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Secure intelligent reflecting surface assisted mobile edge computing system with wireless power transfer

Digital Communications and Networks 2024年第6期10卷 1874-1880页

作者： Dawei Wang Xuanrui Li Menghan Wu Yixin He Yi Lou Yu Pang Yi Lu School of Electronics and Information Northwestern Polytechnical UniversityXi'an 710072China College of Information Science and Engineering Jiaxing UniversityJiaxing 314001China Jiaxing Key Laboratory of Smart Transportations Jiaxing UniversityJiaxing 314001China College of Information Science and Engineering Harbin Institute of Technology(Weihai)Weihai 264209China Chongqing Key Laboratory of Photoelectronic Information Sensing and Transmitting Technology School of Optoelectronic EngineeringChongqing University of Posts and TelecommunicationsChongqing 400065China

In this paper,we study an Intelligent Reflecting Surface(IRS)assisted Mobile Edge Computing(MEC)system under eavesdropping threats,where the IRS is used to enhance the energy signal transmission and the offloading performance between Wireless Devices(WDs)and the Access Point(AP).Specifically,in the proposed scheme,the AP first powers all WDs with the wireless power transfer through both direct and IRS-assisted ***,powered by the harvested energy,all WDs securely offload their computation tasks through the two links in the time division multiple access *** determine the local and offloading computational bits,we formulate an optimization problem to jointly design the IRS's phase shift and allocate the time slots constrained by the security and energy *** cope with this non-convex optimization problem,we adopt semidefinite relaxations,singular value decomposition techniques,and Lagrange dual ***,we propose a dichotomy particle swarm algorithm based on the bisection method to process the overall optimization problem and improve the convergence *** numerical results illustrate that the proposed scheme can boost the performance of MEC and secure computation rates compared with other IRS-assisted MEC benchmark schemes.

关键词： Intelligent reflecting surface Mobile edge computing Power transfer Information security

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A Few-Shot Learning-Based Automatic Modulation Classification Method for Internet of Things

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china Communications 2024年第8期21卷 18-29页

作者： Aer Sileng Qi Chenhao School of Information Science and Engineering Southeast UniversityNanjing 210096China

Due to the limited computational capability and the diversity of the Internet of Things devices working in different environment,we consider fewshot learning-based automatic modulation classification(AMC)to improve its reliability.A data enhancement module(DEM)is designed by a convolutional layer to supplement frequency-domain information as well as providing nonlinear mapping that is beneficial for *** network is designed to have multiple residual blocks,where each residual block has multiple convolutional kernels of different sizes for diverse feature ***,a deep supervised loss function is designed to supervise all parts of the network including the hidden layers and the *** different model may output different results,cooperative classifier is designed to avoid the randomness of single model and improve the *** results show that this few-shot learning-based AMC method can significantly improve the AMC accuracy compared to the existing methods.

关键词： automatic modulation classification(AMC) deep learning(DL) few-shot learning Internet of Things(IoT)

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2D Undulated Metal Hydrogen-Bonded Organic Frameworks with Self-Adaption Interlayered Sites for Highly Efficient C-C Coupling in the Electrocatalytic CO2 Reduction

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纳微快报（英文版） 2025年第7期17卷 223-233页

作者： Jianning Lv Wenrui Li Shuai Li Shuo Xu Zunhang Lv Zhejiaji Zhu Lu Dai Bo Wang Pengfei Li Key Laboratory of Cluster Science Ministry of Education Beijing Key Laboratory of Photoelectronic/ElectrophotonicSchool of Chemistry and Chemical EngineeringBeijing Institute of TechnologyBeijing 100081People's Republic of China Key Laboratory of Cluster Science Ministry of Education Beijing Key Laboratory of Photoelectronic/ElectrophotonicSchool of Chemistry and Chemical EngineeringBeijing Institute of TechnologyBeijing 100081People's Republic of China Petrochina Petrochemical Research Institute Beijing 102206People's Republic of China Key Laboratory of Cluster Science Ministry of Education Beijing Key Laboratory of Photoelectronic/ElectrophotonicSchool of Chemistry and Chemical EngineeringBeijing Institute of TechnologyBeijing 100081People's Republic of China Advanced Technology Research Institute(Ji'nan) Beijing Institute of TechnologyJi'nan 250300People's Republic of China Key Laboratory of Cluster Science Ministry of Education Beijing Key Laboratory of Photoelectronic/ElectrophotonicSchool of Chemistry and Chemical EngineeringBeijing Institute of TechnologyBeijing 100081People's Republic of China Advanced Research Institute of Multidisciplinary Science Beijing Institute of Technology(Zhuhai)Zhuhai 519088People's Republic of China

