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Introducing a Robust and Efficient Stopping Criterion for MOEA's

  • Guerrero Madrid, José Luis
  • Martí, Luis
  • Berlanga de Jesús, Antonio
  • García, Jesús
  • Molina López, José Manuel
Proceedings of: IEEE World Congress on Computational Intelligence 2010 (WCCI 2010): IEEE Congress on Evolutionary Computation (CEC 2010). Barcelona, Spain, 18-23 July 2010., Soft computing methods, and Multi-Objective Evolutionary Algorithms (MOEAs) in particular, lack a general convergence criterion which prevents these algorithms from detecting the generation where further evolution will provide little improvements (or none at all) over the current solution, making them waste computational resources. This paper presents the Least Squares Stopping Criterion (LSSC), an easily configurable and implementable, robust and efficient stopping criterion, based on simple statistical parameters and residue analysis, which tries to introduce as few setup parameters as possible, being them always related to the MOEAs research field rather than the techniques applied by the criterion., This work was supported in part by Projects CICYT TIN2008-06742-C02-02/TSI, CICYT TEC2008-06732-C02-02/TEC, CAM CONTEXTS (S2009/TIC- 1485) and DPS2008-07029-C02-02, Publicado
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Ontological representation of time-of-flight camera data to support vision-based AmI

  • Serrano, Miguel Á.
  • Gómez Romero, Juan
  • Patricio Guisado, Miguel Ángel
  • García, Jesús
  • Molina, José M.
Proceedings of: 4th International Workshop on Sensor Networks and Ambient Intelligence, 19-23 March 2012, Lugano ( Switzerland), Recent advances in technologies for capturing video data have opened a vast amount of new application areas. Among them, the incorporation of Time-of-Flight (ToF) cameras on Ambient Intelligence (AmI) environments. Although theperformance of tracking algorithms have quickly improved, symbolic models used to represent the resulting knowledge have not yet been adapted for smart environments. This paper presents an extension of a previous system in the area of videobased AmI to incorporate ToF information to enhance sceneinterpretation. The framework is founded on an ontologybased model of the scene, which is extended to incorporate ToF data. The advantages and new features of the model are demonstrated in a Social Signal Processing (SSP) application., This work was supported in part by Projects CICYT TIN2011-28620-C02-01, CICYT TEC2011-28626-C02-02, CAM CONTEXTS (S2009/TIC-1485) and DPS2008-07029- C02-02., Publicado
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Finding an Evolutionarily Stable Strategy in Agent Reputation and Trust (ART) 2007 Competition

  • Carbó Rubiera, Javier Ignacio
  • Molina López, José Manuel
Proceedings of: 23rd International Conference on Industrial Engineering and Other Applications of Applied intelligent Systems, IEA/AIE 2010, Cordoba, Spain, June 1-4, 2010, Our proposal is to apply a Game Theoretic approach to the games played in Agent Reputation and Trust Final Competitions. Using such testbed, three international competitions were successfully carried out jointly with the last AAMAS international Conferences. The corresponding way to define the winner of such competitions was to run a game with all the participants (16). Our point is that such game does not represent a complete way to determine the best trust/reputation strategy, since it is not proved that such strategy is evolutionarily stable. Specifically we prove that when the strategy of the winner of the two first international competitions (2006 and 2007) becomes dominant, it is defeated by other participant trust strategies. Then we found out (through a repeated game definition) the right equilibrium of trust strategies that is evolutionarily stable. This kind of repeated game has to be taken into account in the evaluation of trust strategies, and this conclusion would improve the way trust strategies have to be compared., This work was supported in part by Projects CICYT TIN2008-06742-C02-02/ TSI, CICYT TEC2008-06732-C02-02/TEC, SINPROB, CAM MADRINET S-0505/TIC/0255 and DPS2008-07029-C02-02., Publicado
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Modeling Internet as a User-Adapted Speech Service

  • Griol Barres, David
  • Carbó Rubiera, Javier Ignacio
  • Molina López, José Manuel
Proceedings of: 7th International Conference, HAIS 2012, Salamanca, Spain, March 28-30th, 2012., The web has become the largest repository of multimedia information and its convergence with telecommunications is now bringing the benefits of web technology and hybrid artificial intelligence systems to hand-held devices. However, maximizing accessibility is not always the main objective in the design of web applications, specially if it is concerned with facilitating access for disabled people. This way, natural spoken conversation and multimodal conversational agents have been proposed as a solution to facilitate a more natural interaction with these kind of devices. In this paper, we describe a proposal to provide spoken access to Internet information that is valid not only to generate basic applications (e.g., web search engines), but also to develop dialog-based speech interfaces that facilitate a user-adapted access that enhances web services. We describe our proposal and detail several applications developed to provide evidences about the benefits of introducing speech to make the enormous web content accessible to all mobile phone users., Research funded by projects CICYT TIN2011-28620- C02-01, CICYT TEC2011-28626-C02-02,CAM CONTEXTS (S2009/TIC-1485), and DPS2008-07029-C02-02., Publicado
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Analysis of a sensor fusion hybrid solution for indoor/outdoor robot navigation

