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arXiv 2019年

作者： Park, Shinkyu Martins, Nuno C. Shamma, Jeff S. Department of Mechanical and Aerospace Engineering Princeton University PrincetonNJ08544 United States Department of Electrical and Computer Engineering and the Institute for Systems Research University of Maryland College ParkMD20742 United States Thuwal23955-6900 Saudi Arabia

We consider that at every instant each member of a population, which we refer to as an agent, selects one strategy out of a finite set. The agents are nondescript, and their strategy choices are described by the so-called population state vector, whose entries are the portions of the population selecting each strategy. Likewise, each entry of the so-called payoff vector is the reward attributed to a strategy. We consider that a finite-dimensional nonlinear dynamical system, denoted as payoff dynamics model (PDM), specifies a mechanism that determines the payoff as a causal map of the population state. A boundedrationality protocol, which is often inspired on evolutionary biology principles, governs how each agent continually revises its strategy based on complete or partial knowledge of the population state and payoff. The population is protocol-homogeneous but is otherwise strategy-heterogeneous considering that the agents are allowed to select distinct strategies concurrently. A stochastic mechanism determines the instants when agents revise their strategies, but we consider that the population is large enough that, with high probability, the population state can be approximated with arbitrary accuracy uniformly over any finite horizon by a so-called (deterministic) mean population state. We propose an approach that takes advantage of passivity principles to obtain sufficient conditions determining, for a given protocol and PDM, when the mean population state is guaranteed to converge to a meaningful set of equilibria, which could be either an appropriately defined extension of Nash-s for the PDM or a perturbed version of it. By generalizing and unifying previous work, our framework also provides a foundation for future work. We specialize our results for well-known protocols and a class of PDM that includes as particular cases the payoff mechanisms proposed in previous work to model learning, inertia, and anticipation. Copyright © 2019, The Authors. All rights re

关键词： Stochastic systems

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Unraveling Ultrafast Photoionization in Hexagonal Boron Nitride

arXiv

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arXiv 2021年

作者： Xue, Lianjie Liu, Song Hang, Yang Summers, Adam M. Wilson, Derrek J. Wang, Xinya Chen, Pingping Folland, Thomas G. Hachtel, Jordan A. Shi, Hongyu Hosseini-Zavareh, Sajed Das, Suprem R. Lei, Shuting Zhang, Zhuhua Sorensen, Christopher M. Guo, Wanlin Caldwell, Joshua D. Edgar, James H. Blaga, Cosmin I. Trallero-Herrero, Carlos A. Department of Physics Kansas State University ManhattanKS66506 United States Tim Taylor Department of Chemical Engineering Kansas State University ManhattanKS66506 United States J. R. Macdonald Laboratory Department of Physics Kansas State University ManhattanKS66506 United States State Key Laboratory of Mechanics and Control of Mechanical Structures Institute of Nano Science Nanjing University of Aeronautics and Astronautics Nanjing210016 China Advanced Laser Light Source and few-cycle Inc. Institut Nationale de la Recherche Scientifique 1650 Boul. Lionel-Boulet VarennesQCJ3X 1P7 Canada Department of Industrial and Manufacturing Systems Engineering Kansas State University ManhattanKS66506 United States Department of Mechanical Engineering Vanderbilt University NashvilleTN37212 United States Center for Nanophase Materials Science Oak Ridge National Laboratory Oak Ridge37830 United States Department of Electrical and Computer Engineering Kansas State University ManhattanKS66506 United States Department of Physics University of Connecticut StorrsCT06269 United States

The non-linear response of dielectrics to intense, ultrashort electric fields has been a sustained topic of interest for decades with one of its most important applications being femtosecond laser micro/nano-machining. More recently, renewed interests in strong field physics of solids were raised with the advent of mid-infrared femtosecond laser pulses, such as high-order harmonic generation, optical-field-induced currents, etc. All these processes are underpinned by photoionization (PI), namely the electron transfer from the valence to the conduction bands, on a time scale too short for phononic motion to be of relevance. Here, in hexagonal boron nitride, we reveal that the bandgap can be finely manipulated by femtosecond laser pulses as a function of field polarization direction with respect to the lattice, in addition to the field’s intensity. It is the modification of bandgap that enables the ultrafast PI processes to take place in dielectrics. We further demonstrate the validity of the Keldysh theory in describing PI in dielectrics in the few TW/cm2 regime. © 2021, CC BY.

