This paper analyzes the effect of velocity filtering cut-off frequency on the Z-width performance in haptic interfaces. Finite Difference Method (FDM) cascaded with a lowpass filter is the most commonly used technique for estimating velocity from position data in haptic interfaces. So far, there is no prescribed method for obtaining the FDM+filter cut-off frequency that will maximize the Z-widt...

The field of two-dimensional filters and their design methods have been approached by many researchers, for more than three decades (Lim, 1990; Lu & Antoniou, 1992). A commonly-used design technique for 2D filters is to start from a specified 1D prototype filter and transform its transfer function using various frequency mappings in order to obtain a 2D filter with a desired frequency response....

This paper presents a retinal vessel segmentation method that is inspired by the human visual system and uses a Gabor filter bank. Machine learning is used to optimize the filter parameters for retinal vessel extraction. The filter responses are represented as textons and this allows the corresponding membership functions to be used as the framework for learning vessel and non-vessel classes. T...

Explicit solutions are given for the rational function P (z) for two classes of IIR orthogonal two-band wavelet bases, for which the scaling filter is maximally flat. P (z) denotes the rational transfer function H(z)H(1=z), where H(z) is the (lowpass) scaling filter. The first is the class of solutions that are intermediate between the Daubechies and the Butterworth wavelets. It is found that t...

In this work we provide polyphase, modulation, and frame theoretical analyses of a filter bank on a discrete abelian group. Thus, multidimensional or cyclic filter banks as well as filter banks for signals in `(Z×Zs) or `(Zr ×Zs) spaces are studied in a unified way. We obtain perfect reconstruction conditions and the corresponding frame bounds.

In the paper, we consider the problem of designing a filter that, operating on noisy measurements of input u and output y of a dynamical system, gives estimates (possibly optimal in some sense) of some other variable of interest z. A large body of literature exists, which investigates this problem assuming that the system equations relating u, y and z are known. However, in most practical situa...

This document provides solutions to the exercises in “Iterated Ultrapowers for the Masses”. 3.3. Exercise. Let U be anM-amenable ultrafilter on the parametricallyM-definable subsets of M . We begin by showing that U2 is a filter on the parametricallyM-definable subsets of M2. Let X,Y ⊆M2 be parametrically M-definable. Let Z = {m ∈M : (X ∩ Y )|m ∈ U}, Z1 = {m ∈M : X|m ∈ U}, Z2 = {m ∈M : Y |m ∈ U...

The problem of optimal Weighted Order Statistics (WOS) filters design is first related to the optimal design in a larger class, called Variable Rank Order Statistics (VROS) filters, the results obtained p r e viding guidelines for the approach to be used in WOS filtering. Since adaptive methods applied directly to WOS filter models have to cope with a very ill conditioned problem, the adaptatio...

This article presents a selection analysis of the parameters used for a half-band filter in a digital Hilbert transformer. The parameters were determined for the transformer’s use in measuring Budeanu reactive power. This solution allowed to check the operation of the filter by comparing the results obtained with the filter with the results of Budeanu reactive power obtained in the frequency do...

White-light interferometry is a technique of profiling surface topography of objects such as semiconductors, liquid crystal displays (LCDs), and so on. The world fastest surface profiling algorithm utilizes a generalized sampling theorem that reconstructs the squared-envelope function r(z) directly from an infinite number of samples of the interferogram f(z). In practical measurements, however,...