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IEEE/CAA Journal of Automatica Sinica 2024年第6期11卷 1485-1498页

作者： You Zhao Xing He mingliang zhou Tingwen Huang Chongqing Key Laboratory of Nonlinear Circuits and Intelligent Information Processing College of Electronic and Information EngineeringSouthwest UniversityChongqing 400715China School of Computer Science Chongqing UniversityChongqing 400044China Department of Mathematics Texas A&M University at QatarDoha 23874Qatar IEEE

The Nesterov accelerated dynamical approach serves as an essential tool for addressing convex optimization problems with accelerated convergence *** previous studies in this field have primarily concentrated on unconstrained smooth con-vex optimization *** this paper,on the basis of primal-dual dynamical approach,Nesterov accelerated dynamical approach,projection operator and directional gradient,we present two accelerated primal-dual projection neurodynamic approaches with time scaling to address convex optimization problems with smooth and nonsmooth objective functions subject to linear and set constraints,which consist of a second-order ODE(ordinary differential equation)or differential conclusion system for the primal variables and a first-order ODE for the dual *** satisfying specific conditions for time scaling,we demonstrate that the proposed approaches have a faster conver-gence *** only requires assuming convexity of the objective *** validate the effectiveness of our proposed two accel-erated primal-dual projection neurodynamic approaches through numerical experiments.

关键词： Accelerated projection neurodynamic approach lin-ear and set constraints projection operators smooth and nonsmooth convex optimization time scaling.

Failure responses of rock tunnel faces during excavation through the fault-fracture zone

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Underground Space 2023年第3期10卷 166-181页

作者： Zeyu Li Hongwei Huang mingliang zhou Dongming Zhang Department of Geotechnical Engineering Tongji UniversitySiping Road 1239Shanghai 200092China

It is essential to cast light on the construction risks in tunnel excavations through the fault-fracture zone(FFZ).This study adopts the material point method(MPM)to simulate the failure responses of a rock tunnel face during excavation through the FFZ.A numerical study was conducted to compare a physical model test and validate the feasibility of using the MPM in simulating tunnel face *** hundred ninety numerical simulation cases were constructed to represent a rock tunnel excavation project with different site *** simulation results suggest that the cohesion and the friction angle significantly influence failure *** tunnel cover depth can magnify the failure responses,and the FFZ thickness significantly affects the mobilized rock mass volume when the FFZ consists of a weak rock *** numerical simulation results suggest three deformation patterns:face bulge,partial failure,and slide *** failure responses can be characterized by stress arch,slip surface,angle of reposing,and influence *** insights suggested by the face failure responses during excavation through the FFZ can aid field engineers in determining the scope of possible damage,and in establishing emergency measures to minimize losses if such failure occurs.

关键词： Tunnel face failure Rock tunnel excavation Large deformation Fracture fault zone Material point method

Novel SfM-DLT method for metro tunnel 3D reconstruction and Visualization

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Underground Space 2021年第2期6卷 134-141页

作者： Yadong Xue Sen Zhang mingliang zhou Hehua Zhu Key Laboratory of Geotechnical and Underground Engineering of Education Ministry Tongji UniversityShanghai 200092China Department of Geotechnical Engineering Tongji UniversityShanghai 200092China

Metro tunnels play a crucial role in urban ***,with growing tunnel operation periods,defects,and large deformations appearing,these are influencing tunnel structural performance and threatening public ***-dimensional(3D)tunnel reconstruction is an effective way to highlight tunnel conditions and provide a basis for engineering management and ***,the current methods of tunnel 3D reconstruction do not sufficiently combine the qualitative and quantitative characteristics of tunnel *** this study,a novel method for metro tunnel 3D reconstruction based on structure from motion(SfM)and direct linear transformation(DLT)is *** dimensionless 3D reconstruction point cloud acquired through the SfM method showcases the qualitative characteristics(such as leakage and pipelines)of the tunnel *** close-range photogrammetry DLT method provides scale information missing from the SfM method and quantitative characteristics(such as profile deformation)of the tunnel *** SfM-DLT method was tested in a Shanghai metro tunnel,and proved to be feasible and promising for future tunnel inspections.

