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Hybrid Optimal control for Aircraft Trajectory Design with a Variable Sequence of Modes

IFAC Proceedings Volumes 2011年第1期44卷 7238-7243页

作者： Maryam Kamgarpour Manuel Soler Claire J. Tomlin Alberto Olivares John Lygeros Department of Mechanical Engineering University of California at Berkeley USA Department of Statistics and Operations Research URJC 28933 Madrid Spain Department of Electrical Engineering and Computer Sciences University of California at Berkeley USA Automatic Control Laboratory ETH Zurich CH-8092 Switzerland

Abstract The problem of aircraft trajectory planning is formulated as a hybrid optimal control problem. The aircraft is modeled as a switched system, that is, a class of hybrid dynamical systems. The sequence of modes, the switching times, and the inputs for each mode are the control variables. An iterative bi-level optimization algorithm is employed to solve the optimal control problem. At the lower level, given a pre-defined sequence of flight modes, the optimal switching times and the input for each mode are determined. This is achieved by extending the continuous state to include the switching times and then solving a conventional optimal control problem for the extended state. At the higher level, the algorithm modifies the mode sequence in order to decrease the value of the cost function. We illustrate the utility of the problem formulation and the solution approach with two case studies in which short horizon aircraft trajectories are optimized in order to reduce fuel burn while avoiding hazardous weather.

关键词： Optimal control Hybrid systems Aircraft Operations Aircraft Trajectory Design

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Opposition-based shuffled PSO with passive congregation applied to FM matching synthesis

Opposition-based shuffled PSO with passive congregation appl...

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IEEE Congress on Evolutionary Computation

作者： Munoz, Daniel M. Llanos, Carlos H. Dos S. Coelho, Leandro Ayala-Rincon, Mauricio Department of Mechanical Engineering Automation and Control Group/GRACO University of Brasilia Brasilia D.F. Brazil Industrial and Systems Engineering Graduate Program LAS/PPGEPS Pontifical Catholic University of Parana Curitiba Parana Brazil Department of Computer Science and Mathematics University of Brasilia Brasilia D.F. Brazil

ISBN: (纸本)9781424478347

Synthesis of musical instruments or human voice is a time consuming process which requires theoretical and experimental knowledge about the synthesis engine. Commonly, performers need to deal with synthesizer interfaces and a process of trial and error for creating musical sounds similar to a target sound. This drawback can be overcome by adjusting automatically the synthesizer parameters using optimization algorithms. In this paper a hybrid particle swarm optimization (PSO) algorithm is proposed to solve the frequency modulation (FM) matching synthesis problem. The proposed algorithm takes advantage of a shuffle process for exchanging information between particles and applies the selective passive congregation and the opposition-based learning approaches to preserve swarm diversity. Both approaches for injecting diversity are based on simple operators, preserving the easy implementation philosophy of the particle swarm optimization. The proposed hybrid particle swarm optimization algorithm was validated for a three-nested FM synthesizer, which represents a 6-dimensional multimodal optimization problem with strong epistasis. Simulation results revealed that the proposed algorithm presented promising results in terms of quality of solutions. © 2011 IEEE.

关键词： Global optimization

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Robust H∞ filtering for uncertain 2-D continuous systems, based on a polynomially parameter-dependent Lyapunov function

Robust H∞ filtering for uncertain 2-D continuous systems, b...

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International Workshop on Multidimensional (nD) systems

作者： Chakir El-Kasri Abdelaziz Hmamed Teresa Alvarez Fernando Tadeo LESSI Department of Physics Faculty of Sciences University of Dhar EI Mehraz Fes-Atlas Morocco Department of Systems Engineering and Automatic Control University of Valladolid Valladolid Spain

The problem of robust H ∞ filtering for uncertain two-dimensional (2-D) continuous systems described by the Roesser state-space model is investigated when the parameter uncertainties are polytopic. A sufficient linear matrix inequality (LMI) condition for the existence of a 2-D continuous filter such that, for all admissible uncertainties, the error system is asymptotically stable, and the H ∞ norm of the transfer function from the noise signal to the estimation error is below a prespecified level. A sequence of standard LMI conditions that ensure the existence of homogeneous polynomially parameter-dependent (HPPD) matrices of arbitrary degree, that are solutions to the parameter-dependent LMIs is provided in terms of the vertices of the polytope. The proposed method includes results in the quadratic framework and the linearly parameter-dependent framework as special cases. Finally, an example is provided to demonstrate the effectiveness and advantages of the proposed filter design methodology.

