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Working condition recognition of sucker rod pumping system based on 4-segment time-frequency signature matrix and deep learning

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Petroleum Science 2024年第1期21卷 641-653页

作者： Yun-Peng He Hai-Bo Cheng Peng zeng Chuan-Zhi Zang Qing-Wei Dong Guang-Xi wan Xiao-ting Dong State Key Laboratory of Robotics Shenyang Institute of AutomationChinese Academy of SciencesShenyang 110016LiaoningChina Key Laboratory of Networked Control Systems Chinese Academy of SciencesShenyang 110016LiaoningChina Institutes for Robotics and Intelligent Manufacturing Chinese Academy of SciencesShenyang 110169LiaoningChina University of Chinese Academy of Sciences Beijing100049China School of Artifcial Intelligence Shenyang University of TechnologyShenyang 110870LiaoningChina

High-precision and real-time diagnosis of sucker rod pumping system(SRPS)is important for quickly mastering oil well *** learning-based method for classifying the dynamometer card(DC)of oil wells is an efficient diagnosis ***,the input of the DC as a two-dimensional image into the deep learning framework suffers from low feature utilization and high computational ***,different SRPSs in an oil field have various system parameters,and the same SRPS generates different DCs at different ***,there is heterogeneity in field data,which can dramatically impair the diagnostic *** solve the above problems,a working condition recognition method based on 4-segment time-frequency signature matrix(4S-TFSM)and deep learning is presented in this ***,the 4-segment time-frequency signature(4S-TFS)method that can reduce the computing power requirements is proposed for feature extraction of DC ***,the 4S-TFSM is constructed by relative normalization and matrix calculation to synthesize the features of multiple data and solve the problem of data ***,a convolutional neural network(CNN),one of the deep learning frameworks,is used to determine the functioning conditions based on the *** on field data verify that the proposed diagnostic method based on 4S-TFSM and CNN(4S-TFSM-CNN)can significantly improve the accuracy of working condition recognition with lower computational *** the best of our knowledge,this is the first work to discuss the effect of data heterogeneity on the working condition recognition performance of SRPS.

关键词： Sucker-rod pumping system Dynamometer card Working condition recognition Deep learning Time-frequency signature Time-frequency signature matrix

Heterogeneous Task Allocation Model and Algorithm for Intelligent Connected Vehicles

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Computers, Materials & Continua 2024年第9期80卷 4281-4302页

作者： Neng wan Guangping zeng Xianwei Zhou School of Computer and Communication Engineering University of Science and Technology BeijingBeijing100083China School of Mechanical and Transportation Southwest Forestry UniversityKunming650224China

With the development of vehicles towards intelligence and connectivity,vehicular data is diversifying and growing dramatically.A task allocation model and algorithm for heterogeneous Intelligent Connected Vehicle(ICV)applications are proposed for the dispersed computing network composed of heterogeneous task vehicles and Network Computing Points(NCPs).Considering the amount of task data and the idle resources of NCPs,a computing resource scheduling model for NCPs is *** the heterogeneous task execution delay threshold as a constraint,the optimization problem is described as the problem of maximizing the utilization of computing resources by *** proposed problem is proven to be NP-hard by using the method of reduction to a 0-1 knapsack problem.A many-to-many matching algorithm based on resource preferences is *** algorithm first establishes the mutual preference lists based on the adaptability of the task requirements and the resources provided by *** enables the filtering out of un-schedulable NCPs in the initial stage of matching,reducing the solution space *** solve the matching problem between ICVs and NCPs,a new manyto-many matching algorithm is proposed to obtain a unique and stable optimal matching *** simulation results demonstrate that the proposed scheme can improve the resource utilization of NCPs by an average of 9.6%compared to the reference scheme,and the total performance can be improved by up to 15.9%.

