Concentramos nossos estudos em três grandes áreas: Pesquisa Operacional, Tomada de Decisão e Inteligência Computacional.

- métodos de programação matemática
- planejamento de experimentos, análise de sensibilidade e modelos funcionalmente orientados
- modelagem matemática de sistemas e processos
- otimização multiobjetivo
- processamento e utilização das informações qualitativas
- agregação das informações quantitativas e qualitativas
- tomada de decisão multicritério (individual e em grupo)
- esquemas de consenso
- consideração do fator de incerteza e sua superação
- alocação de recursos e construção de portfólios
- controle
*fuzzy*e sistemas especialistas - aprendizagem estatística, redes neurais,
*data mining*

P. Ekel, W. Pedrycz, and J. Pereira Jr.,
*Multicriteria Decision–Making Under Conditions of Uncertainty: A Fuzzy Set Perspective, *New York/Chichester/Brisbane, John Wiley & Sons, 2020

W. Pedrycz, P. Ekel, and R. Parreiras,
*Fuzzy Multicriteria Decision-Making: Models, Methods, and Applications, *New York/Chichester/Brisbane, John Wiley & Sons, 2011

M. P. Liborio, P. Ekel, A. M. C. Machado, and J. F. Abreu,
"Effect of sub-indicator weighting schemes on the spatial dependence of multidimensional phenomena,"
*Journal of Geographical Systems, *25, pp. 185-211, 2023

M. P. Liborio, A. M. A. Diniz, R.-D. Hamidreza, O. S. Martinuci, C. A. P. Silva, and P. Ekel,
"A decision framework for identifying methods to construct stable composite indicators that capture the concept of multidimensional social phenomena: the case of social exclusion,"
*Sustainability, *15, pp. 6171-6181, 2023

L. M. L. Silva, P. Ekel, D. A. G. Vieira, M. P. Liborio, and M. F. S. Vasconcelos,
"Spatial decision-making under uncertainties for supporting the prospection of sites for hybrid renewable energy generation systems,"
*Energies, *16, pp. 4880-4895, 2023

S. P. Rocha, S. M. Silva, and P. Ekel,
"Fuzzy set-based approach for grid integration and operation of ultra-fast charging electric buses,"
*International Journal of Electric Power and Energy Systems, *138, pp. 109719-109733, 2022

M. P. Liborio, J. F. Abreu, A. M. Correa, P. Ekel, O. Martinuci, and S. Laudares,
"Representing multidimensional phenomena of geographic interest: Benefit-of-the-doubt or principal component analysis?,"
*The Professional Geographer, *74, pp. 758-771, 2022

P. Ekel, P. Bernandes, G. Vale, and M. P. Liborio,
"South American business environment cost index: Reforms for Brazil,"
*International Journal of Business Environment, *13, pp. 212-234, 2022

M. P. Liborio, J. F. Abreu, O. Martinuci, P. Ekel, R. Lyrio, V. A. L. Camacho, and E. S. Melazzo,
"Uncertainty analysis applied to the representation of multidimensional social phenomena,"
*Papers in Applied Geography, *8, pp. 315-338, 2022

M. P. Liborio, J. B. Souza, S. J. F. Guimaraes, P. Ekel,
"Estimating municipal economic activity: An alternative data-based approach,"
*Remote Sensing Applications-Society and Environment, *28, pp. 100877-100892, 2022

L. R. Figuoiredo, E. Frej, G. L. Soares, and P. Ekel,
"Group decision-based construction of scenarios for multicriteria analysis in conditions of uncertainty on the basis of quantitative and qualitative information,"
*Group Decision and Negotiation, *30, pp. 665-696, 2021

W. Maia, P. Ekel, D. A. G. Vieira, E. A. Castro, M. A. D. O. Ferreira, I. M. Reis, and K. M. G. Santos,
"Evaluation of operational risk in power substations and its rational reduction on the basis of multicriteria allocating resources,"
*IEEE Access, *9, pp. 149383-149397, 2021

F. Ramalho, I. Silva, P. Ekel, C. A. P. S. Martins, P. Bernardes, and M. P. Liborio,
"Multimethod to prioritize projects evaluated in different formats,"
*MethodsX, *8, pp. 101371-101383, 2021

