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Limitations on control performance in the Czochralski crystal growth process using bright ring measurement as a controlled variable ⁎

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IFAC-PapersOnLine 2019年第14期52卷 129-134页

作者： Halima Zahra Bukhari Morten Hovd Jan Winkler Department of Engineering Cybernetics NTNU Trondheim Norway Institute of Control Theory Faculty of Electrical & Computer Engineering TU Dresden Germany

This paper develops a dynamical model for crystal diameter in the Czochralski process for production of monocrystalline silicon. The model combines simplified crystal growth dynamics with rigorous ray tracing to describe the camera image used for diameter control, and it is demonstrated that the resulting model captures the so-called measurement anomaly that represents a key performance limitation for crystal diameter control.

关键词： Czochralski process bright ring measurement right half plane zero ray tracing interface dynamics

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Influence of CO 2 Injection Timing on Enhanced Coalbed Methane Recovery Using Thermo-Hydro-Mechanical Coupled Model

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Case Studies in Thermal engineering 2025年

作者： Hexiang Xu Cheng Zhai Jizhao Xu Yong Sun Ting Liu Yangfeng Zheng Hongyang Xu Ting Huang State Key Laboratory of Coal Mine Disaster Prevention and Control China University of Mining and Technology Xuzhou 221116 China Key Laboratory of Theory and Technology on Coal and Rock Dynamic Disaster Prevention and Control National Mine Safety Administration China University of Mining and Technology Xuzhou 221116 China School of Safety Engineering China University of Mining and Technology Xuzhou 221116 China School of Low Carbon Energy and Power Engineering China University of Mining and Technology Xuzhou 221116 China Jiangsu Key Laboratory of Coal-based Greenhouse Gas Control and Utilization China University of Ming and Technology Xuzhou 221008 Jiangsu China Carbon Neutrality Institute China University of Mining and Technology Xuzhou 221008 Jiangsu China

Delayed CO 2 injection can prevent premature CO 2 breakthrough to production wells during CO 2 enhanced coalbed methane (CO 2 -ECBM) recovery. Currently, the influence of CO 2 injection timing on CO 2 -ECBM recovery is unclear. In this paper, the thermo-hydro-mechanical (THM) coupled model was established to investigate the CO 2 -ECBM recovery with different injection timings. The porosity evolution characterization and the optimal injection timing was determined. The results show that high-pressure CO 2 injection elevates reservoir pressure and enhances CH 4 production. As injection time increases, reservoir temperature rises, and permeability declines. Delayed CO 2 injection can avoid inefficient injection stage and maintain a higher injection rate. Injection timing showed linear correlations with CH 4 production, CO 2 storage volume, and breakthrough time, and an S-shaped trend with final CH 4 concentration. CO 2 injection shortens the pore pressure-dominated control stage of porosity and amplifies the influence of gas ad/desorption-induced strain. Temperature changes have a minor effect on porosity, but high initial temperature can reduce gas adsorption, significantly affecting porosity. Finally, the optimal injection time was determined as 1000 d. The results are beneficial for improving the CH 4 recovery and realizing the efficient CO 2 storage.

关键词： Thermo-hydro-mechanical coupled model CO 2 -ECBM injection timing delayed CO 2 injection CH 4 production

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A Dueling-Double-Deep Q-Network controller for Magnetic Levitation Ball System

A Dueling-Double-Deep Q-Network Controller for Magnetic Levi...

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Chinese control Conference (CCC)

作者： Yefeng Yang Xiaojun Ban Xianlin Huang Chenghao Shan Center for Control Theory and Guidance Technology Harbin Institute of Technology Harbin P. R. China Institute of Marine Navigation Technology Harbin Engineering University Harbin P. R. China

ISBN: (数字)9789881563903

ISBN: (纸本)9781728165233

Deep reinforcement learning technique has attracted extensive attention in the field of control with the rapid development of artifical intelligence. Model-free control methods perform more effcient than traditional model-based control method for complex nonlinear system since they don't require accurate models. In this study, by using the Dueling-Double-DQN (Dueling-DDQN, 3-DQN) algorithm, a self-learning controller is developed for the magnetic levitation ball system. The numerical simulation demonstrates the effectiveness of our controller. Moreover, we compare the above controller with the DQN-based self-learning controller. Numerical simulation shows that the attraction domain of the Dueling-DDQN controller is larger that the latter.

关键词： Mathematical model Magnetic levitation Artificial neural networks control systems Machine learning Voltage control Training

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Hardware-in-the-Loop-Simulation of the light distribution of automotive Matrix-LED-Headlights*

Hardware-in-the-Loop-Simulation of the light distribution of...

