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Engine Misfire Fault Detection Based on the Channel Attention Convolutional Model

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Computers, Materials & Continua 2025年第1期82卷 843-862页

作者： Feifei yu Yongxian Huang Guoyan chen Xiaoqing Yang Canyi Du Yongkang Gong School of Mechatronic Engineering Guangdong Polytechnic Normal UniversityGuangzhou510665China School of Automotive and Transportation Engineering Guangdong Polytechnic Normal UniversityGuangzhou510665China

To accurately diagnosemisfire faults in automotive engines,we propose a Channel Attention Convolutional Model,specifically the Squeeze-and-Excitation Networks(SENET),for classifying engine vibration signals and precisely pinpointing misfire *** the experiment,we established a total of 11 distinct states,encompassing the engine’s normal state,single-cylinder misfire faults,and dual-cylinder misfire faults for different *** collection was facilitated by a highly sensitive acceleration signal collector with a high sampling rate of 20,*** collected data were methodically divided into training and testing sets based on different experimental groups to ensure generalization and prevent overlap between the two *** results revealed that,with a vibration acceleration sequence of 1000 time steps(approximately 50 ms)as input,the SENET model achieved a misfire fault detection accuracy of 99.8%.For comparison,we also trained and tested several commonly used models,including Long Short-Term Memory(LSTM),Transformer,and Multi-Scale Residual Networks(MSRESNET),yielding accuracy rates of 84%,79%,and 95%,*** underscores the superior accuracy of the SENET model in detecting engine misfire faults compared to other ***,the F1 scores for each type of recognition in the SENET model surpassed 0.98,outperforming the baseline *** analysis indicated that the misclassified samples in the LSTM and Transformer models’predictions were primarily due to intra-class misidentifications between single-cylinder and dual-cylinder misfire *** delve deeper,we conducted a visual analysis of the features extracted by the LSTM and SENET models using T-distributed Stochastic Neighbor Embedding(T-SNE)*** findings revealed that,in the LSTMmodel,data points of the same type tended to cluster together with significant ***,in the SENET model,data points of various types were more widely and evenly dispersed,demonstra

关键词： Channel attention SENET model engine misfire fault fault detection

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老年人群医疗服务利用公平性影响因素研究

中国卫生政策研究 2017年第2期10卷 74-80页

作者：赵杨冯宇彤陈琳陈娟北京大学公共卫生学院北京100191

目的:分析中国老年人医疗服务利用的公平性问题及其影响因素。方法:利用CHARLS 2013年全国调查数据,选取60岁及以上人群作为研究对象。通过集中指数和集中曲线分析老年人医疗服务利用是否存在不公平问题;通过集中指数分解法分析老年人... 详细信息

目的:分析中国老年人医疗服务利用的公平性问题及其影响因素。方法:利用CHARLS 2013年全国调查数据,选取60岁及以上人群作为研究对象。通过集中指数和集中曲线分析老年人医疗服务利用是否存在不公平问题;通过集中指数分解法分析老年人医疗服务利用不公平的主要影响因素。结果:老年人门诊和住院服务利用的集中指数分别为0.0619和0.1050,集中曲线均位于绝对公平线的下方。通过集中指数分解法发现,对门诊服务利用集中指数贡献为正向且贡献率较大的因素为:家庭年人均消费性支出、退休金金额;贡献为负向且贡献率较大的因素为:新型农村合作医疗保险,躯体性日常生活能力PADL。对住院服务集中指数贡献为正向且贡献率较大的因素为:家庭年人均消费性支出、城镇职工基本医疗保险,贡献为负向且贡献率较大的因素为:新型农村合作医疗保险、躯体性日常生活能力PADL。门诊和住院服务利用水平的不公平指数(HI)分别为0.0739和0.1339,说明老年人门诊和住院服务利用存在不公平。结论:老年人医疗服务利用存在不公平问题,经济水平是不公平的第一位贡献因素,需要类因素、新型农村合作医疗保险可缩小不公平差距。

关键词：老年人医疗服务利用不公平

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特斯拉阀水力空化的数值研究

高校化学工程学报 2020年第4期34卷 884-889页

作者：王涛王昊文林煜琛陈珉芮钱锦远浙江大学能源工程学院化工机械研究所浙江杭州310027

为了研究特斯拉阀在反向流动时会发生的水力空化现象,基于流场仿真软件Fluent,选择标准k-ε湍流模型,针对特斯拉阀的角度、圆的半径、出半圆后的直流管长度这3个参数,采用有效空化面积对水力空化的影响进行数值分析。结果表明,角度越小... 详细信息

为了研究特斯拉阀在反向流动时会发生的水力空化现象,基于流场仿真软件Fluent,选择标准k-ε湍流模型,针对特斯拉阀的角度、圆的半径、出半圆后的直流管长度这3个参数,采用有效空化面积对水力空化的影响进行数值分析。结果表明,角度越小、圆的半径越小、出半圆后的直流道长度越小、整体空化效果越好,最终优化结果为φ=35°,R=12.28 mm,L=14.87 mm。同时,基于空化数表征的空化强度研究发现,特斯拉阀的空化效果明显优于圆形孔板空化器。研究可为特斯拉阀在水力空化以及对应的水力空化污水处理领域的应用提供积极的借鉴意义。

