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International Journal of Minerals,Metallurgy and Materials 2024年第7期31卷 1599-1616页

作者： Jiuhong zhang Xiejing Luo Yingyu Ding Luqi Chang Chaofang dong Key Laboratory for Corrosion and Protection(MOE) Institute for Advanced Materials and TechnologyUniversity of Science and Technology BeijingBeijing 100083China Beijing Advanced Innovation Center for Materials Genome Engineering Beijing 100083China

Attaining a decarbonized and sustainable energy system,which is the core solution to global energy issues,is accessible through the development of hydrogen ***-exchange membrane water electrolyzers(PEMWEs)are promising devices for hydrogen production,given their high efficiency,rapid responsiveness,and *** plates account for a relatively high percentage of the total cost and weight compared with other components of ***,optimization of their design may accelerate the promotion of *** paper reviews the advances in materials and flow-field design for bipolar ***,the working conditions of proton-exchange membrane fuel cells(PEMFCs)and PEMWEs are compared,including reaction direction,operating temperature,pressure,input/output,and ***,the current research status of bipolar-plate substrates and surface coatings is summarized,and some typical channel-rib flow fields and porous flow fields are ***,the effects of materials on mass and heat transfer and the possibility of reducing corrosion by improving the flow field structure are ***,this review discusses the potential directions of the development of bipolar-plate design,including material fabrication,flow-field geometry optimization using threedimensional printing,and surface-coating composition optimization based on computational materials science.

关键词： bipolar-plates flow design mass and heat transfer corrosion water electrolyzers fuel cells

Data and Model Driven Task Offloading Strategy in the Dynamic Mobile Edge Computing System

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Journal of Systems Science & Complexity 2024年第1期37卷 351-368页

作者： dong Hairong WU Wei SONG Haifeng LIU Zhen zhang Zixuan School of Electronic and Information Engineering Beijing Jiaotong UniversityBeijing 100044China School of Electronic and Information Engineering BeiHang UniversityBeijing 100191China CRSC Research&Design Institute Group Co. Ltd.Beijing 100070China

Mobile Edge Computing(MEC)provides communication and computational capabilities for the industrial Internet,meeting the demands of latency-sensitive ***,traditional model-driven task offloading strategies face challenges in adapting to situations with unknown network communication status and computational *** limitation becomes notably significant in complex industrial networks of high-speed *** by these considerations,a data and model-driven task offloading problem is proposed in this paper.A redundant communication network is designed to adapt to anomalous channel states when tasks are offloaded to edge *** link switching mechanism is executed by the train according to the attributes of the completed *** task offloading optimization problem is formulated by introducing data-driven prediction of communication states into the traditional ***,the optimal strategy is achieved by employing the informer-based prediction algorithm and the quantum particle swarm optimization method,which effectively tackle real-time optimization problems due to their low time *** simulations illustrate that the data and model-driven task offloading strategy can predict the communication state in advance,thus reducing the cost of the system and improving its robustness.

关键词： Data driven model informer mobile edge computing quantum particle swarm optimization task offloading.

Data-Driven Learning Control Algorithms for Unachievable Tracking Problems

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IEEE/CAA Journal of Automatica Sinica 2024年第1期11卷 205-218页

作者： Zeyi zhang Hao Jiang dong Shen Samer S.Saab the School of Mathematics Renmin University of ChinaBeijing 100872China IEEE the School of Engineering Lebanese American UniversityByblos 2038Lebanon

For unachievable tracking problems, where the system output cannot precisely track a given reference, achieving the best possible approximation for the reference trajectory becomes the objective. This study aims to investigate solutions using the Ptype learning control scheme. Initially, we demonstrate the necessity of gradient information for achieving the best ***, we propose an input-output-driven learning gain design to handle the imprecise gradients of a class of uncertain systems. However, it is discovered that the desired performance may not be attainable when faced with incomplete *** address this issue, an extended iterative learning control scheme is introduced. In this scheme, the tracking errors are modified through output data sampling, which incorporates lowmemory footprints and offers flexibility in learning gain *** input sequence is shown to converge towards the desired input, resulting in an output that is closest to the given reference in the least square sense. Numerical simulations are provided to validate the theoretical findings.

