Saliency algorithms in content-based image retrieval are employed to retrieve the most important regions of an image with the idea that these regions hold the essence of representative information. Such regions are then typically analysed and described for future retrieval/classification tasks rather than the entire image itself thus minimising computational resources required. We show that we ...

A Private Information Retrieval (PIR) scheme is a protocol in which a user retrieves a record out of N from a replicated database, while hiding from the database which record has been retrieved, as long as the different replicas do not collude. A specially interesting sub-field of research, called singledatabase PIR, deals with the schemes that allow a user to retrieve privately an element of a...

Private Information Retrieval (PIR), despite being well studied, is computationally costly and arduous to scale. We explore lower-cost relaxations of information-theoretic PIR, based on dummy queries, sparse vectors, and compositions with an anonymity system. We prove the security of each scheme using a flexible differentially private definition for private queries that can capture notions of i...

Private Information Retrieval (PIR), despite being well studied, is computationally costly and arduous to scale. We explore lower-cost relaxations of information-theoretic PIR, based on dummy queries, sparse vectors, and compositions with an anonymity system. We prove the security of each scheme using a flexible differentially private definition for private queries that can capture notions of i...

Private Information Retrieval (PIR) protocols allow a user to retrieve a data item from a database while hiding the identity of the item being retrieved. Specifically, in information-theoretic, -server PIR protocols the database is replicated among servers, and each server learns nothing about the item the user retrieves. The cost of such protocols is measured by the communication complexity of...

The aim of the present study was to investigate whether and by which mechanism; histamine can induce state-dependent retrieval of passive avoidance task. The pre-training or pre-test intracerebroventricular (i.c.v.) injection of histamine (20µg/mouse) impaired retrieval, when it was tested 24 h later. In the animals, which retrieval was impaired due to histamine pre-training administration, pre...

We propose a set of solutions for managing a large scale RDF semantic repository from the perspective of RDF graph model. A native storage instead of relational database is used to hold RDF. Indices supporting regular path expression, full-text retrieval and partial OWL Lite inference are built above the storage model. Semantic ranking for resources are provided as well.

Reformulating the user query is a technique that aims to improve the performance of an Information Retrieval System (IRS) in terms of precision and recall. This paper tries to evaluate the technique of query reformulation guided by an external resource for Arabic texts. To do this, various precision and recall measures were conducted and two corpora with different external resources like Arabic...