关键词：水力空化特斯拉阀汽含率计算流体力学

Locally Enhanced Flow and Electric Fields Through a Tip Effect for Efficient Flow‑Electrode Capacitive Deionization

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Nano-Micro Letters 2025年第2期17卷 1-17页

作者： Ziquan Wang Xiangfeng chen yuan Zhang Jie Ma Zhiqun lin Amor Abdelkader Maria‑Magdalena Titirici Libo Deng College of Chemistry and Environmental Engineering Shenzhen UniversityShenzhen 518060People’s Republic of China Research Center for Environmental Functional Materials College of Environmental Science and EngineeringTongji University1239 Siping RoadShanghai 200092People’s Republic of China Department of Chemical and Biomolecular Engineering National University of SingaporeSingapore 117585Singapore Department of Engineering Faculty of Science and TechnologyBournemouth UniversityTalbot CampusFern BarrowPooleEngland BH125BBUK Institut de Chimie de Nice UniversitéCôte d’AzurUMR CNRS 727228 Av.Valrose06108 NiceFrance Department of Chemical Engineering Imperial College LondonSouth Kensington CampusExhibition RdLondon SW72AZUK

Low-electrode capacitive deionization(FCDI)is an emerging desalination technology with great potential for removal and/or recycling ions from a range of ***,it still suffers from inefficient charge transfer and ion transport kinetics due to weak turbulence and low electric intensity in flow electrodes,both restricted by the current ***,a new tip-array current collector(designated as T-CC)was developed to replace the conventional planar current collectors,which intensifies both the charge transfer and ion transport *** effects of tip arrays on flow and electric fields were studied by both computational simulations and electrochemical impedance spectroscopy,which revealed the reduction of ion transport barrier,charge transport barrier and internal *** the voltage increased from 1.0 to 1.5 and 2.0 V,the T-CC-based FCDI system(T-FCDI)exhibited average salt removal rates(ASRR)of 0.18,0.50,and 0.89μmol cm^(-2) min^(-1),respectively,which are 1.82,2.65,and 2.48 folds higher than that of the conventional serpentine current collectors,and 1.48,1.67,and 1.49 folds higher than that of the planar current ***,with the solid content in flow electrodes increased from 1 to 5 wt%,the ASRR for T-FCDI increased from 0.29 to 0.50μmol cm^(-2) min^(-1),which are 1.70 and 1.67 folds higher than that of the planar current ***,a salt removal efficiency of 99.89%was achieved with T-FCDI and the charge efficiency remained above 95%after 24 h of operation,thus showing its superior long-term stability.

关键词： Flow-electrode Capacitive deionization Current collector Tip effect Desalination

Fabrication of carbon-supported Al2O3 nanoparticles via spontaneous cross-linking to enhance selective hydrogenation of furfural

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Journal of Energy Chemistry 2025年第1期100卷 612-620页

作者： Weiwei yu Xinbao Zhang Hongyu chen Yanan Wang Shaoguo Li Fucun chen Zhenni Liu Xiujie Li Xiangxue Zhu State Key Laboratory of Catalysis Dalian Institute of Chemical Physics Chinese Academy of Sciences

Selective hydrogenation of furfural to furfuryl alcohol is a great challenge in the hydrogenation field due to thermodynamic preference for hydrogenation of C=C over C=***,a novel Al2O3/C-u hybrid catalyst,composed of N-modified dendritic carbon networks supporting Al2O3nanoparticles,was successfully prepared via carbonizing the freeze-dried gel from spontaneous cross-linking of alginate,Al3+and *** obtained carbon-supported Al2O3hybrid catalyst has a high ratio （31%） of Al species in pentahedral-coordinated *** introduction of urea enhances the surface N content,the ratio of pyrrolic N,and specific surface area of catalyst,leading to improved adsorption capacity of C=O and the accessibility of active *** the furfural hydrogenation reaction with isopropyl alcohol as hydrogen donor,Al2O3/C-u catalyst achieved a 90%conversion of furfural with 98.0% selectivity to furfuryl alcohol,outperforming that of commercial γ-***,Al2O3/C-u demonstrates excellent catalytic stability in the recycling tests attributed to the synergistic effect of abundant weak Lewis acid sites and the anchoring effect of the carbon network on *** work provides an innovative and facile strategy for fabrication of carbon-supported Al2O3hybrid catalysts with rich AlVspecies,serving as a high selective hydrogenation catalyst through MPV reaction route.

