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MODELING SOCCEr BY MEANS OF rELATIVE PHASE

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Journal of Systems Science & Complexity 2013年第1期26卷 14-20页

作者： SIEGLE malte LAMES Martin TU Munchen Department for Training and Computer Science in Sports

Soccer is a complex ***,appropriate(nontrivial) models have to be applied to be able to analyze the behavior of the teams on the *** study analyzed the World Cup Final 2006 between France and Italy by means of relative *** longitudinal and lateral positions of all 20 outfield players were used to calculate relative phase by Hilbert *** team-,group-,and attacker-fullbacks couplings showed that soccer is clearly an in-phase *** of the relative phase structure helped to identify scoring opportunities of the attacking ***,analyses of the relative phase structure can help to understand the complexity of soccer.

关键词： Perturbations relative phase soccer.

Importance of charge self-consistency in first-principles description of strongly correlated systems

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npj Computational Materials 2021年第1期7卷 1949-1956页

作者： Swagata Acharya Dimitar Pashov Alexander N.rudenk malte rösn.r Mark van Schilfgaarde Mikhail I.Katsnelson Institute for Molecules and Materials Radboud UniversityNijmegen 6525 AJThe Netherlands Theory and Simulation of Condensed Matter King's College LondonThe StrandLondon WC2R2LSUK National renewable Energy Laboratory Golden80401 ColoradoUSA

First-principles approaches have been successful in solving many-body Hamiltonians for real materials to an extent when correlations are weak or *** the electronic correlations become stronger often embedding methods based on first-principles approaches are used to better treat the correlations by solving a suitably chosen many-body Hamiltonian with a higher level *** success of such embedding theories,often referred to as second-principles,is commonly measured by the quality of self-energy E which is either a function of energy or momentum or ***,E should,in principle,also modify the electronic eigenfunctions and thus change the real space charge *** such practices are not prevalent,some works that use embedding techniques do take into account these *** such cases,choice of partitioning,of the parameters defining the correlated Hamiltonian,of double-counting corrections,and the adequacy of low-level Hamiltonian hosting the correlated subspace hinder a systematic and unambiguous understanding of such ***,for a large variety of correlated systems,strong correlations are largely confined to the charge *** an adequate non local low-order theory is important,and the high-order local correlations embedding contributes become *** we study the impact of charge self-consistency within two example cases,TiSez and CrBrs,and show how real space charge re-distribution due to correlation effects taken *** within a first-principles Green's function-based many-body perturbative approach is key in driving qualitative changes to the final electronic structure of these materials.

关键词： theory charge principles

Unveiling the inner structure of electron pulses generated from a laser-wakefield accelerator

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Light(Science & Applications) 2023年第10期12卷 1992-1994页

作者： malte C.Kaluza Institute of Optics and Quantum Electronics Max-Wien-Platz 107743JenaGermany Helmholtz-Institute Jena Fröbelstieg 307743JenaGermany

A novel diagnostic method has been used to gain deeper insight into the transverse structure and its evolution of electron pulses generated from a laser-wakefield accelerator.

关键词： structure field laser

LOCAL PrESSUrE COrrECTION FOr THE STOKES SYSTEM

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Journal of Computational Mathematics 2020年第1期38卷 125-141页

作者： malte Braack Utku Kaya Mathematical Seminar University of KielGermany

Pressure correction methods constitute the most widely used solvers for the timedependent Navier-Stokes *** are several different pressure correction methods,where each time step usually consists in a predictor step for a non-divergence-free velocity,followed by a Poisson problem for the pressure(or pressure update),and a final velocity correction to obtain a divergence-free vector *** some situations,the equations for the velocities are solved explicitly,so that the numerical most expensive step is the elliptic pressure *** here propose to solve this Poisson problem by a domain decomposition method which does not need any communication between the ***,this system is perfectly adapted for parallel *** show under certain assumptions that this new scheme has the same order of convergence as the original pressure correction scheme(with global projection).Numerical examples for the Stokes system show the effectivity of this new pressure correction *** convergence order O(k^2)for resulting velocity fields can be observed in the norm l^2(0,T;L^2(Ω)).

