Proceedings of the 8th conference of the European Society for Fuzzy Logic and Technology (EUSFLAT-13)

Session: Fuzzy Transform and its Applications

8 articles
Proceedings Article

F-transform and Fuzzy Natural logic in Time Series Analysis

Vilem Novak, Viktor Pavliska, Irina Perfilieva, Martin Stepnicka
This paper continues development of the innovative method of time series analysis and forecasting using special soft-computing techniques: fuzzy transform and Fuzzy Natural Logic. We will demonstrate that the F-transform is a proper technique for extraction of the trend-cycle of time series. Furthermore,...
Proceedings Article

Influence of various types of basic functions on image reconstruction using F-transform

Pavel Vlašánek, Irina Perfilieva
Technique of image reconstruction using Ftransform uses basic functions for computation. Radius and partition of these functions affects quality of the reconstruction. In this article we are focusing on influence of the basic function shape on the quality of reconstruction and providing results of nondecreasing,...
Proceedings Article

Image compression methodology based on fuzzy transform using block similarity

Petr Hurtik, Irina Perfilieva
The aim of the work is to continue in improvement of the image compression based on the F-transform. The image is decomposed into blocks and characterized by the F-transform components. The latter constitutes a simple lossy compression. For better quality of reconstructed images, we compress certain...
Proceedings Article

F^1-transform of Functions of Two Variables

Petra Hodakova, Irina Perfilieva
In this contribution, the F^1-transform of functions of two variables is introduced. It combines properties of the F-transform of functions of two variables and the F^1-transform of functions of one variable. The aim of this study is to prove approximation properties of the F^1-transform components and...
Proceedings Article

Expectile Smoothing using F.transform

Maria Letizia Guerra, Luciano Stefanini
In this paper, we will illustrate the F-transform based on generalized fuzzy partitions as a tool for expectile smoothing. This allows to represent a time series in terms of a fuzzy-valued function whose level-cuts are modeled by F-transform and estimated by expectile regression. The proposed methodology...
Proceedings Article

Hidden functional dependencies found by the technique of F-transform

Jiri Kupka, Iva Tomanova
In this contribution we provide an application of the technique of F-transform. We demonstrate that by using a simple density-based preprocessing, the applicability of F-transform in data analysis can be significantly improved. Despite of the fact that our procedure is demonstrated by a well-known DBSCAN...
Proceedings Article

Analysis of stationary processes using fuzzy transform

Michal Holcapek, Vilem Novak, Irina Perfilieva
In this paper, we show that fuzzy transform originally introduced for a transformation of complex spaces of functions to simpler ones can be used in the analysis of real stationary random processes. We will show that under certain assumptions the fuzzy transform may be used for an approximation of this...
Proceedings Article

On approximation properties of spline based F-transform with respect to fuzzy m-partition

Irina Kodorane, Svetlana Asmuss
In this paper we develop spline based F-transforms by considering fuzzy partitions given by polynomial splines. We investigate approximation properties of such F-transforms and prove that using generalized fuzzy m-partition, which consists of basic functions of bandwidth m, allows us to approximate not...