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arXiv 2021年

作者： Jones, Morgan Peet, Matthew M. The Department of Automatic Control and Systems Engineering The University of Sheffield Amy Johnson Building Mappin Street SheffieldS1 3JD United Kingdom The School for the Engineering of Matter Transport and Energy Arizona State University TempeAZ85298 United States

Many dynamical systems described by nonlinear ODEs are unstable. Their associated solutions do not converge towards an equilibrium point, but rather converge towards some invariant subset of the state space called an attractor set. For a given ODE, in general, the existence, shape and structure of the attractor sets of the ODE are unknown. Fortunately, the sublevel sets of Lyapunov functions can provide bounds on the attractor sets of ODEs. In this paper we propose a new Lyapunov characterization of attractor sets that is well suited to the problem of finding the minimal attractor set. We show our Lyapunov characterization is non-conservative even when restricted to Sum-of-Squares (SOS) Lyapunov functions. Given these results, we propose a SOS programming problem based on determinant maximization that yields an SOS Lyapunov function whose 1-sublevel set has minimal volume, is an attractor set itself, and provides an optimal outer approximation of the minimal attractor set of the ODE. Several numerical examples are presented including the Lorenz attractor and Van-der-Pol oscillator. Copyright © 2021, The Authors. All rights reserved.

关键词： Lyapunov functions

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automatic Detection of Nuclear Spins at Arbitrary Magnetic Fields via Signal-to-Image AI Model

arXiv

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arXiv 2023年

作者： Varona-Uriarte, B. Munuera-Javaloy, C. Terradillos, E. Ban, Y. Alvarez-Gila, A. Garrote, E. Casanova, J. Department of Physical Chemistry University of the Basque Country UPV/EHU Apartado 644 Bilbao48080 Spain EHU Quantum Center University of the Basque Country UPV/EHU Leioa Spain Bizkaia Science and Technology Park Astondo Bidea Edificio 700 Derio48160 Spain Departamento de Física Universidad Carlos III de Madrid Avda. de la Universidad 30 Leganés28911 Spain Department of Automatic Control and Systems Engineering University of the Basque Country UPV/EHU Bilbao48013 Spain

Quantum sensors leverage matter’s quantum properties to enable measurements with unprecedented spatial and spectral resolution. Among these sensors, those utilizing nitrogen-vacancy (NV) centers in diamond offer the distinct advantage of operating at room temperature. Nevertheless, signals received from NV centers are often complex, making interpretation challenging. This is especially relevant in low magnetic field scenarios, where standard approximations for modeling the system fail. Additionally, NV signals feature a prominent noise component. In this Letter, we present a signal-to-image deep learning model capable of automatically inferring the number of nuclear spins surrounding a NV sensor and the hyperfine couplings between the sensor and the nuclear spins. Our model is trained to operate effectively across various magnetic field scenarios, requires no prior knowledge of the involved nuclei, and is designed to handle noisy signals, leading to fast characterization of nuclear environments in real experimental conditions. With detailed numerical simulations, we test the performance of our model in scenarios involving varying numbers of nuclei, achieving an average error of less than 2 kHz in the estimated hyperfine constants. © 2023, CC BY.

关键词： Magnetic fields

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Combining Trajectory Data with Analytical Lyapunov Functions for Improved Region of Attraction Estimation

arXiv

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arXiv 2021年

作者： Lugnani, Lucas Jones, Morgan Alberto, Luís F.C. Peet, Matthew Dotta, Daniel Faculty of Electrical and Computer Engineering University of Campinas Brazil The Department of Automatic Control and Systems Engineering University of Sheffield United Kingdom The São Carlos Engineering School University of São Paulo São Carlos Brazil The School for the Engineering of Matter Transport and Energy Arizona State University Tempe United States

The increasing uptake of inverter based resources (IBRs) has resulted in many new challenges for power system operators around the world. The high level of complexity of IBR generators makes accurate classical model-based stability analysis a difficult task. This paper proposes a novel methodology for solving the problem of estimating the Region of Attraction (ROA) of a nonlinear system by combining classical model based methods with modern data driven methods. Our method yields certifiable inner approximations of the ROA, typical to that of model based methods, but also harnesses trajectory data to yield an improved accurate ROA estimation. The method is carried out by using analytical Lyapunov functions, such as energy functions, in combination with data that is used to fit a converse Lyapunov function. Our methodology is independent of the function fitting method used. In this work, for implementation purposes, we use Bernstein polynomials to function fit. Several numerical examples of ROA estimation are provided, including the Single Machine Infinite Bus (SMIB) system, a three machine system and the Van-der-Pol system. Copyright © 2021, The Authors. All rights reserved.

