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A Novel Method for Aging Prediction of Railway Catenary Based on Improved Kalman Filter

Structural Durability & Health Monitoring 2024年第1期18卷 73-90页

作者： jie li Rongwen Wang Yongtao Hu Jinjun li School of Electrical Engineering and Automation Henan Institute of TechnologyXinxiang453003China Technology Center Sichuan Injet Electric Co.Ltd.Deyang618000China Embedded System Research Institute Xinxiang Engineering Research Center for Intelligent Condition Monitoring of MachineryXinxiang453003China

The aging prediction of railway catenary is of profound significance for ensuring the regular operation of electrified trains.However,in real-world scenarios,accurate predictions are challenging due to various interferences.This paper addresses this challenge by proposing a novel method for predicting the aging of railway catenary based on an improved Kalman filter(KF).The proposed method focuses on modifying the priori state estimate covariance and measurement error covariance of the KF to enhance accuracy in complex environments.By comparing the optimal displacement value with the theoretically calculated value based on the thermal expansion effect of metals,it becomes possible to ascertain the aging status of the catenary.To improve prediction accuracy,a railway catenary aging prediction model is constructed by integrating the Takagi-Sugeno(T-S)fuzzy neural network(FNN)and KF.In this model,an adaptive training method is introduced,allowing the FNN to use fewer fuzzy rules.The inputs of the model include time,temperature,and historical displacement,while the output is the predicted displacement.Furthermore,the KF is enhanced by modifying its prior state estimate covariance and measurement error covariance.These modifications contribute to more accurate predictions.Lastly,a low-power experimental platform based on FPGA is implemented to verify the effectiveness of the proposed method.The test results demonstrate that the proposed method outperforms the compared method,showcasing its superior performance.

关键词： Railway catenary Takagi-Sugeno fuzzy neural network Kalman filter aging prediction

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Application of multi-algorithm ensemble methods in high-dimensional and small-sample data of geotechnical engineering:A case study of swelling pressure of expansive soils

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Journal of Rock Mechanics and Geotechnical Engineering 2024年第5期16卷 1896-1917页

作者： Chao li Lei Wang jie li Yang Chen School of Urban Railway Transportation Shanghai University of Engineering ScienceShanghai201620China Discipline of Civil and Infrastructure Engineering RMIT UniversityMelbourne3001Australia School of Naval Architecture and Civil Engineering Shanghai Jiao Tong UniversityShanghai200240China

Geotechnical engineering data are usually small-sample and high-dimensional,which brings a lot of challenges in predictive modeling.This paper uses a typical high-dimensional and small-sample swell pressure(P_(s))dataset to explore the possibility of using multi-algorithm hybrid ensemble and dimensionality reduction methods to mitigate the uncertainty of soil parameter prediction.Based on six machine learning(ML)algorithms,the base learner pool is constructed,and four ensemble methods,Stacking(SG),Blending(BG),Voting regression(VR),and Feature weight linear stacking(FWL),are used for the multi-algorithm ensemble.Furthermore,the importance of permutation is used for feature dimensionality reduction to mitigate the impact of weakly correlated variables on predictive modeling.The results show that the proposed methods are superior to traditional prediction models and base ML models,where FWL is more suitable for modeling with small-sample datasets,and dimensionality reduction can simplify the data structure and reduce the adverse impact of the small-sample effect,which points the way to feature selection for predictive modeling.Based on the ensemble methods,the feature importance of the five primary factors affecting P_(s) is the maximum dry density(31.145%),clay fraction(15.876%),swell percent(15.289%),plasticity index(14%),and optimum moisture content(13.69%),the influence of input parameters on P_(s) is also investigated,in line with the findings of the existing literature.

关键词： Expansive soils Swelling pressure Machine learning(ML) Multi-algorithm ensemble Sensitivity analysis

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Cleaner production of 3.5 valent vanadium electrolyte from ammonium metavanadate by ammonia reduction-sulfuric acid dissolution method

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Tungsten 2024年第3期6卷 555-560页

作者： Cheng Wang Lan-jie li Hao Du College of Chemical Engineering University of Chinese Academy of Sciences Institute of Process Engineering National Engineering Research Center of Green Recycling for Strategic Metal Resources Chinese Academy of Sciences Hesteel Group Company limited

The vanadium redox flow battery(VRFB) has been widely used in large-scale energy storage areas due to the advantages of long lifespan and high safety. However, the high preparation cost of vanadium electrolyte limits ...

