Zobrazeno 1 - 10
of 51
pro vyhledávání: '"Erkki Laitinen"'
Publikováno v:
Forests, Vol 11, Iss 2, p 226 (2020)
The weakness of the population matrix models is that they do not take into account the variation inside the class. In this study, we introduce an approach to add height variation of the trees to the diameter-structured matrix models. In this approach
Externí odkaz:
https://doaj.org/article/4e53a860da014bd0928469e29aae8f80
Publikováno v:
Mathematical and Computational Applications, Vol 23, Iss 2, p 31 (2018)
We consider a general problem of optimal allocation of limited resources in a wireless telecommunication network. The network users are divided into several different groups (or classes), which correspond to different levels of service. The network m
Externí odkaz:
https://doaj.org/article/87f36482a34c43ec8c7d6cb70c0b4fc3
Publikováno v:
Mathematical and Computational Applications, Vol 23, Iss 2, p 22 (2018)
We solve numerically a forest management optimization problem governed by a nonlinear partial differential equation (PDE), which is a size-structured population model. The formulated problem is supplemented with a natural constraint for a solution to
Externí odkaz:
https://doaj.org/article/6dbcd842f48243c783d0ab72250050ad
Autor:
Alexander Lapin, Erkki Laitinen
Publikováno v:
Russian Journal of Numerical Analysis and Mathematical Modelling. 37:221-229
A homogeneous Dirichlet initial-boundary value problem for a quasilinear parabolic equation with a time-fractional derivative and coefficients at the elliptic part that depend on the gradient of the solution is considered. Conditions on the coefficie
Autor:
Juho Luukkonen, Aarne Pohjonen, Seppo Louhenkilpi, Jyrki Miettinen, Mikko J. Sillanpää, Erkki Laitinen
Publikováno v:
Metallurgical and Materials Transactions B.
Continuous cooling transformation (CCT) diagrams can be constructed by empirical methods, which is expensive and time consuming, or by fitting a model to available experimental data. Examples of data-driven models implemented so far include regressio
Autor:
A. V. Lapin, Erkki Laitinen
Publikováno v:
Lobachevskii Journal of Mathematics. 42:1706-1714
Abstract A quasilinear parabolic problem with a time fractional derivative of the Caputo type and mixed boundary conditions is considered. The coefficients of the elliptic operator depend on the gradient of the solution, and this operator is uniforml
Autor:
A. V. Lapin, Erkki Laitinen
Publikováno v:
Lobachevskii Journal of Mathematics. 41:2664-2672
A mathematical model and numerical method for simulation of the continuous casting process in a variable in time domain are presented. The variable geometry of the slab is caused by the change in time of the width of the mould. The mathematical model
Publikováno v:
Journal of Applied and Industrial Mathematics. 14:92-103
We propose some simplified modifications of the partial linearization method for network equilibrium problems with mixed demand. In these modifications, the auxiliary direction choice problem is solved approximately. In the modifications, the basic c
Autor:
Alexander Lapin, Erkki Laitinen
Publikováno v:
Lobachevskii Journal of Mathematics. 40:479-488
We solve finite-difference approximations of a linear-quadratic optimal control problem governed by Dirichlet boundary value problem with fractional time derivative. The state equation of the problem is approximated using locally one-dimensional diff
Publikováno v:
SSRN Electronic Journal.