The hydrogen-bonded organic frameworks(HOFs)as a new type of porous frame-work materials have been widely studied in vari-ous ***,the lack of appropriate active sites,low intrinsic conductivity,and poor stability limited their performance in the field of ***,we designed two 2D metal hydro-gen-bonded organic frameworks(2D-M-HOF,M=Cu2+or Ni2+)with coordination compounds based on 2,3,6,7,14,15-hexahydroxyl cyclotricat-echylene and transition metalions(Cu2+and Ni2+),*** crystal structure of 2D-Cu-HOF is determined by continuous rotation electron dif-fraction,indicating an undulated 2D hydrogen-bond network with interlayeredπ-π *** flexible structure of 2D-M-HOF leads to the formation of self-adaption interlayered sites,resulting in superior activity and selectivity in the electrocatalytic conversion of CO2 to C2 products,achieving a total Faradaic efficiency exceeding 80％due to the high-efficiency C-C *** experimental results and density functional calculations verify that the undulated 2D-M-HOF enables the energetically favorable formation of*OCCHO *** work provides a promising strategy for designing HOF catalysts in electrocatalysis and related processes.

关键词： Hydrogen-bonded organic frameworks Flexible structure Self-adaption interlayered sites Electrocatalytic CO2 reduction

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Incorporation of Mg-phenolic networks as a protective coating for magnesium alloy to enhance corrosion resistance and osteogenesis in vivo

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Journal of Magnesium and Alloys 2023年第11期11卷 4247-4262页

作者： Chang Wang Bo Zhang Sen Yu Hao Zhang Wenhao Zhou Rifang Luo Yunbing Wang Weiguo Bian Genwen Mao Shaanxi Key Laboratory of Biomedical Metallic Materials Northwest Institute for Non-ferrous Metal ResearchXi’anShaanxi 710016China School of Materials Science and Engineering Northwestern Polytechnical UniversityXi’anShaanxi 710072China National Engineering Research Center for Biomaterials Sichuan UniversityChengduSichuan 610065China Department of Orthopedics The First Affiliated Hospital of Xi’an Jiaotong UniversityXi’anShaanxi 710061China Department of Orthopedics The Second Affiliated Hospital of Xi’an Jiaotong UniversityXi’anShaanxi 710004China

Magnesium(Mg) and its alloys have been intensively studied to develop the next generation of bone implants recently, but their clinical application is restricted by rapid degradation and unsatisfied osteogenic effect in vivo. A bioactive chemical conversion Mg-phenolic networks complex coating(e EGCG) was stepwise incorporated by epigallocatechin-3-gallate(EGCG) and exogenous Mg^(2+)on Mg-2Zn magnesium alloy. Simplex EGCG induced chemical conversion coating(c EGCG) was set as compare group. The in vitro corrosion behavior of Mg-2Zn alloy, c EGCG and e EGCG was evaluated in SBF using electrochemical(PDP, EIS) and immersion test. The cytocompatibility was investigated with rat bone marrow mesenchymal stem cells(r BMSCs). Furthermore, the in vivo tests using a rabbit model involved micro computed tomography(Micro-CT) analysis, histological observation, and interface analysis. The results showed that the e EGCG is Mgphenolic multilayer coating incorporated Mg-phenolic networks, which is rougher, more compact and much thicker than c EGCG. The e EGCG highly improved the corrosion resistance of Mg-2Zn alloy, combined with its lower average hemolytic ratios, continuous high scavenging effect ability and relatively moderate contact angle features, resulting in a stable and suitable biological environment, obviously promoted r BMSCs adhesion and proliferation. More importantly, Micro-CT, histological and interface elements distribution evaluations all revealed that the e EGCG effectively inhibited degradation and enhanced bone tissue formation of Mg alloy implants. This study puts forward a promising bioactive chemical conversion coating with Mg-phenolic networks for the application of biodegradable orthopedic implants.

关键词： Mg-phenolic networks Bioactive coating Mg-2Zn alloy Corrosion resistance Osteogenesis

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Defect engineering and Ni promoter synergistically accelerating electron transfer to Ru^(0) sites in UiO-66(Ce) for dicyclopentadiene hydrogenation under mild condition

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Nano research 2024年第11期17卷 9550-9563页

作者： Rushuo Li Tao Ban Danfeng Zhao Jing Lin Zhiyuan Liu Linmeng Wang Xiubing Huang Zhiping Tao Ge Wang Beijing Advanced Innovation Center for Materials Genome Engineering Beijing Key Laboratory of Function Materials for Molecule and Structure Construction School of Materials Science and Engineering University of Science and Technology Beijing Beijing 100083 China Sinopec Research Institute of Petroleum Processing Co. Ltd. Beijing 100083 China

