We adapt in this paper an analysis-revision cycle to the SCTL-MUS methodology which we will use to support the modification and evolution of requirements specifications in a multi-perspective environment. We take advantage of using our approach in the analysis and revision phases, being able to translate the diagnostic information into system requirements refinements close to the system domain ...

We study how standard auction objectives in sponsored search markets change with refinements in the prediction of the relevance (click-through rates) of ads. We study mechanisms that optimize for a convex combination of efficiency and revenue. We show that the objective function of such a mechanism can only improve with refined (improved) relevance predictions, i.e., the search engine has no di...

Self-stabilizing system is a concept of fault-tolerance in distributed computing. A distributed algorithm is self-stabilizing if, starting from an arbitrary state, it is guaranteed to converge to a legal state in a finite number of states and remains in a legal set of states thereafter. The property of self-stabilization enables a distributed algorithm to recover from a transient fault regardle...

Some of the problems of using refinement alone in the construction of specifications from simple abstract models is used as the spur for the introduction of retrenchment, a method based on the main ideas of refinement, but one which is more liberal in character. The basics of the retrenchment mechanism are presented. The paper then examines one particular way in which a retrenchment and a refin...

Recently, many applications such as scientific databases and decision supporting systems that require comprehensive analysis of a very large amount of data, have been evolved. Summary discovery techniques, which extract compact representations grasping the meanings of large databases, can play a major role in those applications. In this paper, we present an e8ective and robust method to discove...