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Elevated CO_(2) increases soil redox potential by promoting root radial oxygen loss in paddy field

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Journal of Environmental Sciences 2024年第2期136卷 11-20页

作者： jie li Han Zhang Wenyi Xie Cheng liu Xiaoyu liu Xuhui Zhang lianqing li Genxing Pan Institute of Resource Ecosystem and Environment of AgricultureNanjing Agricultural UniversityNanjing 210095China College of Agriculture Nanjing Agricultural UniversityNanjing 210095China

Soil redox potential(Eh)plays an important role in the biogeochemical cycling of soil nutrients.Whereas its effect soil process and nutrients'availability under elevated atmospheric CO_(2) concentration and warming has seldom been investigated.Thus,in this study,a field experiment was used to elucidate the effect of elevated CO_(2) concentration and warming on soil Eh,redox-sensitive elements and root radial oxygen loss(ROL).We hypothesized elevated CO_(2) and warming could alter soil Eh by promoting or inhibiting ROL.We found that soil Eh in the rhizosphere was significantly higher than that of non-rhizosphere.Elevated CO_(2) enhanced soil Eh by 11.5%,which corresponded to a significant decrease in soil Fe^(2+)and Mn^(2+)concentration.Under elevated CO_(2),the concentration of Fe^(2+)and Mn^(2+)decreased by 14.7%and 13.7%,respectively.We also found that elevated CO_(2) altered rice root aerenchyma structure and promoted rice root ROL.Under elevated CO_(2),rice root ROL increased by 79.5%and 112.2%for Yangdao 6 and Changyou 5,respectively.Warming had no effect on soil Eh and rice root ROL.While warming increased the concentration of Mn^(2+)and SO_(4)^(2-)by 4.9%and 19.3%,respectively.There was a significant interaction between elevated CO_(2) and warming on Fe^(2+)and Mn^(2+).Under elevated CO_(2),warming had no effect on the concentration of Fe^(2+)but decreased Mn^(2+)concentration significantly.Our study demonstrated that elevated atmospheric CO_(2) in the future could increase soil Eh by promoting rice root ROL,which will alter some soil nutrients'availability,such as Fe^(2+)and Mn^(2+).

关键词： Atmospheric CO_(2)enrichment Global warming Soil redox potential FACE Rice root aerenchyma

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Optimization Study of Active-Passive Heating System Parameters in Village Houses in the Southern Xinjiang Province

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Energy Engineering 2024年第7期121卷 1963-1990页

作者： Xiaodan Wu jie li Yongbin Cai Sihui Huang College of Water Conservancy&Architectural Engineering Shihezi UniversityShihezi823000China Scientific Research Department Shihezi UniversityShihezi823000China

Aiming at the problems of large energy consumption and serious pollution of winter heating existing in the rural buildings in Southern Xinjiang,a combined active-passive heating system was proposed,and the simulation software was used to optimize the parameters of the system,according to the parameters obtained from the optimization,a test platform was built and winter heating test was carried out.The simulation results showed that the thickness of the air layer of 75 mm,the total area of the vent holes of 0.24 m^(2),and the thickness of the insulation layer of 120 mm were the optimal construction for the passive part;solar collector area of 28 m^(2),hot water storage tank volume of 1.4 m3,mass flow rate of 800 kg/h on the collector side,mass flow rate of 400 kg/h on the heat exchanger side,and output power of auxiliary heat source of 5∼9 kWwere the optimal constructions for active heating system.Test results showed that during the heating period,the system could provide sufficient heat to the room under different heating modes,and the indoor temperature reached over 18°C,which met the heating demand.The economic and environmental benefits of the system were analyzed,and the economic benefits of the systemwere better than coal-fired heating,and the CO_(2) emissionswere reduced by 3,292.25 kg compared with coalfiredheating.The results of the study showed that the combinedactive-passiveheating systemcouldeffectively solve the heating problems existing in rural buildings in Southern Xinjiang,and it also laid the theoretical foundation for the popularization of the combined heating systems.

