522 search results - page 77 / 105 » Answering Aggregation Queries in a Secure System Model |
IDEAS
2000
IEEE
14 years 10 hour ago
2000
IEEE
Most operations of the relational algebra or SQL - like projection with duplicate elimination, join, ordering, group by and aggregations - are efficiently processed using a sorted...
WWW
2008
ACM
14 years 8 months ago
2008
ACM
This paper presents PrivacyGrid - a framework for supporting anonymous location-based queries in mobile information delivery systems. The PrivacyGrid framework offers three unique...
CIVR
2007
Springer
14 years 1 months ago
2007
Springer
This paper describes the technical details of SemRetriev, a prototype system for image retrieval which combines the use of an ontology which structures an image repository and of ...
SACMAT
2005
ACM
14 years 1 months ago
2005
ACM
We investigate a generalization of the notion of XML security view introduced by Stoica and Farkas [17] and later refined by Fan et al. [8]. The model consists of access control ...
WWW
2003
ACM
14 years 8 months ago
2003
ACM
This paper focuses on the optimization of the navigation through voluminous subsumption hierarchies of topics employed by Portal Catalogs like Netscape Open Directory (ODP). We ad...