Olefin hydrogenation under mild condition is crucial and challenging for industrial applications. Herein, defective UiO-66(Ce) was constructed by using cyanuric acid as the molecular etching “scissors” and further to synthesize heterogeneous catalyst with highly dispersed RuNi nanoparticles (Ru1Ni1.5@UiO-66(Ce)-12 h). The construction of Ce-O-Ru/Ni heterogeneous interfaces and Ni–Ru bonds provide electron transfer channels from Ce-oxo clusters and Ni species to Ru species. Furthermore, the microenvironment and electronic structure of Ru0 active sites were synergistically regulated by adjusting the content of metal-organic frameworks (MOFs) defects and Ni promoter, thereby enhancing the adsorption and activation ability of H–H and C=C bonds. Therefore, Ru1Ni1.5@UiO-66(Ce)-12 h achieved dicyclopentadiene saturated hydrogenation (100% conversion) to tetrahydrodicyclopentadiene (∼ 100% selectivity) under mild condition (35℃, 1 MPa) with only 25 min. Meanwhile, the sample exhibited excellent structural stability after 6 cycles test. This study provides a promising strategy for the rational design of remarkable noble metal-based catalysts for practical applications.

关键词： metal-organic frameworks defect engineering Ni promoter electron-rich Ru^(0)active sites dicyclopentadiene hydrogenation

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Molecular dynamics exploration of the barrier properties of small gas molecules in the semicrystalline parylene C

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PHYSICAL CHEMISTRY CHEMICAL PHYSICS 2025年第17期27卷 8868-8877页

作者： Li, Shuo Xue, Zhiyu Wang, Xin Xu, Dingguo Sichuan Univ Coll Chem MOE Key Lab Green Chem & Technol Chengdu 610064 Sichuan Peoples R China Univ Elect Sci & Technol China Sch Mat & Energy Chengdu 611731 Peoples R China

Poly(chloro-p-xylylene) (parylene C) is recognized for its outstanding chemical resistance, high thermal stability, biocompatibility, and superior permeability barrier properties. This material predominantly exists in a semicrystalline state. Despite its significance, theoretical studies simulating the semicrystalline parylene C system are scarce. This study aims to elucidate the relationship between the semicrystalline structures and the barrier properties of parylene C through a molecular dynamics approach. Semicrystalline parylene C with 10-50% aligned regions were constructed, which exhibited a degree of crystallinity ranging from 17% to 44%. We discovered that increased aligned chains could significantly alter the material's structure and morphology. These changes could further lead to variations in the density, fractional free volume, and pore size distribution of parylene C, thus affecting its glass transition temperature, permeability barrier and mechanical properties. Additionally, the relative values of gas permeability coefficients closely match experimental data. The insights into the structure-property relationship presented in this work could offer valuable guidance for developing functionalized and structured parylene C as coating materials.

关键词： Molecular dynamics

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TENSOR NEURAL NETWORK AND ITS NUMERICAL INTEGRATION

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Journal of Computational Mathematics 2024年第6期42卷 1714-1742页

作者： Yifan Wang Hehu Xie Pengzhan Jin LSEC NCMISInstitute of Computational MathematicsAcademy of Mathematics and Systems ScienceChinese Academy of SciencesBeijing 100190China School of Mathematical Sciences University of Chinese Academy of SciencesBeijing 100049China School of Mathematical Sciences Peking UniversityBeijing 100871China

In this paper,we introduce a type of tensor neural *** the first time,we propose its numerical integration scheme and prove the computational complexity to be the polynomial scale of the *** on the tensor product structure,we develop an efficient numerical integration method by using fixed quadrature points for the functions of the tensor neural *** corresponding machine learning method is also introduced for solving high-dimensional *** numerical examples are also provided to validate the theoretical results and the numerical algorithm.

关键词： Tensor neural network Numerical integration Fixed quadrature points Machine learning High-dimensional eigenvalue problem

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Dual-plasticizer intermolecular interaction engineering in CO_(2)-based quasi-solid-state polymer electrolytes addressing high-performance lithium metal batteries

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Journal of Energy Chemistry 2025年第4期103卷 803-812页

作者： Gang Su Maoning Geng Lei Zhong Min Xiao Shuanjin Wang Sheng Huang Hui Guo Dongmei Han Yuezhong Meng School of Chemical Engineering and Technology Sun Yat-sen UniversityGuangzhou 510275GuangdongChina The Key Laboratory of Low-Carbon Chemistry&Energy Conservation of Guangdong Province/State Key Laboratory of Optoelectronic Materials and Technologies School of Materials Science and EngineeringSun Yat-sen UniversityGuangzhou 510275GuangdongChina Institute of Chemistry Henan Academy of SciencesZhengzhou 450000HenanChina College of Chemistry Zhengzhou UniversityZhengzhou 450001HenanChina

