Fiche individuelle
Zuqi TANG  
Titre  Maître de conférences  
Equipe  Outils et Méthodes Numériques  
Adresse  Université Lille 1 Batiment P2 59655 VILLENEUVED'ASCQ  
Téléphone  +33 (0)320434280  
zuqi.tang@univlille.fr  
Site personnel  https://orcid.org/0000000254025858  
Réseau scientifique  https://www.researchgate.net/profile/Zuqi_Tang  
Publications 
ACLI Revue internationale avec comité de lecture 

[1] Adaptive inexact iterative algorithms based on polynomialdegreerobust a posteriori estimates for the Stokes problem Numer. Math. (2018) 138: 1027, Vol. 138, N°. 4, pages. 1027–1065, 03/2018, URL, Abstract ČERMÁK Martin, HECHT Frédéric, TANG Zuqi, VOHRALÍK Martin 
In this paper, we develop adaptive inexact versions of iterative algorithms applied to finite element discretizations of the linear Stokes problem. We base our developments on an equilibrated stress a posteriori error estimate distinguishing the different error components, namely the discretization error component, the (inner) algebraic solver error component, and possibly the outer algebraic solver error component for algorithms of the Uzawa type. We prove that our estimate gives a guaranteed upper bound on the total error, as well as a polynomialdegreerobust local efficiency, and this on each step of the employed iterative algorithm. Our adaptive algorithms stop the iterations when the corresponding error components do not have a significant influence on the total error. The developed framework covers all standard conforming and conforming stabilized finite element methods on simplicial and rectangular parallelepipeds meshes in two or three space dimensions and an arbitrary algebraic solver. Implementation into the FreeFem++ programming language is invoked and numerical examples showcase the performance of our a posteriori estimates and of the proposed adaptive strategies. As example, we choose here the unpreconditioned and preconditioned Uzawa algorithm and the preconditioned minimum residual (MinRes) algorithm, in combination with the Taylor–Hood discretization. 
[2] Modeling of MagneticInduced Deformation Using Computer Code Chaining and SourceTensor Projection IEEE Transactions on Magnetics, Vol. 53, N°. 6, pages. 14, 02/2017, URL, Abstract LIU Mingyong, TANG Zuqi, MININGER Xavier, BOUILLAULT Frédéric, HUBERT Olivier, BERNARD Laurent 
Source tensor projections are developed for the magnetoelastic coupled problems when magnetostrictioninduced force and magnetic force are considered. Comparisons with classical force density projection are first performed on a simple example. Then, it is investigated on an application of a multilayer transformer core with the consideration of material anisotropy and multilayer inhomogeneity. 
[3] Residual a posteriori error estimation for a stochastic magnetostatic problem Journal of Computational and Applied Mathematics, Vol. 289, pages. 5167, 12/2015, URL, Abstract MAC Duy Hung, TANG Zuqi, CLENET Stéphane, CREUSE Emmanuel 
In this paper, we propose an a posteriori error estimator for the numerical approximation of a stochastic magnetostatic problem, whose solution depends on the spatial variable but also on a stochastic one. The spatial discretization is performed with finite elements and the stochastic one with a polynomial chaos expansion. As a consequence, the numerical error results from these two levels of discretization. In this paper, we propose an error estimator that takes into account these two sources of error, and which is evaluated from the residuals. 
[4] Residualbased a posteriori estimators for the potential formulations of electrostatic and timeharmonic eddy current problems with voltage or current excitation International Journal for Numerical Methods in Engineering, Vol. 107, N°. 5, pages. 377394, 12/2015, URL, Abstract CHEN Chao, CREUSE Emmanuel, NICAISE Serge, TANG Zuqi 
In this paper, we consider some potential formulations of electrostatic as well as timeharmonic eddy current problems with voltage or current excitation sources. The wellposedness of each formulation is first established. Then, the reliability of the corresponding residualbased a posteriori estimators is derived in the context of the finite element method approximation. Finally, the implementation in an industrial code is performed, and the obtained theoretical results are illustrated on an academic and on an industrial benchmark. 
