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Smoothing Control of Discrete Linear Repetitive Processes

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Smoothing Control of Discrete Linear Repetitive Processes

Iterative Learning Control Applied to a Deformable Mirror

2011 Chinese Control and Decision Conference（CCDC）

作者： blazej cichy Krzysztof Galkowski Eric Rogers Anton Kummert Institute of Control and Computation Engineering University of Zielona Góra currently a Gerhard Mercator guest professor at University of Wuppertal School of Electronics and Computer Science University of Southampton Faculty of Electrical Information and Media EngineeringUniversity of Wuppertal

Repetitive processes are a distinct class of twodimensional （2D） systems （*** propagation in two independent directions occurs） of both systems theoretic and applications *** particular,a repetitive process makes a series of sweeps or passes through dynamics defined on a finite *** the end of each pass,the process returns to the starting point and the next pass *** novel feature is that the output on the previous pass acts as a forcing function on,and hence contributes to,the current pass *** has been a considerable volume of profitable work on the development of a control theory for such processes but currently the most effective control law design algorithms are based on sufficient but not necessary stability conditions and hence conservativeness may prevent the design of control laws in some *** paper considers the design of a new control law which exploits extra available information to allow stabilizing control law design.

关键词： Linear Repetitive Processes Stability analysis Control law design

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Iterative Learning Control Applied to a Deformable Mirror

High-accuracy thermodynamic properties to the melting point from ab initio calculations aided by machine-learning potentials

第36届中国控制会议

作者： blazej cichy Petr Augusta Krzysztof Galkowski Eric Rogers Institute of Control and Computation Engineering University of Zielona Góra Institute of Information Theory and Automation The Czech Academy of Sciences Department of Electronics and Computer Science University of Southampton

An unconditionally stable finite difference discretization motivated by the well-known Crank-Nicolson method is used to develop an iterative learning control design for systems whose dynamics are described by a fourth-order partial differential equation.A discrete in time and space model of a deformable rectangular mirror is derived in this setting and forms the basi s for the new design,where a model for the actuator dynamics is also included.A numerical case study is given to demonstrate the properties of the new design.

关键词： Crank-Nicolson Discretization Method Iterative Learning Control Thin Plates

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npj Computational Materials 2023年第1期9卷 2310-2321页

作者： Jong Hyun Jung Prashanth Srinivasan Axel Forslund blazej Grabowski Institute for Materials Science University of StuttgartPfaffenwaldring 5570569 StuttgartGermany

Accurate prediction of thermodynamic properties requires an extremely accurate representation of the free-energy *** are twofold—first,the inclusion of the relevant finite-temperature mechanisms,and second,a dense volume–temperature grid on which the calculations are performed.A systematic workflow for such calculations requires computational efficiency and reliability,and has not been available within an ab initio framework so ***,we elucidate such a framework involving direct upsampling,thermodynamic integration and machine-learning potentials,allowing us to incorporate,in particular,the full effect of anharmonic *** improved methodology has a five-times speed-up compared to state-of-the-art *** calculate equilibrium thermodynamic properties up to the melting point for bcc Nb,magnetic fcc Ni,fcc Al,and hcp Mg,and find remarkable agreement with experimental data.A strong impact of anharmonicity is observed specifically for *** introduced procedure paves the way for the development of ab initio thermodynamic databases.

关键词： harmonic point prediction

Each coin has 2 sides: a positive role of alien Potamopyrgus antipodarum (Grey, 1843) snails in reducing the infection of native lymnaeids with trematodes

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Current Zoology 2024年第2期70卷 262-269页

作者： Anna cichy Anna Stanicka Elzbieta Zbikowska Faculty of Biological and Veterinary Sciences Nicolaus Copernicus University in TorunLwowska 187-100 TorunPoland

