Digital seismo-acoustic signal processing aboard a wireless sensor array for volcano monitoring

This work describes the design and implementation of a low cost wireless sensor array utilizing digital processing to conduct autonomous real-time seismo-acoustic signal analysis of earthquakes at actively erupting volcanoes. The array consists of (1) three sensor nodes, which comprise seismic and acoustic sensors, (2) a GPS-based time synchronization node, and (3) a base receiver node, which features a communication channel for long distance telemetry. These nodes are based on the Moteiv TMote Sky wireless platform. The signal analysis accomplishes Real-time Seismic-Amplitude Measurement (RSAM) and Seismic Spectral-Amplitude Measurement (SSAM) calculations, and the extraction of triggered arrival time, event duration, intensity, and a decimated version of the triggered events for both channels. These elements are fundamental descriptors of earthquake activity. The processed data from the sensor nodes are transmitted back to the central node, where additional processing may be performed. This final information can be transmitted periodically via low bandwidth telemetry options

PERFORMANCE EVALUATION OF WIRELESS SENSOR NETWORK ROUTING PROTOCOL FOR VOLCANO ACTIVITY MONITORIN

As a country with the most volcanoes in the world, the Indonesian government must provide accurate and up-to-date information on the activity of active volcanoes. Until 2021, only 59% of mountains were directly monitored. Monitoring volcanic activity is not an easy thing to do. Visual observation alone is not enough, and instrumental comment is needed. Wireless Sensor Network (WSN) is a new opportunity to conduct a real-time and low-cost monitoring system for volcanic activity. However, the placement of independent WSN sensors in locations that are difficult to access creates new reliability and energy consumption problems. Therefore, we need a reliable communication line design for data transmission and path determination that does not drain sensor energy. This study specifically evaluates the performance of several routing protocols on WSN (proactive, reactive, and hybrid) to provide recommendations for the best routing design for volcanic activity monitoring needs. The simulation results of 6 WSN routing protocols using the NS-2 simulator show that the proactive protocol provides the smallest delay value, and the reactive protocol shows the highest data transmission success ratio but with the best residual energy. In contrast, the hybrid protocol could maintain a stable throughput value during data transmission

Efficient Information Access in Data-Intensive Sensor Networks

Recent advances in wireless communications and microelectronics have enabled wide deployment of smart sensor networks. Such networks naturally apply to a broad range of applications that involve system monitoring and information tracking (e.g., fine-grained weather/environmental monitoring, structural health monitoring, urban-scale traffic or parking monitoring, gunshot detection, monitoring volcanic eruptions, measuring rate of melting glaciers, forest fire detection, emergency medical care, disaster response, airport security infrastructure, monitoring of children in metropolitan areas, product transition in warehouse networks etc.).Meanwhile, existing wireless sensor networks (WSNs) perform poorly when the applications have high bandwidth needs for data transmission and stringent delay constraints against the network communication. Such requirements are common for Data Intensive Sensor Networks (DISNs) implementing Mission-Critical Monitoring applications (MCM applications).We propose to enhance existing wireless network standards with flexible query optimization strategies that take into account network constraints and application-specific data delivery patterns in order to meet high performance requirements of MCM applications.In this respect, this dissertation has two major contributions: First, we have developed an algebraic framework called Data Transmission Algebra (DTA) for collision-aware concurrent data transmissions. Here, we have merged the serialization concept from the databases with the knowledge of wireless network characteristics. We have developed an optimizer that uses the DTA framework, and generates an optimal data transmission schedule with respect to latency, throughput, and energy usage. We have extended the DTA framework to handle location-based trust and sensor mobility. We improved DTA scalability with Whirlpool data delivery mechanism, which takes advantage of partitioning of the network. Second, we propose relaxed optimization strategy and develop an adaptive approach to deliver data in data-intensive wireless sensor networks. In particular, we have shown that local actions at nodes help network to adapt in worse network conditions and perform better. We show that local decisions at the nodes can converge towards desirable global network properties e.g.,high packet success ratio for the network. We have also developed a network monitoring tool to assess the state and dynamic convergence of the WSN, and force it towards better performance

WSN infrastructure for green campus development

A system providing accurate environmental data for campus stakeholders to formulate and evaluate policies of the sustainable campus development is needed. This paper presents the design of WSN infrastructure capable of providing accurate, real-time and reliable environment data, namely PM2.5, SO2, CO, O3, NO2, temperature, humidity, soil moisture and light intensity to be analyzed and presented by servers. This infrastructure is composed of fixed sensor nodes, mobile sensor nodes, display nodes and server nodes. The sensor node provides environment raw data to the server using an RF transceiver. The server processes, stores and presents environment information to public users through Internet and mobile network. This infrastructure can be used as a platform to provide environmental data to decision support system for campus stakeholders, so that a recommendation can be made

Redesigning hazard communication through technology: collaboration, co-production and coherence

