We study the fundamental problem of how devices, operating over a wireless medium, can discover potential communication partners. For the devices, the spectrum is divided into m frequency channels. As multiple devices share these channels, they have to cope with collisions while they are trying to find other devices in the system. Moreover, we assume an adversarial jammer to block some of the a...

The chapter examines seamless learning, where the aim is to enable a continuous fl ow of meaning-making despite changes in the physical and social context. One way to achieve this is by inducing a fl ow state such that learners are so engaged in a mobile learning activity that they lose awareness of their surroundings. Mobile educational games may be one way to achieve such fl ow, but this is n...

OBJECTIVES There is preliminary evidence for the efficacy of positive psychology interventions for pain management. The current study examined the effects of an internet-based positive psychology self-help program for patients with chronic musculoskeletal pain and compared it with an internet-based cognitive-behavioral program. MATERIALS AND METHODS A randomized controlled trial was carried o...

A realistic threat model for cryptographic protocols or for languagebased security should include a dynamically growing population of principals (or security levels), some of which may be compromised, that is, come under the control of the adversary. We explore such a threat model within a pi-calculus. A new process construct records the ordering between security levels, including the possibili...

Current differential based wide area protection (WAP) has recently been proposed as a technique to increase the reliability of protection systems. It increases system stability and can prevent large contingencies such as cascading outages and blackouts. This paper describes how power differential protection (PDP) can be used within a WAP and shows that the algorithm operates correctly for a...