Logic-based Perspectives on Query Reformulationover Restricted Interfaces

Efficient Acquisition of Web Data through Restricted Query Interfaces

A wealth of information is available on the Web. But often, such data are hidden behind form interfaces which allow only a restrictive set of queries over the underlying databases, greatly hindering data exploration. The ability to materialize these databases has endless applications, from allowing the data to be effectively mined to providing better response times in Web information integratio...

Query Restricted Bottom - up Eval - uation of Normal Logic

Several program transformations|magic sets, envelopes, NRSU transformations and context transformations, among others|have been proposed for eeciently computing the answers to a query while taking advantage of the query constants. These transformations use sideways information passing strategies (sips) to restrict bottom-up evaluation to facts potentially relevant to the query. It is of interes...

User Perspectives on Query

The di culty of a user query can a↵ect the performance of Information Retrieval (IR) systems. What makes a query di cult and how one may predict this is an active research area, focusing mainly on factors relating to the retrieval algorithm, to the properties of the retrieval data, or to statistical and linguistic features of the queries that may render them di cult. This work addresses query d...

Private Key based query on encrypted data

Nowadays, users of information systems have inclination to use a central server to decrease data transferring and maintenance costs. Since such a system is not so trustworthy, users' data usually upkeeps encrypted. However, encryption is not a nostrum for security problems and cannot guarantee the data security. In other words, there are some techniques that can endanger security of encrypted d...

Using a Description Logic to Drive Query Interfaces