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An open dataset of data lineage graphs for data governance research

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Visual Informatics 2024年第1期8卷 1-5页

作者： Yunpeng Chen Ying Zhao Xuanjing Li jiang Zhang jiang long Fangfang Zhou Central South University ChangshaHunanChina Huawei Cloud Computing Technology Co. Ltd.HangzhouZhejiangChina

Data have become valuable assets for *** governance aims to manage and reuse data assets,facilitating enterprise management and enabling product innovations.A data lineage graph(DLG)is an abstracted collection of data assets and their data lineages in data *** DLGs can provide rich data insights for data ***,the progress of data governance technologies is hindered by the shortage of available open datasets for *** paper introduces an open dataset of DLGs,including the DLG model,the dataset construction process,and applied *** real-world dataset is sourced from Huawei Cloud Computing Technology Company Limited,which contains 18 DLGs with three types of data assets and two types of *** the best of our knowledge,this dataset is the first open dataset of DLGs for data *** dataset can also support the development of other application areas,such as graph analytics and visualization.

关键词： Data asset Data governance Data lineage Graph Open dataset

The Mass Assembly History for Galaxies with MaNGA

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Research in Astronomy and Astrophysics 2024年第3期24卷 58-69页

作者： Xue Ge Hong-Tao Wang Cheng-long Lei Yun-Jun Guo Yi-long jiang Xiao-Xiao Cao School of Physics and Information Engineering Jiangsu Second Normal University jiangsu Province Engineering Research Center of Basic Education Big Data Application Jiangsu Second Normal University Key Laboratory of Modern Astronomy and Astrophysics Nanjing UniversityMinistry of Education School of Science Langfang Normal University

How galaxies assemble masses through their own star formation or interaction with the external environment is still an important topic in the field of galaxy formation and *** use Value Added Catalogs with galaxy features that are spatially and temporally resolved from Sloan Digital Sky Survey Data Release 17 to investigate the mass growth histories of early-type galaxies(ETGs)and late-type galaxies(LTGs).We find that the mass growth of ETGs is earlier than that of LTGs for massive galaxies(M_(*)>10^(10)M_⊙),while low-mass(M_(*)≤10^(10)M_⊙)ETGs have statistically similar mass assembly histories as low-mass *** stellar metallicity of all massive galaxies shows a negative gradient and basically does not change with ***,in low-mass galaxies,the stellar metallicity gradient of elliptical galaxies is negative,and the stellar metallicity gradient of lenticular and spiral galaxies evolves from positive to *** are not all in a high-density environment,but exhibit mass *** the tidal strength increases,the star formation rate of low-mass ETGs rapidly *** results support a picture where massive galaxies exhibit inside-out quenching mode,while low-mass galaxies show outside-in quenching *** effects play an important role in regulating the mass assembly histories of low-mass ETGs.

关键词： Galaxy evolution-galaxies star formation-Galaxy formation

Boost the Utilization of Dense FeN_(4) Sites for High-Performance Proton Exchange Membrane Fuel Cells

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Energy & Environmental Materials 2024年第3期7卷 398-405页

作者： Yanrong Li Shuhu Yin long Chen Xiaoyang Cheng Chongtai Wang Yanxia jiang Shigang Sun State Key Laboratory of Physical Chemistry of Solid Surfaces Engineering Research Center of Electrochemical Technologies of Ministry of EducationCollege of Chemistry and Chemical Engineering and Discipline of Intelligent Instrument and EquipmentXiamen UniversityXiamen 361005China College of Chemistry and Chemical Engineering Key Laboratory of Electrochemical Energy Storage and Energy Conversion of Hainan ProvinceHainan Normal UniversityHaikou 571158China

