A novel approach for the reconstruction of microbarom soundscapes

<p>A comparison is made between in-situ infrasound recordings in the microbarom band and simulations using a microbarom source model. The recordings are obtained by the 'Infrasound-Logger' (IL), a miniature sensor deployed as a biologger near the Crozet Islands in January 2020. The sensors provide barometric and differential pressure observations obtained directly above the sea surface. As the full wavefield consists of multiple spatially distributed sources, a method is introduced to appropriately account for all microbarom source contributions surrounding the IL. In this method, the modeled source field is coupled to a semi-empirical propagation model to take into account the propagation losses from source to receiver. Although the method relies on several assumptions, a good agreement can be observed: the reconstructed soundscape is found to be within +- 5 dB for 80% of the measurements in the microbarom band of 0.1-0.3 Hz. The reconstruction of microbarom soundscapes is essential for understanding the ambient infrasonic noise field and benefits several applications that include atmospheric remote sensing, natural hazard monitoring as well as verification of the Comprehensive Nuclear-Test-Ban Treaty (CTBT).</p>

Performance Analysis of Sub-GHz System for IoT Applications

This article reports a sub-GHz, 868MHz, battery operated miniature sensor node with a fabricated helical Printed Circuit Board (PCB) and a third party whip antenna for Internet of Things (IoT) applications. CC1310 System on Chip (SoC), a sub-GHz family wireless microcontroller, is used to design the system. A HDC 1050 temperature and humidity sensor is interfaced with the microcontroller. The system has the desirable benefits of being small and inexpensive, long battery life and capable of long transmission range. The path loss exponent is calculated from Received Signal Strength Indicator (RSSI) values in two environments - free space and across concrete obstructions. A wireless sensor network is incorporated into a cloud platform for real time monitoring, and web application has been developed for data display and analysis. To validate the proposed IoT system, the measured data is compared with an independent meteorological data set from the Indian Meteorological Department, Cyclone Warning Centre, Visakhapatnam.

Real-Time Mobile-Based Electrocardiogram System for Remote Monitoring of Patients with Cardiac Arrhythmias

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.