关键词： Data-driven algorithms incomplete information iterative learning control gradient information unachievable problems

Joint fuzzy background and adaptive foreground model for moving target detection

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Frontiers of Computer Science 2024年第2期18卷 93-106页

作者： Dawei zhang Peng WANG Yongfeng dong Linhao LI Xin LI School of Artificial Intelligence Hebei University of TechnologyTianjin 300401China Lane Department of Computer Science and Electrical Engineering West Virginia UniversityMorgantownWV 26506-6109USA

Moving target detection is one of the most basic tasks in computer *** conventional wisdom,the problem is solved by iterative optimization under either Matrix Decomposition(MD)or Matrix Factorization(MF)*** utilizes foreground information to facilitate background *** uses noise-based weights to fine-tune the *** both noise and foreground information contribute to the recovery of the *** jointly exploit their advantages,inspired by two framework complementary characteristics,we propose to simultaneously exploit the advantages of these two optimizing approaches in a unified framework called Joint Matrix Decomposition and Factorization(JMDF).To improve background extraction,a fuzzy factorization is *** fuzzy membership of the background/foreground association is calculated during the factorization process to distinguish their contributions of both to background *** describe the spatio-temporal continuity of foreground more accurately,we propose to incorporate the first order temporal difference into the group sparsity constraint *** temporal constraint is adjusted *** foreground and the background are jointly estimated through an effective alternate optimization process,and the noise can be modeled with the specific probability *** experimental results of vast real videos illustrate the effectiveness of our *** with the current state-of-the-art technology,our method can usually form the clearer background and extract the more accurate ***-noise experiments show the noise robustness of our method.

关键词： matrixdecomposition matrix factorization generalized sparsity noise modeling

Environmentally persistent free radicals in PM_(2.5)from a typical Chinese industrial city during COVID-19 lockdown:The unexpected contamination level variation

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Journal of Environmental Sciences 2024年第1期135卷 424-432页

作者： Lingyun Wang Wuduo Zhao Peiru Luo Qingyun He Wenfen zhang Chuan dong Yanhao zhang College of Chemistry Zhengzhou UniversityZhengzhou 450001China Center of Advanced Analysis and Gene Sequencing Key Laboratory of Molecular Sensing and Harmful Substances Detection TechnologyZhengzhou UniversityZhengzhou 450001China State Key Laboratory of Environmental and Biological Analysis Department of ChemistryHong Kong Baptist UniversityHong Kong 999077China Institute of Environmental Science Shanxi UniversityTaiyuan 030006China

The outbreak of COVID-19 has caused concerns *** reduce the rapid transmission of the virus,strict city lockdown measures were conducted in different *** is the country that takes the earliest home-based quarantine for *** normal industrial and social activities were suspended,the spread of virus was efficiently ***,another merit of the city lockdown measure was noticed,which is the improvement of the air *** levels of multiple atmospheric pollutants were ***,in this work,24 and 14 air fine particulate matter(PM_(2.5))samples were continuously collected before and during COVID-19 city lockdown in Linfen(a typical heavy industrial city in China),and intriguingly,the unreduced concentration was found for environmentally persistent free radicals(EPFRs)in PM_(2.5)after normal life *** primary non-stopped coal combustion source and secondary Cu-related atmospheric reaction may have impacts on this *** cigarette-based assessment model also indicated possible exposure risks of PM_(2.5)-bound EPFRs during lockdown of *** study revealed not all the contaminants in the atmosphere had an apparent concentration decrease during city lockdown,suggesting the pollutants with complicated sources and formation mechanisms,like EPFRs in PM_(2.5),still should not be ignored.