[5] A posteriori residual error estimators with mixed boundary conditions for quasistatic electromagnetic problem The International Journal for Computation and Mathematics in Electrical and Electronic Engineering (COMPEL), Vol. 34, N°. 3, pages. 724739, 07/2015, URL TANG Zuqi, LE MENACH Yvonnick, CREUSE Emmanuel, NICAISE Serge, PIRIOU Francis, NEMITZ Nicolas 
[6] Residual a posteriori estimator for magnetoharmonic potential formulations with global quantities for the source terms IEEE Transactions on Magnetics, Vol. 51, N°. 3, 06/2015, Abstract TANG Zuqi, LE MENACH Yvonnick, CREUSE Emmanuel, NICAISE Serge, PIRIOU Francis 
In the modeling of eddy current problems, potential formulations are widely used in recent days. In this paper, the results of residualbased a posteriori error estimators, which evaluate the discretization error in the finiteelement computation, are extended to the case of several kinds of source terms for both A/φ and T/Ω harmonic formulations. The definitions of the estimators are given and some numerical examples are provided to show the behavior of the estimators. 
[7] Finite element mesh adaptation strategies from residual and hierarchical error estimators in eddy current problems IEEE Transactions on Magnetics, Vol. 51, N°. 3, 04/2015, URL, Abstract DULAR Patrick, LE MENACH Yvonnick, TANG Zuqi, CREUSE Emmanuel, PIRIOU Francis 
A strategy of mesh adaptation in eddy current finite element modeling is developed from both residual and hierarchical error estimators. Wished distributions of element sizes of adapted meshes are determined from the elementwise local contributions to the estimators and define constraints for the mesh generator. Uniform distributions of the local error are searched. 
[8] Energetic Galerkin Projection of Electromagnetic Fields Between Different Meshes IEEE Transactions on Magnetics, Vol. 50, N°. 2, pages. 613616, 02/2014, URL, Abstract WANG Zifu, TANG Zuqi, HENNERON Thomas, PIRIOU Francis, MIPO JeanClaude 
Meshtomesh field transfer arises frequently in finite element computations. Typical applications may concern remeshing, multigrid methods, domain decomposition and multiphysics problems. For electromagnetic fields, one of the essential constraints in such transfers is to conserve energetic quantities such as the magnetic energy and the joule heating. Within the framework of Galerkin projection on overlapping domains, we introduce the definition of energetic norms for electromagnetic fields. The corresponding formulations we propose, provide energyconserving projection of electromagnetic fields between different meshes.

[9] Comparison of Residual and Hierarchical Finite Element Error Estimators in Eddy Current Problems IEEE Transactions on Magnetics, Vol. 50, N°. 2, pages. 501504, 02/2014, URL, Abstract DULAR Patrick, TANG Zuqi, LE MENACH Yvonnick, CREUSE Emmanuel, PIRIOU Francis 
The finite element computation of eddy current problems introduces numerical error. This error can only be estimated. Among all error estimators (EEs) already developed, two estimators, called residual and hierarchical EEs, proven to be reliable and efficient, are theoretically and numerically compared. Both estimators show similar behaviors and locations of the error. 
[10] Helmholtz decomposition of vector fields with mixed boundary conditions and an application to a posteriori finite element error analysis of the Maxwell system Mathematical Methods in the Applied Sciences, Vol. 38, N°. 4, pages. 738750, 02/2014, URL, Abstract CREUSE Emmanuel, NICAISE Serge, TANG Zuqi 
This paper is devoted to the derivation of a Helmholtz decomposition of vector fields in the case ofmixed boundary conditions imposed on the boundary of the domain. This particular decomposition allows to obtain a residual a posteriori error estimator for the approximation ofmagnetostatic problems given in the socalled Aformulation, for which the reliability can be established. Numerical tests confirm the obtained theoretical predictions. 