关键词： Lyapunov functions

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A Hybrid Adaptive Filter for Head Tracking in Augmented Reality (AR)-based Flight Simulators

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IEEE Transactions on Computers 2025年

作者： Nwobodo, Onyeka J. Kuaban, Godlove Suila Nkemeni, Valery Wereszczynski, Kamil Cyran, Krzysztof A. Silesian University of Technology Department of Computer Graphics Vision and Digital Systems Faculty of Automatic Control Electronics and Computer Science Gliwice Poland Polish Academy of Sciences Institute of Theoretical and Applied Informatics Poland University of Buea Laboratory of Electrical Engineering and Computing Faculty of Engineering and Technology Buea Cameroon

This paper presents a novel approach for head tracking in augmented reality (AR) flight simulators using an adaptive fusion of Kalman and particle filters. This fusion dynamically balances the strengths of both algorithms, leveraging Kalman filters for computational efficiency and particle filters for handling non-linearities based on real-time factors such as sensor noise and head movement patterns. Our method demonstrates superior tracking precision and reduced latency, making it particularly effective for immersive pilot training in AR-based flight simulations. While focused on flight simulation, our approach holds high potential for broader applications in other AR and virtual reality (VR) environments where precise, real-time head tracking is crucial. These results provide actionable design guidance for developers optimizing tracking systems in environments that require fast response times and high accuracy. Future extensions of this research could explore the generalization of our approach across diverse AR applications, including human-computer interaction (HCI), medical simulations, and gaming. © 1968-2012 IEEE.

关键词： Flight simulators

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Switched PI control Based MRAS for Sensorless control of PMSM Drives Using Fuzzy-Logic-controller

Research Square

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Research Square 2021年

作者： Liu, Zhao-Hua Nie, Jie Wei, Hua-Liang Wu, Fa-Ming Chen, Lei Zhang, Zhu School of Information and Electrical Engineering Hunan University of Science and Technology Xiangtan411201 China Department of Automatic Control and Systems Engineering University of Sheffield SheffieldS1 3JD United Kingdom CRRC Zhuzhou Institute Company Ltd Zhuzhou412007 China

With the use of sensorless control mechanical position sensors can be removed from the gearbox, so as to decrease the maintenance costs and enhance the system robustness. In this paper, switched PI control based model reference adaptive system (MRAS) observer using Fuzzy-Logic-controller (FLC) is introduced for sensorless control of permanent magnet synchronous motor (PMSM) drives. The main work and innovation of this paper include: 1) An FLC is designed for speed and current control. The response performance of speed regulation and the accuracy of the command voltage are improved and the difficulty of manual adjustment of control parameters is avoided. In addition, the disturbance observer is established to compensate the nonlinear effect caused by voltage source inverter (VSI). Therefore, the robustness of PMSM vector control system is improved and the sensorless control precision is guaranteed. 2) A sensorless control strategy of a switched PI control based MRAS observer is proposed for stator resistance tracking, which can improve the accuracy of resistance estimation and improve the dynamic performance of sensorless control. 3) The experimental results are given to verify the availability of the proposed scheme. © 2021, CC BY.

关键词： Sensorless control

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Possibility of Using Technologies of Augmented and Virtual Reality for Acquisition Hard and Soft Skills of Electrical engineering Specialists

Possibility of Using Technologies of Augmented and Virtual R...

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International Conference on Modern Electrical and Energy systems (MEES)

作者： Olha Chencheva Volodymyr Chenchevoi Andriy Perekrest Yurii Morozov Oksana Zbyrannyk Mykhaylo Lytvynenko Department of Civil and Labour Safety Geodesy and Land Management Kremenchuk Mykhailo Ostrohradskyi National University Kremenchuk Ukraine Systems of Automatic Control and Electric Drive department Kremenchuk Mykhailo Ostrohradskyi National University Kremenchuk Ukraine Department of computer engineering and electronics Kremenchuk Mykhailo Ostrohradskyi National University Kremenchuk Ukraine “MOBIMODS” Sp. z o.o. Kremenchuk Ukraine Department of Economics and Management Kremenchuk Mykhailo Ostrohradskyi National University Kremenchuk Ukraine

ISBN: (纸本)9798350346848

The paper explores the possibilities of using augmented and virtual reality technologies to create distance online courses in order to ensure the acquisition of hard and soft skills of electrical engineering specialists. The use of 3D visualization, animation, sound accompaniment, subtitling in the development and formation of training courses of educational components allows you to fill it with the necessary informational content, immersing the student in a real production environment. The use of augmented reality allows you to adapt the educational process and provide the necessary competencies for the real technological process and equipment.

关键词： Training Electrical engineering Visualization Computer aided instruction Solid modeling Three-dimensional displays Psychology

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Optimal time-domain moment matching with partial placement of poles and zeros

Optimal time-domain moment matching with partial placement o...

