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SSRN 2022年

作者： Nikolaidis, Theoklis Jafari, Soheil Sibilli, Thierry Kipouros, Timoleon Ayat, Sabrina Isikveren, Askin Centre for Propulsion and Thermal Power Engineering Cranfield University BedfordMK43 0AL United Kingdom Airbus Operations GmbH Kreetslag 10 HamburgD-21129 Germany Formerly Company Expert on Thermal Systems SAFRAN Tech Safran Paris Saclay France SAFRAN Paris Saclay Châteaufort CS 80112 Magny-les-Hameaux78772 France SAFRAN S.A. c/o Aerospace Embedded Solutions GmbH Munich80639 Germany Reader in Gas Turbine Performance and Numerical Simulation Centre for Propulsion Engineering and Power United Kingdom Lecturer in Gas Turbine Thermal Management and Control Centre for Propulsion Engineering and Power United Kingdom Hydrogen Fuel System Development Engineer Airbus Operations GmbH Kreetslag 10 HamburgD-21129 Germany Formerly Company Expert on Thermal Systems SAFRAN Tech Safran Paris France Senior Lecturer in Computational Engineering Design Optimisation Centre for Propulsion Engineering and Power United Kingdom Research Engineer Electrical & Electronic Systems Group Safran Tech SAFRAN Paris Saclay France Advanced Aircraft Concepts and Energy Systems Senior Group Expert Integrated Aircraft Systems and Operations SAFRAN Tech France

New generation of propulsion systems are increasingly complex with higher requirements on engines for efficiency, thrust and power generation. As a side effect, the produced thermal loads are higher, imposing limitations on the air vehicle performance. The current paper offers a novel methodology for thermal management system architecture design for high power hybrid electric propulsion systems. Four cases are investigated including state-of-the-art conventional thermal management system, pre-heated two-phase thermal management system, utilizing thermally neutral heat transfer fluids in a two-phase cooling mechanism, and a combination of single- and two-phase thermal management system architectures. For this purpose, a Vertical Take-Off and Landing multi-mission aircraft is selected as the case study in which the existing mechanically driven lift fan is replaced by an electric fan to replicate a high-power hybrid electric propulsion system of the future generation. The results confirm that the performance of the pre-heated two-phase thermal management system surpasses the other cases without exceeding the temperature limit. On the contrary, the state-of-the-art conventional system can operate only for 70 seconds. So, the results confirm the effectiveness of the proposed thermal management system architecture in dealing with MW scale thermal loads generated by next generation high power hybrid electric propulsion systems. © 2022, The Authors. All rights reserved.

关键词： Temperature control

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Integrated carbon and nitrogen management for cost-effective environmental policies in China

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Science (New York, N.Y.) 2025年第6751期388卷 1098-1103页

作者： Xin Xu Xiuming Zhang Yiyang Zou Tianrun Chen Jingfang Zhan Luxi Cheng Wilfried Winiwarter Shaohui Zhang Peter M Vitousek Wim de Vries Baojing Gu State Key Laboratory of Soil Pollution Control and Safety Zhejiang University Hangzhou China. College of Environmental and Resource Sciences Zhejiang University Hangzhou China. International Institute for Applied Systems Analysis Laxenburg Austria. Ministry of Education Key Laboratory of Environment Remediation and Ecological Health Zhejiang University Hangzhou China. College of Computer Science and Technology Zhejiang University Hangzhou China. Policy Simulation Laboratory Zhejiang University Hangzhou China. Institute of Environmental Engineering University of Zielona Góra Zielona Góra Poland. School of Economics and Management Beihang University Beijing China. Department of Earth System Science Stanford University Stanford CA USA. Wageningen University and Research Earth Systems and Global Change Group Wageningen Netherlands. Zhejiang Provincial Key Laboratory of Agricultural Resources and Environment Zhejiang University Hangzhou China.

Carbon and nitrogen are central elements in global biogeochemical cycles. To effectively manage carbon and nitrogen in China, we developed a comprehensive model for quantifying their fluxes, investigating their interplay across 16 human and natural subsystems. Between 1980 and 2020, nitrogen losses in China increased 2.3-fold and carbon emissions surged 6.5-fold. Integrated carbon and nitrogen management holds the potential for a 74% reduction in nitrogen losses to air and water and a 91% decrease in carbon emissions to the atmosphere by 2060. Compared with separate control of carbon or nitrogen, integrated management delivers an additional reduction of 1.8 million tons of nitrogen and 26.5 million tons of carbon by 2060, bringing out a 37% decrease in unit abatement cost and a net societal benefit of 1384 billion USD.

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On the Role of Models in Learning control: Actor-Critic Iterative Learning control

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IFAC-PapersOnLine 2020年第2期53卷 1450-1455页

作者： Maurice Poot Jim Portegies Tom Oomen Control Systems Technology Group Dept. of Mechanical Engineering Eindhoven University of Technology Eindhoven The Netherlands CASA Dept. of Mathematics and Computer Science Eindhoven University of Technology Eindhoven The Netherlands

Learning from data of past tasks can substantially improve the accuracy of mechatronic systems. Often, for fast and safe learning a model of the system is required. The aim of this paper is to develop a model-free approach for fast and safe learning for mechatronic systems. The developed actor-critic iterative learning control (ACILC) framework uses a feedforward parameterization with basis functions. These basis functions encode implicit model knowledge and the actor-critic algorithm learns the feedforward parameters without explicitly using a model. Experimental results on a printer setup demonstrate that the developed ACILC framework is capable of achieving the same feedforward signal as preexisting model-based methods without using explicit model knowledge.

