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Öğe Classification of EEG Records for the Cursor Movement with the Convolutional Neural Network(IEEE, 2018) Turk, Omer; Ozerdem, Mehmet Sirac; Ozyildirim, BM; Yildirim, TNowadays, very successful results are obtained with deep learning architectures which can be applied to many fields. Because of the high performances it provides in many areas, deep learning has come to a central position in machine learning and pattern recognition. In this study, electroencephalogram (EEG) signals related to up and down cursor movements were represented as image pattern by using obtained approximation coefficients after wavelet transform. The Obtained image patterns were classified by applying Convolutional Neural Network. In this study, EEG records related to cursor movements were classified and classification accuracy was obtained as 88.13%.Öğe Classification of Mental Task EEG Records Using Hjorth Parameters(IEEE, 2017) Turk, Omer; Seker, Mesut; Akpolat, Veysi; Ozerdem, Mchmet SiracThe effects of mental activities on brain dynamics is the main field that studied for a long time, but the results of studies have not reached the desired level. The aim of present study was to classify the mental task EEG records by using Hjorth parameters. hi this study, EEG signals that recorded from 9 subjects were used. EEG signals were recorded by applying a experimental paradigm which contains five stimuli related to different mental task. These stimuli are defined as condition word mental subtraction spatial navigation right hand motor imagery and feet motor imagery Wavelet packet transform was used to obtain sub bands of EEC signals. Statistical parameters that consist of mobility, complexity and Mahalanobis distance were applied to sub-bands. Feature vectors were classified by using artificial neural network. When classification performances related to mental activities were examined, the best classification accuracy was obtained as nearly 80% for 'condition word - mental subtraction', ('spatial navigation feet motor imagery;' and 'spatial navigation - condition word'. The lowest classification accuracy was obtained for 'mental subtraction - right hand motor imagery,', 'condition word - right hand motor imagery' and 'spatial navigation right hand motor imagery'. The classification accuracies related to all stimuli that classifed among themselves were obtained as 77,61%.Öğe Determination Of Changes in Frequencies of EEG Signal in Eyes Open/Closed Duration(IEEE, 2015) Turk, Omer; Ozerdem, Mehmet SiracIn this study, the changes of the power spectral density (PSD) in the EEG data during eyes-closed and eyes-open states were analyzed. In the analysis, the interval of dominant frequencies was roughly determined with different approaches. The EEG signal is separated into sub bands with wavelet transform (WT). The Welch method which is the one of the classical methods was used for PSD prediction and the Burg and Yule-Walker parametric methods were used also for PSD prediction of the EEG signal. It was observed that the alpha rhythm is dominant band in the eyes closed state compared to eyes open state.Öğe MENTAL ACTIVITY DETECTION FROM EEG RECORDS USING LOCAL BINARY PATTERN METHOD(IEEE, 2017) Turk, Omer; Ozerdem, Mehmet SiracElectroencephalogram signals are widely used in the detection of different activities but not in the desired level. In this study with this motivation, it is aimed to obtain the attributes by using the Local Bilinear Pattern (LBP) method of EEG records for various mental activities and to classify these features by k-Nearest Neighbor (k-NN) method. The binary classification performance of these EEG records containing 5 mental tasks was evaluated. In addition, in order to evaluate classification performance, confusion matrix was used as model performance criterion. In the study, the average of the classification performance of all participants was found as 87.38%. As a model performance criterion from the participants' classification of mental activity, accuracy was 85.03%, precision was 85.40% and sensitivity was 85.47%. So, as a result the obtained results support the literature and the applicability of the LBP method for EEG markings has been confirmed.