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    Information & Control
    Design and Simulation of Sliding Mode Controllers for Fractional-Order Singular Systems with Uncertainties
    LI Xi-xiao, YANG Dong-mei
    2022, 43 (11):  1521-1528.  DOI: 10.12068/j.issn.1005-3026.2022.11.001
    Abstract ( 571 )   HTML ( 11)   PDF (875KB) ( 424 )  
    In this paper, sliding mode control is studied for a class of fractional-order singular systems with external disturbances, and an improved exponential reaching law is proposed to eliminate chattering in theory. The integral sliding surface is used to eliminate the approaching phase of sliding mode movement. Kronecker product and LMI method are used to design the gain matrix in order to stabilize the sliding mode equation in both cases: 0<α<1 and 1<α<2. In the design of sliding mode controller, the performance of exponential reaching law is improved, and the sign function is replaced by the designed continuous function, so that when the state approaches the sliding mode, the smooth transition can be achieved with the sliding mode. Finally, the simulation experiments of sliding mode control are established by Simulink to verify the effectiveness of the algorithm in both cases: 0<α<1and 1<α<2.
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    A Demodulation Algorithm for Fiber-Optic F-P Sensor Based on Fast Fourier Transform and Cosine Similarity
    FU Ya-ping, WEN Da, WANG Qiao-yun
    2022, 43 (11):  1529-1535.  DOI: 10.12068/j.issn.1005-3026.2022.11.002
    Abstract ( 434 )   HTML ( 6)   PDF (1282KB) ( 227 )  
    Aiming at the demodulation of the Fabry-Perot(F-P)sensor, a cavity length demodulation algorithm based on fast Fourier transform and cosine similarity(FFT-COSS)is proposed. Firstly, the fast Fourier transform is used to determine the rough measurement value of the cavity length, and then the exact cavity length value is obtained in combination with the cosine similarity algorithm as the final demodulation result of the F-P cavity. Simulation results show that the FFT-COSS algorithm controls the demodulation error to ±0.2nm and the average time of a single demodulation to 1s. The algorithm is applied to a thin-diaphragm F-P sensor micro-pressure test system made of a mixed graphene diaphragm and polymethyl methacrylate(PMMA). Experimental results show that the fitted R-squared of the FFT-COSS algorithm reaches 0.9908 and the cavity length resolution is better than 0.6218nm.The average time of a single demodulation is controlled at 1s, which agrees with the simulation results.
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    The Intervention of Community Evolution Based on Markov Decision Process
    CHAI Pei-hua, MAN Jun-yi, ZENG Yi-feng, CAO Lang-cai
    2022, 43 (11):  1536-1543.  DOI: 10.12068/j.issn.1005-3026.2022.11.003
    Abstract ( 374 )   HTML ( 2)   PDF (921KB) ( 220 )  
    The evolution of the community always tends to be complex and changeable. It becomes an important issue in the field of social networks about how to conduct personalized intervention on communities which are embedded in the network and make different communities evolve toward to different aims. Based on the intervention framework of community evolution, an intervention model based on Markov decision process(MDP)was proposed with the perspective of state transition. With the score of the state dimension and intervention goal, this model establishes the corresponding relationship between the evolution process and MDP, and then models the state, action, and reward in evolution process. Meanwhile, the expected reward of community evolution corresponds to the researcher′s reward. By solving the MDP, the community evolution can be effectively intervened. The experiment results indicated that the community evolution intervention model based on MDP can intervene the community evolution on different true data sets.
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    Online Estimation of State of Health During Discharging of Vehicle Power Battery
    LIU Fang, LIU Yan-peng, LI Jing-dong, BU Fan-tao
    2022, 43 (11):  1544-1551.  DOI: 10.12068/j.issn.1005-3026.2022.11.004
    Abstract ( 330 )   HTML ( 1)   PDF (919KB) ( 254 )  
    According to the characteristics of irregular random charge and discharge of electric vehicles and the requirements of on-line detection, it is difficult to ensure the accuracy of off-line experimental data analysis methods due to battery consistency problems. In this paper, an on-line closed-loop correction SOH (state of health) estimation architecture based on the idea of unscented Kalman filter(UKF)is proposed, which is based on the off-line SOH external indicator function. The advantage of this method is that it can quickly estimate the high-precision SOH value in the random discharge process and the algorithm complexity is relatively reduced. It is easy to implement in practical engineering and the proposed method has better robustness. Through verification, it can be proved that the SOH estimation method proposed in this paper has better practicability and higher estimation accuracy.
