Homeomorphisms and generalized derivatives

The generalized Lefschetz number of homeomorphisms on punctured disks

We compute the generalized Lefschetz number of orientation-preserving selfhomeomorphisms of a compact punctured disk, using the fact that homotopy classes of these homeomorphisms can be identified with braids. This result is applied to study Nielsen-Thurston canonical homeomorphisms on a punctured disk. We determine, for a certain class of braids, the rotation number of the corresponding canoni...

Backpropagation generalized for output derivatives

Backpropagation algorithm is the cornerstone for neural network analysis. Paper extends it for training any derivatives of neural network’s output with respect to its input. By the dint of it feedforward networks can be used to solve or verify solutions of partial or simple, linear or nonlinear differential equations. This method vastly differs from traditional ones like finite differences on a...

Generalized Derivatives and Approximation by Polynomials*

Unstable Homeomorphisms

Let M be a metric space and let 4>(M) = M be a homeomorphism. 0(m) = X^d^w) is called the orW of m^M under «2> • ■ • (»i<m2...

Approximation of Hölder continuous homeomorphisms by piecewise affine homeomorphisms

This paper is concerned with the problem of approximating a homeomorphism by piecewise affine homeomorphisms. The main result is as follows: every homeomorphism from a planar domain with a polygonal boundary to R that is globally Hölder continuous of exponent α ∈ (0, 1], and whose inverse is also globally Hölder continuous of exponent α can be approximated in the Hölder norm of exponent β by pi...