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Frontiers of Chemical Science and Engineering 2024年第3期18卷 63-73页

作者： Mengqing Shan Dongshen. Lu Jiatong Dong shen.yan.Jinyu Han Hua wan. Collaborative Innovation Center of Chemical Science and Engineering Key Laboratory for Green Chemical Technology of the Ministry of EducationSchool of Chemical Engineering and TechnologyTianjin UniversityTianjin300354China

Surface engineering and Cu valence regulation are essential factors in improving the C_(2)selectivity during the electrochemical reduction of CO_(2).Herein,we present a sea urchin-like CuO/Cu_(2)O catalyst derived from rhombic dodecahedra Cu_(2)O through one-step oxidation/etching method where the mixed Cu^(+)/Cu^(0)states are formed via in situ reduction during *** combined effects of the morphology and the mixed Cu^(+)/Cu^(0)states on C–C coupling are evaluated by the Faradaic efficiency of C_(2)and the C_(2)/C1 ratio obtained in an H-cell.R-Cu^(O)/Cu_(2)O exhibited 49.5%Faradaic efficiency of C_(2)with a C_(2)/C1 ratio of 3.1 at−1.4 V *** hydrogen electrode,which are 1.5 and 3.2 times higher than those of R-Cu_(2)O,*** a flow-cell,68.0%Faradaic efficiency of C_(2)is achieved at a current density of 500 mA·cm^(−2).The formation of the mixed Cu^(+)/Cu^(0)states was confirmed by in situ Raman ***,the sea urchin-like structure provides more active sites and enables faster electron *** a result,the excellent C_(2)production on R-CuO/Cu_(2)O is primarily attributed to the synergistic effects of the sea urchin-like structure and the stable mixed Cu^(+)/Cu^(0)***,this work presents an integrated strategy for developing Cu-based electrocatalysts for C_(2)production through electrochemical CO_(2)reduction.

关键词： CO_(2)electrolysis sea urchin-like structure Cu^(+)/Cu^(0) C_(2)products

Roof collapse mechanism of weak surrounding rock for deep-buried tunnels under high geostress conditions

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Journal of Mountain Science 2024年第7期21卷 2408-2426页

作者： ZHANG Qi GUO Xiaokang yan.Zhiguo LEI Zhongdai shen.Yixin School of Civil Engineering Southeast UniversityNanjing 211189China Department of Geotechnical Engineering Tongji UniversityShanghai 200092China

High geostress,a typical attribute of tunnels located at significant depths,is crucial in causing stress-induced failure and influencing the stability of the tunnel *** study developed an analytical method for the failure mechanism that occurs in deep-buried tunnel roofs,taking into account the influence of *** limit analysis theory was utilized for deriving analytical solutions about the geometry of the collapsing surface and the limit supporting *** collapsing surface obtained by the analytical solution was validated by the findings of the physical model test,which shows a high level of agreement with the actual *** extensive investigation was done to explore the effects of the lateral pressure coefficients,the tunnel buried depth,the geological conditions of the surrounding rock,the long-short axis ratio,and the size of the tunnel *** findings indicate that an increase in the lateral pressure coefficient from 0.5 to 1.5 results in a reduction in the height of the collapsing zone by 2.08 m and the width of the collapsing zone by 1.15 m,while simultaneously increases the limit supporting pressure by 18.9%.The proposed upper bound method accurately determines the limit supporting pressure and the geometry of the collapsing surface,which aligns well with the results acquired through numerical modelling and on-site monitoring in actual engineering *** proposed analytical method can serve as a reference for similar crown failure issues of deep-buried tunnels.