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    Whole Process Data Management of Iron and Steel Enterprises Based on Blockchain Technology
    HU Yue-yan , HUANG Min , JIA Da-yu, GAO Zhe-ming
    2022, 43 (11):  1552-1560.  DOI: 10.12068/j.issn.1005-3026.2022.11.005
    Abstract ( 614 )   HTML ( 10)   PDF (1485KB) ( 168 )  
    The effective management of whole process data in iron and steel enterprises guarantees the realization of real-time decision-making. The centralization of the existing whole process data management systems is serious, resulting in weak disaster recovery and security and low efficiency. Using blockchain technology to improve its account mechanism, a scheme of iron and steel whole process data management is designed. Firstly, the business requirements and difficulties of whole process data management are described. Secondly, practical Byzantine fault tolerance(PBFT)consensus mechanism and smart contract technology are adopted to design the structural model of the whole process data management system based on the alliance chain. Thirdly, in view of the disadvantage that traditional blockchain accounts have only one kind of asset, a new account mechanism—multiple asset account is designed, then the corresponding asset conversion algorithm in the account and asset transaction algorithm between accounts are proposed. Finally, the characteristics and efficiency of the system are compared and analyzed. The results show that compared with the traditional centralized system, the system has stronger security, stronger disaster tolerance and higher efficiency.
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    Materials & Metallurgy
    Modeling Research on Influence of Alloy Design on Bainite Transformation Kenitics
    LI Mei-ying, XIAO Nai-you, ZHOU Jian-hua, JIA Tao
    2022, 43 (11):  1561-1569.  DOI: 10.12068/j.issn.1005-3026.2022.11.006
    Abstract ( 440 )   HTML ( 6)   PDF (1467KB) ( 246 )  
    A kinetic model of bainite isothermal transformation based on nucleation-controlled mechanism was used to study the effect of alloy design on bainite transformation kinetics. Using two kinds of high-strength bainite steels, isothermal bainite transformation experiments were conducted at 425~350℃ with a dilatometer. Different degrees of incomplete phase transformation phenomenon are observed. Based on nucleation-controlled mechanism, the displacive transformation kenetic model was used to describe the bainite isothermal transformation behavior of two experimental steels, where grain-boundary nucleation and autocatalytic nucleation were both considered. Finally, the difference in activation energy of nucleation, volume fraction of untransformed austenite and the nucleation rate etc between two experimental steels were comparatively analyzed, which provide theoretical guidance for the composition design and process innovation of high-strength bainite steel.
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    Experimental Study and Application of Temperature-Controlled Quenching for Q960E Ultra High Strength Steel Plates
    YANG Sen-yu, FU Tian-liang, ZHU Mei-jun, WANG Zhao-dong
    2022, 43 (11):  1570-1574.  DOI: 10.12068/j.issn.1005-3026.2022.11.007
    Abstract ( 519 )   HTML ( 2)   PDF (1676KB) ( 100 )  
    The influence of temperature-controlled quenching and conventional quenching on the microstructure and mechanical properties of Q960E ultra-high-strength steel plates, with a thickness of 20, 30 and 40mm, was analyzed using the roller-type jet quenching facility. The microstructure and properties of steel plates under two quenching process conditions were obtained. The results revealed that, when the quenching termination temperature is 40℃, more than 40% of the water consumption can be saved. The surface quality of quenched plates is significantly improved and the flatness is ≤3mm/m. The microstructure of the experimental steel plates processed by temperature-controlled quenching consists of auto-tempered martensite, which is different from the conventional roller-type quenching. The steel plates exhibit excellent comprehensive mechanical properties after temperature-controlled quenching with an average Vickers hardness of ≥420, yield strength of >980MPa, tensile strength of >1000MPa, elongation of >14%. The impact energy is more than 44 J at -40℃.
