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Annual Conference of Industrial Electronics Society

作者： Ze Li Xingyu Zheng Jinhui Xia Liling Wang Yuanbo Guo Xiaonan Gao Zhiheng Liu Xiaohua Zhang College of Electronic and Information Engineering Hebei University Baoding China School of Automation Southeast University Nanjing China Key Laboratory of Measurement and Control of Complex Systems of Engineering (Southeast University) Ministry of Education Southeast University Nanjing China School of Electrical Engineering Dalian University of Technology Dalian China School of Electrical Engineering and Computer Science KTH Royal Institute of Technology Stockholm Sweden The School of Electrical Engineering Dalian University of Technology Dalian China

Dual three-phase permanent magnet synchronous machine (DTP-PMSM) has attracted great attention due to its high reliability and high-power output capacities. However, the conventional single-voltage-vector-based predictive current control (SV-PCC) for DTP-PMSM presents high torque ripple and current harmonics, and high computational burden. To solve those issues, a modulated-virtual-vector-based PCC (MVV-PCC) for DTP-PMSM is proposed in this paper. Wherein, twenty-four VVs are synthesized by the inherent voltage vectors, and two VVs and one zero voltage vector with optimal duty cycles are determined and applied in each sampling period to improve the steady-state performance. The selection of optimal VVs and the calculation of the optimal duty cycles are simplified by integrating the deadbeat control and modulation scheme. Various comparisons are carried out to validate the effectiveness and superiority of the proposed MVV-PCC strategy.

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Nonlinear Cooperative Output Regulation with Input Delay Compensation

arXiv

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arXiv 2024年

作者： Zheng, Shiqi Ahn, Choon Ki Jiang, Xiaowei Yan, Huaicheng Shi, Peng The School of Automation China University of Geosciences Wuhan430079 China Hubei Key Laboratory of Advanced Control and Intelligent Automation for Complex Systems Wuhan430074 China The Engineering Research Center of Intelligent Technology for Geo-Exploration Ministry of Education Wuhan430074 China The Shaoyang Institute of Advanced Manufacturing Technology Shaoyang422000 China The School of Electrical Engineering Korea University Seoul136-701 Korea Republic of The Key Laboratory of Smart Manufacturing in Energy Chemical Process of Ministry of Education East China University of Science and Technology Shanghai200237 China The School of Electrical and Mechanical Engineering The University of Adelaide AdelaideSA5005 Australia

This paper investigates the cooperative output regulation (COR) of nonlinear multi-agent systems (MASs) with long input delay based on periodic event-triggered mechanism. Compared with other mechanisms, periodic event-triggered control can automatically guarantee a Zeno-free behavior and avoid the continuous monitoring of triggered conditions. First, a new periodic event-triggered distributed observer, which is based on the fully asynchronous communication data, is proposed to estimate the leader information. Second, a new distributed predictor feedback control method is proposed for the considered nonlinear MASs with input delay. By coordinate transformation, the MASs are mapped into new coupled ODE-PDE target systems with some disturbance-like terms. Then, we show that the COR problem is solvable. At last, to further save the communication resource, a periodic event-triggered mechanism is considered in the sensor-to-controller transmission in every agent. A new periodic event-triggered filter is proposed to deal with the periodic event-triggered feedback data. The MASs with input delay are mapped into coupled ODE-PDE target systems with sampled data information. Then, Lyapunov-Krasovskii functions are constructed to demonstrate the exponential stability of the MASs. simulations verify the validity of the proposed results. © 2024, CC BY-NC-ND.

关键词： Feedback control

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Periodic classical trajectories and quantum scars in many-spin systems

arXiv

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arXiv 2024年

作者： Ermakov, Igor Lychkovskiy, Oleg Fine, Boris V. Department of Mathematical Methods for Quantum Technologies Steklov Mathematical Institute of Russian Academy of Sciences 8 Gubkina St. Moscow119991 Russia Laboratory for the Physics of Complex Quantum Systems Moscow Institute of Physics and Technology Institutsky per. 9 Moscow region Dolgoprudny141700 Russia Skolkovo Institute of Science and Technology Bolshoy Bulvar 30 bld. 1 Moscow121205 Russia Institute for Theoretical Physics University of Leipzig Brüderstrasse 16 Leipzig04103 Germany