关键词： Metro tunnel 3D reconstruction Visualization Structure from motion Direct linear transformation

Micromixing performance of the teethed high shear mixer under semi-batch operation

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Frontiers of Chemical Science and Engineering 2022年第4期16卷 546-559页

作者： Xiaoning Li Lin Yang Junheng Guo Wei Li mingliang zhou Jinli Zhang School of Chemical Engineering and Technology Tianjin UniversityTianjin 300350China Department of Geotechnical Engineering Tongji UniversityShanghai 200092China School of Chemistry and Chemical Engineering Shihezi UniversityShihezi 832003China

Semi-batch operated reaction processes are necessary for some competitive reaction systems to achieve a desirable process selectivity and productivity of fine chemical *** the structural and operating parameters of the teethed high shear mixers were adjusted to study the micromixing performance in the semi-batch operated system,using the Villermaux/Dushman reaction *** results indicate that the rising of the rotor speed and the number of rotor teeth,the decrease of the width of the shear gap and the radial distance between the feed position and the inner wall of stator can enhance the micromixing level and lead to the decrease of the segregation ***,computational fluid dynamics calculations were carried out to disclose the evolution of the flow pattern and turbulent energy dissipation rate of the semi-batch operated high shear ***,the correlation was established with a mean relative error of 8.05%and R^(2)of 0.955 to fit the segregation index and the parameters studied in this work,which can provide valuable guidance on the design and optimization of the semi-batch operated high shear mixers in practical applications.

关键词： high shear mixer semi-batch operation micromixing performance Villermaux Dushman system segregation index

Rock mass quality prediction on tunnel faces with incomplete multi-source dataset via tree-augmented naive Bayesian network

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International Journal of Mining Science and Technology 2024年第3期34卷 323-337页

作者： Hongwei Huang Chen Wu mingliang zhou Jiayao Chen Tianze Han Le Zhang Key Laboratory of Geotechnical and Underground Engineering of Ministry of Education Tongji UniversityShanghai 200092China Department of Geotechnical Engineering Tongji UniversityShanghai 200092China School of Civil Engineering Beijing Jiaotong UniversityBeijing 100044China Qingdao Guoxin Second Jiaozhou Bay Subsea Tunnel Co. Ltd.Qingdao 266071China

Rock mass quality serves as a vital index for predicting the stability and safety status of rock tunnel *** tunneling practice,the rock mass quality is often assessed via a combination of qualitative and quantitative ***,due to the harsh on-site construction conditions,it is rather difficult to obtain some of the evaluation parameters which are essential for the rock mass quality *** this study,a novel improved Swin Transformer is proposed to detect,segment,and quantify rock mass characteristic parameters such as water leakage,fractures,weak *** site experiment results demonstrate that the improved Swin Transformer achieves optimal segmentation results and achieving accuracies of 92%,81%,and 86%for water leakage,fractures,and weak interlayers,respectively.A multisource rock tunnel face characteristic(RTFC)dataset includes 11 parameters for predicting rock mass quality is *** the limitations in predictive performance of incomplete evaluation parameters exist in this dataset,a novel tree-augmented naive Bayesian network(BN)is proposed to address the challenge of the incomplete dataset and achieved a prediction accuracy of 88%.In comparison with other commonly used Machine Learning models the proposed BN-based approach proved an improved performance on predicting the rock mass quality with the incomplete *** utilizing the established BN,a further sensitivity analysis is conducted to quantitatively evaluate the importance of the various parameters,results indicate that the rock strength and fractures parameter exert the most significant influence on rock mass quality.

关键词： Rock mass quality Tunnel faces Incomplete multi-source dataset Improved Swin Transformer Bayesian networks

Face stability analysis of circular tunnels in layered rock masses using the upper bound theorem

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Journal of Rock Mechanics and Geotechnical Engineering 2022年第6期14卷 1836-1871页

作者： Jianhong Man mingliang zhou Dongming Zhang Hongwei Huang Jiayao Chen Key Laboratory of Geotechnical and Underground Engineering of Ministry of Education Department of Geotechnical EngineeringTongji UniversityShanghai200092China

