Argument Systems provide a rich abstraction within which divers concepts of reasoning, acceptability and defeasibility of arguments, etc., may be studied using a unified framework. Much work has focused on the so-called preferred extensions of such systems, which define the maximal (with respect to ⊆) collectively defensible subsets of arguments within a given system of arguments and attack rel...

In this work we introduce the class of graphs with bounded induced distance of order k, (BID(k) for short). A graph G belongs to BID(k) if the distance between any two nodes in every connected induced subgraph of G is at most k times their distance in G. These graphs can model communication networks in which node failures may occur: at a given time, if sender and receiver are still connected, a...

We study the difference between the standard seeded model of tile self-assembly, and the “seedless” two-handed model of tile self-assembly. Most of our results suggest that the two-handed model is more powerful. In particular, we show how to simulate any seeded system with a two-handed system that is essentially just a constant factor larger. We exhibit finite shapes with a busy-beaver separati...

To investigate secular changes in CO and CH4, we examined monthly means of tropospheric measurements made from samples collected at 19 ®xed sites in the National Oceanic and Atmospheric Administration (NOAA) Climate Monitoring and Diagnostics Laboratory (CMDL) global cooperative ̄ask sampling network. The CH4 data are available for the period 1984±1995. A somewhat shorter time series is availab...

Qualitative coalitional games (QCGs) are a variation of conventional coalitional games in which each coalition may choose to cooperate in a number of different ways, with different choices resulting in potentially different sets of goals being achieved; each agent is associated with a set of goals, the intuition being that an agent is “satisfied” if any of its goals are achieved, but is indiffe...

Introduction Recommender systems in search systems are an established way of pointing the user to related content. Commercial companies like Amazon have been using recommendations for a while by showing the user products related to their current search context or usage behaviour. In digital libraries recommendations can be valuable for researchers, e.g. recommending related literature to a give...