1,724,502 research outputs found
System architecture induces document architecture
No full textThe documentation of an architecture is as important as the architecture itself. Tasked with communicating the structure and behaviour of a system and its constituent components to various stakeholders, the documentation is not trivial to produce. It becomes even harder in open, modular systems where components can be replaced and reused in each progressive build. How should documentation for such systems be produced and how can it be made to easily evolve along with the system it describes? We propose that there is a close mapping between the system architecture and its documentation. We describe a relational model for the architecture of open systems, paying close attention to the property that certain components can be reused or replaced. We then use ideas from storytelling and a discourse theory called Rhetorical Structure Theory (RST) to propose a narrative-based approach to architecture documentation; giving both a generic narrative template for component descriptions and a RST-based relational model for the document architecture. We show how the two models (system and documentation) map onto each other and use this mapping to demonstrate how document fragments can be stored, automatically extracted and collated to closely reflect the system’s architecture
Multiple Emission Regions in Jets of the Low-Luminosity Active Galactic Nucleus in NGC 4278
Get PDFThe Large High Altitude Air Shower Observatory (LHAASO) has detected very-high-energy gamma rays from the low-ionization nuclear emission-line region galaxy NGC 4278, which has a low-luminosity active galactic nucleus (LLAGN) and symmetric, mildly relativistic S-shaped twin jets detected by radio observations. Few LLAGNs have been detected in gamma rays due to their faintness. Earlier, several radio-emitting components were detected in the jets of NGC 4278. We model their radio emission with synchrotron emission of ultra-relativistic electrons to estimate the strength of the magnetic field inside these components within a time-dependent framework after including the ages of the different components. We show that the synchrotron and synchrotron self-Compton emission by these components cannot explain the Swift X-ray data and the LHAASO gamma-ray data from NGC 4278. We suggest that a separate component in one of the jets is responsible for the high-energy emission, whose age, size, magnetic field, and the spectrum of the ultra-relativistic electrons inside it have been estimated after fitting the multiwavelength data of NGC 4278 with the sum of the spectral energy distributions from the radio components and the high-energy component. We note that the radio components of NGC 4278 are larger than the high-energy component, which has also been observed in several high-luminosity active galactic nuclei
Historia verdadera de la enfermedad del ... señor Marqs. Vanmarke, Capitan General de este Reyno, &c. y demostracion de los errores, y equivocaciones de otra, que dió al Público el Dr. D. Narciso Peyri [Texto impreso]
Get PDFHay un ejemplar encuadernado con: Discursos gratulatorios que en las visitas publicas... practicadas por la... ciudad de Valencia, cerca de... Don Iosef Climent... i Fr. Don Rafael Lasala... (XVIII/4278).Sign. : [ ]4, B-G4Reclamo
Linked collectors and determiners for: Ustilaginales externi.
No full textNatural history specimen data linked to collectors and determiners held within, "Ustilaginales externi". Claims or attributions were made on Bionomia by volunteer Scribes, <a href="http://bionomia.net/dataset/bcacc0f2-c7ab-4278-85c2-720e57da676c">https://bionomia.net/dataset/bcacc0f2-c7ab-4278-85c2-720e57da676c</a> using specimen data from the dataset aggregated by the Global Biodiversity Information Facility, <a href="https://gbif.org/dataset/bcacc0f2-c7ab-4278-85c2-720e57da676c">https://gbif.org/dataset/bcacc0f2-c7ab-4278-85c2-720e57da676c</a>. Formatted as a Frictionless Data package
Linked collectors and determiners for: Geneva Herbarium – General Collection (G).
No full textNatural history specimen data linked to collectors and determiners held within, "Geneva Herbarium – General Collection (G)". Claims or attributions were made on Bionomia by volunteer Scribes, <a href="http://bionomia.net/dataset/f577c9f3-ae71-4278-b6bf-512ba1dfaa21">https://bionomia.net/dataset/f577c9f3-ae71-4278-b6bf-512ba1dfaa21</a> using specimen data from the dataset aggregated by the Global Biodiversity Information Facility, <a href="https://gbif.org/dataset/f577c9f3-ae71-4278-b6bf-512ba1dfaa21">https://gbif.org/dataset/f577c9f3-ae71-4278-b6bf-512ba1dfaa21</a>. Formatted as a Frictionless Data package
Linked collectors and determiners for: Taxonomic Revision of the Ant-Acacias (Fabaceae, Mimosoideae, Acacia, Series Gummiferae) of the New World.
No full textNatural history specimen data linked to collectors and determiners held within, "Taxonomic Revision of the Ant-Acacias (Fabaceae, Mimosoideae, Acacia, Series Gummiferae) of the New World". Claims or attributions were made on Bionomia by volunteer Scribes, <a href="http://bionomia.net/dataset/a839d8c3-a899-4278-86d2-667a5768008d">https://bionomia.net/dataset/a839d8c3-a899-4278-86d2-667a5768008d</a> using specimen data from the dataset aggregated by the Global Biodiversity Information Facility, <a href="https://gbif.org/dataset/a839d8c3-a899-4278-86d2-667a5768008d">https://gbif.org/dataset/a839d8c3-a899-4278-86d2-667a5768008d</a>. Formatted as a Frictionless Data package
Fermi-LAT Detection of the Low-luminosity Radio Galaxy NGC 4278 during the LHAASO Campaign
No full textWe present a study of the high-energy properties of the compact symmetric object NGC 4278, recently associated with a TeV source by the Large High Altitude Air Shower Observatory (LHAASO) collaboration. We conducted a dedicated analysis of a Fermi Large Area Telescope (LAT) region around NGC 4278, limited to the LHAASO campaign conducted from 2021 March to 2022 October. A statistically significant emission (∼4.3σ) was revealed, spatially consistent with the radio position of NGC 4278 and the LHAASO source. The Fermi-LAT source is detected above 8 GeV, exhibiting a hard spectrum (photon index Γ = 1.3 ± 0.3) and a γ-ray luminosity of L ≃ 4 × 10 erg s. A serendipitous Swift X-Ray Telescope (XRT) observation of NGC 4278 during the TeV campaign reveals the source in a high state, with a flux F0.5−8keV=5−2+3×10−12ergs−1cm−2, compatible with the highest luminosity level observed in previous Chandra pointings. The high-energy spectral energy distribution of the source and the intense flux variation observed in the X-ray band support a jet origin for the observed radiation. We suggest that the significant enhancement of the high-energy flux observed during the LHAASO campaign is due to a transient, highly energetic perturbation in the jet. The detection of NGC 4278 at both high and very high energies opens new frontiers in studying particle acceleration processes. It reveals that even compact, low-power radio galaxies can exceed the sensitivity thresholds of GeV and TeV instruments, becoming promising targets for the upcoming Cherenkov Telescope Array Observatory
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