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arXiv 2024年

作者： Liao, Jing-Xiao He, Chao Li, Jipu Sun, Jinwei Zhang, Shiping Zhang, Xiaoge Department of Industrial and Systems Engineering The Hong Kong Polytechnic University Hong Kong School of Instrumentation Science and Engineering Harbin Institute of Technology Harbin China School of Mechanical Electronic and Control Engineering Beijing Jiaotong University Beijing China

Blind deconvolution (BD) has been demonstrated as an efficacious approach for extracting bearing fault-specific features from vibration signals under strong background noise. Despite BD's desirable feature in adaptability and mathematical interpretability, a significant challenge persists: How to effectively integrate BD with fault-diagnosing classifiers? This issue arises because the traditional BD method is solely designed for feature extraction with its own optimizer and objective function. When BD is combined with downstream deep learning classifiers, the different learning objectives will be in conflict. To address this problem, this paper introduces classifier-guided BD (ClassBD) for joint learning of BD-based feature extraction and deep learning-based fault classification. Firstly, we present a time and frequency neural BD that employs neural networks to implement conventional BD, thereby facilitating the seamless integration of BD and the deep learning classifier for co-optimization of model parameters. Specifically, the neural BD incorporates two filters: i) a time domain quadratic filter to utilize quadratic convolutional networks for extracting periodic impulses;ii) a frequency domain linear filter composed of a fully-connected neural network to amplify discrete frequency components. Subsequently, we develop a unified framework to use a deep learning classifier to guide the learning of BD filters. In addition, we devise a physics-informed loss function composed of kurtosis, l2∕l4 norm, and a cross-entropy loss to jointly optimize the BD filters and deep learning classifier. Consequently, the fault labels provide useful information to direct BD to extract features that distinguish classes amidst strong noise. To the best of our knowledge, this is the first of its kind that BD is successfully applied to bearing fault diagnosis. Experimental results from three datasets demonstrate that ClassBD outperforms other state-of-the-art methods under noisy conditions

关键词： Feature extraction

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Privacy-Preservation for Distributed Quantized k-means Clustering

Privacy-Preservation for Distributed Quantized k-means Clust...

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Annual Allerton Conference on Communication, control, and Computing

作者： Apostolos I. Rikos Nicolas E. Manitara Gabriele Oliva Christoforos N. Hadjicostis Department of Electrical and Computer Engineering Division of Systems Engineering Boston University Boston MA USA Department of Electrical and Computer Engineering University of Cyprus Nicosia Cyprus Department of Engineering Unit of Automatic Control Università Campus Bio-Medico di Roma Rome Italy

In this paper, we enhance a distributed version of the well known k-means algorithm with privacy-preservation features. While ensuring that sensitive or confidential information remains undisclosed to unauthorized entities (in our case these entities are curious nodes within the network), we maintain the desirable features of the distributed algorithm: the transmitted values are quantized, which optimizes bandwidth utilization and alleviates communication bottlenecks, and nodes possess the ability to collectively determine when to terminate the algorithm, which enables the conservation of valuable resources. We introduce a novel privacy-preserving protocol that not only preserves the privacy of a node’s state, but it also ensures confidentiality about its cluster affiliation (i.e., it does not reveal to curious nodes whether a node participates in the update calculation for a specific centroid value). Moreover, we precisely characterize topological conditions that guarantee privacy preservation for individual nodes. Our distributed algorithm allows the formation of exclusive clusters within a finite time frame on any static and strongly connected directed graph.

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Biological Influence of Low-Frequency Electromagnetic Field Exposition Based on Selected Cell Death Markers

Biological Influence of Low-Frequency Electromagnetic Field ...

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ELEKTRO

作者： Robert Cichorowski Olga Kocikowska Marek Bajtoš Roman Radil Ladislav Janoušek Daria Gendosz De Carrillo Sebastian Student Faculty of Automatic Control Electronics and Computer Science Silesian University of Technology liwice Poland Department of Engineering and Systems Biology Faculty of Automatic Control Electronics and Computer Science Gliwice Poland Department of Physiology Faculty of Medical Sciences Silesian University of Medicine Katowice Poland Department of Electromagnetic and Biomedical Engineering Faculty of Electrical Engineering and Informational Technology Žilina Slovakia Department of Histology Faculty of Medical Sciences in Zabrze Silesian University of Medicine Zabrze Poland Biotechnology Center Silesian University of Technology Gliwice Poland

ISBN: (数字)9798350372359

ISBN: (纸本)9798350372366

This work presents the results of the examination of the HeLa cell line exposure on the ELF-EMF (extremely low-frequency electromagnetic field). In particular, the relationship between ELF-EMF exposition time and cell death. The examination of cell death hallmarks were examined by estimation levels of selected proteins - FACL4 (a protein that is a part of the ferroptosis pathway) and CK18 (Cytokeratin related to necrosis and apoptosis pathways) in the proposed model of workers exposed to ELF-EMF week.