关键词： Stokes system Navier-Stokes Pressure correction Finite elements

rEVIEW ArTICLE FINITE ELEMENTS WITH LOCAL PrOJECTION STABILIZATION FOr INCOMPrESSIBLE FLOW PrOBLEMS

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Journal of Computational Mathematics 2009年第2期27卷 116-147页

作者： malte Braack Gerr Lube Mathematisches Seminar Christian-Albrechts-Universitt zu KielLudewig-Meyn-Str.4D-24098 KielGermany Institut für Numerische und Angewandte Mathematik Georg-August Universitt GttingenLotzestrasse 16-18 D-37083 GttingenGermany

In this paper we review recent developments in the analysis of finite element methods for incompressible flow problems with local projection stabilization （LPS）. These methods preserve the favourable stability and approximation properties of classical residual-based stabilization （rBS） techniques but avoid the strong coupling of velocity and pressure in the stabilization terms. LPS-methods belong to the class of symmetric stabilization techniques and may be characterized as variational multiscale methods. In this work we summarize the most important a priori estimates of this class of stabilization schemes developed in the past 6 years. We consider the Stokes equations, the Oseen linearization and the NavierStokes equations. Furthermore, we apply it to optimal control problems with linear（ized） flow problems, since the symmetry of the stabilization leads to the nice feature that the operations ＂discretize＂ and ＂optimize＂ commute.

关键词： Finite element method Stabilization Computational fluid dynamics Errorestimates Navier-Stokes Stokes

Coexisting charge density wave and ferromagnetic instabilities in monolayer InSe

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npj Computational Materials 2022年第1期8卷 1101-1109页

作者： Evgeny A.Stepanov Viktor Harkov malte rösn.r Alexander I.Lichtenstein Mikhail I.Katsnelson Alexander N.rudenko CPHT CNRSEcole PolytechniqueInstitut Polytechnique de ParisF-91128PalaiseauFrance I.Institute of Theoretical Physics University of HamburgNotkestraße 922607HamburgGermany European X-ray Free-Electron Laser Facility Holzkoppel 422869SchenefeldGermany radboud University Institute for Molecules and Materials6525AJNijmegenThe Netherlands The Hamburg Centre for Ultrafast Imaging Luruper Chaussee 14922761HamburgGermany

recently fabricated InSe monolayers exhibit remarkable characteristics that indicate the potential of this material to host a number of many-body *** this work,we systematically describe collective electronic effects in hole-doped InSe monolayers using advanced many-body *** this end,we derive a realistic electronic-structure model from first principles that takes into account the most important characteristics of this material,including a flat band with prominent van Hove singularities in the electronic spectrum,strong electron–phonon coupling,and weakly screened long-ranged Coulomb *** calculate the temperature-dependent phase diagram as a function of band filling and observe that this system is in a regime with coexisting charge density wave and ferromagnetic instabilities that are driven by strong electronic Coulomb *** regime can be achieved at realistic doping levels and high enough temperatures,and can be verified *** find that the electron–phonon interaction does not play a crucial role in these effects,effectively suppressing the local Coulomb interaction without changing the qualitative physical picture.

关键词： ferromagnetic charge wave

Deformable microlaser force sensing

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Light(Science & Applications) 2024年第6期13卷 1196-1209页

作者： Eleni Dalaka Joseph SHill Jonathan H.H.Booth Anna Popczyk Stefan r.Pulver malte C.Gather Marcel Schubert Centre of Biophotonics SUPASchool of Physics and AstronomyUniversity of St AndrewsNorth HaughSt AndrewsUK Humboldt Centre for Nano-and Biophotonics Department of ChemistryUniversity of CologneKölnGermany School of Psychology and Neuroscience University of St AndrewsSt Mary’s QuadSouth StreetSt AndrewsUK Institute for Bioengineering of Catalonia BarcelonaSpain