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    Laser Surface Micro-texturing of Zr-based Bulk Metallic Glass and Investigation of Tribological and Wear Performance
    WANG Qing-hua, CHENG Yang-yang, WANG Hui-xin
    2022, 43 (11):  1575-1582.  DOI: 10.12068/j.issn.1005-3026.2022.11.008
    Abstract ( 469 )   HTML ( 1)   PDF (1905KB) ( 224 )  
    A nanosecond laser-based surface texturing technique,which combined laser surface texturing and low-temperature heat treatment, was developed to functionalize the metallic glass surface. Firstly, laser surface texturing within a specific processing window was utilized to create periodic surface structures on the Zr-based metallic glass, and subsequently heat treatment was employed to control the surface energy/chemistry of the laser textured metallic glass. The experimental results indicated that the laser textured and heat-treated metallic glass surface exhibits changes for both surface structure and surface chemistry, and realizes the wettability transition from superhydrophilicity to superhydrophobicity. In the meantime, the friction test results indicated that the laser textured superhydrophobic surface effectively improves the anti-friction performance with the help of lubrication medium.
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    Mechanical Engineering
    Dual-Robot Pipeline Mapping Method Based on Laser Ranging
    CUI Song-tao, LIANG Jie
    2022, 43 (11):  1583-1590.  DOI: 10.12068/j.issn.1005-3026.2022.11.009
    Abstract ( 450 )   HTML ( 2)   PDF (1691KB) ( 171 )  
    To solve the problem that traditional natural gas pipeline mapping equipment can only map straight pipelines with close distances, a dual-robot pipeline mapping method based on laser ranging is proposed. Pipelines are divided into the horizontal straight pipeline section, the 90° horizontal bent pipeline section, the uphill/downhill pipeline section and the composite pipeline. In this method, the two vehicles move alternately at a uniform speed from the entrance to the exit of the pipeline. Through calculating the distance data captured by the robots, the 3-D model of each section can be obtained. Finally the mapping result of the whole pipeline can be spliced by each section. The experiment results show that this method can map different pipelines, and increase the mapping distance effectively: the distance error in 2000m is within 4m and the error rate is about 0.178%.
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    Generative Adversarial Network Based on Multi-scale Dense Feature Fusion for Image Dehazing
    LIAN Jing, CHEN Shi, DING Kun, LI Lin-hui
    2022, 43 (11):  1591-1598.  DOI: 10.12068/j.issn.1005-3026.2022.11.010
    Abstract ( 384 )   HTML ( 6)   PDF (2161KB) ( 140 )  
    In view of the poor dehazed effect of the existing dehazing networks in real hazy image and the obvious noise in the sky area of the image, a generative adversarial network based on multi-scale dense feature fusion for image dehazing is proposed. The dehazing network uses the produced synthetic foggy data set for adversarial training. Firstly, the dehazing network is designed and the network model is constructed; secondly, a realistic foggy data set is directly generated from the synthetic sunny weather image using deep tags to be suitable for the dehazed field; finally, the network is tested on the real foggy day data set and selects six representative deep learning dehazing networks in recent years for comparison, and non-reference image quality evaluation indicators are used for objective analysis. The research results show that the effect of the proposed dehazing network in real scenes is significantly improved compared to the other networks. The subjective visual effect is significantly better, and the comprehensive performance is better than the other networks in non-reference image quality evaluation indicators.