关键词： Photoionization

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Simultaneous state and parameter estimation: The role of sensitivity analysis

arXiv

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arXiv 2020年

作者： Liu, Jianbang Gnanasekar, Aristarchus Zhang, Yi Bo, Song Liu, Jinfeng Hu, Jingtao Zou, Tao Key Laboratory of Networked Control Systems Shenyang Institute of Automation Chinese Academy of Sciences Shenyang110016 China Institute for Robotics & Intelligent Manufacturing Chinese Academy of Sciences Shenyang110016 China University of Chinese Academy of Sciences Beijing100049 China Department of Chemical & Materials Engineering University of Alberta EdmontonABT6G 1H9 Canada Key Laboratory of Energy Thermal Conversion & Control Southeast University Nanjing210096 China School of Mechanical and Electrical Engineering Guangzhou University Guangzhou510006 China

State and parameter estimation is essential for process monitoring and control. Observability plays an important role in both state and parameter estimation. In simultaneous state and parameter estimation, the parameters are often augmented as extra states of the original system. When the augmented system is observable, various existing state estimation approaches may be used to estimate the states and parameters simultaneously. However, when the augmented system is not observable, how we should proceed to maximally extract the information contained in the measured outputs is not clear. This paper concerns about simultaneous state and parameter estimation when the augmented system is not fully observable. Specifically, we first show how sensitivity analysis is related to observability of a dynamical system, and then illustrate how it may be used to select variables for simultaneous estimation. We also propose a moving horizon state estimation (MHE) design that can use the variable selection results in a natural way. Extensive simulations are carried out to show the efficiency of the proposed approach. Copyright © 2020, The Authors. All rights reserved.

关键词： Sensitivity analysis

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Decentralized controller design in flexure-linked gantry by H2 guaranteed cost optimization approach 18

Decentralized controller design in flexure-linked gantry by ...

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18th International Conference of the European Society for Precision engineering and Nanotechnology, EUSPEN 2018

作者： Ma, Jun Chen, Si-Lu Liang, Wenyu Teo, Chek Sing Tay, Arthur Al Mamun, Abdullah Tan, Kok Kiong SIMTech-NUS Joint Lab. on Precision Motion Systems Department of Electrical and Computer Engineering National University of Singapore Singapore117582 Singapore Department of Electrical and Computer Engineering National University of Singapore Singapore117583 Singapore Agency for Science Technology and Research Singapore Institute of Manufacturing Technology Singapore138634 Singapore Zhejiang Provincial Key Laboratory of Robotics and Intelligent Manufacturing Equipment Technology Ningbo Institute of Industrial Technology Chinese Academy of Sciences Ningbo Zhejiang315201 China

ISBN: (纸本)9780995775121

Dual-drive H-gantry is widely used in many industrial processes that require high-speed and high-precision Cartesian motion. Unlike the rigid-linked gantry design, the flexure-linked design is able to prevent the damage of the cross-arm because a small degree of rotation angle is possible. However, the flexure-linked design may induce the resonant modes of the gantry because of high frequency control signals. To maintain the precision tracking of two carriages and minimize the chattering of control efforts, we aim to seek the most suitable flexure joints among the available ones while optimizing the decentralized feedback controller parameters under model uncertainties. In this way, good tracking performance is achieved without costly system re-design. In this work, we formulate the mechatronic design problem as an H2 guaranteed cost control problem. All the stabilizing feedback controller gains are parameterized over a convex set, and the global optimum is obtained by means of an outer-linearization-based algorithm. Experiments are conducted and the results successfully validate the effectiveness of the proposed design approach. © 2018 CURRAN-CONFERENCE. All rights reserved.