M. P. Liborio, P. Ekel, O. Martinuci, L. Figuoiredo, R. L. Hadad, R. Lyrio, and P. Bernardes,
"Fuzzy set based intra-urban inequality indicator,"
*Quality & Quantity, *56, pp. 667-687, 2021

E. A. Frej, P. Ekel, and A.T. Almeida,
"A benefit-to-cost ratio based approach for portfolio selection under multiple criteria with incomplete preference information,"
*Information Sciences, *545, pp. 487-498, 2021

L. M. L. Silva, P. Ekel, D. Vieira, and G. L. Soares,
"Multiattribute spatial decision-making for qualitative information processing as applied to the renewable energy generating sites prospection,"
*IEEE Access, *8, pp. 137745-137757, 2020

W. H. Saldanha, F. R. P. Arrieta, T. M. Machado-Coelho, E. D. Santos, C. B. Maia, P. Ekel, and G. L. Soares,
"Evolutionary algorithms and the preference ranking organization method for enrichment evaluations as applied to a multiobjective design of shell-and-tube heat exchangers,"
*Case Studies in Thermal Engineering, *17, pp. 100564-100570, 2020

M. P. Liborio, P. Ekel, R. Lyrio, P. Bernardes, G. L. Soares, T. M. Machado-Coelho,
"Expand or oversize? Planning internet access network in a demand growth scenario,"
*Journal of Network and Systems Management, *28, pp. 1820-1838, 2020

W. H. Saldanha, F. R. P. Arrieta, P. Ekel, T. M. Machado-Coelho, and G. L. Soares,
"Multi-criteria decision-making under uncertainty conditions of a shell-and-tube heat exchanger,"
*International Journal of Heat and Mass Transfer, *155, pp. 119716-119721, 2020

L. I. Santos, M. F. S. V. D'Angelo, L. B. Cosme, H. R. Oliveira, J. B. Mendes, and P. Ya. Ekel,
"Swarm intelligence and fuzzy sets for bed exit detection of elderly,"
*Journal of Intelligent & Fuzzy Systems, *155, pp. 119716-119721, 2020

M. P. Liborio, P. Ekel, R. Lyrio, P. Bernardes, G. L. Soares, T. M. Machado-Coelho,
"Structural equation modeling applied to internet consumption forecast in Brazil,"
*IEEE Access, *8, pp. 161816-161824, 2020

F. D. Ramalho, P. Ya. Ekel, W. Pedrycz, J. G. Pereira Jr., and G. L. Soares,
"Multicriteria decision making under conditions of uncertainty in application to multiobjective allocation of resources,"
*Information Fusion, *49, pp. 249-261, 2019

P. Ya. Ekel, A. C. Lisboa, J. G. Pereira Jr., D. A. G. Vieira, L. M. L. Silva, and M. F. S. V. D‘Angelo,
"Two-stage multicriteria georeferenced express analysis of new electric transmission line projects,"
*International Journal of Electric Power and Energy Systems, *108, pp. 415-431, 2019

M. P. Liborio, T. M. Machado-Coelho, P. Bernardes, A. M. C. Machado, P. Ekel, and G. L. Soares,
"Forecasting Internet Demand Based in Open Data - a Case Study in Brazil,"
*IEEE Access, *6, pp. 65974-65980, 2018

T. M. Machado-Coelho, A. M. C. Machado, L. Jaulin, P. Ekel, W. Pedrycz, and G. L. Soares,
"An interval space reducing method for constrained problems with particle swarm optimization,"
*Applied Soft Computing, *23, pp. 405-417, 2017

W. H. Saldanha, G. L. Soares, T. M. Machado-Coelho, E. D. Santos, and P. Ekel,
"Choosing the best evolutionary algorithm to optimize the multiobjective shell-and-tube heat exchanger design problem using PROMETHEE,"
*Applied Thermal Engineering, *127, pp. 1049-1061, 2017

P. Ekel, I. Kokshenev, R. Parreiras, W. Pedrycz, and J. Pereira Jr.,
"Multiobjective and multiattribute decision making in a fuzzy environment and their power engineering applications,"
*Information Sciences, *361-362, pp. 100-119, 2016

J. G. Pereira, P. Ya. Ekel, R. M. Palhares, and R. O. Parreiras,
"On multicriteria decision making under conditions of uncertainty,"
*Information Sciences, *324, pp. 44-59, 2015