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IEEE/ASME (AIM) International Conference on Advanced Intelligent Mechatronics

作者： Mirko Waldner Maximilian Krämer Torsten Bertram Institute of Control Theory and Systems Engineering TU Dortmund University Dortmund Germany

This contribution proposes a novel Hardware-in-the-Loop (HiL)-simulation of the light distribution of matrix-headlights to reduce the duration and number of real night test drives. After calibration machine vision cameras measure and digitize the light distribution of the real matrix-headlight in the lab. The calibration process compares the light distribution measured by the camera with the absolute intensity-data from a goniophotometer. Minimizing the error determines the optimal transformation parameters. A virtual testing simulation visualizes the digitized light distribution under consideration of the actual driving dynamics. The HiL-simulation generates the control data for the real headlight. The evaluation of the approach uses a real matrix-headlight with 84 pixels and its measured intensity distribution as the reference. The system is real-time capable and the light distribution in the simulation matches the original headlight in intensity and color.

关键词： Image color analysis Light sources Cameras Vehicle dynamics Real-time systems Light emitting diodes

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Extremum seeking algorithms based on non-commutative maps 11

Extremum seeking algorithms based on non-commutative maps

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11th IFAC Symposium on Nonlinear control Systems, NOLCOS 2019

作者： Feiling, Jan Labar, Christophe Grushkovskaya, Victoria Garone, Emanuele Kinnaert, Michel Ebenbauer, Christian Institute for Systems Theory and Automatic Control University of Stuttgart Germany Dr. Ing. h.c. F. Porsche AG Stuttgart Germany Department of Control Engineering and System Analysis Université libre de Bruxelles Belgium Institute for Mathematics Julius-Maximilians-University Würzburg Germany

In this work, discrete-time extremum seeking algorithms for unconstrained optimization problems are developed. A general class of non-commutative maps and one- and two point function evaluation polices are presented to approximate a gradient-descent algorithm, suitable for extremum seeking problems. Moreover, adaptive step size rules are discussed to achieve faster convergence and vanishing steady state oscillations. © 2019, IFAC (International Federation of Automatic control) Hosting by Elsevier Ltd. All rights reserved.

关键词： Optimization

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Confinement and collective escape of active particles

arXiv

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arXiv 2021年

作者： Aranson, Igor S. Pikovsky, Arkady Department of Biomedical Engineering Chemistry and Mathematics Penn State University University ParkPA16802 United States Institute for Physics and Astronomy University of Potsdam Karl-Liebknecht-Strasse 24/25 Potsdam-Golm14476 Germany Department of Control Theory Nizhny Novgorod State University Gagarin Avenue 23 Nizhny Novgorod606950 Russia

Active matter broadly covers the dynamics of self-propelled particles. While the onset of collective behavior in homogenous active systems is relatively well understood, the effect of inhomogeneities such as obstacles and traps lacks overall clarity. Here, we study how interacting self-propelled particles become trapped and released from a trap. We have found that captured particles aggregate into an orbiting condensate with a crystalline structure. As more particles are added, the trapped condensate escape as a whole. Our results shed light on the effects of confinement and quenched disorder in active matter. © 2021, CC BY.

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Derivation and Application of an Observer Structure to Detect Inconsistencies Within a Static Environmental Model 1

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4. Internationale ATZ-Fachtagung Automatisiertes Fahren, 2018

作者： Lütkemöller, Moritz Oeljeklaus, Malte Bertram, Torsten Rink, Klaus Stählin, Ulrich Grewe, Ralph Institute of Control Theory and Systems Engineering TU Dortmund Dortmund Germany Continental Chassis & Safety Passive Safety & Sensorics Frankfurt Germany Advanced Engineering Continental Chassis & Safety Frankfurt Germany

ISBN: (数字)9783658237516

ISBN: (纸本)9783658237509

Smart vehicles like autonomously driving cars have the advantage to make a ride more safe and comfortable because intelligent vehicles respond better and faster than human beings to critical situations [1]. Having accurate knowledge of its environment is essential for a car that drives autonomously. Based on this, a maneuver adapted to the situation can be planned and carried out. The perception takes place via a variety of sensors such as cameras, radars and LIDAR's [2, 3]. However, the disadvantage of an intelligent vehicle is the complex infrastructure consisting of sensors, ECUs, communication equipment, etc. that is needed to perceive the environment correctly. As the complexity increases, the susceptibility to errors of such a system increases the same way. Errors refer to the failure of individual units, the incorrect processing of information, but also the manipulative interference of unauthorized persons.. © Springer Fachmedien Wiesbaden GmbH, ein Teil von Springer Nature 2019.