关键词： Geostress Deep-buried tunnels Collapse mechanism Pressure arch Limit analysis HoekBrown criterion

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Design,preparation,and characterization of a novel ZnO/CuO/Al energetic diode with dual functionality:Logic and destruction

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Defence Technology（防务技术） 2024年第4期34卷 57-68页

作者： Jialu yan. Jiaheng Hu Yinghua Ye Jianbing Xu yan.Hu Ruiqi shen School of Chemistry and Chemical Engineering Nanjing University of Science and TechnologyNanjing 210094China Micro-Nano Energetic Devices Key Laboratory of MIIT Nanjing 210094China Institute of Space Propulsion Nanjing University of Science and TechnologyNanjing 210094China

Self-destructing chips have promising applications for securing *** paper proposes a new concept of energetic diodes for the first time,which can be used for self-destructive chips.A simple two-step electrochemical deposition method is used to prepare ZnO/CuO/Al energetic diode,in which N-type ZnO and P-type CuO are constricted to a PN *** paper comprehensively discusses the material properties,morphology,semiconductor characteristics,and exploding performances of the energetic *** results show that the energetic diode has typical rectification with a turn-on voltage of about 1.78 V and a reverse leakage current of about 3×10^(-4)*** a constant voltage of 70 V loads to the energetic diode in the forward direction for about 0.14 s or 55 V loads in the reverse direction for about 0.17 s,the loaded power can excite the energetic diode exploding and the current rises to about100 *** to the unique performance of the energetic diode,it has a double function of rectification and *** energetic diode can be used as a logic element in the normal chip to complete the regular operation,and it can release energy to destroy the chip accurately.

关键词： Energetic diode ZnO—CuO—Al thermite ZnO/CuO PN junction Electrical explosion performance Self-destructing chips

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Two-Way Neural Network Performance PredictionModel Based onKnowledge Evolution and Individual Similarity

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Computer Modeling in Engineering & Sciences 2024年第2期138卷 1183-1206页

作者： Xinzheng wan. Bing Guo yan.shen College of Computer Science Sichuan UniversityChengdu610065China School of Information Science and Engineering Guilin University of TechnologyGuilin541004China School of Control Engineering Chengdu University of Information TechnologyChengdu610225China

Predicting students’academic achievements is an essential issue in education,which can benefit many stakeholders,for instance,students,teachers,managers,*** with online courses such asMOOCs,students’academicrelateddata in the face-to-face physical teaching environment is usually sparsity,and the sample size is *** makes building models to predict students’performance accurately in such an environment even *** paper proposes a Two-WayNeuralNetwork(TWNN)model based on the bidirectional recurrentneural network and graph neural network to predict students’next semester’s course performance using only theirprevious course *** experiments on a real dataset show that our model performs better thanthe baselines in many indicators.

关键词： Computer education performance prediction deep learning

Efficient stochastic parallel gradient descent training for on-chip optical processor

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Opto-Electronic Advances 2024年第4期7卷 5-15页

作者： Yuanjian wan.Xudong Liu Guangze Wu Min yan. Guofeng yan.Yu Zhang Jian wan. Wuhan National Laboratory for Optoelectronics and School of Optical and Electronic Information Huazhong University of Science and TechnologyWuhan 430074China Optics Valley Laboratory Wuhan 430074China

In recent years,space-division multiplexing(SDM)technology,which involves transmitting data information on multiple parallel channels for efficient capacity scaling,has been widely used in fiber and free-space optical communication *** enable flexible data management and cope with the mixing between different channels,the integrated reconfig-urable optical processor is used for optical switching and mitigating the channel ***,efficient online train-ing becomes intricate and challenging,particularly when dealing with a significant number of *** we use the stochastic parallel gradient descent(SPGD)algorithm to configure the integrated optical processor,which has less com-putation than the traditional gradient descent(GD)*** design and fabricate a 6×6 on-chip optical processor on silicon platform to implement optical switching and descrambling assisted by the online training with the SPDG ***,we apply the on-chip processor configured by the SPGD algorithm to optical communications for optical switching and efficiently mitigating the channel crosstalk in SDM *** comparison with the traditional GD al-gorithm,it is found that the SPGD algorithm features better performance especially when the scale of matrix is large,which means it has the potential to optimize large-scale optical matrix computation acceleration chips.