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A Review of Energy Efficiency in Data Processing Centers

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Journal of Energy and Power engineering 2011年第4期5卷 361-372页

作者： C. Redondo A. Fern/mdez Castile and Leon Technological Center for Supercomputing （FCSC） Edificio CRAI- TIC Campus de Vegazana s/n University of Le6n E-24071-Lean Spain Electrical Engineering and Systems Engineering and Automatic Control Department Faculty of lndustrial and Computer Engineering University of Leon E-24071-Leon Spain

This article explores, through a case study, measures of energy efficiency in data processing centers. An analysis of this case demonstrates how the design criteria could improve the rate of consumption in IT centers, which is currently the second most contaminating industry on the planet, and is the responsible for 2% of CO2 emissions, surpassed only by the aeronautical industry. The present and future situation of IT center energy consumption and associated environmental effects is analyzed, and also looks at how state-of-the-art technology, correctly implemented, could ensure significant rationalization of data processing center energy consumption. The article will examine optimization techniques, specific problems and case studies.

关键词： Energy management data processing centers energy efficiency.

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Distributed Event-Based control for Interconnected Linear systems

Distributed Event-Based Control for Interconnected Linear Sy...

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IEEE Conference on Decision and control

作者： M. Guinaldo D. V. Dimarogonas K. H. Johansson J. Sanchez S. Dormido Department of Computer Science and Automatic Control Spanish University of Distance Education (UNED) Spain School of Electrical Engineering Royal Institute of Technology (KTH) Sweden

ISBN: (纸本)9781612848006

This paper presents a distributed event-based control strategy for a networked dynamical system consisting of N linear time-invariant interconnected subsystems. Each subsystem broadcasts its state over the network according to some triggering rules which depend on local information only. The system converges to an adjustable region around the equilibrium point under the proposed control design, and the existence of a lower bound for the broadcasting period is guaranteed. The effect of the coupling terms over the region of convergence and broadcasting period lower bound is analyzed, and a novel model-based approach is derived to reduce the communications. Simulation results show the effectiveness of the proposed approaches and illustrate the theoretical results.

关键词： design control equilibrium point Event-based broadcasting control strategy Linear system SUB-SYSTEM Lower bound Converge Distribute

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Ship's roll stabilization by anti-roll active tanks

Ship's roll stabilization by anti-roll active tanks

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OCEANS - Europe

作者： M. Haro R. Ferreiro F.J. Velasco Faculty of Nautical Sciences University of Cádiz Cadiz Spain Department Industrial Engineering University of A Coruña Spain Department Electronic Technology Systems Engineering and Automatic Control University of Cantabria Spain

This paper examines the control of the heeling angle of a ship in still waters based on the utilisation of anti-heeling tanks operated by pressurized air. The proposed objective attempts to reduce the list angle to a null value during the loading process in a fast ferry ship. A nonlinear adaptive controller has been designed as a means of counteracting the parameter inaccuracies that are involved in the nonlinear model. These are the linear and quadratic damping coefficients and the size of the cargo that is being handled. The design is based on a relatively new methodology, the backstepping procedure. With the objective of reducing the number of sensors a model reference based nonlinear observer has been introduced. The controller thus designed provides a robust control system under parametric uncertainties and state variable errors. The designed control implies an improvement on the actual systems based on the PID control implemented under programmable logic controllers (PLCs).

关键词： Marine vehicles Damping Torque Backstepping Stability criteria Atmospheric modeling

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Mass action realizations of reaction kinetic system models on various time scales

Mass action realizations of reaction kinetic system models o...

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作者： Hangos, K.M. Szederkényi, G. Process Control Research Group Computer and Automation Reseach Institute Kende u. 13-17 Budapest H-1111 Hungary Department of Electrical Engineering and Information Systems University of Pannonia Egyetem u. 10 Veszprém Hungary

Complex chemical reaction networks often exhibit different dynamic behaviour on different time scales. A combined approach is proposed in this work for determining physically meaningful mass action realizations of complex chemical reaction networks that describe its dynamic behaviour on different time scales. This is achieved by appropriately reducing the detailed overall mass action kinetic scheme using quasi steady state assumptions fit to the particular time scale, and then searching for an optimal realization using mixed integer linear programing. Furthermore, the relationship between the properties (reversibility, deficiency, stability) of the obtained realizations of the same system on different time scales are also investigated and related to the same properties of the detailed overall model. It is shown that the reduced models obtained by quasi steady state assumptions may show exotic nonlinear behaviour, such as oscillations, when the original detailed is globally asymptotically stable. The proposed methods are illustrated by using a simple Michaelis-Menten type reaction kinetic example. The simplified versions of the well known Brusselator model have also been investigated and presented as a case study. © Published under licence by IOP Publishing Ltd.

