53 research outputs found

    Business intelligence no suporte a decisões sobre comunicações: descrição de um caso.

    Get PDF
    O projecto descrito tem o objectivo de apoiar decisões de investimento em infraestruturas de comunicação na Electricidade Dos Açores (EDA), a empresa responsável pela geração, transporte e venda de corrente eléctrica na Região Autónoma dos Açores. A decisão imediata a apoiar consistia em saber se as comunicações entre ilhas deveriam passar para tecnologias Voice over IP (VoIP), um serviço actualmente contratado em regime de outsourcing. Foi estabelecido um projecto de business intelligence, usando tecnologias OLAP do Microsoft SQL Server, para ler e pré-processar os ficheiros CSV de grande dimensão, combinar esses dados com bases de dados existentes e apresentar os resultados sobre a forma de cubos multidimensionais. Posteriormente, implementaram-se igualmente algoritmos de data mining, integrando na metodologia CRISP-DM as duas técnicas utilizadas. Construindo vários modelos foi possível, além de apoiar a decisão pretendida, identificar situações ineficientes e mesmo fraudulentas. Os modelos construídos foram ainda disponibilizados aos decisores estratégicos e de controlo, assim como toda a estrutura de reutilização, manutenção e realimentação que suporta o OLAP e os modelos de data mining.ABSTRACT: This project addresses decisions of investment on communication infrastructures in Electricidade dos Açores (EDA), the local Electric Company in the Azores Islands. The main decision was that EDA communications should be moving to Voice over IP (VoIP) from present telephone lines, outsourced to an external communications company. At the beginning, a business intelligence project was set, with the objective of getting data from the communications company and analyzing it in order to offer useful information to decision makers. The system uses Microsoft SQL server technologies to establish an OnLine Analytical Processing (OLAP) application. It translates big CSV flat files in a ROLAP infrastructure and presents the results as multidimensional data cubes. Latter some data mining models were implemented and both techniques were incorporated in the CRISP-DM process model. Different models identified several inefficient procedures and even fraud situations as long as supporting the investment decision. These models as long as all the technology developed for gathering data, maintain an manage the OLAP cubes and data mining models were made available to control and strategic decision makers

    Suporte à Decisão em Tecnologias de Comunicação : um caso com utilização de metodologias OLAP e Data Mining

    Get PDF
    Este artigo descreve um Sistema de Apoio à Decisão capaz de fornecer informação precisa e de qualidade sobre as comunicações na Electricidade Dos Açores (EDA). A decisão imediata a apoiar consistia em saber se as comunicações entre ilhas deveriam passar para tecnologias Voice over IP (VoIP), um serviço actualmente contratado a uma empresa de comunicações externa. Num projecto de business intelligence e usando tecnologias Microsoft SQL Server, o sistema lê e pré-processa ficheiros CSV de grande dimensão, recebidas da empresa de comunicações, combina esses dados com bases de dados existentes e apresenta os resultados sobre a forma de cubos multidimensionais. Posteriormente, este trabalho foi integrado num projecto de data minig, usando a metodologia CRISP-DM, tendo sido possível além de apoiar a decisão pretendida identificar situações ineficientes e mesmo de utilização fraudulenta de equipamentos de comunicação. Vários modelos foram construídos e disponibilizados a diferentes decisores para apoiar decisões estratégicas e de controlo.info:eu-repo/semantics/publishedVersio

    Suporte à decisão em tecnologias de comunicação: utilização de OLAP e data mining.

