Johan Helsing

Sökresultat

• 2022

  An efficient full-wave solver for eddy currents

  Helsing, J., Karlsson, A. & Rosén, A., 2022 dec., I: Computers and Mathematics with Applications. 128, s. 145-162 18 s.

  Forskningsoutput: Tidskriftsbidrag › Artikel i vetenskaplig tidskrift › Peer review

  Öppen tillgång

  • Eddy Currents 100%
  • Eddy currents 74%
  • Reformulation 71%
  • Transmission Problem 56%
  • Superconducting materials 46%

• Solving Fredholm second-kind integral equations with singular right-hand sides on non-smooth boundaries

  Helsing, J. & Jiang, S., 2022 jan. 1, I: Journal of Computational Physics. 448, 110714.

  Forskningsoutput: Tidskriftsbidrag › Artikel i vetenskaplig tidskrift › Peer review

  • Boundary integral equations 100%
  • Steady flow 85%
  • Integral equations 78%
  • integral equations 66%
  • Integral Equations 57%
• 2021

  Comparison of integral equations for the Maxwell transmission problem with general permittivities

  Helsing, J., Karlsson, A. & Rosén, A., 2021 okt., I: Advances in Computational Mathematics. 47, 5, 76.

  Forskningsoutput: Tidskriftsbidrag › Artikel i vetenskaplig tidskrift › Peer review

  Öppen tillgång

  • Permittivity 100%
  • Transmission Problem 90%
  • Integral equations 80%
  • Integral Equations 58%
  • False 49%

• Dirac Integral Equations for Dielectric and Plasmonic Scattering

  Helsing, J. & Rosén, A., 2021 okt., I: Integral Equations and Operator Theory. 93, 5, 48.

  Forskningsoutput: Tidskriftsbidrag › Artikel i vetenskaplig tidskrift › Peer review

  Öppen tillgång

  • Plasmonics 100%
  • Dirac Equation 68%
  • Scattering 51%
  • Integral Equations 43%
  • Formulation 35%
• 2020

  An extended charge-current formulation of the electromagnetic transmission problem

  Helsing, J. & Karlsson, A., 2020 apr. 20, I: SIAM Journal on Applied Mathematics. 80, 2, s. 951-976 26 s.

  Forskningsoutput: Tidskriftsbidrag › Artikel i vetenskaplig tidskrift › Peer review

  • Boundary integral equations 100%
  • Maxwell equations 93%
  • Transmission Problem 88%
  • Electromagnetic waves 78%
  • Charge 74%
• 2019

  Physical-density integral equation methods for scattering from multi-dielectric cylinders

  Helsing, J. & Karlsson, A., 2019, I: Journal of Computational Physics. 387, s. 14-29 16 s.

  Forskningsoutput: Tidskriftsbidrag › Artikel i vetenskaplig tidskrift › Peer review

  • Integral Equation Method 100%
  • Integral equations 85%
  • Scattering 75%
  • integral equations 71%
  • Evaluation 58%
• 2018

  Corner effects on the perturbation of an electric potential

  Choi, D. S., Helsing, J. & Lim, M., 2018 jan. 1, I: SIAM Journal on Applied Mathematics. 78, 3, s. 1577-1601 25 s.

  Forskningsoutput: Tidskriftsbidrag › Artikel i vetenskaplig tidskrift › Peer review

  • Electric Potential 100%
  • Inclusion 62%
  • Polarization 59%
  • Perturbation 54%
  • Tensors 51%

• On a Helmholtz transmission problem in planar domains with corners

  Helsing, J. & Karlsson, A., 2018 okt. 15, I: Journal of Computational Physics. 371, s. 315-332 18 s.