关键词： Selective hydrogenation Furfural Furfuryl alcohol Cross-linking Carbon supported Al 2 O 3 MPV route

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可伸缩视频编码在移动互联网中的应用与实现

微电子学与计算机 2016年第12期33卷 134-138页

作者：蒋宇浩余林琛中国地质大学计算机学院湖北武汉430074

为了应对移动互联网中终端和网络的异构性,尝试将H.264/SVC应用到移动视频点播服务中,实现基于SVC的码流自适应播放系统.借助JSVM研究并实现了不同空间、时间,以及质量层的可伸缩视频的生成;基于VS模拟了可伸缩视频在传输和播放过程中... 详细信息

为了应对移动互联网中终端和网络的异构性,尝试将H.264/SVC应用到移动视频点播服务中,实现基于SVC的码流自适应播放系统.借助JSVM研究并实现了不同空间、时间,以及质量层的可伸缩视频的生成;基于VS模拟了可伸缩视频在传输和播放过程中码率的动态切换;通过分析子层码流证实了可伸缩视频具有码率跨度大及解码质量好等特点.最终验证了H.264/SVC在移动互联网视频服务中所具有的优势,以及应用的可行性.

关键词：移动互联网 H.264/SVC 码流自适应 JSVM

基于ANSYS Workbench的数控折弯机的优化设计

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组合机床与自动化加工技术 2017年第9期 132-135页

作者：毛曙宇陈林江阴职业技术学院江苏江阴214400 菲尼萨光电通讯科技有限公司江苏无锡214122

文章利用有限元方法,借助Ansys workbench 14.0,以减重为优化目标,在保证结构具有足够强度和刚度的基础上,对原有某折弯机结构分别进行了尺寸优化和拓扑优化,给出了结构的优化模型。同时,对结构中不满足强度和刚度要求的部位进行了改进... 详细信息

文章利用有限元方法,借助Ansys workbench 14.0,以减重为优化目标,在保证结构具有足够强度和刚度的基础上,对原有某折弯机结构分别进行了尺寸优化和拓扑优化,给出了结构的优化模型。同时,对结构中不满足强度和刚度要求的部位进行了改进。尺寸优化后,滑块的最大位移降低19%,最大等效应力降低44%;机架的危险部位最大等效应力降低56%,机架的质量降低了12.7%。拓扑优化后,机架的质量减轻了19.1%。折弯机的综合性能得到大幅提升。

关键词：折弯机有限元优化设计

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一种新的应用层对等路由机制的研究

微电子学与计算机 2008年第9期25卷 102-104页

作者：余林琛廖小飞中国地质大学计算机学院湖北武汉430074 华中科技大学计算机学院湖北武汉430074

提出了一种基于对等网的路由方案.该方案首先在网络中部署多个服务器,每个服务器维护一个连接其他服务器的时延二叉树,每个动态节点归属于某个服务器管辖.基于该树,任何两个动态节点能够以较小的代价快速建立通信所需的路由路径.仿真测... 详细信息

提出了一种基于对等网的路由方案.该方案首先在网络中部署多个服务器,每个服务器维护一个连接其他服务器的时延二叉树,每个动态节点归属于某个服务器管辖.基于该树,任何两个动态节点能够以较小的代价快速建立通信所需的路由路径.仿真测试结果证明了这一方案具有较好的性能.

关键词：对等计算路由延时

High-energy-density lithium manganese iron phosphate for lithium-ion batteries: Progresses, challenges, and prospects

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Journal of Energy Chemistry 2025年第1期100卷 1-17页

作者： Bokun Zhang Xiaoyun Wang Shuai Wang Yan Li Libo chen Handong Jiao Zhijing yu Jiguo Tu State Key Laboratory of Advanced Metallurgy University of Science and Technology Beijing Research Institute for Intelligent Wearable Systems The Hong Kong Polytechnic University Institute of Advanced Structure Technology Beijing Institute of Technology

The soaring demand for smart portable electronics and electric vehicles is propelling the advancements in high-energy–density lithium-ion *** manganese iron phosphate (LiMnxFe1-xPO4) has garnered significant attention as a promising positive electrode material for lithium-ion batteries due to its advantages of low cost,high safety,long cycle life,high voltage,good high-temperature performance,and high energy *** LiMnxFe1-xPO4has made significant breakthroughs in the past few decades,there are still facing great challenges in poor electronic conductivity and Li-ion diffusion,manganese dissolution affecting battery cycling performance,as well as low tap *** review systematically summarizes the reaction mechanisms,various synthesis methods,and electrochemical properties of LiMnxFe1-xPO4to analyze reaction processes accurately and guide material ***,the main challenges currently faced are concluded,and the corresponding various modification strategies are discussed to enhance the reaction kinetics and electrochemical performance of LiMnxFe1-xPO4,including multi-scale particle regulation,heteroatom doping,surface coating,as well as microscopic morphology ***,in view of the current research challenges faced by intrinsic reaction processes,kinetics,and energy storage applications,the promising research directions are *** importantly,it is expected to provide key insights into the development of high-performance and stable LiMnxFe1-xPO4materials,to achieve practical energy storage requirements.

关键词： Semiconductor doping