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dynamics and stability analysis of unbalance responses in mid-positioned electrically assisted turbocharger rotor

International Journal of Mechanical system dynamics 2024年第4期4卷 515-535页

作者： Mingyue Hu Shuqian Cao Xiaolin Cao Zhiyong Zhang Rixiu Men Zhenzhen You Tianyou Wang School of Mechanical Engineering Tianjin UniversityTianjinChina Tianjin Key Laboratory of Nonlinear Dynamics and Control TianjinChina National Key Laboratory of Vehicle Power System TianjinChina Science and Technology on Diesel Engine Turbocharging Laboratory China North Engine Research InstituteTianjinChina

Electrically assisted turbochargers(EAT)improve intake efficiency by motor-assisted compressor impeller rotation,enhancing the system's transient ***,the addition of motor rotor components has increased the number of unbalanced positions in the shaft system,leading to problems such as excessive compressor end vibration and complex changes in oil film *** evaluate the effects of unbalance in the motor rotor,along with the parameters of floating ring bearings(FRB),on the dynamic response of EAT,a finite element model of an EAT rotor supported by nonlinear FRB is developed,and the vibration response of the compressor end bearing is obtained by numerical *** results indicate:(1)In contrast to the effect of compressor and turbine unbalance,proper motor rotor unbalance is more effective in suppressing oil whirl instability in the high-speed operating ***,a new inner oil film whirl“instability interval”is also induced in the low-speed operating range,leading to an increase in the Y1 compressor-end amplitude at low and medium speeds,and this“instability interval”increases with the amount of unbalance.(2)When an oil whirl occurs in the oil film,the maximum eccentricity of the bearing surges and is greater than 0.3,which can be used as an effective threshold for determining whether the oil film is unstable in engineering applications.(3)A suitable outer oil-film clearance range should be 35–40μm,otherwise,a wide range of outer oil-film whirl instability *** the amount of unbalance and oil-film clearance to suppress the subsynchronous vibration of the EAT,provides a theoretical basis for the design of the dynamics of the nonlinear rotor bearing system and improves the stability of the turbocharger's operation.

关键词： electrically assisted turbocharger motor unbalance oil-film clearance rotor dynamics nonlinear vibration

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Baseline Results for Selected Nonlinear system Identification Benchmarks

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IFAC-PapersOnLine 2024年第15期58卷 474-479页

作者： Max Champneys Gerben I. Beintema R. Tóth Maarten Schoukens Timothy J. Rogers Dynamics Research Group University of Sheffield Sheffield UK Control System group Eindhoven University of Technology Eindhoven the Netherlands Systems and Control Laboratory Institute for Computer Science and Control Budapest Hungary

Nonlinear system identification remains an important open challenge across research and academia. Large numbers of novel approaches are seen published each year, each presenting improvements or extensions to existing methods. It is natural, therefore, to consider how one might choose between these competing models. Benchmark datasets provide one clear way to approach this question. However, to make meaningful inference based on benchmark performance it is important to understand how well a new method performs comparatively to results available with well-established methods. This paper presents a set of ten baseline techniques and their relative performances on five popular benchmarks. The aim of this contribution is to stimulate thought and discussion regarding objective comparison of identification methodologies.

关键词： Nonlinear system Identification Benchmarks NARX Nonlinear State-Space

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research on data assimilation strategy of turbulent separated flow over airfoil

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Applied Mathematics and Mechanics(English Edition) 2022年第4期43卷 571-586页

作者： Ying ZHANG Lin DU Weiwei ZHANG Zichen DENG National Key Laboratory of Science and Technology on Aerodynamic Design and Research School of AeronauticsNorthwestern Polytechnical UniversityXi'an 710072China Complex System Dynamics and Control Academic Exchange Center School of Mathematics and StatisticsNorthwestern Polytechnical UniversityXi'an 710119China Rotor Aerodynamics Key Laboratory China Aerodynamics Research and Development CenterMianyang 621000Sichuan ProvinceChina

In order to increase the accuracy of turbulence field reconstruction,this paper combines experimental observation and numerical simulation to develop and establish a data assimilation framework,and apply it to the study of S809 low-speed and high-angle airfoil *** method is based on the ensemble transform Kalman filter(ETKF)algorithm,which improves the disturbance strategy of the ensemble members and enhances the richness of the initial members by screening high flow field sensitivity constants,increasing the constant disturbance dimensions and designing a fine disturbance *** results show that the pressure distribution on the airfoil surface after assimilation is closer to the experimental value than that of the standard Spalart-Allmaras(S-A)*** separated vortex estimated by filtering is fuller,and the eddy viscosity field information is more abundant,which is physically consistent with the observation ***,the data assimilation method based on the improved ensemble strategy can more accurately and effectively describe complex turbulence phenomena.