关键词： Feedforward control iterative learning control learning algorithms reinforcement learning Markov decision problems function-approximation model-free control model-based control

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Model-based electron density profile estimation and control, applied to ITER

arXiv

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arXiv 2021年

作者： Bosman, Thomas van Berkel, M. de Baar, M.R. DIFFER - Dutch Institute for Fundamental Energy Research PO Box 6336 Eindhoven5600HH Netherlands Eindhoven University of Technology Dept. of Mechanical Engineering Control Systems Technology Group PO Box 513 Eindhoven5600MB Netherlands

In contemporary magnetic confinement devices, the density distribution is sensed with interferometers and actuated with feedback controlled gas injection and open-loop pellet injection. This is at variance with the density control for ITER and DEMO, that will depend mainly on pellet injection as an actuator in feed-back control. This paper presents recent developments in state estimation and control of the electron density profile for ITER using relevant sensors and actuators. As a first step, Thomson scattering is included in an existing dynamic state observer. Second, model predictive control is developed as a strategy to regulate the density profile while avoiding limits associated with the total density (Greenwald limit) or gradients in the density distribution (e.g. neoclassical impurity transport). Simulations show that high quality density profile estimation can be achieved with Thomson Scattering and that the controller is capable of regulating the distribution as desired. Copyright © 2021, The Authors. All rights reserved.

关键词： Light scattering

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Linear Parameter-Varying control of Nonlinear systems based on Incremental Stability ⁎

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IFAC-PapersOnLine 2019年第28期52卷 38-43页

作者： P.J.W. Koelewijn R. Tóth H. Nijmeijer Control Systems Group Department of Electrical Engineering Dynamics and Control Group Department of Mechanical Engineering Eindhoven University of Technology 5612 AE Eindhoven The Netherlands

The Linear Parameter-Varying (LPV) framework has long been used to guarantee performance and stability requirements of nonlinear (NL) systems mainly through the L 2 -gain concept. However, recent research has pointed out that current L 2 -gain based LPV synthesis methods can fail to guarantee these requirements if stabilization of a non-zero operating condition (e.g. reference tracking, constant disturbance rejection, etc.) is required. In this paper, an LPV based synthesis method is proposed which is able to guarantee incremental performance and stability of an NL system even with reference and disturbance rejection objectives. The developed approach and the current L 2 LPV synthesis method are compared in a simulation study of the position control problem of a Duffing oscillator, showing performance improvements of the proposed method compared to the current L 2 -based approach for tracking and disturbance rejection.

关键词： Nonlinear systems Stability Stabilization Optimal control

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Collective iterative learning control: Exploiting diversity in multi-agent systems for reference tracking tasks

arXiv

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arXiv 2021年

作者： Meindl, Michael Molinari, Fabio Lehmann, Dustin Seel, Thomas Embedded Mechatronics Laboratory Hochschule Karlsruhe Karlsruhe76133 Germany Control Systems Group Technische Universität Berlin Berlin10587 Germany Department of Artificial Intelligence in Biomedical Engineering Friedrich-Alexander-Universität Erlangen–Nürnberg Erlangen91052 Germany

Multi-agent systems (MASs) can autonomously learn to solve previously unknown tasks by means of each agent’s individual intelligence as well as by collaborating and exploiting collective intelligence. This article considers a group of autonomous agents learning to track the same given reference trajectory in a possibly small number of trials. We propose a novel collective learning control method that combines iterative learning control (ILC) with a collective update strategy. We derive conditions for desirable convergence properties of such systems. We show that the proposed method allows the collective to combine the advantages of the agents’ individual learning strategies and thereby overcomes trade-offs and limitations of single-agent ILC. This benefit is achieved by designing a heterogeneous collective, i.e., a different learning law is assigned to each agent. All theoretical results are confirmed in simulations and experiments with two-wheeled-inverted-pendulum robots (TWIPRs) that jointly learn to perform the desired maneuver. Copyright © 2021, The Authors. All rights reserved.

