Pervasive computing puts forward a number of challenges on reasoning engine

such as: to be context-driven

to deal with frequently change of contexts

and to work in a real-time manner.Traditional reasoning engines can hardly meet these new requirements.In this paper

we present a context-driven reasoning engine ScudCORE (Scud COntext-driven Reasoning Engine)

which takes the first order predicate logic as basis.When contexts vary frequently

ScudCORE reduces the reasoning problems of excessive frequency and inefficiency by the context filtering mechanism.We employ ontology to make the reasoning engine convenient to share

reuse and understand context information both inside and outside it.Also we increase its flexibility with a dynamic rule management module.