关键词： Convex optimization Dual-drive H-gantry Flexure Mechatronic design Optimal control Parallel mechanism

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Development of a Tetris playing robot controlled by KNR 15

Development of a Tetris playing robot controlled by KNR

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15th IEEE International Conference on Mechatronics and Automation, ICMA 2018

作者： Wang, Ming Zhang, Yanlu Dong, Huifang Li, Xu Yu, Junzhi Department of Information and Electrical Engineering University of Shandong Jianzhu University Jinan250100 China Department of Intelligent Robotics State Key Laboratory of Management and Control for Complex Systems Institute of Automation Chinese Academy of Sciences Beijing100190 China

ISBN: (纸本)9781538660720

Robot plays an increasingly important role in daily life. This paper presents a vision-based wheeled robot for playing Tetris. How to control the robot is elaborated at length in this paper. The robot adopted a KNR controller as its core controller. With a CCD sensor, it identified colored blocks, lines and the destination. All algorithms are programed with LabVIEW. The experiments and the contest validated the effectiveness of the proposed vision-based wheeled robot system. © 2018 IEEE.

关键词： Controllers

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Memristor-enhanced humanoid robot control system – Part II: Circuit theoretic model and performance analysis

Memristor-enhanced humanoid robot control system – Part II:...

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作者： Baumann, D. Ascoli, A. Tetzlaff, R. Chua, L.O. Hild, M. Institute of Circuits and Systems Faculty of Electrical and Computer Engineering Technische Universität Dresden Dresden Germany Autonomous Motion Department Max Planck Institute for Intelligent Systems Tübingen Germany Department of Electrical Engineering and Computer Sciences University of California Berkeley BerkeleyCA United States Fachbereich VII Forschungslabor Neurorobotik Beuth Hochschule für Technik Berlin Berlin Germany

Neuromorphic circuits shall be considered in electronics to perform complex computing tasks in a time-efficient and energy-efficient fashion and to adapt their problem-solving methodologies to changes in initial conditions and parameters. One of the key biological paradigms at the basis of their operation, allowing them to exhibit higher performance levels as compared with state-of-the-art electronic systems, is the mem-computing functionality, i.e. the capability to process and store data in the same physical location, which represents the core principle to overcome the time inefficiency of von Neumann machine architectures. With the advent of memristors, the interest in the exploitation of this principle to develop dynamic circuits for the implementation of innovative signal processing strategies has grown considerably. Here, we leverage the mem-computing capability inherent in these devices to propose an innovative control system for motion control in a humanoid robot. In the part I paper, we introduced the paradigm theoretic foundations. In this part II manuscript, we propose circuit-theoretic models for the new control system based upon an ideal and upon a physical memristor model and demonstrate through numerical simulations how it outperforms the old approach in terms of time-efficiency and energy-efficiency, maintaining a good degree of adaptability to changes in environmental conditions. Copyright © 2017 John Wiley & Sons, Ltd.

关键词： Timing circuits

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Semi-Parametric Kernel-Based Identification of Wiener systems 57

Semi-Parametric Kernel-Based Identification of Wiener System...

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57th IEEE Conference on Decision and Control, CDC 2018

作者： Sven Risuleo, Riccardo Lindsten, Fredrik Hjalmarsson, Hakan Department of Automatic Control School of Electrical Engineering and Computer Science KTH - Royal Institute of Technology Stockholm Sweden Department of Information Technology Division of Systems and Control Uppsala University Uppsala Sweden

ISBN: (纸本)9781538613955

We present a technique for kernel-based identification of Wiener systems. We model the impulse response of the linear block with a Gaussian process. The static nonlinearity is modeled with a combination of basis functions. The coefficients of the static nonlinearity are estimated, together with the hyperparameters of the covariance function of the Gaussian process model, using an iterative algorithm based on the expectation-maximization method combined with elliptical slice sampling to sample from the posterior distribution of the impulse response given the data. The same sampling method is then used to find the posterior-mean estimate of the impulse response. We test the proposed algorithm on a benchmark of randomly-generated Wiener systems. © 2018 IEEE.