[11] Residual and equilibrated error estimators for magnetostatic problems solved by finite element method IEEE Transactions on Magnetics, Vol. 49, N°. 12, pages. 5715  5723, 12/2013, URL, Abstract TANG Zuqi, LE MENACH Yvonnick, CREUSE Emmanuel, NICAISE Serge, PIRIOU Francis 
In finite element computations, the choice of the mesh is crucial to obtain accurate solutions. In order to evaluate the quality of the mesh, a posteriori error estimators can be used. In this paper, we develop residualbased error estimators for magnetostatic problems with both classical formulations in term of potentials used, as well as the equilibrated error estimator. We compare their behaviors on some numerical applications, to understand the interest of each of them in the remeshing process. 
[12] A posteriori error estimator for harmonic APhi formulation The international journal for computation and mathematics in electrical and electronic engineering, Vol. 32, N°. 4, pages. 1219  1229, 07/2013, URL TANG Zuqi, LE MENACH Yvonnick, CREUSE Emmanuel, NICAISE Serge, PIRIOU Francis 
[13] Residual based a posteriori error estimators for harmonic A/Phi and T/Omega formulations in eddy current problems IEEE Transactions on Magnetics, Vol. 49, N°. 5, 05/2013, URL TANG Zuqi, LE MENACH Yvonnick, CREUSE Emmanuel, NICAISE Serge, PIRIOU Francis 
[14] Residualbased a posteriori estimators for the T/Omega magnetodynamic harmonic formulation of the Maxwell system International Journal of Numerical Analysis and Modeling, Vol. 10, N°. 2, pages. 411429, 02/2013, URL, Abstract CREUSE Emmanuel, NICAISE Serge, TANG Zuqi, LE MENACH Yvonnick, NEMITZ Nicolas, PIRIOU Francis 
In this paper, we focus on an a posteriori residualbased error estimator for the T/Omega
magnetodynamic harmonic formulation of the Maxwell system. Similarly to the A/Phi formulation, the weak continuous and discrete formulations are established, and the wellposedness of
both of them is addressed. Some useful analytical tools are derived. Among them, an adhoc
Helmholtz decomposition for the T/Omega
case is derived, which allows to pertinently split the error.
Consequently, an a posteriori error estimator is obtained, which is proven to be reliable and locally
efficient. Finally, numerical tests confirm the theoretical results. 
[15] Residualbased a posteriori estimators for the A/Phi magnetodynamic harmonic formulation of the Maxwell system Mathematical Models and Methods in Applied Sciences, Vol. 22, N°. 5, pages. 30, 05/2012, URL, Abstract CREUSE Emmanuel, NICAISE Serge, TANG Zuqi, LE MENACH Yvonnick, NEMITZ Nicolas, PIRIOU Francis 
This paper is devoted to the derivation of an a posteriori residualbased error estimator for the APhi magnetodynamic harmonic formulation of the Maxwell system. The weak continuous and discrete formulations are established, and the wellposedness of both of them is addressed. Some useful analytical tools are derived. Among them, an ad hoc Helmholtz decomposition is proven, which allows to pertinently split the error. Consequently, an a posteriori error estimator is obtained, which is proven to be reliable and locally efficient. Finally, numerical tests confirm the theoretical results. 