关键词： Trombe wall biomass boilers active-passive combined heating systems parameter optimization villages and towns

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Phosphatidic acid-enabled MKL1 contributes to liver regeneration:Translational implication in liver failure

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Acta Pharmaceutica Sinica B 2024年第1期14卷 256-272页

作者： Jiawen Zhou Xinyue Sun Xuelian Chen Huimin liu Xiulian Miao Yan Guo Zhiwen Fan jie li Yong Xu Zilong li State Key Laboratory of Natural Medicines Department of PharmacologyChina Pharmaceutical UniversityNanjing 211198China Institute of Biomedical Research Liaocheng UniversityLiaocheng 252200China Department of Pathology Affiliated Nanjing Drum Tower Hospital of Nanjing University Medical SchoolNanjing 210008China Department of Infectious Diseases Nanjing Drum Tower Hospital Affiliated with Nanjing University Medical SchoolNanjing 210008China Institute of Viruses and Infectious Diseases Nanjing UniversityNanjing 210008China

liver regeneration following injury aids the restoration of liver mass and the recovery of liver function.In the present study we investigated the contribution of megakaryocytic leukemia 1(MKL1),a transcriptional modulator,to liver regeneration.We report that both MKL1 expression and its nuclear translocation correlated with hepatocyte proliferation in cell and animal models of liver regeneration and in liver failure patients.Mice with MKL1 deletion exhibited defective regenerative response in the liver.Transcriptomic analysis revealed that MKL1 interacted with E2F1 to program pro-regenerative transcription.MAPKAPK2 mediated phosphorylation primed MKL1 for its interaction with E2F1.Of interest,phospholipase d2 promoted MKL1 nuclear accumulation and liver regeneration by catalyzing production of phosphatidic acid(PA).PA administration stimulated hepatocyte proliferation and enhanced survival in a MKL1-dependent manner in a pre-clinical model of liver failure.Finally,PA levels was detected to be positively correlated with expression of pro-regenerative genes and inversely correlated with liver injury in liver failure patients.In conclusion,our data reveal a novel mechanism whereby MKL1 contributes to liver regeneration.Screening for small-molecule compounds boosting MKL1 activity may be considered as a reasonable approach to treat acute liver failure.

关键词： liver failure liver regeneration Transcription regulation Transcription factor Hepatocytes Phosphatidic acid Phospholipase d2 Translational medicine

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Primary Amebic Meningoencephalitis Caused by Naegleria fowleri in China: A Case Report

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Infectious Microbes & Diseases 2024年第1期6卷 43-45页

作者： Qihuan Wu Chensong Chen jie li Xiang lian Department of Infectious Diseases The Affiliated Xiangshan Hospital of Wenzhou Medical UniversityNingboChina Department of Critical Care Medicine The Affiliated Xiangshan Hospital of Wenzhou Medical UniversityNingboChina Laboratory Medicine The Affiliated Xiangshan Hospital of Wenzhou Medical UniversityNingboChina

Naegleria fowleri is a thermophilic,free-living ameba that is commonly known as the“brain-eating ameba.”This parasite invades the central nervous system and causes an acute fulminant infection,which results in a fatal form of primary amebic meningoencephalitis(PAM).Here,we report a case of PAM by an unexpected transmission route.Regrettably,the patient deteriorated swiftly and passed away subsequent to diagnosis,despite our exhaustive efforts.Here,we compiled a summary of 11 cases of PAM survivors who have all been treated with amphotericin,rifampicin and triazoles.Beside this regimen,miltefosine was also used successfully to treat PAM in an adolescent.More precise understanding of the survival rate and contributing factors can be established with further validation on ad-ditional cases.

关键词： Naegleria fowleri primary amebic meningoencephalitis metagenomic next-generation sequencing

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Associations of heavy metal mixtures with blood pressure among U.S.adults in NHANES 2017-2018 by four statistical models

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Chinese Medical Journal 2024年第5期137卷 628-630页

作者： Luli Wu Shixuan Zhang Junrou Zhang Ye Xin Piye Niu jie li Department of Occupational and Environmental Health School of Public HealthCapital Medical UniversityBeijing 100069China Beijing Key Laboratory of Environmental Toxicology School of Public HealthCapital Medical UniversityBeijing 100069China Department of Nutrition Beijing Chaoyang HospitalCapital Medical UniversityBeijing 100020China