关键词： turbulence data assimilation ensemble disturbance strategy large angle of attack separation ensemble transform Kalman filter(ETKF)

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A Modified Iterative Learning control Approach for the Active Suppression of Rotor Vibration Induced by Coupled Unbalance and Misalignment

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Chinese Journal of Mechanical Engineering 2024年第1期37卷 242-253页

作者： Yifan Bao Jianfei Yao Fabrizio Scarpa Yan Li College of Mechanical and Electrical Engineering Beijing University of Chemical TechnologyBeijing 100029China State Key Laboratory of High-end Compressor and System Technology Beijing 100029China Beijing Key Laboratory of High-end Mechanical Equipment Health Monitoring and Self-Recovery Beijing University of Chemical TechnologyBeijing 100029China Key Lab of Engine Health Monitoring-Control and Networking of Ministry of Education Beijing University of Chemical TechnologyBeijing 100029China Bristol Composites Institute(ACCIS) University of BristolBristol BS81TRUK Dynamics and Control Research Group(DCRG) University of BristolBristol BS81TRUK

This paper proposes a modified iterative learning control(MILC)periodical feedback-feedforward algorithm to reduce the vibration of a rotor caused by coupled unbalance and parallel *** control of the vibration of the rotor is provided by an active magnetic actuator(AMA).The iterative gain of the MILC algorithm here presented has a self-adjustment based on the magnitude of the *** filters are adopted to extract the synchronous(1×Ω)and twice rotational frequency(2×Ω)components of the rotor *** the notch frequency of the filter and the size of feedforward storage used during the experiment have a real-time adaptation to the rotational *** method proposed in this work can provide effective suppression of the vibration of the rotor in case of sudden changes or fluctuations of the rotor *** and experiments using the MILC algorithm proposed here are carried out and give evidence to the feasibility and robustness of the technique proposed.

关键词： Rotor vibration suppression Modified iterative learning control Unbalance Parallel misalignment Active magnetic actuator

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Baseline Results for Selected Nonlinear system Identification Benchmarks

arXiv

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arXiv 2024年

作者： Champneys, Max D. Beintema, Gerben I. Tóth, Roland Schoukens, Maarten Rogers, Timothy J. Dynamics Research Group University of Sheffield Sheffield United Kingdom Control System Group Eindhoven University of Technology Eindhoven Netherlands Systems and Control Laboratory Institute for Computer Science and Control Budapest Hungary

关键词： Nonlinear simulations

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Analysis of Reviews of Tourist Objects Based on Large Language Models

Analysis of Reviews of Tourist Objects Based on Large Langua...

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Informatics, Electronics, and Radio Engineering (PIERE), International Conference Problems of

作者： Olga A. Nikolaychuk Ivan A. Poddubniy Laboratory of Information and Telecommunication Technologies for Technogenic Safety Research Siberian Branch of the Russian Academy of Sciences Matrosov Institute for System Dynamics and Control Theory (ISDCT SB RAS) Irkutsk Russia

