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SSRN 2022年

作者： Jia, Jinzhang Wu, Yumo Zhao, Dan Li, Bin Wang, Dongming College of Safety Science and Engineering Liaoning Technical University Liaoning Fuxin123000 China Key Laboratory of Thermal Dynamic Disaster Prevention and Control of Ministry of Education Liaoning Technical University Liaoning Huludao125105 China Faculty of Civil Engineering and Architecture Zhanjiang University of Science and Technology Guangdong Zhanjiang524000 China School of Environmental and Chemical Engineering Shenyang Ligong University Shenyang110159 China

To explore the microscopic mechanism of gas adsorption by different functional groups in coal and provide theoretical support for the prevention and control of coal mine gas disasters, a slit-pore model and fragment model modified by different functional groups were built using Materials Studio software, based on density functional theory and the Monte Carlo method. The adsorption characteristics of seven different functional group models on the gas were analyzed, and the microscopic mechanism of adsorption performance of different functional groups on CH 4 /CO 2 /N 2 was revealed. The results showed that the order of the electrophilic ability of each functional group fragment followed benzene ring >‒OH>‒C=O>‒O‒CH 3 >‒COOH>‒CH 3 >‒CH 2 ‒CH 3 , and the order of nucleophilic ability was benzene ring >‒CH 2 ‒CH 3 >‒CH 3 >‒COOH>‒OH>‒C=O>‒O‒CH 3 . After adding different functional groups to the surface of the complete activated carbon, the electrophilic ability and nucleophilic ability decreased. The adsorption heat was not only affected by the adsorption amount but also by the non-uniformity of the adsorbent surface. The oxygen-containing functional groups were beneficial to the adsorption of CO 2 gas, and the aliphatic functional groups were committed to the adsorption of CH 4 and N 2 . © 2022, The Authors. All rights reserved.

关键词： Coal

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RETRACTED ARTICLE: Optimal design and experimental study of a layer metering sensor for high-speed penetration through multi-layer hard targets

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Soft Computing 2021年第2期28卷 423-423页

作者： Yu, Haoyuan Zou, Qipeng Sui, Li Zhang, Li Science and Technology on Electromechanical Dynamic Control Laboratory Beijing Institute of Technology Beijing China Northwest Industries Group Co. Ltd Xi’an China

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Short-Range Detection of Ferromagnetic Target Based on Tunneling Magnetoresistance Sensor

Short-Range Detection of Ferromagnetic Target Based on Tunne...

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IEEE International Conference on Unmanned Systems (ICUS)

作者： Qiang Fan Jiahao Deng Zuodong Duan Xiaowei Wei Sha Xu Science and Technology on Electromechanical Dynamic Control Laboratory School of Mechatronical Engineering Beijing institute of Technology Beijing China

ISBN: (纸本)9781728137933

In order to improve the accuracy of short-range ferromagnetic target location and distance-determination, the short-range detection technology of ferromagnetic target based on tunneling magnetoresistance (TMR) sensor is studied in this paper. Based on the analysis of the tunneling magneto-resistance effect principle and the understanding of the relevant magnetic field detecting components, a suitable signal conditioning and signal processing circuit is designed to constitute the TMR magnetic detector. Two kinds of ferromagnetic targets with regular shapes are measured at different distances and orientations, and the measured data are analyzed by curve fitting method. The results show that the output signal amplitude value of the detector is inversely proportional to the cubic power of the relative distance between the detector and the measured target when it is in the near field (no more than 5 meters in this paper). And the influence of the measured target material and detection orientation on the relationship between the two also shows a certain correlation. On the basis of the short-range static detection of general ferromagnetic targets, dynamic tests were carried out with the aim of household cars, the results indicate that the detection distance of dynamic vehicles can reach 7 meters.

关键词： Xenon

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Sliding Mode Observation and control for Overhead Cranes with Varying Rope Length

Sliding Mode Observation and Control for Overhead Cranes wit...

