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A decoupled physics-informed neural network for recovering a space-dependent force function in the wave equation from integral overdetermination data

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Abstract

In this paper, we study the inverse problem of approximating a space-dependent wave source in a one-dimensional wave equation. The problem is converted to a nonclassical second-order hyperbolic equation and is later reduced to the solution of a linear system of algebraic equations by employing the Ritz collocation method. The obtained Ritz approximation is used to train a physics-informed neural network (PINN). However, unlike the conventional training in PINN, the loss function of the proposed method is not additive and the loss terms are decoupled in the sense that the neural network is re-trained separately according to each loss term. Hence, we name the proposed method decoupled PINN or D-PINN for short. Since the function of the initial condition is nonlinear and continuously differentiable, it is used, up to a scalar, as the activation function as opposed to using an off-the-shelf activation function such as hyperbolic tangent. Experiments indicate that D-PINN is capable of approximating the solution more accurately than Ritz and PINN.

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Notes

  1. In this work we represent the transpose operator by notation tr.

References

  • Baydin AG, Pearlmutter BA, Radul AA, Siskind JM (2017) Automatic differentiation in machine learning: a survey. J Mach Learn Res 18(1):5595–5637

    MathSciNet  MATH  Google Scholar 

  • Bell WW (2004) Special functions for scientists and engineers. Dover Publications, New York

    MATH  Google Scholar 

  • Blechschmidt J, Ernst OG (2021) Three ways to solve partial differential equations with neural networks: a review. GAMM Mitt 44(2):e202100006

    Article  MathSciNet  Google Scholar 

  • Cannon JR, Dunninger DR (1970) Determination of an unknown forcing function in a hyperbolic equation from overspecified data. Ann Mat Pura Appl 1:49–62

    Article  MathSciNet  MATH  Google Scholar 

  • Chen P, Liu, Aihara K, Chen L (2020) Autoreservoir computing for multistep ahead prediction based on the spatiotemporal information transformation. Nat Commun 11(1):1–15

  • Cuomo S, Di Cola VS, Giampaolo F, Rozza G, Raissi M, Piccialli F (2022)Scientific machine learning through physics-informed neural networks: where we are and what’s next. arXiv preprint arXiv:2201.05624

  • Engl HW, Scherzer O, Yamamoto M (1994) Uniqueness and stable determination of forcing terms in linear partial differential equations with overspecified boundary data. Inverse Probl 10:1253–1276

    Article  MathSciNet  MATH  Google Scholar 

  • Gao H, Sun L, Wang J-X (2021) PhyGeoNet: physics-informed geometry-adaptive convolutional neural networks for solving parameterized steady-state PDEs on irregular domain. J Comput Phys 428:110079

    Article  MathSciNet  MATH  Google Scholar 

  • Gao H, Zahr MJ, Wang J-X (2022) Physics-informed graph neural Galerkin networks: a unified framework for solving PDE-governed forward and inverse problems. Comput Methods Appl Mech Eng 390:114502

    Article  MathSciNet  MATH  Google Scholar 

  • Hajimohammadi Z, Parand K (2021) Numerical learning approximation of time-fractional sub diffusion model on a semi-infinite domain. Chaos Solitons Fractals 142:110435

    Article  MathSciNet  MATH  Google Scholar 

  • Hochstadt H (1986) The functions of mathematical physics. Dover Publications Inc., New York

    MATH  Google Scholar 

  • Hussein SO, Lesnic D (2014) Determination of a space-dependent source function in the one-dimensional wave equation. Electron J Bound Elem 12:1–26

    MathSciNet  Google Scholar 

  • Hussein SO, Lesnic D (2016) Determination of forcing functions in the wave equation. Part I: the space-dependent case. J Eng Math 96:115–133

    Article  MathSciNet  MATH  Google Scholar 

  • Isakov V (2006) Inverse problems for partial differential equations. Springer, New York

    MATH  Google Scholar 

  • Jagtap AD, Kawaguchi K, Karniadakis GE (2020a) Adaptive activation functions accelerate convergence in deep and physics-informed neural networks. J Comput Phys 404:109136

    Article  MathSciNet  MATH  Google Scholar 

  • Jagtap AD, Kawaguchi K, Karniadakis GE (2020b) Locally adaptive activation functions with slope recovery for deep and physics-informed neural networks. Proc R Soc A 476:20200334

    Article  MathSciNet  MATH  Google Scholar 

  • Jagtap AD, Kharazmi E, Karniadakis GE (2020c) Conservative physics-informed neural networks on discrete domains for conservation laws: applications to forward and inverse problems. Comput Methods Appl Mech Eng 365:113028

    Article  MathSciNet  MATH  Google Scholar 

  • Jagtap AD, Mao Z, Adams N, Karniadakis GE (2022) Physics-informed neural networks for inverse problems in supersonic flows. arXiv preprint arXiv:2202.11821

  • Jin X, Cai S, Li H, Karniadakis GE (2021) NSFnets (Navier–Stokes flow nets): Physics-informed neural networks for the incompressible Navier–Stokes equations. J Comput Phys 426:109951

    Article  MathSciNet  MATH  Google Scholar 

  • Lesnic D, Hussein SO, Johansson BT (2016) Inverse space-dependent force problems for the wave equation. J Comput Appl Math 306:10–39