ISBN: (数字)9798331516321

ISBN: (纸本)9798331516338

The article is devoted to solving the problem of identifying issues in the field of regional tourism. To solve this task, the method of aspect-based analysis of reviews of tourist objects using of large language models and prompt-engineering has been developed and implemented. Accommodation facilities, dining establishments, services and attractions are considered as tourist objects. The reviews are obtained from tourist information aggregators using web-scraping method. The initial dataset consisted of 1300 tourist reviews. A large language model, Saiga2, with 70 billion parameters was chosen for the implementation of prompt engineering. The problem analysis task was divided into subtasks of extracting and classifying facts (advantages and disadvantages). For each subtask, prompts have been developed with an indication of the role, a description of classes and examples of solutions. The description of classes is based on the literature analysis of issues in tourism. The method is implemented on the Yandex. Cloud platform, tested and validated to search for accommodation facilities satisfying tourist's requests for Olkhon Island. The results of the method's accuracy evaluation are described using metrics f1, micro f1, macro f1 and weighted f1. To test the proposed method validation, tests describing information about different categories of tourists were developed. The performance of the method was evaluated by comparing the solutions provided by the tourism expert and the created method implementation. The experiment showed 80 percent coincidence of the solutions. The method is planned to be implemented in the service of regional tourism monitoring of the Baikal region.

关键词： Measurement Solid modeling Sentiment analysis Reviews Large language models Natural languages Decision making Prompt engineering Informatics Monitoring

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Model Predictive control of a Hybrid VA v for Parcel Delivery Applications 1

Model Predictive Control of a Hybrid VA v for Parcel Deliver...

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1st AIRPHARO Workshop on Aerial Robotic systems Physically Interacting with the Environment, AIRPHARO 2021

作者： Konyalioglu, Turan Alnipak, Sinan Altug, Erdinc İstanbul Technical University System Dynamics and Control Graduate Program İstanbul Technical University Autonomous Systems Research Laboratory Department of Mechanical Engineering İstanbul Turkey

ISBN: (纸本)9781665433891

Within the last decade, e-commerce has increased at an extraordinary level. The widespread use of Unmanned Aerial Vehicles (VAVs) in the logistics sector can reduce traffic density, improve delivery time, and can provide contactless delivery. This work proposes a new hybrid VAV, that combines the benefits of vertical take-off and land vehicle and a fixed-wing aircraft. It can carry multiple packages, which can decent automatically towards the recipients. This approach eliminates time-consuming landing maneuvers of the VA V for delivery. This work focuses on the design of the vehicle, and the challenges of the transitions from VTOL to aircraft modes and vice versa with a Model Predictive controller. © 2021 IEEE.

关键词： Fixed wings

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Multi-mode Composite Track Estimation Method Based on Distributed Measurement Fusion 4

Multi-mode Composite Track Estimation Method Based on Distri...

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4th IEEE Advanced Information Management, Communicates, Electronic and Automation control Conference, IMCEC 2021

作者： Ke-Qiang, Xia Meng, Xing Chun-Yan, Du Na, Fu Jian-Ping, Chen Gan-Hua, Li Ji-Yuan, Lv State Key Laboratory of Astronautic Dynamics Hunan University of Technology Zhuzhou China China xi'An Satellite Control Center Xi'an China Manned Space System Research Center Beijing China

ISBN: (纸本)9781728185347

In the multi-mode track fusion algorithm, the commonly used method based on state fusion is relatively small in calculation, but it is not the optimal estimation. The centralized filter fusion method based on measurement is the optimal, but the measurement equation has high dimension, and the calculation is large. In this paper, the extended measurement method is used to unify the dimensionality of distributed measurement data, and a distributed measurement fusion algorithm adapted to track estimation is designed, which can effectively reduce the computation cost, improve the reliability and fault-tolerant ability, and achieve the optimal estimation of state data. The simulation results of active and passive radar composite guidance show that the algorithm is simple in calculation and fast in convergence, and can guarantee the high precision optimal estimation of target trajectory. © 2021 IEEE.

关键词： Data fusion

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Multi-objective Group Decision and Cooperative Planning Based on Preference and Fuzzy Measure 1

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7th Chinese Conference on Swarm Intelligence and Cooperative control, CCSICC 2023

作者： Ma, Xiwen Xie, Wei Yang, Jingsong Zhang, Weidong Lu, Jinhui School of Oceanography Shanghai Jiao Tong University Shanghai China State Key Laboratory of Satellite Ocean Environment Dynamics Second Institute of Oceanography Ministry of Natural Resources Hangzhou China Department of Automation Shanghai Jiao Tong University Shanghai China Zhuhai China School of Information and Communication Engineering Hainan University Hainan Haikou China National Engineering Research Center of Ship and Shipping Control System Shanghai China Crossocean of Suzhou technology No. 218 East Oingdao Road Suzhou China

