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Real-time prediction of tunnel face conditions using XGBoost Random Forest algorithm

Frontiers of Structural and Civil Engineering 2023年第12期17卷 1777-1795页

作者： lei-jie WU Xu LI Ji-dong yuan Shuang-jing WANG Key Laboratory of Urban Underground Engineering of Ministry of Education Beijing Jiaotong UniversityBeijing 100044China School of Computer and Information Technology Beijing Jiaotong UniversityBeijing 100044China

Real-time perception of rock conditions based on continuously collected data to meet the requirements of continuous Tunnel Boring Machine(TBM)construction presents a critical challenge that warrants increased *** achieve this goal,this paper establishes real-time prediction models for fractured and weak rock mass by comparing 6 different algorithms using real-time data collected by the *** models are optimized in terms of selecting metric,selecting input features,and processing imbalanced *** results demonstrate the following points.(1)The Youden's index and area under the ROC curve(AUC)are the most appropriate performance metrics,and the XGBoost Random Forest(XGBRF)algorithm exhibits superior prediction and generalization performance.(2)The duration of the TBM loading phase is short,usually within a few minutes after the disc cutter contacts the tunnel face.A model based on the features during the loading phase has a miss rate of 21.8%,indicating that it can meet the early warning needs of TBM construction *** the TBM continues to operate,the inclusion of features calculated from subsequent data collection can continuously correct the results of the real-time prediction model,ultimately reducing the miss rate to 16.1%.(3)Resampling the imbalanced data set can effectively improve the prediction by the model,while the XGBRF algorithm has certain advantages in dealing with the imbalanced data *** the model gives an alarm,the TBM operator and on-site engineer can be reminded and take some necessary measures for avoiding potential tunnel *** real-time predication model can be a useful tool to increase the safety of TBM excavation.

关键词： Tunnel Boring Machine fractured and weak rock mass machine learning model real-time early warming tunnel facerockcondition

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Cage-confinement synthesis of MoC nanoclusers as efficient sulfiphilic and lithiophilic regulator for superior Li–S batteries

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Rare Metals 2024年第2期43卷 624-634页

作者： Xing-yuan Zhang Mei-Na lei Shan Tian Jian-Gan Wang State Key Laboratory of Solidification Processing Center for Nano Energy MaterialsSchool of Materials Science and EngineeringNorthwestern Polytechnical University and Shaanxi Joint Laboratory of Graphene(NPU)Xi’an710072China

High-energy-density Li-S batteries are subjected to serious sulfur deactivation and short cycle lifetime caused by undesirable polysulfide shuttle effect and frantic lithium dendrite *** this work,a controllable cage-confinement strategy to fabricate molybdenum carbide(MoC)nanoclusters as a high-efficient sulfiphilic and lithiophilic regulator to mitigate the formidable issues of Li-S batteries is *** sub-2 nm MoC nanoclusters not only guarantee robust chemisorption and fast electrocatalytic conversion of polysulfides to enhance the sulfur electrochemistry,but also homogenize Li^(+) flux to suppress the lithium dendrite *** a consequence,the MoC-modified separator endows the batteries with boosted reaction kinetics,promoted sulfur utilization,and improved cycling stability.A reversible capacity of 701 mAh·g^(−1) at a high rate of 5.0C and a small decay rate of 0.076%per cycle at 1.0C over 600 cycles are *** study offers a rational route for design and synthesis of bifunctional nanoclusers with both sulfiphilicity and lithiophilicity for high-performance Li-S batteries.

关键词： Li-S batteries Nanocluster Electrocatalyst Polysulfide shuttle Li dendrites

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Rule based vs Optimization based Workload Control with and without Exogenous Lead Times:An Assessment by Simulation

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Journal of Systems Science and Systems Engineering 2023年第5期32卷 553-570页

作者： Mingze yuan Ting Qu Matthias Thürer Lin Ma lei Liu School of Management Jinan UniversityGuangzhou510632China GBA and B&R International Joint Research Center for Smart Logistics Jinan UniversityZhuhai519070China School of Intelligent Systems Science and Engineering Jinan UniversityZhuhai519070China Institute of Physical Internet Jinan UniversityZhuhai519070China Factory Planning and Intralogistics Chemnitz University of TechnologyChemnitz09125Germany Department of Industrial and Systems Engineering The Hong Kong Polytechnic UniversityHong Kong999077China