关键词： PM_(2.5) EPFRs COVID-19 City lockdown Health risks

Magnetic Co-doped 1D/2D structuredγ-Fe_(2)O_(3)/MoS_(2) effectively activated peroxymonosulfate for efficient abatement of bisphenol A via both radical and non-radical pathways

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Frontiers of Environmental Science & Engineering 2024年第3期18卷 143-159页

作者： Junge Xu dong Wang Die Hu Ziwei zhang Junhong Chen Yingmu Wang Yifeng zhang College of Civil Engineering Fuzhou UniversityFuzhou 350116China China Nuclear Power Engineering Co. Ltd.Shenzhen 518120China Department of Environmental&Resource Engineering Technical University of DenmarkLyngby DK-2800Denmark

Iron-based catalysts have been widely used to treat refractory organic pollutants in *** this paper,magnetic Co-γ-Fe_(2)O_(3)was synthesized by a facile tartaric acid-assisted hydrothermal method,and Co-γ-Fe_(2)O_(3)/MoS_(2) nanocomposite catalyst was obtained via in situ growth of MoS_(2) nanosheets on Co-γ-Fe_(2)O_(3)*** nanocomposite catalysts were used to decompose bisphenol A(BPA)by activating peroxymonosulfate(PMS).It was shown that only 0.15 g/L catalyst and 0.5 mmol/L PMS degraded 10 mg/L of BPA(99.3%within 10 min)in the pH range of 3–*** was activated due to redox cycling among the pairs Co(III)/Co(II),Fe(III)/Fe(II),and Mo(VI)/Mo(IV).Quenching experiments and electron paramagnetic resonance spectroscopy demonstrated that both radical and non-radical pathways were involved in BPA degradation,in which active radical sulfate radical and non-radical singlet oxygen were the main reactive oxygen *** intermediates were identified by liquid chromatography-coupled mass spectrometry,and three possible BPA degradation pathways were *** toxicity of several degradation intermediates was lower,and Co-γ-Fe_(2)O_(3)/MoS_(2) exhibited excellent reusability and could be magnetically recovered.

关键词： Magnetic Co-γ-Fe_(2)O_(3) /MoS_(2) Hydrothermal method Bisphenol A Degradation pathways Toxicity analysis

Towards full-stack deep learning-empowered data processing pipeline for synchrotron tomography experiments

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The Innovation 2024年第1期5卷 127-138页

作者： Zhen zhang Chun Li Wenhui Wang Zheng dong Gongfa Liu Yuhui dong Yi zhang National Synchrotron Radiation Laboratory University of Science and Technology of ChinaHefei 230029China Beijing Synchrotron Radiation Facility Institute of High Energy PhysicsChinese Academy of SciencesBeijing 100049China

Synchrotron tomography experiments are transitioning into multifunctional,cross-scale,and dynamic characterizations,enabled by new-generation synchrotron light sources and fast developments in beamline ***,with the spatial and temporal resolving power entering a new era,this transition generates vast amounts of data,which imposes a significant burden on the data processing ***,as a highly accurate and efficient data processing method,deep learning shows great potential to address the big data challenge being encountered at future synchrotron *** this review,we discuss recent advances employing deep learning at different stages of the synchrotron tomography data processing *** also highlight how applications in other data-intensive fields,such as medical imaging and electron tomography,can be migrated to synchrotron ***,we provide our thoughts on possible challenges and opportunities as well as the outlook,envisioning selected deep learning methods,curated big models,and customized learning strategies,all through an intelligent scheduling solution.

关键词： processing pipeline outlook

Multiscale engineering of molecular electrocatalysts for the rapid hydrogen evolution reaction

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Nano Research 2024年第7期17卷 6026-6031页

作者： Huan Li zhan Jiang Yubo Yuan Yirong Tang Jie Zao Wentao zhang Peiyi Han Xun zhang Bulin Chen Yongye Liang Department of Materials Science and Engineering Southern University of Science and TechnologyShenzhen 518055China South China Institute of Environmental Sciences Guangzhou 510655China

