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Cell Consistency Evaluation method Based on Multiple Unsupervised Learning Algorithms

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Big Data Mining and Analytics 2024年第1期7卷 42-54页

作者： Jiang Chang Xianglong Gu Jieyun Wu Debu Zhang Stellantis China Technology center Shanghai 200233China

Unsupervised learning algorithms can effectively solve sample *** address battery consistency anomalies in new energy vehicles,we adopt a variety of unsupervised learning algorithms to evaluate and predict the battery consistency of three vehicles using charging fragment data from actual operating *** extract battery-related features,such as the mean of maximum difference,standard deviation,and entropy of batteries and then apply principal component analysis to reduce the dimensionality and record the amount of preserved *** then build models through a collection of unsupervised learning algorithms for the anomaly detection of cell consistency *** also determine whether unsupervised and supervised learning algorithms can address the battery consistency problem and document the parameter tuning *** addition,we compare the prediction effectiveness of charging and discharging features modeled individually and in combination,determine the choice of charging and discharging features to be modeled in combination,and visualize the multidimensional data for fault *** results show that the unsupervised learning algorithm is effective in visualizing and predicting vehicle core conformance faults,and can accurately predict faults in real ***“distance+boxplot”algorithm shows the best performance with a prediction accuracy of 80%,a recall rate of 100%,and an F1 of *** proposed approach can be applied to monitor battery consistency faults in real time and reduce the possibility of disasters arising from consistency faults.

关键词： battery consistency charging segment data unsupervised learning

Satellite anomaly detection based on reconstruction discrepancy theory utilizing a new dual-branch reconstruction model

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Science China Technological Sciences 2024年第10期67卷 3294-3307页

作者： ZHAO HaoTian QIU Shi LIU Ming CAO XiBin Research center of Satellite Technology School of AstronauticsHarbin Institute of Technology

To enhance the accuracy of deep learning methods based on reconstruction discrepancy in satellite anomaly detection tasks, this study proposes a dual-branch reconstruction model(DBRM) and designs a comprehensive satellite anomaly detection framework around this model. Firstly, we introduce the temporal-channel mixer(TC-Mixer) module, which mainly comprises a self-attention layer for capturing long-range temporal dependencies in telemetry data, and two types of feed-forward networks(FFN) for extracting complex patterns in the temporal and channel dimension of telemetry data. This design endows the TC-Mixer module with robust capabilities for extracting complicated dependencies in telemetry data. Secondly, with the TC-Mixer module as the main component, we designed the DBRM. This model utilizes a shared latent representation layer, allowing the regeneration branch and forecasting branch of the DBRM to share most of the feature extraction network architecture. This approach significantly enhances the model's regression accuracy while reducing computational complexity. Thirdly, using the DBRM as the core network model, we devised a comprehensive satellite anomaly detection framework. This includes an anomaly criterion that considers the reconstruction discrepancy of both the regeneration and forecasting branches, the peak-over-threshold(POT) method for anomaly thresholding, and the MIC-based feature engineering method, etc. Finally, we conducted comparative experiments with several SOTA anomaly detection algorithms on two public and one private satellite anomaly detection datasets. The experimental results validate the effectiveness and superiority of our proposed method.

关键词： anomaly detection reconstruction discrepancy dual-branch reconstruction model (DBRM) satellite telemetry data time series

Self-dispersed molybdenum disulfide quantum dot/graphene crumpled ball as efficient high temperature lubricant additive

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Friction 2024年第8期12卷 1771-1784页

作者： Guiru DU Yujuan ZHANG Shuguang FAN Ningning SONG Shengmao ZHANG Pingyu ZHANG Engineering Research center for Nanomaterials Henan UniversityKaifeng 475004China

Inorganic nanoparticles have been proved as powerful lubricant additives at elevated ***,the tribological properties are inevitably impaired due to poor dispersion and insufficient high temperature resistance of organic matter modified ***,we prepare a self-dispersed molybdenum disulfide quantum dot/graphene crumpled ball(MGCB)comprising molybdenum disulfide quantum dot uniformly interspersed on the wrinkled graphene *** crumpled ball composite possesses excellent dispersity in polyalkylene glycol base oil without depending on surface *** with the conventional phosphate esters lubricant,our results indicate MGCB could vastly improve the lubrication performance of polyalkylene glycol with an extremely low concentration(0.05 wt%)at elevated temperature(150°C),showing a friction reduction of 47%and a wear reduction of 30%compared with the conventional phosphate esters lubricant(tricresyl phosphate,TCP).This is because crumpled ball potentiates synergistic lubrication effect within the boundary ***,we envision our designed self-dispersed MGCB has significant potential in tribological application at elevated temperature.

