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      • Open Access Article

        1 - Robust Persian Isolated Digit Recognition Based on LSTM and Speech Spectral Features
        شیما طبیبیان
        One of the challenges of isolated Persian digit recognition is similar pronunciation of some digits such as "zero and three", "nine and two" and "five, seven and eight". This challenge leads to the high substitution errors and reduces the recognition accuracy. In this p More
        One of the challenges of isolated Persian digit recognition is similar pronunciation of some digits such as "zero and three", "nine and two" and "five, seven and eight". This challenge leads to the high substitution errors and reduces the recognition accuracy. In this paper, a combined solution based on short-term memory (LSTM) and hidden Markov model (HMM) is proposed to solve the mentioned challenge. The proposed approach increases the recognition rate of Persian digits on average 2 percent and in the best case 8 percent in comparison to the HMM-based approach. In the following of this work, due to the intensification of the mentioned challenge in noisy conditions, the robust recognition of Persian digits with similar pronunciation was considered. In order to increase the robustness of the LSTM-based recognizer, robust features extracted from the speech spectrum such as spectral entropy, burst degree, bisector frequency, spectral flatness, first formant and autocorrelation-based zero crossing rate were used. Using these features, while reducing the number of features for recognizing similar Persian digits from 39 coefficients to a maximum of 4 and a minimum of 1 coefficient, on average improved the robustness of the isolated digit recognizer in different noisy conditions (30 different situations resulting from five noise types of white, pink, babble, factory and car noises and six signal-to-noise ratios of -5, 0, 5, 10, 15 and 20 decibels) by 10%, 13%, 15% and 13% compared to the HMM-based, LSTM-based, deep belief network-based recognizers with Mel-Cepstrum coefficients and a convolutional neural network-recognizer with Mel Spectrogram features. Manuscript profile
      • Open Access Article

        2 - Emotion Recognition Based on EEG Signals Using Deep Learning Based on Bi-Directional Long Short-Term Memory and Attention Mechanism
        Seyyed Abed Hosseini M. Houshmand
        This research deals with the recognition of emotions from EEG signals using deep learning based on bi-directional long short-term memory (LSTM) and attention mechanism. In this study, two SEED and DEAP databases are utilized for the emotion recognition. The SEED databas More
        This research deals with the recognition of emotions from EEG signals using deep learning based on bi-directional long short-term memory (LSTM) and attention mechanism. In this study, two SEED and DEAP databases are utilized for the emotion recognition. The SEED database includes EEG signals in 62 channels from 15 participants in three categories of positive, neutral, and negative emotions. The DEAP dataset includes EEG signals in 32 channels from 32 participants in two categories of valence and arousal. LSTM has shown its efficiency in extracting temporal information from long physiological signals. The innovations of this research include the use of a new loss function and Bayesian optimizer to find the initial learning rate. The accuracy of the proposed method for the classification of emotions in the SEED database is 96.72%. The accuracy of the proposed method for classifying emotions into two categories of valence and arousal is 94.9% and 97.1%, respectively. Finally, comparing the obtained results with recent research studies. Manuscript profile