A procedure is described, based on a theorem of Post, for determining the nonredundant complete sets of logical functions. Kudielka and Oliva's determination of these functions for two and three variables was verified by means of this procedure in less than a minute of computer time. The procedure requires the computation of irredundant coverings, and novel features of the algorithm which was u...

Ordinary differential equations (ODEs) are ubiquitous when modeling continuous dynamics. Classical numerical methods compute approximations of the solution, however without any guarantees on the quality of the approximation. Nevertheless, methods have been developed that are supposed to compute enclosures of the solution. In this paper, we demonstrate that enclosures of the solution can be veri...

Two fast algorithms for numerically computing an interval matrix containing the solvent of the quadratic matrix equation AX2+BX+C = 0 with square matrices A, B, C and X are proposed. These algorithms require only cubic complexity, verify the uniqueness of the contained solvent, and do not involve iterative process. Let X̃ be a numerical approximation to the solvent. The first and second algorith...

A parallel version of the self-verified method for solving linear systems was presented in [16, 15]. In this research we propose improvements aiming at a better performance. The idea is to implement an algorithm that uses technologies as MPI communication primitives associated to libraries as LAPACK, BLAS and C-XSC, aiming to provide both self-verification and speed-up at the same time. The alg...

Transactional objects combine the performance of classical concurrent with high-level programmability transactional memory. However, verifying correctness is tricky, requiring reasoning simultaneously about objects, which guarantee atomicity individual methods—the property known as linearizability—and software-transactional-memory libraries, user-defined sequences method calls—or serializabilit...

Java has demonstrated the utility of type systems for mobile code, and in particular their use and implications for security. Security properties rest on the fact that a well-typed Java program (or the corresponding verified bytecode) cannot cause certain kinds of damage. In this paper we provide a type system for mobile computation, that is, for computation that is continuously active before a...