    Get PDF
    3ª Conferência Ibérica de Sistemas e Tecnologias de Informação (CISTI 2008), 19 a 21 de Junho de 2008, organizada pela Universidad de Vigo.Este artigo descreve um Sistema de Apoio à Decisão capaz de fornecer informação precisa e de qualidade sobre as comunicações na Electricidade Dos Açores (EDA). A decisão imediata a apoiar consistia em saber se as comunicações entre ilhas deveriam passar para tecnologias Voice over IP (VoIP), um serviço actualmente contratado a uma empresa de comunicações externa. Num projecto de business intelligence e usando tecnologias Microsoft SQL server, o sistema lê e pré-processa ficheiros CSV de grande dimensão, recebidas da empresa de comunicações, combina esses dados com bases de dados existentes e apresenta os resultados sobre a forma de cubos multidimensionais. Posteriormente, este trabalho foi integrado num projecto de data minig, usando a metodologia CRISP-DM, tendo sido possível além de apoiar a decisão pretendida identificar situações ineficientes e mesmo de utilização fraudulenta de equipamentos de comunicação. Vários modelos foram construídos e disponibilizados a diferentes decisores para apoiar decisões estratégicas e de controlo

    Deep weathering in the semi-arid Coastal Cordillera, Chile

    Get PDF
    The weathering front is the boundary beneath Earth’s surface where pristine rock is converted into weathered rock. It is the base of the “critical zone”, in which the lithosphere, biosphere, and atmosphere interact. Typically, this front is located no more than 20 m deep in granitoid rock in humid climate zones. Its depth and the degree of rock weathering are commonly linked to oxygen transport and fluid flow. By drilling into fractured igneous rock in the semi-arid climate zone of the Coastal Cordillera in Chile we found multiple weathering fronts of which the deepest is 76 m beneath the surface. Rock is weathered to varying degrees, contains core stones, and strongly altered zones featuring intensive iron oxidation and high porosity. Geophysical borehole measurements and chemical weathering indicators reveal more intense weathering where fracturing is extensive, and porosity is higher than in bedrock. Only the top 10 m feature a continuous weathering gradient towards the surface. We suggest that tectonic preconditioning by fracturing provided transport pathways for oxygen to greater depths, inducing porosity by oxidation. Porosity was preserved throughout the weathering process, as secondary minerals were barely formed due to the low fluid flow

    Stationary solutions for the parity-even sector of the CPT-even and Lorentz-covariance-violating term of the standard model extension

    Full text link
    In this work, we focus on some properties of the parity-even sector of the CPT-even electrodynamics of the standard model extension. We analyze how the six non-birefringent terms belonging to this sector modify the static and stationary classical solutions of the usual Maxwell theory. We observe that the parity-even terms do not couple the electric and magnetic sectors (at least in the stationary regime). The Green's method is used to obtain solutions for the field strengths E and B at first order in the Lorentz- covariance-violating parameters. Explicit solutions are attained for point-like and spatially extended sources, for which a dipolar expansion is achieved. Finally, it is presented an Earth-based experiment that can lead (in principle) to an upper bound on the anisotropic coefficients as stringent as (κ~e)ij<2.9×1020.(\widetilde{\kappa}_{e-}) ^{ij}<2.9\times10^{-20}.Comment: 8 pages, revtex style, revised published version, to appear in EPJC (2009

    Global assessment of marine plastic exposure risk for oceanic birds

    Get PDF
    Plastic pollution is distributed patchily around the world’s oceans. Likewise, marine organisms that are vulnerable to plastic ingestion or entanglement have uneven distributions. Understanding where wildlife encounters plastic is crucial for targeting research and mitigation. Oceanic seabirds, particularly petrels, frequently ingest plastic, are highly threatened, and cover vast distances during foraging and migration. However, the spatial overlap between petrels and plastics is poorly understood. Here we combine marine plastic density estimates with individual movement data for 7137 birds of 77 petrel species to estimate relative exposure risk. We identify high exposure risk areas in the Mediterranean and Black seas, and the northeast Pacific, northwest Pacific, South Atlantic and southwest Indian oceans. Plastic exposure risk varies greatly among species and populations, and between breeding and nonbreeding seasons. Exposure risk is disproportionately high for Threatened species. Outside the Mediterranean and Black seas, exposure risk is highest in the high seas and Exclusive Economic Zones (EEZs) of the USA, Japan, and the UK. Birds generally had higher plastic exposure risk outside the EEZ of the country where they breed. We identify conservation and research priorities, and highlight that international collaboration is key to addressing the impacts of marine plastic on wide-ranging speciespublishedVersio

