We study the problem of distributing a file initially located at a server among a set of peers. Peers who downloaded the file can upload it to other peers. The server and the peers are connected to each other via a core network. The upload and download rates to and from the core are constrained by user and server specific upload and download capacities. Our objective is to minimize the makespan...

Peer-to-peer networks offer attractive features such as decentralized computing, fault tolerance, sharing and aggregating of resources (e.g., SETI@home). A common (and limiting) assumption on peer-to-peer network is that, in order to achieve fair sharing and fault tolerance, all computers in the network should be considered equal and there should be no server nor explicit structuring in the net...

Using a qualitative monozygotic (MZ) twin differences design we explored whether adolescent MZ twins report discordant peer relationships and, if so, whether they perceive them as causes, consequences or correlates of discordant behaviour. We gathered free-response questionnaire data from 497 families and conducted in-depth telephone interviews with 97 of them. Within this dataset n = 112 famil...

Even though collaboration in peer learning has been shown to have a positive impact for students, there has been little research into collaborative peer learning dialogues. We analyze such dialogues in order to derive a model of knowledge co-construction that incorporates initiative and the balance of initiative. This model will be embedded in an artificial agent that will collaborate with stud...

background: the purpose of this study was to evaluate the effectiveness of peer education among university students for reproductive health promotion based on researchers' experiences. methods: this interventional study was conducted in qazvin university of medical science during 2002 to 2004 through stakeholders' partnership and selection of 24 volunteer students according to their knowledge, ...