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Adaptive control of track tension estimation using radial basis function neural network

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Defence Technology（防务技术） 2021年第4期17卷 1423-1433页

作者： ping-xin wang Xiao-ting Rui Hai-long Yu guo-ping wang Dong-yang Chen Institute of Launch Dynamics Nanjing University of Science and TechnologyNanjing210094China College of Electrical Energy and Power EngineeringYangzhou UniversityYangzhou225000China

Track tension is a major factor influencing the reliability of a *** order to reduce the risk of track peel-off,it is necessary to keep track tension ***,it is difficult to measure the dynamic tension during off-road *** on the analysis of the relation and external forces depending on free body diagrams of the idler,idler arm,road wheel and road arm,a theoretical estimation model of track tension is *** estimation results with multibody dynamics simulation results,the rationality of track tension monitor is *** the aid of this monitor,a track tension control system is designed,which includes a self-tuning proportional-integral-derivative(PID)controller based on radial basis function neural network,an electro-hydraulic servo system and an idler *** tightness of track can be adjusted by turning the idler *** results of the vehicle starting process indicate that the controller can reach different expected tensions quickly and *** with a traditional PID controller,the proposed controller has a stronger anti-disturbance ability by amending control parameters online.

关键词： Track tension Monitor Multibody dynamics Neural network Anti-disturbance ability

Framed slotted ALOHA with grouping tactic and binary selection for anti-collision in RFID systems

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The Journal of China Universities of Posts and Telecommunications 2009年第4期16卷 47-52页

作者： wang Ya-qi JIANG guo-ping wang Jing Center for Control and Intelligence Technology Nanjing University of Posts and Telecommunications Nanjing 210003 China

In radio frequency identification （RFID） systems, tag collision arbitration is a significant issue for fast tag identification. This article proposes a novel tag anti-collision algorithm called framed slotted ALOHA with grouping tactic and binary selection （GB-FSA）. The novelty of GB-FSA algorithm is that the reader uses binary tree algorithm to identify the tags according to the collided slot counters information. Furthermore, to save slots, tags are randomly divided into several groups based on the number of collided binary bits in the identification codes （IDs） of tags, and then only the number of the first group of tags is estimated. Performance analysis and simulation results show that the GB-FSA algorithm improves the identification efficiency by 9.9%-16.3% compared to other ALOHA-based tag anti-collision algorithms when the number of tags is 1000.

关键词： RFID anti-collision binary tree identification efficiency

A review on image-based rendering

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Virtual Reality & Intelligent Hardware 2019年第1期1卷 39-54页

作者： Yuan CHANG guo-ping wang School of Electronics Engineering and Computer Science Peking UniversityBeijing 100871China Beijing Engineering Research Center for Virtual Simulation and Visualization Beijing 100871China

Image-based rendering is important both in the field of computer graphics and computer vision,and it is also widely used in virtual reality *** more than two decades,people have done a lot of work on the research of image-based rendering,and these methods can be divided into two categories according to whether the geometric information of the scene is *** to this classification,we introduce some classical methods and representative methods proposed in recent *** also compare and analyze the basic principles,advantages and disadvantages of different ***,some suggestions are given for research directions on image-based rendering techniques in the future.

关键词： Image-based rendering Virtual reality Image interpolation Panorama

An efficient and modular modeling for launch dynamics of tubed rockets on a moving launcher

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Defence Technology（防务技术） 2021年第6期17卷 2011-2026页

作者： Qin-bo Zhou Xiao-ting Rui guo-ping wang Jian-shu Zhang Institute of Launch Dynamics Nanjing University of Science and TechnologyNanjingJiangsu Province210094PR China

This paper develops a modular modeling and efficient formulation of launch dynamics with marching fire(LDMF)using a mixed formulation of the transfer matrix method for multibody systems(MSTMM)and Newton-Euler *** a ground-borne multiple launch rocket systems(MLRS),the focus is on the launching subsystem comprising the rocket,flexible tube,and tube *** launching subsystem is treated as a coupled rigid-flexible multibody system,where the rocket and tube tail are treated as rigid bodies while the flexible tube as a beam with large ***,the tube and tube tail can be elegantly handled by the MSTMM,a computationally efficient order-N ***,the equation of motion of the in-bore rocket with relative kinematics *** tube using the Newton-Euler method is ***,the rocket,tube,and tube tail dynamics are coupled,yielding the equation of motion of the launching subsystem that can be regarded as a building block and further integrated with other *** deduced dynamics equation of the launching subsystem is not limited to ground-borne MLRS but also fits for tanks,self-propelled artilleries,and other air-borne and naval-borne weapons undergoing large *** simulation results of LDMF are given and partially verified by the experiment.

关键词： Launch dynamics Marching fire Transfer matrix method for multibody systems Multiple launch rocket system

Correction to“A Classification of Spectrum-determined Circulant Digraphs”

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Acta Mathematicae Applicatae Sinica 2021年第4期37卷 867-868页

作者： Zheng-xin QIN Xin-ping XU Ji-xiang MENG guo-ping wang School of mathematics and information technology Jiangsu Second Normal UniversityNanjing210013China College of Mathematics and System Sciences Xinjiang UniversityUrumqi830046China School of Mathematical Sciences Xinjiang Normal UniversityUrumqi830054China

We find an error in the proof of Lemma 4 in[3].This makes that Theorem 2 and Corollary 3 in[3]are also wrong,and the next counterexample shows this.

