Skyline queries have been widely used as a practical tool for multi-criteria decision analysis and for applications involving preference queries. For example, in a typical online retail application, skyline queries can help customers select the most interesting, among a pool of available, products. Recently, reverse skyline queries have been proposed, highlighting the manufacturer’s perspective...

DEFINITION: Given a set of points p1, p2, ......., pn, the skyline query returns a set of points P, called as the skyline points, such that any point pi ∈ P is not dominated by any other point in the dataset. A point p1 dominates another point p2, if p1 is not worse than p2 in all dimensions and p1 is better than p2 in at least one dimension. In other words, a point p1 dominates another point p...

With development of SOA, the complex problem can be solved by combining available individual services and ordering them to best suit user's requirements. Web services composition is widely used in business environment. With the features of inherent autonomy and heterogeneity for component web services, it is difficult to predict the behavior of the overall composite service. Therefore, transact...

Several algorithms for processing reverse skyline queries have been proposed in recent literature. However, these algorithms are based on pre-processing approaches, and hence involve complex procedures and waste storage space due to inefficient use of storage. In addition, they are not robust to frequently changing data as, they have to re-compute and update the pre-computed results. To overcom...

Estimation of demographic history from nucleotide sequences represents an important component of many studies in molecular ecology. For example, knowledge of a population's history can allow us to test hypotheses about the impact of climatic and anthropogenic factors. In the past, demographic analysis was typically limited to relatively simple population models, such as exponential or logistic ...

The skyline of a set of points in the plane is the subset of maximal points, where a point (x, y) is maximal if no other point (x′, y′) satisfies x′ ≥ x and y′ ≥ x. We consider the problem of preprocessing a set P of n points into a space efficient static data structure supporting orthogonal skyline counting queries, i.e. given a query rectangle R to report the size of the skyline of P ∩ R. We ...

Constrained skyline queries retrieve all points that optimize some user’s preferences subject to orthogonal range constraints, but at significant computational cost. This paper is the first to propose caching to improve constrained skyline query response time. Because arbitrary range constraints are unlikely to match a cached query exactly, our proposed method identifies and exploits similar ca...

The database skyline query (or non-domination query) has a spatial form: Given set P with n point sites, and S of m locations interest, site p ∈ is if only for each q ∖ { } , there exists at least one location s that closer to than . We reduce the problem determining points finding sites have non-empty cells in an additively weighted Voronoi diagram under convex distance function. weights said ...

With the adoption of service-oriented manufacturing modes, more and services are released over service platforms. As it is known, problem QoS (Quality Service)-aware composition NP-hard. Thus, optimization remains a challenging research issue, especially in situation large-scale data which arouse scalability as well. To improve both performance QoS-aware composition, this paper proposes scalabl...