  Forskningsoutput: Tidskriftsbidrag › Artikel i vetenskaplig tidskrift › Peer review

  • Transmission Problem 100%
  • Hermann Von Helmholtz 94%
  • Surface Plasmons 84%
  • Surface plasmons 67%
  • Permittivity 55%

• On integral equation methods for the first Dirichlet problem of the biharmonic and modified biharmonic equations in nonsmooth domains

  Helsing, J. & Jiang, S., 2018, I: SIAM Journal on Scientific Computing. 40, 4, s. A2609-A2630

  Forskningsoutput: Tidskriftsbidrag › Artikel i vetenskaplig tidskrift › Peer review

  • Nonsmooth Domains 100%
  • Integral Equation Method 95%
  • Biharmonic 90%
  • Biharmonic Equation 90%
  • Modified Equations 83%

• The spectra of harmonic layer potential operators on domains with rotationally symmetric conical points

  Helsing, J. & Perfekt, K. M., 2018, I: Journal des Mathematiques Pures et Appliquees. 118, s. 235-287

  Forskningsoutput: Tidskriftsbidrag › Artikel i vetenskaplig tidskrift › Peer review

  • Layer Potentials 100%
  • Potential Operators 95%
  • Harmonic 61%
  • Permittivity 48%
  • Tensors 48%
• 2017

  Classification of spectra of the Neumann–Poincaré operator on planar domains with corners by resonance

  Helsing, J., Kang, H. & Lim, M., 2017 juli 1, I: Annales de l'Institut Henri Poincare. Annales: Analyse Non Lineaire/Nonlinear Analysis. 34, 4, s. 991-1011 21 s.

  Forskningsoutput: Tidskriftsbidrag › Artikel i vetenskaplig tidskrift › Peer review

  • continuous spectra 100%
  • Continuous Spectrum 99%
  • operators 59%
  • Point Spectrum 49%
  • Operator 39%

• Resonances in Axially Symmetric Dielectric Objects

  Helsing, J. & Karlsson, A., 2017 juli 1, I: IEEE Transactions on Microwave Theory and Techniques. 65, 7, s. 2214-2227 14 s., 7857810.

  Forskningsoutput: Tidskriftsbidrag › Artikel i vetenskaplig tidskrift › Peer review

  • Integral equations 100%
  • Benchmarking 97%
  • integral equations 84%
  • Microwaves 82%
  • Wavelength 82%
• 2016

  Determination of normalized electric eigenfields in microwave cavities with sharp edges

  Helsing, J. & Karlsson, A., 2016, I: Journal of Computational Physics. 304, s. 465-486

  Forskningsoutput: Tidskriftsbidrag › Artikel i vetenskaplig tidskrift › Peer review

  Fil

  • Microwave 100%
  • Smooth surface 88%
  • Cavity 81%
  • Integral equations 80%
  • Magnetic Field 72%
  351 Nedladdningar (Pure)
• 2015

  Determination of normalized magnetic eigenfields in microwave cavities

  Helsing, J. & Karlsson, A., 2015, I: IEEE Transactions on Microwave Theory and Techniques. 63, 5, s. 1457-1467

  Forskningsoutput: Tidskriftsbidrag › Artikel i vetenskaplig tidskrift › Peer review

  Fil

  • Integral equations 100%
  • integral equations 84%
  • Microwaves 82%
  • Magnetic fields 82%
  • microwaves 63%
  377 Nedladdningar (Pure)

• Variants of an explicit kernel-split panel-based Nyström discretization scheme for Helmholtz boundary value problems

  Helsing, J. & Holst, A., 2015, I: Advances in Computational Mathematics. 41, 3, s. 691-708

  Forskningsoutput: Tidskriftsbidrag › Artikel i vetenskaplig tidskrift › Peer review

  Fil

  • Discretization Scheme 100%
  • Hermann Von Helmholtz 97%
  • Boundary value problems 95%
  • Integral equations 91%
  • Interpolation 72%
  207 Nedladdningar (Pure)
• 2014

  An explicit kernel-split panel-based Nyström scheme for integral equations on axially symmetric surfaces

  Helsing, J. & Karlsson, A., 2014, I: Journal of Computational Physics. 272, s. 686-703

  Forskningsoutput: Tidskriftsbidrag › Artikel i vetenskaplig tidskrift › Peer review

  Fil

  • Helmholtz equation 100%
  • Integral equations 72%
  • integral equations 61%
  • Integral Equations 52%
  • kernel 46%
  213 Nedladdningar (Pure)
• 2013

  A higher-order singularity subtraction technique for the discretization of singular integral operators on curved surfaces

  Helsing, J., 2013, Cornell University Library, 7 s. (arXiv; vol. http://arxiv.org/abs/1301.7276).

