It is well known that some XML elements correspond to objects (in the sense of object-orientation) and others do not. The question we consider in this paper is what benefits we can derive from paying attention to such object semantics, particularly for the problem of keyword queries. Keyword queries against XML data have been studied extensively in recent years, with several lowest-common-ances...

We derive a new generalization of lowest common ancestors (LCAs) in dags, called the lowest single common ancestor (LSCA). We show how to preprocess a static dag in linear time such that subsequent LSCA-queries can be answered in constant time. The size is linear in the number of nodes. We also consider a “fuzzy” variant of LSCA that allows to compute a node that is only an LSCA of a given perc...

A k-repeat is a stringwk=u∗ kv that matches more than one substring of x, where ∗ is the don’t care letter and k > 0.We propose an O(n log n)-time algorithm for computing all longest k-repeats in a given string x = x[1..n]. The proposed algorithm uses suffix trees to fulfill this task and relies on the ability to answer lowest common ancestor queries in constant time. © 2006 Elsevier B.V. All r...

We present in this paper novel techniques that determine the semantic relationships among genes and gene products. We implemented these techniques in a middleware system called GOtoGene, which resides between user application and Gene Ontology database. Given a set S of genes, GOtoGene would return another set S  of genes, where each gene in S  is semantically related to each gene in S . The ...

The least common subsumer (lcs) w.r.t general EL-TBoxes does not need to exists in general due to cyclic axioms. In this paper we present an algorithm for computing role-depth bounded EL-lcs based on the completion algorithm for EL. We extend this computation algorithm to a recently introduced probabilistic variant of EL: Prob-EL.