Dragan Šaletić - Academia.edu (original) (raw)
Papers by Dragan Šaletić
Interdisciplinary Description of Complex Systems, Dec 31, 2022
The article deals with mathematical formalism of the process of combining several inputs into a s... more The article deals with mathematical formalism of the process of combining several inputs into a single output in fuzzy inteligent systems, the process known as aggregation. We are interested in logic aggregation operators. Such aggregators are present in most decision problems and in fuzzy expert systems. Fuzzy inteligent systems are equipped with aggregation operators (aggregators) with which reasoning models adapt well to human reasoning. A brief overview of the field of fuzzy aggregators is given. Attention is devoted to so called graded logic aggregators.. The role of fuzzy agregators in modelling reasoning and the way they are chosen in modelling are pointed out. The conclusions are given and research in the field is pointed out.
The data driven procedure for determining the optimal number of expert rules in a fuzzy knowledge... more The data driven procedure for determining the optimal number of expert rules in a fuzzy knowledge base of Takagi-Sugeno type is considered. The procedure is based on the Klawonn-Kruse clustering of numerical samplesa training set of the unknown function to be approximated using Takagi-Sugeno fuzzy model.
This paper gives an overview and considers impacts of some theories developed around uncertainty ... more This paper gives an overview and considers impacts of some theories developed around uncertainty representation paradigms, theory of neural networks and of evolutive computing on development of computing systems. Possible further development of soft computing and impacts of that development on the development of computing systems in general, is considered.
In the paper a software implementation of fuzzy decision-making in medicine is described. Known m... more In the paper a software implementation of fuzzy decision-making in medicine is described. Known models of fuzzy multi-criteria decision making are applied in two situations: the first, with all features of the same importance and without interaction between criteria, and the second, with interacting criteria. The practical usage of both approaches is shown in a medical application in determining the
Interval type-2 fuzzy sets are used to deal with the uncertain information present when more than... more Interval type-2 fuzzy sets are used to deal with the uncertain information present when more than one fuzzy observation can be made about the same entity. They found numerous applications in engineering recommendation systems, fuzzy control and modeling, pattern recognition and other. The paper presents a novel approach for generalizing weighted averages on purpose of processing uncertainty expressible by trapezoidal interval type-2 fuzzy sets. A family of new aggregation operators is presented, that can process data types specific for perceptual computing, and thus can be used as an engine for computing with words. It has time complexity θ(n). Some software realization details are discussed. The new engine family has been compared to novel weighted averages both analytically and empirically. Their similarities and differences are pointed out and rationalized. It has been discussed how simplified versions of the new engine resemble to some known type-reduction algorithms. Conclusions and open questions are summarized.
... Also the similarities between the alternatives are being computed. In [2] and [5] the usage o... more ... Also the similarities between the alternatives are being computed. In [2] and [5] the usage of Jaccard similarity for this is proposed: ( ) ( ) BAfBAf BA smJ ∪ ∩ = ), 10) ... TABLE II. RESULTS OF PERFORMED TESTS A B C smJ(A, B) smJ(A, C) smJ(B, C) ...
The paper considers the general fuzzy controllers design problem from a stability viewpoint. A co... more The paper considers the general fuzzy controllers design problem from a stability viewpoint. A control surface of this kind of expert systems is considered. A kind of inverted pendulum system is described. The fuzzy controller design approach is proposed. Conclusions are given and possibilities for further work are pointed out.
The object of the paper is the determination of the severity of respiratory distress of a patient... more The object of the paper is the determination of the severity of respiratory distress of a patient in an intensive care unit using fuzzy sets theory. The determination of the degree of respiratory distress is of extreme clinical relevance. In [1] the proposition is given to treat the problem by the theory of fuzzy sets and the computer implementation of the model is considered. The problem is modeled as a fuzzy multicriteria decision-making one. In this paper the use of fuzzy measures, and of corresponding Choquet integral are considered in order to get improvement of results from [1]. The improvement is due to the fact that the application of fuzzy measures can take into account the interaction between the criteria.The results are given and the directions for possible further work are pointed out.
International Journal of Medical Informatics, Sep 1, 2001
This paper proposes to apply the theory of fuzzy sets in determining the severity of respiratory ... more This paper proposes to apply the theory of fuzzy sets in determining the severity of respiratory distress of a patient in an intensive care unit. The problem is modelled as a fuzzy multicriteria decision-making one. Theoretical approaches to the situation are considered. The proposed fuzzy selection method, based on the usage of the fuzzy intervals, is described. An example of determining the severity of respiratory distress is used to illustrate the presentation. Computer implementation of the model is considered, and the directions for possible further work are pointed out.
