964 resultados para Data Warehousing Systems


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This work presents liquid-liquid experimental data for systems composed of sunflower seed oil, ethanol and water from 10 to 60 degrees C. The influence of process variables (temperature (T) and water concentration in the solvent (W)) on both the solvent content present in the raffinate (S(RP)) and extract (S(EP)) phases and the partition of free fatty acids (k(2)) was evaluated using the response surface methodology, where flash calculations were performed for each trial using the UNIQUAC equation. Water content in the solvent was the most important factor on the responses of S(EP) and k(2). Additionally, statistical analysis showed that the S(RP) was predominantly affected by temperature factor for low water content in the solvent. (c) 2009 Elsevier Ltd. All rights reserved.

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The DO experiment enjoyed a very successful data-collection run at the Fermilab Tevatron collider between 1992 and 1996. Since then, the detector has been upgraded to take advantage of improvements to the Tevatron and to enhance its physics capabilities. We describe the new elements of the detector, including the silicon microstrip tracker, central fiber tracker, solenoidal magnet, preshower detectors, forward muon detector, and forward proton detector. The uranium/liquid -argon calorimeters and central muon detector, remaining from Run 1, are discussed briefly. We also present the associated electronics, triggering, and data acquisition systems, along with the design and implementation of software specific to DO. (c) 2006 Elsevier B.V. All rights reserved.

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This article has the purpose to review the main codes used to detect and correct errors in data communication specifically in the computer's network. The Hamming's code and the Ciclic Redundancy Code (CRC) are presented as the focus of this article as well as CRC hardware implementation. Each code is reviewed in details in order to fill the gaps in the literature and to make it accessible to the computer science and engineering students as well as to anyone who may be interested in learning the technique to treat error in data communication.

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In a general way, in an electric power utility the current transformers (CT) are used to measurement and protection of transmission lines (TL) 1 The Power Line Carriers systems (PLC) are used for communication between electrical substations and transmission line protection. However, with the increasing use of optical fiber to communication (due mainly to its high data transmission rate and low signal-noise relation) this application loses potentiality. Therefore, other functions must be defined to equipments that are still in using, one of them is detecting faults (short-circuits) and transmission lines insulator strings damages 2. The purpose of this paper is to verify the possibility of using the path to the ground offered by the CTs instead of capacitive couplings / capacitive potential transformers to detect damaged insulators, since the current transformers are always present in all transmission lines (TL's) bays. To this a comparison between this new proposal and the PLC previous proposed system 2 is shown, evaluating the economical and technical points of view. ©2010 IEEE.

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In this work, we propose an innovative methodology to extend the construction of minimum and non-minimum delay perfect codes as a subset of cyclic division algebras over ℚ(ζ3), where the signal constellations are isomorphic to the hexagonal An 2 -rotated lattice, for any channel of any dimension n such that gcd{n, 3) = 1.

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Background: The World Health Organization (WHO) study entitled Suicide Trends in At-Risk Territories (START) is an international multisite initiative that aims to stimulate suicide research and prevention across different areas of the globe. A central component of the study is the development of registration systems for fatal and nonfatal suicidal behaviors. Aims: This paper provides an overview of the data collected on suicidal behaviors from the participating locations in the START study. Method: Descriptive statistics on the data are presented in terms of age, sex, and method. Results: Agreater proportion of suicide deaths occurred among males. In all areas except the Philippines more females than males engaged in nonfatal suicidal behaviors. Compared to Australia, Italy, New Zealand, the Philippines, and Hong Kong SAR, in the Pacific Islands suicide most often occurs in younger age groups. Results indicate notable variations between countries in choice of method. A greater proportion of suicides occurred by hanging in Pacific Islands, while inhalation of carbon monoxide, use of firearms, ingestion of chemicals and poisons, and drug overdose were the most frequent methods of choice in other areas. Conclusion: The information drawn from this study demonstrates the enormous variation in suicidal behavior across the areas involved in the START Study. Further research is needed to assess the reliability of the established data-recording systems for suicidal behaviors. The baseline data established in START may allow the development of suicide prevention initiatives sensitive to variation in the profile of suicide across different locations. © 2013 Hogrefe Publishing.