Iron-nitrogen-carbon(Fe-N-C)catalysts for the oxygen reduction reaction(ORR)in proton exchange membrane fuel cells(PEMFCs)have seriously been hindered by their poor ORR performance of Fe-N-C due to the low active site density(SD)and site ***,we reported a melamine-assisted vapor deposition approach to overcome these *** melamine not only compensates for the loss of nitrogen caused by high-temperature pyrolysis but also effectively etches the carbon substrate,increasing the external surface area and mesoporous porosity of the carbon *** can provide more useful area for subsequent vapor deposition on active *** prepared 0.20Mela-FeNC catalyst shows a fourfold higher SD value and site utilization than the FeNC without the treatment of *** a result,0.20Mela-FeNC catalyst exhibits a high ORR activity with a half-wave potential(E_(1/2))of 0.861 V and 12-fold higher ORR mass activity than the FeNC in acidic *** the cathode in a H_(2)-O_(2)PEMFCs,0.20Mela-FeNC catalyst demonstrates a high peak power density of 1.30 W cm^(-2),outstripping most of the reported Fe-N-C *** developed melamine-assisted vapor deposition approach for boosting the SD and utilization of Fe-N-C catalysts offers a new insight into high-performance ORR electrocatalysts.

关键词： fuel cells melamine oxygen reduction reaction site density utilization

Experimental study on mix proportion optimization of anti-calcium dissolution shotcrete for tunnels based on response surface methodology

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Underground Space 2024年第2期15卷 203-220页

作者： Chongming Tian Yueping Tong Junyuan Zhang fei Ye Guifeng Song Yin jiang Meng Zhao School of Highway Chang’an UniversityXi’an 710064China Yunnan Laman Expressway Co. Ltd.Yunnan Xishuangbanna 666300China Hebei Traffic Planning Design Institute Shijiazhuang 050035China

Aiming at the issue of crystallization and blockage of drainage system due to the massive calcium loss from the tunnel shotcrete,a selfdesigned tunnel seepage crystallization modelling system was *** system was produced in conjunction with the initial tunnel support shotcrete construction and drainage pipe installation,and is capable of simulating both the seepage process of groundwater in the shotcrete and the process of crystallization in the drainage *** on three different mechanisms of anti-crystallization,which include absorbing free calcium,reducing the porosity and increasing hydrophobicity,antialkali agent,nano-calcium carbonate,and silane were selected to test,***,the suitable dosing ranges of these three external admixtures for resisting calcium loss in shotcrete were determined by single factor tests,which were 7%–11%,4%–8%,and 0.3%–0.5%,***,the response surface method was employed to evaluate the interaction of antialkali agent,nano-calcium carbonate and silane on calcium loss in shotcrete,and to establish the relationship between them,and thus to determine the admixture ratio that can effectively reduce calcium loss crystallization in shotcrete,with the optimal admixture amounts of antialkali agent being 9.242%,nano-calcium carbonate 4.889%and silane 0.366%.Lastly,the reliability of the model test results was verified by the microscopic analysis,and the results showed that the total amount of calcium dissolution in the optimized group could be reduced by 75%compared with the blank control group,and was basically consistent with that derived from the response surface regression model,validating the high accuracy of the buildup response surface regression *** present study can provide some ideas and references for reducing the seepage crystallization behavior of groundwater in the initial tunnel support shotcrete.

关键词： Tunnel engineering Calcium loss Crystallization blockage Model test Response surface methodology Interaction effect

Experimental and simulation research on hollow AZ31 magnesium alloy three-channel joint by hot extrusion forming with sand mandrel

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Journal of Magnesium and Alloys 2024年第1期12卷 98-109页

作者： Shi Shengnan Wang Hongyu Teng fei jiang Lei Sun Juncai Sun Jie Zhang Shunhu Transportation Engineering College Dalian Maritime UniversityDalianLiaoning 106026China State Key Laboratory of Rolling and Automation Northeastern UniversityShenyangLiaoning 110819China Shagang School of Iron and Steel Soochow UniversitySuzhouJiangsu 215021China

Magnesium alloy is one of the lightest metal structural *** weight is further reduced through the hollow ***,the hollow structure is easily damaged during *** order to maintain the hollow structure and to transfer the stresses during the high temperature deformation,the sand mandrel is *** this paper,the hollow AZ31 magnesium alloy three-channel joint is studied by hot extrusion *** as one of solid granule medium is used to fill the hollow magnesium *** extrusion temperatures are 230℃ and 300℃,*** process parameters(die angle,temperature,bottom thickness,sidewall thickness,edge-to-middle ratio in bottom,bottom shape)of the hollow magnesium alloy are analyzed based on the results of experiments and the finite element *** results are shown that the formability of the hollow magnesium alloy will be much better when the ratio of sidewall thickness to the bottom thickness is 1:*** when edge-to-middle ratio in bottom is about 1:1.5,a better forming product can be *** best bottom shape in these experiments will be convex based on the forming *** grain will be refined obviously after the *** the microstructures will be shown as *** these lines will be well agreement with the mold in the corner.