One effective approach to strike the balance between ionic conductivity and mechanical strength in polymer electrolytes involves the design of a coupled polymer molecular structure comprising both rigid and flexible ***,the regulation of intermolecular interactions between plasticizers and rigid and flexible phases has been largely ***,an intermolecular interaction engineering strategy is carried out with well-chosen dual-plasticize within qua si-sol id-state polymer electrolytes(QSPEs).Succinonitrile exhibits a stronger affinity towards rigid phase hydrogenated nitrile butadiene rubber(HNBR),while propene carbonate demonstrates a stronger affinity towards flexible segments poly(propylene carbonate)(PPC).This tailored intermolecular interaction engineering allows for differential plasticization of the polymer's rigid and flexible phases,thereby achieving a balance between ionic conductivity and mechanical *** QSPE have both higher ionic conductivity(1.04×10^(-4)S cm^(-1)at 30℃),t_(Li+)(0.55),and tensile strength(0.76 MPa).Li//Li symmetric cells maintaining performance over1100 h at 0.1 mA cm^(-2)and Li//LiFePO_(4)cells retaining 85.0%capacity after 700 cycles at 1.0 *** is a unique angle to employ intermolecular interaction engineering in QSPEs through dual-plasticizer approach combined with CO_(2)-based polymer *** sustainable strategy combining dual-plasticizer engineering with CO_(2)-based polymers,offers insights for designing high-performance,eco-friendly lithium metal batteries.

关键词： Quasi-solid-state polymer electrolytes Intermolecular interaction engineering Similarity and intermiscibility Lithium metal batteries

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Experimental investigation of the microscopic interaction mechanism between sand and tall fescue roots by using X-ray microtomography

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ACTA GEOTECHNICA 2024年第3期19卷 1529-1554页

作者： Wang, Ji-Peng Sha, Jun-Feng Gao, Xu-Guang Dadda, Abdelali Qi, Meng Ge, Shangqi Shandong Univ Sch Civil Engn Jingshi Rd 17922 Jinan 250061 Peoples R China Yalong River Hydropower Dev Co Ltd Shuanglin Rd 288 Chengdu 610051 Peoples R China

This study aimed to enhance the understanding of root-soil interaction at a microscale level and its implications for practical land management, ecosystem restoration, and engineered solutions on vegetated slopes. Specifically, the interaction between tall fescue roots and sand was investigated using four-dimensional (4D) CT scanning. The growth process of tall fescue roots in sand was tracked on the 2nd, 4th, 6th, and 8th days after seed transplantation. To accurately segment root-soil CT images and overcome challenges such as the partial volume effect (PVE) and the similarity of root water grayscale in CT images, a semiautomatic segmentation process was employed. The analysis focused on examining the evolution of three-dimensional root parameters throughout the growth process. The findings highlighted the significant influence of initial porosity on tall fescue root development, the global decrease in saturation with root growth, and the predominant impact of pore distribution on local saturation distribution. The study revealed that the root system's influence on saturation, on the eighth day after transplantation, extended up to 800 pixels (8 mm) from the root surface. These results have practical implications for optimizing planting density and providing effective planting strategies for vegetated slope design in engineering applications.

关键词： Image segmentation Representative volume element Root-soil interaction X-ray computed tomography

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Environment and COVID-19 incidence: A critical review

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Journal of Environmental Sciences 2023年第2期124卷 933-951页

作者： Jiatong Han Jie Yin Xiaoxu Wu Danyang Wang Chenlu Li State Key Laboratory of Remote Sensing Science College of Global Change and Earth System ScienceBeijing Normal UniversityBeijing 100875China

The coronavirus disease 2019(COVID-19)pandemic is an unprecedented worldwide health *** previous research studies have found and investigated its links with one or some natural or human environmental ***,a review on the relationship between COVID-19 incidence and both the natural and human environment is still *** review summarizes the inter-correlation between COVID-19 incidence and environmental *** on keyword searching,we reviewed 100 relevant peer-reviewed articles and other research literature published since January *** review is focused on three main ***,we found that individual environmental factors have impacts on COVID-19 incidence,but with spatial heterogeneity and ***,environmental factors exert interactive effects on COVID-19 *** particular,the interactions of natural factors can affect COVID-19 transmission in micro-and macro-ways by impacting SARS-CoV-2 survival,as well as human mobility and ***,the impact of COVID-19 incidence on the environment lies in the fact that COVID-19-induced lockdowns caused air quality improvement,wildlife shifts and socio-economic *** additional value of this review is that we recommend future research perspectives and adaptation strategies regarding the interactions of the environment and *** research should be extended to cover both the effects of the environment on the COVID-19 pandemic and COVID-19-induced impacts on the *** adaptation strategies should focus on sustainable environmental and public policy responses.

关键词： COVID-19 Natural environment Human environment Interaction

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