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Effect of temperature on tribofilm growth and the lubrication of the piston ring-cylinder liner system in two-stroke marine engines

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Friction 2024年第8期12卷 1858-1881页

作者： Xiuyi LYU Jiang HU Yunchuan WANG Jinlu SHENG Xuan MA tongyang li Chang GE Xiqun LU Chongqing Jiaotong University Chongqing 400074China Chongqing Metropolitan College of Science and Technology Chongqing 402167China Harbin Engineering University Harbin 150001China Yantai Zhongke Research Institute of Advanced Materials and Green Chemical Engineering Yantai 264006China State Key Laboratory of Solid Lubrication Lanzhou Institute of Chemical PhysicsChinese Academy of SciencesLanzhou 730000China

This study is an optimized extension based on the authors’previous research on the tribo-chemical reaction under constant temperature field of two-stroke internal combustion engines(ICEs).It establishes a coupled analysis model that considers the tribo-chemical reactions,dynamic contact,and interface lubrication of the piston ring-cylinder liner(PRCL)system under transient temperature *** this study,for the first time,the prediction of the tribofilm thickness and its influence on the surface micro-topography(the comprehensive roughness)are coupled in the working temperature field of the PRCL system,forming an effective model framework and providing a model basis and analytical basis for subsequent *** study findings reveal that by incorporating temperature and tribofilm into the simulation model,the average friction deviation throughout the stroke decreases from 8.92%to 0.93%when compared to experimental ***,the deviation during the combustion regime reduces from 39.56%to 7.34%.The proposed coupled model provides a valuable tool for the evaluation of lubrication performance of the PRCL system and supports the analysis software forward design in two-stroke ICEs.

关键词： tribofilm piston ring-cylinder liner(PRCL)system temperature comprehensive roughness two-stroke internal combustion engines(ICEs)

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An adaptive-order particle filter for remaining useful life prediction of aviation piston pumps

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Chinese Journal of Aeronautics 2018年第5期31卷 941-948页

作者： tongyang li Shaoping WANG Jian SHI Zhonghai MA School of Automation Science and Electrical Engineering Beihang University

An accurate estimation of the remaining useful life（RUL） not only contributes to an effective application of an aviation piston pump, but also meets the necessity of condition based maintenance（CBM）. For the current RUL evaluation methods, a model-based method is inappropriate for the degradation process of an aviation piston pump due to difficulties of modeling, while a data-based method rarely presents high-accuracy prediction in a long period of time. In this work,an adaptive-order particle filter（AOPF） prognostic process is proposed aiming at improving long-term prediction accuracy of RUL by combining both kinds of methods. A dynamic model is initialized by a data-driven or empirical method. When a new observation comes, the prior state distribution is approximated by a current model. The order of the current model is updated adaptively by fusing the information of the observation. Monte Carlo simulation is employed for estimating the posterior probability density function of future states of the pump＇s *** updating the order number adaptively, the method presents a higher precision in contrast with those of traditional methods. In a case study, the proposed AOPF method is adopted to forecast the degradation status of an aviation piston pump with experimental return oil flow data, and the analytical results show the effectiveness of the proposed AOPF method.

关键词： Adaptive prognosis Condition based maintenance (CBM)IPartiCle filter (PF) PiSton pump Remaining useful life (RUL)

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An energy-based coupling degradation propagation model and its application to aviation actuation system

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Chinese Journal of Aeronautics 2020年第4期33卷 1288-1298页

作者： tongyang li Shaoping WANG Jian SHI Enrico ZIO Xiaoyu CUI School of Automation Science and Electrical Engineering Beihang UniversityBeijing 100083China Energy Department Politecnico di MilanoVia La Masa 34Milano 20156Italy MINES ParisTech PSL Research UniversityCRCSophia Antipolis06410France Department of Nuclear Engineering College of EngineeringKyung Hee UniversityGyeonggi-do 12001South Korea

The degradation of components in complex mechatronic systems involves multiple physical processes which will cause coupling interactions among nodes in the *** interaction of nodes may be carried out not only by physical connections but also by the environment which cannot be described by single network using the traditional *** order to give out a unified model to quantitatively describe the coupling degradation spreading by both physical connections and environment,a novel Energy-Flow-Field Network(EFFN)and a coupling degradation model based on EFFN are proposed in this *** EFFN is driven by energy flow and the state transition of spatially related nodes is triggered by the dissipation *** application is conducted on aviation actuation system in which the degradation spreading by fluid-thermal-solid interaction is *** degradation path and the most probable fault reason can be obtained by combining the state transition and energy output of nodes,which is consistent with the given scenario.

