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Journal of Rock Mechanics and Geotechnical Engineering 2024年第9期16卷 3798-3811页

作者： Qihua Zhang Shan Dong Yaoqi Liu junjie Huang Feng Xiong Badong National Observation and Research Station of Geohazards China University of GeosciencesWuhan430074China SINOPEC Shanghai Engineering Co. Ltd.Shanghai200120China Faculty of Engineering China University of GeosciencesWuhan430074China

Analyzing rock mass seepage using the discrete fracture network(DFN)flow model poses challenges when dealing with complex fracture *** paper presents a novel DFN flow model that incorporates the actual connections of large-scale ***,this model efficiently manages over 20,000 fractures without necessitating adjustments to the DFN *** geometric analyses,such as identifying connected fractures,dividing the two-dimensional domain into closed loops,triangulating arbitrary loops,and refining triangular elements,are fully *** analysis processes are comprehensively introduced,and core algorithms,along with their pseudo-codes,are outlined and explained to assist readers in their programming *** accuracy of geometric analyses is validated through topological graphs representing the connection relationships between *** practical application,the proposed model is employed to assess the water-sealing effectiveness of an underground storage cavern *** analysis results indicate that the existing design scheme can effectively prevent the stored oil from leaking in the presence of both dense and sparse ***,following extensive modification and optimization,the scale and precision of model computation suggest that the proposed model and developed codes can meet the requirements of engineering applications.

关键词： Discrete fracture network(DFN)flow model Geometric algorithm Fracture flow Water-sealing effect

Comments on‘historical imaginaries,historic urban branding,and the local state in China:rejuvenation discourse,manufactured heritage and simulacrascapes’by Andrew Malcolm law

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Built Heritage 2024年第1期8卷 84-86页

作者： junjie Su School of Ethnology and Sociology Yunnan UniversityNo 2 North Cuihu RoadKunming City 650091YunnanChina

Andrew Malcolm Law's intervention article,‘Historical imaginaries,historic urban branding,and the local state in China:rejuvenation discourse,manufactured heritage and simulacrascapes,presents an interdisciplinary discussion on the construction,in terms of imaginaries and branding,of Chinese historic cities through an investigation of the development and interpretation of the discourse of Chinese national *** article closely examines heritage in Xi'an,China,although the findings and implications may also be relevant to other historic cities/towns in China,which would invite additional studies on both the discourse and practices related to heritage cities in China and across the world.

关键词： discourse law heritage

High spectral efficiency 4-mode 400-km transmission using hybrid probabilistically and geometrically shaped 128QAM

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Science China(Technological Sciences) 2024年第5期67卷 1628-1630页

作者： DING junjie YU JianJun WANG Chen LONG JianYu ZHU Min ZHANG Jiao Pervasive Communication Research Center Purple Mountain LaboratoriesNanjing 211111China Key Laboratory for Information Science of Electromagnetic Waves(MoE) Fudan UniversityShanghai 200433China

Wavelength division multiplexing(WDM)and space division multiplexing(SDM)based on few-mode fiber(FMF)and multi-core fiber(MCF)have been vigorously developed to increase the transmission capacity of optical communication networks[1–5].However,the mode crosstalk generated in the mode division multiplexing(MDM)system causes the correlation between different mode signals,which seriously damages the transmission ***,an effective multiple-input-multiple-output(MIMO)time domain or frequency domain equalizer should be used to eliminate the crosstalk between different mode signals.

关键词： crosstalk fiber multiplexing

Electronic structure engineering of transition metal dichalcogenides for boosting hydrogen energy conversion electrocatalysts

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Chinese Physics B 2024年第9期33卷 13-28页

作者： Bing Hao Jingjing Guo Peizhi Liu junjie Guo Key Laboratory of Interface Science and Engineering in Advanced Materials Ministry of EducationTaiyuan University of TechnologyTaiyuan 030024China

Electrocatalytic water splitting for hydrogen production is an appealing strategy to reduce carbon emissions and generate renewable *** promising process,however,is limited by its sluggish reaction kinetics and high-cost *** two-dimensional(2D)transition metal dichalcogenides(TMDCs)have presented great potential as electrocatalytic materials due to their tunable bandgaps,abundant defective active sites,and good chemical ***,phase engineering,defect engineering and interface engineering have been adopted to manipulate the electronic structure of TMDCs for boosting their exceptional catalytic ***,it is essential to clarify the local structure of catalytically active sites of TMDCs and their structural evolution in catalytic reactions using atomic resolution electron microscopy and the booming in situ technologies,which is beneficial for exploring the underlying reaction *** this review,the growth regulation,characterization,particularly atomic configurations of active sites in TMDCs are *** significant role of electron microscopy in the understanding of the growth mechanism,the controlled synthesis and functional optimization of 2D TMDCs are *** review will shed light on the design and synthesis of novel electrocatalysts with high performance,as well as prompt the application of advanced electron microscopy in the research of materials science.

