Deep Learning

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Publications

  • 2025
    Zakia Zouaghia, Zahra Kodia, Lamjed Ben Said

    Smapf-hnna: a novel Stock Market Analysis and Prediction Framework using Hybrid Neural Network Architectures Across Major US Indices

    International Journal of Data Science and Analytics (2025): 1-37., 2025

    Résumé

    Financial markets exhibit high volatility due to various external factors, making stock price prediction a complex yet crucial task for investors and financial institutions. Accurate forecasting not only enhances decision making but also mitigates financial risks. This paper introduces SMAPF-HNNA, an advanced framework that integrates multiple neural network (NN) architectures for robust time-series analysis and stock price forecasting. The proposed approach leverages Convolutional Neural Networks (CNNs) for automatic feature extraction, followed by the application of diverse NN models, including Simple Recurrent Neural Networks (SRNNs), Long Short-Term Memory (LSTM), Bidirectional LSTM (BiLSTM), Gated Recurrent Units (GRU), Bidirectional GRU (BiGRU), and Multilayer Perceptron (MLP) for precise stock price prediction. The framework is rigorously evaluated on multiple benchmark datasets, including NYSE, S&P 500, NASDAQ, and SSE, through extensive training and testing phases. Experimental results demonstrate that the hybrid CNN-MLP model outperforms other architectures across all datasets, achieving exceptionally low error rates with five key regression metrics. The model yields mean squared error (MSE) values between 0.000031 and 0.000004, root mean squared error (RMSE) between 0.0020 and 0.0056, mean absolute error (MAE) between 0.0018 and 0.0042, mean absolute percentage error (MAPE) between 0.12% and 0.32%, and R-squared (R) values ranging from 0.9995 to 0.9999, while maintaining low computational complexity across datasets. These results highlight the potential of SMAPF-HNNA as a highly accurate and computationally efficient solution for stock market prediction, addressing the limitations of previous methods. The proposed framework offers valuable insights for researchers and practitioners, paving the way for more reliable financial market forecasting models.

    Boutheina Drira, Haykel Hamdi, Ines Ben Jaafar

    Hybrid Deep Learning Ensemble Models for Enhanced Financial Volatility Forecasting

    Second Edition IEEE Afro-Mediterranean Conference on Artificial Intelligence 2025 IEEE AMCAI IEEE AMCAI 2025, 2025

    Résumé

    this paper presents a novel ensemble
    methodology that integrates deep learning models to enhance
    the accuracy and robustness of financial volatility forecasts. By
    combining Convolutional Neural Networks (CNNs) and GRU
    networks, the proposed approach captures both spatial and
    temporal patterns in financial time series data. Empirical results
    demonstrate the superiority of this ensemble model over
    traditional forecasting methods in various financial markets.
    Keywords: Volatility Forecasting, Deep Learning, Ensemble
    Modeling, CNN, GRU, Financial Time Series

    Hana Mechria, Khaled Hassine, Mohamed Salah Gouider

    Mammogram images denoising based on deep convolutional neural network

    Imapct Factor 2024: 3.6, 2025

    Résumé

    Mammogram images are subject to various types of noise, which restricts the analysis of images and diagnosis. Mammogram image denoising is very important to improve image quality and to make the segmentation and classification results more correct. In this work, we propose a Deep Convolutional Neural Network (DCNN) to denoise the mammogram images in order to improve the image quality by handling Gaussian, Speckle, Poisson, and Salt and Pepper noise. The main objective of this study is to remove different types of noises from mammogram images and to maximize the quantity of information content in the enhanced images. We first add noise models to mammogram images and then enhance the image by removing the noise using DCNN. Furthermore, we compare our results with state-of-the-art denoising methods, such as the Adaptive Median filter, Wiener filter, Gaussian filter, Median filter, and Mean. Three datasets have been used, including Digital Database for Screening Mammography (DDSM), mini-Mammographic Image Analysis Society (mini-MIAS), and a local Tunisian dataset. The experimental results show that DCNN has a better denoising performance than the other methods, with an average PSNR range of 46.0-51.83 dB and an average SSIM range of 0.988-99.83, which may suggest its adaptability to different models of noise.

  • Zakia Zouaghia, Zahra Kodia, Lamjed Ben Said

    A novel AutoCNN model for stock market index prediction

    Journal of Telecommunications and the Digital Economy, 12(1), 612-636., 2024

    Résumé

    Stock markets have an important impact on economic growth of countries. The prediction
    of stock market indexes has been a complex task for last years. Indeed, many researches and financial analysts are highly interested in the research area of stock market prediction. In this paper, we propose a novel framework, titled AutoCNN based on artificial intelligence techniques, to predict future stock market indexes. AutoCNN is composed mainly of three stages: (1) CNN for Automatic Feature Extraction, (2) The Halving Grid Search algorithm is combined to CNN model for stock indexes prediction and (3) Evaluation and recommendation. To validate our AutoCNN, we conduct experiments on two financial datasets that are extracted in the period between 2018 and 2023, which includes several events such as economic, health and geopolitical international crises. The performance of AutoCNN model is quantified using various metrics. It is benchmarked against different models and it proves strong prediction abilities. AutoCNN contributes to emerging technologies and innovation in the financial sector by automating decision-making, leveraging advanced pattern recognition, and enhancing the overall decision support system for investors in the digital economy.