关键词： Two term control systems

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On Representations of Linear Dynamic Networks

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IFAC-PapersOnLine 2018年第15期51卷 838-843页

作者： Kivits, E.M.M. den Hof, Paul M.J. Van Control Systems Group Department of Electrical Engineering Eindhoven University of Technology Netherlands

Linear dynamic networks are typically described in either a state-space form or a module representation. The question is addressed under which conditions these representations are equivalent and can be transformed into one another. Hidden states and especially shared hidden states have a central position in this analysis. A consequence for identification is that MIMO parameterised modules may be necessary in order to appropriately take care of shared hidden states. Further, the construction of sub-networks in a linear dynamic network resulting in a module representation is illustrated. The module dynamic network allows to zoom in/out on/of the network to include/exclude more detailed structural information. Zooming in and out is respectively described by realisation and multi-path immersion. © 2018

关键词： Linear networks Identification (control systems) State space methods Dynamic network Hidden state Linear dynamics Multipaths State space form Structural information Sub network Zooming in

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Temperature shift of magnetic field dependent photoluminescence features of nitrogen-vacancy ensembles in diamond

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Physical Review B 2025年第9期111卷 094112-094112页

作者： Irena Rodzoń Xue Zhang Viktor Ivády Huijie Zheng Arne Wickenbrock Dmitry Budker Johannes Gutenberg-Universität Mainz Helmholtz-Institut Mainz GSI Helmholtzzentrum für Schwerionenforschung 55128 Mainz Germany School of Control Science and Engineering Dalian University of Technology Dalian 116024 China Department of Physics of Complex Systems ELTE Eötvös Loránd University Egyetem tér 1-3 H-1053 Budapest Hungary MTA-ELTE Lendület “Momentum” NewQubit Research Group Pázmány Péter Sétány 1/A 1117 Budapest Hungary Department of Physics Chemistry and Biology Linköping University 581 83 Linköping Sweden Beijing National Laboratory for Condensed Matter Physics Institute of Physics Chinese Academy of Sciences Beijing 100190 China Department of Physics University of California Berkeley California 94720 USA

Recently significant attention has been paid to magnetic field dependent photoluminescence (PL) features of the negatively charged nitrogen-vacancy (NV) centers in diamond. These features are used for microwave-free sensing and are indicative of the spin-bath properties in the diamond sample. Examining the temperature dependence of the PL features allows identifying both temperature-dependent and -independent features, of potential utility in diamond-based quantum sensing and dynamic nuclear polarization applications. Here we study the thermal variability of many different features visible in a wide range of magnetic fields. To this end, we first discuss the origin of the features and tentatively assign the previously unidentified features to cross relaxation of NV center containing multispin systems. The experimental results are compared with theoretically predicted temperature shifts deduced from a combination of thermal expansion and electron-phonon interactions. A deeper insight into the thermal behavior of a wide array of the features may come with important consequences for various applications in high-precision NV thermometry, gyroscopes, solid-state clocks, and biomagnetic measurements.

关键词： Electron-phonon interactions

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Walking control Based on Step Timing Adaptation

Walking Control Based on Step Timing Adaptation

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作者： Khadiv, Majid Herzog, Alexander Moosavian, S. Ali. A. Righetti, Ludovic Righetti, Ludovic Movement Generation and Control Group Max-Planck Institute for Intelligent Systems Tuebingen72076 Germany Google X Mountain ViewCA94043 United States Department of Mechanical Engineering K. N. Toosi University of Technology Tehran*** Iran Department of Electrical and Computer Engineering New York University BrooklynNY11201 United States

Step adjustment can improve the gait robustness of biped robots;however, the adaptation of step timing is often neglected as it gives rise to nonconvex problems when optimized over several footsteps. In this article, we argue that it is not necessary to optimize walking over several steps to ensure gait viability and show that it is sufficient to merely select the next step timing and location. Using this insight, we propose a novel walking pattern generator that optimally selects step location and timing at every control cycle. Our approach is computationally simple compared to standard approaches in the literature, yet guarantees that any viable state will remain viable in the future. We propose a swing foot adaptation strategy and integrate the pattern generator with an inverse dynamics controller that does not explicitly control the center of mass nor the foot center of pressure. This is particularly useful for biped robots with limited control authority over their foot center of pressure, such as robots with point feet or passive ankles. Extensive simulations on a humanoid robot with passive ankles demonstrate the capabilities of the approach in various walking situations, including external pushes and foot slippage, and emphasize the importance of step timing adaptation to stabilize walking. © 2004-2012 IEEE.

关键词： Anthropomorphic robots

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The Regulation of a Quadrotor UAV Carrying a Pendulum using Receding Horizon control

The Regulation of a Quadrotor UAV Carrying a Pendulum using ...

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International Conference on Information Technology and Electrical engineering (ICITEE)

作者： Tua A. Tamba Yul Y. Nazaruddin Endang Juliastuti Center for Control Automation & Systems Engineering Parahyangan Catholic University Bandung Indonesia National Center for Sustainable Transportation Technology Bandung Indonesia Instrumentation & Control Research Group Institut Teknologi Bandung

ISBN: (数字)9781728110974

ISBN: (纸本)9781728110981

This paper proposes an approach for regulating the stability of an inverted pendulum that is attached on top of a moving quadrotor UAV. The approach is based on the receding horizon control scheme whose objective is to stabilize the pendulum in a vertical position while the quadrotor UAV is moving from predetermined initial to final poses. More specifically, the approach formulates a parametric quadratic optimization of the simultaneous stabilization of both the inverted pendulum and the quadrotor UAV. Simulation results are presented to demonstrate the successful implementation of the proposed method.

关键词： Optimization Regulation Mathematical model Electrical engineering Vehicle dynamics Task analysis Simulation

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