关键词： TMDCs STEM hydrogen energy conversion active site identification

Demagnetization Analysis and Velocity Tracking Control of In-wheel Motor

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Journal of Harbin Institute of Technology(New Series) 2024年第2期31卷 1-11页

作者： Haihong Li junjie Chen Zhiqi Liu School of Mechanical Engineering Taiyuan University of Science and TechnologyTaiyuan Shanxi 030024China

The error caused by irreversible demagnetization damages the accurate velocity tracking of an in-wheel motor in a mobile robot.A current feedforward vector control system based on ESO is proposed to compensate it for the demagnetization motor.A demagnetization mathematical model is established to describe a permanent magnet synchronous motor,which took the change of permanent magnet flux linkage parameters as a factor to count the demagnetization error in velocity *** uncertain disturbance estimation model of the control system is built based on ESO,which eliminates the system error by the feedforward current *** is compared with the vector control method in terms of control *** simulation results show that the current feedforward vector control method based on ESO reduces the velocity tracking error greatly in conditions of motor demagnetization less than 30%.It is effective to improve the operation accuracy of the mobile robot.

关键词： mobile robot velocity tracking disturbance estimation vector control

Mechanical behavior of rock under uniaxial tension:Insights from energy storage and dissipation

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Journal of Rock Mechanics and Geotechnical Engineering 2024年第7期16卷 2466-2481页

作者： Guanshuang Tan Chunde Ma junjie Zhang Wenyuan Yang Guiyin Zhang Zihao Kang School of Resources and Safety Engineering Central South UniversityChangsha410083China

Many rock engineering projects show that the growth of tensile cracks is often an important cause of engineering disasters,and the mechanical behavior of rocks is essentially the transmission,storage,dissipation and release of *** investigate the tensile behavior of rock from the perspective of energy,uniaxial tension tests(UTTs)and uniaxial compression tests(UCTs)were carried out on three typical rocks(granite,sandstone and marble).Different unloading points were set before the peak stress to separate elastic energy and dissipated *** input energy density ut,elastic energy density ue,and dissipated energy density ud at each unloading point were calculated by integrating stress-strain *** results show that there is a strong linear relationship between the three energy parameters and the square of the unloading stress in UCT,but this linear relationship is weaker in *** ue and ud increase linearly with the increase in ut in UCT and *** on the phenomenon that ue and ud increase linearly with ut,the applicability of W_(et)^(p) index in UTT was proved and the relative energy storage capacity and absolute energy distribution characteristics of three rocks in UCT and UTT were *** tensile behavior of marble and sandstone in UTT can be divided into two stages vaguely according to the energy distribution,but granite is not the *** addition,based on dissipated energy,the damage evolution of three types of rocks in UCT and UTT was *** study provides some new insights for understanding the tensile behavior of rock.

关键词： Uniaxial tension Energy density Mechanical behavior Energy storage coefficient Energy dissipation coefficient

Controlling solid form and crystal habit of triphenylmethanol by antisolvent crystallization in a microfluidic device

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Chinese Chemical Letters 2024年第4期35卷 393-398页

作者： Jun Lu Jinrui Yan Yaohao Guo junjie Qiu Shuangliang Zhao Bo Bao East China University of Science and Technology Shanghai 200237China Guangxi Key Laboratory of Petrochemical Resource Processing and Process Intensification Technology and School of Chemistry and Chemical Engineering Guangxi UniversityNanning 530004China

Crystal habit and crystal form are critical elements in determining product properties and functions. In this work, we developed a microfluidic antisolvent crystallization technique to rapidly screen and accurately control the solid form and crystal habit of triphenylmethanol(Ph_(3)COH). This advanced technique separates the primary mixing of solutions from crystal formation(nucleation and growth) by introducing the microfluidic device, avoiding clogging in microchannels to obtain high-quality crystals. The results show that we can achieve controllable preparation of pure 2Ph_(3)COH·DMSO(DMSO solvate), pure Ph_(3)COH(form β), and mixed crystals with different mass ratios. Moreover, the microscale can prompt the DMSO solvate to grow into hexagonal sheet-like and bulk crystals. We can regulate the aspect ratio of hexagonal sheet-like crystals in binary solvents and control the crystal habit of the form β to transition between long needle-like shapes and short hexagonal prisms in DMF-H_(2)O. Meanwhile, we revealed that the solvent ratio, the antisolvent flow rate, and the initial concentration of Ph_(3)COH are the main factors affecting the solid form selectivity and morphology transition. Such a novel method would be considered as a promising technique to be extended to screen and control key crystallization parameters of other substances.

