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Model Predictive Control for Steering system of Water-Jet Propulsion

Journal of Shanghai Jiaotong university(science) 2020年第3期25卷 299-303页

作者： GONG Zhenghua SONG Chenwei LI Gangqiang CHEN Jianping XU Zijing YUAN Jingqi MOE Key Laboratory of Marine Intelligent Equipment and System Shanghai Jiao Tong UniversityShanghai 200240China Laboratory of Science and Technology on Waterjet Propulsion Shanghai 200011China Marine Design&Research Institute of China Shanghai 200011China Department of Automation Shanghai Jiao Tong UniversityShanghai 200240China

Water-jet propulsion is a widely applied ship propulsion *** steering control system has an important impact on manoeuvre *** this paper,transfer function model is firstly established on the basis of mechanism analysis of water-jet steering ***,by considering the variability of model parameters and input constraints in practical operation,a model predictive controller is designed for steering system ***,model based disturbance observer is employed in an attempt to reject environmental *** performance of the proposed model predictive control (MPC) scheme for a particular steering system is compared with that of conventional proportional integral derivative (PID) control *** results demonstrate that the proposed model predictive controller outperforms conventional PID controller,particularly in robustness,response delay and tracking accuracy.

关键词： water-jet propulsion steering system model predictive control(MPC) disturbance observer

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Numerical simulation and experimental research of shear-driven water film on flat plate

Numerical simulation and experimental research of shear-driv...

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CSAA/IET International Conference on Aircraft Utility systems (AUS 2024)

作者： Qinyang Li Ning Guan Bo Ning Guangya Zhu Dalin Zhang Weijian Chen Key Laboratory of Aircraft Environment Control and Life Support MIIT Nanjing University of Aeronautics and Astronautics Nanjing People's Republic of China College of Aeronautics Shandong Jiaotong University No.5001 Haitang Road Changqing University Science and Technology Park Jinan People's Republic of China Utility System Design and Research Department Jiangxi Hongdu Aviation Industry Group Company Ltd. Nanchang People's Republic of China

ISBN: (数字)9781837242108

The supercooled water droplets in the air will form a water film on the aircraft during flight, which will then form icing, which will have an impact on the aerodynamic performance of the aircraft and even endanger the flight safety. In this paper, based on the Eulerian Wall Films model, the partial wetting effect is introduced, and the water film flow on flat plates driven by airflow shear force is investigated. The flow behaviours of water film with different contact angles under different flow rates were explored through water film test. The effectiveness of the calculation method for water film flow characteristics in this paper was verified by comparison between numerical simulation and test records, which laid a foundation for the anti-icing calculation in subsequent studies.

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Mechanical memory of excitable cells induced by mechanosensitive channel inactivation

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Biophysical Journal 2025年

作者： Jinjiang Xie Fangtao Mao Yuehua Yang Hongyuan Jiang CAS Key Laboratory of Mechanical Behavior and Design of Materials CAS Center for Excellence in Complex System Mechanics Department of Modern MechanicsUniversity of Science and Technology of China Hefei Anhui 230026 China

Recent experiments have unveiled a fascinating phenomenon: excitable cells exhibit mechanical memory, whereby their present excitation behaviours strongly depend on their past mechanical experiences. However, the underlying mechanism of this phenomenon remains elusive. Here, we introduce an electromechanical framework that integrates mechanical cell deformation, state transformations of mechanosensitive (MS) channels (such as Piezo channels), and transmembrane ion fluxes. We reveal that MS channel inactivation yields a history-dependent excitation dynamics, characterized by a progressive decline in subsequent activated currents with increasing amplitude, speed, and duration of prior mechanical stimuli. Moreover, MS channel inactivation in preceding stimulation results in a refractory period during which cells cannot elicit new action potentials upon subsequent mechanical stimuli. Finally, we show that cells can adapt to preceding mechanical stimulation due to inactivation of MS channels, resulting in a higher activated threshold stimulation. Thus, MS channel inactivation favors the reduction of firing activities in response to prolonged and repeated mechanical stimuli (“neural adaptation”), which may protect neurons against over-activation and damage. We then conduct two virtual experiments to predict how changes in mechanical properties of neurons modify their excitation behaviours. These findings together emphasize a critical role of MS channel inactivation in governing the mechanical memory and neural adaptation of excitable cells, shedding new light on the intricate interplay between mechanical forces and cellular electrical responses.

