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An anonymous authentication and secure data transmission scheme for the Internet of Things based on blockchain

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Frontiers of Computer Science 2024年第3期18卷 183-197页

作者： Xingxing CHEN Qingfeng cheng Weidong YANG Xiangyang luo State Key Laboratory of Mathematical Engineering and Advanced Computing Zhengzhou Institute of Information Science and TechnologyZhengzhou 450001China Henan Key Laboratory of Grain Photoelectric Detection and Control Henan University of TechnologyZhengzhou 450001China Henan Province Key Laboratory of Cyberspace Situation Awareness Zhengzhou Institute of Information Science and TechnologyZhengzhou 450001China

With the widespread use of network infrastructures such as 5G and low-power wide-area networks,a large number of the Internet of Things(IoT)device nodes are connected to the network,generating massive amounts of ***,it is a great challenge to achieve anonymous authentication of IoT nodes and secure data *** present,blockchain technology is widely used in authentication and s data storage due to its decentralization and ***,Fan et *** a secure and efficient blockchain-based IoT authentication and data sharing *** studied it as one of the state-of-the-art protocols and found that this scheme does not consider the resistance to ephemeral secret compromise attacks and the anonymity of IoT *** overcome these security flaws,this paper proposes an enhanced authentication and data transmission scheme,which is verified by formal security proofs and informal security ***,Scyther is applied to prove the security of the proposed ***,it is demonstrated that the proposed scheme achieves better performance in terms of communication and computational cost compared to other related schemes.

关键词： Internet of Things blockchain authentication data transmission

Polyphenol-mediated interfacial deposition strategy for supported manganese oxide catalysts with excellent pollutant degradation performance

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Chinese Chemical Letters 2024年第5期35卷 493-498页

作者： Dong cheng Youyou Feng Bingxi Feng Ke Wang Guoxin Song gen Wang Xiaoli cheng Yonghui Deng Jing Wei The Key Laboratory of Biomedical Information Engineering of Ministry of Education State Key Lab of Transducer TechnologySchool of Life Science and TechnologyXi’an Jiaotong UniversityXi’an 710049China School of Environmental and Municipal Engineering Xi’an University of Architecture and TechnologyXi’an 710055China Department of Chemistry State Key Laboratory of Molecular Engineering of PolymersState Key Laboratory of Transducer TechnologyFudan UniversityShanghai 200433China Key Laboratory of Functional Inorganic Material Chemistry Ministry of EducationSchool of Chemistry and Materials ScienceHeilongjiang UniversityHarbin 150080China

In persulfate-based advanced oxidation process(PS-AOPs),fixing nanosized metal oxide on processable substrates is highly desirable to avoid the aggregation and loss of nanocatalysts during the practical ***,it is still challenging to develop a versatile strategy for the deposition of metal oxide nanocatalysts on various substrates with different physicochemical ***,polyphenols are utilized as a“molecular glue”and reductant to mediate the interfacial deposition of MnO_(2) nanocatalysts on different ***_(2) nanocatalysts were in-situ grown on macroscope mineral substrates(e.g.,airstone)via an interfacial redox strategy between tannic acid(TA)and oxidized KMnO4,and then employed as a fixed catalyst of peroxymonosulfate(PMS)activation for treating pharmaceutical and personal care products(PPCPs)in *** fixed MnO_(2) exhibited superior catalytic performance toward different PPCPS via a singlet oxygen(^(1)O_(2))-dominated nonradical oxidation *** in the secondary effluent of wastewater treatment plants could be effectively removed by a fixed-bed column of the fixed MnO_(2) with long term *** cycle of Mn^(4+)/Mn^(3+)and surface hydroxyl group of the fixed MnO_(2) was proved to be responsible for the activation of *** work provides a new avenue for developing fixed metal oxides for sustainable water treatment.