  Forskningsoutput: Working paper/Preprint › Working paper

  Fil
  53 Nedladdningar (Pure)

• An accurate boundary value problem solver applied to scattering from cylinders with corners

  Helsing, J. & Karlsson, A., 2013, I: IEEE Transactions on Antennas and Propagation. 61, 7, s. 3693-3700

  Forskningsoutput: Tidskriftsbidrag › Artikel i vetenskaplig tidskrift › Peer review

  Fil
  173 Nedladdningar (Pure)

• An accurate near-field solver for scattering from cylinders with corners

  Helsing, J. & Karlsson, A., 2013, [Host publication title missing]. IEEE - Institute of Electrical and Electronics Engineers Inc., s. 49-52 4 s.

  Forskningsoutput: Kapitel i bok/rapport/Conference proceeding › Konferenspaper i proceeding › Peer review

  Fil
  74 Nedladdningar (Pure)

• Approximate solution of boundary integral equations for biharmonic problems in non-smooth domains

  Didenko, V. & Helsing, J., 2013, Proceedings in Applied Mathematics and Mechanics. Cvetković, L., Atanacković, T. & Kostić, V. (red.). John Wiley & Sons Inc., Vol. 13. s. 435-438 4 s.

  Forskningsoutput: Kapitel i bok/rapport/Conference proceeding › Konferenspaper i proceeding › Peer review

  Fil

  • Biharmonic Problem 100%
  • Nonsmooth Domains 99%
  • Biharmonic Equation 89%
  • Stokes Flow 86%
  • Boundary Integral Equations 78%
  137 Nedladdningar (Pure)

• On the polarizability and capacitance of the cube

  Helsing, J. & Perfekt, K-M., 2013, I: Applied and Computational Harmonic Analysis. 34, 3, s. 445-468

  Forskningsoutput: Tidskriftsbidrag › Artikel i vetenskaplig tidskrift › Peer review

  Fil

  • Capacitance 100%
  • Permittivity 99%
  • Regular hexahedron 70%
  • Representing Measure 53%
  • Layer Potentials 51%
  138 Nedladdningar (Pure)

• On the Stability of the Nystrom Method for the Muskhelishvili Equation on Contours with Corners

  Didenko, V. D. & Helsing, J., 2013, I: SIAM Journal on Numerical Analysis. 51, 3, s. 1757-1776

  Forskningsoutput: Tidskriftsbidrag › Artikel i vetenskaplig tidskrift › Peer review

  Fil

  • Nyström Method 100%
  • Mathematical operators 66%
  • Angle 30%
  • Operator 25%
  • Algebra 25%
  189 Nedladdningar (Pure)

• Solving integral equations on piecewise smooth boundaries using the RCIP method: a tutorial

  Helsing, J., 2013, I: Abstract and Applied Analysis. 938167.

  Forskningsoutput: Tidskriftsbidrag › Artikel i vetenskaplig tidskrift › Peer review

  Öppen tillgång

  Fil

  • Integral equations 100%
  • Preconditioning 99%
  • Integral Equations 72%
  • Laplace equation 41%
  • Planar Curves 39%
  261 Nedladdningar (Pure)
• 2012

  An accurate boundary value problem solver applied to scattering from cylinders with corners

  Helsing, J. & Karlsson, A., 2012, [Publisher information missing]. 16 s. (Technical Report LUTEDX/(TEAT-7221)/1-16/(2012); vol. TEAT-7221)

  Forskningsoutput: Bok/rapport › Rapport › Forskning

  Fil

  • Boundary value problems 100%
  • Scattering 84%
  • Helmholtz equation 43%
  • Integral equations 31%
  • Electric fields 27%
  139 Nedladdningar (Pure)

• Resonances and Fields near Metamaterial Inclusions

  McPhedran, R., Helsing, J. & Milton, G., 2012, Antennas and Propagation Society International Symposium (APSURSI), 2012 IEEE. IEEE - Institute of Electrical and Electronics Engineers Inc., 2 s.