关键词： Microfluidics Triphenylmethanol Antisolvent crystallization Crystal habit Solid form

A computational model to identify fertility-related proteins using sequence information

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Frontiers of Computer Science 2024年第1期18卷 229-237页

作者： Yan LIN Jiashu WANG Xiaowei LIU Xueqin XIE De WU junjie ZHANG Hui DING Key Laboratory for Animal Disease-Resistance Nutrition of the Ministry of Agriculture Animal Nutrition InstituteSichuan Agricultural UniversityChengdu 611130China School of Life Science and Technology and Center for Informational Biology University of Electronic Science and Technology of ChinaChengdu 610054China

Fertility is the most crucial step in the development process,which is controlled by many fertility-related proteins,including spermatogenesis-,oogenesis-and embryogenesis-related *** identification of fertility-related proteins can provide important clues for studying the role of these proteins in ***,in this study,we constructed a two-layer classifier to identify fertility-related *** this classifier,we first used the composition of amino acids(AA)and their physical and chemical properties to code these three fertility-related ***,the feature set is optimized by analysis of variance(ANOVA)and incremental feature selection(IFS)to obtain the optimal feature *** five-fold cross-validation(CV)and independent data tests,the performance of models constructed by different machine learning(ML)methods is evaluated and ***,based on support vector machine(SVM),we obtained a two-layer model to classify three fertility-related *** the independent test data set,the accuracy(ACC)and the area under the receiver operating characteristic curve(AUC)of the first layer classifier are 81.95%and 0.89,respectively,and them of the second layer classifier are 84.74%and 0.90,*** results show that the proposed model has stable performance and satisfactory prediction accuracy,and can become a powerful model to identify more fertility related proteins.

关键词： sfertility-related proteins machine1 learning sequence information feature selection

Blockchain Meets Generative Behavior Steganography:A Novel Covert Communication Framework for Secure IoT Edge Computing

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Chinese Journal of Electronics 2024年第4期33卷 886-898页

作者： Yuanlong CAO junjie LI Kailin CHAO Jianmao XIAO Gang LEI School of Computer Information Engineering Jiangxi Normal University Jiangxi Blockchain Data Security and Governance Engineering Research Center Jiangxi Normal University School of Software Jiangxi Normal University

The rapid development of Internet of things(Io T) and edge computing technologies has brought forth numerous possibilities for the intelligent and digital future. The frequent communication and interaction between devices inevitably generate a large amount of sensitive information. Deploying a blockchain network to store sensitive data is crucial for ensuring privacy and security. The openness and synchronicity of blockchain networks give rise to challenges such as transaction privacy and storage capacity issues, significantly impeding their development in the context of edge computing and Io T. This paper proposes a reliable fog computing service solution based on a blockchain fog architecture. This paper stores data files in the inter planetary file system(IPFS) and encrypts the file hash values used for retrieving data files with stream cipher encryption. It employs a steganographic transmission technique leveraging Alpha Zero's Gomoku algorithm to discretely transmit the stream cipher key across the blockchain network without a carrier, thus achieving dual encryption. This approach aims to mitigate the storage burden on the blockchain network while ensuring the security of transaction data. Experimental results demonstrate that the model enhances the transmission capacity of confidential information from kilobytes(KB) to megabytes(MB) and exhibits high levels of covert and security features.

关键词： Steganography Ciphers Privacy Data privacy Blockchains Encryption Internet of Things

Impact of surface-reflected seismic waves on the seismic isolation performance of circular tunnel isolation layers

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Journal of Mountain Science 2024年第3期21卷 901-917页

作者： LU Jiahui LUO junjie HUANG Xiangyun HONG Junliang HE YanXin ZHOU Fulin Department of Civil Engineering Xi’an University of Architecture and Technology(XAUAT)Xi’an 710055China Earthquake Engineering Research and Test Centre Guangzhou UniversityGuangzhou 510623China Guangdong Provincial Key Laboratory of Earthquake Engineering and Applied Technology Guangzhou UniversityGuangzhou 510623China Key Laboratory of Earthquake Resistance Earthquake Mitigation and Structural SafetyMinistry of EducationGuangzhou UniversityGuangzhou 510623China

Seismic isolation is an effective strategy to mitigate the risk of seismic damage in ***,the impact of surface-reflected seismic waves on the effectiveness of tunnel isolation layers remains under *** this study,we employ the wave function expansion method to provide analytical solutions for the dynamic responses of linings in an elastic half-space and an infinite elastic *** comparing the results of the two models,we investigate the seismic isolation effect of tunnel isolation layers induced by reflected seismic *** findings reveal significant differences in the dynamic responses of the lining in the elastic half-space and the infinitely elastic ***,the dynamic stress concentration factor(DSCF)of the lining in the elastic half-space exhibits periodic fluctuations,influenced by the incident wave frequency and tunnel depth,while the DSCF in the infinitely elastic space remain ***,the seismic isolation application of the tunnel isolation layer is found to be less affected by surface-reflected seismic *** results provide valuable insights for the design and assessment of the seismic isolation effect of tunnel isolation layers.

关键词： Circular tunnel seismic isolation Surface reflection Response of liners Wave-function expansion method