关键词： Impulse response

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Effect of Non-Uniformity of Electric Field on Breakdown Strength of Cryogenic Gaseous Insulation Media for Superconducting Power Applications

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IOP Conference Series: Materials Science and engineering 2020年第1期756卷

作者： S. Telikapalli M. Kvitkovicova P. Cheetham C. Park C.H. Kim L. Graber S. Pamidi FAMU-FSU College of Engineering Department of Electrical & Computer Engineering Tallahassee FL 32310 USA Center for Advanced Power Systems Florida State University Tallahassee FL 32310 USA Georgia Institute of Technology College of Engineering Department of Electrical & Computer Engineering Atlanta GA 30332 USA

A new experimental set up for measuring the breakdown strength of gas media in weakly non-uniform electric field at cryogenic temperatures and high pressures is described. Measure of breakdown strength of helium gas at 77 K and 293 K in a non-uniform electric field with a field efficiency factor 62.5% are presented. The results suggest that the breakdown strength in weakly non-uniform electric field relate to that of uniform electric field by the field efficiency factor, η. This relationship holds good for both 293 K and 77 K data. This observation expands our previously reported systematics of dielectric strength in uniform electric field to the weakly non-uniform electric field conditions, which is important for designing HTS power applications. The established relationship eliminates the need for costly experiments for measuring the dielectric strength at a specific operating temperature and pressure and in the required non-uniformity of the electric field.

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Memristor-enhanced humanoid robot control system – Part I: Theory behind the novel memcomputing paradigm

Memristor-enhanced humanoid robot control system – Part I: ...

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作者： Ascoli, A. Baumann, D. Tetzlaff, R. Chua, L.O. Hild, M. Institute of Circuits and Systems Faculty of Electrical and Computer Engineering Technische Universität Dresden Dresden Germany Autonomous Motion Department Max Planck Institute for Intelligent Systems Tübingen‡ Germany Department of Electrical Engineering and Computer Sciences University of California Berkeley BerkeleyCA United States Fachbereich VII Forschungslabor Neurorobotik Beuth Hochschule für Technik Berlin Berlin Germany

Myon is a humanoid robot where each joint is controlled independently by a supervised bio-inspired artificial neural network inducing the correction of a number of distinct actions depending on the excitation. One of the control strategies, which the network, located within a certain joint, may implement, allows a controlled motion of the limb connected to the joint from a stable state up to a prescribed height and the maintenance of the new position afterwards. The original approach adopted for this control operation is stable and robust but results in slow and energy-inefficient limb movements. This work proposes a novel, low-power, time-efficient and adaptive memristor-centred control strategy for the aforementioned robot action. The idea is based upon the exploitation of the combined ability of memristors to store and process data in the same physical location. The part I paper sets the theoretic foundations for the memcomputing paradigm to robot motion control, while the part II manuscript shall demonstrate its benefits over the original approach in terms of energy, and speed, and the inheritance from the standard strategy of a good level of adaptability to changes in the limb load on the basis of the analysis of circuit-theoretic models adopting an ideal and a real memristor, respectively. Copyright © 2017 John Wiley & Sons, Ltd. Copyright © 2017 John Wiley & Sons, Ltd.

关键词： Timing circuits

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Stochastic dc optimal power flow with reserve saturation

arXiv

引用

arXiv 2019年

作者： Kannan, Rohit Luedtke, James R. Roald, Line A. Wisconsin Institute for Discovery University of Wisconsin-Madison MadisonWI United States Department of Industrial and Systems Engineering Wisconsin Institute for Discovery University of Wisconsin-Madison MadisonWI United States Department of Electrical and Computer Engineering University of Wisconsin-Madison MadisonWI United States

We propose an optimization framework for stochastic optimal power flow with uncertain loads and renewable generator capacity. Our model follows previous work in assuming that generator outputs respond to load imbalances according to an affine control policy, but introduces a model of saturation of generator reserves by assuming that when a generator's target level hits its limit, it abandons the affine policy and produces at that limit. This is a particularly interesting feature in models where wind power plants, which have uncertain upper generation limits, are scheduled to provide reserves to balance load fluctuations. The resulting model is a nonsmooth nonconvex two-stage stochastic program, and we use a stochastic approximation method to find stationary solutions to a smooth approximation. Computational results on 6-bus and 118-bus test instances demonstrates that by considering the effects of saturation, our model can yield solutions with lower expected generation costs (at the same target line violation probability level) than those obtained from a model that enforces the affine policy to stay within generator limits with high probability. Copyright © 2019, The Authors. All rights reserved.

关键词： Stochastic programming

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