关键词： Actuation system Cascading failure Complex system Failure propagation Mechatronic system

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Fault diagnosis of an intelligent hydraulic pump based on a nonlinear unknown input observer

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Chinese Journal of Aeronautics 2018年第2期31卷 385-394页

作者： Zhonghai MA Shaoping WANG Jian SHI tongyang li Xingjian WANG School of Automation Science and Electrical Engineering Beihang University

Hydraulic piston pumps are commonly used in aircraft. In order to improve the viability of aircraft and energy efficiency, intelligent variable pressure pump systems have been used in aircraft hydraulic systems more and more widely. Efficient fault diagnosis plays an important role in improving the reliability and performance of hydraulic systems. In this paper, a fault diagnosis method of an intelligent hydraulic pump system（IHPS） based on a nonlinear unknown input observer（NUIO） is proposed. Different from factors of a full-order Luenberger-type unknown input observer, nonlinear factors of the IHPS are considered in the NUIO. Firstly, a new type of intelligent pump is presented, the mathematical model of which is established to describe the IHPS. Taking into account the real-time requirements of the IHPS and the special structure of the pump, the mechanism of the intelligent pump and failure modes are analyzed and two typical failure modes are obtained. Furthermore, a NUIO of the IHPS is performed based on the output pressure and swashplate angle signals. With the residual error signals produced by the NUIO, online intelligent pump failure occurring in real-time can be detected. Lastly, through analysis and simulation, it is confirmed that this diagnostic method could accurately diagnose and isolate those typical failure modes of the nonlinear IHPS. The method proposed in this paper is of great significance in improving the reliability of the IHPS.

关键词： Fault diagnosis Hydraulic piston pump Model-based Nonlinear unknown input observer (NUIO) Residual error

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降雨、施肥对补水河流周边土壤硝态氮迁移分布的影响

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中国生态农业学报（中英文） 2024年第7期32卷 1206-1217页

作者：许晓媛李彤阳尹高飞杨壹泽焦会青文宏达王田甜习斌李文超河北农业大学资源与环境科学学院/省部共建华北作物改良与调控国家重点实验室/河北省农田生态环境重点实验室保定071000 河北省沧州市任丘市第四中学任丘062550 农业农村部农业生态与资源保护总站北京100125

补水河流周边土壤硝态氮迁移过程受到河流水文条件、降雨、施肥等多因素的影响,研究多种因素共同作用下土壤硝态氮分布及淋失特征,可以为深入理解土壤氮素循环过程奠定基础。本研究以华北平原白洋淀入淀河流周边农田和农林复合区(AF)为... 详细信息

补水河流周边土壤硝态氮迁移过程受到河流水文条件、降雨、施肥等多因素的影响,研究多种因素共同作用下土壤硝态氮分布及淋失特征,可以为深入理解土壤氮素循环过程奠定基础。本研究以华北平原白洋淀入淀河流周边农田和农林复合区(AF)为研究对象,其中农田区设置不施肥(CK)、优化施肥(YH)、习惯施肥(XG)3个施肥处理,综合分析在不同降雨类型、生态补水等因素作用下土壤硝态氮剖面分布、淋溶等迁移特征。研究结果表明:施氮量、降雨类型、生态补水等均是影响补水河流周边硝态氮迁移淋失的关键因子。其中,施氮量决定土壤硝态氮淋失总量(P<0.01)。随着施氮量的增加,土壤剖面的硝态氮含量和硝态氮淋失量均显著增加,与XG处理相比,YH处理和AF处理的硝态氮淋失总量分别减少40.6%和40.1%。降雨和生态补水改变了硝态氮在土壤剖面的迁移过程。其中,降雨主要影响表层土壤硝态氮向中下层迁移,生态补水主要影响中下层土壤硝态氮向更深层土壤的迁移。另外,不同降雨类型对土壤硝态氮迁移的影响有所差异,即两种降雨类型下硝态氮向下层土壤迁移速率和迁移量不同。常规降雨(3 d累积降雨65.2 mm)和强降雨(5 h累积降雨49.2 mm)两种情况下硝态氮累积峰均在40~60 cm土层。常规降雨导致XG处理40~60 cm比0~40 cm土层硝态氮储量增加9.7%;强降雨导致XG处理40~60 cm比0~40 cm土层硝态氮储量增加16.7%。生态补水导致YH处理和XG处理在100~140 cm土层硝态氮储量分别减少42.7 kg·hm^(-2)和39.6 kg·hm^(-2)。以上研究结果对于生态补水和极端降雨背景下土壤氮素污染管理具有重要意义。

