This paper introduces a peer-to-peer based network for spam filtering.In this network, CopyRank values of emails are stored and used to determine whether a new email is a spam or not Multi-fingerprints method is proposed and employed to deal with spammer's tricks of slightly changing the content of each copy of a spam.

We discuss the projection temporal logic (PTL), based on a primitive projection operator, prj. A framing technique in also presented, usinig which a synchronization operator, await, is defined withim the underlying logic. A framed temporal logic programming language (FTLL) is presented. To illustrate how to use both the language and framing technique, some examples are given.

We define a projection operator in the framework of the temporal logic programming. Its syntax and semantics are presented and illustrated with examples. We also discuss the implementation details of the projection construct.

We generalize Interval Temporal Logic to include absolute time and are motivated to model Hybrid systems consisting of discrete, continuous, and heuristic components. The syntax and semantics of Timed Interval Temporal Logic (TITL) are presented, a visual notation, the extended Statecharts with combine TITL, guarded language, and time constraints in a unified manner, is introduced, and an example for the modelling of soaking pits in a steelworks is employed to illustrate how the formalism operates.

A computational model for hybrid systems consisting of a non-trivial mixture of discreta cvents and continuous activities is presented. Based on this model, a spedcification language, Parallel Hybrid Machine (PHM), which allous us to specify a complex hybrid system in a paralled wag with a graphic representation, is formalized. As a case study, a graphic representation, is modeled by PHMs. Moreover,the PHMs and Hybrid Projection Temporal Logic (HPTL) share a common computational model. Thes enables us to model, analyze and verify a hybrid system in a uniform manner.