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Corrigendum to “Experiment of proof-of-principle on prompt gamma-positron emission tomography (PG-PET) system for in-vivo dose distribution verification in proton therapy” [Nucl. Eng. Technol. 55 (2023) 2018–2025]

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Nuclear engineering and Technology 2024年第5期56卷 1942-1942页

作者： Bo-Wi Cheon Hyun Cheol Lee Sei Hwan You Hee Seo Chul Hee Min Hyun Joon Choi Department of Radiation Convergence Engineering Yonsei University 26493 Wonju South Korea Nuclear Materials Analysis Team Korea Institute of Nuclear Nonproliferation and Control Daejeon 34054 South Korea Department of Radiation Oncology Wonju Severance Christian Hospital Yonsei University Wonju College of Medicine Wonju South Korea Department of Quantum System Engineering Jeonbuk National University Jeonju South Korea

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Energy-Efficient Cell-Free Massive MIMO Through Sparse Large-Scale Fading Processing

arXiv

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arXiv 2022年

作者： Chen, Shuaifei Zhang, Jiayi Björnson, Emil Demir, Özlem Tuğfe Ai, Bo The School of Electronic and Information Engineering The Frontiers Science Center for Smart Highspeed Railway System Beijing Jiaotong University Beijing100044 China Purple Mountain Laboratories Nanjing211111 China The Department of Computer Science KTH Royal Institute of Technology Kista164 40 Sweden The Department of Electrical and Electronics Engineering TOBB University of Economics and Technology Ankara Turkey The State Key Laboratory of Rail Traffic Control and Safety Beijing Jiaotong University Beijing100044 China The Henan Joint International Research Laboratory of Intelligent Networking and Data Analysis Zhengzhou University Zhengzhou450001 China

Cell-free massive multiple-input multiple-output (CF mMIMO) systems serve the user equipments (UEs) by geographically distributed access points (APs) by means of joint transmission and reception. To limit the power consumption due to fronthaul signaling and processing, each UE should only be served by a subset of the APs, but it is hard to identify that subset. Previous works have tackled this combinatorial problem heuristically. In this paper, we propose a sparse distributed processing design for CF mMIMO, where the AP-UE association and long-term signal processing coefficients are jointly optimized. We formulate two sparsity-inducing mean-squared error (MSE) minimization problems and solve them by using efficient proximal approaches with block-coordinate descent. For the downlink, more specifically, we develop a virtually optimized large-scale fading precoding (V-LSFP) scheme using uplink-downlink duality. The numerical results show that the proposed sparse processing schemes work well in both uplink and downlink. In particular, they achieve almost the same spectral efficiency as if all APs would serve all UEs, while the energy efficiency is 2-4 times higher thanks to the reduced processing and signaling. Copyright © 2022, The Authors. All rights reserved.

关键词： Energy efficiency

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Local Partial Zero-Forcing Combining for Cell-Free Massive MIMO systems

arXiv

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arXiv 2022年

作者： Zhang, Jiayi Zhang, Jing Björnson, Emil Ai, Bo The School of Electronic and Information Engineering Beijing Jiaotong University Beijing100044 China The Frontiers Science Center for Smart High-Speed Railway System Beijing Jiaotong University Beijing100044 China The Department of Electrical Engineering Linköping University Linköping Sweden The Department of Computer Science KTH Royal Institute of Technology Kista Sweden The State Key Laboratory of Rail Traffic Control and Safety Beijing Jiaotong University Beijing100044 China The Frontiers Science Center for Smart High-Speed Railway System Henan Joint International Research Laboratory of Intelligent Networking and Data Analysis Zhengzhou University Zhengzhou450001 China Research Center of Networks and Communications Peng Cheng Laboratory Shenzhen China