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Chinese Automation Congress (CAC)

作者： Xuwei Huan Dan Niu Qi Li Jun Yang Guoyao Liu Xisong Chen Xi Xiao Key Laboratory of Measurement and Control of CSE Ministry of Education Southeast University Nanjing China Loughborough University Loughborough UK Nanjing Sciyon Automation Group Co. Ltd Nanjing China Aviation Key Laboratory of Science and Technology on Aero Electromechanical System Integration Nanjing China

ISBN: (纸本)9781665426480

This paper proposes a state observer and controller based on the second-order sliding mode scheme for under-actuated overhead cranes with load hoisting and lowering. The designed state observer can effectively estimate the uncertainty and unmodeled dynamics of crane systems, and provide appropriate driving force compensations for the sliding mode controller designed by coupling the load swing angle. This guarantees an accurate load positioning and residual swing elimination. Based on the Lyapunov stability criterion, the asymptotic stability of the control system is proved. Several simulations are implemented to verify the effectiveness and robustness of the proposed controller for anti-sway and positioning controls.

关键词： Cranes Uncertainty Force dynamics Observers Robustness Stability analysis

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Analysis on Stability of Three-loop Autopilot with An Acceleration Feedback Augmentation Loop

Analysis on Stability of Three-loop Autopilot with An Accele...

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第40届中国控制会议

作者： Hui Wang Tao Li Daoguang Tang Junfang Fan Yifang Yuan Luyao Zang Wugang Wang Chunyan Xiao School of Aerospace Engineering Beijing Institute of Technology Beijing Key Laboratory of UAV Autonomous Control Beijing Institute of Technology School of Electrical and Control Engineering North University of China Beijing Key Laboratory of High-Dynamic Navigation Technology Beijing Information Science and Technology University China PLA 63961 Unit Beijing System Design Institute of Electro-Mechanic Engineering Northwest Industries Group CO. Ltd.

In order to construct a stable augmentation loop, a novel three-loop autopilot structure with an acceleration feedback is proposed. Based on LQR and analytical methods, the design process of the controller parameters is deduced. For a static unstable missile, the control characteristics of a three-loop autopilot with acceleration feedback are compared with classical three-loop and pseudo-angle-of-attack feedback three-loop autopilots. It is pointed out that the closed-loop gain of the three-loop autopilot with acceleration signal feedback is 1, which is not affected by the control parameters. The autopilot can control the static unstable missile, and the acceleration signal is easier to obtain than the pseudo-angle-of-attack.

关键词： Acceleration feedback Stable augmentation loop Autopilot Static unstable missile

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Parameter determination for the optical path of digital holography based on improved particle swarm optimization

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Optica Acta: International Journal of Optics 2023年第10期70卷

作者： Yuan Chen Yuhui Fan Shaonan Liang Ming Dong Hongwei Ma Xiang Wan a College of Sciences Xi’an University of Science and Technology Xi’an People’s Republic of Chinab Shaanxi Key Laboratory of Mine Electromechanical Equipment Intelligent Detection and Control Xi’an University of Science and Technology Xi’an People’s Republic of China c College of Mechanical Engineering Xi’an University of Science and Technology Xi’an People’s Republic of China b Shaanxi Key Laboratory of Mine Electromechanical Equipment Intelligent Detection and Control Xi’an University of Science and Technology Xi’an People’s Republic of Chinac College of Mechanical Engineering Xi’an University of Science and Technology Xi’an People’s Republic of China

In digital holography (DH), the key parameters in the optical path structure, such as diffraction distance, optical path difference and deflection angle, affect greatly the image quality of holographic reconstruction. Thus, it is crucial to determine the appropriate values of parameters. In this paper, the influence of these parameters on the quality of reconstructed images is deeply analysed through the DH principle and numerical simulation. A method to optimize automatically the parameters in the optical path is proposed based on an improved particle swarm optimization algorithm. An experimental setup for reflective off-axis DH is constructed, and coin and optical resolution plate are taken as test samples to perform the experimental research. Experimental results demonstrate that the proposed method can not only effectively enhance the quality of reconstructed images in the light of five indicators but also reduce the complexity and difficulty of adjusting the optical path parameters in the experiments.

关键词： Digital holography deflection angle diffraction distance optical path difference parameter optimization improved particle swarm optimization

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Evaluation method of UAV cluster simulation models with different granularity based on sensitivity analysis

Evaluation method of UAV cluster simulation models with diff...

