427 research outputs found

    A METHODOLOGY FOR ONTOLOGICAL KNOWLEDGE CAPTURE FROM DATABASES \ud

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    The successful emergence of the Information and Communication Technologies (ICT) has contributed to the efficiency improvement in a number of economic sectors. However, some strategic economic sectors, such as construction, have not been targeted enough yet. Construction-related ICT solutions lack mechanisms to permit the effective integration of the whole supply chain. Semantic Web can tackle these issues. This paper presents a methodology for acquiring knowledge from construction-related databases. A domain ontology has been developed that contains the relevant concepts regarding supply management in the construction domain. The methodology basically consists of mapping the database content onto the ontology and a further this one’s population by applying a set of mapping rules.\ud Успешное появление информационно-коммуникационных технологий (ИКТ) внесло свой вклад в повышение эффективности многих секторов экономики. Однако, некоторые стратегические экономические сектора, такие, как строительство, не были все же достаточно исследованы. Связанные со строительством решения ИКТ испытывают недостаток в механизмах, позволяющих разрешать проблемы эффективной интеграции полной цепочки поставки. Семантическая Сеть может заняться этими проблемами. Эта статья представляет методологию, позволяющую извлекать знание из баз данных, связанных со строительством . Была разработана онтология домена, содержащая релевантные понятия, касающиеся управления поставками в домене строительства. Методология в основном состоит из отображения содержания базы данных на онтологию и дальнейшего ее заполнения , применяя набор правил отображения .\u

    A methodology for ontological knowledge capture from databases

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    The successful emergence of the Information and Communication Technologies (ICT) has contributed to the efficiency improvement in a number of economic sectors. However, some strategic economic sectors, such as construction, have not been targeted enough yet. Construction-related ICT solutions lack mechanisms to permit the effective integration of the whole supply chain. Semantic Web can tackle these issues. This paper presents a methodology for acquiring knowledge from construction-related databases. A domain ontology has been developed that contains the relevant concepts regarding supply management in the construction domain. The methodology basically consists of mapping the database content onto the ontology and a further this one’s population by applying a set of mapping rules.Успешное появление информационно-коммуникационных технологий (ИКТ) внесло свой вклад в повышение эффективности многих секторов экономики. Однако, некоторые стратегические экономические сектора, такие, как строительство, не были все же достаточно исследованы. Связанные со строительством решения ИКТ испытывают недостаток в механизмах, позволяющих разрешать проблемы эффективной интеграции полной цепочки поставки. Семантическая Сеть может заняться этими проблемами. Эта статья представляет методологию, позволяющую извлекать знание из баз данных, связанных со строительством . Была разработана онтология домена, содержащая релевантные понятия, касающиеся управления поставками в домене строительства. Методология в основном состоит из отображения содержания базы данных на онтологию и дальнейшего ее заполнения , применяя набор правил отображения

    Off-limb (spicule) DEM distribution from SoHO/SUMER observations

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    In the present work we derive a Differential Emission Measure (DEM) dis- tribution from a region dominated by spicules. We use spectral data from the Solar Ultraviolet Measurements of Emitted Radiation (SUMER) spectrometer on-board the Solar Heliospheric Observatory (SoHO) covering the entire SUMER wavelength range taken off-limb in the Northern polar coronal hole to construct this DEM distribution using the CHIANTI atomic database. This distribution is then used to study the thermal properties of the emission contributing to the 171 {\AA} channel in the Atmospheric Imaging Assembly (AIA) on-board the Solar Dynamics Observatory (SDO). From our off-limb DEM we found that the radiance in the AIA 171 {\AA} channel is dominated by emission from the Fe ix 171.07 {\AA} line and has sparingly little contribution from other lines. The product of the Fe ix 171.07 {\AA} line contribution function with the off-limb DEM was found to have a maximum at logTmax (K) = 5.8 indicating that during spicule observations the emission in this line comes from plasma at transition region temperatures rather than coronal. For comparison, the same product with a quiet Sun and prominence DEM were found to have a maximum at logT max (K) = 5.9 and logTmax (K) = 5.7, respectively. We point out that the interpretation of data obtained from the AIA 171 {\AA} filter should be done with foreknowledge of the thermal nature of the observed phenomenon. For example, with an off-limb DEM we find that only 3.6% of the plasma is above a million degrees, whereas using a quiet Sun DEM, this contribution rises to 15%.Comment: 12 pages, 6 figures accepted by Solar Physic

    Caracterización preliminar de emisiones de gases de efecto invernadero (CH4 y CO2) procedentes de volcanes de fango del Golfo de Cádiz

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    Mud volcanism represents an important migration pathway for methane and other gases from deeper reservoirs to the surface; however most submarine sources remain poor quantified. During SUBVENT2 cruise, water column over several mud volcanoes were surveyed for gas seepage characterization. Water samples of ROV Niskin and Rosette-CTD Niskin bottles were recovered above the Bonjardim, El Cid, Las Negras, Mercator, Algacel, Mvseis, Madrid and Yuma mud volcanoes, and at three newly discovered, mud volcano like structures, to quantify overall gases release fluxes from seabed. CO2 and CH4 concentrations were measured by potentiometric titration and using a gas chromatograph, respectively, in order to understand the relationship between physicochemical and geological processes. Gases concentrations decreased from shallower to deeper mud volcanoes. Values varied widely within 50 to 200 nM for CH4 and between 400 to 1500 μatm for fCO2. Greenhouse gases variations were large influenced by water column depth, temperature, salinity and possibly by anaerobic oxidation of methane (AOM). Our observations suggest that the emission of methane and carbon dioxide from the mud volcanoes structures studied here may be relevant at the present as a part of the carbon global cycle.Versión del edito

