Myounggyu Won

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Situational awareness in a disaster is critical to effective response. Disaster responders require timely delivery of high volumes of accurate data to make correct decisions. To meet these needs, we present DistressNet, an ad hoc wireless architecture that supports disaster response with distributed collaborative sensing, topology-aware routing using a(More)
Duty-cycling is a primary technique significantly improving the energy efficiency of Wireless Sensor Networks (WSNs). Thus, a large number of MAC protocols have been developed for duty-cycled WSNs. Especially, recently proposed receiver-initiated MAC protocols are well suited for extremely low duty-cycled WSNs. However, as it is shown in this paper, they(More)
Geographic routing is well suited for large scale sensor networks deployments, because the per node state it maintains is independent of the network size. However, due to the &#x201C;local minimum&#x201D; caused by holes/obstacles, the path stretch of geographic routing can grow as O(c<sup>2</sup>), where c is the length of the optimal path. Recently,(More)
Resource Allocation has been widely used for improving various performance metrics in wireless networks. Applying resource allocation to a Mobile Ad Hoc Network (MANET), however, is a challenging problem because of dynamic network topology. In this paper, we develop a novel resource allocation scheme designed for MANETs that minimizes the communication cost(More)
Geographic routing is well suited for large scale sensor networks, because its per node state is independent of the network size. However, due to the local minimum caused by holes/obstacles, the path stretch of geographic routing may degrade up to O(c2), where c is the path length of the optimal route. Recently, a geographic routing protocol based on the(More)
Geographic routing is well suited for large-scale wireless sensor networks (WSNs) because it is nearly stateless. One important challenge is that network holes may arbitrarily increase the routing path length. Fortunately, recent studies have shown that constant path stretch is achievable using nonlocal information. The constant stretch, however, is(More)
Reliable network connectivity in wireless sensor networks (WSN) is difficult to achieve. Harsh, unattended, low-security environments and resource-constrained nodes exacerbate the problem. An ability to detect connectivity disruptions, due to either security or environmental problems, allows WSN to conserve power and memory while reducing network(More)
With the advance of mobile devices, cloud computing has enabled people to access data and computing resources without spatiotemporal constraints. A common assumption is that mobile devices are well connected to remote data centers and the data centers securely store and process data. However, for systems like mobile cloud deployed in infrastructureless(More)
Despite the advances in hardware for hand-held mobile devices, resource-intensive applications (e.g., video and image storage and processing or map-reduce type) still remain off bounds since they require large computation and storage capabilities. Recent research has attempted to address these issues by employing remote servers, such as clouds and peer(More)
Time is a critical factor in the Urban Search &amp; Rescue operations immediately following natural and man-made disasters. Building on our collaboration with first responders we identify a set of areas for improving response times: victim detection in collapsed buildings, information storage and collection about buildings (collapsed or not), detection of(More)