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Frontiers of Business Research in China 2022年第2期16卷 151-186页

作者： LIU Yi XIE Kang DENG Honglin School of Business Sun Yat-sen UniversityGuangzhou 510275China

Extant research mostly focuses on the impact of big data on product development(PD)process and performance,and yet there is a lack of theoretical exploration of the transformation path,realization mechanism and transformation paradigm while moving from experience-based PD(EBPD)to data-driven PD(DDPD).This paper,from the integrated perspective of adaptive change and organizational routines,and based on an in-depth case study of HSTYLE,proposes a two-stage transformation model for moving from EBPD to DDPD,dissects the adaptive change mechanism of organizational routines for DDPD,puts forward a theoretical model for the transformation paradigm for DDPD,and provides an innovative interpretation of the connotation of data-driven.This paper constructs a theory for DDPD transformation that comprises three aspects:transformation path,realization mechanism and transformation paradigm.Conclusions of this paper have policy implications for enterprises in their practice on data-driven product innovation in the digital economy era.

关键词： product development transformation data driven organizational routine change adaptive change case study

Evolution of electrochemically induced stress and its effect on the lithium-storage performance of graphite electrode

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Science China(Technological Sciences) 2023年第6期66卷 1784-1796页

作者： HAN Bin SHI BaoQin xie HaiMei kang YiLan Tianjin Key Laboratory of Modern Engineering Mechanics School of Mechanical EngineeringTianjin UniversityTianjin 300350China School of Automobile and Traffic Tianjin University of Technology and EducationTianjin 300222China

The electrochemically induced stress is a key factor that affects the lithium-storage performance of electrode materials.In this study,the origin and evolution of the electrochemically induced stress of the graphite electrode were investigated by in situ experiments and simulations.An in situ optical experiment was performed to observe the electrode color to analyze the concentration and diffusion process of lithium ions inside the graphite electrode.An electrochemical-mechanical coupling model under the same experimental conditions was developed and verified by the experimental lithium concentration,and characterization of the spatiotemporal evolution of the potential,lithium concentration,and stress during the diffusion process was realized.The results showed that lithium intercalation leads to compressive stress,which presents a gradient distribution along the Li+diffusion path,and it exhibits a“piecewise”nonlinear growth trend with increasing lithiation time.In addition,as the potential decreases,the stress increases from slow to fast relative to the lithium-concentration increase,showing the characteristic of stages.The influence of stress on the lithium-storage performance is discussed using the local lithium-intercalation rate and phase-interface migration speed as the key parameters.The lithiation mechanism was analyzed from the perspective of the energy,and it was found that the two factors cause the slow diffusion in the late stage of lithiation,thus affecting the actual lithium-storage performance.This study will enhance the understanding of the electro-chemo-mechanical coupling mechanism and provide guidance for enhancing stress-regulated battery performance.

关键词： graphite electrode electrochemically induced stress evolution electrochemical-mechanical coupling model stress effect lithium-storage performance

Self-supervised learning-based oil spill detection of hyperspectral images

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Science China(Technological Sciences) 2022年第4期65卷 793-801页

作者： DUAN PuHong xie ZhuoJun kang XuDong LI ShuTao College of Electrical and Information Engineering Hunan UniversityChangsha 410082China Key Laboratory of Visual Perception and Artificial Intelligence of Hunan Province Changsha 410082China

Oil spill monitoring in remote sensing field has become a very popular technology to detect the spatial distribution of polluted regions.However,previous studies mainly focus on the supervised detection technologies,which requires a large number of high-quality training set.To solve this problem,we propose a self-supervised learning method to learn the deep neural network from unlabelled hyperspectral data for oil spill detection,which consists of three parts:data augmentation,unsupervised deep feature learning,and oil spill detection network.First,the original image is augmented with spectral and spatial transformation to improve robustness of the self-supervised model.Then,the deep neural networks are trained on the augmented data without label information to produce the high-level semantic features.Finally,the pre-trained parameters are transferred to establish a neural network classifier to obtain the detection result,where a contrastive loss is developed to fine-tune the learned parameters so as to improve the generalization ability of the proposed method.Experiments performed on ten oil spill datasets reveal that the proposed method obtains promising detection performance with respect to other state-of-the-art hyperspectral detection approaches.