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European control Conference (ECC)

作者： T. C. Ionescu O. V. Iftime I. Necoara Dept. of Automatic Control & Systems Eng. Politehnica Univ. of Bucharest Bucharest Romania Department of Economics Econometrics and Finance Faculty of Economics and Business University of Groningen Groningen The Netherlands Department of Automatic Control and Systems Engineering University Politehnica Bucharest Bucharest Romania

ISBN: (数字)9783907144022

ISBN: (纸本)9781728188133

In this paper we consider a minimal, linear, time-invariant (LTI) system of order n, large. Our goal is to compute an approximation of order ν 2 norm of the approximation error. For this, in the family of ν order parametrized models that match ν moments we impose ℓ+k linear constraints yielding a subfamily of models with ℓ poles and k zeros imposed. Then, in the subfamily of ν order models matching ν moments, with ℓ poles and k zeros imposed we propose an optimization problem that provides the model yielding the minimal H 2 -norm of the approximation error. We analyze the first-order optimality conditions of this optimization problem and compute explicitly the gradient of the objective function in terms of the controllability and the observability Gramians of the error system. We then propose a gradient method that finds the (optimal) stable model, with fixed ℓ poles and k zeros.

关键词： Mathematical model Computational modeling Poles and zeros Linear systems Biological system modeling

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A modified dynamic time warping (MDTW) approach and innovative average non-self Match distance (ANSD) method for anomaly detection in ECG recordings

arXiv

引用

arXiv 2021年

作者： Yao, Xinxin Wei, Hua-Liang Department of Automatic Control and Systems Engineering University of Sheffield SheffieldS1 3JD United Kingdom INSIGNEO Institute for in Silico Medicine University of Sheffield SheffieldS1 3JD United Kingdom

ECGs objectively reflects the working conditions of the hearts as these signals contain vast physiological and pathological information. In this work, in order to improve the efficiency and accuracy of "best so far" time series analysis-based ECG anomaly detection methods, a novel method, comprising a modified dynamic time warping (MDTW) and an innovative average non-self match distance (ANSD) measure, is proposed for ECG anomaly detection. To evaluate the performance of the proposed method, the proposed method is applied to real ECG data selected from the MIT-BIH heartbeat database. To provide a reference for comparison, two existing anomaly detection methods, namely, brute force discord discovery (BFDD) and adaptive window discord discovery (AWDD), are also applied to the same data. The experimental results show that our proposed method outperforms BFDD and AWD. © 2021, CC BY-NC-ND.

关键词： Electrocardiography

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Advanced method of movement compensation in video coding technologies 2

Advanced method of movement compensation in video coding tec...

引用

2nd IEEE International Conference on Advanced Trends in Information Theory, ATIT 2020

作者： Himenko, Victoriya Stetsenko, Oksana Fustii, Vadym Shaigas, Olexandr Eliseev, Evgeniy Kolomiitsev, Oleksii Kharkov National University of Radio Electronics Information and Network Engineering Department Kharkiv Ukraine Khatkiv National Air Force University Combat Use of Automatic Control Systems Department Kharkiv Ukraine Department of Ivan Kozhedub Kharkiv National University of Air Force Kharkiv Ukraine Department of National Technical University Kharkiv Polytechnic Institute Ukraine

Conceptual bases of construction of a method of compensation of movement of dynamic objects in a video stream directed on increase of efficiency of functioning of information and communication networks are considered.... 详细信息

ISBN: (纸本)9781728197999

关键词： Video signal processing

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A Data Driven Condition Monitoring of Chain Type Structures by Using Nonlinear Frequency Analyses 2

A Data Driven Condition Monitoring of Chain Type Structures ...

引用

2nd International Conference on Industrial Artificial Intelligence, IAI 2020

作者： Gao, Yi Luo, Zhong Zhu, Yunpeng Qiu, Yue Li, Yuqi Key Laboratory of Vibration and Control of Aero-Propulsion Systems Ministry of Education of China Northeastern University Shenyang110819 China State Key Laboratory of Structural Analysis for Industrial Equipment Dalian University of Technology Dalian116024 China University of Sheffield Department of Automatic Control and System Engineering SheffieldS13JD United Kingdom

ISBN: (纸本)9781728182162

A novel data driven condition monitoring approach is proposed in this study to detect the location of nonlinear faults in chain type structures. In this approach, the chain type system is characterized by representing the relationships between any two adjacent measurement points by NARX (Nonlinear Auto-Regressive with Exogenous Inputs) model. A new indicator for condition monitoring, known as the NET (Nonlinear Energy Transmission) indicator, is introduced based on the evaluation of the NRSFs (Nonlinear Response Spectrum Functions) of the chain type system. A 3 DOF system is employed to demonstrate the application of the data driven condition monitoring by using the NET indicator. A case study on the condition monitoring of a rotor-bearing system is then discussed to validate the advantage of the proposed approach in engineering practice. © 2020 IEEE.

关键词： Condition monitoring

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