  Forskningsoutput: Kapitel i bok/rapport/Conference proceeding › Konferenspaper i proceeding › Peer review

  Öppen tillgång

  Fil

  • near fields 100%
  • inclusions 92%
  • permittivity 60%
  • divergence 25%
  144 Nedladdningar (Pure)
• 2011

  A Fast and Stable Solver for Singular Integral Equations on Piecewise Smooth Curves

  Helsing, J., 2011, I: SIAM Journal on Scientific Computing. 33, 1, s. 153-174

  Forskningsoutput: Tidskriftsbidrag › Artikel i vetenskaplig tidskrift › Peer review

  Fil

  • Integral equations 100%
  • Singular Integral Equation 96%
  • Crack 90%
  • Cracks 63%
  • Zigzag 61%
  212 Nedladdningar (Pure)

• Fast reconstruction of harmonic functions from Cauchy data using the Dirichlet-to-Neumann map and integral equations

  Helsing, J. & Johansson, B. T., 2011, I: Inverse Problems in Science and Engineering. 19, 5, s. 717-727

  Forskningsoutput: Tidskriftsbidrag › Artikel i vetenskaplig tidskrift › Peer review

  Fil

  • Harmonic functions 100%
  • Dirichlet-to-Neumann Map 87%
  • Integral equations 73%
  • Harmonic Functions 67%
  • Cauchy 60%
  149 Nedladdningar (Pure)

• Features of the Nyström method for the Sherman-Lauricella equation on Piecewise Smooth Contours

  Didenko, V. & Helsing, J., 2011, I: East Asian Journal on Applied Mathematics. 1, 4, s. 403-414

  Forskningsoutput: Tidskriftsbidrag › Artikel i vetenskaplig tidskrift › Peer review

  Fil

  • Mathematical operators 100%
  • Invertibility 88%
  • Algebra 56%
  • Pi 56%
  • Angle 45%
  153 Nedladdningar (Pure)

• Features of the Nyström Method for the Sherman-Lauricella Equation on Piecewise Smooth Contours

  Didenko, V. & Helsing, J., 2011, I: Book of Abstracts ESIAM 2011. s. 50-51

  Forskningsoutput: Tidskriftsbidrag › Publicerat konferensabstract › Peer review

• Spectral super-resolution in metamaterial composites

  Helsing, J., McPhedran, R. & Milton, G., 2011, I: New Journal of Physics. 13, 11

  Forskningsoutput: Tidskriftsbidrag › Artikel i vetenskaplig tidskrift › Peer review

  Öppen tillgång

  Fil

  • inclusions 100%
  • composite materials 77%
  • permittivity 29%
  • absorptance 26%
  • matrix materials 26%
  191 Nedladdningar (Pure)

• Stability of the Nyström Method for the Sherman–Lauricella Equation

  Didenko, V. & Helsing, J., 2011, I: SIAM Journal on Numerical Analysis. 49, 3, s. 1127-1148

  Forskningsoutput: Tidskriftsbidrag › Artikel i vetenskaplig tidskrift › Peer review

  Fil

  • Rhombus 100%
  • Experiments 99%
  • Unit circle 67%
  • Invertible 63%
  • Numerical Experiment 49%
  168 Nedladdningar (Pure)

• The effective conductivity of arrays of squares: Large random unit cells and extreme contrast ratios

  Helsing, J., 2011, I: Journal of Computational Physics. 230, 20, s. 7533-7547

  Forskningsoutput: Tidskriftsbidrag › Artikel i vetenskaplig tidskrift › Peer review

  Fil

  • Effective Conductivity 100%
  • Extremes 59%
  • Contrast media 54%
  • Cell 48%
  • Unit 45%
  155 Nedladdningar (Pure)

• The effective conductivity of random checkerboards

  Helsing, J., 2011, I: Journal of Computational Physics. 230, 4, s. 1171-1181

  Forskningsoutput: Tidskriftsbidrag › Artikel i vetenskaplig tidskrift › Peer review

  Fil

  • Effective Conductivity 100%
  • Ill-conditioning 86%
  • conditioning 73%
  • Integral equations 70%
  • Electrostatics 70%
  165 Nedladdningar (Pure)
• 2010

  Fast and stable reconstruction of harmonic functions from Cauchy data using integral equation techniques

  Helsing, J. & Johansson, B. T., 2010, s. 108-109.