The change in the distribution of organisms in freshwater ecosystems due to natural or manmade processes raises the question of the impact of alien species on local *** most studies indicate a negative effect,the positive one is more difficult to discern,espe-cially in multispecies systems,including hosts and *** purpose of the study was to check whether the presence of an alien host,Potamopyrgus antipodarum,reduces the intensity of Echinoparyphium aconiatum metacercariae in a native host,Radix *** additionally tested the impact of water temperature and the biomass of the alien host on the dilution *** experimentally studied(1)the lifespan of echinostome cercariae in different temperatures,(2)the infectivity of cercariae toward the alien host and native host,and(3)the impact of different biomass of the alien host on the intensity of metacercariae in the native *** found that cercarial survival and infectivity were tem-perature ***,cercarial survival decreased with increasing temperature,contrary to cercarial *** cercariae entered the renal cavity of both the native host and alien host,and successfully transformed into *** number of metacercariae in the native host decreased with the increasing biomass of the alien *** results indicate that lymnaeids may benefit from the co-occur-rence with P antipodarum,as the presence of additional hosts of different origins may reduce the prevalence of parasites in native ***,the scale of the dilution effect depends not only on the increased spectrum of susceptible hosts but also on the other variables of the environment,including water temperature and host density.

关键词： biological invasion density dilution effect echinostomes Radix spp. temperature.

Magnetic Moment Tensor Potentials for collinear spin-polarized materials reproduce different magnetic states of bcc Fe

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npj Computational Materials 2022年第1期8卷 107-112页

作者： Ivan Novikov blazej Grabowski Fritz Körmann Alexander Shapeev Skolkovo Institute of Science and Technology Skolkovo Innovation CenterNobel St.3Moscow143026Russia Institute for Materials Science University of StuttgartPfaffenwaldring 5570569StuttgartGermany Computational Materials Design Max-Planck-Institut für Eisenforschung GmbHD-40237DüsseldorfGermany Materials Science and Engineering Delft University of Technology2628 CDDelftThe Netherlands

We present the magnetic Moment Tensor Potentials(mMTPs),a class of machine-learning interatomic potentials,accurately reproducing both vibrational and magnetic degrees of freedom as provided,e.g.,from first-principles *** accuracy is achieved by a two-step minimization scheme that coarse-grains the atomic and the spin *** performance of the mMTPs is demonstrated for the prototype magnetic system bcc iron,with applications to phonon calculations for different magnetic states,and molecular-dynamics simulations with fluctuating magnetic moments.

关键词： magnetic fluctuating states

A machine learning approach to model solute grain boundary segregation

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npj Computational Materials 2018年第1期4卷 130-137页

作者： Liam Huber Raheleh Hadian blazej Grabowski Jörg Neugebauer Max-Planck-Institut für Eisenforschung GmbH D-40237 DüsseldorfGermany

Even minute amounts of one solute atom per one million bulk atoms may give rise to qualitative changes in the mechanical response and fracture resistance of modern structural *** changes are commonly related to enrichment by several orders of magnitude of the solutes at structural defects in the host *** underlying concept—segregation—is thus fundamental in materials *** include it in modern strategies of materials design,accurate and realistic computational modelling tools are ***,the enormous number of defect configurations as well as sites solutes can occupy requires models which rely on severe *** the present study we combine a high-throughput study containing more than 1 million data points with machine learning to derive a computationally highly efficient framework which opens the opportunity to model this important mechanism on a routine basis.

关键词： grain solute boundary

Glycerol steam reforming over calcium hydroxyapatite supported cobalt and cobalt-cerium catalysts

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Journal of Energy Chemistry 2018年第2期27卷 404-412页

作者： J.Dobosz M.cichy M.Zawadzki T.Borowiecki Institute of Low Temperature and Structure Research Department of Nanomaterials Chemistry and Catalysis Polish Academy of Sciences PO Box 1410 50-950 Wroclaw Poland Maria Curie-Sklodowska University Faculty of Chemistry Department of Chemical Technology 3 Maria Curie-Sklodowska Square 20-031 Lublin Poland