关键词： AZ31 magnesium alloy Three-channel joint Sand Experiments and the finite element Die angle

Component modeling and updating method of integrated energy systems based on knowledge distillation

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Energy and AI 2024年第2期16卷 184-199页

作者： Xueru Lin Wei Zhong Xiaojie Lin Yi Zhou long jiang Liuliu Du-Ikonen long Huang Shanghai Institute for Advanced Study Zhejiang UniversityShanghaiChina College of Energy Engineering Zhejiang UniversityHangzhouChina Jiaxing Research Institute Zhejiang UniversityJiaxingChina Department of Sustainability Science LUT UniversityLappeenrantaFinland School of Intelligent Manufacturing Ecosystem Xi'an Jiaotong-Liverpool UniversitySuzhouChina

Amid the backdrop of carbon neutrality, traditional energy production is transitioning towards integrated energy systems (IES), where model-based scheduling is key in scenarios with multiple uncertainties on both supply and demand sides. The development of artificial intelligence algorithms, has resolved issues related to model accuracy. However, under conditions of high proportion renewable energy integration, component load adjustments require increased flexibility, so the mathematical model of the component must adapt to constantly changing operating conditions. Therefore, the identification of operating condition changes and rapid model updating are pressing issues. This study proposes a modeling and updating method for IES components based on knowledge distillation. The core of this modeling method is the light weighting of the model, which is achieved through a knowledge distillation method, using a teacher-student mode to compress complex neural network models. The triggering of model updates is achieved through principal component analysis. The study also analyzes the impact of model errors caused by delayed model updates on the overall scheduling of IES. Case studies are conducted on critical components in IES, including coal-fired boilers and turbines. The results show that the time consumption for model updating is reduced by 76.67 % using the proposed method. Under changing conditions, compared with two traditional models, the average deviation of this method is reduced by 12.61 % and 3.49 %, respectively, thereby improving the model's adaptability. The necessity of updating the component model is further analyzed, as a 1.00 % mean squared error in the component model may lead to a power deviation of 0.075 MW. This method provides real-time, adaptable support for IES data modeling and updates.

关键词： Component modeling Adaptive update Knowledge distillation Variable operating conditions Integrated energy system Data-driven

Promoted hydrogenation of CO2 to methanol over single-atom Cu sites with Na+-decorated microenvironment

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National Science Review 2024年第06期11卷 264-272页

作者： Li-Li Ling Xinyu Guan Xiaoshuo Liu Xiao-Mei Lei Zhongyuan Lin Hai-long jiang Hefei National Research Center for Physical Sciences at the Microscale Department of Chemistry University of Science and Technology of China School of Energy and Power Engineering North China Electric Power University School of Energy and Environment Southeast University

Although single-atom Cu sites exhibit high efficiency in CO2hydrogenation to methanol,they are prone to forming Cu nanoparticles due to reduction and aggregation under reaction conditions,especially at high ***,single-atom Cu sites stabilized by adjacent Na+ions have been successfully constructed within a metal-organic framework（MOF）-based catalyst,namely *** is found that the electrostatic interaction between the Na+and Hδ-species plays a pivotal role in upholding the atomic dispersion of Cu in MOF-808-NaCu during CO2hydrogenation,even at temperatures of up to 275℃.This exceptional stabilization effect endows the catalyst with excellent activity(306 g·kgcat-1·h-1),high selectivity to methanol（93%） and long-term stability at elevated reaction temperatures,far surpassing the counterpart in the absence of Na+（denoted as MOF-808-Cu）.This work develops an effective strategy for the fabrication of stable single-atom sites for advanced catalysis by creating an alkali-decorated microenvironment in close proximity.