An analysis of tunnel face stability generally assumes a single homogeneous rock ***,most rock tunnel projects are excavated in stratified rock *** paper presents a two-dimensional(2D)analytical model for estimating the face stability of a rock tunnel in the presence of rock mass *** model uses the kinematical limit analysis approach combined with the block calculation technique.A virtual support force is applied to the tunnel face,and then solved using an optimization method based on the upper limit theorem of limit analysis and the nonlinear Hoek-Brown yield *** design charts are provided to analyze the effects of rock layer thickness on tunnel face stability,tunnel diameter,the arrangement sequence of weak and strong rock layers,and the variation in rock layer parameters at different *** results indicate that the thickness of the rock layer,tunnel diameter,and arrangement sequence of weak and strong rock layers significantly affect the tunnel face *** in the parameters of the lower layer of the tunnel face have a greater effect on tunnel stability than those of the upper layer.

关键词： Face stability Rock tunnel Layered rock masses Upper bound solution Hoek—Brown criterion

Machine learning-based classification of rock discontinuity trace:SMOTE oversampling integrated with GBT ensemble learning

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International Journal of Mining Science and Technology 2022年第2期32卷 309-322页

作者： Jiayao Chen Hongwei Huang Anthony G.Cohn Dongming Zhang mingliang zhou Key Laboratory of Geotechnical and Underground Engineering of Ministry of Education Department of Geotechnical EngineeringTongji UniversityShanghai 200092China School of Computing University of LeedsLS29JT LeedsUnited Kingdom Department of Computer Science and Technology Tongji UniversityShanghai 211985China School of Civil Engineering Shandong UniversityJinan 250061China Luzhong Institute of Safety Environmental Protection Engineering and MaterialsQingdao University of Science and TechnologyZibo 255000China School of Mechanical and Electrical Engineering Qingdao University of Science and TechnologyQingdao 260061China

This paper presents a hybrid ensemble classifier combined synthetic minority oversampling technique(SMOTE),random search(RS)hyper-parameters optimization algorithm and gradient boosting tree(GBT)to achieve efficient and accurate rock trace identification.A thirteen-dimensional database consisting of basic,vector,and discontinuity features is established from image *** data points are classified as either‘‘trace”or‘‘non-trace”to divide the ultimate results into candidate trace *** is found that the SMOTE technology can effectively improve classification performance by recommending an optimized imbalance ratio of 1:5 to 1:***,sixteen classifiers generated from four basic machine learning(ML)models are applied for performance *** results reveal that the proposed RS-SMOTE-GBT classifier outperforms the other fifteen hybrid ML algorithms for both trace and nontrace ***,discussions on feature importance,generalization ability and classification error are conducted for the proposed *** experimental results indicate that more critical features affecting the trace classification are primarily from the discontinuity ***,cleaning up the sedimentary pumice and reducing the area of fractured rock contribute to improving the overall classification *** proposed method provides a new alternative approach for the identification of 3D rock trace.

关键词： Tunnel face Rock discontinuity trace Machine learning Gradient boosting tree Generalization ability

Study on Electromagnetic-Fluid-Temperature Multiphysics Field Coupling Model for Drum of Mine Cable Winding Truck

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CES Transactions on Electrical Machines and Systems 2021年第2期5卷 133-142页

作者： Weihua Chen mingliang zhou Xiaoheng Yan Zhengxing Li Xiaoxue Lin the School of Liaoning Technical University(Huludao) Liaoning Huludao 125100China

Aiming at solving problems of low efficiency,low cable capacity in current 300m open-pit mine cable winding truck,a 900 m cable winding plan was *** this paper,the mechanism of the thermal effect of the cable was described,and a two-dimensional axisymmetric electromagnetic-fluid-temperature multiphysics coupling model of the cable reel was established regarding the 900m cable reel as independent *** the structure of the drum,the number of cable winding layers,the factors of heat conduction,heat radiation and convective heat transfer in the actual working process,the steady state analysis of the multi-physical field coupling was carried *** sum of the losses of each part of the cable was obtained through the calculation of electromagnetic field,which was used as a heat source to calculate and analyze the temperature distribution of different layers of cable winding,as well as the temperature distribution and heat dissipation characteristics of different structures of the *** results show that three layers of cable winding is the best *** lowest temperature of closed cylindrical drum is 70℃after heat dissipation,which has obvious advantages compared with the lowest temperature of 85℃after heat dissipation of squirrel-cage cylindrical *** results provide a reliable theoretical basis for the research and development of a new type of mine cable winding truck with 900 m cable capacity.