To the Editor:Hypertension is one of the leading risk factors for cardiovascular disease and affects approximately 30%of the adult population.^([1,2])Environmental heavy metal pollution is an important public health concern.Toxic metals may increase the risk of hypertension or other cardiovascular diseases,even beyond the influence of conventional behavioral risk factors.^([3])Meanwhile certain essential trace elements,such as selenium,zinc,and iron,are involved in various enzyme reactions directly related to blood pressure regulation and are beneficial to the human body within a specific range.^([4])The analysis of health outcomes specific to metal mixtures is challenging by nonlinear relationships and interactions between toxic metals and essential trace elements.^([5])The development of innovative statistical methods for analyzing mixtures has greatly facilitated the exploration of the health effects of multiple pollutant exposures,such as Bayesian kernel machine regression(BKMR)and quantile g-computation(QG-C).

关键词： cardiovascular diseases mixtures

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Serviceability evaluation of water supply networks under seismic loads utilizing their operational physical mechanism

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Earthquake Engineering and Engineering Vibration 2022年第1期21卷 283-296页

作者： Miao Huiquan li jie Key Laboratory of Urban Security and Disaster Engineering of China Ministry of Education Beijing University ofTechnologyBeijing 100124China State Key Laboratory of Disaster Reduction in Civil Engineering Tongji UniversityShanghai 200092China Department of Structural Engineering Tongji UniversityShanghai 200092China

The serviceability of water supply networks(WSNs)under seismic loads has significant importance for estimating the probable losses and the impact of diminished functionality on affected communities.The innovation presented in this paper is suggesting a new strategy to evaluate the seismic serviceability of WSNs,utilizing their operational physical mechanism.On one hand,this method can obtain the seismic serviceability of each node as well as entire WSNs.On the other hand,this method can dynamically reflect the propagation of randomness from ground motions to WSNs.First,a finite element model is established to capture the seismic response of buried pipe networks,and a leakage model is suggested to obtain the leakage area of WSNs.Second,the transient flow analysis of WSNs with or without leakage is derived to obtain dynamic water flow and pressure.Third,the seismic serviceability of WSNs is analyzed based on the probability density evolution method(PDEM).Finally,the seismic serviceability of a real WSN in Mianzhu city is assessed to illustrate the method.The case study shows that randomness from the ground motions can obviously affect the leakage state and the probability density of the nodal head during earthquakes.

关键词： water supply networks seismic serviceability nodal water pressure stochastic ground motions probability density evolution method

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S-,P-stabilized bromoallenes for modular allenylborylation of alkenes

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Science China Chemistry 2024年第1期67卷 360-367页

作者： Jixin Wang Donghao Luo Ying Hu Zhili Duan Jianlin Yao Konstantin Karaghiosoff jie li Key Laboratory of Organic Synthesis of Jiangsu Province Suzhou Key Laboratory of Pathogen Bioscience and Anti-infective MedicineCollege of ChemistryChemical Engineering and Materials ScienceSoochow UniversitySuzhou 215123China Department Chemie Ludwig-Maximilians-Universitat MunchenButenandtstr.5-13Haus F81377 MunichGermany State Key Laboratory and Institute of Elemento-Organic Chemistry Haihe Laboratory of Sustainable Chemical TransformationsCollege of ChemistryNankai UniversityTianjin 300071China

Simultaneously forming a carbon-carbon and a carbon-heteroatom bond in a single step through transition metal-catalyzed alkene difunctionalization strategy has emerged as a powerful tool for synthetic organic chemistry.Due to the uncontrollable reactivity,direct cross-coupling with bromoallenes as the building blocks for the selective allenation and borylation remains challenging.We herein report a new type of S-and P-stabilized bromoallenes for palladium-catalyzed modular allenation and borylation of alkenes to the divergent synthesis of multiply functionalized allenes in a highly regio-and diastereoselective manifold.The reaction features broad substrate scope and wide functional group compatibility,thus providing a straightforward method to install allenyl and boryl groups across alkenes.Control experiments highlight the crucial importance of S-,P-stabilization for the oxidative insertion of Pd-species into the allenyl-Br bond.The facile syntheses of bioactive allenic steroids and exocyclic allenes demonstrate the synthetic utility of this protocol.

关键词： alkene difunctionalization olefins bromoallenes allenylborylation palladium

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