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We present a Machine Learning-based method for tomographic reconstruction of dense layered objects, with range of projection angles limited to $\pm $10$^\circ$. Whereas previous approaches to phase tomography generally require two steps,…

Image and Video Processing · Electrical Eng. & Systems 2020-01-08 Alexandre Goy , Girish Rughoobur , Shuai Li , Kwabena Arthur , Akintunde I. Akinwande , George Barbastathis

Deep learning (DL) has shown unprecedented performance for many image analysis and image enhancement tasks. Yet, solving large-scale inverse problems like tomographic reconstruction remains challenging for DL. These problems involve…

Medical Physics · Physics 2019-12-18 Lin Fu , Bruno De Man

A convex partition of a point set P in the plane is a planar partition of the convex hull of P with empty convex polygons or internal faces whose extreme points belong to P. In a convex partition, the union of the internal faces give the…

Computational Geometry · Computer Science 2020-12-16 Hadrien Cambazard , Nicolas Catusse

High resolution reconstruction of complicated objects from incomplete and noisy data can be achieved by solving modulation equations iteratively under physical constraints. This direct demodulation method is a powerful technique for dealing…

Astrophysics · Physics 2009-11-10 Ti-Pei Li , Mei Wu

We consider the Minimum Coverage Kernel problem: given a set $B$ of $d$-dimensional boxes, find a subset of $B$ of minimum size covering the same region as $B$. This problem is $\mathsf{NP}$-hard, but as for many $\mathsf{NP}$-hard problems…

Computational Geometry · Computer Science 2018-05-17 Jérémy Barbay , Pablo Pérez-Lantero , Javiel Rojas-Ledesma

Folding is emerging as a promising manufacturing process to transform flat materials into functional structures, offering efficiency by reducing the need for welding, gluing, and molding, while minimizing waste and enabling automation.…

Soft Condensed Matter · Physics 2025-10-20 João C. Neves , Bernardo R. Marques , Cristóvão S. Dias , Nuno A. M. Araújo

Dimensionality reduction is an essential technique for multi-way large-scale data, i.e., tensor. Tensor ring (TR) decomposition has become popular due to its high representation ability and flexibility. However, the traditional TR…

Numerical Analysis · Mathematics 2024-12-20 Longhao Yuan , Chao Li , Jianting Cao , Qibin Zhao

Pattern self-assembly tile set synthesis (PATS) is a combinatorial optimization problem which aim at minimizing a rectilinear tile assembly system (RTAS) that uniquely self-assembles a given rectangular pattern, and is known to be NP-hard.…

Computational Complexity · Computer Science 2013-01-17 Shinnosuke Seki

Tilings of the plane resemble the simplicial and other complexes from algebraic topology, but have not been studied from this perspective. We construct finite categories corresponding to polygons with labeled directed edges, and introduce…

Category Theory · Mathematics 2025-09-09 Catherine DiLeo , Preston Sessoms , Brandon T. Shapiro

Ptychography has rapidly grown in the fields of X-ray and electron imaging for its unprecedented ability to achieve nano or atomic scale resolution while simultaneously retrieving chemical or magnetic information from a sample. A…

Image and Video Processing · Electrical Eng. & Systems 2020-04-20 Mathew J. Cherukara , Tao Zhou , Youssef Nashed , Pablo Enfedaque , Alex Hexemer , Ross J. Harder , Martin V. Holt

Throughout the evolution of the neural networks more specialized cells were added to the set of basic building blocks. These cells aim to improve training convergence, increase the overall performance, and reduce the number of required…

Computer Vision and Pattern Recognition · Computer Science 2018-11-21 Andrey Filippov , Oleg Dzhimiev

A matrix is given in ``shredded'' form if we are presented with the multiset of rows and the multiset of columns, but not told which row is which or which column is which. The matrix is reconstructible if it is uniquely determined by this…

Combinatorics · Mathematics 2024-01-11 Paul Balister , Gal Kronenberg , Alex Scott , Youri Tamitegama

We consider a problem concerning tilings of rectangular regions by a finite library of polyominoes. We specifically look at rectangular regions of dimension $n\times m$ and ask whether or not a tiling of this region can be rearranged so…

Combinatorics · Mathematics 2016-06-20 Jacob Turner

The problem of packing a set of circles into the smallest surrounding container is considered. This problem arises in different application areas such as automobile, textile, food, and chemical industries. The so-called circle packing…

Optimization and Control · Mathematics 2024-01-02 Rabia Taşpınar , Burak Kocuk

The architecture of neural Turing machines is differentiable end to end and is trainable with gradient descent methods. Due to their large unfolded depth Neural Turing Machines are hard to train and because of their linear access of…

Neural and Evolutionary Computing · Computer Science 2016-12-08 Janez Aleš

Given a collection of N rectangles such that the side ratio of each one is a quadratic irrationality, we find all rectangles which can be tiled by rectangles similar to one of the given ones. It means that each possible shape can be used…

Combinatorics · Mathematics 2016-12-06 Fyodor Sharov

The reconstruction of an unknown function $f$ from its line sums is the aim of discrete tomography. However, two main aspects prevent reconstruction from being an easy task. In general, many solutions are allowed due to the presence of the…

Combinatorics · Mathematics 2021-04-20 Matthew Ceko , Silvia M. C. Pagani , Rob Tijdeman

In the classic circle packing problem, one asks whether a given set of circles can be packed into a given container. Packing problems like this have been shown to be $\mathsf{NP}$-hard. In this paper, we present new sufficient conditions…

Computational Geometry · Computer Science 2018-06-28 Sándor P. Fekete , Sebastian Morr , Christian Scheffer

Plasma tomography consists in reconstructing the 2D radiation profile in a poloidal cross-section of a fusion device, based on line-integrated measurements along several lines of sight. The reconstruction process is computationally…

Computational Physics · Physics 2018-02-08 Diogo R. Ferreira , Pedro J. Carvalho , Horácio Fernandes

Computations, where the number of results is much smaller than the input data and are produced through some sort of accumulation, are called Reductions. Reductions appear in many scientific applications. Usually, reductions admit an…

Programming Languages · Computer Science 2018-01-19 Nirmal Prajapati