Cell-free massive multiple-input multiple-output (MIMO) provides more uniform spectral efficiency (SE) for users (UEs) than cellular technology. The main challenge to achieve the benefits of cell-free massive MIMO is to realize signal processing in a scalable way. In this paper, we consider scalable full-pilot zero-forcing (FZF), partial FZF (PFZF), protective weak PFZF (PWPFZF), and local regularized ZF (LRZF) combining by exploiting channel statistics. We derive closed-form expressions of the uplink SE for FZF, PFZF, and PWPFZF combining with large-scale fading decoding over independent Rayleigh fading channels, taking channel estimation errors and pilot contamination into account. Moreover, we investigate the impact of the number of pilot sequences, antennas per AP, and APs on the performance. Numerical results show that LRZF provides the highest SE. However, PWPFZF is preferable when the number of pilot sequences is large and the number of antennas per AP is small. The reason is that PWPFZF has lower computational complexity and the SE expression can be computed in closed-form. Furthermore, we investigate the performance of PWPFZF combining with fractional power control and the numerical results show that it improves the performance of weak UEs and realizes uniformly good service for all UEs in a scalable fashion. Copyright © 2022, The Authors. All rights reserved.

关键词： Power control

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Energy-Constrained Computation Offloading in Space-Air-Ground Integrated Networks using Distributionally Robust Optimization

arXiv

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arXiv 2022年

作者： Chen, Yali Ai, Bo Niu, Yong Zhang, Hongliang Han, Zhu The State Key Laboratory of Rail Traffic Control and Safety Beijing Jiaotong University Beijing100044 China The Frontiers Science Center for Smart High-Speed Railway System Beijing Jiaotong University Beijing100044 China Henan Joint International Research Laboratory of Intelligent Networking and Data Analysis Zhengzhou University Zhengzhou450001 China Research Center of Networks and Communications Peng Cheng Laboratory Shenzhen China The National Mobile Communications Research Laboratory Southeast University Nanjing211189 China The Department of Electrical Engineering Princeton University PrincetonNJ08544 United States The Department of Electrical and Computer Engineering The University of Houston HoustonTX77004 United States The Department of Computer Science and Engineering Kyung Hee University Seoul446-701 Korea Republic of

With the rapid development of connecting massive devices to the Internet, especially for remote areas without cellular network infrastructures, space-air-ground integrated networks (SAGINs) emerge and offload computation-intensive tasks. In this paper, we consider a SAGIN, where multiple low-earthorbit (LEO) satellites providing connections to the cloud server, an unmanned aerial vehicle (UAV), and nearby base stations (BSs) providing edge computing services are included. The UAV flies along a fixed trajectory to collect tasks generated by Internet of Things (IoT) devices, and forwards these tasks to a BS or the cloud server for further processing. To facilitate efficient processing, the UAV needs to decide where to offload as well as the proportion of offloaded tasks. However, in practice, due to the variability of environment and actual demand, the amount of arrival tasks is uncertain. If the deterministic optimization is utilized to develop offloading strategy, unnecessary system overhead or higher task drop rate may occur, which severely damages the system robustness. To address this issue, we characterize the uncertainty with a data-driven approach, and formulate a distributionally robust optimization problem to minimize the expected energy-constrained system latency under the worst-case probability distribution. Furthermore, the distributionally robust latency optimization algorithm is proposed to reach the suboptimal solution. Finally, we perform simulations on the realworld data set, and compare with other benchmark schemes to verify the efficiency and robustness of our proposed algorithm. Copyright © 2022, The Authors. All rights reserved.

关键词： Probability distributions

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[Retracted] IOT and Blockchain-Based Cloud Model for Secure Data Transmission for Smart City

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Security and Communication Networks 2023年第1期2023卷

作者： Liwa H. Al-Farhani Yahya Alqahtani Hamdan Ali Alshehri R. John Martin Sachin Lalar Rituraj Jain System Analysis Control and Information Processing Academy of Engineering RUDN University Moscow Russiarudn.ru Faculty of Computer Science and Information Technology Jazan University Saudi Arabiajazanu.edu.sa Department of Computer Science and Applications Kurukshetra University Kurukshetra Indiakuk.ac.in Department of Electrical and Computer Engineering Wollega University Nekemte Ethiopiawollegauniversity.edu.et

The widespread use of the Internet of Things (IoT) technology has both good and bad things about it. There must be a full and reliable security system in place for the Internet of Things so that things can work together in a safe way and intrusions cannot happen. There are now many more ways to keep the Internet of Things safe, thanks to a detecting system. As machine learning and deep learning technologies have become better, a lot of good intrusion detection systems have been made. This kind of study is covered. These two types of security are compared in this study. The current machine-based intrusion detection system is broken down into more detailed categories based on detection technology, data source, architecture, and operating method. These categories are as follows: It is talked about how IoT security will grow in the future and how to understand its intrusion detection system too. In this paper, a cloud-based blockchain security model has been presented for secure data transmission over IoT.