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Traceable random numbers from a nonlocal quantum advantage

arXiv

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arXiv 2024年

作者： Kavuri, Gautam A. Palfree, Jasper Reddy, Dileep V. Zhang, Yanbao Bienfang, Joshua C. Mazurek, Michael D. Alhejji, Mohammad A. Siddiqui, Aliza U. Cavanagh, Joseph M. Dalal, Aagam Abellán, Carlos Amaya, Waldimar Mitchell, Morgan W. Stange, Katherine E. Beale, Paul D. Brandão, Luís T.A.N. Booth, Harold Peralta, René Nam, Sae Woo Mirin, Richard P. Stevens, Martin J. Knill, Emanuel Shalm, Lynden K. Department of Physics University of Colorado BoulderCO80309 United States The National Institute of Standards and Technology BoulderCO80305 United States Quantum Information Science Section Computational Sciences and Engineering Division Oak Ridge National Laboratory Oak RidgeTN37831 United States Joint Quantum Institute National Institute of Standards and Technology University of Maryland 100 Bureau Drive GaithersburgMD20899 United States Center for Quantum Information and Control University of New Mexico AlbuquerqueNM87131 United States Department of Electrical Computer and Energy Engineering University of Colorado BoulderCO80309 United States Physical Measurement Laboratory National Institute of Standards and Technology GaithersburgMD20899 United States Quside Technologies S.L. Castelldefels Barcelona Spain ICFO-Institut de Ciencies Fotoniques The Barcelona Institute of Science and Technology Castelldefels Barcelona08860 Spain ICREA - Institució Catalana de Recerca i Estudis Avançats Barcelona08010 Spain Department of Mathematics University of Colorado BoulderCO80309 United States GaithersburgMD20899 United States Information Technology Laboratory National Institute of Standards and Technology GaithersburgMD20899 United States Physical Measurement Laboratory National Institute of Standards and Technology BoulderCO80305 United States Center for Theory of Quantum Matter University of Colorado BoulderCO80305 United States Applied and Computational Mathematics Division National Institute of Standards and Technology BoulderCO80305 United States Quantum Engineering Initiative Department of Electrical Computer and Energy Engineering University of Colorado BoulderCO80309 United States

The unpredictability of random numbers is fundamental to both digital security [1, 2] and applications that fairly distribute resources [3, 4]. However, existing random number generators have limitations—the generation processes cannot be fully traced, audited, and certified to be unpredictable. The algorithmic steps used in pseudorandom number generators [5] are auditable, but they cannot guarantee that their outputs were a priori unpredictable given knowledge of the initial seed. Device-independent quantum random number generators [6–9] can ensure that the source of randomness was unknown beforehand, but the steps used to extract the randomness are vulnerable to tampering. Here, for the first time, we demonstrate a fully traceable random number generation protocol based on device-independent techniques. Our protocol extracts randomness from unpredictable non-local quantum correlations, and uses distributed intertwined hash chains to cryptographically trace and verify the extraction process. This protocol is at the heart of a public traceable and certifiable quantum randomness beacon that we have launched [10]. Over the first 40 days of operation, we completed the protocol 7434 out of 7454 attempts—a success rate of 99.7%. Each time the protocol succeeded, the beacon emitted a pulse of 512 bits of traceable randomness. The bits are certified to be uniform with error times actual success probability bounded by 2−64. The generation of certifiable and traceable randomness represents one of the first public services that operates with an entanglement-derived advantage over comparable classical approaches. Copyright © 2024, The Authors. All rights reserved.

关键词： Random number generation

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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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One-half reflected entropy is not a lower bound for entanglement of purification

arXiv

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arXiv 2023年

作者： Couch, Josiah Nguyen, Phuc Racz, Sarah Stratis, Georgios Zhang, Yuxuan Beth Israel Deaconess Medical Center BostonMA02215 United States Brandeis University WalthamMA02453 United States Theory Group Weinberg Institute Department of Physics The University of Texas at Austin AustinTX78712 United States Department of Electrical and Computer Engineering Northeastern University BostonMA02115 United States Department of Physics The University of Texas at Austin AustinTX78712 United States Department of Physics Centre for Quantum Information and Quantum Control University of Toronto 60 Saint George St. TorontoONM5S 1A7 Canada Vector Institute MaRS Centre TorontoONM5G 1M1 Canada

In recent work, Akers et al. proved that the entanglement of purification Ep(A : B) is bounded below by half of the q-Rényi reflected entropy SR(q)(A : B) for all q ≥ 2, showing that Ep(A : B) = 1/2 SR(q)(A : B) for a class of random tensor network states. Naturally, the authors raise the question of whether a similar bound holds at q = 1. Our work answers that question in the negative by finding explicit counter-examples, which we arrive at through numerical optimization. Nevertheless, this result does not preclude the possibility that restricted sets of states, such as CFT states with semi-classical gravity duals, could obey the bound in question. Copyright © 2023, The Authors. All rights reserved.

关键词： Entropy

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