Abstract. With recent advances of wireless ad hoc networking, especially opportunistic forwarding and cognitive radio, there is an increasing concern that existing mobility models are insufficient to represent network mobility in real world settings. In this paper, we discuss our proposal for a more realistic mobility model which captures key features of human movements in pervasive markets. Our findings lead to a non-traditional mobility model which can be used to reconstruct the statistical patterns commonly observed in the literature, and facilitate the study of mobile communication and software engineering design problems under the context of pervasive computing for markets. 1

Abstract. This paper studies abstraction and refinement techniques in the setting of multi-valued model checking for the μ-calculus. Two dimensions of abstractions are identified and studied: Abstraction by joining states of the underlying multi-valued Kripke structure as well as abstraction of truth values, for each following both an optimistic and pessimistic account. It is shown that our notion of abstraction is conservative in the following sense: The truth value in a concrete system is “between ” the optimistic and pessimistic assessment. Moreover, model checking of abstracted systems is shown to be again a multi-valued model checking problem, allowing to reuse multi-valued model checking engines. Finally, whenever the optimistic and pessimistic model checking result differ, the cause for such an assessment is identified, allowing the abstraction to be refined to eventually yield a result for which both the optimistic and pessimistic assessment coincide. 1