13 research outputs found

    Analysis using Adaptive Tree Structured Clustering Method for Medical Data of Patients with Coronary Heart Disease

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    It is known that the classification of medical data is difficult problem because the medical data has ambiguous information or missing data. As a result, the classification method that can handle ambiguous information or missing data is necessity. In this paper we proposed an adaptive tree structure clustering method in order to clarify clustering result of selforganizing feature maps. For the evaluating effectiveness of proposed clustering method for the data set with ambiguous information, we applied an adaptive tree structured clustering method for classification of coronary heart disease database. Through the computer simulation we showed that the proposed clustering method was effective for the ambiguous data set

    Clustering Of Complex Shaped Data Sets Via Kohonen Maps And Mathematical Morphology

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    Clustering is the process of discovering groups within the data, based on similarities, with a minimal, if any, knowledge of their structure. The self-organizing (or Kohonen) map (SOM) is one of the best known neural network algorithms. It has been widely studied as a software tool for visualization of high-dimensional data. Important features include information compression while preserving topological and metric relationship of the primary data items. Although Kohonen maps had been applied for clustering data, usually the researcher sets the number of neurons equal to the expected number of clusters, or manually segments a two-dimensional map using some a priori knowledge of the data. This paper proposes techniques for automatic partitioning and labeling SOM networks in clusters of neurons that may be used to represent the data clusters. Mathematical morphology operations, such as watershed, are performed on the U-matrix, which is a neuron-distance image. The direct application of watershed leads to an oversegmented image. It is used markers to identify significant clusters and homotopy modification to suppress the others. Markers are automatically found by performing a multi-level scan of connected regions of the U-matrix. Each cluster of neurons is a sub-graph that defines, in the input space, complex and nonparametric geometries which approximately describes the shape of the clusters. The process of map partitioning is extended recursively. Each cluster of neurons gives rise to a new map, which are trained with the subset of data that were classified to it. The algorithm produces dynamically a hierarchical tree of maps, which explains the cluster's structure in levels of granularity. The distributed and multiple prototypes cluster representation enables the discoveries of clusters even in the case when we have two or more non-separable pattern classes.43841627Vinod, V.V., Chaudhury, S., Mukherjee, J., Ghose, S., A connectionist approach for clustering with applications in image analysis (1994) IEEE Trans. Systems, Man & Cybernetics, 24 (3), pp. 356-384Costa, J.A.F., (1999) Automatic classification and data analysis by self-organizing neural networks, , Ph.D. Thesis. State University of Campinas, SP, BrazilEveritt, B.S., (1993) Cluster Analysis, , Wiley: New YorkKaufman, L., Rousseeuw, P., (1990) Finding Groups in Data: An Introduction to Cluster Analysis, , Wiley: New YorkSu, M.-C., Declaris, N., Liu, T.-K., Application of neural networks in cluster analysis (1997) Proc. of the 1997 IEEE Intl. Conf. on Systems, Man, and Cybernetics, pp. 1-6Kothari, R., Pitts, D., On finding the number of clusters (1999) Pattern Recognition Letters, 20, pp. 405-416Hardy, A., (1996) On the number of clusters. Computational Statistics and Data Analysis, 23, pp. 83-96Jain, A.K., Murty, M.N., Flynn, P.J., Data clustering: A review (1999) ACM Computing Surveys, 31 (3), pp. 264-323Ball, G., Hall, D., A clustering technique for summarizing multivariate data (1967) Behavioral Science, 12, pp. 153-155Bezdek, J.C., Pal, N.R., Some new indexes of cluster validity (1998) IEEE Transactions on Systems, Man, and Cybernetics (Part B), 28, pp. 301-315Haykin, S., (1999) Neural Networks: A Comprehensive Foundation, , 2nd edition, Prentice-Hall: New YorkKamgar-Parsi, B., Gualtieri, J.A., Devaney, J.E., Kamgar-Parsi, B., Clustering with neural networks (1990) Biological Cybernetics, 63, pp. 201-208Frank, T., Kraiss, K.-F., Kuhlen, T., Comparative analysis of fuzzy ART and ART-2A network clustering performance (1998) IEEE Trans. on Neural Networks, 9, pp. 544-559Kohonen, T., (1997) Self-Organizing Maps, , 2nd Ed., Springer-Verlag: BerlinUltsch, A., Self-Organizing Neural Networks for Visualization and Classification (1993) Information and Classification, pp. 301-306. , O. Opitz et al. (Eds)., Springer: BerlinGirardin, L., (1995) Cyberspace geography visualization, , heiwww.unige.ch/girardin/cgvGonzales, R.C., Woods, R.E., (1992) Digital Image Processing. Reading, , MA: Addison-WesleyBarrera, J., Banon, J., Lotufo, R., Mathematical Morphology Toolbox for the Khoros System (1994) Image Algebra and Morphological Image Processing V, 2300, pp. 241-252. , E. Dougherty et al. Eds. Proc. SPIESerra, J., (1982) Image Analysis and Mathematical Morphology, , Academic Press: LondonNajman, L., Schmitt, M., Geodesic Saliency of Watershed Contours and Hierarchical Segmentation (1996) IEEE Trans. on Pattern Analysis and Machine Intelligence, 18, pp. 1163-1173Bleau, A., Leon, L.J., Watershed-based segmentation and region merging Comp. Vis. Image Underst., 77, pp. 317-370Costa, J.A.F., Mascarenhas, N., Netto, M.L.A., Cell nuclei segmentation in noisy images using morphological watersheds (1997) Applications of Digital Image Processing XX., 3164, pp. 314-324. , A. Tescher Ed. Proc. of the SPIECosta, J.A.F., Netto, M.L.A., Estimating the Number of Clusters in Multivariate Data by Self-Organizing Maps (1999) International Journal of Neural Systems, 9 (3), pp. 195-202Costa, J.A.F., Netto, M.L.A., Cluster analysis using self-organizing maps and image processing techniques Proc. of the 1999 IEEE Intl. Conf. on Systems, Man, and Cybernetics, , Tokyo, JapanNakamura, E., Kehtarnavaz, N., Determining the number of clusters and prototype locations via multi-scale clustering (1998) Pattern Recognition Letters, 19, pp. 1265-1283Li, T., Tang, Y., Suen, S., Fang, L., Hierarchical classification and vector quantisation with neural trees (1993) Neurocomputing, 5, pp. 119-139Racz, J., Klotz, T., Knowledge representation by dynamic competitive learning techniques Proc. 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    Innehållsbaserad sökning av hierarkiska objekt med PicSOM