关键词： single-atom sites metal–organic framework CO2 hydrogenation heterogeneous catalysis alkali-metal decoration

Molecular mechanism of a coastal cyanobacterium Synechococcus *** 7002 adapting to changing phosphate concentrations

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Marine Life Science & Technology 2024年第3期6卷 562-575页

作者： Qiao-Wei Sun Yu Gao Jordan Wang fei-xue Fu Cheng-Wen Yong Shuang-Qing Li Hai-long Huang Wei-Zhong Chen Xin-Wei Wang Hai-Bo jiang School of Marine Sciences Ningbo UniversityNingbo 315211China Southern Marine Science and Engineering Guangdong Laboratory(Zhuhai) Zhuhai 519080China School of Life Sciences Central China Normal UniversityWuhan 430079China Department of Biological Sciences University of Southern CaliforniaLos AngelesCA 90089USA

Phosphorus concentration on the surface of seawater varies greatly with different environments,especially in *** molecular mechanism by which cyanobacteria adapt to fluctuating phosphorus bioavailability is still *** this study,transcriptomes and gene knockouts were used to investigate the adaptive molecular mechanism of a model coastal cyanobacterium Synechococcus *** 7002 during periods of phosphorus starvation and phosphorus recovery(adding sufficient phosphorus after phosphorus starvation).The findings indicated that phosphorus deficiency affected the photosynthesis,ribosome synthesis,and bacterial motility pathways,which recommenced after phosphorus was *** more,most of the metabolic pathways of cyanobacteria were enhanced after phosphorus recovery compared to the control which was kept in continuous phosphorus replete *** on transcriptome,54 genes potentially related to phosphorusdeficiency adaptation were selected and knocked out individually or in *** was found that five mutants showed weak growth phenotype under phosphorus deficiency,indicating the importance of the genes(A0076,A0549-50,A1094,A1320,A1895)in the adaptation of phosphorus *** mutants were found to grow better than the wild type under phosphorus deficiency,suggesting that the products of these genes(A0079,A0340,A2284–86)might influence the adaptation to phosphorus *** analysis revealed that cyanobacteria exposed to highly fluctuating phosphorus concentrations have more sophisticated phosphorus acquisition *** results elucidated that Synechococcus *** 7002 have variable phosphorus response mechanisms to adapt to fluctuating phosphorus concentration,providing a novel perspective of how cyanobacteria may respond to the complex and dynamic environments.

关键词： Synechococcus sp PCC 7002 Phosphorus fluctuation Cyanobacteria ・Gene knockout Molecular mechanism

Characteristics of office lighting energy consumption and its impact on air conditioning energy consumption

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Energy and Built Environment 2024年第4期5卷 529-543页

作者： Siao Song Jibo long Hanyu jiang Bin Ran Lun Yao College of Civil Engineering Xiangtan UniversityXiangtanHunan 411105China

The energy consumption of office buildings has increased sharply since the 21st century with the increasing ur-banization *** this stage,the energy consumption of office buildings in China mainly comes from air conditioning and *** paper obtains the regression equation of natural lighting illumination and radi-ant heat gain under different curtain conditions through experiments and simulations,and gives the theoretical calculation process of curtain regulation of office thermal and light environment and energy *** and Ecotect software were used to analyze the thermal and light environment and energy consumption of the *** results show that setting curtains in the room can effectively improve the indoor thermal light en-vironment,the higher the transmittance of curtains the lower the lighting energy consumption,the higher the number of high temperature hours of natural room temperature and the greater the radiant heat *** room with thick curtains has the lowest energy consumption for air conditioning in summer,followed by the room with thin curtains,and the room without curtains has the highest energy consumption for air *** room without curtains has the lowest energy consumption for artificial lighting,the room with thin curtains has the second lowest,and the room with thick curtains has the highest electricity consumption for artificial *** air conditioning energy consumption accounts for the main building energy consumption,followed by the lighting energy *** setting curtains in the office,the air conditioning energy consumption caused by the solar radiation heat entering the room through the exterior windows is smaller than the lighting energy consumption caused by artificial ***,the installation of internal shading with moderate trans-mittance and good thermal insulation performance can make the energy saving of lighting and air conditioning energy consumption reach the

关键词： Curtains Light environment Thermal environment Energy saving