Data broadcasting provides an effective way to disseminate information in the wireless mobile environment using a broadcast channel. How to provide the service of the k nearest neighbors (kNN) search using data broadcasting is studied in this paper. Given a data set D and a query point p, the kNN search finds k data points in D closest to p. By assuming that the data is indexed by an R-tree, we...

Let K be a finite set of finite structures. We give a syntactic characterization of the property: every element of K is invective in ISP(K). We use this result to establish that 4 is invective in ISP(s) for every two-element algebra i. ?0. Introduction. Let K be a finite set of finite structures for a first-order language. In this paper we give a syntactic characterization (Theorem 4) of the pr...

Spatial indexing is a well researched field that benefited computer science with many outstanding results. Our effort in this paper can be seen as revisiting some outstanding contributions to spatial indexing, questioning some paradigms, and designing an access method with globally improved performance characteristics. In particular, we argue that dynamic R-tree construction is a typical cluste...

In this paper, we are starting a systematic analysis of a class of symmetric polynomials which, in full generality,was introduced in [Sa]. The main features of these functions are that they are defined by vanishing conditions and that they are nonhomogeneous. They depend on several parameters, but we are studying mainly a certain subfamily which is indexed by one parameter, r. As a special case...

Let K and X be compact plane sets such that K X. Let P(K)be the uniform closure of polynomials on K. Let R(K) be the closure of rationalfunctions K with poles o K. Dene P(X;K) and R(X;K) to be the uniformalgebras of functions in C(X) whose restriction to K belongs to P(K) and R(K),respectively. Let CZ(X;K) be the Banach algebra of functions f in C(X) suchthat fjK = 0. In this paper, we show th...