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A volcano monitoring system plays a key role for launching emergency early warning, and the use of alternative technologies have proven their effectiveness in this setting, which is the case of wireless sensor networks. For surveillance systems, the real-time requirement is mandatory due to the need for immediate access to the signals derived from a natural disaster where the goal is safeguarding...
Wireless Sensor Network (WSN) is a large network of sensor nodes, which operates in low power and capable of transmitting to a shorter distance with low bandwidth. It comprises of sensing unit, processing unit, memory unit, power supply and transceiver. As these sensor nodes are battery operated, the lifetime of the sensor node depends on the life of the battery. The sensor nodes in the network communicate...
There has been much interest recently in improving power saving and cost efficiency by monitoring the operation status of various facilities over networks. Wireless networks, especially cellular networks, are advantageous in terms of their mobility, coverage, and scalability. However, a weak point is their low reliability due to rapid changes in available bandwidth. We fabricated a prototype of a...
The recent emergence of the sensor networks technology is significantly impacting the capabilities for automated distributed monitoring of environments. The low manufacturing cost of sensors, increased coverage and accuracy in distributed sensing due to their large deployments and their ability to operate in inhospitable terrains has made them an amenable technology for various surveillance and monitoring...
Most researchers encountered the following two problems when working with real Wireless Sensor Networks (WSNs): (1) Sensor nodes cannot satisfy application requirements even though the nominal sensing/transmission rates of these nodes are much higher than required. (2) In a WSN deployed in a large area, it is difficult or infeasible to get runtime performance evaluation of sensor nodes. We found out...
This paper proposes an adaptive 2-level active period control method with adaptive backoff window based on traffic load in each cluster for cluster-based wireless sensor networks (WSNs) employing IEEE 802.15.4 medium access control (MAC) protocol under temporal and geographical non-uniform traffic distribution. The proposed method consists of three elements: cluster level active period control, network...
Low power consumption and small footprint make 802.15.4/ZigBee based devices well suited for personal healthcare applications, representing a promising alternative to patient monitoring under important scenarios such as emergency, postop, continuous care, and chronic diseases. However, their use in a healthcare facility to monitor several mobile patients poses several difficulties, mainly because...
Low power consumption and small footprint make 802.15.4/ZigBee based devices well suited for personal healthcare applications, representing a promising alternative to patient monitoring under important scenarios such as emergency, post-op, continuous care, and chronic diseases. However, their use in a healthcare facility to monitor several mobile patients poses several difficulties, mainly because...
Distributed wireless sensor networks (WSNs) promise to change the way industrial systems and structures are monitored and controlled. This paper presents a WSN simulation model for a partial discharge (PD) WSN monitoring system for HV systems. A simulation model of a ZigBee sensor network has been simulated to be positioned at 6 locations of an HV transformer to record the PD readings and associated...
This paper proposes an adaptive 2 level active period length control method based on traffic load in each cluster for cluster-based wireless sensor networks (WSNs) employing IEEE 802.15.4 medium access control (MAC) protocol. The proposed method consists of two active period length controls: cluster level control and network level control. In the cluster level control, cluster heads autonomously control...
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