关键词： Redox strategy Manganese oxides Fixed catalyst Peroxymonosulfate PPCPs

Influences of shale microstructure on mechanical properties and bedding fractures distribution

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Petroleum Science 2024年第3期21卷 1944-1954页

作者： Ming-Zhe Gu Mao Sheng Shi-Zhong cheng Fan-Hao Gong gen-Sheng Li State Key Laboratory of Petroleum Resources and Engineering China University of Petroleum-Beijing College of Petroleum Engineering China University of Petroleum-Beijing Shenyang Center of China Geological Survey

The difference in microstructure leads to the diversity of shale mechanical properties and bedding fractures distribution patterns. In this paper, the microstructure and mechanical properties of Longmaxi marine shale and Qingshankou continental shale were studied by X-ray diffractometer(XRD), field emission scanning electron microscope(FE-SEM) with mineral analysis system, and ***, the typical bedding layers area was properly stratified using Focused Ion Beam(FIB), and the effects of microstructure and mechanical properties on the distribution patterns of bedding fractures were analyzed. The results show that the Longmaxi marine shale sample contains more clay mineral grains, while the Qingshankou continental shale sample contains more hard brittle mineral grains such as feldspar. For Longmaxi marine shale sample, hard brittle minerals with grain sizes larger than 20 μm is18.24% and those with grain sizes smaller than 20 μm is 16.22%. For Qingshankou continental shale sample, hard brittle minerals with grain sizes larger than 20 μm is 40.7% and those with grain sizes smaller than 20 μm is 11.82%. In comparison to the Qingshankou continental shale sample, the Longmaxi marine shale sample has a lower modulus, hardness, and heterogeneity. Laminated shales are formed by alternating coarse-grained and fine-grained layers during deposition. The average single-layer thickness of Longmaxi marine shale sample is greater than Qingshankou continental shale sample. The two types of shale have similar bedding fractures distribution patterns and fractures tend to occur in the transition zone from coarse-grained to fine-grained deposition. The orientation of the fracture is usually parallel to the bedding plane and detour occurs in the presence of hard brittle grains. The fracture distribution density of the Longmaxi marine shale sample is lower than that of the Qingshankou continental shale sample due to the strong heterogeneity of the Qingshankou contine

关键词： Shale Nanoindentation Microstructure Mechanical property Fracture

CO_(2)flooding in shale oil reservoir with radial borehole fracturing for CO_(2)storage and enhanced oil recovery

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Petroleum Science 2024年第1期21卷 519-534页

作者： Jia-cheng Dai Tian-Yu Wang Jin-Tao Weng Kang-Jian Tian Li-Ying Zhu gen-Sheng Li State Key Laboratory of Petroleum Resources and Prospecting China University of PetroleumBeijing102249China China National Oil and Gas Exploration and Development Company Limited Beijing100034China

This study introduces a novel method integrating CO_(2)flooding with radial borehole fracturing for enhanced oil recovery and CO_(2)underground storage,a solution to the limited vertical stimulation reservoir volume in horizontal well fracturing.A numerical model is established to investigate the production rate,reservoir pressure field,and CO_(2)saturation distribution corresponding to changing time of CO_(2)flooding with radial borehole fracturing.A sensitivity analysis on the influence of CO_(2)injection location,layer spacing,pressure difference,borehole number,and hydraulic fractures on oil production and CO_(2)storage is *** CO_(2)flooding process is divided into four *** in layer spacing will significantly improve oil production rate and gas storage ***,serious gas channeling can occur when the spacing is lower than 20 *** the pressure difference between the producer and injector,the borehole number,the hydraulic fracture height,and the fracture width can also increase the oil production rate and gas storage *** analysis shows that layer spacing and fracture height greatly influence gas storage and oil *** outcomes are expected to provide a theoretical basis for the efficient development of shale oil reservoirs in the vertical direction.

关键词： Shale oil Radial borehole fracturing Embedded discrete fracture model Enhanced oil recovery Carbon storage

Shape optimisation of basin insulator for DC gas insulated switchgear/gas insulated transmission lines based on artificial bee colony algorithm

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High Voltage 2024年第2期9卷 275-286页

作者： Yi luo Shiyi Mao Ju Tang Zijun Pan cheng Pan State Key Laboratory of Power Grid Environmental Protection School of Electrical Engineering and AutomationWuhan UniversityWuhanChina

The surface charge accumulation on the basin insulator is a particular problem in high-voltage direct current(HVDC)gas insulated switchgears(GIS)and gas insulated trans-mission lines(GIL),which restricts the development and application of extra/ultra high-voltage(EHV/UHV)*** surface charge distribution and anti-flashover performance are closely related to the insulator *** obtain the optimal basin insulator,a shape optimisation model based on artificial bee colony algorithm was established,and the minimisation objective functions based on capacitive(initial)electric field distribution and resistive(steady-state)electric field distribution were respectively *** optimisation results of the two objective functions were calculated,and the electric field and charge distribution on the surface of the insulator before and after optimisation were evaluated and compared using the simulation *** results indicated that the optimisation based on the capacitive electric field can significantly inhibit the surface charge accumulation,and the optimised insulator can significantly reduce the surface normal electric field and make the distribution of the tangential electric field more uniform,and the maximum tangential electric field can be reduced by 10%;the optimisation based on resistive electric field can achieve similar results,but requires more computational *** on the results,the‘anti-charge’basin insulator structure suitable for the DC field was given.

