We say that a collection of finite sets has a common intersection of size t provided that the intersection of each pair of these sets is equal to the intersection of all of them and this intersection has exactly t elements. A family of sets with this property is therefore a strong 0-system [6 ;7]. Denote by f(n ;r,k,t) the smallest integer with the property that if F is any family of subsets ea...

In the given article we generalize a construction presented in [3]. We give a method of constructing a cover-free (s, ℓ)-code. For k > s, our construction yields a (n s) ℓ × n k cover-free (s, ℓ)-code with a constant column weight. Let N , t, s and ℓ be integers, where 1 ≤ s < t and 1 < ℓ < t − s. Let denote the equality by definition, |A| – the size of the set A and [N ] {1, 2,. .. , N } – the...

Recent years have witnessed a steady growth in the availability of wide area multi service networks These support a variety of tra c types including data control messages audio and video Consequently they are often thought of as integrated media carriers For example ISDN is often spoken of as an integrated voice and data network To date however use of these networks has been limited to isolated...

A major problem in our earlier proposal for a C interface was that a part of the interface was not portable between platforms. The libcc interface solves this problem by using a C compiler and its .h-files. The .h-files contain knowledge about the specific platform, and the C compiler automatically inserts the necessary conversions between Forth and C types. In this paper we describe the libcc ...

For a binary code of length v, a v-word w produces by a set of codewords {w, . . . , w} ✓ if for all i = 1, . . . , v, we have wi 2 {w i , . . . , w i }. We call a code r-secure frameproof of size t if | | = t and for any v-word that is produced by two sets C1 and C2 of size at most r, then the intersection of these sets is non-empty. A d-biclique cover of size v of a graph G is a collection of...

Galvin showed that for all fixed δ and sufficiently large n, the n-vertex graph with minimum degree δ that admits the most independent sets is the complete bipartite graph Kδ,n−δ. He conjectured that except perhaps for some small values of t, the same graph yields the maximum count of independent sets of size t for each possible t. Evidence for this conjecture was recently provided by Alexander...

This paper describes how a runtime support library can be used as compiler runtime support in irregular applications. The CHAOS runtime support library carries out optimizations designed to reduce communication costs by performing software caching, communication coalescing and inspector/executor preprocessing. CHAOS also supplies special purpose routines to support speci c types of irregular re...

We have observed three Type 2 radio loud active galactic nuclei using the VLBA at five frequencies between 1.6 GHz and 15 GHz, in a search for the free-free absorption cutoff predicted by some models for optically-obscuring dusty molecular tori. We find no evidence for sharp cutoffs toward low frequencies in any of the sources. However, one source, OW637, has VLBI components which are steeply f...

For a positive integer k, let k + k denote the poset consisting of two disjoint k-element chains, with all points of one chain incomparable with all points of the other. Bosek, Krawczyk and Szczypka showed that for each k ≥ 1, there exists a constant ck so that First Fit will use at most ckw 2 chains in partitioning a poset P of width at most w, provided the poset excludes k+k as a subposet. Th...

We study the problem of finding robust equilibria in multiplayer concurrent games with mean payoff objectives. A (k, t)-robust equilibrium is a strategy profile such that no coalition of size k can improve the payoff of one its member by deviating, and no coalition of size t can decrease the payoff of other players. We are interested in pure equilibria, that is, solutions that can be implemente...