关键词： Proteins Biological system modeling Estimation Electromagnetic fields

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A Persistent-Excitation-Free Method for System Disturbance Estimation Using Concurrent Learning

arXiv

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arXiv 2023年

作者： Zhang, Zengjie Liu, Fangzhou Liu, Tong Qiu, Jianbin Buss, Martin The Department of Electrical Engineering Eindhoven University of Technology Eindhoven5600 MB Netherlands The Research Institute of Intelligent Control and Systems Harbin Institute of Technology Harbin150001 China Automatic Control Engineering Technical University of Munich Munich80333 Germany

Observer-based methods are widely used to estimate the disturbances of different dynamic systems. However, a drawback of the conventional disturbance observers is that they all assume persistent excitation (PE) of the systems. As a result, they may lead to poor estimation precision when PE is not ensured, for instance, when the disturbance gain of the system is close to the singularity. In this paper, we propose a novel disturbance observer based on concurrent learning (CL) with time-variant history stacks, which ensures high estimation precision even in PE-free cases. The disturbance observer is designed in both continuous and discrete time. The estimation errors of the proposed method are proved to converge to a bounded set using the Lyapunov method. A history-sample-selection procedure is proposed to reduce the estimation error caused by the accumulation of old history samples. A simulation study on epidemic control shows that the proposed method produces higher estimation precision than the conventional disturbance observer when PE is not satisfied. This justifies the correctness of the proposed CL-based disturbance observer and verifies its applicability to solving practical problems. © 2023, CC BY-NC-SA.

关键词： Robust control

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Optimization Design and Dynamic Compensation Strategy of Inverter Parallel Virtual Impedance Based on Residual Generator

Optimization Design and Dynamic Compensation Strategy of Inv...

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IEEE Conference on Energy Internet and Energy System Integration (EI2)

作者： Changbin Hu Haiyang Huang Shanna Luo Huiru Wang Xuecheng Li Heng Lu North China University of Technology School of Electrical and Control Engineering Beijing China Beijing Kedong Electric Power Control System Co. Ltd Beijing China Department of Automatic Control and Complex Systems University of Duisburg-Essen Germany

To solve the power imbalance problem caused by the difference between the equivalent impedance of the inverter and the line impedance, and the power quality problem caused by the disturbance of load mutation, unbalanced load and nonlinear load, this paper proposes a closed-loop feedback dynamic compensation strategy based on the equivalent virtual impedance of the residual generator. Firstly, based on the parallel topology of inverters, a quasi-steady-state model is established on the dq axis. Based on the model, the power imbalance caused by the difference of output impedance and line impedance of different inverters and the power quality problems caused by load switching, unbalanced load, nonlinear load and other disturbances in parallel inverters are ***, a residual generator is established based on the inverter model. A virtual impedance equivalent controller Q vir (S) based on the residual generator is designed by the Luenberger observer principle. The disturbance information is fed back in real time through the feedback structure, and then the virtual impedance is adjusted to realize the power sharing of the inverter parallel system. Then, based on Euler parameterization and coprime factorization theory, a dynamic compensation architecture based on residual generator is designed. The transfer function of the dynamic compensation controller Q com (S) is obtained by model matching to realize the steady-state operation of parallel inverters and the improvement of system power quality. Finally, the effectiveness of the proposed architecture is verified on the experimental platform.

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On the existence and uniqueness of equilibria in meshed DC microgrids with CPLs

On the existence and uniqueness of equilibria in meshed DC m...

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Mediterranean Conference on control and Automation (MED)

作者： Andrei-Constantin Braitor George C. Konstantopoulos Department of Automatic Control and Systems Engineering The University of Sheffield Sheffield U.K Department of Electrical and Computer Engineering University of Patras Rion Greece

ISBN: (数字)9781665406734

ISBN: (纸本)9781665406741

In this paper, we analyse the existence and uniqueness of equilibria of constant power loads (CPLs) in meshed DC microgrid architectures. Given the CPLs’ nonlinear characteristic and negative impedance behaviour, they are commonly known to introduce a destabilising effect into the system, effect intuitively coined as negative impedance instability. In the present approach, we start by deriving the characteristic polynomial from the power balance equation aiming to observe the nature of the CPLs voltage solutions, and assess their feasibility. Then, the algebraic expression is transformed into a problem of existence and uniqueness of a fixed point, and further tested by means of contraction mapping theory. A sufficient condition for the sources’ voltage references is obtained to guarantee the existence and uniqueness of equilibria. This provides a useful guidance in selecting the voltage references in the control design process. A numerical investigation on a meshed DC microgrid is carried out to verify the acquired sufficient condition and its underlying developed theory.

关键词： Sufficient conditions control design systems operation Process control Microgrids High-voltage techniques Stability analysis

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Coordinating Active Distribution Networks with Multi-Microgrids: An ADMM-based Decentralized Adjustable Robust Operation Model

Coordinating Active Distribution Networks with Multi-Microgr...

