In this paper, we propose a novel type of probabilistic threshold top-k queries on uncertain data, and give an exact algorithm. More details can be found in [4]. I. PROBABILISTIC THRESHOLD TOP-k QUERIES We consider uncertain data in the possible worlds semantics model [1], [5], [7], which is also adopted by some recent studies on uncertain data processing, such as [8], [2], [6]. Generally, an u...

The well known Andrews-Curtis Conjecture [2] is still open. In this paper, we establish its finite version by describing precisely the connected components of the Andrews-Curtis graphs of finite groups. This finite version has independent importance for computational group theory. It also resolves a question asked in [5] and shows that a computation in finite groups cannot lead to a counterexam...

This paper describes the use of a concept hierarchy for improving the results of association rule mining. Given a large set of tuples with demographic information and personal interest information, association rules can be derived, that associate ages and gender with interests. However, there are two problems. Some data sets are too sparse for coming up with rules with high support. Secondly, s...

In this paper, we propose a new algorithm to establish Generalized Arc Consistency (GAC) on positive table constraints, i.e. constraints defined in extension by a set of allowed tuples. Our algorithm visits the lists of valid and allowed tuples in an alternative fashion when looking for a support (i.e. a tuple that is both allowed and valid). It is then able to jump over sequences of valid tupl...

Given a multi-dimensional dataset of tuples, skyline computation returns a subset of tuples that are not dominated by any other tuples when all dimensions are considered together. Conventional skyline computation, however, is inadequate to answer various queries that need to analyze not just individual tuples of a dataset but also their combinations. In this paper, we study group skyline comput...

In this paper, we show that if p is a prime and ifA = {a1, a2, . . . , am} is a set of positive integers with the property that aiaj +p is a perfect square for all 1 ≤ i < j ≤ m, then m < 3 · 2168. More generally, when p is replaced by a squarefree integer n, the inequality m ≤ f(ω(n)) holds with some function f , where ω(n) is the number of prime divisors of n. We also give upper bounds for m ...

Grushko’s theorem [Mat. Sb. 8 (1940) 169–182] says that any generating tuple (g1, . . . , gm) of a free product H ∗K is Nielsen-equivalent to a tuple (h1, . . . , hl, kl+1, . . . , km) with hi ∈ H and ki ∈ K for all i. The hi and ki are clearly not unique. In this paper we address the extent of this non-uniqueness.

In this demo, we present PACKAGEBUILDER, a system that extends database systems to support package queries. A package is a collection of tuples that individually satisfy base constraints and collectively satisfy global constraints. The need for package support arises in a variety of scenarios: For example, in the creation of meal plans, users are not only interested in the nutritional content o...