I. Kokshenev, R. Parreiras, P. Ya. Ekel, G. B. Alves, and S. V. Menicucci,
"A Web-based Decision Support Center for Electrical Energy Companies,"
*IEEE Transactions on Fuzzy Systems, *23, pp. 16-28, 2015

P. Ekel, M. Junges, I. Kokshenev, and R. Parreiras,
"Sensitivity and functionally oriented models for power system planning, operation, and control,"
*International Journal of Electric Power and Energy Systems, *45, pp. 2846-2868, 2013

R. Parreiras, P. Ekel, and F. Bernandes Jr.,
"A dynamic consensus scheme based on a nonreciprocal fuzzy preference relation modeling,"
*Information Sciences, *211, pp. 1-17, 2012

R.O. Parreiras, P.Ya. Ekel, and D.C. Morais,
"Fuzzy set based consensus schemes for multicriteria group decision making applied to strategic planning,"
*Group Decision and Negotiation, *21, pp. 153-183, 2012

P. Ekel, I. Kokshenev, R. Palhares, R. Parreiras, F. Schuffner Neto,
"Multicriteria analysis based on constructing payoff matrices and applying methods of decision making in fuzzy environment,"
*Optimization and Engineering, *12, pp. 5-29, 2011

R. C. Berredo, P. Ya. Ekel, J. S. C. Martini, R. M. Palhares, R. O. Parreiras, and J. G. Pereira Jr.,
"Decision making in fuzzy environment and multicriteria power engineering problems,"
*International Journal of Electric Power and Energy Systems, *33, pp. 623-632, 2011

P. Ya. Ekel, J. S. C. Martini, and R. M. Palhares,
"Multicriteria analysis in decision making under information uncertainty,"
*Applied Mathematics and Computation, *200, pp. 501-516, 2008

P. Ya. Ekel, M. Menezes, and F. Schuffner Neto,
"Decision making in fuzzy environment and its application to power engineering problems,"
*Nonlinear Analysis: Hybrid Systems, *1, pp. 527-536, 2007

L. Canha, P. Ekel, J. Queiroz, and F. Schuffner Neto,
"Models and methods of decision making in fuzzy environment and their applications to power engineering problems,"
*Numerical Linear Algebra with Applications, *14, pp. 369-390, 2007

P.Ya. Ekel and F.H. Schuffner Neto,
"Algorithms of discrete optimization and their application to problems with fuzzy coefficients,"
*Information Sciences, *176, pp. 2846-2868, 2006

P. Ya. Ekel, C. A. P. S. Martins, J. G. Pereira Jr., R. M. Palhares, and L. N. Canha,
"Fuzzy set based multiobjective allocation of resources and its applications,"
*Computers and Mathematics with Applications, *52, pp. 197-210, 2006

E. A. Galperin and P. Ya. Ekel,
"Synthetic realization approach to fuzzy global optimization via gamma algorithm,"
*Mathematical and Computer Modelling, *41, pp. 1457-1468, 2005

R. C. Berredo, P. Ya. Ekel, and R. M. Palhares,
"Fuzzy preference relations in models of decision making,"
*Nonlinear Analysis: Theory, Methods and Applications, *63, pp. 735-741, 2005

P. Ya. Ekel and E. A. Galperin,
"Box-triangular multiobjective linear programs for resource allocation with application to load management and energy market problems,"
*Mathematical and Computer Modelling, *37, pp. 1-17, 2003

P. Ekel, R. Palhares, W. Araujo, M. Silva, V. Popov, A. Bondarenko, and V. Tkachenko,
"Generalized algorithms of discrete optimization and their applications,"
*International Journal of Computer Research, *12, pp. 131-140, 2003

P.Ya. Ekel,
"Fuzzy sets and models of decision making,"
*Computers & Mathematics with Applications, *44, pp. 863-875, 2002

P. Ya. Ekel,
"Methods of decision making in fuzzy environment and their applications,"
*Nonlinear Analysis: Theory, Methods and Applications, *47, pp. 979-990, 2001

P. Ekel, W. Pedrycz, and R. Schinzinger,
"A general approach to solving a wide class of fuzzy optimization problems,"
*Fuzzy Sets and Systems, *97, pp. 49-66, 1998