Calcium hydroxyapatite（HAp） supported cobalt and cobalt-cerium catalysts were examined for hydrogen production in glycerol steam reforming. The catalysts were synthesized by incipient wetness impregnation method and characterized through X-ray diffraction, adsorption-desorption isotherms of N2 and temperature-programmed reduction of H2. Catalytic properties were examined in terms of glycerol conversion, selectivity toward hydrogen and C-containing products in temperature range of 650-800 ℃.The effect of active metal reduction and residence time（thereby flow feed rate） was analysed. It was found that the growth of residence time increased the hydrogen selectivity in the whole temperatures range whereas the catalyst reduction, before the catalytic process, decreased the hydrogen selectivity at temperatures lower than 750 ℃. The cerium addition improved the catalytic behaviour for hydrogen production via glycerol steam reforming. Cerium oxide suppressed the sintering of cobalt particles and as a result Co-Ce/HAp ensured higher stability and H2 selectivity than Co/HAp. Under reaction conditions investigated in this study, the highest selectivity toward hydrogen at 650 ℃ was obtained for 7.5 Co-Ce/HAp catalyst.

关键词： Calcium hydroxyapatite Cobalt catalysts Cobalt-cerium catalysts Glycerol steam reforming

A Raman laser system for multi-wavelength satellite laser ranging

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Science China(Physics,Mechanics & Astronomy) 2004年第6期47卷 737-743页

作者： K.Hamal I.Prochazka J.blazej Czech Technical University in Prague CzechCzech Technical University in PragueCzechCzech Technical University in PragueCzech

In order to develop a laser system for multi-wavelength satellite laser ranging, the joint group of the Shanghai Astronomical Observatory and the Czech Technical University has studied the conversion efficiency of the Raman-shifting beam and its spatial characteristics. We adopted a 0.53 μm laser with pulse width of 35 ps and peak energy of 35 mJ, the second harmonic of a Nd:YAG actively and passively mode-locked laser, to pump a one-meter-long Raman tube which is full of H2 with high pressure at the Prague-based laboratory. We get the first Stokes laser (0.68 μm): 7 mJ (single pulse) with beam divergence of 40″ (arcsecond) and spatial wobbling of less than 4″; and the first anti-Stokes laser (0.43 μm): 2 mJ (single pulse) with divergence of 56″ and spatial wobbling of less than 4″. The emitting beam from the Raman cell also includes 0.53 μm: 10 mJ (single pulse) with divergence of 40″ and spatial wobbling of less than 7″. According to the radar link equation and based on the above obtained multi-wavelength’s energy, we can estimate the detection probabilities for three colors respectively. It is shown by the result that the developed multi-wavelength Raman laser system has the capability of satellite ranging. The Raman laser system will be installed at the laser station in Shanghai Astronomical Observatory to research the multi-wavelength satellite laser ranging.

关键词： multi-wavelength satellite laser ranging, Raman laser, atmosphere correction, detection probability.

Chemically induced local lattice distortions versus structural phase transformations in compositionally complex alloys

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npj Computational Materials 2021年第1期7卷 312-319页

作者： Yuji Ikeda Konstantin Gubaev Jörg Neugebauer blazej Grabowski Fritz Körmann Institute for Materials Science University of StuttgartStuttgartGermany Max-Planck-Institut für Eisenforschung GmbH DüsseldorfGermany Department of Materials Science and Engineering Delft University of TechnologyDelftThe Netherlands

Recent experiments show that the chemical composition of body-centered cubic(bcc)refractory high entropy alloys(HEAs)can be tuned to enable transformation-induced plasticity(TRIP),which significantly improves the ductility of these *** calls for an accurate and efficient method to map the structural stability as a function of composition.A key challenge for atomistic simulations is to separate the structural transformation between the bcc and theωphases from the intrinsic local lattice distortions in such chemically disordered *** solve this issue,we develop a method that utilizes a symmetry analysis to detect differences in the crystal *** this method in combination with ab initio calculations,we demonstrate that local lattice distortions largely affect the phase stability of Ti–Zr–Hf–Ta and Ti–Zr–Nb–Hf–Ta *** relaxation effects are properly taken into account,the predicted compositions near the bcc–hcp energetic equilibrium are close to the experimental compositions,for which good strength and ductility due to the TRIP effect are observed.

关键词： alloys ductility distortion