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

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126 articles

Shape Retrieval by Partially Supervised Fuzzy Clustering

Giovanna Castellano, Anna Maria Fanelli, Maria Alessandra Torsello
In this work we propose the use of partially supervised fuzzy clustering to create a two-level indexing structure useful for enabling efficient shape retrieval. Similar shapes are grouped by a fuzzy clustering algorithm that embeds a partial supervision mechanism exploiting domain knowledge expressed...

Evaluation and interval approximation of fuzzy quantities

Luca Anzilli, Gisella Facchinetti, Giovanni Mastroleo
In this paper we present a general framework to face the problem of evaluate fuzzy quantities. A fuzzy quantity is a fuzzy set that may be non normal and/or non convex. This new formulation contains as particular cases the ones proposed by Fortemps and Roubens (1996), Yager and Filev (1981,1999) and...

Forecasting Exchange Rates with Fuzzy Granular Evolving Modeling for Trading Strategies

Leandro Maciel, Fernando Gomide, Rosangela Ballini
This paper addresses a fuzzy set based evolving modeling (FBeM) approach and the task of forecasting exchange rates in order to perform trading strategies. FBeM is a granular computing technique that uses fuzzy information granules to model nonstationary functions providing functional and linguistic...

Fuzzy preference modelling and some consequences for fuzzy implications and quasi-copulas

Dana Hlin ná, Martin Kalina, Pavol Krá
In this paper we study connection between quasi-copulas and generator triples of a fuzzy preference structures. We study also conditions under which fuzzy implications can be used to construct generator triples. As we show, an important property of fuzzy implications that enables us to construct a generator...

On Different Types of Heterogeneous Formal Contexts

Ubomír Antoni, Stanislav Krajči, Ondrej Krídlo
We provide a generalization of another fuzzy formal contexts of Formal Concept Analysis that works with different types of the values in a context. An appropriate counterpart to the so-called basic theorem of concept lattice is formulated. We suggest the process of transformation of heterogeneous formal...

At-least At-most Modifications in a Space with Fuzzy Preoreder

Irina Perfilieva
In this paper, we utilize the theory of solvability of systems of fuzzy relation equations in a space with fuzzy preorder and propose a justification of solvability of the systems that are modified with ``at least'' (``at most'') quantifiers. We show that the respectively modified fuzzy sets are upper...

Efficient GCD functions in SQL

Joachim Nielandt, Antoon Bronselaer, Guy De Tre
Querying a database in an intuitive way is becoming more important. Users expect their tools to present an easy-to-use interface that can interpret complex search criteria. These criteria can be optional, mandatory, unwanted or grouped together, according to what the developer of a tool wishes to offer...

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...

The Structure of the Type-Reduced Set of a Continuous Type-2 Fuzzy Set

Sarah Greenfield, Francisco Chiclana
This paper is concerned with the structure of the type-reduced set (TRS) of the continuous type-2 fuzzy set, in both its interval and generalised forms. In each case the TRS structure is approached by first investigating the discretised set. The TRS of a continuous interval type-2 fuzzy set is shown...

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...

A fuzzy approach for network bandwidth management

Julija Asmuss, Gunars Lauks
The paper deals with the problem of resource allocation in a substrate network with DaVinci architecture. We present a methodology of decision making on network bandwidth allocation based on fuzzification and defuzzification principles and the expert knowledge database of fuzzy rules and we describe...

High-density impulse noise removal using fuzzy mathematical morphology

Manuel González-Hidalgo, Sebastià Massanet, Arnau Mir, Daniel Ruiz-Aguilera
This paper proposes a filtering method for high-density impulse noise removal based on the fuzzy mathematical morphology using t-norms. The method is a two phased method. In the first phase, an impulse noise detector based on the fuzzy top-hat transforms is used to identify pixels which are likely to...

Partial first-order logic relying on optimistic, pessimistic and average partial membership functions

Tamás Mihálydeák
One of the common features of decision-theoretic rough set models is that they rely on total background (available) knowledge in the sense that the knowledge covers the discourse universe. In the proposed framework the author gives up this requirement and allows that available knowledge about the discourse...

