We show how to automatically construct and refine rectangular abstractions of systems of linear differential equations. From a hybrid automaton whose dynamics are given by a system of linear differential equations, our method computes automatically a sequence of rectangular hybrid automata that are increasingly precise overapproximations of the original hybrid automaton. We prove an optimality ...

It is well-known that multidimensional indices are efficient to improve the query performance on relational data. As one successful multi-dimensional index structure, R*-tree, a famous member of the R-tree family, is very popular. The clustering pattern of the objects (i.e., tuples in relational tables) among R*-tree leaf nodes is one of the deceive factors on performance of range queries, a po...

Prioritization of equipment is an important factor for decision making to optimize maintenance management in Reliability Centered Maintenance (RCM). Many factors must be considered as part of the prioritization of equipment for maintenance activities. Consequently, evaluation procedures involve several objectives and it is often necessary to compromise among conflicting tangible and intangible ...

We analyze several examples of switched linear circuits and a switched spring–mass system to illustrate the physical manifestations of regressivity and nonregressivity for discrete and continuous time systems as well as hybrid discrete/continuous systems from a time scales perspective. These examples highlight the role that nonregressivity plays in modeling and applications, and they point out ...

Spectrum sensing is a key enabling functionality in a cognitive radio (CR) network. The fusion problem of cooperative spectrum sensing, for a cognitive radio network equipped with multi-antennas at its base-station, is considered in this paper. The base-station equipped with multi-antennas act as a fusion center which can attain not only the soft information (average power) by its multi-antenna...

This paper presents an HMM-driven hybrid speech synthesis approach in which unit selection concatenative synthesis is used to improve the quality of the statistical system using a Local Minimum Generation Error (LMGE) during the synthesis stage. The idea behind this approach is to combine the robustness due to HMMs with the naturalness of concatenated units. Unlike the conventional hybrid appro...

An approach hybrid optical-computational criterion to generate an adaptive refinement mesh to be used in mechanical structure analysis with Finite Element Method (FEM) is proposed. The numerical error to determine the refinement zones in adaptive meshing is substituted for an experimental weight function. Experimental optical phase map is used to define this weight function. This criterion perm...