Mechanical forces are key regulators of cellular behavior and function,affecting many fundamental biological processes such as cell migration,embryogenesis,immunological responses,and pathological *** force sensors and imaging techniques have been developed to quantify these otherwise invisible forces in single cells and in ***,current techniques rely heavily on high-resolution microscopy and do not allow interrogation of optically dense tissue,reducing their application to 2D cell cultures and highly transparent biological ***,we introduce DEFOrM,deformable microlaser force sensing,a spectroscopic technique that detects sub-nanonewton forces with unprecedented spatio-temporal *** is based on the spectral analysis of laser emission from dye-doped oil microdroplets and uses the force-induced lifting of laser mode degeneracy in these droplets to detect nanometer *** validation by atomic force microscopy and development of a model that links changes in laser spectrum to applied force,DEFOrM is used to measure forces in 3D and at depths of hundreds of microns within tumor spheroids and late-stage Drosophila *** furthermore show continuous force sensing with single-cell spatial and millisecond temporal resolution,thus paving the way for non-invasive studies of biomechanical forces in advanced stages of embryogenesis,tissue remodeling,and tumor invasion.

关键词： invasion otherwise hundreds

Common microscopic origin of the phase transitions in Ta_(2)NiS_(5) and the excitonic insulator candidate Ta_(2)NiSe_(5)

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npj Computational Materials 2021年第1期7卷 1919-1932页

作者： Lukas Windgätter malte rösn.r Giacomo Mazza Hannes Hübener Antoine Georges Andrew J.Millis Simone Latini Angel rubio Max Planck Institute for the Structure and Dynamics of Matter Luruper Chaussee 14922761 HamburgGemany radboud University Institute for Molecules and MaterialsHeijendaalseweg 1356525 AJ NijmegenNetherlands Department of Quantum Matter Physics University of GenevaQuai Ernest-Ansermet 241211 GenevaSwitzerland College de France 11 place Marcelin Berthelot75005 ParisFrance Center for Computational Quantum Physics Flatiron InstituteNew YorkNY 10010USA.CPHTCNRSEcole PolytechniqueIP Paris91128 PalaiseauFrance Department of Physics Columbia UniversityNew YorkNY 10027USA.Nano-Bio Spectroscopy Group Departamento de Fisica de Materiales Universidad del Pais Vasco20018 San SebastianSpain

The structural phase transition in Ta-NiSes has been envisioned as driven by the formation of an excitonic insulating ***,the role of structural and electronic instabilities on crystal symmetry breaking has yet to be ***,the phase transition in its complementary material Ta_(2)NiS_(5)does not show any experimental hints of an excitonic insulating *** present a microscopic investigation of the electronic and phononic effects involved in the structural phase transition in Ta_(2)NiSe_(5)and Ta-Niss using extensive first-principles *** both materials the crystal symmetries are broken by phonon instabilities,which in tum lead to changes in the electronic bandstructure also observed in the experiment.A total energy landscape analysis shows no tendency towards a purely electronic instability and we find that a sizeable lattice distortion is needed to open a *** conclude that an excitonic instability is not needed to explain the phase transition in both Ta_(2)NiSe_(5)and Ta_(2)NiS_(5).

关键词： phase structural transitions

DIrECTIONAL DO-NOTHING CONDITION FOr THE NAVIEr-STOKES EQUATIONS

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Journal of Computational Mathematics 2014年第5期32卷 507-521页

作者： malte Braack Piotr Boguslaw Mucha Mathematisches Seminar Christian-Albrechts-Universitat zu Kiel Ludewig-Meyn-Str. 4 D-24098 Kiel Germany Institute of Applied Mathematics and Mechanics University of Warsaw ul Banacha 2 02-097 Warszawa Poland

The numerical solution of flow problems usually requires bounded domains although the physical problem may take place in an unbounded or substantially larger domain. In this case, artificial boundaries are necessary. A well established artificial boundary condition for the Navier-Stokes equations diseretized by finite elements is the “do-nothing” condition. The reason for this is the fact that this condition appears automatically in the variational formulation after partial integration of the viscous term and the pressure gradient. This condition is one of the most established outflow conditions for Navier-Stokes but there are very few analytical insight into this boundary condition. We address the question of existence and stability of weak solutions for the Navier-Stokes equations with a “directional do-nothing” condition. In contrast to the usual “do-nothing” condition this boundary condition has enhanced stability properties. In the case of pure outflow, the condition is equivalent to the original one, whereas in the case of inflow a dissipative effect appears. We show existence of weak solutions and illustrate the effect of this boundary condition by computation of steady and non-steady flows.

关键词： Boundary conditions Navier-Stokes Outflow condition Existence.