Helly’s theorem is one of the fundamental results in discrete geometry [9]. It states that if every 6 d+1 sets in a set system S of convex sets in R have non-empty intersection then all of the sets in S have non-empty intersection. Equivalently, if the entire family S has empty intersection, then there is a subset S ′ ⊂ S (a witness) of size 6 d+1 which also has empty intersection. Over the yea...

Mobile agents are computer programs that act autonomously on behalf of a user or its owner and travel through a network of heterogeneous machines. Fault tolerance is important in their itinerary. In this paper, existent methods of fault tolerance in mobile agents are described which they are considered in linear network topology. In the methods three agents are used to fault tolerance by cooper...

Inaccuracies in eyewitness accounts can occur when witnesses are exposed to post-event misinformation via discussion with a co-witness. The current study examined the role of co-witness relationship by comparing the memory performance of pairs of romantic couples, friends and previously unacquainted strangers with that of individuals. Ninety-six participants viewed an event and then discussed t...

We show that the default-all propagation scheme for database annotations is dangerous. Dangerous here means that it can propagate annotations to the query output which are semantically irrelevant to the query the user asked. This is the result of considering all relationally equivalent queries and returning the union of their where-provenance in an attempt to define a propagation scheme that is...

We propose an efficient blind certification protocol with interesting properties. It falls in the Groth-Sahai framework for witness-indistinguishable proofs, thus extended to a certified signature it immediately yields non-frameable group signatures. We use blind certification to build an efficient (offline) e-cash system that guarantees user anonymity and transferability of coins without incre...

The record stored in the brains of the witness and perpetrator is often a much more comprehensive account of the crime than what can be pieced together from connecting a few specific features of the crime scene with a few specific features of the perpetrator. This record has not been accessible to scrutiny. The stored record has the advantage of often providing by far the most comprehensive acc...

Epistemic Indefinites (henceforth EIs) are indefinites in which this ignorance inference is conventionalized (Jayez and Tovena, 2006; Alonso-Ovalle and MenéndezBenito, 2010). Examples of epistemic indefinite determiners are German irgendein (Haspelmath, 1997; Kratzer and Shimoyama, 2002) and Italian un qualche (Zamparelli, 2007). Sentences (2) and (3) make an existential claim, and additionally...

We construct a new class of positive indecomposable maps in the algebra of d × d complex matrices. Each map is uniquely characterized by a cyclic bistochastic matrix. This class generalizes a Choi map for d = 3. It provides a new reach family of indecomposable entanglement witnesses which define important tool for investigating quantum entanglement.