We present an algorithm for the two-dimensional translational containmentproblem: nd translations for k polygons (with up tom vertices each) which place them inside a polygonal container (with n vertices) without overlapping. The polygons and container may be nonconvex. The containment algorithm consists of new algorithms for restriction, evaluation, and subdivision of two-dimensional con gurat...

BACKGROUND Invasive meningococcal disease (IMD) is a serious disease with a rapid onset, high mortality rate, and risk of long-term complications. Numerous reports in the literature conclude that IMD outbreaks are associated with substantial costs to society and significant burden on communities due to the cost associated with the prevention of secondary cases. OBJECTIVE To systematically rev...

The study of the containment of conjunctive queries containing inequalities (denoted inequality queries in this paper) was a thoroughly studied and long standing problem. In [3], we offered an exact condition, along with a procedure, to test query containment of this type of queries, using the idea of canonical databases. In this work, we present a different approach that is sensibly more effic...

BACKGROUND Urban containment policies attempt to manage the location, character, and timing of growth to support a variety of goals such as compact development, preservation of greenspace, and efficient use of infrastructure. Despite prior research evaluating the effects of urban containment policies on land use, housing, and transportation outcomes, the public health implications of these poli...

This technical note presents the ubiquitous problem of query containment for conjunctive queries (an NP-complete problem), and an elegant implementation CQCP of Conjunctive Query Containment in Prolog, in just 7 lines of code. We also describe two important applications of conjunctive query containment: semantic query optimization and minimization. The latter can be implemented by another conci...