关键词： self-dispersed crumpled ball graphene molybdenum disulfide quantum dot high temperature tribological properties

Controlled synthesis of one-dimensional segmented heteronanostructures

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Science China Materials 2024年第8期67卷 2715-2716页

作者： Zhiyong Tang CAS Key Laboratory of Nanosystem and Hierarchical Fabrication CAS Center for Excellence in NanoscienceNational Center for Nanoscience and TechnologyBeijing 100190China

Telluride materials possess distinctive advantages,including the high theoretical volume capacity and electrical conductivity,rendering them promising candidates for a range of energy storage and optoelectronic applications[1].Heterogeneous compositions and interfaces in heteronanostructures have significant implications on the electron transport,magnetic coupling,and phonon scattering,thereby promoting the performances in photocatalysis,and thermoelectrics[2].

关键词： synthesis rendering thereby

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Movement Trend Alterations in the Periaqueductal Gray(PAG)-Employed Ratbot Navigation Are Correlated with Stimulation Parameters

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Journal of Bionic Engineering 2024年第2期21卷 866-876页

作者： Sina Khajei Abed Khorasani Mohammad Reza Afarinesh Vahid Sheibani Neuroscience Research center Institute of NeuropharmacologyKerman University of Medical SciencesKerman***Iran Cognitive Neuroscience Research center Institute of NeuropharmacologyKerman University of Medical SciencesKerman***Iran

In previous studies,Periaqueductal Gray(PAG)stimulation was used to stop ratbots from *** to the homology between the PAG and the intercollicular nucleus,which has been used for forward movement in birds,we investigated the possibility of PAG application to induce forward locomotion for the first *** a corridor maze,the traveled distances via PAG electrical stimulation were examined in nine Wistar male rats during three sessions.A custom-designed stimulator was developed to apply the *** results showed reductions in responses to stimulation over ***,the traveled distances had negative slopes during the consecutive trials(in 8 out of the 9 rats),and the slope mean was significantly different from *** was a strong correlation between the stimulation parameters(electric Charge per Phase(CPP)and the Number of Pulses(NP))and the observed *** negative Movement Slopes(MS)were highly correlated with the CPP and the NP,as the Pearson's linear correlation coefficients were−0.87 and−0.79,*** MS-CPP coefficients of determination(R-squared)were also between 0.76 and *** addition,the MS-NP coefficients of determination were between 0.63 and ***,it is concluded that the electrical stimulation parameters influence the behavioral outcomes ***,the PAG area may be considered a suitable candidate for forward locomotion control in the future if the area is harnessed effectively to prevent undesirable chaotic behaviors.

关键词： Periaqueductal Gray(PAG) Navigation Ratbot Animal-robot Forward locomotion Movement slope

Solid polymer electrolyte-based high areal capacity all-solid-state batteries enabled with ceramic interlayers

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Nano Research 2024年第10期17卷 8803-8808页

作者： Chenji Hu Daiqian Chen Yage Huang Guoyong Xue Xi Liu Jingshu Wang Jun Ma Bowen Chen Qi Chen Linsen Li Yanbin Shen Liwei Chen School of Chemistry and Chemical Engineering in-situ Center for Physical SciencesShanghai Electrochemical Energy Device Research Center(SEED)and Frontiers Science Center for Transformative MoleculesShanghai Jiao Tong UniversityShanghai 200240China i-Lab CAS Center for Excellence in NanoscienceSuzhou Institute of Nano-Tech and Nano-Bionics(SINANO)Chinese Academy of SciencesSuzhou 215123China IDONANO Co Ltd Shanghai 201614China Future Battery Research center Global Institute of Future TechnologyShanghai Jiao Tong UniversityShanghai 200240China

Solid polymer electrolytes(SPEs)based all-solid-state batteries(ASSBs)have attracted extensive attention as a promising candidate for next-generation energy storage *** ASSBs require high fabrication pressure to achieve high areal capacity,under which,however,SPEs struggle and risk damage or failure due to their low mechanical *** is also a lack of study on complex stress and strain SPEs experience during ASSB cell assembly ***,ceramic solid electrolytes are selected as interlayers to address the stress-strain conditions during *** a result,high areal capacity ASSBs with a LiCoO2 loading of 12 mg·cm^(-2) were assembled with SPE-based composite *** 200 cycles were carried out for these cells at a current density of 1 mA·cm^(-2) under room *** capacity decay of the battery at 200 cycles is observed to be as low as 0.06% per *** work identifies a critical issue for application of SPEs in ASSBs and provides a potential strategy for the design of SPE-based ASSBs with high specific energy and long cycle life.

