Ústav matematiky a deskriptivní geometrie
Browse by
Recent Submissions
-
Asymptotic behavior of solutions of a second-order nonlinear discrete equation of Emden-Fowler type
(De Gruyter, 2023-10-06)The article investigates a second-order nonlinear difference equation of Emden-Fowler type. New conditions with respect to parameters of equation are found such that the equation admits a solution asymptotically represented ... -
Micromechanical aspects of the effect of temperature and local plastic strain magnitude on the fracture tughness of ferrite steels
(Elsevier, 2023-01-18)The paper shows that the influence of plastic strain and temperature on the rate of crack nuclei (CN) formation is a crucial factor controlling the shape of the temperature dependence of fracture toughness and its scatter ... -
Crack growth modelling in cementitious composites using XFEM
(Elsevier, 2023-01-18)The article focuses on modelling origin damage to heterogeneous materials, especial-ly to the issue of modelling the formation and propagation of cracks in fibre cementitious compo-sites, which leads to total degradation ... -
On a computational stress-based non-local damage model for quasi-brittle composites
(Elsevier, 2023-01-18)Numerical models for the stress and strain analysis of quasi-brittle composites, such as cement-based ones, supplied by various stiffening particles, under mechanical, thermal, etc. loads should handle i) the creation of ... -
Geodesic mappings onto generalized m-Ricci-symmetric spaces
(MDPI, 2022-06-21)In this paper, we study geodesic mappings of spaces with affine connections onto generalized 2-, 3-, and m-Ricci-symmetric spaces. In either case, the main equations for the mappings are obtained as a closed system of ... -
Canonical Almost Geodesic Mappings of the First Type of Spaces with Affine Connections onto Generalized m-Ricci-Symmetric Spaces
(MDPI, 2021-03-22)In the paper we consider almost geodesic mappings of the first type of spaces with affine connections onto generalized 2-Ricci-symmetric spaces, generalized 3-Ricci-symmetric spaces, and generalized m-Ricci-symmetric spaces. ... -
Incorporation of temperature and plastic strain effects into local approach to fracture
(MDPI, 2021-10-15)An unjustified simplification of the local quantitative criterion regarding cleavage nucleation is a key problem in the utilisation of the Local Approach to Fracture (LA), particularly to predict the fracture toughness ... -
Lower and upper estimates of semi-global and global solutions to mixed-type functional differential equations
(De Gruyter, 2022-02-14)In the paper, nonlinear systems of mixed-type functional differential equations are analyzed and the existence of semi-global and global solutions is proved. In proofs, the monotone iterative technique and Schauder-Tychonov ... -
On a computational approach to micro- and macro-modelling of damage in brittle and quasi-brittle materials
(NAUN, 2020-10-20)Computational modelling of damage in brittle and quasi-brittle materials needs some coupling between micro- and macroscopic crack initiation and evolution, up to their non-negligible softening behaviour. Most such ap-proaches ... -
Geodesic Mappings of Spaces with Affine Connections onto Generalized Symmetric and Ricci-Symmetric Spaces
(MDPI, 2020-09-01)In the paper, we consider geodesic mappings of spaces with an affine connections onto generalized symmetric and Ricci-symmetric spaces. In particular, we studied in detail geodesic mappings of spaces with an affine connections ... -
Analysis of temperature degraded concrete at high temperature by applying of non-linear characteristics
(IOP Publishing, 2018-07-12)Concrete structures are commonly exposed to thermal loads as a result of the structure, ambient conditions, the heat of hydration, or exposure to fire. Therefore, there has been a growing interest in the research of advanced ... -
Conformal and Geodesic Mappings onto Some Special Spaces
(MDPI, 2019-07-25)In this paper, we consider conformal mappings of Riemannian spaces onto Ricci-2-symmetric Riemannian spaces and geodesic mappings of spaces with affine connections onto Ricci-2-symmetric spaces. The main equations for the ... -
Hybrid Genetic Algorithm-Based Approach for Estimating Flood Losses on Structures of Buildings
(MDPI, 2020-04-10)Occurrence of extreme natural events raises the need for a quick and accurate estimation of losses on the insured residential property in order to support timely recovery of the area. Although various models are now available ... -
Experimental Increase in the Efficiency of a Cooling Circuit Using a Desuperheater
(Budapest University of Technology and Economics, 2016-05-02)Waste heat from cooling circuits can be a useful source of energy for other applications, such as domestic hot water heaters. Furthermore, by removing waste heat from the cooling circuit, its effectiveness can theoretically ... -
Infinitesimal Transformations of Locally Conformal Kähler Manifolds
(MDPI, 2019-07-24)The article is devoted to infinitesimal transformations. We have obtained that LCK-manifolds do not admit nontrivial innitesimal projective transformations. Then we study innitesimal conformal transformations of LCK-manifolds. ... -
Conditional Stability and Asymptotic Behavior of Solutions of Weakly Delayed Linear Discrete Systems in R^2
(Hindawi, 2017-06-12)Two-dimensional linear discrete systems $$ x(k+1)=Ax(k)+\sum\limits_{l=1}^{n}B_{l}x_{l}(k-m_{l}),\,\,\,k\ge 0 $$are analyzed, where $m_{1}, m_{2},\dots, m_{n}$ are constant integer delays, $0<m_{1}<m_{2}<\dots<m_{n}$, $A$, ... -
A dynamical system with random parameters as a mathematical model of real phenomena
(MDPI, 2019-10-30)In many cases, it is difcult to nd a solution to a system of difference equations with random structure in a closed form. Thus, a random process, which is the solution to such a system, can be described in another way, for ... -
There Are No Conformal Einstein Rescalings of Pseudo-Riemannian Einstein Spaces with n Complete Light-Like Geodesics
(MDPI, 2019-09-01)In the present paper, we study conformal mappings between a connected n-dimension pseudo-Riemannian Einstein manifolds. -
Exponential stability of perturbed linear discrete systems
(Springer, 2016-01-29)V člá nku je studována exponenciální stabilita a konvergence řešení homogenní perturbované soustavy lineárních diskrétních systémů. Nová kritéria exponenciální stability jsou odvozena pomocí druhé metody Ljapunova. Jsou ... -
The Priestley-Chao Estimator of Conditional Density with Uniformly Distributed Random Design
(Český statistický úřad, 2018-09-21)The present paper is focused on non-parametric estimation of conditional density. Conditional density can be regarded as a generalization of regression thus the kernel estimator of conditional density can be derived from ...
RSS 1.0