To probe the limits of dynamic thermalisation, we numerically investigate the stability of exceptional periodic classical trajectories in rather generic chaotic many-body systems and explore a possible connection between these trajectories and exceptional nonthermal quantum eigenstates known as "quantum many-body scars". The systems considered are chaotic spin chains with short-range interactions, both classical and quantum. On the classical side, the chosen periodic trajectories are such that all spins instantaneously point in the same direction, which evolves as a function of time. We find that the largest Lyapunov exponents characterising the stabillity of these trajectories have surprisingly strong and nontrivial dependencies on the interaction constants and chain lengths. In particular, we identify rather long spin chains, where the above periodic trajectories are Lyapunov-stable on many-body energy shells overwhelmingly dominated by chaotic motion. We show that the above phenomenology can be quantitatively described by connecting Lyapunov instabilities of translationally invariant periodic trajectories to irreducible representations of the translational symmetry group with well-defined wave vectors. We also find that instabilities around periodic trajectories in modestly large spin chains develop into a transient nearly quasiperiodic non-ergodic regime. In some cases, the lifetime of this regime is extremely long, which we interpret as a manifestation of Arnold diffusion in the vicinity of integrable dynamics. On the quantum side, we numerically investigate the dynamics of quantum states starting with all spins initially pointing in the same direction: these are the quantum counterparts of the initial conditions for the above periodic classical trajectories. Our investigation reveals the existence of quantum many-body scars for numerically accessible finite chains of spins 3/2 and higher. No evidence of quantum scars was observed for spin-1/2 chains, while spi

关键词： Lyapunov functions

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Mobile ion in a Fermi sea

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Physical Review A 2022年第2期105卷 023309-023309页

作者： Esben Rohan Christensen Arturo Camacho-Guardian Georg M. Bruun Center for Complex Quantum Systems Department of Physics and Astronomy Aarhus University Ny Munkegade 120 DK-8000 Aarhus C Denmark T.C.M. Group Cavendish Laboratory University of Cambridge JJ Thomson Avenue Cambridge CB3 0HE United Kingdom Shenzhen Institute for Quantum Science and Engineering and Department of Physics Southern University of Science and Technology Shenzhen 518055 China

The remarkable single-particle control of individual ions combined with the versatility of ultracold atomic gases makes hybrid ion-atom systems an exciting new platform for quantum simulation of few- and many-body quantum physics. Here, we study theoretically the properties of a mobile ion immersed in a quantum degenerate gas of fermionic atoms. Using an effective low-energy atom-ion interaction together with a well-established approach that includes exactly two-body correlations, we calculate the full spectral response of the ion and demonstrate the existence of several quasiparticle branches, which are charged analogs of the Fermi polaron observed in neutral atomic gases. Due to the long-range nature of the atom-ion interaction, these ionic Fermi polarons have several properties distinct from their neutral counterparts such as the simultaneous presence of several stable states and smooth transitions from repulsive to attractive polarons with increasing interaction strength. Surprisingly, the residue of the ionic polaron is shown to increase with the Fermi density for fixed interaction strength, which is in marked contrast with the neutral polaron. The properties of the ionic polaron approach that of the neutral polaron only in the low-density limit where the average interparticle spacing is larger than the characteristic length of the atom-ion interaction. We finally analyze the effects of the Fermi gas on the molecular ions, which are bound atom-dimer states.

关键词： Cold atoms & matter waves Fermi gases Polarons Scattering of atoms, molecules, clusters & ions Ions

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A Real-Time Multi-Task Framework for Guidewire Segmentation and Endpoint Localization in Endovascular Interventions

A Real-Time Multi-Task Framework for Guidewire Segmentation ...

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IEEE International Conference on Robotics and Automation (ICRA)

作者： Yan-Jie Zhou Shi-Qi Liu Xiao-Liang Xie Xiao-Hu Zhou Guan-An Wang Zeng-Guang Hou Rui-Qi Li Zhen-Liang Ni Chen-Chen Fan State Key Laboratory of Management and Control for Complex Systems Institute of Automation Chinese Academy of Sciences Beijing China School of Artificial Intelligence University of Chinese Academy of Sciences Beijing China CAS Center for Excellence in Brain Science and Intelligence Technology Beijing China CASIA-MUST Joint Laboratory of Intelligence Science and Technology Institute of Systems Engineering Macau University of Science and Technology China

Real-time guidewire segmentation and endpoint localization play a pivotal role in robot-assisted minimally invasive surgery, which is helpful to reduce radiation dose and procedure time. Nevertheless, the tasks often come with the challenge of limited computational resources. For this purpose, a real-time multi-task framework with two stages is developed. In the first stage, a Fast Attention-fused Network (FAD-Net) is proposed to obtain accurate guidewire segmentation masks. In the second stage, a lightweight localization network and a post-processing algorithm are designed to robustly predict the guidewire endpoint position. Quantitative and qualitative evaluations on intraoperative X-ray sequences from 30 patients demonstrate that the developed framework outperforms the previously-published results for the tasks, achieving state-of-the-art performance. Moreover, the inference rate of the developed framework is approximately 10.6 FPS, which meets the real-time requirement of X-ray fluoroscopy. These results indicate the proposed approach has the potential to be integrated into the robotic navigation framework for endovascular interventions, enabling robotic-assisted minimally invasive surgery.