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    Resources & Civil Engineering
    Mechanical Properties of Deep Buried Altered Hard Rock Under True Triaxial Compression in Sanshandao Gold Mine
    YANG Cheng-xiang, CHEN Xiang-yan, ZHOU Jian-hua
    2022, 43 (11):  1599-1606.  DOI: 10.12068/j.issn.1005-3026.2022.11.011
    Abstract ( 348 )   HTML ( 1)   PDF (4779KB) ( 161 )  
    The triaxial loading tests and the acoustic emission monitoring tests were carried out three types of altered rocks buried in the depth by using the true triaxial loading system and the acoustic emission monitoring system. The deformation, strength, crack evolution process and microscopic failure mechanism of the altered rocks were analyzed. The experimental results show that the mechanical properties of the three types of altered rocks are quite different due to the influence of the dynamic metamorphism and alteration. After alteration, rock sample with high calcite content becomes brittle, and the failure process is severe accompanied by fast release of elastic energy. The strength of the altered rock suffered from severe dynamic metamorphism and carbonate alteration can be reduced, so its ability to resist deformation is weakened and being vulnerable to be damaged.High content of dolomite in the alteration products can lead to the deflection of crack propagation.
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    Experimental Study on Spectral Retrieval of Dustfall in Iron Ore Areas Under Multi-background Conditions
    MA Bao-dong, YANG Xiang-ru, LIU Quan, CHE De-fu
    2022, 43 (11):  1607-1612.  DOI: 10.12068/j.issn.1005-3026.2022.11.012
    Abstract ( 345 )   HTML ( 3)   PDF (1304KB) ( 112 )  
    Dust pollution is serious in some mining areas. Remote sensing could monitor dustfall comprehensively and rapidly. Four kinds of typical backgrounds were selected to carry out iron dustfall spectroscopy measurement to study the accuracy difference of dustfall retrieval. The results show that the retrieval accuracy of plant background was the highest(error is 4.92g/m2) based on 900nm spectral absorption index(SAI)in the hyperspectral model(350~2500nm). By retrieving from the dominant band obtained by the statistical method, the retrieval accuracy on the plant and linoleum roof was relatively high(error is 6.02 and 7.35g/m2, respectively). For the multi-spectral model(according to Landsat-8 OLI bands), the retrieving accuracy on the plant and linoleum roof was also high in the 7th band(error is 6.19 and 7.93g/m2, respectively). In summary, the dustfall retrieval accuracy under the plants background is the highest, which can be used as the first choice for dust fall remote sensing monitoring; if it is limited by the growing season, the background of linoleum roof can be the first choice. If there is no hyperspectral data, the 7th band of multispectral should be the first choice.
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    The Stress Shadow Effect of Multistage Hydraulic Fracturing of Rock Material Based on PHF-LSM Model
    LI Ming, CHEN Zhao, ZHAO Qi, LIANG Li
    2022, 43 (11):  1613-1622.  DOI: 10.12068/j.issn.1005-3026.2022.11.013
    Abstract ( 379 )   HTML ( 5)   PDF (1282KB) ( 158 )  
    The PHF-LSM(permeability-based hydraulic fracture-level set method)hydraulic fracturing numerical model is used to simulate and analyze the stress shadow effect caused by staged fracturing in homogeneous and layered rock materials. Compared with the theoretical solution of single crack induced stress, the feasibility of considering stress shadow effect in PHF-LSM is verified. Based on this model, the influence of rock material parameters and initial stress conditions on induced stress field during the development of single fracture, and the stress shadow effect caused by different fracturing spacing and fracturing sequence during the initiation of multiple fractures in homogeneous and layered rock materials were analyzed. The numerical results show that the increase of Poisson′s ratio, tensile strength and porosity will increase the peak value of the ratio of induced stress to net pressure, while the increase of elastic modulus and horizontal principal stress difference will decrease the peak value. The expansion of crack spacing can weaken the stress shadow effect between cracks. The total fracture area of the two-step fracturing and the sequential fracturing are larger than that of simultaneous fracturing, but sequential fracturing and two-step fracturing will cause higher fracture initiation pressure. The decrease of pay layer thickness and fracturing spacing will increase the stress shadowing effect.