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2022 International Conference on Power Energy systems and Applications, ICoPESA 2022

作者： Zhai, Junyi Ni, Chenyixuan Nimmegeers, Philippe Jiang, Yuning City Energy Research Institute Suzhou China University of Birmingham Department of Electronic Electrical and Systems Engineering Birmingham United Kingdom University of Antwerp Faculty of Applied Engineering Department Enm Faculty of Business and Economics Antwerp Belgium École Polytechnique Fédérale de Lausanne Automatic Control Laboratory Lausanne Switzerland

ISBN: (纸本)9781665410977

This paper proposes a decentralized adjustable robust operation model achieving the coordinated operation between an active distribution network (ADN) and microgrids (MGs). Thanks to the autonomous characteristic and heterogeneity of the individual agents in ADNs with multi-MGs, we develop a tailored alternating direction method of multipliers (ADMM)based fully decentralized framework. The linear decision rules are utilized to reformulate the microgrid two-stage adjustable robust operation problem as a computationally tractable solution such that the proposed adjustable robust extension of decentralized ADMM is capable of handling renewable energy uncertainties. The numerical results illustrate the effectiveness of the proposed model. © 2022 IEEE.

关键词： Optimization

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Modelling and control of a nonlinear distillation column: A, using fractional-order controllers 18

Modelling and Control of a nonlinear distillation column: A,...

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18th IEEE India Council International Conference, INDICON 2021

作者： Hanif, Omar Tiwari, Shipra Kumar, Vivek The University of Sheffield Department of Automatic Control and Systems Engineering Sheffield United Kingdom Motilal Nehru National Institute of Technology Department of Electrical Engineering Prayagraj India Indian Institue of Technology Roorkee Department of Electrical Engineering Roorkee India

ISBN: (纸本)9781665441759

This paper takes up the challenge of modelling a complex nonlinear distillation column type-A and designs four optimal controllers for the same. The nonlinear plant is first linearized into a linear higher-order model. Thereafter, it is reduced into a lower-order model. Subsequently, the controllers are designed for the lower-order linear model. The controllers are designed by reducing the error cost functions, namely Integral Square Error (ISE), Integral Absolute Error (IAE) and Integral Time Absolute Error (ITAE). The process of optimization is done heuristically using the Genetic Algorithm method of tuning. The four controllers designed are Proportional Integral Derivative, Fractional-order Proportional Integral Derivative, Tilt Integral Derivative and Fractional-order Internal Model control. A thorough comparison is made between the three designed controllers, first on the Single Input Single Output (SISO), then to the reduced-order linear model and finally to the main plant. The FO-IMC controller is shown as an exhibition controller designed using GA to demonstrate the novelty of its kind. It has also been compared, but the results show poor performances as it has not been tuned with the same parameters as the rest. © 2021 IEEE.

关键词： controllers

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On-The-Fly CNC interpolation using frequency-domain FFT-based filtering 55

On-The-Fly CNC interpolation using frequency-domain FFT-base...

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55th CIRP Conference on Manufacturing systems, CIRP CMS 2022

作者： Ward, Rob Sencer, Burak Panoutsos, George Ozturk, Erdem Department of Automatic Control and Systems Engineering University of Sheffield SheffieldS1 3JD United Kingdom Mechanical Engineering Department Oregon State University CorvallisOR United States Advanced Manufacturing Research Centre University of Sheffield RotherhamS60 5TZ United Kingdom

Finite Impulse Response filtering is increasingly becoming the interpolation method of choice in modern computer numerically controlled (CNC) machining centres. Recently, On-The-Fly (OTF) interpolation was introduced using direct convolution to adaptively change the FIR filter time constant throughout the toolpath. In this paper, it is shown that computational advantages can be gained by using frequency domain methods instead. This paper introduces a novel on-the-fly CNC interpolation method using Fast Fourier Transforms (FFTs). The presented OTF FFT method demonstrates up to 10 times increase in computational speed than the direct convolution OTF method. The effectiveness of the proposed method is validated in simulation based case studies. © 2022 The Authors. Published by Elsevier B.V.

关键词： CNC Interpolation FFT Convolution Motion control

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Continuous-Time Ultra-Wideband-Inertial Fusion

arXiv

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arXiv 2023年

作者： Li, Kailai Cao, Ziyu Hanebeck, Uwe D. The Division of Automatic Control Department of Electrical Engineering Linköping University Sweden The Intelligent Sensor-Actuator-Systems Laboratory Institute for Anthropomatics and Robotics Karlsruhe Institute of Technology Germany

We introduce a novel framework of continuous-time ultra-wideband-inertial sensor fusion for online motion estimation. Quaternion-based cubic cumulative B-splines are exploited for parameterizing motion states continuously over time. Systematic derivations of analytic kinematic interpolations and spatial differentiations are further provided. Based thereon, a new sliding-window spline fitting scheme is established for asynchronous multi-sensor fusion and online calibration. We conduct a dedicated validation of the quaternion spline fitting method, and evaluate the proposed system, SFUISE (spline fusion-based ultra-wideband-inertial state estimation), in real-world scenarios using public data set and experiments. The proposed sensor fusion system is real-time capable and delivers superior performance over state-of-the-art discrete-time schemes. We release the source code and own experimental data at https://***/KIT-ISAS/SFUISE . Copyright © 2023, The Authors. All rights reserved.

关键词： Motion estimation

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