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Wireless sensor networks (WSNs) provide a convenient way to monitor the physical environment. Exploiting the context-aware capability of WSN to achieve energy conservation in intelligent buildings is an attractive direction. We therefore propose an intelligent and personalized energy-conservation system by wireless sensor networks (iPower). This system(More)
— In this paper, a hybrid sensor network consisting of static and mobile sensors is considered, where static sensors are used to detect events, and mobile sensors can move to event locations to conduct more advanced analysis. By exploring the load balance concept, we propose a CentralSD algorithm to efficiently dispatch mobile sensors. Our algorithm is(More)
By introducing the relay capability, the IEEE 802.16j standard is developed to improve the WiMAX performance. Under the transparent mode, existing studies aim at improving network throughput by increasing the transmission rates of <i>mobile stations (MSs)</i>. However, we show that using higher rates will let MSs consume more energy. In the paper, we define(More)
Wireless sensor networks (WSNs) offer a convenient way to monitor physical environments. In the past, WSNs are all considered static to continuously collect information from the environment. Today, by introducing intentional mobility to WSNs, we can further improve the network capability on many aspects, such as automatic node deployment, flexible topology(More)
—We consider a hybrid wireless sensor network with static and mobile nodes. Static sensors monitor the environment and report events occurring in the sensing field. Mobile sensors are then dispatched to visit these event locations to conduct more advanced analysis. A big challenge is how to schedule these mobile sensors' traveling paths in an(More)
Wireless channels are characterized by more serious bursty and location-dependent errors. Many packet scheduling algorithms have been proposed for wireless networks to guarantee fairness and delay bounds. However, most existing schemes do not consider the difference of traffic natures among packet flows. This will cause the delay-weight coupling problem. In(More)
The IEEE 802.16j standard is defined to enhance WiMAX networks with relay capacity. Under the transparent mode, existing studies only target at improving network throughput by increasing the transmission rates of mobile stations (MSs) and maximizing concurrent transmissions. However, using a higher transmission rate or allowing more concurrent transmissions(More)
Constrained by the physical environments, the long-thin topology has recently been promoted for many practical deployments of wireless sensor networks (WSNs). In general, a long-thin topology is composed of a number of long branches of sensor nodes, where along a branch each sensor node has only one potential parent node toward the sink node. Although data(More)
Sensor deployment is a critical issue since it reflects the cost and detection capability of a wireless sensor network. Although lots of work has addressed this issue, most of them assume that the sensing field is an open space and there is a special relationship between the communication range and sensing range of sensors. In this work, we consider the(More)