关键词： optical communications optical signal processing channel descrambling optical neural network chip silicon photonics

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Design of High Performance MXene/Oxide Structure Memristors for Image Recognition Applications

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Chinese Journal of Electronics 2024年第2期33卷 336-345页

作者： Xiaojuan LIAN Yuelin SHI Xinyi shen.Xiang wan.Zhikuang CAI Lei wan. The College of Integrated Circuit Science and Engineering Nanjing University of Posts and Telecommunications The National and Local Joint Engineering Laboratory of RF Integration and Micro-Assembly Technology Nanjing University of Posts and Telecommunications

Recent popularity to realize image recognition by memristor-based neural network hardware systems has been witnessed owing to their similarities to neurons and ***,the stochastic formation of conductive filaments inside the oxide memristor devices inevitably makes them face some drawbacks,represented by relatively higher power consumption and severer resistance switching *** this work,we design and fabricate the Ag/MXene（Ti3C2）/SiO2/Pt memristor after considering the stronger interactions between Ti3C2and Ag ions,which lead to a Ti3C2/SiO2structure memristor owning to much lower "SET" voltage and smaller resistance switching fluctuation than pure ***,the conductances of the Ag/Ti3C2/SiO2/Pt memristor have been modulated by changing the number of the applied programming pulse,and two typical biological behaviors,i.e.,longterm potentiation and long-term depression,have been ***,device conductances are introduced into an integrated device-to-algorithm framework as synaptic weights,by which the MNIST hand-written digits are recognized with accuracy up to 77.39%.

关键词： Performance evaluation Silicon compounds Image recognition Power demand Memristors Switches Programming

A Simplified Method for the Stress Analysis of Underground Transfer Structures Crossing Multiple Subway Tunnels

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Computer Modeling in Engineering & Sciences 2024年第6期139卷 2893-2915页

作者： shen.yan.Dajiang Geng Ning Dai Mingjian Long Zhicheng Bai College of Civil Engineering Tongji UniversityShanghai200092China China Construction 4th Engineering Bureau 6th Corp. Ltd.Shanghai201199China Department of Civil and Architecture Engineering Hubei Polytechnic UniversityHuangshi435003China

According to the design specifications,the construction of extended piles involves traversing the tunnel’s upper region and extending to the underlying rock *** address this challenge,a subterranean transfer structure spanning multiple subway tunnels was *** on the function of piles in the transfer structure as springs with axial and bending stiffness,and taking into account the force balance and deformation coordination conditions of beams and plates within the transfer structure,we established a simplified mechanical model that incorporates soil stratification by combining it with the Winkler elastic foundation beam *** resolved established simplifiedmechanicalmodel employed finite difference technology and the Newton-Simpsonmethod,elucidating the mechanical mechanism of the transfer *** research findings suggest that the load carried by the upper structural columns can be transferred to the pile foundation beneath the beams through the transfer structure,subsequently reaching the deep soil layer and ensuring minimal impact on adjacent *** established simplified analysis method can be used for stress analysis of the transfer structure,concurrently considering soil stratification,pile foundation behavior,and plate *** pile length,pile section size,and beam section size within the transfer structure should account for the characteristics of the upper load,ensuring an even distribution of the beam bending moment.

关键词： Crossing tunnels transfer structure force mechanism simplify analysis layered soil mass

MUS Model:A Deep Learning-Based Architecture for IoT Intrusion Detection

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Computers, Materials & Continua 2024年第7期80卷 875-896页

作者： Yu yan.Yu yan. shen.Fang Minna Gao Yiding Chen College of Information Engineering University of Engineering of the Chinese People’s Armed Police Force(PAP)Xi’an710000China College of Missile Engineering Rocket Force Engineering UniversityXi’an710000China