关键词： insulator artificial charge

Segment differential aggregation representation and supervised compensation learning of ConvNets for human action recognition

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Science China(Technological Sciences) 2024年第1期67卷 197-208页

作者： REN ZiLiang ZHANG QieShi cheng Qin XU ZhenYu YUAN Shuai luo DeLin School of Computer Science and Technology Dongguan University of TechnologyDongguan 523808China Shenzhen Institute of Advanced Technology Chinese Academy of SciencesShenzhen 518055China School of Electronic Engineering and Automation Guilin University of Electronic TechnologyGuilin 541004China Department of the mechanical engineering Erlangen-Nuremberg UniversityErlangen 91508Germany School of Aerospace Engineering Xiamen UniversityXiamen 361102China

With more multi-modal data available for visual classification tasks,human action recognition has become an increasingly attractive ***,one of the main challenges is to effectively extract complementary features from different modalities for action *** this work,a novel multimodal supervised learning framework based on convolution neural networks(Conv Nets)is proposed to facilitate extracting the compensation features from different modalities for human action *** on information aggregation mechanism and deep Conv Nets,our recognition framework represents spatial-temporal information from the base modalities by a designed frame difference aggregation spatial-temporal module(FDA-STM),that the networks bridges information from skeleton data through a multimodal supervised compensation block(SCB)to supervise the extraction of compensation *** evaluate the proposed recognition framework on three human action datasets,including NTU RGB+D 60,NTU RGB+D 120,and *** results demonstrate that our model with FDA-STM and SCB achieves the state-of-the-art recognition performance on three benchmark datasets.

关键词： action recognition segment frame difference aggregation supervised compensation learning ConvNets

Influence of meteorological factors on open biomass burning at a background site in Northeast China

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Journal of Environmental Sciences 2024年第4期138卷 1-9页

作者： Yulong Wang Linlin Liang Wanyun Xu Chang Liu Hongbing cheng Yusi Liu gen Zhang Xiaobin Xu Dajiang Yu Peng Wang Qingli Song Jiumeng Liu Yuan cheng State Key Laboratory of Urban Water Resource and Environment School of EnvironmentHarbin Institute of TechnologyHarbin 150090China State Key Laboratory of Severe Weather&Key Laboratory for Atmospheric Chemistry Chinese Academy of Meteorological SciencesBeijing 100081China Longfengshan Regional Background Station China Meteorological AdministrationHeilongjiang 150200China Heilongjiang Climate Center Heilongjiang 150030China

Biomass burning(BB)is a very important emission source that significantly adversely impacts regional air *** produces a large number of primary organic aerosol(POA)and black carbon(BC).Besides,BB also provides many precursors for secondary organic aerosol(SOA)*** this work,the ratio of levoglucosan(LG)to organic carbon(OC)and the fire hotspots map was used to identify the open biomass burning(OBB)events,which occurred in two representative episodes,October 13 to November 30,2020,and April1 to April 30,*** ratio of organic aerosol(OA)to reconstructed PM_(2.5)concentration(PM_(2.5)^(*))increased with the increase of LG/*** LG/OC ratio is higher than 0.03,the highest OA/PM_(2.5)^(*)ratio can reach 80%,which means the contribution of OBB to OA is *** to the ratio of LG to K^(+),LG to mannosan(MN)and the regional characteristics of Longfengshan,it can be determined that the crop residuals are the main *** occurrence of OBB coincides with farmers’preferred choices,i.e.,burning biomass in“bright weather”.The“bright weather”refers to the meteorological conditions with high temperature,low humidity,and without *** factors indirectly affect regional biomass combustion pollution by influencing farmers’active choices.