关键词： all-solid-state batteries ceramic interlayer solid polymer electrolyte high areal capacity

Time-sensitive prediction of NO_(2) concentration in China using an ensemble machine learning model from multi-source data

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Journal of Environmental Sciences 2024年第3期137卷 30-40页

作者： Chenliang Tao Man Jia Guoqiang Wang Yuqiang Zhang Qingzhu Zhang Xianfeng Wang Qiao Wang Wenxing Wang Big Data Research center for Ecology and Environment Environment Research InstituteShandong UniversityQingdao 266237China Shandong Provincial Eco-environment Monitoring center Jinan 250101China

Nitrogen dioxide(NO_(2))poses a critical potential risk to environmental quality and public health.A reliable machine learning(ML)forecasting framework will be useful to provide valuable information to support government *** on the data from1609 air quality monitors across China from 2014-2020,this study designed an ensemble ML model by integrating multiple types of spatial-temporal variables and three sub-models for time-sensitive prediction over a wide *** ensemble ML model incorporates a residual connection to the gated recurrent unit(GRU)network and adopts the advantage of Transformer,extreme gradient boosting(XGBoost)and GRU with residual connection network,resulting in a 4.1%±1.0%lower root mean square error over XGBoost for the test *** ensemble model shows great prediction performance,with coefficient of determination of 0.91,0.86,and 0.77 for 1-hr,3-hr,and 24-hr averages for the test results,*** particular,this model has achieved excellent performance with low spatial uncertainty in Central,East,and North China,the major site-dense *** the interpretability analysis based on the Shapley value for different temporal resolutions,we found that the contribution of atmospheric chemical processes is more important for hourly predictions compared with the daily scale predictions,while the impact of meteorological conditions would be ever-prominent for the *** with existing models for different spatiotemporal scales,the present model can be implemented at any air quality monitoring station across China to facilitate achieving rapid and dependable forecast of NO_(2),which will help developing effective control policies.

关键词： Air quality prediction Deep learning Ensemble method Nitrogen dioxide Spatiotemporal covariates

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Retrieval of Volcanic Sulfate Aerosols Optical Parameters from AHI Radiometer Data

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Advances in Atmospheric Sciences 2024年第10期41卷 1953-1968页

作者： Andrei FILEI Olga GIRINA Aleksei SOROKIN Far-Eastern center of State Research center for Space Hydrometeorology 《Planeta》 Institute of Volcanology and Seismology Far Eastern Branch of the Russian Academy of Sciences Computing center of the Far Eastern Branch of the Russian Academy of Sciences

This paper presents a method for retrieving optical parameters from volcanic sulfate aerosols from the AHI radiometer on board the Himawari-8 satellite. The proposed method is based on optical models for various mixtures of aerosol components from volcanic clouds, including ash particles, ice crystals, water drops, and sulfate aerosol droplets. The application of multi-component optical models of various aerosol compositions allows for the optical thickness and mass loading of sulfate aerosol to be estimated in the sulfuric cloud formed after the Karymsky volcano eruption on 3 November 2021. A comprehensive analysis of the brightness temperatures of the sulfuric cloud in the infrared bands was performed,which revealed that the cloud was composed of a mixture of sulfate aerosol and water droplets. Using models of various aerosol compositions allows for the satellite-based estimation of optical parameters not only for sulfate aerosol but also for the whole aerosol mixture.

关键词： H2SO4 Himawari-8 mass loading optical thickness the Karymsky volcano volcanic ash volcano

The Combined Effects of High Temperatures and Ozone Pollution on medical Emergency Calls—Jinan City,Shandong Province,China,2013–2019

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China CDC weekly 2024年第2期6卷 30-35,I0001-I0007页

作者： Huiyun Chang Chong Liu Xingyi Geng Xiumiao Peng Ke Huang Liheng Wang Liangliang Cui Department of Scientific Research and Education Jinan Municipal Center for Disease Control and PreventionJinan Municipal Center for Disease Control and Prevention Affiliated to Shandong UniversityJinan CityShandong ProvinceChina Jinan Health Well Development center Jinan CityShandong ProvinceChina Department of Environmental Health Jinan Municipal Center for Disease Control and PreventionJinan CityShandong ProvinceChina Department of Emergency Jinan Medical Emergency CenterJinan CityShandong ProvinceChina

What is already known about this topic?Studies have extensively documented the separate and independent effects of extreme temperature and ozone on morbidity and mortality associated with respiratory and circulatory *** is added by this report?The study revealed a significant association between elevated temperature,ozone pollution,and the combined effect of high temperature and ozone pollution with an increased risk of all-cause medical emergency calls(meCs)and meCs specifically related to neurological *** are the implications for public health practice?Interventional measures should be implemented to mitigate exposure to high temperatures and ozone ***,during the warm season,it is crucial for relevant authorities to focus on disseminating scientific information regarding the health impacts of elevated temperatures and ozone ***,timely public health advisories should be issued to alert the public effectively.

关键词： ozone elevated pollution