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Accurate and early detection of causes of pneumonia is important for implementing fast treatment and preventive strategies, reducing the burden of infections, and establishing more effective ways of interventions. After the outbreak of COVID-19, the new cases of pneumonia and conditions of breathing problems called acute respiratory distress syndrome have increased. Chest radiography, known as CXR or simply X-ray has become a significant source to diagnose COVID-19-infected pneumonia in designated institutions and hospitals. It is essential to develop automated computer systems to assist doctors and medical experts to diagnose pneumonia in a fast and reliable manner. In this work, we propose a deep learning (DL)-based computer-aided diagnosis system for rapid and easy detection of pneumonia using X-ray images. To improve classification accuracy and faster conversion of the models, we employ transfer learning and parallel computing techniques using well-known DL models such as VGG19 and ResNet50. Experiments are conducted on the large COVID-QU-Ex dataset of X-ray images with three classes, such as COVID-19-infected pneumonia, non-COVID-19 infections (other viral and bacterial pneumonia), and normal (uninfected) images. The proposed model outperformed compared methodologies, achieving an average classification accuracy of 96.6%. Experimental results demonstrate that the proposed method is effective in diagnosing pneumonia using X-ray images.

Deep neural networks (DNN) have proven to be efficient in computer vision and data classification with an increasing number of successful applications. Time series classification (TSC) has been one of the challenging problems in data mining in the last decade, and significant research has been proposed with various solutions, including algorithm-based approaches as well as machine and deep learning approaches. This paper focuses on combining the two well-known deep learning techniques, namely the Inception module and the Fully Convolutional Network. The proposed method proved to be more efficient than the previous state-of-the-art InceptionTime method. We tested our model on the univariate TSC benchmark (the UCR/UEA archive), which includes 85 time-series datasets, and proved that our network outperforms the InceptionTime in terms of the training time and overall accuracy on the UCR archive.

Breast cancer screening and detection using high-resolution mammographic images have always been a difficult task in computer vision due to the presence of very small yet clinically significant abnormal growths in breast masses. The size difference between such masses and the overall mammogram image as well as difficulty in distinguishing intra-class features of the Breast Imaging Reporting and Database System (BI-RADS) categories creates challenges for accurate diagnosis. To obtain near-optimal results, object detection models should be improved by directly focusing on breast cancer detection. In this work, we propose a new two-stage deep learning method. In the first stage, the breast area is extracted from the mammogram and small square patches are generated to narrow down the region of interest (RoI). In the second stage, breast masses are detected and classified into BI-RADS categories. To improve the classification accuracy for intra-classes, we design an effective tumor classification model and combine its results with the detection model’s classification scores. Experiments conducted on the newly collected high-resolution mammography dataset demonstrate our two-stage method outperforms the original Faster R-CNN model by improving mean average precision (mAP) from 0.85 to 0.94. In addition, comparisons with existing works on a popular INbreast dataset validate the performance of our two-stage model.

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Existing inefficient traffic signal plans are causing traffic congestions in many urban areas. In recent years, many deep reinforcement learning (RL) methods have been proposed to control traffic signals in real-time by interacting with the environment. However, most of existing state-of-the-art RL methods use complex state definition and reward functions and/or neglect the real-world constraints such as cyclic phase order and minimum/maximum duration for each traffic phase. These issues make existing methods infeasible to implement for real-world applications. In this paper, we propose an RL-based multi-intersection traffic light control model with a simple yet effective combination of state, reward, and action definitions. The proposed model uses a novel pressure method called Biased Pressure (BP). We use a state-of-the-art advantage actor-critic learning mechanism in our model. Due to the decentralized nature of our state, reward, and action definitions, we achieve a scalable model. The performance of the proposed method is compared with related methods using both synthetic and real-world datasets. Experimental results show that our method outperforms the existing cyclic phase control methods with a significant margin in terms of throughput and average travel time. Moreover, we conduct ablation studies to justify the superiority of the BP method over the existing pressure methods.

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