关键词： hyperspectral image self-supervised learning data augmentation oil spill detection contrastive loss

Investigation on the stability and anti-eccentric load margin of a novel structure bearing lubricated by low viscosity medium

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Science China(Technological Sciences) 2022年第7期65卷 1613-1633页

作者： xie ZhongLiang JIAO Jian YANG kang HE Tao Department of Engineering Mechanics Northwestern Polytechnical UniversityXi'an 710072China Research&Development Institute of Northwestern Polytechnical University in Shenzhen Shenzhen 518057China School of Mechanical-Electric Engineering Xidian UniversityXi'an 710071China Wuhan Second Ship Design and Research Institute Wuhan 430205China

The paper studies the anti-eccentric load margin of a novel structure bearing lubricated by low viscosity medium. The lubrication dynamic model considering journal inclination angle is established. The effects of different speeds, loads, and tilted angles on the interface attributes of the bearing under typical working conditions are studied. The results show that the special structure bearing has self-stability margin of anti-tilted and anti-eccentric load. Particularly under different speed conditions, analyses show that the eccentric load has little influence on the static/dynamic characteristics of the bearing. Under the same conditions, the stability margin of the bearing is higher than that of traditional bearings. The research provides a theoretical basis for the application of such kinds of special structure bearings.

关键词： water-lubricated bearing tilted angle anti-eccentric load margin lubrication performance

Engineering Innovation and the Development of the BDS-3 Navigation Constellation

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Engineering 2021年第5期7卷 558-563页

作者： Jun xie Chengbin kang China Academy of Space Technology Beijing 100094China

1.Introduction On 23 June 2020,the third geostationary Earth orbit satellite(GEO-3),the last satellite of the China's BeiDou Navigation Satellite System(BDS)-3 space segment construction project,was successfully launched,marking the completion of the BDS global constellation deployment and indicating the successful completion of the BDS“three-step”development strategy.The positioning,navigation,and timing(PNT)service and special-feature services provided by the BDS have been widely used in key infrastructures of the national economy and defense security;they have also promoted a transformation of the production method and upgraded industrial infrastructure in China.

关键词： China. Earth BDS

Crystal-Plasticity-Based Dynamic Constitutive Model of AZ31B Magnesium Alloy at Elevated Temperature and with Explicit Plastic-Strain-Rate Control

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Acta Mechanica Solida Sinica 2020年第1期33卷 31-50页

作者： Qijun xie Zhiwu Zhu Guozheng kang Key Laboratory of Mountain Hazards and Earth Surface Processes Institute of Mountain Hazards and EnvironmentChinese Academy of SciencesChengdu 610041China State Key Laboratory of Traction Power Southwest Jiaotong UniversityChengdu 610031China Applied Mechanics and Structure Safety Key Laboratory of Sichuan Province School of Mechanics and EngineeringSouthwest Jiaotong UniversityChengdu 610031China

In this study,a series of experiments were carried out on the AZ31B magnesium alloy,including both a macro-experiment(mechanical experiment)and a micro-experiment(dislocation observation).Next,based on the consideration of the deformation mechanism of magnesium alloys(dislocation slip and twinning),a dynamic constitutive model of the magnesium alloy was established.In the developed model,the strain-rate-sensitivity control and the effect of temperature on the dynamic mechanical performance of the alloy were also investigated.The model parameters were determined by fitting the macroscopic experimental results.Next,the evolution of the micro-deformation mechanism was calculated by the developed model,and the trend of macro-mechanical behavior was also discussed.

关键词： Magnesium alloy Constitutive model Microscopic mechanism Dynamic test Crystal plasticity

Face stability analysis of large shield-driven tunnel in rock-soil interface composite formations

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Underground Space 2022年第6期7卷 1021-1035页

作者： Xiaobin Ding kang Li Yuxuan xie Shuzhuo Liu School of Civil Engineering and Transportation South China University of TechnologyGuangzhou 510641China Guangdong Provincial Key Laboratory of Modern Civil Engineering Technology South China Institute of Geotechnical EngineeringGuangzhou 510650China

A new 3D log-spiral model(LS-M model)is proposed to determine the minimal support pressure on the tunnel face of a large shielddriven tunnel in rock-soil interface(RSI)composite formations.In the proposed LS-M model,we define the RSI angle ω and use a new approach to calculate the equivalent tunnel face area,which provides a collapse zone with more realistic geometry than the traditional wedge model.And it has acceptable accuracy with simpler implementation than limit equilibrium analysis.Comparing with previous studies and 3D numerical analysis,it indicates that:(i)the LS-M results agree well with others in full-soil formations on the variation patterns of minimum support pressure and stability coefficients N_(c) and N_(γ);(ii)the critical RSI angle ω_(cr),which is predominantly influenced by soil cohesion,increases with the soil property values;(iii)the limit support pressure starts to increase with ω only when ω>ω_(cr);(iv)the peak support pressure occurs at lower C/D with a lower ω;(v)ω can only affect stability coefficients N_(c) and N_(γ) when ω and the friction angle are relatively small,while N_(s) is substantially influenced by RSI angle ω.