关键词： Location awareness Minimally invasive surgery Navigation Prediction algorithms Real-time systems Robustness Inference algorithms

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The Effect of Ligand and Acid Promoter on Hydroesterification of Ethylene to Methyl Propionate and Kinetic Studies

SSRN

引用

SSRN 2022年

作者： Wang, Luming Li, Zengxi Wang, Erqiang Li, Chunshan School of Chemical Sciences University of Chinese Academy of Sciences Beijing100049 China Beijing Key Laboratory of Ionic Liquids Clean Process State Key Laboratory of Multiphase Complex Systems The National Key Laboratory of Clean and Efficient Coking Technology Institute of Process Engineering Chinese Academy of Sciences Beijing100190 China Huizhou Institute of Green Energy and Advanced Materials Advanced Energy Science and Technology Guangdong Laboratory Guangdong516081 China

A palladium/tris(4-fluorophenyl)phosphine/p -toluenesulfonic acid catalytic new system was developed for the synthesis of methyl propionate from ethylene hydroesterification. The influence mechanism of phosphine ligands and acid promoters on catalytic activity was systematically studied. A volcano relationship between the catalytic activity and the electric effect of phosphine ligand was achieved through the characterization of 31P NMR of selenium phosphine compounds. An acid strength range favourable to the hydroesterification of ethylene was found by characterizing the pKa value of Brønsted acid. Then, the effect of phosphine ligand/Pd(OAc)2 ratio, p-toluenesulfonic/Pd(OAc)2 ratio, temperature, time, and pressure on this reaction were investigated. Finally, the elementary reaction-based kinetic model was developed, which indicated the insertion of methanol into Pd-acyl species with activation barrier of 83.1 kJ/mol is the rate-determining step. © 2022, The Authors. All rights reserved.

关键词： Ethylene

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Quantum coherence of Fermionic Gaussian states

引用

Results in Physics 2025年 69卷

作者： Wang, Yangyang Qi, Xiaofei Hou, Jinchuan Xu, Bing Physics Postdoctoral Research Station at Hebei Normal University Shijiazhuang 050024 China School of Mathematical Sciences Hebei Normal University Shijiazhuang 050024 China School of Mathematics and Statistics Shanxi University Taiyuan 030006 China Key Laboratory of Complex Systems and Data Science of Ministry of Education Shanxi University Taiyuan Shanxi 030006 China College of Mathematics Taiyuan University of Technology Taiyuan 030024 China

In the present paper, quantum coherence of fermionic Gaussian states is investigated from the point of quantum resource theory. Some characterizations of m-mode (m≥1) incoherent fermionic Gaussian states and incoherent fermionic Gaussian channels are obtained, two quantification measures of fermionic Gaussian quantum coherence based on respectively the relative entropy and the Hellinger distance are proposed, and some formulas to calculate the value of these measures are established. It is shown that the m-mode fermionic Gaussian coherence is a quantum resource. © 2025 The Authors

关键词： Fermionic Gaussian channels Fermionic Gaussian states Quantum coherence

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Path Planning for Distribution Network Robots with Adaptive Simulated Annealing-Enhanced Artificial Potential Field Method

Path Planning for Distribution Network Robots with Adaptive ...

引用

IEEE International Conference on Industrial technology (ICIT)

作者： Baichao Zhang Xin Chen Jinge Chen Jinbin Li Xiaokai Wang Xu Jian School of Automation China University of Geosciences Wuhan China Hubei Key Laboratory of Advanced Control and Intelligent Automation for Complex Systems Wuhan China Engineering Research Center of Intelligent Technology for Geo-Exploration Ministry of Education Wuhan China State Grid Hubei Electric Power Co. Ltd. Electric Power Science Research Institute Wuhan P. R. China Hubei Fangyuan Dongli Electric Power Science Research Co. Ltd Wuhan P. R. China