Fuzzy Rule-Based Approach for Detecting Adverse Drug Reaction Signal Pairs

Ayman Mansour
Detecting Adverse Drug Reactions (ADR) signal pairs is technically a complex problem. This is the case if we realistically assume that there does not exist a set of rules that are readily acceptable to all human experts (e.g., physicians, epidemiologists and pharmacists). The parameters used in identifying...

New Framework of HSL System Based Color Clustering Algorithm

Vasile Patrascu
In this paper one presents a fuzzy c-means algorithm enhancement for the particular case of color clustering. It was used the perceptual color system for color representation. The main step is represented by definition of a new distance in the color space. In this construction, there were used two multipliers...

Probabilistic Fuzzy Reasoning in a Coherent Setting

Giulianella Coletti, Davide Petturiti, Barbara Vantaggi
We use the interpretation of fuzzy sets in terms of coherent conditional probabilities for handling probabilistic fuzzy IF-THEN rules. We show by some examples how this interpretation can help when fuzzy and statistical information need to be combined and the available probabilistic information on the...

Fuzzy Dissimilarity-Based Classification for Disaster Initial Assessment

J. Tinguaro Rodríguez, Begoña Vitoriano, Javier Montero
conditional probabilities for handling probabilistic fuzzy IF-THEN rules. We show by some examples how this interpretation can help when fuzzy and statistical information need to be combined and the available probabilistic information on the fuzzy events is possibly imprecise or incomplete.

Compatible operations in some subvarieties of the variety of weak Heyting algebras

Hernán San Martín
Weak Heyting algebras are a natural generalization of Heyting algebras (see [2], [5]). In this work we study some subvarieties of the varieties of weak Heyting algebras in order to extend some known results about compatible functions in Heyting algebras.

On a Graded Inclusion of Bipolar Fuzzy Relations

Ludovic Liétard, Olivier Pivert, Daniel Rocacher
This paper deals with database fuzzy queries in the context where the fuzzy preference conditions involved are of a bipolar nature (the first pole corresponding to a constraint, the second to a wish). More precisely, we consider queries where an inclusion-based condition comes into play (a typical example...

Data Reconciliation under Fuzzy Constraints in Material Flow Analysis

Didier Dubois, Hélène Fargier, Dominique Guyonnet
Data reconciliation consists in modifying noisy or unreliable data in order to satisfy a mathematical model (herein a material flow network). The conventional approach relies on least squares minimization. Here we show that the setting of fuzzy sets provides a generalized approach that is more flexible...

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,...

A Stochastic Model for Analyzing the Interpretability-Accuracy Trade-off in Interpretable Fuzzy Systems Using Nested Hyperball Structures

Balázs Krisztián, Koczy Laszlo T.
Our recent work proposed a new meaning preservation approach together with a parameterizable nested hyperball structured search space for interpretable fuzzy systems in order to solve a problem of inconsistency observed in conventional interpretablefuzzy knowledge bases and simultaneously to address...

Triangular norms which are join-morphisms in 3-dimensional fuzzy set theory

Glad Deschrijver
The n-dimensional fuzzy sets have been introduced as a generalization of interval-valued fuzzy sets, Atanassov's intuitionistic and interval-valued intuitionistic fuzzy sets. In this paper we investigate t-norms on 3-dimensional sets which are join-morphisms. Under some additional conditions we show...

Bornological structures in the context of L-fuzzy sets

Alexander Sostak, Ingrida Uljane
In order to apply the concept of boundedness, so crucial in the theory of metric spaces, to the case of a general topological space Hu Sze-Tsen introduced the notions of a bornological space and of boundedness for a mapping of bornological spaces. In this work we discuss two alternative approaches how...

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,...

Weak Preservation of Multi-Valued Fusion

Antoon Bronselaer, Guy De Tre
Fusion functions are important data integration tools that map a multiset of objects (i.e., the sources) onto a single object (i.e., the solution). Traditionally, it is assumed that the objects of interest are single-valued. In this paper, it will be assumed that each object has a multi-valued data structure,...