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State of Charge Estimation of Parallel Connected Battery Cells via Descriptor system Theory

State of Charge Estimation of Parallel Connected Battery Cel...

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American control Conference

作者： Dong Zhang Luis D. Couto Sebastien Benjamin Wente Zeng Daniel F. Coutinho Scott J. Moura Department of Civil and Environmental Engineering University of California Berkeley California USA Department of Control Engineering and System Analysis Université Libre de Bruxelles Brussels Belgium Saft Batteries Total S.A. Total S.A. Department of Automation and Systems UFSC Florianópolis SC Brazil

ISBN: (数字)9781538682661

ISBN: (纸本)9781538682678

This manuscript presents an algorithm for individual Lithium-ion (Li-ion) battery cell state of charge (SOC) estimation when multiple cells are connected in parallel, using only terminal voltage and total current measurements. For battery packs consisting of thousands of cells, it is desirable to estimate individual SOCs by only monitoring the total current in order to reduce sensing cost. Mathematically, series connected cells yield dynamics given by ordinary differential equations under classical full voltage sensing. In contrast, parallel connected cells are evidently more challenging because the dynamics are governed by a nonlinear descriptor system, including differential equations and algebraic equations arising from voltage and current balance across cells. This paper designs and analyzes an observer with linear output error injection, where the individual cell SOCs and local currents are locally observable from the total current and voltage measurements. The asymptotic convergence of differential and algebraic states is established by considering local Lipschitz continuity property of system nonlinearities. Simulation results on LiNiMnCoO_2/Graphite (NMC) cells illustrate convergence for SOCs, local currents, and terminal voltage.

关键词： Batteries Mathematical model State of charge Observers Current measurement Integrated circuit modeling

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Expert Search Framework for the Task of Building an Expert Panel in Educational Organizations

Expert Search Framework for the Task of Building an Expert P...

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Ural Symposium on Biomedical engineering, Radioelectronics and Information Technology (USBEREIT)

作者： Andrey Sozykin Tatiana Oreskhina Alexander Detkov Evgeniy Komockiy Engineering School of IT Telecom and Control Systems Ural Federal University Yekaterinburg Russia Institute of Fundamental Education Ural Federal University Yekaterinburg Russia Department Of System Analysis And Decision Making Ural Federal University Yekaterinburg Russia

ISBN: (数字)9781728131658

ISBN: (纸本)9781728131665

Development of curriculum in the universities, and search of good-skilled experts to evaluate project education results consume large amounts of time for faculty members. The article proposes a universal framework that facilitates this task by automating the process of finding companies that can provide such experts. The proposed approach is characterized by a high degree of automation and formalization, because it uses the data of financial statements of companies in a given industry in its work. Thanks to the use of statistical data and methods, the objectivity and reliability of the search for experts increases. As data source uses the data set “Accounting (financial) statements of enterprises and organizations for 2018” provided by Rosstat. The proposed approach was successfully tested in the course of attracting experts to evaluate the results of a design workshop for students of the Ural Federal University in 2019. During testing, the top 40 IT companies of the Sverdlovsk region were selected. From the 40 organizations, 7 companies agreed to respond to the proposal, which determined to 17.5% of the sample. At the same time, 19 experts were sent from this organizations, which amounted to 65.5 % of all exerts who agreed to participate in the event. Thus, the proposed approach can significantly expand the composition of the expert base and attract experts based on a strictly formalized, objective approach.

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Optimal DTC control strategy of DFIG using variable gain PI and hysteresis controllers adjusted by PSO algorithm

Periodica polytechnica Electrical engineering and computer s...

