Dr Stephen Langdon


Email address: s.langdon@reading.ac.uk

Telephone: +44 (0)118 378 5021


Recent and ongoing research projects


Recent and upcoming meetings


Publications

    Book chapter

  1. S.N. Chandler-Wilde and S. Langdon. Acoustic scattering: high frequency boundary element methods and unified transform methods, in Unified Transform for Boundary Value Problems: Applications and Advances (Fokas, Pelloni, eds.), 181-226, SIAM, Philadelphia, PA, 2015. [arxiv: 1410.6137]
  2. Journal Publications

  3. J. A. Hargreaves, Y. W. Lam and S. Langdon. A transformation approach for efficient evaluation of oscillatory surface integrals arising in three-dimensional boundary element methods, Int. J. Numer. Methods Engrg, 108(2), 93-115, 2016.
  4. T. E. Lee, M. J. Baines and S. Langdon. A finite difference moving mesh method based on conservation for moving boundary problems, J. Comput. Appl. Math., 288, 1-17, 2015.
  5. D. P. Hewett, S. Langdon and S. N. Chandler-Wilde. A frequency-independent boundary element method for scattering by two-dimensional screens and apertures, IMA J. Numer. Anal., 35(4), 1698-1728, 2015. [arxiv: 1401.2786]
  6. S. N. Chandler-Wilde, D. P. Hewett, S. Langdon and A. Twigger. A High Frequency Boundary Element Method for Scattering by a Class of Nonconvex Obstacles, Numer. Math., 129(4), 647-689, 2015. [arxiv: 1401.2817]
  7. S. G. Groth, D. P. Hewett and S. Langdon. Hybrid numerical-asymptotic approximation for high frequency scattering by penetrable convex polygons, IMA J. Appl. Math., 80(2), 324-353, 2015.
  8. T. E. Lee, M. J. Baines, S. Langdon and M. J. Tindall. A moving mesh approach for modelling avascular tumour growth. Appl. Numer. Math., 72, 99-114, 2013.
  9. S. Langdon, D. J. Needham, B. A. Samson and J. P. Gilchrist. The unsteady flow of a weakly compressible fluid in a thin porous layer. III: Three-dimensional computations. Quart. J. Mech. Appl. Math. 66(1), 123-155, 2013.
  10. D. J. Needham, S. Langdon, B. A. Samson and J. P. Gilchrist. The unsteady flow of a weakly compressible fluid in a thin porous layer. II: Three-dimensional theory. Quart. J. Mech. Appl. Math. 66(1), 97-122, 2013.
  11. D. P. Hewett, S. Langdon and J. M. Melenk. A high frequency hp boundary element method for scattering by convex polygons. SIAM J. Numer. Anal., 51(1), 629-653, 2013.
  12. S. N. Chandler-Wilde, I. G. Graham, S. Langdon and E. A. Spence. Numerical-asymptotic boundary integral methods in high frequency acoustic scattering. Acta Numer., 21, 89-305, 2012.
  13. S. N. Chandler-Wilde, S. Langdon and M. Mokgolele. A high frequency boundary element method for scattering by convex polygons with impedance boundary conditions. Commun. Comput. Phys., 11(2), 573-593, 2012.
  14. T. Betcke, S. N. Chandler-Wilde, I. G. Graham, S. Langdon and M. Lindner. Condition number estimates for combined potential integral operators in acoustics and their boundary element discretisation. Numer. Methods Partial Differential Equations, 27(1), 31-69, 2011. [arxiv: 1007.3074]
  15. S. Langdon, M. Mokgolele and S. N. Chandler-Wilde. High frequency scattering by convex curvilinear polygons. J. Comput. Appl. Math., 234, 2020-2026, (2010), doi: 10.1016/j.cam.2009.08.053.
  16. S. N. Chandler-Wilde, I. G. Graham, S. Langdon and M. Lindner. Condition number estimates for combined potential boundary integral operators in acoustic scattering. J. Integral Equations Appl., 21, 229-279, 2009.
  17. D. J. Needham, S. Langdon, G. S. Busswell and J. P. Gilchrist. The unsteady flow of a weakly compressible fluid in a thin porous layer. I: Two-dimensional theory. SIAM J. Appl. Math., 69, 1084-1109, 2009.
  18. J. F. Blowey, J. R. King and S. Langdon. Small- and waiting-time behaviour of the thin-film-equation. SIAM J. Appl. Math., 67, 1776-1807, 2007.
  19. S. N. Chandler-Wilde and S. Langdon. A Galerkin boundary element method for high frequency scattering by convex polygons. SIAM J. Numer. Anal., 45, 610-640, 2007.
  20. M. Ganesh, S. Langdon and I. H. Sloan. Efficient evaluation of highly oscillatory acoustic scattering surface integrals. J. Comput. Appl. Math., 204, 363-374, 2007.
  21. S. Arden, S. N. Chandler-Wilde and S. Langdon. A collocation method for high frequency scattering by convex polygons. J. Comput. Appl. Math., 204, 334-343, 2007.
  22. S. Langdon and S. N. Chandler-Wilde. A wavenumber independent boundary element method for an acoustic scattering problem. SIAM J. Numer. Anal., 43, 2450-2477, 2006.
  23. S. N. Chandler-Wilde, S. Langdon and L. Ritter. A high wavenumber boundary element method for an acoustic scattering problem. Philos. Trans. A, 362, 647-671, 2004.
  24. J. W. Barrett, S. Langdon and R. Nurnberg. Finite element approximation of a sixth order nonlinear degenerate parabolic equation. Numer. Math., 96, 401-434, 2004.
  25. S. Langdon and I. G. Graham. Boundary integral methods for singularly perturbed boundary value problems. IMA J. Numer. Anal. 21, 217-237, 2001
  26. Refereed Conference Proceedings