ACT Conférence internationale avec acte 
[1] 3D coupled electromagneticfluidthermal analysis and experiment of 10kV oilimmersed triangular wound core transformer 2019 Joint MMMIntermag, January 1418, 2019 Washington, DC, 01/2019 GONG Ruohan, TANG Zuqi, WANG Shuhong, HENNERON Thomas, RUAN Jiangjun 
[2] An Improved Newton Method Based on choosing Initial Guess Applied to Scalar Potential Formulation in Nonlinear Magnetostatics CEFC 2018, Hangzhou, China, 10/2018 CHERIF Riheb, TANG Zuqi, GUYOMARC’H Frédéric, CHEVALLIER Loïc, LE MENACH Yvonnick 
[3] Calibration of a Miniature Single Sheet Tester with Guaranteed FEsimulation CEFC 2018, Hangzhou, China, 10/2018 TANG Zuqi, ZHAO Yanpu, BENABOU Abdelkader 
[4] Application of UNet Network and Training Strategy to Optimal Mesh Refinement in Computational Electromagnetism CEFC 2018, Hangzhou, China, 10/2018 TANG Zuqi, SHEN Xi, HENNERON Thomas 
[5] An improved starting point for Newton’s method solving 3D nonlinear magnetostatic problems EPNC 2018, Arras, France, 06/2018 CHERIF Riheb, TANG Zuqi, GUYOMARC’H Frédéric, CHEVALLIER Loïc, LE MENACH Yvonnick 
[6] Gauged Dual Formlations for Fast and Accurate Computation of Inductance Parameters of Magnetostatics Problems EMF 2018, Darmstadt, Germany, 04/2018 ZHAO Yanpu, TANG Zuqi 
[7] Dual Regularized Formulations for Open Boundary Magnetostatic Problems EMF 2018, Darmstadt, Germany, 04/2018 ZHAO Yanpu, TANG Zuqi 
[8] 3D modeling of magnetoelastic behavior using simplified multiscale model: Application on power transformer core COMPUMAG 2017, Daejeon, Korea, 06/2017 TANG Zuqi, LIU Mingyong, BOUILLAULT Frédéric, MININGER Xavier, HUBERT Olivier 
[9] Vibration Prediction of NonOriented Silicon Iron Power Transformer Core under DC Bias COMPUMAG 2017, Daejeon, Korea, 06/2017 LIU Mingyong, HUBERT Olivier, TANG Zuqi, BOUILLAULT Frédéric, MININGER Xavier, BERNARD Laurent 
[10] Adaptive Stopping Criteria for Iterative Solver Applied to Potential Formulations in Magnetostatic Problems COMPUMAG 2017, Daejeon, Korea, 06/2017 TANG Zuqi 
[11] A posteriori error estimators for A and Ω magnetostatic formulations based on equilibrated fluxes reconstructions COMPUMAG 2017, Daejeon, Korea, 06/2017 TANG Zuqi 
[12] Error estimation in the computation of induced currents of human body 2013 CIGRE SCC3 & EMFELF Colloquium, Japan, 10/2013 LELONG Thomas, TANG Zuqi, SCORRETTI Riccardo, THOMAS Pierre, LE MENACH Yvonnick, CREUSE Emmanuel 
[13] Energetic Galerkin projection of electromagnetic fields between different meshes
COMPUMAG 2013 Budapest, Hungary, 07/2013, Abstract WANG Zifu, TANG Zuqi, HENNERON Thomas, PIRIOU Francis, MIPO JeanClaude 
The Galerkin projection provides an useful tool to transfer electromagnetic fields between different meshes.
Given an electromagnetic field calculated on the source mesh, the transfer to a different mesh can be employed for modelcoupling, domain decomposition, remeshing, visualization and similar proposes.
The Galerkin projection consists of calculating a target field which minimizes the interpolation error between two discretized fields.
However, the $L^2$ Galerkin projection suffers from nonconservation of the electromagnetic energy.
In this paper, we present an energetic approach for Galerkin projections. 
[14] Comparison of Residual and Hierarchical Finite Element Error
Estimators in Eddy Current Problems COMPUMAG 2013 Budapest, Hungary, 07/2013, URL, Abstract TANG Zuqi, DULAR Patrick, LE MENACH Yvonnick, CREUSE Emmanuel, PIRIOU Francis 
The finite element computation of eddy current
problems gives numerical error. This error cannot be calculated,
but can only be estimated. Among all error estimators already
developed, it is proposed to compare two proven estimators
called residual and hierarchical error estimators. 