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    Parametric Analysis and Optimization Design of Cable Supported Scissor-Like Deployable Bridge
    LIAO Wei, XU Wei-wei
    2022, 43 (11):  1623-1629.  DOI: 10.12068/j.issn.1005-3026.2022.11.014
    Abstract ( 359 )   HTML ( 6)   PDF (1261KB) ( 190 )  
    Scissor-like bridges can quickly build emergency channels after disasters and improve rescue efficiency. In view of the characteristics of poor stiffness and low material utilization of scissor-like elements(SLEs), a new cable supported scissor-like deployable bridge(CSSDB)for emergency was proposed combined with cable supported system. In order to investigate the behavior of CSSDB, Karamba3D was adopted to establish the finite element model, and parametric analysis was carried out under the action of moving vehicle load, considering the struts’ length and numbers, the SLEs’ cross section, the initial prestress amplitude and the expansion angle. Besides, Galapagos was used to optimize the CSSDB with the minimum structural mass as the optimization objective. The results show that increasing struts’ number, struts’ length and initial prestress can effectively reduce the stress and deflection of SLEs, while the stress and deflection can be increased by increasing expansion angle. Increasing thickeness of SLEs’ cross section reduces stress and increases deflection instead, and the CSSDB’s performance is still dependent on bending of SLEs. The optimization reduces structural mass by 38.89%, and the stress and deflection of CSSDB are 0.25 and 0.2 times than that of the corresponding scissor-like bridge, which proves the superiority of the CSSDB.
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    Deformation Law of Subway Station Constructed by Small Diameter Tube Curtain Method
    WANG Zi-jun, ZHAO Wen, CHENG Cheng, BAI Qian
    2022, 43 (11):  1630-1637.  DOI: 10.12068/j.issn.1005-3026.2022.11.015
    Abstract ( 365 )   PDF (2184KB) ( 137 )  
    Shifudalu station of Shenyang Metro is constructed by small diameter tube curtain construction method. The three-dimensional model of station structure and stratum was built by using FLAC3D. The deformation laws of stratum and the main structure caused by dynamic excavation of small diameter tube curtain were analyzed and summarized. The results show that the surface settlement caused by small diameter tube curtain excavation takes on staged characteristics. Under the influence of group hole effect and pre-support of the pipe curtain, the shape of the settlement tank changes frequently. The ground surface settlement caused by soil excavation between transverse guide tunnels accounts for 50.54% of the final settlement, which is the key stage of ground surface settlement control. After the completion of tube curtain-beam-pile-column construction, the deformation of the main structure shows a good synergistic effect. The vertical deformation of the beam is small at both ends of the station and large in the middle. The horizontal displacement of the side pile and the middle column increased significantly during the negative second storey construction period, and accounts for 47.1% and 55.8% of the maximum horizontal displacement respectively. This stage is the key stage in controlling the deformation of the main structure.
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    Ultrasonic Characteristics of Thermal-Damaged Engineered Cementitious Composites
    CHEN Meng, CAO Yu-xin, WANG Yu-ting
    2022, 43 (11):  1638-1643.  DOI: 10.12068/j.issn.1005-3026.2022.11.016
    Abstract ( 462 )   PDF (1145KB) ( 195 )  
    To study the damage mechanism and ultrasonic properties of thermal-damaged engineered cementitious composites(ECC), ultrasonic monitoring and compression tests were performed on ECC specimens exposed to high temperatures(20, 105, 250, 400, 600 and 800℃). Results indicate that the changes in waveform amplitude, main frequency amplitude, energy, and compressive strength of thermal-damaged ECC are the same; the energy ratio in the 40~50kHz band is the largest, which is about 15% of the total energy in the 0~300kHz band. The wave velocities of ECC specimens heated from 20 to 250 ℃ show no significant changes, and decrease when heated above 400℃. The reason can be relate to free water vaporizes, hydration products decompose, and aggregate physical properties change at high temperature, which leads to the increasing of pore vapor pressure and damaging to the aggregate interfaces, thus the internal cracks in the ECC are generated and expanded. Scanning electron microscopy test results indicate that PVA fiber softens, melts, and vaporizes with increasing temperature. Voids and pores are generated in the ECC matrix and connect with cracks forming into networks, which are beneficial to the releasing of the pore vapor pressure and reducing the thermal damage of ECC. Results also show that the ultrasonic characteristics can effectively reflect the thermal damage evolution process in the ECC.