Order release is a key production planning and control function,specifically in high variety contexts.A large literature on release methods that balance the workload consequently *** Workload Control methods can be rule based,using a simple greedy heuristic,optimization based or optimization based with lead times that are *** all three types of methods have the same objective,their performance has never been *** simulation,this study shows that a better on time delivery performance of jobs can be achieved by the two optimization based release *** importantly,optimization based methods that assume lead times to be exogenous significantly outperform alternative methods in terms of tardiness *** based and optimization based Workload Control without exogenous lead times overemphasize average lateness reduction,which leads to sequence deviations that offset performance improvements through *** contrast,Workload Control methods that assume lead times to be exogenous limit sequence deviations,which leads to a significant reduction in dispersion of *** has important implication for the future design of order release methods,and managerial practice.

关键词： Workload control order release production planning production control make-to-order production

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Corrosion Resistance of Friction Stir Welded Al–Cu–Li Alloy AA2099-T8

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Acta Metallurgica Sinica(English Letters) 2020年第1期33卷 127-134页

作者： Yan-Long Ma Hui-Bin Xu Zhao-yuan Liang lei Liu College of Materials Science and Engineering Chongqing University of TechnologyChongqing 400054China Chongqing Municipal Engineering Research Center of Institutions of Higher Education for Special Welding Materials and Technology Chongqing University of TechnologyChongqing 400054China

In order to study the eff ect of friction stir welding(FSW)on corrosion resistance of Al–Cu–Li alloy AA2099-T8,the microstructure and microhardness of FSW joints were characterized,and then,the corrosion behavior of the FSW joints was investigated by the immersion and potentiodynamic polarization tests in a 3.5%NaCl solution at room *** is indicated that the alloy was softened by FSW,with the lowest hardness appearing at the boundary between the nugget zone and the thermo-mechanically aff ected *** exposed to the NaCl solution,the FSW joint was characterized by shallow pits and was free of severe localized corrosion,probably due to dissolution of T 1(A 2 CuLi)phase in the FSW *** is suggested that further work should be carried out to evaluate the galvanic coupling eff ect between the FSW joint and the base metal,as well as the stress corrosion cracking resistance of the FSW joint.

关键词： Frictions stir welding(FSW) Al–Cu–Li alloy AA2099 Localized corrosion

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Effect of Mg addition on TiN inclusions in GCr15 bearing steel

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Journal of Iron and Steel Research International 2022年第6期29卷 925-938页

作者： lei Cao Guo-cheng Wang yuan-you Xiao Rong-guang Yang School of Materials and Metallurgy University of Science and Technology LiaoningAnshan 114051LiaoningChina Key Laboratory of Metallurgy Engineering Liaoning Province University of Science and Technology LiaoningAnshan 114051LiaoningChina Steel Rolling Department Shougang Jingtang United Iron and Steel Co.Ltd.Tangshan 063200HebeiChina

Compared with the original GCr15 bearing steel,TiN inclusions are greatly reduced by the effect of Mg addition,and many different types of non-metallic Mg-containing inclusions were observed in Mg-treated GCr15 bearing steel which includes MgO,MgS·MnS,MgO–MgS·MnS,MgAl_(2)O_(4)–MgS·MnS,MgO–TiN,MgS·MnS–TiN,and MgO–MgS·MnS–*** inclusion size distribution based on automatic inclusion analysis software shows that the number of inclusion with the size ranging from 1 to 3μm increases obviously because a large amount of MgO,MgS·MnS,TiN inclusions containing Mg with smaller sizes are massively *** situ observation on the experimental steel by high-temperature confocal laser scanning microscopy confirms that MgO can provide nucleation sites for *** addition,the MgS·MnS and MgO–MgS·MnS inclusions can also provide positions for the nucleation of *** calculations indicate that after Mg addition to liquid steel,a large number of fine MgO inclusions are generated in the liquid steel because of the strong reactivity of Mg and *** the same time,MgS precedes TiN precipitates in the solid–liquid two-phase region;thus,MgO and MgS·MnS can provide sites for TiN *** last,two possible formation pathways for the above various TiN inclusions containing Mg are discussed.