  27. J. A. Hargreaves, Y. W. Lam, S. Langdon, D. P. Hewett. A high-frequency BEM for 3D acoustic scattering, Proceedings of the 22nd International Congress on Sound and Vibration, Florence, Italy, July 2015.
  28. A. Gibbs S. N. Chandler-Wilde, S. Langdon and A. Moiola. Hybrid numerical asymptotic approximation for multiple scattering problems, Proceedings of Waves 2015, Karlsruhe, Germany, July 2015.
  29. S. P. Groth, D. P. Hewett and S. Langdon. A high-frequency boundary element method for a transmission scattering problem, Proceedings of Waves 2015, Karlsruhe, Germany, July 2015.
  30. J. A. Hargreaves, D. P. Hewett, Y. W. Lam, S. Langdon. A high-frequency boundary element method for scattering by three-dimensional screens, Proceedings of Waves 2015, Karlsruhe, Germany, July 2015.
  31. C. Howarth, S. N. Chandler-Wilde, S. Langdon and P. Childs. Enriching a Hankel basis by ray tracing in the ultra weak variational formulation. Proceedings of Waves 2013, Gammarth, Tunisia, pp. 349-350.
  32. S. G. Groth, D. P. Hewett and S. Langdon. Hybrid numerical-asymptotic approximation of high frequency scattering by penetrable convex polygons. Proceedings of Waves 2013, Gammarth, Tunisia, pp. 327-328.
  33. S. N. Chandler-Wilde, D. P. Hewett, S. Langdon and A. Twigger. A high frequency hp-boundary element method for scattering by two-dimensional screens. Proceedings of Waves 2013, Gammarth, Tunisia, pp. 321-322.
  34. S. N. Chandler-Wilde, D. P. Hewett, S. Langdon and A. Twigger. A high frequency BEM for scattering by non-convex obstacles. Proc. 10th International Conference on Mathematical and Numerical Aspects of Wave Propagation, pp.307-310, 2011.
  35. S. Langdon and S. N. Chandler-Wilde. Boundary element methods for high frequency scattering problems. Mathematisches Forschungsinstitut Oberwolfach, Report No. 10/2010, DOI: 10.4171/OWR/2010/10, pp. 60-63, 2010.
  36. S. N. Chandler-Wilde, S. Langdon and A. Twigger. High frequency boundary element methods for scattering by non-convex obstacles: a model problem, pages 86-87, Proceedings of Waves 2009, the 9th International Conference on Mathematical and Numerical Aspects of Wave Propagation, 15-19 June 2009, Pau, France.
  37. M. Mokgolele, S. Langdon and S. N. Chandler-Wilde. High frequency scattering by a convex polygon with impedance boundary condition, pages 280-281, Proceedings of Waves 2009, the 9th International Conference on Mathematical and Numerical Aspects of Wave Propagation, 15-19 June 2009, Pau, France.
  38. S. N. Chandler-Wilde, S. Langdon and M. Mokgolele. Numerical methods for high frequency acoustic scattering problems. Proceedings of the Institute of Acoustics, Vol.30, pt 2, 2008.
  39. M. Mokgolele, S. N. Chandler-Wilde and S. Langdon. High frequency scattering by convex curvilinear polygons. Proc. 8th Int. Conf. on Mathematical and Numerical Aspects of Wave Propagation, Reading University, pages 96-98, 2007.
