— In location-based, mobile continual query (CQ) systems, two key measures of quality of service (QoS) are: freshness and accuracy. To achieve freshness, the CQ server must perfo...
Database query languages can be intimidating to the nonexpert, leading to the immense recent popularity for keyword based search in spite of its significant limitations. The holy ...
Nearest-neighbor queries are an important query type for commonly used feature databases. In many different application areas, e.g. sensor databases, location based services or fac...
Multidimensional aggregation queries constitute the single most important class of queries for data warehousing applications and decision support systems. The bottleneck in the ev...
Much attention has been paid to the relative effectiveness of interactive query expansion versus automatic query expansion. Although interactive query expansion has the potential ...