  • Martí, Enrique David
  • García, Jesús
  • Molina, José M.
Proceedings of: 5th ESA Workshop on Satellite Navigation Technologies and European Workshop on GNSS Signals and Signal Processing (NAVITEC 2010). Noordwij, Netherlands, 8-10 December 2010, Autonomous mobile robots need robust, flexible and accurate navigation algorithms. One approach consists in fusing as many information sources as possible, integrating measures from internal sensors with data obtained from external sensing entities. This work presents a solution for combined indoor/outdoor robot navigation, and analyzes some preliminary results in an outdoor environment using a Particle Filter for GPS/INS sensor fusion. Experiments are based in predesigned trajectories which have been simulated in first place and then reproduced using a robotic platform. As a concluding remark, some considerations about the use of Particle Filters and the differences between simulated and real data are presented, This work was supported in part by Projects ATLANTIDA, CICYT TIN2008-06742-C02-02/TSI, CICYT TEC2008- 06732-C02-02/TEC, SINPROB, CAM MADRINET S- 0505/TIC/0255 DPS2008-07029-C02-02., Publicado
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Neighborhood-based Regularization of Proposal Distribution for Improving Resampling Quality in Particle Filters

  • Martí, Enrique David
  • García, Jesús
  • Molina, José M.
Proceedings of: 14th International Conference on Information Fusion (FUSION 2011). Chicago, Illinois, USA 5-8 July 2011, Particle Filter is a sequential Montecarlo algorithm extensively used for solving estimation problems with non-linear and non-Gaussian features. In spite of its relative simplicity, it is known to suffer some undesired effects that can spoil its performance. Among these problems we can account the one known as sample depletion. This paper reviews the different causes of sample depletion and the many solutions proposed in the existing literature. It also introduces a new strategy for particle resampling which relies in a local linearization of the proposal distribution. The particles drawn using the proposed method are not affected by sample impoverishment and can indirectly lead to better results thanks to a reduction in the plant noise employed, as well to increased performance because of requiring a lower number of particles to achieve same results., Publicado
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Improving Multiple-Model Context-Aided Tracking through an Autocorrelation Approach

  • Martí, Enrique David
  • García, Jesús
  • Crassidis, John
Proceedings of: 15th International Conference on Information Fusion (FUSION), Singapore, 9-12 July 2012, This paper continues a previous work, where the context-aided tracker "ConTracker" was used to detect suspicious behaviors in maritime vehicle trajectories. ConTracker takes into account map-based contextual information - which includes water depth, shipping channels and areas/buildings with a high strategy value - to determine anomalies in ship trajectories. The different areas act as repellers or attractors that modify the expected trajectory of the tracked vessel. In the original scheme, a multiple-model adaptive estimator (MMAE) is used to estimate the noise parameters of the tracking system: sudden increases on the output reflect unexpected maneuvers - such as entering a forbidden area - that are translated as alarms. The work presented here shows the results obtained by implementing a generalized version of the multiple-model adaptive estimator (GMMAE). While the former approach uses information of the last cycle to update the weight/importance of each model, our proposal calculates a likelihood value based on the time-domain autocorrelation function of the last few indicators. GMMAE provides a much faster response, which ultimately leads to a general performance boost: alarms are faster and clearer. Compared with previous works, GMMAE is particularly effective returning back to normal state after an alarm has been raised: this results in alarms with a better defined duration. Results are presented over several simulated trajectories, featuring a variety of realistic anomalies which are correctly identified. They include direct comparison with the previous approach, for an objective demonstration of the achieved improvement., This work was supported in part by Projects CICYT TIN2011-28620-C02-01, CICYT TEC2011-28626-C02- 02, CAM CONTEXTS (S2009/TIC-1485) and DPS2008- 07029-C02-02., Publicado
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Distributed Active-Camera Control Architecture Based on Multi-Agent Systems

  • Luis Bustamante, Álvaro
  • Molina, José M.
  • Patricio Guisado, Miguel Ángel
Proceedings of: 10th Conference on Practical Applications of Agents and Multi-Agent Systems, Salamanca (Spain), 28-30 March 2012 (PAAMS`12), In this contribution a Multi-Agent System architecture is proposed to deal with the management of spatially distributed heterogeneous nets of sensors, specially is described the problem of Pan-Tilt-Zoom or active cameras. The design of surveillance multi-sensor systems implies undertaking to solve two related problems: data fusion and coordinated sensor-task management. Generally, proposed architectures for the coordinated operation of multiple sensors are based on centralization of management decisions at the fusion center. However, the existence of intelligent sensors capable of taking decisions brings the possibility of conceiving alternative decentralized architectures. This problem could be approached by means of a Multi-Agent System (MAS). In specific, this paper proposes a MAS architecture for automatically control sensors in video surveillance environments., This work was supported in part by Projects CICYT TIN2008-06742-C02-02/TSI, CICYT TEC2008-06732-C02-02/TEC, CAM CONTEXTS (S2009/ TIC-1485) and DPS2008- 07029-C02-02., Publicado
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Multicamera Action Recognition with Canonical Correlation Analysis and Discriminative Sequence Classification

  • Cilla, Rodrigo
  • Patricio Guisado, Miguel Ángel
  • Berlanga de Jesús, Antonio
  • Molina López, José Manuel
Proceedings of: 4th International Work-Conference on the Interplay Between Natural and Artificial Computation, IWINAC 2011, La Palma, Canary Islands, Spain, May 30 - June 3, 2011., This paper presents a feature fusion approach to the recognition of human actions from multiple cameras that avoids the computation of the 3D visual hull. Action descriptors are extracted for each one of the camera views available and projected into a common subspace that maximizes the correlation between each one of the components of the projections. That common subspace is learned using Probabilistic Canonical Correlation Analysis. The action classification is made in that subspace using a discriminative classifier. Results of the proposed method are shown for the classification of the IXMAS dataset., Publicado
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Air traffic trajectories segmentation based on time-series sensor data

  • Guerrero Madrid, José Luis
  • García, Jesús
  • Molina, José M.
Proyecto:


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