633 research outputs found
Sistema de predição de alarmes em processos industriais por classificação não-supervisionada
In this work an alarm prediction system is proposed. Its main aims are to contribute to the establishment of predictive industrial maintenance guidelines and to produce a management decision support tool. The proposed system obtains readings from many sensors that are installed in the industrial plant, extract its characteristics and evaluates the equipment’s health. The diagnosis and prognosis implies in a
classification of the industrial plant’s operational condition. Classification and regression trees are applied in this paper. A measurement sample from 73 sensors installed in a hydroelectric power plant is utilized to test and validate the proposed methodology. The measurements were obtained in a 15 months period.Um sistema de predição de alarmes com a finalidade de auxiliar a implantação de uma política de manutenção preditiva industrial e de constituir-se em uma ferramenta gerencial de apoio à tomada de decisão é proposto neste trabalho. O sistema adquire leituras de diversos sensores instalados na planta, extrai suas características e avalia a saúde do equipamento. O diagnóstico e prognóstico implica a classificação das condições de operação da planta. Técnicas de árvores de regressão e classificação não-supervisionada são utilizadas neste artigo. Uma amostra das medições de 73 variáveis feitas por sensores instalados em uma usina hidrelétrica foi utilizada para testar e validar a proposta. As medições foram amostradas em um período de 15 meses
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Rarity of monodominance in hyperdiverse Amazonian forests.
Tropical forests are known for their high diversity. Yet, forest patches do occur in the tropics where a single tree species is dominant. Such "monodominant" forests are known from all of the main tropical regions. For Amazonia, we sampled the occurrence of monodominance in a massive, basin-wide database of forest-inventory plots from the Amazon Tree Diversity Network (ATDN). Utilizing a simple defining metric of at least half of the trees ≥ 10 cm diameter belonging to one species, we found only a few occurrences of monodominance in Amazonia, and the phenomenon was not significantly linked to previously hypothesized life history traits such wood density, seed mass, ectomycorrhizal associations, or Rhizobium nodulation. In our analysis, coppicing (the formation of sprouts at the base of the tree or on roots) was the only trait significantly linked to monodominance. While at specific locales coppicing or ectomycorrhizal associations may confer a considerable advantage to a tree species and lead to its monodominance, very few species have these traits. Mining of the ATDN dataset suggests that monodominance is quite rare in Amazonia, and may be linked primarily to edaphic factors
Morphologic characterization of sweet potato accesses from the germplasm bank of the Universidade Federal dos Vales do Jequitinhonha e Mucuri, Brazil
O trabalho teve como objetivo caracterizar morfologicamente os acessos de batata-doce do banco de germoplasma da Universidade Federal dos Vales do Jequitinhonha e Mucuri (UFVJM). O experimento foi realizado no Setor de Olericultura da UFVJM, per?odo de fevereiro a novembro de 2006, utilizando-se o delineamento em blocos casualizados (DBC), contendo 65 tratamentos e 3 repeti??es, totalizando 195 parcelas de 4,5 m? cada. As avalia??es da parte vegetativa foram feitas tr?s meses ap?s o plantio e a colheita de ra?zes foi realizada nove meses ap?s o plantio das ramas. Observou-se pelo dendrograma de dissimilaridade morfol?gica, que os acessos da cole??o do banco de germoplasma da UFVJM apresentaram ampla variabilidade morfol?gica. Os descritores referentes ? parte a?rea se mostraram significativos com diferen?a entre clones, pelo teste Scott-Knott (p=0,05), diferentemente daqueles referentes ? raiz.Funda??o de Amparo ? Pesquisa do Estado de Minas Gerais (FAPEMIG)Empresa de Pesquisa Agropecu?ria de Minas Gerais (EPAMIG)Conselho Nacional de Desenvolvimento Cient?fico e Tecnol?gico (CNPq)Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior (CAPES)Sweet potato accesses from the germplasm bank of the Universidade Federal dos Vales do Jequitinhonha e Mucuri, Diamantina, Minas Gerais state, Brazil were characterized. The experiment was carried out between February and November 2006, using a randomized blocks design, with 65 treatments and three replications, totaling 195 plots. The evaluation of the vegetative part was carried out three months after planting and the roots were harvested nine months after planting. Based on the dendrogram of morphologic differences we observed a great morphologic variability on the accesses. The characteristics of the vegetative part showed significant differences among the clones, by Scott Knot test at 5% probability, differently from those of the roots
