Isabel M. Ribeiro

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In this paper, we discuss the Eigenvalue Complementarity Problem (EiCP) where at least one of its defining matrices is asymmetric. A sufficient condition for the existence of a solution to the EiCP is established. The EiCP is shown to be equivalent to finding a global minimum of an appropriate merit function on a convex set Ω defined by linear constraints.(More)
In this paper we analyze the fundamental aspects of the construction of indoor maps suitable for their u s e i n n a vigation tasks by a mobile robot. We highlight the limitations inherent t o the use of a priori maps. We show the fundamental problems related to the simultaneous construction of the map and the localization of the robot within this map. We(More)
The Eigenvalue Complementarity Problem (EiCP) finds important applications in different areas of science and engineering and differs from the traditional Eigenvalue Problem on the existence of nonnegative variables and complementarity constraints between pairs of variables. In this talk the EiCP is first introduced together with some of its extensions and(More)
In this paper a branch-and-bound algorithm is proposed for finding a global minimum to a Mathematical Programming Problem with Complementarity (or Equilibrium) Constraints (MPECs), which incorporates disjunctive cuts for computing lower bounds and employs a Complementarity Active-Set Algorithm for computing upper bounds. Computational results for solving(More)
In this paper, an algorithm for solving a mathematical programming problem with complementarity (or equilibrium) constraints (MPEC) is introduced, which uses the active-set methodology while maintaining the complementarity restrictions throughout the procedure. Finite convergence of the algorithm to a strongly stationary point of the MPEC is established(More)
This paper proposes an architecture to achieve cooperative behaviour among a set of robotic devices. The architecture, with a pure reactive nature privileges the use of local decision mechanisms instead of centralized ones. The performance assessment for the execution of a class of tasks common in the operation of mobile manipulators is made via a(More)
The HIV-1 protein Rev controls a critical step in viral replication by mediating the nuclear export of unspliced and singly-spliced viral mRNAs. Multiple Rev subunits assemble on the Rev Response Element (RRE), a structured region present in these RNAs, and direct their export through the Crm1 pathway. Rev-RRE assembly occurs via several Rev oligomerization(More)
In this paper, an algorithm for solving a Mathematical Programming Problem with Complementarity (or Equilibrium) Constraints (MPEC) is introduced, which uses the active-set methodology while maintaining the complementarity restrictions throughout the procedure. Finite convergence of the algorithm to a stationary point of the MPEC is established under(More)