During the last decade, the advance of Internet has enabled the emergence of previously nonexistent type of human social structures virtual 'online' communities. As compared to the traditional communities, online communities are distinguished by the drastic reduction of the requirement for the physical proximity and geographical clustering of their members. The primary cause of this shift away ...

We consider qualitative and quantitative model-checking problems for probabilistic pushdown automata (pPDA) and various temporal logics. We prove that the qualitative and quantitative model-checking problem for ω-regular properties and pPDA is in 2-EXPSPACE and 3-EXPTIME, respectively. We also prove that model-checking the qualitative fragment of the logic PECTL∗ for pPDA is in 2-EXPSPACE, and ...

Dealing with service composition is an important and challenging issue of distributed systems. Existing works investigate mechanisms for analyzing and synthesizing a composition based on qualitative properties which characterize operations and/or messages choreography constraints. Apart from these qualitative properties, quantitative properties such as time related features are a crucial settin...

Online social networks are rapidly asserting themselves as popular services on the Web. A central point is to determine whether two distinct users can be considered similar, a crucial concept with interesting consequences on the possibility to accomplish targeted actions like, for example, political and social aggregations or commercial promotions. In this chapter, the authors propose an approa...

The validation of alternative microbiological testing is an opportunity for a manufacturer to decrease the amount of time required for laboratory results. To properly validate these alternatives, a practitioner must first identify what is being studied. The regulatory effect on established product and process specifications and levels must be completely evaluated, as changing the method of anal...

Caryophyllaceae is the fifth largest Iranian plant family in terms of number of species where most of its species are Irano-Turanian. About 30% of these species are endemic of Iran. There are continuously uncertainties regarding the circumscription of genera, and especially because of new molecular and phylogenetic studies that in many cases do not confirm the traditional generic circumscriptio...