关键词： proof error Digraph

A novel launch dynamics measurement system for multiple launch rocket system and comparative analysis with numerical simulations

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Defence Technology（防务技术） 2021年第2期17卷 671-681页

作者： Li-lin Gu Xiao-ting Rui guo-ping wang Yi An Fu-feng Yang Min Wei Institute of Launch Dynamics Nanjing University of Science and TechnologyNanjing 210094PR China School of Physical and Mathematical Science Nanjing Tech UniversityNanjing 211816PR China

In this paper,a novel launch dynamics measurement system based on the photoelectric sensor pair is *** actual muzzle time(i.e.a time duration that originates from the initial movement to the rocket’s departure from the muzzle)and the muzzle velocity are *** with the classical methods,the actual muzzle time is obtained by eliminating the ignition *** comparative analysis method is proposed with numerical simulations established by the transfer matrix method for multibody *** experiment results indicate that the proposed measurement system can effectively measure the actual muzzle time and reduce the error of classical methods,which match well with the simulation results showing the launch dynamics model is reliable and helpful for further analysis and design of the MLRS.

关键词： Multiple launch rocket system Photoelectric sensor Launch dynamics measurement system Model verification Transfer matrix method for multibody systems

Some issues in diagnostics of solar chromospheric magnetic fields with the Mg b_2 line

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Research in Astronomy and Astrophysics 2014年第2期14卷 193-206页

作者： Xian-Yong Bai Yuan-Yong Deng Jiang-Tao Su guo-ping wang Key Laboratory of Solar Activity National Astronomical ObservatoriesChinese Academy of Sciences University of Chinese Academy of Sciences State Key Laboratory of Space Weather Chinese Academy of Sciences

Up to now, exact measurements of chromospheric magnetic fields have not been as successful as those done in the photosphere. We are currently engaging in diagnostics of chromospheric magnetic fields with the Mg b2 line by employing the Multi-Channel Solar Telescope at Huairou Solar Observing Station. Therefore, how to improve accuracy in the measurement is the main issue of our present study. To this end, we first study linear calibration coefficients for longitudinal and transverse components of chromospheric fields, which vary with wavelength, in the case of a weak field assumption. Then the polarization crosstalk introduced by instruments is analyzed in detail with two numerical simulation methods. Comparisons of the po- larization signals between cases with and without correction are presented. The result indicates that polarization accuracy is greatly improved after crosstalk correction.

关键词： Sun: chromospheric -- magnetic fields -- spectral profiles: radiative transfer

Five-channel frequency-division multiplexing using low-loss epsilon-near-zero metamaterial waveguide

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Science China(Physics,Mechanics & Astronomy) 2022年第7期65卷 129-137页

作者： Binbin Hong Lei Sun Wanlin wang Yanbing Qiu Naixing Feng Dong Su Nutapong Somjit Ian Robertson guo ping wang Institute of Microscale Optoelectronics Shenzhen UniversityShenzhen 518060China The Tenth Research Institute China Electronics Technology Group CorporationChengdu 610036China School of Electronic and Electrical Engineering University of LeedsLeeds LS29JTUK

The rapidly growing global data usage has demanded more efficient ways to utilize the scarce electromagnetic spectrum resource. Recent research has focused on the development of efficient multiplexing techniques in the millimeter-wave band(1-10 mm, or 30-300 GHz) due to the promise of large available bandwidth for future wireless networks. Frequency-division multiplexing is still one of the most commonly-used techniques to maximize the transmission capacity of a wireless *** on the frequency-selective tunnelling effect of the low-loss epsilon-near-zero metamaterial waveguide, we numerically and experimentally demonstrate five-channel frequency-division multiplexing and demultiplexing in the millimeter-wave *** show that this device architecture offers great flexibility to manipulate the filter Q-factors and the transmission spectra of different channels, by changing of the epsilon-near-zero metamaterial waveguide topology and by adding a standard waveguide between two epsilon-near-zero channels. This strategy of frequency-division multiplexing may pave a way for efficiently allocating the spectrum for future communication networks.

关键词： frequency-division multiplexing artificial effective medium epsilon-near-zero metamaterial integrated photonics

Suppression of vortex-induced vibrations of a flexible riser by adding helical strakes

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Journal of Hydrodynamics 2019年第3期31卷 622-631页

作者： Dong-yang Chen Laith K. Abbas guo-ping wang Xiao-ting Rui Wei-jie Lu School of Hydraulic Energy and Power Engineering Yangzhou University Yangzhou 225127 China Institute of La unch Dynamics Nanjing University of Science and Technology Nanjing 210094 China Nanjing Aerosun Corporation Nanjing 210000 China

3-D computational fluid dynamics/ computational structure dynamics (CFD/CSD) numerical two-way coupling simulations are conducted for a flexible rise in order to study the dynamic response performance of the riser with and without helical strakes exposed to the vortex-induced vibration (VIV). The VIV responses of a PVC riser without helical strakes are computed and compared with experimental data, to verify the accuracy of the present two-way coupling method. Subsequently, the dynamic behaviors of a short PVC riser with different kinds of helical strakes are studied. The vibration amplitudes along the riser, the trajectories of the riser's monitor point and the vortex shedding contours are obtained in a series of simulations. The helical strakes5 VIV suppression mechanisms are found involving the breaking of the vortex structures and the reduction of the vortex shedding frequency of the bare riser. Moreover, a good suppression effect can be achieved by attaching the helical strake structure with a reasonable geometrical configuration (such as the appropriate strake height, strake pitch, the number of starts and strake coverages) to the flexible riser. The effect is also diverse at different reduced velocity (Ur). The remarkable effect is found at Ur = l for the short riser, with about 97% reduction in the transverse vibration response.

关键词： Vortex-induced vibration (VIV) fluid structure interaction (FSI) Two-way coupling Helical strakes SST-SAS