In a data-driven machine translation system, the lexicon is a core component. Sometimes it is used directly in translation, and sometimes in building other resources, such as a phrase table. But up to now little attention has been paid to how the information contained in these resources can also used backwards to help build or improve the lexicon. The system we propose here alternates lexicon b...

Artificial Intelligence search algorithms search discrete systems. To apply such algorithms to continuous systems, such systems must first be discretized, i.e. approximated as discrete systems. Action-based discretization requires that both action parameters and action timing be discretized. We focus on the problem of action timing discretization. After describing an -admissible variant of Korf...

This paper proposes an image interpolation algorithm exploiting sparse representation for natural images. It involves three main steps: (a) obtaining an initial estimate of the high resolution image using linear methods like FIR filtering, (b) promoting sparsity in a selected dictionary through iterative thresholding, and (c) extracting high frequency information from the approximation to refin...

We propose a new gradient-based method for the extraction of the orientation field associated to a fingerprint, and a regularisation procedure to improve the orientation field computed from noisy fingerprint images. The regularisation algorithm is based on three new integral operators, introduced and discussed in this paper. A pre-processing technique is also proposed to achieve better performa...

Methods for the polynomial eigenvalue problem sometimes need to be followed by an iterative refinement process to improve the accuracy of the computed solutions. This can be accomplished by means of a Newton iteration tailored to matrix polynomials. The computational cost of this step is usually higher than the cost of computing the initial approximations, due to the need of solving multiple li...

In this paper, we present a new method for supporting abstraction refinement in path-sensitive dataflow analysis. We show how an adjustable merge criterion can be used as an interface to control the degree of abstraction. In particular, we partition the merge criterion with two sets of predicates — one related to the dataflow facts being propagated and the other related to path feasibility. The...

Many exponentially-hard problems can be solved by searching through a space of states to determine a sequence of steps constituting a solution. Algorithms that produce optimal solutions (e.g., shortest path) generally require greater computational resources (e.g., time) than their sub-optimal counterparts. Consequently, many optimal algorithms cannot produce any usable solution when the amount ...