TY - JOUR T1 - Numerical Identification of Nonlocal Potentials in Aggregation AU - He , Yuchen AU - Kang , Sung Ha AU - Liao , Wenjing AU - Liu , Hao AU - Liu , Yingjie JO - Communications in Computational Physics VL - 3 SP - 638 EP - 670 PY - 2022 DA - 2022/09 SN - 32 DO - http://doi.org/10.4208/cicp.OA-2021-0177 UR - https://global-sci.org/intro/article_detail/cicp/21041.html KW - Aggregation equation, nonlocal potential, PDE identification, Bregman iteration, operator splitting. AB -

Aggregation equations are broadly used to model population dynamics with nonlocal interactions, characterized by a potential in the equation. This paper considers the inverse problem of identifying the potential from a single noisy spatial-temporal process. The identification is challenging in the presence of noise due to the instability of numerical differentiation. We propose a robust model-based technique to identify the potential by minimizing a regularized data fidelity term, and regularization is taken as the total variation and the squared Laplacian. A split Bregman method is used to solve the regularized optimization problem. Our method is robust to noise by utilizing a Successively Denoised Differentiation technique. We consider additional constraints such as compact support and symmetry constraints to enhance the performance further. We also apply this method to identify time-varying potentials and identify the interaction kernel in an agent-based system. Various numerical examples in one and two dimensions are included to verify the effectiveness and robustness of the proposed method.