    Article  MathSciNet  MATH  Google Scholar 

  • Mao Z, Jagtap AD, Karniadakis GE (2020) Physics-informed neural networks for high-speed flows. Comput Methods Appl Mech Eng 360:112789

    Article  MathSciNet  MATH  Google Scholar 

  • Meer R, Oosterlee CW, Borovykh A (2022) Optimally weighted loss functions for solving pdes with neural networks. J Comput Appl Math 405:113887

    Article  MathSciNet  MATH  Google Scholar 

  • Meronen L, Trapp M, Solin A (2021) Periodic activation functions induce stationarity. Adv Neural Inf Process Syst 34:1673–1685

    Google Scholar 

  • Mishra S, Molinaro R (2022) Estimates on the generalization error of physics-informed neural networks for approximating a class of inverse problems for PDEs. IMA J Numer Anal 42(2):981–1022

    Article  MathSciNet  MATH  Google Scholar 

  • Moseley B, Markham A, Meyer TN (2020) Solving the wave equation with physics-informed deep learning. arXiv preprint arXiv:2006.11894

  • Murray M, Abrol V, Tanner J (2022) Activation function design for deep networks: linearity and effective initialisation. Appl Comput Harmon Anal 59:117–154

    Article  MathSciNet  MATH  Google Scholar 

  • Nguyen LH (2019) An inverse space-dependent source problem for hyperbolic equations and the Lipschitz-like convergence of the quasi-reversibility method. Inverse Probl 35(35):035007. https://doi.org/10.1088/1361-6420/aafe8f

    Article  MathSciNet  MATH  Google Scholar 

  • Prilepko AI, Orlovsky DG, Vasin IA (2000) Methods for solving inverse problems in mathematical physics. Marcel Dekker Inc, New York

    MATH  Google Scholar 

  • Raissi M, Perdikaris P, Karniadakis GE (2019) Physics-informed neural networks: a deep learning framework for solving forward and inverse problems involving nonlinear partial differential equations. J Comput Phys 378:686–707

    Article  MathSciNet  MATH  Google Scholar 

  • Rashedi K (2021) A numerical solution of an inverse diffusion problem based on operational matrices of orthonormal polynomials. Math Method Appl Sci 44:12980–12997

    Article  MathSciNet  MATH  Google Scholar 

  • Rashedi K (2022a) Recovery of coefficients of a heat equation by Ritz collocation method. Kuwaut J Sci. https://doi.org/10.48129/kjs.18581

    Article  MATH  Google Scholar 

  • Rashedi K (2022b) A spectral method based on Bernstein orthonormal basis functions for solving an inverse Roseneau equation. Comput Appl Math. https://doi.org/10.1007/s40314-02226401908-0

    Article  MathSciNet  MATH  Google Scholar 

  • Rashedi K, Baharifard F, Sarraf A (2022) Stable recovery of a space-dependent force function in a one-dimensional wave equation via Ritz collocation method. J Math Model 10:463–480

    MathSciNet  Google Scholar 

  • Samarskii AA, Vabishchevich AN (2007) Numerical methods for solving inverse problems of mathematical physics. Walter de Gruyter, Berlin

    Book  MATH  Google Scholar 

  • Sitzmann V et al (2020) Implicit neural representations with periodic activation functions. Adv Neural Inf Process Syst 33:7462–7473

    Google Scholar 

  • Stoer J, Bulirsch R (1980) Introduction to numerical analysis. Springer, New York

    Book  MATH  Google Scholar 

  • Wei T, Li M (2006) High order numerical derivatives for one-dimensional scattered noisy data. Appl Math Comput 175:1744–1759

    MathSciNet  MATH  Google Scholar 

  • Wen J, Yamamoto M, Wei T (2013) Simultaneous determination of a time-dependent heat source and the initial temperature in an inverse heat conduction problem. Inverse Probl Sci Eng 21:485–499

    Article  MathSciNet  MATH  Google Scholar 

  • Yamamoto M (1995) Stability, reconstruction formula and regularization for an inverse source hyperbolic problem by a control method. Inverse Probl 1:481–496

  • Yuan L et al (2022) A-PINN: auxiliary physics informed neural networks for forward and inverse problems of nonlinear integro-differential equations. J Comput Phys 462:111260

  • Zhang D, Lu L, Guo L, Karniadakis GE (2019) Quantifying total uncertainty in physics-informed neural networks for solving forward and inverse stochastic problems. J Comput Phys 397:108850

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Acknowledgements

The authors are very grateful to the referees for carefully reading the paper and for their comments and suggestions which have led to improvements of the paper.

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Contributions

AS designed the numerical algorithm, implemented the algorithm, and conducted numerical experiments for the neural network approximation. FB worked on writing the introduction, and contributed to the main methodology (the neural network aspect). KR worked on the Ritz approximation of the inverse wave problems, and contributed to the main methodology (the Ritz aspect) and conducted numerical experiments for the Ritz approximation. All authors reviewed the manuscript.

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Correspondence to Aydin Sarraf.

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Communicated by Vinicius Albani.

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Sarraf, A., Baharifard, F. & Rashedi, K. A decoupled physics-informed neural network for recovering a space-dependent force function in the wave equation from integral overdetermination data. Comp. Appl. Math. 42, 178 (2023). https://doi.org/10.1007/s40314-023-02323-9

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  • DOI: https://doi.org/10.1007/s40314-023-02323-9

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