Solutions of the Distributivity Equation $mathcal{I}(mathcal{T}(x,y),z) = mathcal{S}(mathcal{I}(x,z),mathcal{I}(y,z))$ for Some t-Representable T-Norms and T-Conorms

Michal Baczynski
Recently, in [4], [5], [6], and [8] we have discussed the distributivity equation of implications $mathcal{I}(x,mathcal{T}_1(y,z)) = mathcal{T}_2(mathcal{I}(x,y),mathcal{I}(x,z))$ over t-representable t-norms, generated from (classical) continuous Archimedean mbox{t-norms}, in interval-valued fuzzy sets...

h k aggregation functions, measures and integrals

Fabio Rindone, Salvatore Greco
In many decision making problems evaluations with respect to several points of view (criteria) are ex-pressed by means of h interval (or fuzzy numbers). For example a pessimistic and an optimistic eval-uation generate an interval containing the exact evaluation. These situations reflect lack of infor-mation...

Geometric similarity measures for the intuitionistic fuzzy sets

Eulalia Szmidt, Janusz Kacprzyk
This paper is a continuation of our previous works on geometric similarity measures between Atanassov's intuitionistic fuzzy sets (A-IFSs for short). We consider some traps of the straightforward approach in the case of A-ISs while similarity is understood as a dual concept of a distance. The difficulties...

Towards Smooth Monotonicity in Fuzzy Inference System based on Gradual Generalized Modus Ponens

Phuc-Nguyen Vo, Marcin Detyniecki
Monotonic relationship between input and output often is an inherent property of fuzzy systems. For example, for a cart-pole system, there is a gradual relationship between the pole angle and the cart velocity of the form: ``The more the pole deviates from the upright position, the higher velocity the...

Characterisation of gradual itemsets based on mathematical morphology tools

Amal Oudni, Marie Jeanne Lesot, Maria Rifqi
Gradual itemsets of the form ``the more/less A, the more/less B'' summarise data through the description of their internal tendencies, identified as correlation between attribute values. This paper proposes to characterise gradual itemsets, enriching them with an additional clause introduced by the linguistic...

Bridging Probabilistic and Fuzzy Approaches to Choice Under Uncertainty

Davide Martinetti, Susana Díaz, Susana Montes, Bernard De Baets
Imprecise choices can be described using either a probabilistic or a fuzzy formalism. No relation between them has been studied so far. In this contribution we present a connection between the two formalisms that strongly makes use of fuzzy implication operators and t-norms. In this framework, Luce's...

Optimization of Partly Conflicting Goals in Complex Resource Planning

Rudolf Felix
Many optimization models are limited with respect to the management of inconsistency between the optimization goals. As consequence, these models in many cases achieve results that are optimal for the model but not for the problem. In real world problems the optimization goals are usually partly conflicting....

Investigation of heat waves based on the most typical fuzzy expected values with corresponding trapezoidal membership functions.

Tatiana Kiseliova, Marina Fandoeva, Anna Sikharulidze
In this paper we continue to investigate the important parameter of global warming - a heat wave - that has no unique definition and represents the constellation of different factors such as e.g., heat index (temperature + humidity), time periods of excessive heat, etc. We find typical characteristics...

Distance calculation between Level-2 fuzzy regions

Jörg Verstraete
In many applications, spatial data is often prone to uncertainty and imprecision. To model this, fuzzy regions have been developed. Our initial model was a fuzzy set over a two dimensional domain, allowing for fuzzy regions and fuzzy points to be modelled. The model had some limitations: all points where...

Fuzzification of probabilistic objects

Martin Papco
A categorical approach to probability allows to put basic notions of probability into a broader mathematical perspective, to evaluate their roles, and mutual relationships. Classical probability theory and fuzzy probability theory lead to two particular categories and their relationship (in categorical...

Holistic Preference Learning with the Choquet Integral

Bénédicte Goujon, Christophe Labreuche
The current approaches to construct a multi-criteria model based on a Choquet integral are split into two separate steps: construct first the utility functions and then the aggregation function. Unfortunately, the decision maker may feel some difficulties in addressing these tricky steps. In this paper,...