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2019 IEEE International Conference on Unmanned Systems, ICUS 2019

作者： Zhang, Qing Li, Jing Shen, Chao Science and Technology on Omplex-System Control and Intelligent-Agent Cooperation Laboratory Beijing China Beijing Electromechanical-Engineering Institute Beijing China

ISBN: (纸本)9781728137926

Simulation test evaluation of the unmanned aerial vehicle (UAV) cluster operational effectiveness requires the support of simulation models with different granularity levels such as precise, medium, and coarse levels. In order to ensure the confidence of the evaluation, difficulties in evaluating the effectiveness of different granularity simulation models of the UAV cluster need to be solved. Aiming at the problem that the existing evaluation methods are not fully applicable due to the constraints of a large number of actual flight data, this paper proposes the evaluation method of different granularity simulation models, completes the rationality analysis of the granularity partitioning of UAV cluster at three levels: precise, medium and coarse, and the rationality analysis of the support relationship between different granularity models. Based on the special input method, capability meta-models of the UAV cluster with different granularity are evaluated. The evaluation method of different granularity simulation models of the UAV cluster based on sensitivity analysis is proposed. The sensitivity factor extraction and simulation analysis of precise granularity in the motion layer, medium granularity in the perception layer, and coarse granularity in the decision layer are completed. The validity evaluation of the different granularity simulation models has laid a solid foundation for the simulation test evaluation of the UAV cluster operational effectiveness. © 2019 IEEE.

关键词： Sensitivity analysis

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State Estimation for Linear Systems with Quadratic Outputs

arXiv

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arXiv 2023年

作者： Berkane, Soulaimane Theodosis, Dionysis Hamel, Tarek Dimarogonas, Dimos V. Département d’informatique et d’ingénierie Université du Québec en Outaouis GatineauQC Canada theDepartment of Electrical Engineering Lakehead University ON Canada the Dynamic Systems and Simulation Laboratory Technical University of Crete Greece the Divi-sion of Decision and Control Systems School of Electrical Engineering and Computer Science KTH Royal Institute of Technology Sweden I3S-CNRS University Côte d’Azur Institut universitaire de France France

This letter deals with the problem of state estimation for a class of systems involving linear dynamics with multiple quadratic output measurements. We propose a systematic approach to immerse the original system into a linear time-varying (LTV) system of a higher dimension. The methodology extends the original system by incorporating a minimum number of auxiliary states, ensuring that the resulting extended system exhibits both linear dynamics and linear output. Consequently, any Kalman-type observer can showcase global state estimation, provided the system is uniformly observable. © 2023, CC BY.

关键词： Time varying systems

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State Estimation for a Class of Linear Systems with Quadratic Output ⁎ ⁎

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IFAC-PapersOnLine 2021年第9期54卷 261-266页

作者： Dionysios Theodosis Soulaimane Berkane Dimos V. Dimarogonas Dynamic Systems and Simulation Laboratory School of Production Engineering and Management Technical University of Crete Greece Département d’informatique et d’ingénierie Université du Québec en Outaouis Gatineau Québec Canada Division of Decision and Control Systems School of Electrical Engineering and Computer Science KTH Royal Institute of Technology Sweden

This paper deals with the problem of state estimation for a class of linear time-invariant systems with quadratic output measurements. An immersion-type approach is presented that transforms the system into a state-affine system by adding a finite number of states to the original system. Under suitable persistence of excitation conditions on the input and its higher derivatives, global state estimation is exhibited by means of a Kalman-type observer. A numerical example is provided to illustrate the applicability of the proposed observer design for the problem of position and velocity estimation for a vehicle navigating in the n— dimensional Euclidean space using a single position range measurement.

关键词： Observers observability state estimation linear system quadratic output

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Self-powered wireless impedance sensing for structural health monitoring

Self-powered wireless impedance sensing for structural healt...

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IEEE International Conference on Unmanned Systems (ICUS)

作者： Yue Feng Xusong Tang Bohan Shao Yanhui Han Science and Technology on Electromechanical Dynamic Control Laboratory Beijing Institute of Technology Beijing China Beijing Orient Institute of Measurement & Test Beijing China

ISBN: (纸本)9781728137933

Structural damage is often accompanied by equipment failures and safety incidents. For example, aircraft accidents often result from wing breaks and landing gear damage. The self-powered wireless sensing technology is ideal tool for monitoring structural health in multi-locations. In this work, we designed an airflow-driven energy harvester (EH) and integrate into wireless impedance sensing system. Also, the Energy Management and control Circuit (EMC) is designed to provide a stable DC voltage for intermittently driven sensing system. The experimental results show that the self-powered impedance sensing system can operate at every 3 min at a wind speed of 8 m/s. The system error is within 5% compared to the Agilent 4294A (Precision Impedance Analyzer) and the characteristics of the material cracks could be successfully detected and analyzed.

关键词： Energy harvesting Monitoring

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