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Gaussian Decay Function-based Improved Moment Matching for Ocular Artifacts Removal

Gaussian Decay Function-based Improved Moment Matching for O...

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IEEE International Conference on Bioinformatics and Biomedicine (BIBM)

作者： Hua Jiang Qiuxia Shi Siying Liu Jiuying Zhang Qinglin Zhao Bin Hu Gansu Provincial Key Laboratory of Wearable Computing School of Information Science and Engineering Key Laboratory of Special Functional Materials and Structural Design Ministry of Education Lanzhou University Lanzhou China CAS Center for Excellence in Brain Science and Intelligence Technology Shanghai Institutes for Biological Sciences Chinese Academy of Sciences Chinese Academy of Sciences Joint Research Center for Cognitive Neurosensor Technology of Lanzhou University & Institute of Semiconductors Engineering Research Center of Open Source Software and Real-Time System (Lanzhou University) Ministry of Education Key Laboratory of Special Functional Materials and Structural Design (Lanzhou University) Ministry of Education Lanzhou China

ISBN: (数字)9781665468190

ISBN: (纸本)9781665468206

Electroencephalogram (EEG) equipped with high time resolution that distracted by incoherent brain sources which including ocular artifacts (OAs) generating by blinks is of great significance. Therefore, these OAs got corrected before extracting information from EEG is indispensable. Improved Moment Matching (IMM) is a high-speed denoising algorithm suitable for removing OA in multi-channel EEG, which is an improvement of the moment matching method used to remove stripe noise in hyperspectral images. On foundation of this, this paper proposes an optimization algorithm for IMM based on Gaussian decay function (IMM_G). In the first place, the construction of the reference signal is optimized via utilizing a Gaussian decay function, thereby preventing the signal distortion caused by the filter. And then, a method for judging the to-be-processed interval is proposed to realizes the individualized processing of different channels. As a result, through quantitative comparison experiments with simulated data and real data from the UAIS laboratory, it was identified that IMM_G showed less time complexity, significantly enhanced arithmetic speed and denoising consequence while the detail retention ability of the original method for the non-blinking region of multi-channel EEG data is maintained. Hence, this method could be extensively used in High-density EEG (hdEEG) OAs removal scene.

关键词： Electrooculography Noise reduction Filtering algorithms Distortion Electroencephalography Recording Time-domain analysis

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BREAKING THE DEGREES-OF-FREEDOM LIMIT OF HOLOGRAPHIC MIMO COMMUNICATIONS: A 3-D ANTENNA ARRAY TOPOLOGY

arXiv

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arXiv 2023年

作者： Yuan, Shuai S.A. Wu, Jie Xu, Hongjing Wang, Tengjiao Li, Da Chen, Xiaoming Huang, Chongwen Sun, Sheng Zheng, Shilie Zhang, Xianmin Li, Er-Ping Sha, Wei E.I. College of Information Science and Electronic Engineering Zhejiang University Hangzhou310027 China Anhui Province Key Laboratory of Simulation and Design for Electronic Information System Hefei Normal University Hefei230601 China Wireless Network Research Department Huawei Technologies Shanghai201206 China School of Information and Communications Engineering Xi’an Jiaotong University Xi’an710049 China School of Electronic Science and Engineering University of Electronic Science and Technology of China Chengdu611731 China

The performance of holographic multiple-input multiple-output (MIMO) communications, employing two-dimensional (2-D) planar antenna arrays, is typically compromised by finite degrees-of-freedom (DOF) stemming from limited array size. The DOF constraint becomes significant when the element spacing approaches approximately half a wavelength, thereby restricting the overall performance of MIMO systems. To break this inherent limitation, we propose a novel three-dimensional (3-D) antenna array that strategically explores the untapped vertical dimension. We investigate the performance of MIMO systems utilizing 3-D arrays across different multi-path scenarios, encompassing Rayleigh channels with varying angular spreads and the 3rd generation partnership project (3GPP) channels. We subsequently showcase the advantages of these 3-D arrays over their 2-D counterparts with the same aperture sizes. As a proof of concept, a practical dipole-based 3-D array, facilitated by an electromagnetic band-gap (EBG) reflecting surface, is conceived, constructed, and evaluated. The experimental results align closely with full-wave simulations, and channel simulations substantiate that the DOF and capacity constraints of traditional holographic MIMO systems can be surpassed by adopting such a 3-D array configuration. © 2023, CC BY-NC-ND.