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    The amounts of multimedia content available to the public have been increasing rapidly in the last decades and it is expected to grow exponentially in the years to come. This development puts an increasing emphasis on automated content-based information retrieval (CBIR) methods, which index and retrieve multimedia based on its contents. Such methods can automatically process huge amounts of data without the human intervention required by traditional methods (e.g. manual categorisation, entering of keywords). Unfortunately CBIR methods do have a serious problem: the so-called semantic gap between the low-level descriptions used by computer systems and the high-level concepts of humans. However, by emulating human skills such as understanding the contexts and relationships of the multimedia objects one might be able to bridge the semantic gap. To this end, this thesis proposes a method of using hierarchical objects combined with relevance sharing. The proposed method can incorporate natural relationships between multimedia objects and take advantage of these in the retrieval process, hopefully improving the retrieval accuracy considerably. The literature survey part of the thesis consists of a review of content-based information retrieval in general and also looks at multimodal fusion in CBIR systems and how that has been implemented previously in different scenarios. The work performed for this thesis includes the implementation of hierarchical objects and multimodal relevance sharing into the PicSOM CBIR system. Also extensive experiments with different kinds of multimedia and other hierarchical objects (segmented images, web-link structures and video retrieval) were performed to evaluate the usefulness of the hierarchical objects paradigm. Keywords: content-based retrieval, self-organizing map, multimedia database