Molecular electrocatalysts have demonstrated potential for the hydrogen evolution reaction(HER)due to their well-defined structures and high intrinsic *** rapid production of hydrogen requires molecular electrocatalysts to operate at high current densities,which still presents a *** this work,we demonstrate that molecularly dispersed electrocatalysts of cobalt phthalocyanine anchored on carbon nanotubes(CoPc MDEs)are superior candidates due to the efficient charge transport between the substrate and the active *** intrinsic activity can be enhanced by introducing functional groups on *** facilitate mass transport,di(ethylene glycol)substituted CoPc molecules are further anchored on a threedimensional self-supported electrode(CoPc-DEG MDE@CC),enabling continuous operation for 25 h at−1000 mA/cm^(2)in 1.0 M *** study demonstrates the potential of molecular electrocatalysts for HER and emphasizes the importance of adjusting intrinsic activity,and charge and mass transport capacity for practical molecular electrocatalysts.

关键词： hydrogen evolution reaction cobalt phthalocyanine intrinsic activity mass transport

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中部六省产业结构调整研究

经济经纬 2005年第6期22卷 109-112页

作者：张占东河南财经学院国际经济与贸易系河南郑州450011

中部塌陷的形成既有国家产业布局政策的原因，也有中部六省自身产业结构缺陷的原因，它会给我国经济发展造成整体性的危害。实现中部崛起是我国区域经济协调发展的内在要求，是建设和谐社会的迫切需要，它对保持和提升我国国际竞争力具... 详细信息

中部塌陷的形成既有国家产业布局政策的原因，也有中部六省自身产业结构缺陷的原因，它会给我国经济发展造成整体性的危害。实现中部崛起是我国区域经济协调发展的内在要求，是建设和谐社会的迫切需要，它对保持和提升我国国际竞争力具有重大意义。实现中部崛起，除争取国家政策支持外，应基于比较优势和竞争优势，大力发展优势产业；选择主导产业，促进支柱产业发展；以高新技术和先进适用技术改造提升传统产业，有选择地培育发展高新技术产业；着力调整农业结构、工业结构，支持新型服务业的发展。

关键词：中部塌陷中部崛起和谐社会产业结构

Improving fatigue properties of normal direction ultrasonic vibration assisted face grinding Inconel 718 by regulating machined surface integrity

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International Journal of Extreme Manufacturing 2024年第3期6卷 458-475页

作者： Nianwei Xu Renke Kang Bi zhang Yuan zhang Chenxu Wang Yan Bao Zhigang dong State Key Laboratory of High-Performance Precision Manufacturing Dalian University of TechnologyDalian 116024People’s Republic of China Department of Mechanical and Energy Engineering Southern University of Science and TechnologyShenzhen 518055People’s Republic of China

Fatigue properties are crucial for critical aero-engine components in extreme serviceenvironments,which are significantly affected by surface integrity(SI)indexes(especially surface topography,residual stressσ_(res),and microhardness)after machining ***-direction ultrasonic vibration-assisted face grinding(ND-UVAFG)has advantages in improving the machinability of Inconel 718,but there is a competitive relationship between higher compressiveσ_(res)and higher surface roughness R_(a)in affecting fatigue *** lack of a quantitative relationship between multiple SI indexes and fatigue strength makes theindeterminacy of a regulatory strategy for improving fatigue *** this work,a model of fatigue strength(σ_f)_(sur)considering multiple SI indexes was ***,high-cycle fatigue tests were carried out on Inconel 718 samples with different SI characteristics,and the influence of ND-UVAFG process parameters on SI was *** on SI indexes data,the(σ_f)_(sur)distribution in the grinding surface layer for ND-UVAFG Inconel 718 samples was determined using the developed model,and then the fatigue crack initiation(FCI)sites were *** predicted FCI sites corresponded well with the experimental results,therebyverifying this model.A strategy for improving the fatigue life was proposed in this work,which was to transfer the fatigue source from the machined surface to the bulk material by controlling the SI ***,a critical condition of SI indexes that FCI sites appeared on the surface or in bulk material was given by fitting the predicted *** to the critical condition,an SI field where FCI sites appeared in the bulk material could be *** this field,thefatigue life of Inconel 718 samples could be improved by approximately 140%.

关键词： surface integrity fatigue strength Inconel 718 ultrasonic assisted grinding