关键词： Reaction kinetics

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Ultimate boundedness and robust stabilization of bilinear discrete-time systems

Ultimate boundedness and robust stabilization of bilinear di...

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IEEE Conference on Decision and control

作者： Nikolaos Athanasopoulos George Bitsoris Marina Vassilaki Control Systems Laboratory Electrical and Computer Engineering Department University of Patras Rion 26500 Greece Department of Electrical Engineering of ASPAITE Maroussi Athens-Greece

ISBN: (纸本)9781612848006

In this paper nonlinear time-varying and bilinear discrete-time systems with additive bounded disturbances are considered. First, conditions guaranteeing uniform ultimate boundedness for time-varying nonlinear systems are established. Then, algebraic conditions ensuring the existence of polyhedral Lyapunov functions, uniform boundedness and positive invariance for closed-loop bilinear systems are obtained. Finally, these results are applied to various robust stabilization problems for bilinear systems subject to persistent additive disturbances. It is shown that these problems can be reduced to a single or a series of linear programming problems.

关键词： bilinear systems uniform ultimate boundedness bilinearity linear programming time varying

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Towards a Patient-Specific Model of Lung Volume Using Absolute Electrical Impedance Tomography (aEIT)

Towards a Patient-Specific Model of Lung Volume Using Absolu...

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4th International Joint Conference on Biomedical engineering systems and Technologies, BIOSTEC 2011

作者： Samuri, Suzani Mohamad Panoutsos, George Mahfouf, Mahdi Mills, G.H. Denaï, M. Brown, B.H. Department of Automatic Control and Systems Engineering University of Sheffield Mappin Street Sheffield S1 3JD United Kingdom Department of Critical Care and Anaesthesia Northern General Hospital Sheffield United Kingdom School of Science and Eng. Teesside University Middlesbrough United Kingdom Department of Medical Physics Royal Hallamshire Hospital Sheffield United Kingdom

Electrical Impedance Tomography (EIT), and in particular its application to pulmonary measurement, has been the subject of intensive research since its development in the early 1980s by Barber and Brown. One of the relatively recent advances in EIT is the development of an absolute EIT system (aEIT) which can estimate absolute values of lung resistivity and associated lung volumes. In this paper we present a new approach based on Computational Intelligence (CI) modelling to model the 'Resistivity - Lung Volume' relationship that will allow more accurate lung volume estimations using data from eight (8) healthy volunteers measured simultaneously via the Sheffield aEIT system and a Spirometer. The developed models show an improved accuracy in the prediction of lung volumes, as compared with the original Sheffield aEIT system. However the inter-individual differences observed in the subject-specific modelling behaviour of the 'Resistivity-Lung Volume' curves suggest that a model extension is needed, whereby the modelling structure auto-calibrates to account for subject (or patient-specific) inter-parameter variability. © Springer-Verlag Berlin Heidelberg 2013.

关键词： Electric impedance tomography

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Gradient-based classification and representation of features from volume data

Gradient-based classification and representation of features...

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International Conference on System Theory, control, and Computing (ICSTCC)

作者： Marius Gavrilescu Vasile Manta Eduard Gröller Technical University of Iasi Romania Vienna University of Technology Austria Faculty of Automatic Engineering and Computer Control Technical University of Iasi Romania Computer Science Department University of Bergen Norway

The extraction and representation of information from volume data are important research avenues in computer-based visualization. The interpretation of three- or multi-dimensional data from various scanning devices is important to medical imaging, diagnosis and treatment, reliability and sustainability analyses in various industrial branches, and, in more general terms, information visualization. In this paper, we present several approaches for the classification and representation of relevant information from volume data sets. The techniques are based on the gradient vector, a property directly derived from the original volume data. We show how this property can be computed and subsequently used for classification through gradient-based one- and multi-dimensional transfer functions, as well as for the enhancement of surface features. The described techniques are illustrated through images generated using our volume rendering framework, from Computed Tomography (CT) and Magnetic Resonance Imaging (MRI) data sets. The resulting images show how gradient-based techniques are suited for improved volume classification and the better extraction of meaningful information.

关键词： Transfer functions Image color analysis Rendering (computer graphics) Computed tomography Magnetic resonance imaging Skin Support vector machine classification

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