Supplementing an AD-HOC Wireless Network Routing Protocol with Radio Frequency Identification (RFID) Tags

Wireless sensor networks (WSNs) have a broad and varied range of applications, yet all of these are limited by the resources available to the sensor nodes that make up the WSN. The most significant resource is energy. A WSN may be deployed to an inhospitable or unreachable area, leaving it with a non-replenishable power source. This research examines a way of reducing energy consumption by augmenting the nodes with radio frequency identification (RFID) tags that contain routing information. It was expected that RFID tags would reduce the network throughput, the ad hoc on-demand distance vector (AODV) routing traffic sent, and the amount of energy consumed. However, the results show that RFID tags have little effect on the network throughput or the AODV routing traffic sent. They also increase ETE delays in sparse networks as well as the amount of energy consumed in both sparse and dense networks. Furthermore, there was no statistical difference in the amount of user data throughput received. The density of the network is shown to have an effect on the variation of the data but the trends are the same for both sparse and dense networks. This counter-intuitive result is explained, and conditions for such a scheme to be effective are discussed

Nocturnal apnea in Chiari type I malformation

Contains fulltext : 98153.pdf (publisher's version ) (Closed access)A 4-year-old girl presented with sleep-disordered breathing. Her parents described breathing pauses of up to 20 s and progressive tiredness during the day. Obstructive apneas from an enlarged adenoid were thought to be the most probable cause. However, an adenotomy did not resolve the problem. Polysomnography demonstrated central apneas, and cerebral magnetic resonance imaging revealed a Chiari type I malformation. We describe the differential diagnosis of apnea in children and the role of polysomnography in the distinction between obstructive and central apneas. Conclusion: This case illustrates that, in children with apnea, it is important to consider central causes as well as the more common obstructive causes, even in the absence of additional neurological signs or symptoms