The Inequality Necessary Condition Analyzer (INCA) is a finite-state verification tool that has been able to check properties of some very large concurrent systems. INCA checks a property of a concurrent system by generating a system of inequalities that must have integer solutions if the property can be violated. There may, however, be integer solutions to the inequalities that do not correspo...

Two security domains that want to exchange information securely may need to agree on translations of Mandatory Access Control (MAC) labels of their information, if their MAC labels have a different syntax or semantics. It is desirable that these translations do not introduce any confidentiality violations. In this paper we present a property, the Security Level Translation Property (SLTP), whic...

We give a counterexample to a conjecture by Wild about binary matroids. We connect two equivalent lines of research in matroid theory: a simple type of basis-exchange property and restrictions on the cardinalities of intersections of circuits and cocircuits. Finally, we characterize direct sums of series-parallel networks by a simple basis-exchange property. In [9], Wild proposed a characteriza...

By utilizing the state-space representation of Markov-switching vector autoregressive models, we develop impulse response functions with regards to shocks to variables of the system The proposed analysis in related to the concept of generalized impulse responses introduced by Koop, Pesaran and Potter (1996) but characterizes the properties of the model dynamics in a more concise form. In contra...

Online social networks (OSNs) have created new and exciting ways to connect and share information. Perhaps no site has had a more profound effect on information exchange than Twitter.com. In this paper, we study large-scale graph properties and lesser-studied local graph structures of the explicit social network and the implicit retweet network in order to better understand the relationship bet...

We propose a class of protocol transformations, which can be used to (1) develop (families of) security protocols by refinement and (2) abstract existing protocols to increase the efficiency of verification tools. We prove the soundness of these transformations with respect to an expressive security property specification language covering secrecy and authentication properties. Our work clarifi...

This paper presents an analysis of output queued cell switches which are introduced with generic non-uniformly distributed traffic. Random arbitration is employed whereby non-empty queues compete equally for service within each switching interval. In particular, we study the case of two-state Markov-modulated arrivals in which input ports generate bursty streams that are non-uniformly distribut...