We study the complexity of the model checking problem, for fixed models A, over certain fragments L of first-order logic, obtained by restricting which of the quantifiers and boole...
Using a technique that Tverberg and Vrecica [TV93] discovered to give a surprisingly simple proof of Tverberg's theorem, we show the following extension of the centerpoint th...
Abdul Basit, Nabil H. Mustafa, Saurabh Ray, Sarfra...
We present the IteratedTverberg algorithm, the first deterministic algorithm for computing an approximate centerpoint of a set S Rd with running time subexponential in d. The alg...
r Numerical Abstractions6 Roberto Bagnaraa , Patricia M. Hillb , Enea Zaffanellaa aDepartment of Mathematics, University of Parma, Italy bSchool of Computing, University of Leeds, ...
Roberto Bagnara, Patricia M. Hill, Enea Zaffanella
We study the complexity and the I/O-efficient computation of flow on triangulated terrains. We present an acyclic graph, the descent graph, that enables us to trace flow paths in ...
Mark de Berg, Otfried Cheong, Herman J. Haverkort,...
our tree is an abstraction of a scalar field that encodes the nesting relationships of isosurfaces. We show how to use the contour tree to represent individual contours of a scala...