61 resultados para Computing Classification Systems
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This study explores, in 3 steps, how the 3 main library classification systems, the Library of Congress Classification, the Dewey Decimal Classification, and the Universal Decimal Classification, cover human knowledge. First, we mapped the knowledge covered by the 3 systems. We used the “10 Pillars of Knowledge: Map of Human Knowledge”, which comprises 10 pillars, as an evaluative model. We mapped all the subject-based classes and subclasses that are part of the first 2 levels of the 3 hierarchical structures. Then, we zoomed into each of the 10 pillars and analyzed how the three systems cover the 10 knowledge domains. Finally, we focused on the 3 library systems. Based on the way each one of them covers the 10 knowledge domains, it is evident that they failed to adequately and systematically present contemporary human knowledge. They are unsystematic and biased, and, at the top 2 levels of the hierarchical structures, they are incomplete.
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The process of knowledge representation as well as its procedures or tools and its products are not neutral in terms of values; instead they imply moral values. In this context, bias in representation related to prejudice and discrimination, to gender issues, to dicotomic categorization in classification systems or in thesauri and to lack of cultural warrant may arise. Concerning the problem of bias in indexing languages, starting from the initial theoretical reflexions of Brey (1999), Berman (1993), Olson (1998; 2002), Lopez-Huertas Perez & Torres Ramirez (2005), Guimaraes (2006), Hjorland (2008) and Milani et al. (2009), the proposal is to present a preliminary categorization aiming at facilitating the identification of bias concerning feminine issues in indexing languages, to offer a contribution to the theoretical universe of the specific questions of knowledge organization and to present a theme to be discussed by educators and professionals in the areas of cataloging, classification and indexing. If in a society which intends to be politically correct, social attitudes towards stigmatized citizens should be modified, then, the universe of indexing languages, taken as tools of knowledge representation, is a fertile field to sow this reflexion.
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This article analyzes the specific features and processes of indexing and classification performed in school libraries to process and retrieve information from their collections. Subject languages used in Spanish, Portuguese and Brazilian Portuguese school libraries are also analyzed. To achieve this goal, the concept of school library was analyzed, its function was studied and the techniques and tools that allow the information organization were examined. Among the tools, we studied the Subject Headings Lists for children and juveniles'books and the Subject Headings List for public libraries, the Universal Decimal Classification System (paperback edition) or the classification by fields of interest and specialized thesauri like the Tesauro de la Educacion UNESCO-OIE and the TesauroEuropeo de la Educacion.
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Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)
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Mobile robots need autonomy to fulfill their tasks. Such autonomy is related whith their capacity to explorer and to recognize their navigation environments. In this context, the present work considers techniques for the classification and extraction of features from images, using artificial neural networks. This images are used in the mapping and localization system of LACE (Automation and Evolutive Computing Laboratory) mobile robot. In this direction, the robot uses a sensorial system composed by ultrasound sensors and a catadioptric vision system equipped with a camera and a conical mirror. The mapping system is composed of three modules; two of them will be presented in this paper: the classifier and the characterizer modules. Results of these modules simulations are presented in this paper.
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This paper presents two approaches of Artificial Immune System for Pattern Recognition (CLONALG and Parallel AIRS2) to classify automatically the well drilling operation stages. The classification is carried out through the analysis of some mud-logging parameters. In order to validate the performance of AIS techniques, the results were compared with others classification methods: neural network, support vector machine and lazy learning.
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Internet access by wireless networks has grown considerably in recent years. However, these networks are vulnerable to security problems, especially those related to denial of service attacks. Intrusion Detection Systems(IDS)are widely used to improve network security, but comparison among the several existing approaches is not a trivial task. This paper proposes building a datasetfor evaluating IDS in wireless environments. The data were captured in a real, operating network. We conducted tests using traditional IDS and achieved great results, which showed the effectiveness of our proposed approach.
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Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)
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The increase of higher education offer is a basic need of developed and emerging countries. It requires increasing and ongoing investments. The offer of higher education, by means of Distance Learning, based on the Internet, is one of the most efficient manners for the massification of this offer, as it allows ample coverage and lower costs. In this scenario, we highlight Moodle, an open and low-cost environment for Distance Learning. Its utilization may be amplified through the adoption of an emerging Information and Communication Technology (ICT), Cloud Computing, which allows the virtualization of Moodle sites, cutting costs, facilitating management and increasing its service capacity. This article diffuses a public tool, opened and free, for automatic conversion of Moodle sites, such that these may be hosted on Azure: the Cloud Computing environment of Microsoft.
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The advantages offered by the electronic component light emitting diode ( LED) have caused a quick and wide application of this device in replacement of incandescent lights. However, in its combined application, the relationship between the design variables and the desired effect or result is very complex and it becomes difficult to model by conventional techniques. This work consists of the development of a technique, through artificial neural networks, to make possible to obtain the luminous intensity values of brake lights using LEDs from design data. (C) 2005 Elsevier B.V. All rights reserved.
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This paper presents an efficient neural network for solving constrained nonlinear optimization problems. More specifically, a two-stage neural network architecture is developed and its internal parameters are computed using the valid-subspace technique. The main advantage of the developed network is that it treats optimization and constraint terms in different stages with no interference with each other. Moreover, the proposed approach does not require specification of penalty or weighting parameters for its initialization.
Detection and Identification of Abnormalities in Customer Consumptions in Power Distribution Systems
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Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)
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This paper presents an interior point method for the long-term generation scheduling of large-scale hydrothermal systems. The problem is formulated as a nonlinear programming one due to the nonlinear representation of hydropower production and thermal fuel cost functions. Sparsity exploitation techniques and an heuristic procedure for computing the interior point method search directions have been developed. Numerical tests in case studies with systems of different dimensions and inflow scenarios have been carried out in order to evaluate the proposed method. Three systems were tested, with the largest being the Brazilian hydropower system with 74 hydro plants distributed in several cascades. Results show that the proposed method is an efficient and robust tool for solving the long-term generation scheduling problem.
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This work presents a methodology to analyze electric power systems transient stability for first swing using a neural network based on adaptive resonance theory (ART) architecture, called Euclidean ARTMAP neural network. The ART architectures present plasticity and stability characteristics, which are very important for the training and to execute the analysis in a fast way. The Euclidean ARTMAP version provides more accurate and faster solutions, when compared to the fuzzy ARTMAP configuration. Three steps are necessary for the network working, training, analysis and continuous training. The training step requires much effort (processing) while the analysis is effectuated almost without computational effort. The proposed network allows approaching several topologies of the electric system at the same time; therefore it is an alternative for real time transient stability of electric power systems. To illustrate the proposed neural network an application is presented for a multi-machine electric power systems composed of 10 synchronous machines, 45 buses and 73 transmission lines. (C) 2010 Elsevier B.V. All rights reserved.
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We study the existence of homoclic solutions for reversible Hamiltonian systems taking the family of differential equations u(iv) + au - u +f(u, b) = 0 as a model, where fis an analytic function and a, b real parameters. These equations are important in several physical situations such as solitons and in the existence of finite energy stationary states of partial differential equations, but no assumptions of any kind of discrete symmetry is made and the analysis here developed can be extended to others Hamiltonian systems and successfully employed in situations where standard methods fail. We reduce the problem of computing these orbits to that of finding the intersection of the unstable manifold with a suitable set and then apply it to concrete situations. We also plot the homoclinic values configuration in parameters space, giving a picture of the structural distribution and a geometrical view of homoclinic bifurcations. (c) 2005 Published by Elsevier B.V.