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Periodica polytechnica Electrical engineering and computer science 2020年第1期64卷 74-86页

作者： Amer, Mokhtar Miloudi, Abdallah Lakdja, Fatiha Geometry Analysis Control and Applications Laboratory Department of Electrical Engineering Faculty of Technology Dr Tahar Moulay University of Saida P. O. B 138 Ennasr Saida20000 Algeria Intelligent Control and Electrical Power System Laboratory Department of Electrical Engineering Faculty of Technology Dr Tahar Moulay University of Saida P. O. B 138 Ennasr Saida20000 Algeria

This paper presents an optimal Direct Torque control (DTC) strategy for Doubly Fed Induction Generator based wind turbine. The proposed strategy is considered based on Particle Swarm Optimization (PSO) Algorithm. The PSO is found to be robust and fast in solving nonlinear problems. Motivation for application of PSO approach is to overcome the limitation of the conventional controllers design, which cannot guarantee satisfactory control performance when designed by trial and error. In this work PSO algorithm was used to adjust the hysteresis torque and flux comparators bandwidths and to tune the parameters of Variable Gain PI (VGPI) controller designed for Maximum Power Point Tracking (MPPT) speed control of wind turbine to ensure high performance torque control. The optimal control strategy is considered in detail and it is shown that the use of the optimized controllers reduces rotor flux and electromagnetic torque ripples and improves the system dynamic performances. The effectiveness of the proposed direct torque control based on PSO algorithm (optimal DTC) method is illustrated through simulations on 1.5 MW DFIG based wind turbine. Simulation results illustrate the improved performances of optimal DTC compared with the conventional DTC. © 2020 Budapest University of Technology and Economics. All rights reserved.

关键词： Asynchronous generators

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Constrained Extremum Seeking: a Modified-Barrier Function Approach ⁎

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IFAC-PapersOnLine 2019年第16期52卷 694-699页

作者： Christophe Labar Emanuele Garone Michel Kinnaert Christian Ebenbauer Department of Control Engineering and System Analysis Université libre de Bruxelles 1050 Brussels Belgium Institute for Systems Theory and Automatic Control University of Stuttgart 70569 Stuttgart Germany

In this paper, we address the problem of steering the input of a convex function to a value that minimizes the function under a convex constraint. We consider the case where the constraint cannot be violated of more than a user-defined value during the whole transient phase. The mathematical expression of both the cost function and the constraint are assumed to be unknown. The only information available are the on-line values of the cost and the constraint. To tackle this problem, an optimization law, based on a modified-barrier function, and involving the gradient of both the cost function and the constraint, is firstly designed. The Lie bracket formalism is then exploited to approximate this law, by combining time-periodic signals with the on-line measurements of both the cost and the constraint. The stability property of the resulting constrained extremum seeking system is proved, and its effectiveness is shown in simulation.

关键词： Constrained Optimization Extremum Seeking Singular Perturbations Data-based control Modified Barrier-Function

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Mathematical Methods for Detecting and Localizing Failures in Complex Hardware/Software systems

Mathematical Methods for Detecting and Localizing Failures i...

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International Conference on Advanced Computer Information Technologies (ACIT)

作者： Olena Syrotkina Oleksandr Aziukovskyi Iryna Udovyk Oleksii Aleksieiev Serhii Prykhodchenko Leonid Ilyin Department of Software Engineering Dnipro University of Technology Dnipro Ukraine Department of Electric Drive Dnipro University of Technology Dnipro Ukraine Department of System Analysis and Control Dnipro University of Technology Dnipro Ukraine Department of Tourism and Hospitality Lesya Ukrainka Eastern European National University Lutsk Ukraine

ISBN: (数字)9781728167602

ISBN: (纸本)9781728167619

This article addresses the problem of creating and applying methods of automatic failure self-diagnostics in complex hardware/software systems (SCADA systems included). We conducted a review of modern methodologies used for solving problems of this class. A structural-logical model was proposed to describe the system's architecture. We developed a mathematical method for diagnosing failures based on analysing changes in the state of system information flows. This included failure diagnostic criteria for the method we developed. As a result, it allowed us to obtain the analytical functional dependencies for the detection and localization of failures in the system's structural modules. Graphs are presented to illustrate the probability of the system's non-failure versus time-of-failure detection and localization. We obtained logical conclusions about improving the quality of system functions using the methods we developed for automatic failure self-diagnostics.

关键词： Servers SCADA systems Real-time systems Data communication Data models Fault diagnosis

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