关键词： Heat dissipation characteristics mine cable winding truck multiphysics coupling temperature distribution

An Injectable silk-based hydrogel as a novel biomineralization seedbed for critical-sized bone defect regeneration

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Bioactive Materials 2024年第5期35卷 274-290页

作者： Yuhui Zhu Hao Gu Jiawei Yang Anshuo Li Lingli Houh mingliang zhou Xinquan Jiang Department of Prosthodontics Shanghai Ninth People’s HospitalShanghai Jiao Tong University School of MedicineNo.639 Zhizaoju RoadShanghai200011China College of Stomatology Shanghai Jiao Tong UniversityNo.115 Jinzun RoadShanghai200125China National Center for Stomatology No.639 Zhizaoju RoadShanghai200011China National Clinical Research Center for Oral Diseases No.639 Zhizaoju RoadShanghai200011China Shanghai Key Laboratory of Stomatology No.639 Zhizaoju RoadShanghai200011China Shanghai Research Institute of Stomatology No.639 Zhizaoju RoadShanghai200011China Shanghai Engineering Research Center of Advanced Dental Technology and Materials No.115 Jinzun RoadShanghai 200125China Shanghai Institute of Precision Medicine Shanghai Ninth People’s HospitalShanghai Jiao Tong University School of MedicineNo.115 Jinzun RoadShanghai200125China

The healing process of critical-sized bone defects urges for a suitable biomineralization environment. However, the unsatisfying repair outcome usually results from a disturbed intricate milieu and the lack of in situ mineralization resources. In this work, we have developed a composite hydrogel that mimics the natural bone healing processes and serves as a seedbed for bone regeneration. The oxidized silk fibroin and fibrin are incorporated as rigid geogrids, and amorphous calcium phosphate (ACP) and platelet-rich plasma serve as the fertilizers and loam, respectively. Encouragingly, the seedbed hydrogel demonstrates excellent mechanical and biomineralization properties as a stable scaffold and promotes vascularized bone regeneration in vivo. Additionally, the seedbed serves a succinate-like function via the PI3K-Akt signaling pathway and subsequently orchestrates the mitochondrial calcium uptake, further converting the exogenous ACP into endogenous ACP. Additionally, the seedbed hydrogel realizes the succession of calcium resources and promotes the evolution of the biotemplate from fibrin to collagen. Therefore, our work has established a novel silk-based hydrogel that functions as an in-situ biomineralization seedbed, providing a new insight for critical-sized bone defect regeneration.

关键词： Silk fibroin Bone regeneration Hydrogel Biomineralization Platelet-rich plasma

Resistance factors for design of slopes in a homogenous soil layer

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Rock Mechanics Bulletin 2023年第1期2卷 17-26页

作者： Chenguang Wu Jie Zhang mingliang zhou Lei Wang Key Laboratory of Geotechnical and Underground Engineering of Ministry of Education and Department of Geotechnical Engineering Tongji UniversityShanghai200092China Department of Civil and Architectural Engineering and Construction Management University of CincinnatiCincinnatiOH45221USA

Traditionally,the factor of safety(FOS)is widely used to account for uncertainties in the design of slopes within the framework of working stress *** the uncertainties involved in the design of slopes vary,the same FOS may correspond to the different levels of *** this study,the advanced first order reliability method is used to determine the resistance factors for design of slopes in a homogenous soil *** is found that the resistance factors depend on the target reliability index,the height of the slope,and the variability of the soil strength *** is difficult to suggest a unique set of resistance factors for design of *** solutions are developed to determine the resistance factors for design of slopes assuming the random variables are normally *** approximate method based on the concept of equivalent target reliability index is also suggested to determine the resistance factors for design of the slope when the soil strength parameters are lognormally *** method suggested in this paper provides a practical way to perform load and resistance factors design of slopes.

关键词： Slopes Uncertainties Reliability Resistance factors Sensitivity analysis