关键词： Energy gap

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Influence of manufacturing errors of bearing components on rotational accuracy of cylindrical roller bearings

Research Square

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Research Square 2021年

作者： Yu, Yongjian Li, Jishun Xue, Yujun School of Mechatronics Engineering Henan University of Science and Technology Luoyang471003 China Henan Key Laboratory for Machinery Design and Transmission System Henan University of Science and Technology Luoyang471003 China Luoyang LYC Bearings Co. Ltd State Key Laboratory of Aviation Precision Bearings Luoyang471039 China

Understanding the influence of bearing component manufacturing errors and roller number on the rotational accuracy of rolling bearings is crucial in the design of high precision bearings. The rotational accuracy of an assembled bearing is dependent upon roller number and manufacturing error of the bearing components. We propose a model for calculating the rotational accuracy of a cylindrical roller bearing;we experimentally verified the effectiveness of the model in predicting the radial run-out of the inner ring proposed in the previous paper in this series. We sought to define the key contributing factors to the rotational accuracy by studying both the influence of the coupling effect of the roller number and the influence of the manufacturing errors in the inner raceway, outer raceway, and rollers on the motion error. The model and results will help engineers choose reasonable manufacturing tolerances for bearing components to achieve the required rotational accuracy. © 2021, CC BY.

关键词： Rollers (machine components)

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Detecting bulk carbon ferromagnetism in graphene multi-edge structure

arXiv

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arXiv 2023年

作者： Wang, Chao Jian, Nan Yin, Meijie Zhang, Xi Yang, Zhi Mo, Xiuhao Kikkawa, Takashi Daimon, Shunsuke Saitoh, Eiji Li, Qian Yan, Wensheng Hou, Dazhi Yang, Lei Diao, Dongfeng Institute of Nanosurface Science and Engineering Shenzhen University Shenzhen518060 China Electron Microscopy Center of Shenzhen University Shenzhen518060 China National Key Laboratory of Radio Frequency Heterogeneous Integration Shenzhen University Shenzhen518060 China Department of Applied Physics The University of Tokyo Tokyo113-8656 Japan Tokyo152-8550 Japan Institute for AI and Beyond The University of Tokyo Tokyo113-8656 Japan WPI Advanced Institute for Materials Research Tohoku University Sendai980-8577 Japan National Synchrotron Radiation Laboratory School of Nuclear Science and Technology University of Science and Technology of China Anhui Hefei230029 China Synergetic Innovation Center of Quantum Information and Quantum Physics University of Science and Technology of China Hefei230026 China Key Laboratory of Education Ministry for Modern Design and Rotor-Bearing System Xi’an Jiaotong University Xi’an710049 China

The emergence of bulk carbon ferromagnetism is long-expected over years. At nanoscale, carbon ferromagnetism was detected in graphene nanoribbon segments1–3, graphene triangulene dimers4,5, and other graphene-like molecules6–8 by analyzing their magnetic edge states via scanning tunneling microscopy(STM)9, and its origin can be explained by local redistribution of electron wave function3,5,8. Recently, there are experimental efforts on discovering orbital ferromagnetism in twisted bilayer graphene10,11, which is still limited in STM region. In larger scale, carbon ferromagnetism can be created by deliberately producing defects in graphite12–14, and detected by macroscopic technical magnetization. Meanwhile, it becomes crucial to determine that the detected magnetization is originated from carbon rather than from magnetic impurities. One solution to eliminate this uncertainty is X-ray magnetic circular dichroism (XMCD). A contrast of dichroism at π* absorption energy was observed in the scanning x-ray microscope image of proton-irradiated graphite15. Nonetheless, a reproducible, full section of XMCD spectrum across C-1s absorption energy has not appeared yet, which should be decisive for assuring the indisputable existence of bulk carbon ferromagnetism. Besides, the lack of direct observation on the atomic structure of the ferromagnetic carbon leaves the structural origin of its ferromagnetism still in mist. In this work, for detecting bulk carbon ferromagnetism, we managed to grow all-carbon film consisting of vertically aligned graphene multi-edge (VGME), which wove into a three-dimensional hyperfine-porous network. Magnetization (M-H) curves and XMCD spectra co-confirmed bulk carbon ferromagnetism of VGME at room temperature, with the average unit magnetic momentum of ~0.0006 μB/atom. The influence of magnetic impurities on magnetization was excluded by both absorption spectra and inductively coupled plasma mass spectrometry measurements. The spin transfer behavio

