Ocampo-Martinez C.,Polytechnic University of Catalonia |
Barcelli D.,University of Siena |
Puig V.,Polytechnic University of Catalonia |
Bemporad A.,Institute for Advanced Studies Lucca
IET Control Theory and Applications | Year: 2012
A hierarchical and decentralised model predictive control (DMPC) strategy for drinking water networks (DWN) is proposed. The DWN is partitioned into a set of subnetworks using a partitioning algorithm that makes use of the topology of the network, historic information about the actuator usage and heuristics. A suboptimal DMPC strategy was derived, which consists in a set of MPC controllers, whose prediction model is a plant partition, where each element solves its control problem in a hierarchical order. A comparative simulation study between centralised MPC (CMPC) and DMPC approaches is developed using a case study, which consists in an aggregate version of the Barcelona DWN. Results have shown the effectiveness of the proposed DMPC approach in terms of the scalability of computations with an acceptable admissible loss of performance in all the considered scenarios. © 2011 The Institution of Engineering and Technology.
de Montis A.,University of Sassari |
Caschili S.,University College London |
Chessa A.,Complex Systems Computational Laboratory |
Chessa A.,University of Rome La Sapienza |
Chessa A.,Institute for Advanced Studies Lucca
European Physical Journal: Special Topics | Year: 2013
A major issue for policy makers and planners is the definition of "ideal" regional partitions, i. e. the delimitation of sub-regional domains showing a sufficient level of homogeneity with respect to some specific territorial features. In this paper, we compare some intermediate body partitions of Sardinia, Italy, with patterns that emerge from the workers and students' commuting. We apply grouping methodologies based on the characterization of Sardinian commuting system as a complex weighted network. We adopt an algorithm based on the maximization of the weighted modularity of this network and detect productive basins composed by municipalities with degree of cohesiveness in terms of commuters' flows. The results of this study lead us to conclude that the recently instituded provinces in Sardinia have been designed -even unconsciously- as labour basins of municipalities with similar commuting behaviour. © 2013 EDP Sciences and Springer.
De Nicola R.,Institute for Advanced Studies Lucca |
Ferrari G.,University of Pisa |
Loreti M.,University of Florence |
Pugliese R.,University of Florence
Lecture Notes in Computer Science (including subseries Lecture Notes in Artificial Intelligence and Lecture Notes in Bioinformatics) | Year: 2013
SCEL is a new language specifically designed to model autonomic components and their interaction. It brings together various programming abstractions that permit to directly represent knowledge, behaviors and aggregations according to specific policies. It also supports naturally programming self-awareness, context-awareness, and adaptation. In this paper, we first present design principles, syntax and operational semantics of SCEL. Then, we show how a dialect can be defined by appropriately instantiating the features of the language we left open to deal with different application domains and use this dialect to model a simple, yet illustrative, example application. Finally, we demonstrate that adaptation can be naturally expressed in SCEL. © 2013 Springer-Verlag Berlin Heidelberg.
Bruni R.,University of Pisa |
Gadducci F.,University of Pisa |
Lluch Lafuente A.,Institute for Advanced Studies Lucca
Lecture Notes in Computer Science (including subseries Lecture Notes in Artificial Intelligence and Lecture Notes in Bioinformatics) | Year: 2010
We define an algebraic theory of hierarchical graphs, whose axioms characterise graph isomorphism: two terms are equated exactly when they represent the same graph. Our algebra can be understood as a high-level language for describing graphs with a node-sharing, embedding structure, and it is then well suited for defining graphical representations of software models where nesting and linking are key aspects. © 2010 Springer-Verlag Berlin Heidelberg.
Bernardini D.,University of Trento |
Bemporad A.,Institute for Advanced Studies Lucca
Automatica | Year: 2012
Wireless sensor networks (WSNs) are becoming fundamental components of modern control systems due to their flexibility, ease of deployment and low cost. However, the energy-constrained nature of WSNs poses new issues in control design; in particular the discharge of batteries of sensor nodes, which is mainly due to radio communications, must be taken into account. In this paper we present a novel transmission strategy for communication between controller and sensors which is intended to minimize the data exchange over the wireless channel. Moreover, we propose an energy-aware control technique for constrained linear systems based on explicit model predictive control (MPC), providing closed-loop stability in the presence of disturbances. The presented control schemes are compared to traditional MPC techniques. The results show the effectiveness of the proposed energy-aware approach, which achieves a profitable trade-off between energy savings and closed-loop performance. © 2011 Elsevier Ltd. All rights reserved.