilize the normalization of populations. It constructs the finite element model of BIW welding production platform. Using discrete topology optimization, it treats the total mass, maximum stress and z-direction displacements of several nodes of platform as objective functions. It developed a discrete topology optimization program by using MATLAB interfaced the commercial finite element code MSC.Nastran. Finally, it selected the design with appropriate layout in view of stiffness and strength of the structure. The optimal design conforms to the design standards and the total mass reduces by 30.1%. The results show that mNSGA-III gets a more stable optimization process and easy to converge when solving the multi-objective discrete topology optimization problems. The proposed method provides an applicable method for the optimization of giant steel structures and has great values for practical engineering problem.

    Figures and Tables | References | Related Articles | Metrics
    Design and Synthesis of a Novel Primary Amine-Thiourea Organocatalyst Based on Unactivated C(sp3)-H Amination Reaction
    LIAN Pengfei, WANG Xunhui, ZHANG Shuyu
    2020, 54 (12):  1335-1339.  doi: 10.16183/j.cnki.jsjtu.2020.144
    Abstract ( 717 )   HTML ( 3 )   PDF (597KB) ( 423 )   Save

    In order to apply the C-H activation strategy to the synthesis of novel organic catalysts, a novel primary amine-thiourea catalyst is designed and synthesized by using the developed inert C(sp3)-H amination method as a key step. First, using phenylalanine as the substrate and di-tert-butyl-azodicarboxylic acid as the nitrogen source, the corresponding amination products are obtained by employing the Pd-catalyzed inert C(sp3)-H amination method. Next, the chiral skeleton of 1,2-diamine privileged in organocatalysts is obtained by simple conversion. Then, a novel chiral primary amine-thiourea bifunctional organic catalyst is synthesized, whose structure is characterized by nuclear magnetic resonance (NMR) and high resolution mass spectrometry (HRMS). The synthesized catalyst is also successfully applied to the asymmetric Michael addition reaction of isobutyraldehyde with nitroolefins. Due to the advantages of transition metal-catalyzed C-H activation, such as simplicity, high efficiency, high atomic economy, and non pre-functionalization, its application to the development of small molecular catalysts will undoubtedly make the structure of catalyst more diversified and the synthesis process more efficient.

    Figures and Tables | References | Related Articles | Metrics
    Online State of Charge Estimation for Battery in Electric Vehicles Based on Forgetting Factor Recursive Least Squares
    CHEN Yushan, QIN Linlin, WU Gang, MAO Junxin
    2020, 54 (12):  1340-1346.  doi: 10.16183/j.cnki.jsjtu.2020.172
    Abstract ( 1038 )   HTML ( 9 )   PDF (1323KB) ( 1045 )   Save

    An advanced battery management system ensures the safe and efficient use of batteries in electric vehicles. As the state of charge (SOC) cannot be measured directly, it is important for the battery management system to accurately and reliably estimate the SOC of batteries. In order to estimate SOC, a first-order resistor-capacitance (RC) equivalent circuit model is used to describe the external characteristic of batteries. The model parameters are identified by forgetting factor recursive least-squares (FFRLS). Open circuit voltage (OCV) is one of the model parameters, and then SOC can be estimated by the SOC-OCV model. The CALCE battery research group in the University of Maryland has proposed some data, which include the data of LNMC/graphite battery working under dynamic stress test (DST) and Beijing dynamic stress test (BJDST) conditions. These data are used to verify the proposed algorithm. The results show that the estimation error does not exceed 3.419 0% in DST and 4.233 5% in BJDST, which indicates that the proposed method can realize online SOC estimation.

    Figures and Tables | References | Related Articles | Metrics