    Global assessment of marine plastic exposure risk for oceanic birds

    Get PDF
    Plastic pollution is distributed patchily around the world’s oceans. Likewise, marine organisms that are vulnerable to plastic ingestion or entanglement have uneven distributions. Understanding where wildlife encounters plastic is crucial for targeting research and mitigation. Oceanic seabirds, particularly petrels, frequently ingest plastic, are highly threatened, and cover vast distances during foraging and migration. However, the spatial overlap between petrels and plastics is poorly understood. Here we combine marine plastic density estimates with individual movement data for 7137 birds of 77 petrel species to estimate relative exposure risk. We identify high exposure risk areas in the Mediterranean and Black seas, and the northeast Pacific, northwest Pacific, South Atlantic and southwest Indian oceans. Plastic exposure risk varies greatly among species and populations, and between breeding and non-breeding seasons. Exposure risk is disproportionately high for Threatened species. Outside the Mediterranean and Black seas, exposure risk is highest in the high seas and Exclusive Economic Zones (EEZs) of the USA, Japan, and the UK. Birds generally had higher plastic exposure risk outside the EEZ of the country where they breed. We identify conservation and research priorities, and highlight that international collaboration is key to addressing the impacts of marine plastic on wide-ranging species

    Comparative genomics reveals insights into avian genome evolution and adaptation

    Get PDF
    Birds are the most species-rich class of tetrapod vertebrates and have wide relevance across many research fields. We explored bird macroevolution using full genomes from 48 avian species representing all major extant clades. The avian genome is principally characterized by its constrained size, which predominantly arose because of lineage-specific erosion of repetitive elements, large segmental deletions, and gene loss. Avian genomes furthermore show a remarkably high degree of evolutionary stasis at the levels of nucleotide sequence, gene synteny, and chromosomal structure. Despite this pattern of conservation, we detected many non-neutral evolutionary changes in protein-coding genes and noncoding regions. These analyses reveal that pan-avian genomic diversity covaries with adaptations to different lifestyles and convergent evolution of traits

    The Eighteenth Data Release of the Sloan Digital Sky Surveys: Targeting and First Spectra from SDSS-V

    Full text link
    The eighteenth data release of the Sloan Digital Sky Surveys (SDSS) is the first one for SDSS-V, the fifth generation of the survey. SDSS-V comprises three primary scientific programs, or "Mappers": Milky Way Mapper (MWM), Black Hole Mapper (BHM), and Local Volume Mapper (LVM). This data release contains extensive targeting information for the two multi-object spectroscopy programs (MWM and BHM), including input catalogs and selection functions for their numerous scientific objectives. We describe the production of the targeting databases and their calibration- and scientifically-focused components. DR18 also includes ~25,000 new SDSS spectra and supplemental information for X-ray sources identified by eROSITA in its eFEDS field. We present updates to some of the SDSS software pipelines and preview changes anticipated for DR19. We also describe three value-added catalogs (VACs) based on SDSS-IV data that have been published since DR17, and one VAC based on the SDSS-V data in the eFEDS field.Comment: Accepted to ApJ

    The eighteenth data release of the Sloan Digital Sky Surveys : targeting and first spectra from SDSS-V

    Get PDF
    The eighteenth data release of the Sloan Digital Sky Surveys (SDSS) is the first one for SDSS-V, the fifth generation of the survey. SDSS-V comprises three primary scientific programs, or "Mappers": Milky Way Mapper (MWM), Black Hole Mapper (BHM), and Local Volume Mapper (LVM). This data release contains extensive targeting information for the two multi-object spectroscopy programs (MWM and BHM), including input catalogs and selection functions for their numerous scientific objectives. We describe the production of the targeting databases and their calibration- and scientifically-focused components. DR18 also includes ~25,000 new SDSS spectra and supplemental information for X-ray sources identified by eROSITA in its eFEDS field. We present updates to some of the SDSS software pipelines and preview changes anticipated for DR19. We also describe three value-added catalogs (VACs) based on SDSS-IV data that have been published since DR17, and one VAC based on the SDSS-V data in the eFEDS field.Publisher PDFPeer reviewe
    corecore