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    Management Science
    Stochastic Simulation Integrated Method for Multi-relational Blended Uncertain Information and Its Applications
    WANG Lu, YI Ping-tao, LI Wei-wei, DONG Qian-kun
    2022, 43 (11):  1644-1652.  DOI: 10.12068/j.issn.1005-3026.2022.11.017
    Abstract ( 338 )   HTML ( 0)   PDF (1331KB) ( 138 )  
    In view of the problems of the coexistence of multi-source information, incomplete information, and non-independent evaluation questions of evaluation information, an integrated framework for multi-relational blended information and an information aggregation method are proposed. Firstly, the blended uncertain information is classified and integrated, the correlations are explored among information(sub)streams, and the integrated framework for multi-relational blended uncertain information is constructed. Secondly, the blended uncertain information is transformed into random numbers by simulation iterations to fully tap the value of information. Then, through the relationship graph of information(sub)flows, the information weight of information(sub)flows is solved by using the analytic network process(ANP). Finally, by comparing the results of each simulation iteration of the evaluated object, the pairwise priority matrix is obtained, and the probability ranking reflecting the probability characteristics is obtained by the regression tree method. The fusion of blended incomplete information and multi-relational information are explored by constructing the integrated framework for multi-relational blended uncertain information. The requirements for data integrity in the evaluation process are reduced, and information overlapping and information redundancy are considered. The relative conclusion is more explanatory for the practical problems.
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    Evolutionary Game Analysis on the Behavioral Strategies Between Governments and Steel Works: Organic Rankine Cycle Technology Promotion
    ZHANG Chao, ZHANG Xin-xin
    2022, 43 (11):  1653-1661.  DOI: 10.12068/j.issn.1005-3026.2022.11.018
    Abstract ( 374 )   HTML ( 0)   PDF (900KB) ( 111 )  
    An evolutionary game model between Chinese governments and steel works is established to explore how to reasonably promote steel works to use organic Rankine cycle(ORC)technology for recovering low-temperature waste heat, and the influences of evolutionary stability and key parameters on the evolutionary trajectory are analyzed. The results show that implementation costs and environmental pollution taxes are essential for ORC technology promotion. Charging higher taxes on energy consumption and environmental pollution can provide more incentives for governments to promote the application of ORC technology based on maximizing political and social benefits. Both parties benefit from having initial probabilities that are close to or larger than the critical value for popularizing ORC technology. Increasing regulatory expenditures, as well as political and social benefits, motivates governments; adding environmental pollution taxes, ORC generation benefits, and gains from reducing environmental pollution inspires companies; increasing operational loss subsidies and technical allowances, as well as technology deployment costs, is detrimental for both governments and companies.
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    Impact of Consumers’ Perception of Crisis Risks on the Effect of Online Reviews
    GUO Li, LI Jie
    2022, 43 (11):  1662-1672.  DOI: 10.12068/j.issn.1005-3026.2022.11.019
    Abstract ( 348 )   HTML ( 4)   PDF (683KB) ( 220 )  
    Consumer’s perception of crisis risks (PCR) affects online reviews outcome particularly in the public emergency. The model of online reviews affecting consumer purchasing decision was constructed in consumer’s PCR scenarios, and the multiple regression and Bootstrap analysis were used to verify the model. The impact of online reviews including review length, review richness, and review responses on consumer purchasing behavior was discussed. Meanwhile the mediating effect of review helpfulness and the moderating effects of external perceived risks (EPR) and internal perceived risks (IPR) were considered. The results show that review helpfulness has the mediating effect; EPR has positive moderating effect while IPR has negative moderating effect. What’s more, EPR has greater effect on consumer purchasing behavior. Online reviews exert the effect on consumers’ online shopping, which is amplified by the public emergency. Therefore, e-commerce companies should improve online transaction service and online reviews supervision to decrease the consumers’ PCR of online shopping and improve the stable, orderly and sustainable development of e-commerce.
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