ISBN: (数字)9798331521950

ISBN: (纸本)9798331521967

In this paper, we propose a hybrid algorithm that combines an improved Artificial Potential Field (APF) method with the Simulated Annealing (SA) algorithm for path planning of an electric power operation robot manipulator in complex distribution grid environments. To address the unreachable target issue inherent in traditional APF, we introduce a distance regulation factor to optimize the repulsive function. This modification allows the manipulator to smoothly approach the target point as it nears, while the repulsion from obstacles gradually decreases. Additionally, to overcome the limitations of the traditional SA algorithm, such as its tendency to get trapped in local minimum solutions and its inefficiency in complex environments, we propose an adaptive temperature rise strategy. This strategy increases the temperature, enhancing the probability of escaping local optimal solutions. When the APF algorithm becomes trapped in a local optimum, the improved SA algorithm is applied to escape the local minimum. Once the local optimum is avoided, the algorithm switches back to APF to continue the path planning process. simulation results demonstrate that the proposed improved APF-SA algorithm adapts effectively to various complex environments, achieving shorter planning times and higher success rates compared to traditional APF and SA algorithms. It successfully resolves the unreachable target and local minimum problems associated with APF. Finally, the feasibility of the proposed APF-SA fusion algorithm is validated through experiments conducted on an electric power operation robot experimental platform for distribution grid applications.

关键词： Electric potential Adaptation models Force Distribution networks Simulated annealing Manipulators Path planning Planning Collision avoidance Robots

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Exploring CQA user contributions and their influence on answer distribution 32

Exploring CQA user contributions and their influence on answ...

引用

32nd International Conference on Software Engineering and Knowledge Engineering, SEKE 2020

作者： Yang, Yi Mao, Xinjun Xu, Zixi Lu, Yao College of Computer National University of Defense Technology Changsha China College of Information Science and Engineering Hunan Womens' University Changsha China Key Laboratory of Complex Systems Software Engineering National University of Defense Technology Changsha China

ISBN: (纸本)1891706500

In community question answering (CQA) sites like Stack Overflow (SO), users provide contributions driven by community incentives and self-motivation, which gives rise to micro activities of individual user and macro emergence of community. According to our empirical research, the emergence of answer distribution in SO is of concern, about 90% questions have no more than two answers and almost 40% of questions have no accepted answer due to lack of alternative acceptable answers. In this paper, we explore CQA user contributions by considering both the external incentives of community and internal motivations of users, and study why CQA users contribute and how they influence the macro emergence of answer distribution. We present CQA community model based on normative multi-agent system approach, in which the users are modeled as agents and the community incentives as norms. The internal motivations are studied based on self-determination theory. The paper further analyzes how the internal and external factors together influence the activities of agents and ultimately the answer distribution of the whole community. We conduct experiments based on a simulation system and the SO dataset to validate the effectiveness of our proposed model. The results show that our model can reproduce the emergence that well matches up with the observation on real community. © 2020 Knowledge systems Institute Graduate School. All rights reserved.

关键词： Multi agent systems

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Influence of Asymmetric Pre-Whirl Stator Spacing on Unsteady Characteristics of Pump-Jet Propulsor

SSRN

引用

SSRN 2022年

作者： Li, Fuzheng Liu, Guanshan Huang, Qiao-Gao Sun, Guocang Pan, Guang Qin, Denghui Key Laboratory of Unmanned Underwater Vehicle School of Marine Science and Technology Northwestern Polytechnical University Xi’an710072 China CSSC Systems Engineerings Research Institute Beijing100000 China Wuhan Second Ship Design and Research Institute Wuhan430205 China State Key Laboratory of Turbulence and Complex Systems Department of Aeronautics and Astronautics College of Engineering Peking University Beijing100871 China

This work studies the effect of the asymmetric pre-whirl stator spacing on the hydrodynamic performance of a pump-jet propulsor (PJP). The PJP contains a 13-stator and 7-rotor. The stator count is altered in the upper and lower half, and the total count is held constant. Results show that the steady performance is independent of the stator non-uniformity at design conditions. While the unsteady fluctuation of the rotor force and flow field is deeply affected by this adjustment. The cause is that the different incident angles of each rotor resulted from various stator spacing. The larger the stator count on one side, the great the incident angle in the corresponding location. Eventually, the stator root vortices in the lower half, where stator count is relatively larger, are weakened, whereas the tip vortex shape and intensity are not affected by the stator non-uniformity. Most notably, the PJP with a slight change of stator arrangement, in which the difference between two half parts is one, does not cause a significant change in flow, and the thrust amplitude at specific frequency decreases by 40% compared to the uniform stator case. © 2022, The Authors. All rights reserved.

关键词： Stators

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