关键词： Task allocation intelligent connected vehicles dispersed computing matching algorithm

Role of Stokes Drift in Ocean Dynamics Under Typhoon Conditions in the Bohai Sea

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Journal of Ocean University of China 2024年第1期23卷 33-45页

作者： LI Haoqian wan Kai wanG Menghan DENG zeng’an CAO Yu North China Sea Marine Forecasting Center Qingdao 266061China Shandong Provincial Key Laboratory of Marine Ecology and Environment&Disaster Prevention and Mitigation Qingdao 266061China North China Sea Offshore Engineering Survey Institute Qingdao 266061China School of Marine Science and Technology Tianjin UniversityTianjin 300072China South China Sea Marine Forecasting Center Guangzhou 510006China

The effect of Stokes drift production(SDP),which includes Coriolis-Stokes forcing,Langmuir circulation,and Craik-Lei-bovich vortexes,on the upper ocean during typhoon passage in the Bohai Sea(BS),China,is investigated by using a coupled wave-current *** role of SDP in turbulent mixing and the further dynamics during the entire typhoon period are comprehensively *** results show that SDP greatly increases turbulent mixing at all depths under typhoon conditions by up to seven times that under normal weather *** generally strengthens sea surface cooling by more than 0.4℃,with the maximum reduction in sea surface temperature(SST)at the during-typhoon stage exceeding 2℃,which is approximately seven times larger than that under normal weather *** SDP-induced decrease in current speed can exceed 0.2ms^(-1),and the change in current direction is generally opposite the wind *** results suggest that Stokes drift depresses the effect of strong winds on currents by intensifying turbulent *** layer depth(MLD)is distinctly increased by O(1)during typhoons due to SDP and can deepen by more than *** addition,the continuous effects of SDP on SST,current,and MLD at the after-typhoon stage indi-cate a hysteretic response between SDP and typhoon actions.

关键词： Stokes drift production Langmuir turbulence rurbulent mixing typhoon coupled model

Fabrication of surface passivated two-dimensional MFI zeolite for alkylation between toluene with methanol

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Frontiers of Chemical Science and Engineering 2024年第4期18卷 115-124页

作者： Zhenyuan Zou Shengzhi Gan ting Pu Xingxing zeng Yi Huang Baoyu Liu School of Chemical Engineering and Light Industry Guangdong University of TechnologyGuangzhou 510006China School of Engineering Institute for Materials&Processesthe University of EdinburghEdinburgh EH93FBUnited Kingdom

The fabrication of suitable MFI zeolites to effectively produce para-xylene through the alkylation between toluene and methanol is highly ***,the two-dimensional pillared MFI zeolite was modified by silicalite-1,and its morphology and structure were systematically investigated by tuning the concentration of Si species during the secondary crystallization *** MFI zeolites were characterized by X-ray diffraction,transmission electron microscopy,pyridine-infrared and N_(2) adsorption-desorption *** characterization results showed that the external Brønsted acid sites of surface passivated P-MFI-x samples have been successfully ***,the P-MFI-23 showed long lifetime and high selectivity of para-xylene(about 35%)based on the cooperation between opened interlamellar structure and passivated silicalite-1 *** was found that the accumulated hard coke in the interior of MFI zeolites not only blocked the channels of zeolites but also covered the acidic sites,resulting in the deactivation of ***,the highest selectivity of para-xylene(about 48%)can be achieved for P-MFI-30 under harsh reaction condition,which also exhibited excellent regeneration property in the alkylation reaction between toluene and *** strategy described in present research may open a window for the design of other advanced materials.