Yugoslav Journal of Operations Research, 2010
In the paper the fuzzy extension of the Analytic Hierarchy Process (AHP) based on fuzzy numbers, ... more In the paper the fuzzy extension of the Analytic Hierarchy Process (AHP) based on fuzzy numbers, and its application in solving a practical problem, are considered. The paper advocates the use of contradictory test to check the fuzzy user preferences during fuzzy AHP decision-making process. We also propose consistency check and deriving priorities from inconsistent fuzzy judgment matrices to be included in the process, in order to check if the fuzzy approach can be applied in the AHP for the problem considered. An aggregation of local priorities obtained at different levels into composite global priorities for the alternatives based on weighted-sum method is also discussed. The contradictory fuzzy judgment matrix is analyzed. Our theoretical consideration has been verified by an application of commercially available Super Decisions program (developed for solving multi-criteria optimization problems using AHP approach) on the problem previously treated in the literature. The obtained results are compared with those from the literature. The conclusions are given and the possibilities for further work in the field are pointed out.
This paper gives an overview and considers impacts of some theories developed around uncertainty ... more This paper gives an overview and considers impacts of some theories developed around uncertainty representation paradigms, theory of neural networks and of evolutive computing on development of computing systems. Possible further development of soft computing and impacts of that development on the development of computing systems in general, is considered.
EUROCON 2005 - The International Conference on "Computer as a Tool", 2005
The data driven procedure for determining the optimal number of expert rules in a fuzzy knowledge... more The data driven procedure for determining the optimal number of expert rules in a fuzzy knowledge base of Takagi-Sugeno type is considered. The procedure is based on the Klawonn-Kruse clustering of numerical samplesa training set of the unknown function to be approximated using Takagi-Sugeno fuzzy model.
2006 8th Seminar on Neural Network Applications in Electrical Engineering, 2006
The purpose of this paper is to give the results of research analysis of basic defuzzification te... more The purpose of this paper is to give the results of research analysis of basic defuzzification techniques and to point out to possible constraints in application of these techniques. The defuzzification process is present in a fuzzy system when an output fuzzy set should be mapped to a crisped value. Features are given which is the base for a defuzzification technique comparison. Techniques are classified into several groups. The analysis of defuzzification techniques is given, as well as their comparison on the base of given features. The results from computer experiments suggest constrained domain of applicability of defuzzification techniques. Suggestions about applicability of techniques in specified applications are given
2009 7th International Symposium on Intelligent Systems and Informatics, 2009
This paper describes the development of a prototype fuzzy sets based expert system for financial ... more This paper describes the development of a prototype fuzzy sets based expert system for financial applications, an assistant to a human expert. Computer implementation of the model is considered, and directions for possible further work are pointed out. The advantages of the approach are discussed, as well as the possibilities for more complex models in the field, based on type-2 fuzzy sets. Conclusions are given.
Interdisciplinary Description of Complex Systems, Dec 31, 2022
The article deals with mathematical formalism of the process of combining several inputs into a s... more The article deals with mathematical formalism of the process of combining several inputs into a single output in fuzzy inteligent systems, the process known as aggregation. We are interested in logic aggregation operators. Such aggregators are present in most decision problems and in fuzzy expert systems. Fuzzy inteligent systems are equipped with aggregation operators (aggregators) with which reasoning models adapt well to human reasoning. A brief overview of the field of fuzzy aggregators is given. Attention is devoted to so called graded logic aggregators.. The role of fuzzy agregators in modelling reasoning and the way they are chosen in modelling are pointed out. The conclusions are given and research in the field is pointed out.
The data driven procedure for determining the optimal number of expert rules in a fuzzy knowledge... more The data driven procedure for determining the optimal number of expert rules in a fuzzy knowledge base of Takagi-Sugeno type is considered. The procedure is based on the Klawonn-Kruse clustering of numerical samplesa training set of the unknown function to be approximated using Takagi-Sugeno fuzzy model.
This paper gives an overview and considers impacts of some theories developed around uncertainty ... more This paper gives an overview and considers impacts of some theories developed around uncertainty representation paradigms, theory of neural networks and of evolutive computing on development of computing systems. Possible further development of soft computing and impacts of that development on the development of computing systems in general, is considered.
In the paper a software implementation of fuzzy decision-making in medicine is described. Known m... more In the paper a software implementation of fuzzy decision-making in medicine is described. Known models of fuzzy multi-criteria decision making are applied in two situations: the first, with all features of the same importance and without interaction between criteria, and the second, with interacting criteria. The practical usage of both approaches is shown in a medical application in determining the
Interval type-2 fuzzy sets are used to deal with the uncertain information present when more than... more Interval type-2 fuzzy sets are used to deal with the uncertain information present when more than one fuzzy observation can be made about the same entity. They found numerous applications in engineering recommendation systems, fuzzy control and modeling, pattern recognition and other. The paper presents a novel approach for generalizing weighted averages on purpose of processing uncertainty expressible by trapezoidal interval type-2 fuzzy sets. A family of new aggregation operators is presented, that can process data types specific for perceptual computing, and thus can be used as an engine for computing with words. It has time complexity θ(n). Some software realization details are discussed. The new engine family has been compared to novel weighted averages both analytically and empirically. Their similarities and differences are pointed out and rationalized. It has been discussed how simplified versions of the new engine resemble to some known type-reduction algorithms. Conclusions and open questions are summarized.
