The IEEE 802.15.4 protocol proposes a flexible communication solution for low-rate wireless personal area networks (LR-WPAN) including wireless sensor networks (WSNs). It presents the advantage to fit different requirements of potential applications by adequately setting its parameters. When in beaconenabled mode, the protocol can provide timeliness guarantees by using its Guaranteed Time Slot ...

Intruder detection is an important application in Wireless Sensor Networks (WSNs). Barrier coverage, which requires much fewer sensors than full coverage, is broadly known as an appropriate model of coverage for such an application. However, previous works all focus on providing 1D barrier coverage on a thin belt region based on global network information. In this paper, we introduce the concep...

Sincere thanks to… Professor Char Miller and Professor Bo Cutter for their guidance throughout the thesis process. My family and friends for all the love, cheer, and support. You are my sunshine.

Peter Ashwood-Smith (Nortel Networks Corp.) Internet Draft Ayan Banerjee (Calient Networks) Expiration Date: April 2001 Lou Berger (Movaz Networks) Greg Bernstein (Ciena Corporation) John Drake (Calient Networks) Yanhe Fan (Axiowave Networks) Kireeti Kompella (Juniper Networks, Inc.) Eric Mannie (GTS Network Services) Jonathan P. Lang (Calient Networks) Bala Rajagopalan (Tellium, Inc.) Yakov Re...

The increasing demand for real-time applications has made the Quality of Service (Qos) support for wireless sensor networks (WSN) a fairly new research framework. In this paper, we propose an extended model of the Beacon enabled IEEE 802.15.4 including the Guaranteed Time Slot GTS allocation mechanism in the aim to analyze and evaluate network performances. Series of extensive simulations were ...

Background Unmet health needs of populations around the world are a major contributor to lagging health outcomes globally. Medical professionals have a duty to address the health needs of their communities. In a globalizing world, the needs may seem limitless. Yet, most training involves immersion in one health system and its resources. How do practitioners reconcile this potentially limitless ...

In the current global environmental crisis medical aid and disaster relief is given by the UN and its branches, by governments and by NGOs, who regard it as their duty to address large-scale humanitarian catastrophes. The duty to give medical aid rests on traditional interpretations of health security and on the bioethical imperatives to relieve suffering and to save lives. However, those princ...

We consider the energy efficiency of medium access control (MAC) in low power wireless communication where multiple channels are available and the duty cycle of (send, receive, and idle) channel access is controllable. We show that in this setting maximization of MAC energy efficiency reduces to maximizing the aggregate channel utilization and minimizing the aggregate duty cycle channel access....

In traditional GNSS receiver architectures, the receiver normally acquires the visible satellite signals and keeps tracking them throughout their availability. Although this approach is perfectly viable for reliable and accurate positioning in most applications, tracking all satellites in view throughout the receiver power-on duration results in a significant penalty on power consumption in bat...