Structural Health Monitoring (SHM) system requires a fast and accurate algorithm for defect detections in the large structures like aircraft skins for which Lamb wave tomography (LWT) appears to be very powerful technique, as their propagation properties depend on the thickness and the mechanical properties of the material. Projection data is collected by electronically scanning an array of ult...

A method is proposed to reconstruct signals from incomplete data. The method, which can be interpreted both as a discrete implementation of the so-called prior discrete Fourier transform (PDFT) spectral estimation technique and as a variant of the algebraic reconstruction technique, allows one to incorporate prior information about the reconstructed signal to improve the resolution of the signa...

Operator Discretization Library (ODL) is an open-source Python library for prototyping reconstruction methods for inverse problems, and ASTRA is a high-performance Matlab/Python toolbox for large-scale tomographic reconstruction. The paper demonstrates the feasibility of combining ODL with ASTRA to prototype complex reconstruction methods for discrete tomography. As a case in point, we consider...

The shape of a crystal growing from a supercooled pure melt is influenced by the temperature-dependent kinetics of the nucleation on the interface. In the course of this growth, heat is released from the interface, thus feeding back on the temperature field. In this intrinsically nonlinear process, the three-dimensional temperature field in the fluid is a vital dynamic parameter which has not b...

In this paper, we present an iterative algorithm for reconstructing a three-dimensional density function from a set of two dimensional electron microscopy images. By minimizing an energy functional consisting of a fidelity term and a regularization term, an L(2)-gradient flow is derived. The flow is integrated by a finite element method in the spatial direction and an explicit Euler scheme in t...

We study phase retrieval from rank-one magnitude and more general linear magnitude measurements of an unknown signal as an algebraic estimation problem. It is verified that a certain number of generic rank-one or generic linear measurements are sufficient to enable signal reconstruction for generic signals, and slightly more generic measurements yield reconstructability for all signals. Our res...

The 3D reconstruction of medical images plays an important role in modern clinical diagnosis. Although the analytic-based, iterative-based and deep learning-based methods have been popularly used, there are still many problems to deal with. analysis-based not accurate enough, iteration-based computationally intensive, learning based heavily dependent on training data. To solve default that only...

the problem of downward continuation of the gravity field from the earth’s surface to the reference ellipsoid arises from the fact that the solution to the boundary value problem for geoid determination without applying stokes formula is sought in terms of the disturbing potential on the ellipsoid but the disturbing gravity observations are only available on the earth’s surface. downward contin...

Accurate segmentation of nanoparticles within various matrix materials is a difficult problem in electron tomography. Due to artifacts related to image series acquisition and reconstruction, global thresholding of reconstructions computed by established algorithms, such as weighted backprojection or SIRT, may result in unreliable and subjective segmentations. In this paper, we introduce the Par...