Isabel M. M. P. Ribeiro

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In this paper we analyze the fundamental aspects of the construction of indoor maps suitable for their use in navigation tasks by a mobile robot We highlight the limitations inherent to 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 describe(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)
Samples of blue wall paint layers from selected 15th to 18th century religious mural paintings from southern Portugal (Alentejo) have been analyzed using a multi-analytical methodology involving the combination of in situ visible spectro-colorimetry with microanalytical techniques such as optical and scanning electron microscopy and Raman spectroscopy. In(More)
The detection and classification of moving objects is a key task in many control systems. This paper presents a solution for this problem based on a laser range scanner. The method can be summarized as follows. A set of 3D data points on the object surface is obtained using the scanner. A small number of features is then computed to represent the object(More)
This paper proposes a new path optimization method to improve feasibility and optimality of rough collision-free paths provided by global planners. Inspired on the dynamics of rigid bodies, this method redefines the elastic bands framework to explicitly handle vehicle geometric constraints and explore the high maneuvering ability of rhombic vehicles. The(More)
The ITER Remote Handling (RH) Maintenance System is a key component in ITER operation both for scheduled maintenance and for unexpected situations. It is a complex collection and integration of numerous systems, each one at its turn being the integration of diverse technologies into a coherent, space constrained, nuclearised design. This paper presents an(More)
This paper presents the distributed formation control of a multi-agent system using graph theory with emphasis on consensus and cooperation issues. The focal point is to achieve and maintain a formation from any initial condition, with and without a leader that the entire formation must follow. Our analysis framework is based on tools from algebraic graph(More)
Misalignments M. Isabel Ribeiro, Pedro Lima, Pedro Apar cio, Renato Ferreira Instituto Superior T ecnico/ Instituto de Sistemas e Rob otica, Av.Rovisco Pais 1, P-1096 Lisboa CODEX, PORTUGAL Tel: 351 1 8418059, Fax: 351 1 8418291, email: Abstract|This paper presents a study on the docking of a mobile platform to a docking port where six(More)