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Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

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Pós-graduação em Agronomia (Irrigação e Drenagem) - FCA

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Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

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Pós-graduação em Ciência da Computação - IBILCE

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O atual modelo do setor elétrico brasileiro permite igualdade de condições a todos os agentes e reduz o papel do Estado no setor. Esse modelo obriga as empresas do setor a melhorarem cada vez mais a qualidade de seu produto e, como requisito para este objetivo, devem fazer uso mais efetivo da enorme quantidade de dados operacionais que são armazenados em bancos de dados, provenientes da operação dos seus sistemas elétricos e que tem nas Usinas Hidrelétricas (UHE) a sua principal fonte de geração de energia. Uma das principais ferramentas para gerenciamento dessas usinas são os sistemas de Supervisão, Controle e Aquisição de Dados (Supervisory Control And Data Acquisition - SCADA). Assim, a imensa quantidade de dados acumulados nos bancos de dados pelos sistemas SCADA, muito provavelmente contendo informações relevantes, deve ser tratada para descobrir relações e padrões e assim ajudar na compreensão de muitos aspectos operacionais importantes e avaliar o desempenho dos sistemas elétricos de potência. O processo de Descoberta de Conhecimento em Banco de Dados (Knowledge Discovery in Database - KDD) é o processo de identificar, em grandes conjuntos de dados, padrões que sejam válidos, novos, úteis e compreensíveis, para melhorar o entendimento de um problema ou um procedimento de tomada de decisão. A Mineração de Dados (ou Data Mining) é o passo dentro do KDD que permite extrair informações úteis em grandes bases de dados. Neste cenário, o presente trabalho se propõe a realizar experimentos de mineração de dados nos dados gerados por sistemas SCADA em UHE, a fim de produzir informações relevantes para auxiliar no planejamento, operação, manutenção e segurança das hidrelétricas e na implantação da cultura da mineração de dados aplicada a estas usinas.

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Pós-graduação em Engenharia de Produção - FEB

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Pós-graduação em Ciência da Informação - FFC

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Current commercial and academic OLAP tools do not process XML data that contains XLink. Aiming at overcoming this issue, this paper proposes an analytical system composed by LMDQL, an analytical query language. Also, the XLDM metamodel is given to model cubes of XML documents with XLink and to deal with syntactic, semantic and structural heterogeneities commonly found in XML documents. As current W3C query languages for navigating in XML documents do not support XLink, XLPath is discussed in this article to provide features for the LMDQL query processing. A prototype system enabling the analytical processing of XML documents that use XLink is also detailed. This prototype includes a driver, named sql2xquery, which performs the mapping of SQL queries into XQuery. To validate the proposed system, a case study and its performance evaluation are presented to analyze the impact of analytical processing over XML/XLink documents.

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Background: Ontologies have increasingly been used in the biomedical domain, which has prompted the emergence of different initiatives to facilitate their development and integration. The Open Biological and Biomedical Ontologies (OBO) Foundry consortium provides a repository of life-science ontologies, which are developed according to a set of shared principles. This consortium has developed an ontology called OBO Relation Ontology aiming at standardizing the different types of biological entity classes and associated relationships. Since ontologies are primarily intended to be used by humans, the use of graphical notations for ontology development facilitates the capture, comprehension and communication of knowledge between its users. However, OBO Foundry ontologies are captured and represented basically using text-based notations. The Unified Modeling Language (UML) provides a standard and widely-used graphical notation for modeling computer systems. UML provides a well-defined set of modeling elements, which can be extended using a built-in extension mechanism named Profile. Thus, this work aims at developing a UML profile for the OBO Relation Ontology to provide a domain-specific set of modeling elements that can be used to create standard UML-based ontologies in the biomedical domain. Results: We have studied the OBO Relation Ontology, the UML metamodel and the UML profiling mechanism. Based on these studies, we have proposed an extension to the UML metamodel in conformance with the OBO Relation Ontology and we have defined a profile that implements the extended metamodel. Finally, we have applied the proposed UML profile in the development of a number of fragments from different ontologies. Particularly, we have considered the Gene Ontology (GO), the PRotein Ontology (PRO) and the Xenopus Anatomy and Development Ontology (XAO). Conclusions: The use of an established and well-known graphical language in the development of biomedical ontologies provides a more intuitive form of capturing and representing knowledge than using only text-based notations. The use of the profile requires the domain expert to reason about the underlying semantics of the concepts and relationships being modeled, which helps preventing the introduction of inconsistencies in an ontology under development and facilitates the identification and correction of errors in an already defined ontology.