Realization of the dynamics of ODE's in scalar parabolic PDE's
Regularity for doubly nonlinear parabolic equations
Regularity of potentials and removability of singularities of solutions of partial differential equations
Relaxation lengths and nonnegative solutions in neutron transport
Relaxation oscillations in systems with different time scales
Remarks on the economic criterion - the Internal rate of return
The internal rate of return (IRR) together with the present value (PV) is used as a popular measure for financial project. When used appropriately, it can be a valuable aid in project acceptance or selection. The purpose of this article is to survey the facts about this criterion published so far. More, we investigate the cases of multiple or nonexistent IRRs and try to choose the relevant one and explain its economic meaning.
Remarks to chaotic vibration in nonlinear dynamical systems
Resonance behaviour of the spherical pendulum damper
The pendulum damper modelled as a two degree of freedom strongly non-linear auto-parametric system is investigated using two approximate differential systems. Uni-directional harmonic external excitation at the suspension point is considered. Semi-trivial solutions and their stability are analyzed. The thorough analysis of the non-linear system using less simplification than it is used in the paper [2] is performed. Both approaches are compared and conclusions are drawn.
Riemann problem solutions that are stable to perturbation
Riemann solution for hyperbolic equations with discontinuous coefficients
This paper deals with a Riemann solution for scalar hyperbolic equations with discontinuous coefficients. In many numerical schemes of Godunov type in fluid dynamics, electromagnetic and so on, usually hyperbolic problems are solved to estimate fluxes. The exact solution is generally difficult to obtain, but good approximations are provided in many situations like Roe and HLLC Riemann solvers in fluid. However all these solvers assumes that the acoustic waves speeds are continuous which is not...