We present a logic for analyzing cryptographic protocols. This logic encompasses a uni cation of four of its predecessors in the BAN family of logics, namely those given in [GNY90], [AT91], [vO93], and BAN itself [BAN89]. We also present a model-theoretic semantics with respect to which the logic is sound. The logic herein captures all of the desirable features of its predecessors and more; non...

OBJECTIVES This article examines changes in the health status of Canadian adults between 1978/79 and 1996/97. DATA SOURCES Data are from the the Canadian Vital Statistics Data Base, the 1991 General Social Survey, the 1978/79 Canada Health Survey (CHS), and the 1996/97 National Population Health Survey (NPHS). ANALYTICAL TECHNIQUES Age-specific mortality rates are presented for 1978 and 199...

subtle superiority complex in modern man when he considers himself in relation to his predecessors. After all, modern man has computers, DVDs, hi-tech automobiles, jet aircraft and the achievement of putting men on the moon, among other things. There is a certain smugness in the average modern man who thinks to himself how much better he is than those earlier in history who knew nothing of digi...

Let d be a Turing degree containing differences of recursively enumerable sets (d.r.e.sets ) and R[d] be the class of less than d r.e.degrees in which d is relatively enumerable (r.e.). A.H.Lachlan proved that for any non-recursive d.r.e. d R[d] is not empty. We show that the r.e.degree defined by Lachlan for a d.r.e.set D ∈d is just the minimum degree in which D is r.e. Then we study for a giv...

In the presence of high uncertainty and limited experience, can observing the actions of other acquiring predecessors help firms make better acquisition decisions? Using a sample of crossborder M&As conducted by US acquirers in developing countries, we document a positive and significant relationship between an acquirer’s performance and its predecessors’ acquisition activity. This relationship...

In traditional precedence-constrained scheduling a task is ready to execute when all its predecessors are complete. We call such a task an AND task. In this paper we allow certain tasks to be ready when just one of their predecessors is complete. These tasks are known as OR tasks. We analyze the complexity of two types of real-time AND/OR task scheduling problems. In the rst type of problem, al...