Descripción de cuatro especies nuevas del subgrupo Drosophila fasciola, gruporepleta (Diptera, Drosophilidae) en dos bosques nublados del Ecuador
The Ninth Data Release of the Sloan Digital Sky Survey: First Spectroscopic Data from the SDSS-III Baryon Oscillation Spectroscopic Survey
The Sloan Digital Sky Survey III (SDSS-III) presents the first spectroscopic
data from the Baryon Oscillation Spectroscopic Survey (BOSS). This ninth data
release (DR9) of the SDSS project includes 535,995 new galaxy spectra (median
z=0.52), 102,100 new quasar spectra (median z=2.32), and 90,897 new stellar
spectra, along with the data presented in previous data releases. These spectra
were obtained with the new BOSS spectrograph and were taken between 2009
December and 2011 July. In addition, the stellar parameters pipeline, which
determines radial velocities, surface temperatures, surface gravities, and
metallicities of stars, has been updated and refined with improvements in
temperature estimates for stars with T_eff<5000 K and in metallicity estimates
for stars with [Fe/H]>-0.5. DR9 includes new stellar parameters for all stars
presented in DR8, including stars from SDSS-I and II, as well as those observed
as part of the SDSS-III Sloan Extension for Galactic Understanding and
Exploration-2 (SEGUE-2).
The astrometry error introduced in the DR8 imaging catalogs has been
corrected in the DR9 data products. The next data release for SDSS-III will be
in Summer 2013, which will present the first data from the Apache Point
Observatory Galactic Evolution Experiment (APOGEE) along with another year of
data from BOSS, followed by the final SDSS-III data release in December 2014.Comment: 9 figures; 2 tables. Submitted to ApJS. DR9 is available at
http://www.sdss3.org/dr
Ituglanis agreste, a new catfish from the rio de Contas basin, northeastern Brazil (Siluriformes: Trichomycteridae)
The global EPTO database: Worldwide occurrences of aquatic insects
Motivation: Aquatic insects comprise 64% of freshwater animal diversity and are widely used as bioindicators to assess water quality impairment and freshwater ecosystem health, as well as to test ecological hypotheses. Despite their importance, a comprehensive, global database of aquatic insect occurrences for mapping freshwater biodiversity in macroecological studies and applied freshwater research is missing. We aim to fill this gap and present the Global EPTO Database, which includes worldwide geo-referenced aquatic insect occurrence records for four major taxa groups: Ephemeroptera, Plecoptera, Trichoptera and Odonata (EPTO). Main type of variables contained: A total of 8,368,467 occurrence records globally, of which 8,319,689 (99%) are publicly available. The records are attributed to the corresponding drainage basin and sub-catchment based on the Hydrography90m dataset and are accompanied by the elevation value, the freshwater ecoregion and the protection status of their location. Spatial location and grain: The database covers the global extent, with 86% of the observation records having coordinates with at least four decimal digits (11.1 m precision at the equator) in the World Geodetic System 1984 (WGS84) coordinate reference system. Time period and grain: Sampling years span from 1951 to 2021. Ninety-nine percent of the records have information on the year of the observation, 95% on the year and month, while 94% have a complete date. In the case of seven sub-datasets, exact dates can be retrieved upon communication with the data contributors.Major taxa and level of measurement: Ephemeroptera, Plecoptera, Trichoptera and Odonata, standardized at the genus taxonomic level. We provide species names for 7,727,980 (93%) records without further taxonomic verification. Software format: The entire tab-separated value (.csv) database can be downloaded and visualized at https://glowa bio.org/proje ct/epto_datab ase/. Fifty individual datasets are also available at https://fred.igb-berlin. de, while six datasets have restricted access. For the latter, we share metadata and the contact details of the authors
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