Function approximation on triangular grids: some numerical results using adaptive techniques

Function approximation on triangular grids: some numerical results using adaptive techniques

Applications of mesh adaption techniques could be found in the numerical solution of PDE’s or in the optimal triangulation of surfaces for shape representation or graphic display. The scope of this work is to verify through numerical experiments the effectiveness of some algorithms for the control of the L∞ error norm for piece–wise linear approximation on 2D unstructured triangular meshes. The...

An Alternative Stability Proof for Direct Adaptive Function Approximation Techniques Based Control of Robot Manipulators

This short note points out an improvement on the robust stability analysis for electrically driven robots given in the paper. In the paper, the author presents a FAT-based direct adaptive control scheme for electrically driven robots in presence of nonlinearities associated with actuator input constraints. However, he offers not suitable stability analysis for the closed-loop system. In other w...

Some results on the block numerical range

The main results of this paper are generalizations of classical results from the numerical range to the block numerical range. A different and simpler proof for the Perron-Frobenius theory on the block numerical range of an irreducible nonnegative matrix is given. In addition, the Wielandt's lemma and the Ky Fan's theorem on the block numerical range are extended.

An Alternative Stability Proof for Direct Adaptive Function Approximation Techniques Based Control of Robot Manipulators

This short note points out an improvement on the robust stability analysis for electrically driven robots given in the paper. In the paper, the author presents a FAT-based direct adaptive control scheme for electrically driven robots in presence of nonlinearities associated with actuator input constraints. However, he offers not suitable stability analysis for the closed-loop system. In other w...

Some Results on p-Best Approximation in Vector Spaces