关键词： Tunnel Stability Limit support pressure RSI composite formations 3D failure mechanism

A Precoding Scheme to Reduce the Effect of Channel Correlation for MIMO-PLC System

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China Communications 2023年第2期20卷 216-225页

作者： Wangbin Cao Hui kang Xiaolin Liang Zhiyuan xie Xiongwen Zhao School of Electrical and Electronic Engineering North China Electric Power UniversityBaoding 071000/Beijing 102206China School of Electronic and Information Engineering Hebei UniversityBaoding 071002China Hebei Key Laboratory of Power Internet of Things Technology(North China Electric Power University) Baoding 071003China

MIMO technique can provide higher information throughput and transmission reliability for the PLC system.However,the MIMO-PLC system based on three-conductor cable has a high correlation among its sub-channels.Spatial multiplexing technology will be affected by the spatial correlation between MIMO-PLC sub-channels.To reduce the system bit error rate caused by MIMO-PLC correlation among sub-channels,this paper proposed a phase rotation precoding scheme for the 2×2 closed-loop MIMO-PLC system.According to the channel transfer function of high correlation MIMO-PLC system,the phase rotation precoding matrix F is calculated,and the transmission signal matrix S is modulated with the F,the code distance at the receiving point with smallest code distance is increased by phase rotation.Simulation results show that the scheme can effectively reduce the bit error rate of the 2×2 MIMO-PLC system based on ML detection,and significantly improve the system performance.

关键词： carrier transmission on power lines telecommunication cables error correction precoding

Control of the common rail pressure in gasoline engines through an extended state observer based MPC

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Control Theory and Technology 2019年第2期17卷 156-166页

作者： Chao WU kang SONG Hui xie State Key Laboratory of Engines Tianjin UniversityTianjin 300072China

In this paper,a model predictive control(MPC)solution,assisted by extended state observer(ESO),is proposed for the common rail pressure control in gasoline engines.The rail pressure dynamic,nonlinear with large uncertainty,is modeled as a simple first order system.The discrepancy of the model from the real plant is lumped as"total disturbance",to be estimated in real-time by ESO and the n mitigated in the nonlin ear MPC,assuming the total disturbance does not change in the prediction horiz on.The non linear MPC problem is solved using the Newton/generalized minimum residual(GMRES)algorithm.The proposed ESO-MPC solution,is compared with the conventional proportional-integral-differential(PID)controller,based on the high-fidelity model provided in the benchmark problem in IFAC-E-CoSM.Results show the following benefits from using ESO-MPC relative to PID(benchmark):1)the disturbance rejection capability to fuel inject pulse step is improved by 12%in terms of recovery time;2)the transient response of rail pressure is improved by 5%in terms of the integrated absolute tracking error;and 3)the robustness is improved without n eed for gain scheduling,which is required in PID.Additionally,in creasing the ban dwidth of ESO allows reducing the complexity of the model implemented in MPC,while maintaining the disturbance rejection performance at the cost of high noise-sensitivity.Therefore,the ESO-MPC combination offers a simpler and more practical solution for common rail pressure control,relative to the standard MPC,which is consistent with the findings in simulation.

关键词： Rail pressure control fuel system control model predictive control extended state observer active disturbance rejection control

Atmospheric mercury over the marine boundary layer observed during the third China Arctic Research Expedition

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Journal of Environmental Sciences 2011年第9期23卷 1424-1430页

作者： Hui kang Zhouqing xie Institute of Polar Environment University of Science and Technology of China Hefei 230026 China

TGM measurements on board ships have proved to provide valuable complementary information to measurements by a ground based monitoring network.During the third China Arctic Research Expedition （from July 11 to September 24,2008）,TGM concentrations over the marine boundary layer along the cruise path were in-situ measured using an automatic mercury vapor analyzer.Here we firstly reported the results in Japan Sea,North Western Pacific Ocean and Bering Sea,where there are rare reports.The value ranged between 0.30 and 6.02 ng/m 3 with an average of （1.52 ± 0.68） ng/m 3 ,being slightly lower than the background value of Northern Hemisphere （1.7 ng/m 3 ）.Notably TGM showed considerably spatial and temporal variation.Geographically,the average value of TGM in Bering Sea was higher than those observed in Japan Sea and North Western Pacific Ocean.In the north of Japan Sea TGM levels were found to be lower than 0.5 ng/m 3 during forward cruise and displayed obviously diurnal cycle,indicating potential oxidation of gaseous mercury in the atmosphere.The pronounced episode was recorded as well.Enhanced levels of TGM were observed in the coastal regions of southern Japan Sea during backward cruise due primarily to air masses transported from the adjacent mainland reflecting the contribution from anthropogenic sources.When ship returned back and passed through Kamchatka Peninsula TGM increased by the potential contamination from volcano emissions.

关键词： total gaseous mercury atmosphere marine boundary layer Japan Sea North Western Pacific Ocean Bering Sea