Now showing items 1-10 of 436
Osmosis for non-electrolyte solvents in permeable periodic porous media
(Peer reviewed, 2016-08)
The paper gives a rigorous description, based on mathematical homogenization theory, for flows of solvents with not charged solute particles under osmotic pressure for periodic porous media permeable for solute particles. The effective Darcy type equations for the flow under osmotic pressure distributed within the porous media are derived. The effective Darcy law contains an additional flux term ...
Homogenization of random Navier–Stokes-type system for electrorheological fluid
(Peer reviewed, 2015-11-19)
The paper deals with homogenization of Navier–Stokes-type system describing electrorheological fluid with random characteristics. Under non-standard growth conditions we construct the homogenized model and prove the convergence result. The structure of the limit equations is also studied.
Asymptotics of a spectral-sieve problem
(Peer reviewed, 2015-11-18)
In a bounded domain with a thin periodically punctured interface we study the limit behavior of the bottom of spectrum for a Steklov type spectral problem, the Steklov boundary condition being imposed on the perforation surface. For a certain range of parameters we construct the effective spectral problem and justify the convergence of eigenpairs.
Time scale Hardy-type inequalities with ‘broken’ exponent p
(Peer reviewed, 2015-01-16)
In this paper, some new Hardy-type inequalities involving ?broken? exponents are derived on arbitrary time scales. Our approach uses both convexity and superquadracity arguments, and the results obtained generalize, complement and provide refinements of some known results in literature
Singularly perturbed spectral problems with Neumann boundary conditions
(Peer reviewed, 2015-09-07)
The paper deals with the Neumann spectral problem for a singularly perturbed second-order elliptic operator with bounded lower order terms. The main goal is to provide a refined description of the limit behaviour of the principal eigenvalue and eigenfunction. Using the logarithmic transformation, we reduce the studied problem to an additive eigenvalue problem for a singularly perturbed Hamilton–Jacobi ...
Some new Hardy-type inequalities in q-analysis
(Peer reviewed, 2016-09)
We derive necessary and sufficient conditions (of Muckenhoupt-Bradley type) for the validity of q -analogs of (r, p) -weighted Hardy-type inequalities for all possible positive values of the parameters r and p . We also point out some possibilities to further develop the theory of Hardy-type inequalities in this new direction.
Some new Hardy-type inequalities for Riemann-Liouville fractional q-integral operator
(Peer reviewed, 2015-09-24)
We consider the q-analog of the Riemann-Liouville fractional q-integral operator of order n∈Nn∈N. Some new Hardy-type inequalities for this operator are proved and discussed.
A decision-support model for operational planning of surface coal mining considering equipment failure
(Peer reviewed; Bokkapittel; Konferansebidrag; Conference object; Chapter, 2016)
This paper presents a decision-support model aiming, primarily, at maximizing the productivity of surface coal mining activities through operational planning and management. The model is formulated based upon mixed integer programming, and it determines the optimal production plan of the shovels and allocation plan of the haul trucks in order to minimize operational cost, fuel consumption as well ...
Two-sided estimates of the Lebesgue constants with respect to Vilenkin systems and applications
(Journal article; Peer reviewed; Tidsskriftartikkel, 2017-03-13)
In this paper, we derive two-sided estimates of the Lebesgue constants for bounded Vilenkin systems, we also present some applications of importance, e.g., we obtain a characterization for the boundedness of a subsequence of partial sums with respect to Vilenkin–Fourier series of H 1 martingales in terms of n's variation. The conditions given in this paper are in a sense necessary and sufficient.
Scenario-based approaches for handling uncertainty in MPC for power system frequency control
(Journal article; Peer reviewed; Tidsskriftartikkel, 2017)
A stochastic nonlinear model predictive controller (SNMPC) is designed for automatic generator control of a proxy of the Nordic power system, and it is compared with a multi-stage nonlinear model predictive controller (MNMPC). Both controllers are scenario based, but originate in two different disturbance modeling paradigms; stochastic and deterministic. A simulation study indicates that the two ...