关键词： alkylation MFI nanosheets catalysis

Reliability of DC-link capacitor in pulsed power supply for accelerator magnet

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Nuclear Science and Techniques 2024年第9期35卷 28-40页

作者： Jie wang Da-Qing Gao wan-zeng Shen Hong-Bin Yan Li-Jun Mao Institute of Modern Physics Chinese Academy of SciencesLanzhou 730000China School of Nuclear Science and Technology Lanzhou UniversityLanzhou 730000China School of Nuclear Science and Technology University of Chinese Academy of SciencesBeijing 100049China

Capacitors are widely used in pulsed magnet power supplies to reduce ripple voltage,store energy,and decrease power *** this study,DC-link capacitors in pulsed power supplies were *** deriving an analytical method for the capacitor current on the H-bridge topology side,the root-mean-square value of the capacitor current was calculated,which helps in selecting the DC-link *** proposed method solves this problem quickly and with high *** current reconstruction of the DC-link capacitor is proposed to avoid structural damage in the capacitor’s current measurement,and the capacitor’s hotspot temperature and temperature rise are calculated using the FFT *** test results showed that the error between the calculated and measured temperature increases was within 1.5℃.Finally,the lifetime of DC-link capacitors was predicted based on Monte Carlo *** proposed method can evaluate the reliability of DC-link capacitors in a non-isolated switching pulsed power supply for accelerators and is also applicable to film capacitors.

关键词： Aluminum electrolytic capacitor DC-link current DC–DC power converter Hotspot temperature

Improvement of epilepsy secondary to acquired immunodeficiency syndrome with intestinal microbiota preparations:a case report

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Acta Epileptologica 2024年第2期7卷 137-142页

作者： Chuhui Lin ting zeng Yuhong Deng Department of Clinical Nutrition the Second Affiliated Hospital of Guangzhou Medical UniversityGuangzhou 510260China Institute of Neuroscience and Department of Neurology the Second Affiliated Hospital of Guangzhou Medical UniversityGuangzhou 510260China

Background Epilepsy secondary to acquired immunodeficiency syndrome(AIDS)can be challenging to *** potential interactions between antiretroviral drugs and antiepileptic drugs may result in the failure of both ***,it is crucial to develop more effective strategies to enhance the clinical outcomes of *** presentation We report a case of epilepsy secondary to *** administration of Bacteroides Fragilis 839(BF839),the secondary generalized tonic-clonic seizures disappeared,the frequency of complex partial seizures decreased by 70%,and the duration of each episode was ***,long-term diarrhea associated with antiretroviral therapy for AIDS resolved,and the syphilis serofast reaction turned *** serious adverse reactions were observed during the three-year follow *** This case report suggests that the specific gut microbiota preparation could possibly improve refrac-tory epilepsy in HIV patients while also potentially alleviating adverse reactions to antiretroviral drugs and concurrent syphilis *** case may provide a new perspective for the treatment of HIV infection/AIDS.

关键词： Acquired immunodefciency syndrome Epilepsy Bacteroides fragilis

Structure Regulation of Electric Double Layer via Hydrogen Bonding Effect to Realize High-Stability Lithium-Metal Batteries

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Energy & Environmental Materials 2024年第3期7卷 72-83页

作者： Sheng Liu Chaozhu Shu Yu Yan Dayue Du Longfei Ren ting zeng Xiaojuan Wen Haoyang Xu Xinxiang wang Guilei Tian Ying zeng College of Materials and Chemistry&Chemical Engineering Chengdu University of Technology1#DongsanluErxianqiaoChengdu 610059China Institute of Fundamental and Frontier Sciences University of Electronic Science and Technology of ChinaChengdu 611731China State Key Laboratory of Polymer Materials Engineering Polymer Research InstituteSichuan UniversityChengdu 610065China