ISBN: (数字)9789819733323

ISBN: (纸本)9789819733316

To pursue interest balance and improve collaboration efficiency, this paper proposes a multi-agent cooperation method integrating decision-making and planning. Based on preference and fuzzy measures, this method can balance individual and group benefits under fuzzy uncertain environment. The equilibrium solution of a multi-agent multi-objective game, namely group decision-making (GDM) solution, can be obtained by the Gaussian oscillation particle swarm optimization (GOPSO) algorithm, which overcomes the dilemma of a multi-objective group game and improves the computational efficiency. Considering the smoothness and continuity of the trajectory, a heuristic motion planning (MP) generation model that satisfies the kinematic constraints and minimizes differential thrust is proposed, which improves the cooperation efficiency. To verify the performance of this proposed method, simulation results are presented and some comparative statements are given. © The Author(s), under exclusive license to Springer Nature Singapore Pte Ltd. 2024.

关键词： Decision making

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全球变暖导致易诱发臭氧污染的强地面太阳辐射频率增加

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Science Bulletin 2023年第4期68卷 388-392,M0003页

作者：寇文彬高阳张绍晴蔡文炬耿冠楠 Steven J.Davis 王宏郭修文程文轩曾欣然马铭晨王厚文王俏巧姚小红高会旺吴立新 Frontiers Science Center for Deep Ocean Multispheres and Earth System and Key Laboratory of Marine Environmental Science and EcologyMinistry of EducationOcean University of ChinaQingdao 266100China Laboratory for Ocean Dynamics and Climate Laoshan LaboratoryQingdao 266237China Key Laboratory of Physical Oceanography Institute for Advanced Ocean StudyFrontiers Science Center for Deep Ocean Multispheres and Earth SystemCollege of Oceanic and Atmospheric SciencesOcean University of ChinaQingdao 266100China Key Laboratory of Physical Oceanography–Institute for Advanced Ocean Studies Ocean University of ChinaLaoshan LaboratoryQingdao 266100China Commonwealth Scientific and Industrial Research Organisation Marine and Atmospheric Research Aspendale Victoria 3195Australia State Key Joint Laboratory of Environment Simulation and Pollution Control School of EnvironmentTsinghua UniversityBeijing 100084China Department of Earth System Science University of CaliforniaIrvine CA 92697USA College of Oceanic and Atmospheric Sciences Ocean University of ChinaQingdao 266100China Institute for Environmental and Climate Research Jinan UniversityGuangzhou 510000China

世界卫生组织2021年提出了新的臭氧标准,不仅加严了原有的短期暴露标准,还增加了暖季峰值的长期暴露指标.2019年秋季我国发生了大范围臭氧污染事件,特别是珠三角地区臭氧浓度异常增加最为突出,导致其暖季峰值超标,并且2019年长时间臭氧... 详细信息

世界卫生组织2021年提出了新的臭氧标准,不仅加严了原有的短期暴露标准,还增加了暖季峰值的长期暴露指标.2019年秋季我国发生了大范围臭氧污染事件,特别是珠三角地区臭氧浓度异常增加最为突出,导致其暖季峰值超标,并且2019年长时间臭氧污染事件增幅更大.本文发现地面太阳辐射与臭氧年际变化相关性远高于其他气象因子,即使在温度较低时,较强的太阳辐射依然可促进高臭氧浓度累积.数值模式显示强太阳辐射驱动天然源大幅增加,不仅促进臭氧浓度升高,更重要的是,对于长时间臭氧污染事件频率增加大于短期污染事件,从而大大促进臭氧超标天数的增加.结合高分辨率地球系统模式和多模式比较计划,一致揭示在全球变暖下中国东部、美国东南部、欧洲各国,未来地面太阳辐射显著增加.通过将秋季地面太阳辐射日异常标准化,构建了臭氧气象指数,可有效揭示高臭氧浓度,阐明在北半球多个易发生臭氧污染区域,高臭氧气象指数天气发生频率显著增加,即利于高臭氧污染发生的气象条件在全球变暖下可能会更加频繁地发生.

关键词：臭氧浓度全球变暖天然源美国东南部气象指数臭氧污染气象条件短期暴露

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