... Also the similarities between the alternatives are being computed. In [2] and [5] the usage o... more ... Also the similarities between the alternatives are being computed. In [2] and [5] the usage of Jaccard similarity for this is proposed: ( ) ( ) BAfBAf BA smJ ∪ ∩ = ), 10) ... TABLE II. RESULTS OF PERFORMED TESTS A B C smJ(A, B) smJ(A, C) smJ(B, C) ...
The paper considers the general fuzzy controllers design problem from a stability viewpoint. A co... more The paper considers the general fuzzy controllers design problem from a stability viewpoint. A control surface of this kind of expert systems is considered. A kind of inverted pendulum system is described. The fuzzy controller design approach is proposed. Conclusions are given and possibilities for further work are pointed out.
The object of the paper is the determination of the severity of respiratory distress of a patient... more The object of the paper is the determination of the severity of respiratory distress of a patient in an intensive care unit using fuzzy sets theory. The determination of the degree of respiratory distress is of extreme clinical relevance. In [1] the proposition is given to treat the problem by the theory of fuzzy sets and the computer implementation of the model is considered. The problem is modeled as a fuzzy multicriteria decision-making one. In this paper the use of fuzzy measures, and of corresponding Choquet integral are considered in order to get improvement of results from [1]. The improvement is due to the fact that the application of fuzzy measures can take into account the interaction between the criteria.The results are given and the directions for possible further work are pointed out.
International Journal of Medical Informatics, Sep 1, 2001
This paper proposes to apply the theory of fuzzy sets in determining the severity of respiratory ... more This paper proposes to apply the theory of fuzzy sets in determining the severity of respiratory distress of a patient in an intensive care unit. The problem is modelled as a fuzzy multicriteria decision-making one. Theoretical approaches to the situation are considered. The proposed fuzzy selection method, based on the usage of the fuzzy intervals, is described. An example of determining the severity of respiratory distress is used to illustrate the presentation. Computer implementation of the model is considered, and the directions for possible further work are pointed out.
Yugoslav Journal of Operations Research, 2010
In the paper the fuzzy extension of the Analytic Hierarchy Process (AHP) based on fuzzy numbers, ... more In the paper the fuzzy extension of the Analytic Hierarchy Process (AHP) based on fuzzy numbers, and its application in solving a practical problem, are considered. The paper advocates the use of contradictory test to check the fuzzy user preferences during fuzzy AHP decision-making process. We also propose consistency check and deriving priorities from inconsistent fuzzy judgment matrices to be included in the process, in order to check if the fuzzy approach can be applied in the AHP for the problem considered. An aggregation of local priorities obtained at different levels into composite global priorities for the alternatives based on weighted-sum method is also discussed. The contradictory fuzzy judgment matrix is analyzed. Our theoretical consideration has been verified by an application of commercially available Super Decisions program (developed for solving multi-criteria optimization problems using AHP approach) on the problem previously treated in the literature. The obtained results are compared with those from the literature. The conclusions are given and the possibilities for further work in the field are pointed out.
This paper gives an overview and considers impacts of some theories developed around uncertainty ... more This paper gives an overview and considers impacts of some theories developed around uncertainty representation paradigms, theory of neural networks and of evolutive computing on development of computing systems. Possible further development of soft computing and impacts of that development on the development of computing systems in general, is considered.
EUROCON 2005 - The International Conference on "Computer as a Tool", 2005
The data driven procedure for determining the optimal number of expert rules in a fuzzy knowledge... more The data driven procedure for determining the optimal number of expert rules in a fuzzy knowledge base of Takagi-Sugeno type is considered. The procedure is based on the Klawonn-Kruse clustering of numerical samplesa training set of the unknown function to be approximated using Takagi-Sugeno fuzzy model.
2006 8th Seminar on Neural Network Applications in Electrical Engineering, 2006
The purpose of this paper is to give the results of research analysis of basic defuzzification te... more The purpose of this paper is to give the results of research analysis of basic defuzzification techniques and to point out to possible constraints in application of these techniques. The defuzzification process is present in a fuzzy system when an output fuzzy set should be mapped to a crisped value. Features are given which is the base for a defuzzification technique comparison. Techniques are classified into several groups. The analysis of defuzzification techniques is given, as well as their comparison on the base of given features. The results from computer experiments suggest constrained domain of applicability of defuzzification techniques. Suggestions about applicability of techniques in specified applications are given
2009 7th International Symposium on Intelligent Systems and Informatics, 2009
This paper describes the development of a prototype fuzzy sets based expert system for financial ... more This paper describes the development of a prototype fuzzy sets based expert system for financial applications, an assistant to a human expert. Computer implementation of the model is considered, and directions for possible further work are pointed out. The advantages of the approach are discussed, as well as the possibilities for more complex models in the field, based on type-2 fuzzy sets. Conclusions are given.