In the face of the effective popularity of the Internet of Things(IoT),but the frequent occurrence of cybersecurity incidents,various cybersecurity protection means have been proposed and *** them,Intrusion Detection System(IDS)has been proven to be stable and ***,traditional intrusion detection methods have shortcomings such as lowdetection accuracy and inability to effectively identifymalicious *** address the above problems,this paper fully considers the superiority of deep learning models in processing highdimensional data,and reasonable data type conversion methods can extract deep features and detect classification using advanced computer vision techniques to improve classification *** TransformField(MTF)method is used to convert 1Dnetwork traffic data into 2D images,and then the converted 2D images are filtered by UnsharpMasking to enhance the image details by sharpening;to further improve the accuracy of data classification and detection,unlike using the existing high-performance baseline image classification models,a soft-voting integrated model,which integrates three deep learning models,MobileNet,VGGNet and ResNet,to finally obtain an effective IoT intrusion detection architecture:the MUS *** types of experiments are conducted on the publicly available intrusion detection dataset CICIDS2018 and the IoT network traffic dataset N_BaIoT,and the results demonstrate that the accuracy of attack traffic detection is greatly improved,which is not only applicable to the IoT intrusion detection environment,but also to different types of attacks and different network environments,which confirms the effectiveness of the work done.

关键词： Cyberspace security intrusion detection deep learning Markov Transition Fields(MTF) soft voting integration

Modulated symbol-based one-time pad secure transmission scheme using physical layer keys

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Science China(Information Sciences) 2024年第1期67卷 221-239页

作者： Xiaoyan.HU Zheng wan.Kaizhi HUANG Liang JIN Mengyao yan.Yajun CHEN Jinmei yan. Information Engineering University Purple Mountain Laboratories for Network and Communication Security

This paper proposes a novel modulated symbols-based one-time pad(SOTP) secure transmission scheme using physical layer *** classical physical layer key generation and exclusive OR(XOR)encryption in the discrete binary space,we design a framework for modulated symbols-based one-time pad(OTP) encryption,where the cryptographic primitive and mathematical model of SOTP is given to build a practical cryptographic *** with existing physical layer encryption(PLE) schemes,we provide rigorous proof that the framework can meet perfect secrecy and correctness *** addition,we provide a specific scheme of physical layer OTP secure transmission for quadrature amplitude modulation(QAM) and phase-shift keying(PSK) symbols based on physical layer *** scheme realizes the unification of bit encryption and symbol encryption,which can adaptively select the quantization level according to the signal-to-noise ratio(SNR) to minimize the symbol error rate(SER).Further,we analyze the performance quantitatively and derive the closed-form expressions of SER,which indicates that the proposed scheme has a lower ***,simulation results verify that the proposed symbol-wise OTP secure transmission scheme can achieve perfect secrecy and high reliability.

关键词： physical layer security one-time pad wireless channel physical layer encryption perfect secrecy

Prediction model for the initial seed clearing angles of a precision seed meter based on vector fields

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International Journal of Agricultural and Biological Engineering 2024年第2期17卷 140-148页

作者： wan.Jiao Junjie Zhang Xuhui Chen Hao shen.Yuxiang Huang Jiangtao Shi College of Mechanical and Electric Engineering Northwest A&F UniversityYangling 712100ShaanxiChina Xi’an YaAo Agricultural Machinery Ltd Xi’an 710300China

Seed clearing is a critical stage during precision seed metering process to ensure high seed ***,there is a lack of understanding of the dynamics in the seed clearing *** this study,a model was developed to predict initial seed clearing angle,in the seed clearing process using vector *** model was applied to an existing high-speed metering device and soybean seeds,and the model was evaluated with bench testing *** showed that dynamic changes in forces and constraints of seeds during the seed clearing process could be abstracted as vectors,and the changes of vector directions could be described by their phase *** phase angles were functions of the rotational angle of the seed *** phase angle of the constraint boundary linearly increases with the increase of the rotational *** phase angle of the force fluctuates,as the rotational angle *** seed clearing angle obtained from the phase angles varies from 8°to 59°,depending on the seeder travel *** comparing the values of the initial seed clearing angles predicted by the model with those from the bench tests,the root mean square error(RMSE)were from 2.73 to 3.14,and the correlation(r)between predict and observer were all higher than 0.98,indicating that the model had reasonably good accuracy.

关键词： mechanical precision seeder initial seed clearing angle prediction model vector fields high-speed photography technology