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Living biological tissue is a complex system, constantly growing and changing in response to external and internal stimuli. These processes lead to remarkable and intricate changes in shape. Modeling and understanding both natural and…

Computer Vision and Pattern Recognition · Computer Science 2025-04-07 Edwin Tay , Nazli Tümer , Amir A. Zadpoor

We describe algorithms based on invariant theory to solve problems on the geometry of curves, mainly those of genus 2, 3 and 4. New theoretical results building on the first author's PhD thesis are also included.

Algebraic Geometry · Mathematics 2026-03-11 Thomas Bouchet , Reynald Lercier , Jeroen Sijsling , Christophe Ritzenthaler

Copulas, generalized estimating equations, and generalized linear mixed models promote the analysis of grouped data where non-normal responses are correlated. Unfortunately, parameter estimation remains challenging in these three…

Methodology · Statistics 2024-10-16 Sarah S. Ji , Benjamin B. Chu , Hua Zhou , Kenneth Lange

We propose a new method for simulating QCD at finite density. The method is based on a general factorization property of distribution functions of observables, and it is therefore applicable to any system with a complex action. The…

High Energy Physics - Lattice · Physics 2017-08-23 Jun Nishimura

Non-Gaussian shapes, despite a linear form of the mean-squared displacement, have been observed for the displacement distribution in a large range of diffusive systems. Stochastic models for such "Brownian yet non-Gaussian" diffusion will…

Statistical Mechanics · Physics 2022-04-05 R. Metzler , A. V. Chechkin

The entropy region is constructed from vectors of random variables by collecting Shannon entropies of all subvectors. Its shape is studied here by means of polymatroidal constructions, notably by convolution. The closure of the region is…

Information Theory · Computer Science 2013-10-23 František Matúš , Lászlo Csirmaz

Existing ultrasound deconvolution approaches unrealistically assume, primarily for computational reasons, that the convolution model relies on a spatially invariant kernel and circulant boundary conditions. We discard both restrictions and…

Signal Processing · Electrical Eng. & Systems 2021-09-21 Mihai I. Florea , Adrian Basarab , Denis Kouamé , Sergiy A. Vorobyov

Star-shaped bodies are an important nonconvex generalization of convex bodies (e.g., linear programming with violations). Here we present an efficient algorithm for sampling a given star-shaped body. The complexity of the algorithm grows…

Data Structures and Algorithms · Computer Science 2009-04-06 Karthekeyan Chandrasekaran , Daniel Dadush , Santosh Vempala

Special bases of orthogonal polynomials are defined, that are suited to expansions of density and potential perturbations under strict particle number conservation. Particle-hole expansions of the density response to an arbitrary…

Nuclear Theory · Physics 2009-11-11 B. G. Giraud , A. Weiguny , L. Wilets

The derivation of linear response theory within polarizable embedding is carried out from a rigorous quantum-mechanical treatment of a composite system. Two different subsystem decompositions (symmetric and nonsymmetric) of the linear…

Chemical Physics · Physics 2017-10-09 Nanna Holmgaard List , Patrick Norman , Jacob Kongsted , Hans Jørgen Aagaard Jensen

The linear algorithm of the the full non-linear large scale structure of Gaussian random fields is extended here to to perform non-linear CRs. The procedure consists of: (1) Using linear CR of low resolution data to construct a high…

Astrophysics · Physics 2016-08-30 V. Bistolas , Y. Hoffman

A major challenge in the field of nanosciences is the assembly of anisotropic nano objects into aligned structures. The way the objects are aligned determines the physical properties of the final material. In this work, we take a closer…

Materials Science · Physics 2016-04-19 Ulla Vainio

We present a microscopic theory of resonant soft x-ray scattering (RSXS) that accounts for the delocalized character of valence electrons. Unlike past approaches defined in terms of form factors for atoms or clusters, we develop a…

Strongly Correlated Electrons · Physics 2013-04-08 David Benjamin , Dmitry Abanin , Peter Abbamonte , Eugene Demler

Copulas are a powerful tool for modeling multivariate distributions as they allow to separately estimate the univariate marginal distributions and the joint dependency structure. However, known parametric copulas offer limited flexibility…

Machine Learning · Statistics 2021-11-11 Tim Janke , Mohamed Ghanmi , Florian Steinke

We introduce a novel computational framework for digital geometry processing, based upon the derivation of a nonlinear operator associated to the total variation functional. Such operator admits a generalized notion of spectral…

Graphics · Computer Science 2020-09-08 Marco Fumero , Michael Moeller , Emanuele Rodolà

This paper studies formulations of second-order elliptic partial differential equations in nondivergence form on convex domains as equivalent variational problems. The first formulation is that of Smears \& S\"uli [SIAM J.\ Numer.\ Anal.\…

Numerical Analysis · Mathematics 2017-01-17 Dietmar Gallistl

The Taylor expansion of wave fields with respect to shape parameters has a wide range of applications in wave scattering problems, including inverse scattering, optimal design, and uncertainty quantification. However, deriving the high…

Numerical Analysis · Mathematics 2025-03-24 Gang Bao , Haoran Ma , Jun Lai , Jingzhi Li

We study the inverse problem of reconstructing the shape of unknown inclusions in semilinear elliptic equations with nonanalytic nonlinearities, by extending Ikehata's enclosure method to accommodate such nonlinear effects. To address the…

Analysis of PDEs · Mathematics 2025-12-29 Pu-Zhao Kow , Rulin Kuan

In this paper we consider Schwarz domain decomposition applied to the generation of 2D spatial meshes by a local equidistribution principle. We briefly review the derivation of the local equidistribution principle and the appropriate choice…

Numerical Analysis · Mathematics 2013-11-15 Ronald D. Haynes , Alexander J. M. Howse

We summarize our recently proposed approach to quantum field theory on noncommutative curved spacetimes. We make use of the Drinfel'd twist deformed differential geometry of Julius Wess and his group in order to define an action functional…

High Energy Physics - Theory · Physics 2011-03-24 Alexander Schenkel