Optimal L...-Error Estimates for Nonconforming and Mixed Finite Element Methods of Lowest Order.
Optimal Poiseuille flow in a finite elastic dyadic tree
In this paper we construct a model to describe some aspects of the deformation of the central region of the human lung considered as a continuous elastically deformable medium. To achieve this purpose, we study the interaction between the pipes composing the tree and the fluid that goes through it. We use a stationary model to determine the deformed radius of each branch. Then, we solve a constrained minimization problem, so as to minimize the viscous (dissipated) energy in the tree. The key...
Optimization of space-time material layout for 1D wave propagation with varying mass and stiffness parameters
Optimization of the domain in elliptic unilateral boundary value problems by finite element method
Optimization of the shape of axisymmetric shells
Axisymmetric thin elastic shells of constant thickness are considered and the meridian curves of their middle surfaces taken for the design variable. Admissible functions are smooth curves of a given length, which are uniformly bounded together with their first and second derivatives, and such that the shell contains a given volume. The loading consists of the hydrostatic pressure of a liquid, the shell's own weight and the internal or external pressure. As the cost functional, the integral of the...
Optimum beam design via stochastic programming
The purpose of the paper is to discuss the applicability of stochastic programming models and methods to civil engineering design problems. In cooperation with experts in civil engineering, the problem concerning an optimal design of beam dimensions has been chosen. The corresponding mathematical model involves an ODE-type constraint, uncertain parameter related to the material characteristics and multiple criteria. As a~result, a~multi-criteria stochastic nonlinear optimization model is obtained....
Optimum composite material design
Original title unknown
Orthotropic almost cylindrical beams: bending by a transverse load
Oscillations of a nonlinearly damped extensible beam
It is proved that any weak solution to a nonlinear beam equation is eventually globally oscillatory, i.e., there is a uniform oscillatory interval for large times.
Over the evolution of fundamental ideas of fracture mechanics.
Padesát let metody konečných prvků
Parallel solution of elasticity problems using overlapping aggregations
The finite element (FE) solution of geotechnical elasticity problems leads to the solution of a large system of linear equations. For solving the system, we use the preconditioned conjugate gradient (PCG) method with two-level additive Schwarz preconditioner. The preconditioning is realised in parallel. A coarse space is usually constructed using an aggregation technique. If the finite element spaces for coarse and fine problems on structural grids are fully compatible, relations between elements...
Parameters identification of material models based on the inverse analysis
The paper presents an application of the inverse analysis to the identification of two models: a phase transformation model and a rheological model. The optimization algorithm for the inverse analysis was tested for various techniques of searching for the minimum: derivative-free and gradient methods, as well as genetic algorithms. Simulation results were validated for microalloyed niobium steel. An optimization strategy, which is adequate for the inverse analysis, is suggested.
Partial exact controllability and exponential stability in higher-dimensional linear thermoelasticity
Partial exact controllability and exponential stability in higher-dimensional linear thermoelasticity
The problem of partial exact boundary controllability and exponential stability for the higher-dimensional linear system of thermoelasticity is considered. By introducing a velocity feedback on part of the boundary of the thermoelastic body, which is clamped along the rest of its boundary, to increase the loss of energy, we prove that the energy in the system of thermoelasticity decays to zero exponentially. We also give a positive answer to a related open question raised by Alabau and Komornik...
Partial Regularity for Certain classes for Polyconvex functionals Related to Nonlinear Elasticity.
Peltier effect of superconductor-semiconductor mesoscopic device.
Performance of composite implicit time integration scheme for nonlinear dynamic analysis.
Periodic homogenization of a non-coercive class of functionals.