  Forskningsoutput: Konferensbidrag › Konferensabstract › Peer review

• Fast reconstruction of harmonic functions from Cauchy data using integral equation techniques

  Helsing, J. & Johansson, B. T., 2010, I: Inverse Problems in Science and Engineering. 18, 3, s. 381-399

  Forskningsoutput: Tidskriftsbidrag › Artikel i vetenskaplig tidskrift › Peer review

  Öppen tillgång

  Fil

  • Harmonic functions 100%
  • Integral equations 73%
  • Harmonic Functions 67%
  • Cauchy 60%
  • Integral Equations 53%
  149 Nedladdningar (Pure)
• 2009

  Elastostatic computations on aggregates of grains with sharp interfaces, corners, and triple-junctions

  Helsing, J. & Ojala, R., 2009, I: International Journal of Solids and Structures. 46, 25-26, s. 4437-4450

  Forskningsoutput: Tidskriftsbidrag › Artikel i vetenskaplig tidskrift › Peer review

  Fil

  • elastostatics 100%
  • Multipole 94%
  • Elastostatics 81%
  • Elasticity 63%
  • Fast multipole Method 24%
  183 Nedladdningar (Pure)

• Faster convergence and higher accuracy for the Dirichlet-Neumann map

  Helsing, J., 2009, I: Journal of Computational Physics. 228, 7, s. 2578-2586

  Forskningsoutput: Tidskriftsbidrag › Artikel i vetenskaplig tidskrift › Peer review

  Fil

  • High Accuracy 100%
  • Dirichlet 86%
  • Laplace equation 64%
  • Mesh generation 59%
  • Integral equations 51%
  197 Nedladdningar (Pure)

• Integral equation methods for elliptic problems with boundary conditions of mixed type

  Helsing, J., 2009, I: Journal of Computational Physics. 228, 23, s. 8892-8907

  Forskningsoutput: Tidskriftsbidrag › Artikel i vetenskaplig tidskrift › Peer review

  Fil

  • Integral Equation Method 100%
  • Mixed Boundary Conditions 89%
  • Integral equations 85%
  • Elliptic Problems 72%
  • integral equations 71%
  320 Nedladdningar (Pure)
• 2008

  Corner singularities for elliptic problems: Integral equations, graded meshes, quadrature, and compressed inverse preconditioning

  Helsing, J. & Ojala, R., 2008, I: Journal of Computational Physics. 227, 20, s. 8820-8840

  Forskningsoutput: Tidskriftsbidrag › Artikel i vetenskaplig tidskrift › Peer review

  Öppen tillgång

  Fil

  • Corner Singularity 100%
  • Graded Meshes 99%
  • preconditioning 98%
  • Relative Error 78%
  • Conductivity 77%
  343 Nedladdningar (Pure)

• On the evaluation of layer potentials close to their sources

  Helsing, J. & Ojala, R., 2008, I: Journal of Computational Physics. 227, 5, s. 2899-2921

  Forskningsoutput: Tidskriftsbidrag › Artikel i vetenskaplig tidskrift › Peer review

  Öppen tillgång

  Fil

  • Layer Potentials 100%
  • quadratures 75%
  • Quadrature 71%
  • Interpolation 61%
  • Polynomials 56%
  343 Nedladdningar (Pure)
• 2006

  Approximate inverse preconditioners for some large dense random electrostatic interaction matrices

  Helsing, J., 2006, I: BIT Numerical Mathematics. 46, 2, s. 307-323

  Forskningsoutput: Tidskriftsbidrag › Artikel i vetenskaplig tidskrift › Peer review

  Fil

  • Coulomb interactions 100%
  • Approximate Inverse 84%
  • Electrostatics 73%
  • Preconditioner 60%
  • Interaction 45%
  151 Nedladdningar (Pure)
• 2005

  Laplace's equation and the Dirichlet-Neumann map: a new mode for Mikhlin's method

  Helsing, J. & Wadbro, E., 2005, I: Journal of Computational Physics. 202, 2, s. 391-410

  Forskningsoutput: Tidskriftsbidrag › Artikel i vetenskaplig tidskrift › Peer review

  Fil

  • Laplace equation 100%
  • Laplace's equation 76%
  • Dirichlet 66%
  • Computational complexity 60%
  • Exterior Domain 56%
  305 Nedladdningar (Pure)
• 2004

