Nodal congestion in ABR traac control design is often detected by comparison of present queue size with a pre-assigned queue-threshold. Such queue-threshold detection has the disadvantage of delayed congestion detection and undesired extension of congestion periods. In consequence, the oscillation of ABR traac in each control feedback loop is unnecessarily extended and magniied, causing a large...

This paper reports the characteristics of and mutual relationships between various combinatorial structures that give rise to certain imprimitive nonsymmetric three-class association schemes. Nontrivial relation graphs of an imprimitive symmetric 2-class association scheme are m ◦ Kr, (the union of m copies of the complete graph on r vertices) and its complement m ◦Kr, (the complete m-partite s...

The Stinson-Wei traceability scheme (known as traceability scheme) was proposed for broadcast encryption as a generalization of the Chor-Fiat-Naor traceability scheme (known as traceability code). Cover-free family was introduced by Kautz and Singleton in the context of binary superimposed code. In this paper, we find a new relationship between a traceability scheme and a cover-free family, whi...

Fluorescent building blocks: Tetracarboxyamides with a central fluorescent diaminoterephthalate unit were prepared from succinyl succinates following a combinatorial-like strategy. The 2,5-diaminoterephthalates (see scheme; PG=protecting group) possess four points of diversification and are introduced as new scaffolds for combinatorial chemistry.2,5-Diaminoterephthalates that possess four point...

Many tasks in probabilistic reasoning can be cast as max-sum-product problems, a hard class of combinatorial problems. We describe our results in obtaining a new approximation scheme for the problem, that can be turned into an anytime procedure. For many tasks, this scheme can be shown to be asymptotically the best possible heuristic.

Abstract We introduce a conjecture on Virasoro constraints for the moduli space of stable sheaves smooth projective surface. These generalise Hilbert scheme surface found by Moreira and Moreira, Oblomkov, Okounkov Pandharipande. verify in many nontrivial cases using combinatorial description equivariant Klyachko.

The term combinatorial Gray code was introduced in 1980 to refer to any method for generating combinatorial objects so that successive objects differ in some pre-specified, small way. This notion generalizes the classical binary reflected Gray code scheme for listing n-bit binary numbers so that successive numbers differ in exactly one bit position, as well as work in the 1960’s and 70’s on min...

This paper introduces the Stellar Simplification scheme, a fast implementation of the Four–Face Cluster algorithm. In this scheme, a probabilistic optimization heuristic substitutes the priority queue of the original algorithm, which results in a 40% faster algorithm with the same order of distortion. This implementation uses a very concise data structure which consists only of two arrays of in...

A combinatorial random variable is a discrete random variable defined over a combinatorial set (e.g., a power set of a given set). In this paper we introduce combinatorial Markov random fields (Comrafs), which are Markov random fields where some of the nodes are combinatorial random variables. We argue that Comrafs are powerful models for unsupervised and semi-supervised learning. We put Comraf...