    Auto-adaptativité et topologie dans les cartes de Kohonen

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    Nous modifions l’algorithme non supervisé de Kohonen sur la base de considérations biologiques, dans le double intérêt d’améliorer ses performances de modélisation et d’enrichir sa valeur de modèle théorique d’auto-organisation neuronale. À chaque étape de nos recherches sur l’auto-adaptativité et la topologie des cartes de Kohonen, nous intégrons nos conclusions à un algorithme opérationnel : version normée, multirythmique et auto-instruite. Deux nouvelles fonctions sont introduites : l’Attractivité locale AintL inspirée du « Growing Neural Gas network »(GNG) et la Connaissance Cint, qui permettent de réduire l’erreur de modélisation jusqu’à 80% de l’erreur standard. L’extension du cadre classique d’étude de la topologie petit-monde, récemment décou- verte dans quantité de réseaux, à la théorie de l’information, nous permet par ailleurs de mettre en lumière le lien temporel entre structure (topologie) et fonction (apprentissage et connaissance) du système de neurones.Using biological understanding we have modified the unsupervised Kohonen algo- rithm, with two aims : to improve the performance of modelisation and to make this theoretical model of neural self-organisation more realistic. At various stages during our research into the auto-adaptivity and topology of Kohonen maps, we implemented our findings into practical algorithms creating normalised, multirhythmic and self-instructed versions. Two new functions are introduced : local attractivity AintL , inspired from Growing Neural Gas networks (GNG), and knowledge Cint. Using these, modelisation error is reduced by up to 80% of the standard error. Guided by recent work that shows small-world topologies exist in a large number of networks, we have extended this classic approach to information theory. This has highlighted the temporal link between structure (topology) and function (learning and knowledge) in the neural system

    Biased classification for relevance feedback in content-based image retrieval.

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    Peng, Xiang.Thesis (M.Phil.)--Chinese University of Hong Kong, 2007.Includes bibliographical references (leaves 98-115).Abstracts in English and Chinese.Abstract --- p.iAcknowledgement --- p.ivChapter 1 --- Introduction --- p.1Chapter 1.1 --- Problem Statement --- p.3Chapter 1.2 --- Major Contributions --- p.6Chapter 1.3 --- Thesis Outline --- p.7Chapter 2 --- Background Study --- p.9Chapter 2.1 --- Content-based Image Retrieval --- p.9Chapter 2.1.1 --- Image Representation --- p.11Chapter 2.1.2 --- High Dimensional Indexing --- p.15Chapter 2.1.3 --- Image Retrieval Systems Design --- p.16Chapter 2.2 --- Relevance Feedback --- p.19Chapter 2.2.1 --- Self-Organizing Map in Relevance Feedback --- p.20Chapter 2.2.2 --- Decision Tree in Relevance Feedback --- p.22Chapter 2.2.3 --- Bayesian Classifier in Relevance Feedback --- p.24Chapter 2.2.4 --- Nearest Neighbor Search in Relevance Feedback --- p.25Chapter 2.2.5 --- Support Vector Machines in Relevance Feedback --- p.26Chapter 2.3 --- Imbalanced Classification --- p.29Chapter 2.4 --- Active Learning --- p.31Chapter 2.4.1 --- Uncertainly-based Sampling --- p.33Chapter 2.4.2 --- Error Reduction --- p.34Chapter 2.4.3 --- Batch Selection --- p.35Chapter 2.5 --- Convex Optimization --- p.35Chapter 2.5.1 --- Overview of Convex Optimization --- p.35Chapter 2.5.2 --- Linear Program --- p.37Chapter 2.5.3 --- Quadratic Program --- p.37Chapter 2.5.4 --- Quadratically Constrained Quadratic Program --- p.37Chapter 2.5.5 --- Cone Program --- p.38Chapter 2.5.6 --- Semi-definite Program --- p.39Chapter 3 --- Imbalanced Learning with BMPM for CBIR --- p.40Chapter 3.1 --- Research Motivation --- p.41Chapter 3.2 --- Background Review --- p.42Chapter 3.2.1 --- Relevance Feedback for CBIR --- p.42Chapter 3.2.2 --- Minimax Probability Machine --- p.42Chapter 3.2.3 --- Extensions of Minimax Probability Machine --- p.44Chapter 3.3 --- Relevance Feedback using BMPM --- p.45Chapter 3.3.1 --- Model Definition --- p.45Chapter 3.3.2 --- Advantages of BMPM in Relevance Feedback --- p.46Chapter 3.3.3 --- Relevance Feedback Framework by BMPM --- p.47Chapter 3.4 --- Experimental Results --- p.47Chapter 3.4.1 --- Experiment Datasets --- p.48Chapter 3.4.2 --- Performance Evaluation --- p.50Chapter 3.4.3 --- Discussions --- p.53Chapter 3.5 --- Summary --- p.53Chapter 4 --- BMPM Active Learning for CBIR --- p.55Chapter 4.1 --- Problem Statement and Motivation --- p.55Chapter 4.2 --- Background Review --- p.57Chapter 4.3 --- Relevance Feedback by BMPM Active Learning . --- p.58Chapter 4.3.1 --- Active Learning Concept --- p.58Chapter 4.3.2 --- General Approaches for Active Learning . --- p.59Chapter 4.3.3 --- Biased Minimax Probability Machine --- p.60Chapter 4.3.4 --- Proposed Framework --- p.61Chapter 4.4 --- Experimental Results --- p.63Chapter 4.4.1 --- Experiment Setup --- p.64Chapter 4.4.2 --- Performance Evaluation --- p.66Chapter 4.5 --- Summary --- p.68Chapter 5 --- Large Scale Learning with BMPM --- p.70Chapter 5.1 --- Introduction --- p.71Chapter 5.1.1 --- Motivation --- p.71Chapter 5.1.2 --- Contribution --- p.72Chapter 5.2 --- Background Review --- p.72Chapter 5.2.1 --- Second Order Cone Program --- p.72Chapter 5.2.2 --- General Methods for Large Scale Problems --- p.73Chapter 5.2.3 --- Biased Minimax Probability Machine --- p.75Chapter 5.3 --- Efficient BMPM Training --- p.78Chapter 5.3.1 --- Proposed Strategy --- p.78Chapter 5.3.2 --- Kernelized BMPM and Its Solution --- p.81Chapter 5.4 --- Experimental Results --- p.82Chapter 5.4.1 --- Experimental Testbeds --- p.83Chapter 5.4.2 --- Experimental Settings --- p.85Chapter 5.4.3 --- Performance Evaluation --- p.87Chapter 5.5 --- Summary --- p.92Chapter 6 --- Conclusion and Future Work --- p.93Chapter 6.1 --- Conclusion --- p.93Chapter 6.2 --- Future Work --- p.94Chapter A --- List of Symbols and Notations --- p.96Chapter B --- List of Publications --- p.98Bibliography --- p.10

