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In the paper we consider the macroscopic model of plasma of scalar charged particles, obtained by means of the statistical averaging of the microscopic equations of particle dynamics in a scalar field. On the basis of kinetic equations,…

General Relativity and Quantum Cosmology · Physics 2015-06-23 Yurii Ignat'ev , Alexander Agathonov , Mikhail Mikhailov , Dmitry Ignatyev

This paper presents an efficient approach to image segmentation that approximates the piecewise-smooth (PS) functional in [12] with explicit solutions. By rendering some rational constraints on the initial conditions and the final solutions…

Computer Vision and Pattern Recognition · Computer Science 2016-12-09 Huihui Song , Yuhui Zheng , Kaihua Zhang

We present the ContEvol (continuous evolution) formalism, a family of implicit numerical methods which only need to solve linear equations and are almost symplectic. Combining values and derivatives of functions, ContEvol outputs allow…

Instrumentation and Methods for Astrophysics · Physics 2025-12-23 Kaili Cao

This article reports the spherical coordinate form of three-dimensional generalized dynamics of soft-matter quasicrystals with 12-fold symmetry which provides a basis for solving initial-boundary value problems of the equations under some…

Soft Condensed Matter · Physics 2019-10-25 Zhi-Yi Tang , Tian-You Fan

A modeling formalism is proposed for the description and study of living and life-like systems. It provides an abstract conceptual model framework for real life and evolution of biological organisms. It is proposed, that this model…

Populations and Evolution · Quantitative Biology 2013-06-14 Margareta Segerståhl

A phenomenon of classical quantization is discussed. This is revealed in the class of pseudoclassical gauge systems with nonlinear nilpotent constraints containing some free parameters. Variation of parameters does not change local (gauge)…

High Energy Physics - Theory · Physics 2009-10-30 Khazret Nirov , Mikhail Plyushchay

Many standard structural quantities, such as order parameters and correlation functions, exist for common condensed matter systems, such as spherical and rod-like particles. However, these structural quantities are often insufficient for…

Soft Condensed Matter · Physics 2012-01-18 Aaron S. Keys , Christopher R. Iacovella , Sharon C. Glotzer

Factor models are widely used across diverse areas of application for purposes that include dimensionality reduction, covariance estimation, and feature engineering. Traditional factor models can be seen as an instance of linear embedding…

Methodology · Statistics 2020-08-13 Xingchen Yu , Abel Rodriguez

Representing texts as fixed-length vectors is central to many language processing tasks. Most traditional methods build text representations based on the simple Bag-of-Words (BoW) representation, which loses the rich semantic relations…

Computation and Language · Computer Science 2017-07-19 Ruqing Zhang , Jiafeng Guo , Yanyan Lan , Jun Xu , Xueqi Cheng

The present paper considers volume formulae, as well as trigonometric identities, that hold for a tetrahedron in 3-dimensional spherical space of constant sectional curvature +1. The tetrahedron possesses a certain symmetry: namely rotation…

Metric Geometry · Mathematics 2011-08-02 Alexander Kolpakov , Alexander Mednykh , Marina Pashkevich

The paper proposes an algorithm which could identify a general class of pdes describing dynamical systems with similar symmetries. The way that will be followed starts from a given group of symmetries, the determination of the invariants…

Mathematical Physics · Physics 2015-06-03 Rodica Cimpoiasu , Radu Constantinescu

This paper investigates evolution of cosmic structures in different environments. For this purpose the quasispherical Szekeres model is employed. The Szekeres model is an exact solution of the Einstein field equations within which it is…

Astrophysics · Physics 2013-05-29 Krzysztof Bolejko

This paper is concerned with the analysis of a new stable space-time finite element method (FEM) for the numerical solution of parabolic evolution problems in moving spatial computational domains. The discrete bilinear form is elliptic on…

Numerical Analysis · Mathematics 2018-05-14 Stephen Edward Moore

This paper investigates a class of controlled stochastic partial differential equations (SPDEs) arising in the modeling of composite materials with spatially varying properties. The state equation describes the evolution of a material…

Optimization and Control · Mathematics 2025-02-24 Nacira Agram , Isabelle Turpin , Eya Zougar

In this paper, we investigate numerically the stochastic ABC model, a toy model in the theory of astrophysical kinematic dynamos, within the recently proposed supersymmetric theory of stochastics (STS). STS characterises stochastic…

Chaotic Dynamics · Physics 2018-06-19 Igor V. Ovchinnikov , Yuquan Sun , Torsten A. Ensslin , Kang. L. Wang

In this paper we consider the spatial semi-discretization of conservative PDEs. Such finite dimensional approximations of infinite dimensional dynamical systems can be described as flows in suitable matrix spaces, which in turn leads to the…

Numerical Analysis · Mathematics 2022-03-01 Michele Benzi , Milo Viviani

The problem of optimization of a cycle of tangential deformations of the surface of a spherical object (microsquirmer) self-propelling in a viscous fluid at low Reynolds numbers is represented in a noncanonical Hamiltonian form. The…

Fluid Dynamics · Physics 2019-07-11 Victor P. Ruban

We present a class of general prolate and oblate spheroidal spacetimes for the description of cosmic structures in the Universe. They are exact geometries which represent, in an appropriated way, the imbedding of spheroidal matter-energy…

General Relativity and Quantum Cosmology · Physics 2017-01-27 Ezequiel F. Boero , Osvaldo M. Moreschi

Partial symplectic conditional and joint probability representations of quantum mechanics are considered. The correspondence rules for most interesting physical operators are found and the expressions of the dual symbols of operators are…

Quantum Physics · Physics 2024-06-12 Ya. A. Korennoy , V. I. Man'ko

We develop an efficient numerical scheme for the 3D mean-field spherical dynamo equation. The scheme is based on a semi-implicit discretization in time and a spectral method in space based on the divergence-free spherical harmonic…

Numerical Analysis · Mathematics 2019-10-04 Ting cheng , Lina Ma , Jie Shen