The interfacial chemistry of solid electrolyte interphases(SEI)on lithium(Li)electrode is directly determined by the structural chemistry of the electric double layer(EDL)at the ***,a strategy for regulating the structural chemistry of EDL via the introduction of intermolecular hydrogen bonds has been proposed(p-hydroxybenzoic acid(pHA)is selected as proof-of-concept).According to the molecular dynamics(MD)simulation and density functional theory(DFT)calculation results,the existence of hydrogen bonds realizes the anion structural rearrangement in the EDL,reduces the lowest unoccupied molecular orbital(LUMO)energy level of anions in the EDL,and the number of free solvent molecules,which promotes the formation of inorganic species-enriched SEI and eventually achieves the dendrite-free Li *** on this strategy,Li‖Cu cells can stably run over 185 cycles with an accumulated active Li loss of only 2.27 mAh cm^(-2),and the long-term cycle stability of Li‖Li cells is increased to 1200 *** addition,the full cell pairing with the commercial LiFePO_(4)(LFP)cathodes exhibits stable cycling performance at 1C,with a capacity retention close to 90%after 200 cycles.

关键词： electric double layer electrolyte additives intermolecular hydrogen bonds Li metal batteries p-Hydroxybenzoic acid

Evolution of interfacial heat transfer,contact behavior and microstructure during sub-rapid solidification of molten steel with different hydrogen contents

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Journal of Iron and Steel Research International 2024年第1期31卷 215-223页

作者： Cheng Lu wan-lin wang Chen-yang Zhu Jie zeng Xin-yuan Liu Hua-long Li School of Metallurgy and Environment Central South UniversityChangsha410083HunanChina National Center for International Research of Clean Metallurgy Central South UniversityChangsha410083HunanChina Institute of Research of Iron and Steel ShasteelZhangjiagang215625JiangsuChina

Typical Q235 low-carbon steel samples with different hydrogen contents(0.0004,0.0008,and 0.0013 wt.%)were prepared by adjusting the environment humidity and *** effects of hydrogen on interfacial heat transfer,contact behavior,and microstructure evolution were investigated using a novel droplet solidification *** results revealed that when the hydrogen content increases from 0.0004 to 0.0013 wt.%,the maximum heat flux between the molten steel and cooling substrate decreases from 8.01 to 6.19 MW/m^(2),and the total heat removed in the initial 2 s reduces from 10.30 to 8.27 MJ/m^(2).Moreover,the final contact angle between the molten steel and substrate increases from 103.741°to 113.697°,and the number of pores on the droplet bottom surface increases significantly from 21 to 210 with the increase in *** surface roughness of the droplet bottom surface increases from 20.902 to 49.181 *** addition,the average grain size of the droplet increases from 14.778 to 33.548 pm with the increase in the hydrogen *** interfacial contact condition becomes worse due to the escape of hydrogen from the steel matrix during the cooling process,which leads to the reduction in the interfacial heat transfer and the increase in the grain size.

关键词： Strip casting Hydrogen content Interfacial heat transfer behavior Contact behavior Microstructure evolution

Nonlinear optics of two-dimensional heterostructures

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Frontiers of physics 2024年第3期19卷 19-27页

作者： Xiangkun zeng Chenyu wan Zhichen Zhao Di Huang Zhanshan wang Xinbin Cheng Tao Jiang MOE Key Laboratory of Advanced Micro-Structured Materials Shanghai Frontiers Science Center of Digital OpticsInstitute of Precision Optical Engineeringand School of Physics Science and EngineeringTongji UniversityShanghai 200092China Shanghai Institute of Intelligent Science and Technology Tongji UniversityShanghai 200092China

Two-dimensional (2D) materials exhibit exceptionally strong nonlinear optical responses, benefiting from their reduced dimensionality, relaxed phase-matching requirements, and enhanced light-matter interaction. With additional degrees of freedom in the modulation of the physical properties by stacking 2D layers together, nonlinear optics of 2D heterostructures becomes increasingly fascinating. In this perspective, we provide a brief overview of recent advances in the field of nonlinear optics of 2D heterostructures, with a particular focus on their remarkable capabilities in characterization and modulation. Given the recent advances and the emergence of novel heterostructures, combined with innovative tuning knobs and advanced nonlinear optical techniques, we anticipate deeper insights into the underlying mechanisms and more associated applications in this rapidly evolving field.

关键词： nonlinear optics 2D heterostructures