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This study presents an improved data augmentation technique for the classification of remote sensing (RS) scenes. The method is called Quality-based Sample Selection (QSS) data augmentation technique. It is based on generating a large number of samples using geometric transformations and then selecting the best ones based on a quality criterion. Sample images are generated online, i.e. during training of the convolutional neural network (CNN) model. For each training sample image, a few images are generated randomly using a set of geometric transformations. Then, the generated images are passed to the CNN model being trained, and the predicted probabilities are used to evaluate the quality of the images. The motivation behind this research is that we aim to augment the training set with new images that will benefit the learning of the CNN model. Therefore, an objective method to evaluate the quality of the new images is the CNN model itself. The image with the best criteria score is used to augment the training set. Several quality criteria based on the prediction probabilities of the CNN model are considered including entropy, breaking-ties and our own proposed criteria called True Label Probability (TLP). QSS is tested on five common RS scene classification datasets: UCMerced, Optimal31, RSSCN7, AID and NWPU-RS45. It has outperformed all previous methods except for one case involving NWPU-RS45 dataset. For the 10%–90% train–test split, QSS achieved 94.51, 81.72, 89.89, 94.09 and 93.98, respectively, for the mentioned datasets. While for the 20%–80% train–test split, it achieved 97.09, 88.37, 94.01, 95.71 and 94.71, respectively, for the listed datasets. Thus, this work presents a novel data augmentation method that uses data with higher quality instead of randomly selected. The paper proves experimentally that the proposed method improves the classification accuracy of RS scene classification. [ABSTRACT FROM AUTHOR]

In this study, we propose an electrocardiogram (ECG) system for the simultaneous and remote monitoring of multiple heart patients. It consists of three main components: patient, sever, and monitoring units. The patient unit uses a wearable miniature sensor that continuously measures ECG signals and sends them to a smart mobile phone via a Bluetooth connection. In the mobile device, the ECG signals can be stored, displayed on screen, and automatically transmitted to a distant server unit over the internet; the server stores ECG data from several patients. Health care stakeholders use a monitoring unit to retrieve the ECG signals of multiple patients at any time from the server for display and real-time automatic analysis. The analysis includes segmentation of the ECG signal into separate heartbeats followed by arrhythmia detection and classification. When compared to existing real-time ECG systems, where the detection of abnormalities is usually performed using simple rules, the proposed system implements a real-time classification module that is based on a support vector machine (SVM) classifier. Extensive experimental results on ECG data obtained from a TechPatientTM simulator, a real person, and 20 records from the MIT arrhythmia database are reported and discussed. [ABSTRACT FROM AUTHOR]