Digital and virtual communication impacts increasingly upon the management of natural hazards in an uncertain world, challenging the boundaries between science and society. This study uses sociological theory to explore how technology reduces the mitigation failures and conflicts that scholars often disproportionately prioritise; it also evaluates the evolution of nodal points between communicating stakeholders in a complex hazard management network. Technical innovation has reshaped Iceland’s approach to mitigating risks associated with volcanic events; interconnections between stakeholders within the network evolve through technical innovation and the forming of collaborative engagements that renegotiate the roles and responsibilities of monitoring and response agencies. Interviews and participant observations, with agencies including the Icelandic Meteorological Office, evidence the impact of network evolution upon social media use, inter-agency trust, the expansion of crowdsourcing, and increasingly distributed decision-making frameworks.La communication numérique et virtuelle impacte de plus en plus la gestion des risques naturels dans un monde instable, défiant les frontières entre science et société. Notre étude étudie, sous l'angle de la sociologie, comment la technologie contribue à réduire les défaillances et les divergences en la matière, auxquels se réfèrent trop souvent les scientifiques. Nous analysons également l'évolution des points nodaux entre les acteurs de la communication à l'intérieur d'un réseau complexe de gestion des risques. En Islande les progrès technologiques ont remodelé l'approche de l'atténuation des risques associés aux événements volcaniques. Les interconnexions entre acteurs du réseau évoluent en fonction des innovations techniques et du développement d'engagements de collaboration qui renégocient les rôles et les responsabilités des organismes de contrôle et d'intervention. Les interviews et les observations des différents organismes, y compris l'Office météorologique d'Islande, démontrent l'impact de l'évolution du réseau sur l'utilisation des médias sociaux, la collaboration entre organismes, l'extension du "crowdsourcing", et la répartition croissante des cadres décisionnels

Implementation of Wireless Sensor Network (WSN) for Earthquake Detection

The current earthquake monitoring system uses a seismometer that can capture seismic vibrations very well but is expensive, heavy, and difficult to launch. Therefore, earthquake monitoring stations can only be launched in a few places in small numbers. This study aims to implement a Wireless Sensor Network (WSN) system for earthquake monitoring. The WSN system has advantages in cost, size, and ease of launch, so it is very appropriate to be used for this purpose. An earthquake detection sensor system has been designed in this study using a vibration sensor and a piezoelectric sensor. When an earthquake occurs, the resulting shock will trigger the vibration sensor and activate the sensor node. The shock data is then captured by the piezo sensor and processed by the microcontroller using Fast Fourier Transform (FFT) to determine the frequency value of the shock. The data is then sent to a gateway via a sensor network and uploaded to the Cayenne monitoring website. Operators can then view the data on the website. Three sensor nodes are implemented in this study. The test is done by placing those sensor nodes together in random positions. A shock is then given to the three sensor nodes, and the resulting data is then observed. The results show that the three sensors can detect, retrieve, process, and send shock data to the Cayenne monitoring website

Preface: Approaches and methods to improve risk management in volcanic areas

Active volcanoes can generate multiple types of geological hazards. Besides syneruptive threats (e.g., lava, pyroclastic flows or ash fall), other adverse events such as landslides or lahars can occur at any time. To manage these threats efficiently, three key objectives must be jointly addressed: (1) improving prevention tools, through the collection and acquisition of data on hazards and risks, and its dissemination as maps and scenarios; (2) improving crisis management capabilities, based on monitoring and early warning systems, but also reliable communications systems; and (3) reducing people’s vulnerability and developing recovery and resilience capabilities after an event has occurred. The special issue “Approaches and methods to improve risk management in volcanic areas” presents research results focusing on these three objectives. It demonstrates the utility of addressing them jointly, and particularly examines the case of volcanoes where little knowledge is available. These results were presented at the conference Integrated Approaches for Volcanic Risk Management (Hohenheim University, Stuttgart, 11/12 September 2012) of the European MIAVITA (MItigate and Assess risk from Volcanic Impact on Terrain and human Activities) project

Advances in seismic monitoring at Deception Island volcano (Antarctica) since the International Polar Year

Deception Island is an active volcano located in the south Shetland Islands, Antarctica. It constitutes a natural laboratory to test geophysical instruments in extreme conditions, since they have to endure not only the Antarctic climate but also the volcanic environment. Deception is one of the most visited places in Antarctica, both by scientists and tourists, which emphasize the importance of volcano monitoring. Seismic monitoring has been going on since 1986 during austral summer surveys. The recorded data include volcano-tectonic earthquakes, long-period events and volcanic tremor, among others. The level of seismicity ranges from quiet periods to seismic crises (e.g. 1992-1993, 1999). Our group has been involved in volcano monitoring at Deception Island since 1994. Based on this experience, in recent years we have made the most of the opportunities of the International Polar Year 2007-2008 to introduce advances in seismic monitoring along four lines: (1) the improvement of the seismic network installed for seismic monitoring during the summer surveys; (2) the development and improvement of seismic arrays for the detection and characterization of seismo-volcanic signals; (3) the design of automated event recognition tools, to simplify the process of data interpretation; and (4) the deployment of permanent seismic stations. These advances help us to obtain more data of better quality, and therefore to improve our interpretation of the seismo-volcanic activity at Deception Island, which is a crucial step in terms of hazards assessment.This work has been partially supported by the projects POL2006-08663, CGL2007-28855, CTM2008-03062, CTM2009-07705, CTM2009-08085 and CTM2010-11740 of the Spanish Ministry of Science and Innovation