关键词： Mg treatment GCr15 bearing steel TiN inclusion Size distribution In situ observation

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Insights into carbon-based materials for catalytic dehydrogenation of low-carbon alkanes and ethylbenzene

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Frontiers of Chemical Science and Engineering 2023年第11期17卷 1623-1648页

作者： Sijia Xing Sixiang Zhai lei Chen Huabin Yang Zhong-Yong yuan School of Materials Science and Engineering Smart Sensing Interdisciplinary Science CenterNankai UniversityTianjin 300350China Key Laboratory of Advanced Energy Materials Chemistry(Ministry of Education) Nankai UniversityTianjin 300071China

Direct dehydrogenation with high selectivity and oxidative dehydrogenation with low thermal limit has been regarded as promising methods to solve the increasing demands of light olefins and *** catalysts have shown remarkable performance for these reactions,such as Pt,CrOx,Co,ZrOx,Zn and *** with metal-based catalysts,carbon materials with stable structure,rich pore texture and large surface area,are ideal platforms as the catalysts and the supports for dehydrogenation *** this review,carbon materials applied in direct dehydrogenation and oxidative dehydrogenation reactions including ordered mesoporous carbon,carbon nanodiamond,carbon nanotubes,graphene and activated carbon,are summarized.A general introduction to the dehydrogenation mechanism and active sites of carbon catalysts is briefly presented to provide a deep understanding of the carbon-based materials used in dehydrogenation *** unique structure of each carbon material is presented,and the diversified synthesis methods of carbon catalysts are *** approaches for promoting the catalytic activity of carbon catalysts are elaborated with respect to preparation method optimization,suitable structure design and heteroatom *** regeneration mechanism of carbon-based catalysts is discussed for providing guidance on catalytic performance *** addition,carbon materials as the support of metal-based catalysts contribute to exploiting the excellent catalytic performance of catalysts due to superior structural *** the end,the challenges in current research and strategies for future improvements are proposed.

关键词： carbon materials dehydrogenation active sites mechanism catalytic performance support

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Research Progress on the Integrated Detection Technology for Forensic Deoxyribonucleic Acid Genetic Markers and Ribonucleic Acid Molecular Markers

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Journal of Forensic Science and Medicine 2023年第1期9卷 64-69页

作者： lei Miao Jia-Hui yuan Ke-Lai kang Jie Zhao Chi Zhang Le Wang Key Laboratory of Forensic Genetics of Ministry of Public Security Institute of Forensic ScienceMinistry of Public SecurityBeijingChina Department of Forensic Medicine School of Forensic MedicineKunming Medical UniversityKunmingYunnanChina

Deoxyribonucleic acid(DNA)genetic markers and ribonucleic acid(RNA)molecular markers have been widely used in forensic practices including individual identification,parentage testing,body fluid identification,determination of the age of stains,and molecular pathological *** information of biological evidence and their interrelation could be revealed by the integrated detection of DNA/RNA *** integrated detection workflow aims to simplify working procedures,reduce time consuming and save valuable samples collected from crime ***-generation sequencing(NGS)may be an effective method for integrated DNA/RNA *** this review,DNA/RNA co-extraction strategies,simultaneous detection methods based on capillary electrophoresis were *** on NGS-based integrated detection methods of DNA and RNA markers was reviewed to provide a reference for forensic medicine researches and applications.

关键词： Forensic genetics deoxyribonucleic acid ribonucleic acid integrated detection methods next-generation sequencing

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The effect of healthy dietary patterns on male semen quality:a systematic review and meta-analysis

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Asian Journal of Andrology 2022年第5期24卷 549-557页

作者： lei-lei Cao Jun-Jie Chang Shao-Jie Wang Yong-Han Li Meng-yuan yuan Geng-Fu Wang Pu-Yu Su Department of Maternal Child and Adolescent HealthSchool of Public HealthAnhui Medical UniversityHefei 230032China Key Laboratory of Population Health Across Life Cycle(Anhui Medical University) Ministry of Education of the People’s Republic of ChinaHefei 230032China