  • Zakia Zouaghia, Zahra Kodia, Lamjed Ben Said

    Hybrid machine learning model for predicting NASDAQ composite index

    2023 International Symposium on Networks, Computers and Communications (ISNCC), Doha, Qatar, 2023, pp. 1-6, 2023

    Résumé

    Financial markets are dynamic and open systems. They are subject to the influence of environmental changes. For this reason, predicting stock market prices is a difficult task for investors due to the volatility of the financial stock markets nature. Stock market forecasting leads investors to make decisions with more confidence based on the prediction of stock market price behavior. Indeed, a lot of analysts are greatly focused in the research domain of stock market prediction. Generally, the stock market prediction tools are categorized into two types of algorithms: (1) linear models like Auto Regressive (AR), Moving Average (MA), Auto-Regressive Integrated Moving Average (ARIMA), and (2) non-linear models like Autoregressive Conditionally Heteroscedastic (ARCH), Generalized Autoregressive Conditional Heteroskedasticity (GARCH) and recently Neural Network (NN)). This paper aspires to crucially predict the stock index movement for National Association of Securities Dealers Automated Quotations (NASDAQ) based on deep learning networks. We propose a hybrid stock price prediction model using Convolutional Neural Network (CNN) for feature selection and Neural Network models to perform the task of prediction. To evaluate the performance of the proposed models, we use five regression evaluation metrics: Root Mean Square Error (RMSE), Mean Square Error (MSE), Mean Absolute Error (MAE), Mean Absolute Percentage Error (MAPE) and R-Square (R2), and the Execution Time (ET) metric to calculate the necessary time for running each hybrid model. The results reveal that error rates in the CNN-BGRU model are found to be lower compared to CNN-GRU, CNN-LSTM, CNN-BLSTM and the the existing hybrid models. This research work produces a practical experience for decision makers on financial time series data.

    Wiem Ben Ghozzi, Abir Chaabani, Zahra Kodia, Lamjed Ben Said

    DeepCNN-DTI: A Deep Learning Model for Detecting Drug-Target Interactions

    International Conference on Control Decision and Information Technology Codit’9, Rome, 2023

    Résumé

    Drug target interaction is an important area of drug discovery, development, and repositioning. Knowing that in vitro experiments are time-consuming and computationally expensive, the development of an efficient predictive model is a promising challenge for Drug-Target Interactions (DTIs) prediction. Motivated by this problem, we propose in this paper a new prediction model called DeepCNN-DTI to efficiently solve such complex real-world activities. The main motivation behind this work is to explore the advantages of a deep learning strategy with feature extraction techniques, resulting in an advanced model that effectively captures the complex relationships between drug molecules and target proteins for accurate DTIs prediction. Experimental results generated based on a set of data in terms of accuracy, precision, sensitivity, specificity, and F1-score demonstrate the superiority of the model compared to other competing learning strategies.

  • Hana Mechria, Khaled Hassine, Mohamed Salah Gouider

    Effect of Denoising on Performance of Deep Convolutional Neural Network For Mammogram Images Classification

    KES, 2022

    Résumé

    Digital mammograms are an important imaging modality for breast cancer screening and diagnosis. Several types of noise appear in mammograms and make the job of detecting breast cancer even more challenging due to missing details in the information of the image.
    In this study, we analyze the effect of mammogram images quality on the performance of the Deep Convolutional Neural Network on a mammogram images classification task. Thus, our objective is to show how the classification accuracy varies with the application of a denoising step.
    Indeed, we investigated two different approaches to breast cancer detection. The first is the classification of the original mammo-gram images without being denoised, and the second is the classification of mammogram images that are denoised using a Deep Convolutional Neural Network, Wiener filter and Median filter. Therefore, the mammogram images are first denoised using each of the three denoising methods and then, classified into two classes: cancer and normal, using AlexNet, a pre-trained Deep Convo-lutional Neural Network in order to show whether the denoising method used is effective when grafted onto a Deep Convolutional Neural Network by measuring accuracy, sensitivity, and specificity.
    Interesting results are achieved where the DCNN denoising step improved the Deep Convolutional Neural Network classification task with an increase of 3.47% for overall accuracy, 5.34% for overall specificity, and 0.56% for overall sensitivity.
  • Hana Mechria, Mohamed Salah Gouider, Khaled Hassine

    Breast Cancer Detection using Deep Convolutional Neural Network

    ICAART, 2019

    Résumé

    Deep Convolutional Neural Network (DCNN) is considered as a popular and powerful deep learning algorithm in image classification. However, there are not many DCNN applications used in medical imaging, because large dataset for medical images is not always available. In this paper, we present two DCNN architectures, a shallow DCNN and a pre-trained DCNN model: AlexNet, to detect breast cancer from 8000 mammographic images extracted from the Digital Database for Screening Mammography. In order to validate the performance of DCNN in breast cancer detection using a big data , we carried out a comparative study with a second deep learning algorithm Stacked AutoEncoders (SAE) in terms accuracy, sensitivity and specificity. The DCNN method achieved the best results with 89.23% of accuracy, 91.11% of sensitivity and 87.75% of specificity.