[15] Error estimation in the Computation of Induced Current of Human Body in the Case of Low frequency Magnetic Field Excitation COMPUMAG 2013 Budapest, Hungary, 07/2013 LELONG Thomas, TANG Zuqi, SCORRETTI Riccardo, THOMAS Pierre, LE MENACH Yvonnick, CREUSE Emmanuel 
[16] Residual based a posteriori error estimator for harmonic APhi and TOmega formulation in eddy current problems CEFC 2012 Oita, Japan, 11/2012, Abstract TANG Zuqi, LE MENACH Yvonnick, CREUSE Emmanuel, NICAISE Serge, PIRIOU Francis 
For the eddy current problem, the potential formulations are widely used today. In this communication, residual based a posteriori error estimators are introduced to evaluate the discretization error in the finite element calculation in both case of APhi and TOmega harmonic formulations. An example is carried out to show the behavior of our estimators. 
[17] A posteriori error estimator for harmonic APhi formulation EPNC 2012 Pula, Croatia, 06/2012, Abstract TANG Zuqi, LE MENACH Yvonnick, CREUSE Emmanuel, NICAISE Serge, PIRIOU Francis 
In this paper a residualbased error estimator is proposed to evaluate the numerical error induced by the computation of the electromagnetic systems using a Finite Element Method in the case of the harmonic APhi formulation. This estimator is based on the evaluation of quantities weakly verified by the formulation. Furthermore as this estimator verifies the notions of reliability and efficiency it allows to estimate the qualities of local and global solutions. Two examples of electromagnetic systems with current density induced are used to show the efficiency of the proposed estimator. 
[18] A TIMEDOMAIN IMPLICITSCHEMA DIRECT SOLVER: APPLICATION TO FINITE INTEGRATION SOLUTION
ISEF 2011, 09/2011, Abstract WANG Zifu, LE MENACH Yvonnick, TANG Zuqi, KORECKI Julien, HENNERON Thomas 
In timedomain electromagnetic fields computation, numerical methods (such as Finite Element
Method (FEM), Finite Integration Technique (FIT) [13] and etc.) have been applied. For the time
domain integration solution, explicit and implicit schemas have been widely used.
In comparison with implicit methods, the explicit methods are easier to realize in terms of
computation complexity, however, they are constrained by the stability condition. This condition
may require a small time step and therefore a prohibitive computing time. Another possibility is to
use an implicit schema which ensures the numerical stability. Unfortunately the implicit methods
require equation solved at each time step [4]. As a consequence, despite of a free choice on time
step, the computation time using the full implicit methods increases.
In this paper, fixedpoint explicit calculation is introduced to an implicit schema. This method
combines the two advantages of implicit and explicit methods: no stability condition and no
equation solving. The solver is then applied to a timedomain eddy current problem. Using
orthogonal mesh cells and FIT, the massmatrices in discrete formulations are diagonal. The fixed
point explicit method allows direct calculations without matrix inversion or decomposition.

[19] Comparison of Residual and Equilibrated Error Estimators for FEM Applied to Magnetostatic Problems COMPUMAG 2011 Sydney, Australie, 07/2011, Abstract TANG Zuqi, LE MENACH Yvonnick, CREUSE Emmanuel, NICAISE Serge, PIRIOU Francis 
In finite element computations, the choice of the mesh is crucial to obtain an accurate solution. In order to evaluate
the quality of the mesh, a posteriori error estimators can be used. In this paper, we analyze and compare the residual and equilibrated error estimators for magnetostatic problems. 
ACN Conférence nationale avec acte 
[1] Estimateurs d’erreur a posteriori pour les équations de la magnétodynamique en formulation potentielle (A/φ) harmonique Journées du GDR Calcul 2011 Paris, 07/2011 TANG Zuqi 
INV Conférence invité 
[1] Residualbased Error Estimator for Finite Element Method Applied to Quasi Static fields monag, Curitiba, 09/2014 LE MENACH Yvonnick, TANG Zuqi, TITTARELLI Roberta 
TH Thèse 
[1] Estimateurs d’erreur a posteriori résiduels en éléments finis pour la résolution de problèmes d'électromagnétisme en formulations potentielles Université Lille 1, 11/2012 TANG Zuqi 