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991.
Juan L. Mata-Machuca Rafael Martínez-Guerra 《Computers & Mathematics with Applications》2012,63(6):1072-1078
In this paper we deal with the observer-based asymptotic synchronization problem for a class of chaotic oscillators. Some results based on a differential algebraic approach are used in order to determine the algebraic observability of unknown variables. The strategy consists of proposing a slave system (observer) which tends to follow asymptotically the master system. The methodology is tested in the real-time asymptotic synchronization of the Colpitts oscillator by means of a proportional reduced order observer (PROO) of free-model type. 相似文献
992.
Ontology-based user profile learning 总被引:4,自引:4,他引:0
Personal agents gather information about users in a user profile. In this work, we propose a novel ontology-based user profile
learning. Particularly, we aim to learn context-enriched user profiles using data mining techniques and ontologies. We are
interested in knowing to what extent data mining techniques can be used for user profile generation, and how to utilize ontologies
for user profile improvement. The objective is to semantically enrich a user profile with contextual information by using
association rules, Bayesian networks and ontologies in order to improve agent performance. At runtime, we learn which the
relevant contexts to the user are based on the user’s behavior observation. Then, we represent the relevant contexts learnt
as ontology segments. The encouraging experimental results show the usefulness of including semantics into a user profile
as well as the advantages of integrating agents and data mining using ontologies. 相似文献
993.
A multi-objective evolutionary algorithm for an effective tuning of?fuzzy logic controllers in?heating, ventilating and air conditioning systems 总被引:5,自引:5,他引:0
This paper focuses on the use of multi-objective evolutionary algorithms to develop smartly tuned fuzzy logic controllers
dedicated to the control of heating, ventilating and air conditioning systems, energy performance, stability and indoor comfort
requirements. This problem presents some specific restrictions that make it very particular and complex because of the large
time requirements needed to consider multiple criteria (which enlarge the solution search space) and the long computation
time models required in each evaluation. 相似文献
994.
A novel split-and-merge algorithm for hierarchical clustering of Gaussian mixture models 总被引:2,自引:2,他引:0
Branislav Popovi? Marko Janev Darko Pekar Nik?a Jakovljevi? Milan Gnjatovi? Milan Se?ujski Vlado Deli? 《Applied Intelligence》2012,37(3):377-389
The paper presents a novel split-and-merge algorithm for hierarchical clustering of Gaussian mixture models, which tends to improve on the local optimal solution determined by the initial constellation. It is initialized by local optimal parameters obtained by using a baseline approach similar to k-means, and it tends to approach more closely to the global optimum of the target clustering function, by iteratively splitting and merging the clusters of Gaussian components obtained as the output of the baseline algorithm. The algorithm is further improved by introducing model selection in order to obtain the best possible trade-off between recognition accuracy and computational load in a Gaussian selection task applied within an actual recognition system. The proposed method is tested both on artificial data and in the framework of Gaussian selection performed within a real continuous speech recognition system, and in both cases an improvement over the baseline method has been observed. 相似文献
995.
996.
997.
Adalberto Llarena Jesus Savage Angel Kuri Boris Escalante-Ramírez 《Journal of Intelligent and Robotic Systems》2012,66(1-2):75-109
This paper proposes an approach that solves the Robot Localization problem by using a conditional state-transition Hidden Markov Model (HMM). Through the use of Self Organized Maps (SOMs) a Tolerant Observation Model (TOM) is built, while odometer-dependent transition probabilities are used for building an Odometer-Dependent Motion Model (ODMM). By using the Viterbi Algorithm and establishing a trigger value when evaluating the state-transition updates, the presented approach can easily take care of Position Tracking (PT), Global Localization (GL) and Robot Kidnapping (RK) with an ease of implementation difficult to achieve in most of the state-of-the-art localization algorithms. Also, an optimization is presented to allow the algorithm to run in standard microprocessors in real time, without the need of huge probability gridmaps. 相似文献
998.
Peter Sussner Estev?o L. Esmi Ivan Villaverde Manuel Gra?a 《Journal of Mathematical Imaging and Vision》2012,42(2-3):134-149
Many well-known fuzzy associative memory (FAM) models can be viewed as (fuzzy) morphological neural networks (MNNs) because they perform an operation of (fuzzy) mathematical morphology at every node, possibly followed by the application of an activation function. The vast majority of these FAMs represent distributive models given by single-layer matrix memories. Although the Kosko subsethood FAM (KS-FAM) can also be classified as a fuzzy morphological associative memory (FMAM), the KS-FAM constitutes a two-layer non-distributive model. In this paper, we prove several theorems concerning the conditions of perfect recall, the absolute storage capacity, and the output patterns produced by the KS-FAM. In addition, we propose a normalization strategy for the training and recall phases of the KS-FAM. We employ this strategy to compare the error correction capabilities of the KS-FAM and other fuzzy and gray-scale associative memories in terms of some experimental results concerning gray-scale image reconstruction. Finally, we apply the KS-FAM to the task of vision-based self-localization in robotics. 相似文献
999.
1000.
Luis Antón-Canalís Mario Hernández-Tejera Elena Sánchez-Nielsen 《Pattern recognition》2012,45(9):3125-3130
A straightforward algorithm that computes distance maps from unthresholded magnitudes is presented, suitable for still images and video sequences. While results on binary images are similar to classic Euclidean Distance Transforms, the proposed approach does not require a binarization step. Thus, no thresholds are needed and no information is lost in intermediate classification stages. Experiments include the evaluation of spatial and temporal coherence of distance map values, showing better results in both measurements than those obtained with Sobel or Deriche gradients and classic chessboard distance transforms. 相似文献