关键词： Air pollution Biomass burning Meteorological factors Organic trace Agricultural fires

Impact of next-generation sequencing on antimicrobial treatment in immunocompromised adults with suspected infections

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World Journal of Emergency Medicine 2024年第2期15卷 105-110页

作者： Jia Li Jiazhen luo Tao Hu Ling cheng Weiwei Shang Li Yan Department of Intensive Care Unit Tongji HospitalTongji Medical CollegeHuazhong University of Science and TechnologyWuhan 430030China Department of Emergency Medicine Tongji HospitalTongji Medical CollegeHuazhong University of Science and TechnologyWuhan 430030China Tongji Medical College Huazhong University of Science and TechnologyWuhan 430030China Department of Geriatrics Tongji HospitalTongji Medical CollegeHuazhong University of Science and TechnologyWuhan 430030China

BACKGROUND:Prompt pathogen identification can have a substantial impact on the optimization of antimicrobial *** objective of the study was to assess the diagnostic value of next-generation sequencing(NGS)for identifying pathogen and its clinical impact on antimicrobial intervention in immunocompromised patients with suspected ***:This was a retrospective *** January and August 2020,47 adult immunocompromised patients underwent NGS testing under the following clinical conditions:1)prolonged fever and negative conventional cultures;2)new-onset fever despite empiric antimicrobial treatment;and 3)afebrile with suspected infections on *** data,including conventional microbial test results and antimicrobial treatment before and after NGS,were *** were analyzed according to documented changes in antimicrobial treatment(escalated,no change,or deescalated)after the NGS ***:The median time from hospitalization to NGS sampling was 19 *** relevant pathogens were detected via NGS in 61.7% of patients(29/47),more than half of whom suffered from fungemia(n=17),resulting in an antimicrobial escalation in 53.2% of patients(25/47)and antimicrobial de-escalation in 0.2% of patients(1/47).Antimicrobial changes were mostly due to the identification of fastidious organisms such as Legionella,Pneumocystis jirovecii,and *** the remaining three cases,NGS detected clinically relevant pathogens also detected by conventional cultures a few days *** antimicrobial treatment was subsequently adjusted according to the susceptibility test ***,NGS changed antimicrobial management in 55.3%(26/47)of patients,and conventional culture detected clinically relevant pathogens in 14.9% of the patients(7/47).CONCLUSION:With its rapid identification and high sensitivity,NGS could be a promising tool for identifying relevant pathogens and enabling rapid appropriate treatment in immunocompromised patients w

关键词： Immunocompromised patients Next-generation sequencing Antimicrobial management

Defects in the grain interiors of 3 mol%yttria-stabilized tetragonal zirconia polycrystal ceramics with 0.25 wt%alumina

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Journal of Advanced Ceramics 2024年第4期13卷 469-477页

作者： Yan Xiong Lian luo Yao cheng Zhi Liu Qi Liu Weimin Wang Wei Ji School of Materials&Chemical Engineering Hubei Province Key Laboratory of Green Materials for Light IndustryHubei University of TechnologyWuhan 430068China Fujian Institute of Research on the Structure of Mater Chinese Academy of SciencesFuzhou 350002China Jiangxi Provincial Engineering Research Center for Multifunction Zirconia Materials Jiangxi Size Materials Co.Ltd.Jiujiang 332500China State Key Laboratory of Advance Technology for Materials Synthesis and Processing Wuhan University of TechnologyWuhan 430070China

The presence of high-density defects is rarely observed in bulk 3 mol%yttria-stabilized tetragonal zirconia polycrystal(3Y-TZP)ceramics obtained through conventional pressureless *** the present work,fine-grained dense 147 nm 3Y-TZP ceramics were prepared by pressureless sintering of commercial 0.25 wt%alumina-doped zirconia powders at 1300℃.A novel discovery was reported in which large amounts of defects were present in the grain interiors of the *** phenomenon was further examined using three types of powder samples,and the reasons for defect formation were investigated by microstructural characterization using high-resolution transmission electron microscopy(HRTEM)analysis and Rietveld *** results confirmed the essential dependence of the defect formation on the alumina *** authors attributed the defect formation to the significant difference in ionic radii of the solvent and solute during the dissolution of alumina into the zirconia *** sintering kinetics were proposed to be enhanced by the presence of substantial defects,which consequently favored the low-temperature sintering of the alumina-doped zirconia ceramics.

关键词： 3 mol%yttria-stabilized tetragonal zirconia polycrystal(3Y-TzP)ceramics alumina addition microstructure defect