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Genetic fuzzy logic based system for arrhythmia classification  107


              Radosav, 2018). The results indicate that convolutional neural networks are
              the most widely represented (Parvaneh et al., 2019).
                 In addition, the FLC that mimics experts to generate a suitable control
              action for a particular system has been largely integrated in DSS process. By
              referring to the expert knowledge, the FLC is mainly used to overcome the
              uncertainty and vagueness and to involve approximate reasoning for
              decision-making tasks. In the medical sector, and more particularly for clas-
              sifying ECG signals, numerous works based on the FLC approach have been
              developed and evaluated (Krishnaiah et al., 2016). However, its configura-
              tion is still a challenging task. Indeed, the FLC performances depend on the
              adjustment of the membership functions parameters and its rule base. To
              overcome this problem, a number of hybrid approaches were offered in
              several research studies, such as fuzzy clustering techniques and fuzzy evo-
              lutionary algorithms (Rathi and Narasimhan, 2017).
                 Thus, in this study, a fuzzy genetic-based system for cardiac arrhythmia
              classification is investigated. It is applied to classify the MIT-BIH Arrhyth-
              mia Database recordings into five arrhythmia types: (1) Normal Sinus
              Rhythm (NSR), (2) Premature Ventricular Contraction (PVC), (3) Left
              Bundle Branch Block (LBBB), (4) Right Bundle Branch Block (RBBB)
              and (5) Paced beats (P) (Silva and Moody, 2014). Previously, we have used
              the neural networks for this task (Lassoued and Ketata, 2018c). However, we
              concluded that it is usually difficult to select the more appropriate neural net-
              work structure and to interpret its results. Accordingly, the proposed based
              system consists of a FLC whose membership parameters and rules number
              are adjusted by a GA. This system has to define the correct arrhythmia type
              for a previously unknown sample. Then, a comparison study between the
              obtained accuracies before and after the genetic optimization will be ana-
              lyzed. Simultaneously, in order to access the efficiency of this study, a second
              comparison study between neural network approaches and the proposed
              FLC will be done.
                 This chapter is organized as follows. Section 2 describes the proposed
              arrhythmia classification methodology. Section 3 details the experiments
              and results, and the final section provides a conclusion.


              2 Methodology

              In this section, we describe the suggested arrhythmia classification method-
              ology, which consists of a hybrid system between a FLC and GA. As it is
              described in Fig. 1, the FLC uses a pre-processing block to filter the original
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