Reasons for a careful design of fuzzy sets

Enric Trillas, Claudio Moraga
This paper is, basically, a reflection on modeling, starting by asking what happens when the meaning of a predicate P is interpreted by the membership function of a fuzzy set that, labeled P, is designed with the information available to the designer on the use of the predicate in the corresponding universe...

A fuzzy tri-level decision making algorithm and its application in supply chain

Zhen Zhang, Guangquan Zhang, Jie Lu, Chonghui Guo
In this paper, we develop a fuzzy tri-level decision making (FTLDM) model to deal with decentralized decision making problems with three levels of decision makers. Based on the -cut of fuzzy set, we transform an FTLDM problem into a multi-objective multi-follower tri-level decision making problem. Based...

Picking the one that does not fit - A matter of logical proportions

Henri Prade, Gilles Richard
Quiz or tests about reasoning capabilities often pertain to the perception of similarity and dissimilarity between situations. Thus, one may be asked to complete a series of entities $A$, $B$, $C$ by an appropriate $X$, or to pick the one that does not fit in a list. It has been shown that the first...

New results on redundancies of fuzzy/linguistic IF-THEN rules

Lenka Stepnickova, Martin Stepnicka, Antonin Dvorak
In this paper we present new results on detection and removal of redundancies of IF-THEN rules in so-called linguistic descriptions (systems of such rules). We introduce an algorithm for removal of redundancies and describe a practical application.

Fuzzy rule-based ensemble with use linguistic associations mining for time series prediction

Lenka Št pni ková, Martin Stepnicka, David Sikora
There are many various methods to forecast time series. However, there is no single forecasting method that generally outperforms any other. Consequently, there always exists a danger of choosing a method that is inappropriate for a given time series. To overcome such a problem, distinct ensemble techniques...

A choice of bilevel linear programming solving parameters: factoraggregation approach

Pavels Orlovs, Olga Montvida, Svetlana Asmuss
Our paper deals with the problem of choosing correct parameters for the bilevel linear programming solving algorithm proposed by M. Sakawa and I.~Nishizaki. We suggest an approach based on factoraggregation, which is a specially designed general aggregation operator. The idea of factoraggregation arises...

Hellinger distance for fuzzy measures

Vicenc Torra, Yasuo Narukawa, Michio Sugeno, Michael Carlson
Hellinger distance is a distance between two additive measures defined in terms of the Radon-Nikodym derivative of these two measures. This measure proposed in 1909 has been used in a large variety of contexts. In this paper we define an analogous measure for fuzzy measures. We discuss them for distorted...

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...

About t-norms on type-2 fuzzy sets

Pablo Hernández, Susana Cubillo, Carmen Torres
Walker et al. ([19], [20]) defined two families of binary operations on M (set of functions of [0,1] in [0,1]), and they determined that, under certain conditions, those operations are t-norms (triangular norm) or t-conorms on L (all the normal and convex functions of M). We define binary operations...

Fuzzy implications satisfying convexity relations

Mirko Navara
It is an open question whether a non-trivial convex combination of triangular norms (resp. conorms) can be a triangular norm (resp. conorm). We investigate the analogous question for S-implications and R-implications.

Tomonoid extensions: the key for the construction of t-norms

Thomas Vetterlein
Triangular norms, or t-norms for short, play an important role for the semantics of fuzzy logics. Although an enormous number of examples and a remarkable number of construction methods for this kind of operation has been established, a uniform approach is still outstanding. This paper is devoted to...

Determination of regional variants in the versification of Estonian folksongs using an interpretable fuzzy rule-based classifier

Andri Riid, Mari Sarv
In this paper, a method of hierarchical clustering and a selection of fuzzy classification algorithms are applied successively to the data set that contains measured characteristics of folk verses collected from 104 historical parishes of Estonia. The aim of the study is to detect the groups of parishes...

Exploring Paraconsistency in Degree-Preserving Fuzzy Logics

Rodolfo Ertola, Francesc Esteva, Tommaso Flaminio, Lluis Godo, Carles Noguera
Paraconsistent logics are specially tailored to deal with inconsistency, while fuzzy logics primarily deal with graded truth and vagueness. In the last decade, mathematical fuzzy logic has been developed as a discipline studying formal many-valued systems underlying fuzzy logic in narrow sense. In this...