关键词：施氮量常规降雨强降雨生态补水硝态氮迁移

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碳纤维/氮化硅复合陶瓷的制备及其电磁屏蔽性能研究

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陶瓷学报 2024年第4期45卷 750-759页

作者：黄浩王鲁杰齐倩汤华国李彤阳于源孙海清乔竹辉中国科学院兰州化学物理研究所甘肃兰州73000 山东科技大学山东青岛266590 烟台先进材料与绿色制造山东省实验室山东烟台264006 青岛资源化学与新材料研究中心山东青岛266000

优异的电磁屏蔽材料是保护人体健康和仪器设备正常工作必不可少的选择。通过放电等离子烧结制备含碳纤维的氮化硅基陶瓷,具备着良好电磁屏蔽性能的同时,也保持着一定的机械强度。首先,碳纤维的引入导致复合陶瓷的介电常数增加,样品表面... 详细信息

优异的电磁屏蔽材料是保护人体健康和仪器设备正常工作必不可少的选择。通过放电等离子烧结制备含碳纤维的氮化硅基陶瓷,具备着良好电磁屏蔽性能的同时,也保持着一定的机械强度。首先,碳纤维的引入导致复合陶瓷的介电常数增加,样品表面阻抗失配增强,大部分电磁波被反射。其次,高含量碳纤维的加入,在氮化硅基体中形成完整的三维导电网络骨架,复合陶瓷的电导率最高达到2.15 S·m^(-1)。入射至样品内部的电磁波被导电骨架形成的介电损耗所吸收。最后,加入7 wt.%碳纤维后,复合陶瓷的维氏硬度、断裂韧性和电磁屏蔽效能分别达到11.90 GPa、6.05 MPa·m^(1/2)和46 dB。

关键词：碳纤维氮化硅电导率电磁屏蔽

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Discussion on the Application of Highway Maintenance Platform Based on GIS + BIM Technology—Taking Gansu Province as an Example

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World Journal of Engineering and Technology 2021年第4期9卷 765-781页

作者： Juming Hao Jianbin Zhu tongyang li Ruotong li Yuanqing Wang Gansu Highway and Transportation Construction Group Co. Ltd. Lanzhou China Shenzhen Expressway Engineering Consulting Co. Ltd. Shenzhen China Chang’an University Xi’an China

Gansu Province is a large province in Western China, and its geographical location and economic status are very important. With the state’s attention to the western development, the economy of the western region rep... 详细信息

lign:justify;"> Gansu Province is a large province in Western China, and its geographical location and economic status are very important. With the state’s attention to the western development, the economy of the western region represented by Gansu Province has developed rapidly, and the construction of roads and other infrastructure has also been developed. Taking Gansu Province as an example, this paper studies and discusses the application of highway maintenance platform based on GIS + BIM Technology. Firstly, this paper expounds the advantages of GIS + BIM Technology in highway construction and maintenance, and analyzes the development status of GIS + BIM Technology;Secondly, it expounds how to solve the problem of highway maintenance from the aspects of GIS + BIM system and its advantages and difficulties in highway maintenance, and briefly explains the difficulties existing in highway maintenance in Gansu Province. Then, starting from the path of GIS + BIM Technology to solve highway maintenance in Gansu Province, this paper analyzes the expected effect of GIS + BIM Technology in highway maintenance in Gansu Province.