关键词： Ferromagnetism

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Generation of super-resolved optical needle and multifocal array using graphene oxide metalenses

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Opto-Electronic Advances 2021年第2期4卷 1-11页

作者： Hongtao Wang Chenglong Hao Han Lin Yongtian Wang Tian Lan Chengwei Qiu Baohua Jia Centre for Translational Atomaterials Faculty of ScienceEngineering and TechnologySwinburne University of TechnologyP.O.Box 218Hawthorn VIC 3122Australia Key Laboratory of Photoelectronic Imaging Technology and System Ministry of Education of ChinaSchool of Optics and PhotonicsBeijing Institute of TechnologyBeijing 100081China Department of Electrical and Computer Engineering National University of Singapore4 Engineering Drive 3Singapore 117583Singapore Engineering Product Development Pillar Singapore University of Technology and Design8 Somapah Road487372Singapore

Ultrathin flat metalenses have emerged as promising alternatives to conventional diffractive lenses,offering new possibilities for myriads of miniaturization and interfacial ***-based materials can achieve both phase and amplitude modulations simultaneously at a single position due to the modification of the complex refractive index and thickness by laser conversion from graphene oxide into graphene like *** this work,we develop graphene oxide metalenses to precisely control phase and amplitude modulations and to achieve a holistic and systematic lens design based on a graphene-based material *** experimentally validate our strategies via demonstrations of two graphene oxide metalenses:one with an ultra-long(~16λ)optical needle,and the other with axial multifocal spots,at the wavelength of 632.8 nm with a 200 nm thin *** proposed graphene oxide metalenses unfold unprecedented opportunities for accurately designing graphene-based ultrathin integratable devices for broad applications.

关键词： femtosecond laser reduction graphene oxide metalens multifocal spots optical needle

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Copula method of the kinematic accuracy of cylindrical roller bearing

Research Square

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Research Square 2021年

作者： Li, Lihong Xue, Yujun Li, Jishun Vehicles & Transportation Engineering Institute Henan University of Science and Technology Luoyang471003 China Henan Key Laboratory for Machinery Design and Transmission System Henan University of Science and Technology Luoyang471003 China State Key Laboratory of Aviation Precision Bearings Luoyang LYC Bearings Co. Ltd. Luoyang471039 China

The kinematic accuracy of cylindrical rollers bearing isn’t only influenced by the dimensional and form precision of its parts, but also more influenced by the cooperation among them. For cylindrical rollers bearing, the main indices of the kinematic accuracy are the ending beat and the radial run out of bearings. There must be dependent relationship between the cooperative action among the parts of bearings and the ending beat or the radial run out of bearings. This relationship is hardly expressed by mathematical formula. However, because the parts dimension deviation and the run out of bearings follow statistic law and have their distribution characteristics, while the copula joint distribution function can connect the run out of bearings with multiple parts dimension accuracy, the copula function is introduced to analyze the dependent relationship between bearing parts cooperative action and its kinematic accuracy. Based on the copula function of statistic theory, the kinematic accuracy of bearings can be forecast by parts geometric accuracy. © 2021, CC BY.

关键词： Kinematics

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Study on numerical model of vortex shedding for three-way pipe 48

Study on numerical model of vortex shedding for three-way pi...

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48th International Congress and Exhibition on Noise Control Engineering, INTER-NOISE 2019 MADRID

作者： Liu, Shuai Feng, ZhiPeng Wu, WanJun Jiang, XiaoZhou Huang, Xuan Qi, HuanHuan Science and Technology on Reactor System Design Technology Laboratory Nuclear Power Institute of China. No. 328 Changshun Avenue Shuangliu Chengdu China

ISBN: (纸本)9788487985317

The three-way pipe vortex shedding phenomenon is the main excitation source for pipe vibration, which can lead to the generation of acoustic resonance. The existing researches mainly focus on air and wet steam, however the researches on water medium is rare. In this paper, the formation mechanism of vortex shedding for three-way pipe under water medium is studied, and the influence of turbulence model, water compressibility, boundary layer and model size is discussed. A more accurate simulation model is established, The suggestions for the establishment of the three-way pipe vortex shedding simulation model are given according to the simulation results. © INTER-NOISE 2019 MADRID - 48th International Congress and Exhibition on Noise Control Engineering. All Rights Reserved.

关键词： Vortex shedding

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