The incidence of infertility has recently *** quality is an important male fertility indicator,and dietary factors can affect semen *** conducted this systematic review and meta-analysis to determine the effects of healthy dietary patterns on semen quality.A literature search was conducted in 3 databases(Embase,Web of Science and PubMed)on August 21,*** included cross-sectional studies examined the influence of the Mediterranean,Dietary Approaches to Stop Hypertension(DASH),and prudent diet patterns on semen quality parameters;six studies(1244 subjects)were *** comparing high consumption with low consumption of healthy dietary patterns,the results of the meta-analysis showed significantly higher sperm concentrations(mean difference[MD]=6.88×10^(6) ml^(−1),95%confidence interval[CI]:1.26×10^(6) ml^(−1)–12.49×10^(6) ml^(−1);P<0.05),a significant increase in total sperm count(MD=16.70×10^(6),95%CI:2.37×10^(6)–31.03×10^(6);P<0.05),and a significant increase in progressive sperm motility(MD=5.85%,95%CI:2.59%–9.12%;P<0.01).The sperm concentration,progressive sperm motility,and total sperm count were significantly higher in men with higher versus lower consumption of healthy dietary ***,the results must be interpreted with caution.

关键词： cross-sectional study healthy dietary pattern meta-analysis semen quality systematic review

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Impact of dataset on the study of crop disease image recognition

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International Journal of Agricultural and Biological Engineering 2022年第5期15卷 181-186页

作者： yuan yuan lei Chen Yuchen Ren Shimei Wang Yin Li Institute of Intelligent Machines Hefei Institutes of Physical ScienceChinese Academy of SciencesHefei 230031China Rice Research Institute Anhui Academy of Agricultural SciencesHefei 230001China Guangzhou Institute of Software Application Technology Guangzhou 511458China

Datasets are very important in image recognition research based on machine learning *** particular,advanced methods such as deep learning and transfer learning are more dependent on datasets used for training *** quality of datasets directly affects the final effect of these *** the research of crop disease image recognition,due to the complication of the agricultural environment and the variety of crops,datasets are scarce at ***,more and more researches adopt methods based on transfer learning,which can make up for the lack of data in the target domain with the help of other *** these methods,the selection of auxiliary domain datasets has great impact on the modeling effect of target *** order to clarify the impact of datasets on the research of crop disease image recognition,this study used different deep neural network frameworks to study and compare the effects of different datasets in crop disease image recognition based on transfer *** selected datasets include PlantVillage and Image Database for Agricultural Diseases and Pests Research(IDADP),which have been widely used in recent *** the selected deep neural network frameworks include ResNet50,InceptionV3,and *** the method of this study,the datasets are preprocessed first,such as data *** dividing the auxiliary domain and the target domain,the selected deep neural network frameworks are used to pre-train the model on the auxiliary domain ***,the parameter-based transfer learning method was used to construct the corresponding crop disease recognition model in the *** the experiments,multiple different datasets and different models were tested and *** results show that when the test set samples and training sample scenarios are consistent,the recognition accuracy of different network frameworks on multiple test sets is generally *** the scenarios of test set samples and training samp

关键词： crop diseases datasets transfer learning deep learning image recognition

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Numerical Simulation Study on Influence of Equation of State on Internal Flow Field and Performance of S-CO_(2)Compressor

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Journal of Thermal Science 2024年第3期33卷 888-898页

作者： ZHANG lei YANG Zhenyu SUN Enhui ZHANG Qian AN Guangyao yuan Wei Hebei Key Laboratory of Low Carbon and High Efficiency Power Generation Technology North China Electric Power UniversityBaoding071003China School of Energy Power&Mechanical EngineeringNorth China Electric Power UniversityBaoding071028China

The low power consumption of the near-critical compressor is the key factor for the high efficiency of supercritical CO_(2)Brayton *** the numerical simulation of the compressor,the rapid changes in the thermophysical properties of the CO_(2)near the critical point make it difficult to capture the condensation *** paper investigates the influence of fluid physical properties on the condensation ***,the differences in the physical properties of CO_(2)in the SRK EOS(equation of state),PR EOS,and SW EOS are ***,the simulation of nozzles and compressors were carried out and *** show that the condensation positions predicted by the three EOSs are basically the *** with SW EOS,the disparities between the maximum condensation mass fraction predicted by the PR and SRK EOSs is5.7%and 11.5%,and that of total pressure ratio is 0.3%and 3.8%,*** results show that PR EOS can be considered for numerical simulation in engineering *** its physical property calculation results are closer to the actual physical properties while the physical properties change more gently,it has considerable accuracy and numerical stability.

关键词： supercritical carbon dioxide equation of state centrifugal compressor numerical simulation condensation

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