关键词： GIS + BIM Technology Highway Research on Maintenance Platform Gansu Province

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Discussion on the Application of Highway Maintenance Platform Based on GIS + BIM Technology——Taking Gansu Province as an Example

Discussion on the Application of Highway Maintenance Platfor...

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作者： Juming Hao Jianbin Zhu tongyang li Ruotong li Yuanqing Wang Gansu Highway and Transportation Construction Group Co. Ltd. Shenzhen Expressway Engineering Consulting Co. Ltd. Chang'an University

Gansu Province is a large province in Western China, and its geographical location and economic status are very *** the state’s attention to the western development, the economy of the western region represented by Gansu Province has developed rapidly, and the construction of roads and other infrastructure has also been *** Gansu Province as an example, this paper studies and discusses the application of highway maintenance platform based on GIS + BIM ***, this paper expounds the advantages of GIS + BIM Technology in highway construction and maintenance, and analyzes the development status of GIS + BIM Technology;Secondly, it expounds how to solve the problem of highway maintenance from the aspects of GIS + BIM system and its advantages and difficulties in highway maintenance, and briefly explains the difficulties existing in highway maintenance in Gansu ***, starting from the path of GIS + BIM Technology to solve highway maintenance in Gansu Province, this paper analyzes the expected effect of GIS + BIM Technology in highway maintenance in Gansu Province.

关键词： GIS + BIM Technology Highway Research on Maintenance Platform Gansu Province

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A review of occluded objects detection in real complex scenarios for autonomous driving

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Green Energy and Intelligent Transportation 2023年第3期2卷 65-77页

作者： Jiageng Ruan Hanghang Cui Yuhan Huang tongyang li Changcheng Wu Kaixuan Zhang Department of Materials and Manufacturing Beijing University of TechnologyBeijingChina Centre for Green Technology School of Civil and Environmental EngineeringUniversity of Technology SydneyNSW2007Australia

Autonomous driving is a promising way to future safe,efficient,and low-carbon ***-time ac-curate target detection is an essential precondition for the generation of proper following decision and control ***,considering the complex practical scenarios,accurate recognition of occluded targets is a major challenge of target detection for autonomous driving with limited computational *** reveal the overlap and difference between various occluded object detection by sharing the same available sensors,this paper presents a review of detection methods for occluded objects in complex real-driving *** the rapid development of autonomous driving technologies,the research analyzed in this study is limited to the recent five *** study of occluded object detection is divided into three parts,namely occluded vehicles,pedes-trians and traffic *** paper provided a detailed summary of the target detection methods used in these three parts according to the differences in detection methods and ideas,which is followed by the comparison of advantages and disadvantages of different detection methods for the same ***,the shortcomings and limitations of the existing detection methods are summarized,and the challenges and future development prospects in this field are discussed.

关键词： Autonomous driving Occluded objects Object detection Vehicles Pedestrians Traffic signs

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硫化氢吸收塔预洗段漏液问题及处理措施

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煤炭科学技术 2018年第S2期46卷 249-251页

作者：吴楠李通鞅山西中煤平朔能源化工有限公司山西朔州036000 中煤平朔集团公司洗选中心山西朔州036000

硫化氢吸收塔是低温甲醇洗装置的核心设备之一,其预洗段在低液量、高气量工况下工作。硫化氢吸收塔分为为脱油段和脱硫段2部分,预洗甲醇洗涤脱除微量水和轻烃(即脱油段),之后在上部用脱碳甲醇洗涤脱除硫化物(即脱硫段),针对运行中出现... 详细信息

硫化氢吸收塔是低温甲醇洗装置的核心设备之一,其预洗段在低液量、高气量工况下工作。硫化氢吸收塔分为为脱油段和脱硫段2部分,预洗甲醇洗涤脱除微量水和轻烃(即脱油段),之后在上部用脱碳甲醇洗涤脱除硫化物(即脱硫段),针对运行中出现的预洗洗涤流量失控现象,分析原因,制订处理方案并实施,对脱油段接液槽四周及支撑板位置满焊处理,满足了生产要求,对类似装置的施工、安装提供指导建议及验收标准。

关键词：低温甲醇洗硫化氢吸收塔漏液处理

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