    Computer aided identification of biological specimens using self-organizing maps

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    For scientific or socio-economic reasons it is often necessary or desirable that biological material be identified. Given that there are an estimated 10 million living organisms on Earth, the identification of biological material can be problematic. Consequently the services of taxonomist specialists are often required. However, if such expertise is not readily available it is necessary to attempt an identification using an alternative method. Some of these alternative methods are unsatisfactory or can lead to a wrong identification. One of the most common problems encountered when identifying specimens is that important diagnostic features are often not easily observed, or may even be completely absent. A number of techniques can be used to try to overcome this problem, one of which, the Self Organizing Map (or SOM), is a particularly appealing technique because of its ability to handle missing data. This thesis explores the use of SOMs as a technique for the identification of indigenous trees of the Acacia species in KwaZulu-Natal, South Africa. The ability of the SOM technique to perform exploratory data analysis through data clustering is utilized and assessed, as is its usefulness for visualizing the results of the analysis of numerical, multivariate botanical data sets. The SOM’s ability to investigate, discover and interpret relationships within these data sets is examined, and the technique’s ability to identify tree species successfully is tested. These data sets are also tested using the C5 and CN2 classification techniques. Results from both these techniques are compared with the results obtained by using a SOM commercial package. These results indicate that the application of the SOM to the problem of biological identification could provide the start of the long-awaited breakthrough in computerized identification that biologists have eagerly been seeking.Dissertation (MSc)--University of Pretoria, 2011.Computer Scienceunrestricte

    Content-Based Image Retrieval Using Self-Organizing Maps

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    Modelling the locational determinants of house prices: neural network and value tree approaches

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    Tom Kauko's book comprises an analysis of the locational element in house prices. Locational features can increase or decrease the value of a house compared with a similar one elsewhere. So far, the problem of isolating this element has been well documented in the literatures on spatial housing market modelling and property value modelling. These lines of research usually use the economic equilibrium model as theoretical umbrella. Kauko's approach extends this conventional model towards involving problematic aspects such as multiple equilibria, institutions and diversified preferences. By doing so, Kauko argues that using one approach only is insufficient, and therefore he applies two different methods for the empirical part of the analysis. The first one is essentially a mass-appraisal approach based on neural network modelling that identifies segments, location, and omitted variables. The second one is a dis-aggregated approach based on multiattribute value tree modelling that encapsulates the behavioural element - perceptions, preferences, price/quality relationships, and agency effects. The results show the strengths and weaknesses of the new methods as tools for a variety of appraisal purpose
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