  40. J. M. Melenk and S. Langdon. An hp-boundary element method for high frequency scattering by convex polygons. Proc. 8th Int. Conf. on Mathematical and Numerical Aspects of Wave Propagation, Reading University, pages 93-95, 2007.
  41. S. Langdon, D. Huybrechs and S. N. Chandler-Wilde. A fully discrete collocation method for high frequency scattering by convex polygons. Proc. 8th Int. Conf. on Mathematical and Numerical Aspects of Wave Propagation, Reading University, pages 84-86, 2007.
  42. S. N. Chandler-Wilde, I. G. Graham, S. Langdon and M. Lindner. Condition Number Estimates for Combined Potential Integral Operators in Acoustic Scattering. Proc. 8th Int. Conf. on Mathematical and Numerical Aspects of Wave Propagation, Reading University, pages 47-49, 2007.
  43. S. Langdon and S. N. Chandler-Wilde. Implementation of a boundary element method for high frequency scattering by convex polygons. Proc. 5th U.K. Conf. on Boundary Integral Methods, (K. Chen ed.), pages 2-11, 2005.
  44. S. Langdon, M. Ganesh and I. H. Sloan. Approximation of high frequency acoustic wave surface integrals. Proc. 7th Int. Conf. on Mathematical and Numerical Aspects of Wave Propagation, Brown University, Providece, RI, pages 157-159, 2005.
  45. S. N. Chandler-Wilde and S. Langdon. A boundary element method for high frequency scattering by convex polygons. Proc. 7th Int. Conf. on Mathematical and Numerical Aspects of Wave Propagation, Brown University, Providece, RI, pages 151-153, 2005.
  46. S. Langdon and S. N. Chandler-Wilde. A GTD-based boundary element method for a surface scattering problem. Proceedings of the Institute of Acoustics 25(5), pages 224-233, 2003.
  47. S. Langdon and S. N. Chandler-Wilde. A Galerkin boundary element method for an acoustic scattering problem, with convergence rate independent of frequency. Proc. 4th U.K. Conf. on Boundary Integral Methods, (S. Amini ed.), pages 67-76, Salford University Press 2003.
  48. S. N. Chandler-Wilde, S. Langdon and L. Ritter. A Galerkin boundary element method for a high frequency scattering problem. Proc. 6th Int. Conf. on Mathematical and Numerical Aspects of Wave Propagation, University of Jyväskylä, Finland (G. C. Cohen, E. Heikkola, P. Joly and P. Neittaanmäki, eds), pages 257-262, Springer-Verlag, Berlin 2003.
  49. S. Langdon. A boundary integral equation method for the heat equation. Proc. 5th Int. Conf. on Integral Methods in Science and Engineering (IMSE98), Michigan Technological University, (A. Struthers and B. Bertram, editors), pages 211-216.. Boca Raton FL: CRC 2000.
  50. Other publications

  51. S. Langdon, N. Biggs, P. Chamberlain and J.-R. Li, Editorial for Waves 2007 conference, Journal of Computational and Applied Mathematics, 2009, doi: 10.1016/j.cam.2009.08.006.
  52. Domain Embedding Boundary Integral Equation Methods and Parabolic PDEs, Ph.D. Thesis, University of Bath, 1999.