Inverse Problems and Imaging最新文献

Inverse problems of identifying the time-dependent source coefficient for subelliptic heat equations 确定亚椭圆热方程随时间变化的源系数的逆问题

IF 1.3 4区数学

Inverse Problems and Imaging Pub Date : 2023-06-01 DOI: 10.3934/ipi.2023056

M. Ismailov, T. Ozawa, D. Suragan

引用次数: 0

An inverse potential problem for the stochastic diffusion equation with a multiplicative white noise 含乘性白噪声随机扩散方程的一个反势问题

IF 1.3 4区数学

Inverse Problems and Imaging Pub Date : 2023-02-07 DOI: 10.3934/ipi.2023032

Xiaoli Feng, Peijun Li, Xu Wang

引用次数: 0

Visibility, invisibility and unique recovery of inverse electromagnetic problems with conical singularities 具有圆锥奇点的电磁逆问题的可见性、不可见性和唯一恢复

4区数学

Inverse Problems and Imaging Pub Date : 2023-01-01 DOI: 10.3934/ipi.2023043

Huaian Diao, Xiaoxu Fei, Hongyu Liu, Ke Yang

引用次数: 1

How to best combine demosaicing and denoising? 如何最好地将去马赛克和去噪结合起来?

4区数学

Inverse Problems and Imaging Pub Date : 2023-01-01 DOI: 10.3934/ipi.2023044

Yu Guo, Qiyu Jin, Jean-Michel Morel, Gabriele Facciolo

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引用次数: 0

Nonlinearity parameter imaging in the frequency domain 频域非线性参数成像

4区数学

Inverse Problems and Imaging Pub Date : 2023-01-01 DOI: 10.3934/ipi.2023037

Barbara Kaltenbacher, William Rundell

引用次数: 0

Deblurring photographs of characters using deep neural networks 使用深度神经网络去模糊人物照片

4区数学

Inverse Problems and Imaging Pub Date : 2023-01-01 DOI: 10.3934/ipi.2022057

Thomas Germer, Tobias Uelwer, Stefan Harmeling

引用次数: 1

Explainable bilevel optimization: An application to the Helsinki deblur challenge 可解释的双层优化:赫尔辛基去模糊挑战的应用程序

4区数学

Inverse Problems and Imaging Pub Date : 2023-01-01 DOI: 10.3934/ipi.2022055

Silvia Bonettini, Giorgia Franchini, Danilo Pezzi, Marco Prato

{"title":"Explainable bilevel optimization: An application to the Helsinki deblur challenge","authors":"Silvia Bonettini, Giorgia Franchini, Danilo Pezzi, Marco Prato","doi":"10.3934/ipi.2022055","DOIUrl":"https://doi.org/10.3934/ipi.2022055","url":null,"abstract":"In this paper we present a bilevel optimization scheme for the solution of a general image deblurring problem, in which a parametric variational-like approach is encapsulated within a machine learning scheme to provide a high quality reconstructed image with automatically learned parameters. The ingredients of the variational lower level and the machine learning upper one are specifically chosen for the Helsinki Deblur Challenge 2021, in which sequences of letters are asked to be recovered from out-of-focus photographs with increasing levels of blur. Our proposed procedure for the reconstructed image consists in a fixed number of FISTA iterations applied to the minimization of an edge preserving and binarization enforcing regularized least-squares functional. The parameters defining the variational model and the optimization steps, which, unlike most deep learning approaches, all have a precise and interpretable meaning, are learned via either a similarity index or a support vector machine strategy. Numerical experiments on the test images provided by the challenge authors show significant gains with respect to a standard variational approach and performances comparable with those of some of the proposed deep learning based algorithms which require the optimization of millions of parameters.","PeriodicalId":50274,"journal":{"name":"Inverse Problems and Imaging","volume":"239 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135076321","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"数学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 2

On recovering the nonlinearity for generalized higher-order Schrödinger equations 广义高阶Schrödinger方程的非线性恢复

4区数学

Inverse Problems and Imaging Pub Date : 2023-01-01 DOI: 10.3934/ipi.2023039

Zachary Lee, Xueying Yu

引用次数: 2

On trajectories of complex-valued interior transmission eigenvalues 关于复值内传输特征值的轨迹

4区数学

Inverse Problems and Imaging Pub Date : 2023-01-01 DOI: 10.3934/ipi.2023041

Lukas Pieronek, Andreas Kleefeld

引用次数: 0

Error estimation to the direct sampling method for the inverse acoustic source problem with multi-frequency data 多频数据反声源问题直接采样方法的误差估计