  A comparison of splittings and integral equation solvers for a nonseparable elliptic equation

  Englund, J. & Helsing, J., 2004, I: BIT Numerical Mathematics. 44, 4, s. 675-697

  Forskningsoutput: Tidskriftsbidrag › Artikel i vetenskaplig tidskrift › Peer review

  Fil

  • Nonseparable 100%
  • Integral equations 92%
  • Electrostatics 92%
  • Partial differential equations 85%
  • Elliptic Equations 77%
  166 Nedladdningar (Pure)

• A seventh-Order Accurate and Stable Algorithm for the Computation of Stress Inside Cracked Rectangular Domains

  Helsing, J. & Jonsson, A., 2004, I: International Journal for Multiscale Computational Engineering. 2, 1, s. 47-68

  Forskningsoutput: Tidskriftsbidrag › Artikel i vetenskaplig tidskrift › Peer review

  Öppen tillgång

  Fil

  • Stress Field 100%
  • Relative Error 94%
  • Integral equations 90%
  • Crack 82%
  • T-stress 72%
  146 Nedladdningar (Pure)
• 2003

  Stress computations on perforated polygonal domains

  Englund, J. & Helsing, J., 2003, I: Engineering Analysis with Boundary Elements. 27, 5, s. 533-546

  Forskningsoutput: Tidskriftsbidrag › Artikel i vetenskaplig tidskrift › Peer review

  Fil

  • Integral equations 100%
  • Integral Equation Method 58%
  • Trade-offs 47%
  • Fredholm Integral Equation 47%
  • Fast Algorithm 46%
  139 Nedladdningar (Pure)
• 2002

  On the accuracy of benchmark tables and graphical results in the applied mechanics literature

  Helsing, J. & Jonsson, A., 2002, I: Journal of Applied Mechanics. 69, 1, s. 88-90

  Forskningsoutput: Tidskriftsbidrag › Artikel i vetenskaplig tidskrift › Peer review

  Öppen tillgång

  Fil

  • computational mechanics 100%
  • elastic cylinders 94%
  • Computational mechanics 87%
  • error analysis 73%
  • fracture mechanics 73%
  139 Nedladdningar (Pure)

• On the computation of stress fields on polygonal domains with V-notches

  Helsing, J. & Jonsson, A., 2002, I: International Journal for Numerical Methods in Engineering. 53, 2, s. 433-453

  Forskningsoutput: Tidskriftsbidrag › Artikel i vetenskaplig tidskrift › Peer review

  Öppen tillgång

  Fil

  • V-notch 100%
  • Notch 79%
  • Stress Field 66%
  • Stress Intensity Factor 65%
  • Higher geometry 54%
  162 Nedladdningar (Pure)

• Stress calculations on multiply connected domains

  Helsing, J. & Jonsson, A., 2002, I: Journal of Computational Physics. 176, 2, s. 456-482

  Forskningsoutput: Tidskriftsbidrag › Artikel i vetenskaplig tidskrift › Peer review

  Fil

  • Multiply Connected Domain 100%
  • stress analysis 92%
  • Crack 74%
  • cracks 59%
  • Cracks 51%
  222 Nedladdningar (Pure)
• 2001

  Complex variable boundary integral equations for perforated infinite planes

  Helsing, J. & Jonsson, A., 2001, I: Engineering Analysis with Boundary Elements. 25, 3, s. 191-202

  Forskningsoutput: Tidskriftsbidrag › Artikel i vetenskaplig tidskrift › Peer review

  Öppen tillgång

  Fil

  • Boundary integral equations 100%
  • Complex Variables 77%
  • Boundary Integral Equations 77%
  • Integral equations 39%
  • Elasticity 34%
  106 Nedladdningar (Pure)

• Evaluation of the mode I stress intensity factor for a square crack in 3D

  Helsing, J., Jonsson, A. & Peters, G., 2001, I: Engineering Fracture Mechanics. 68, 5, s. 605-612

  Forskningsoutput: Tidskriftsbidrag › Letter › Peer review

  Öppen tillgång

  Fil

  • Fluorescence Maxima 100%
  • Stress intensity factors 75%
  • Cracks 51%
  • Integral equations 40%
  • Displacement 15%
  131 Nedladdningar (Pure)