    Evaluation of turbulent dissipation rate retrievals from Doppler Cloud Radar

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    Turbulent dissipation rate retrievals from cloud radar Doppler velocity measurements are evaluated using independent, in situ observations in Arctic stratocumulus clouds. In situ validation data sets of dissipation rate are derived using sonic anemometer measurements from a tethered balloon and high frequency pressure variation observations from a research aircraft, both flown in proximity to stationary, ground-based radars. Modest biases are found among the data sets in particularly low- or high-turbulence regimes, but in general the radar-retrieved values correspond well with the in situ measurements. Root mean square differences are typically a factor of 4-6 relative to any given magnitude of dissipation rate. These differences are no larger than those found when comparing dissipation rates computed from tetheredballoon and meteorological tower-mounted sonic anemometer measurements made at spatial distances of a few hundred meters. Temporal lag analyses suggest that approximately half of the observed differences are due to spatial sampling considerations, such that the anticipated radar-based retrieval uncertainty is on the order of a factor of 2-3. Moreover, radar retrievals are clearly able to capture the vertical dissipation rate structure observed by the in situ sensors, while offering substantially more information on the time variability of turbulence profiles. Together these evaluations indicate that radar-based retrievals can, at a minimum, be used to determine the vertical structure of turbulence in Arctic stratocumulus clouds

    Computer simulation study of the nematic–vapour interface in the Gay–Berne model

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    We present computer simulations of the vapour–nematic interface of the Gay–Berne model. We considered situations which correspond to either prolate or oblate molecules. We determine the anchoring of the nematic phase and correlate it with the intermolecular potential parameters. On the other hand, we evaluate the surface tension associated to this interface. We find a corresponding states law for the surface tension dependence on the temperature, valid for both prolate and oblate molecules.Fundación Portuguesa para la Ciencia y la Tecnología EXCL / FIS-NAN / 0083/2012Ministerio de Economía y Competitividad FIS2012-32455Junta de Andalucía P09-FQM-493

    Seafloor deformation related to Quaternary tectonics in the Majorca Channel, Balearic Promontory (Western Mediterranean)

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    El análisis morfotectónico del sector central del Promontorio Balear, entre las islas de Ibiza y Mallorca, mediante batimetría multihaz y perfiles sísmicos de muy alta resolución ha permitido diferenciar varios rasgos morfológicos relacionados con la tectónica a dos escalas. Los elementos de gran escala, de dirección NE-SO, son: i) el escarpe Émile Baudot; ii) el monte submarino Émile Baudot, y iii) la alineación de montes submarinos Ausiàs March y Ses Olives. Los elementos de pequeña escala son: i) dos elevaciones longitudinales (ENE-OSO); ii) escarpes rectilíneos (NO-SE a NE-SO); iii) depresiones tectónicas (NNE SSO a NE-SO); y iv) alineaciones rectilíneas de pockmarks (NO-SE a NNE-SSO). Los elementos de mayor tamaño responden a la configuración estructural neógeno-cuaternaria. El escarpe Émile Baudot limita el Promontorio Balear y la cuenca oceánica del Mediterráneo Occidental. La alineación de montes submarinos Ausiàs March y Ses Olives está generada por una fase extensional, y el monte submarino Émile Baudot forma parte de una alineación volcánica NO-SE asociada a la Zona de Fractura de Ibiza. Los elementos de pequeña escala están relacionados con estructuras tectónicas activas que deforman las unidades sedimentarias del Cuaternario y el fondo marino. Las elevaciones longitudinales están generadas por pliegues anticlinales, mientras que el resto de estructuras están asociadas a la actividad de fallas normales de buzamiento alto.A morphotectonic analysis has been carried out between the islands of Ibiza and Majorca in the central sector of the Balearic Promontory using multibeam bathymetry and very high-resolution seismic profiles. Several morphological features related to tectonics at two different scales have been differentiated. The large-scale features have a NE-SW direction, they are: i) the Émile Baudot Escarpment; ii) the Émile Baudot seamount, and iii) the Ausiàs March and Ses Olives seamounts alignment. The differentiated small-scale elements are i) two longitudinal elevations (ENE-WSW); ii) rectilinear scarps (NW-SE to NE-SW); iii) tectonic depressions limited by one or two scarps (NNE-SSW to NE-SW), and iv) rectilinear pockmarks alignments (NW-SE to NNE-SSW). The largest elements respond to the Neogene-Quaternary structural configuration. The Émile Baudot escarpment is the limit between the Balearic Promontory and the Western Mediterranean oceanic basin. The alignment of the Ausiàs March and Ses Olives seamounts respond to the last extensional phase, and the Émile Baudot seamount forms part of a NW-SE volcanic alignment that could be associated with the Ibiza Fracture Zone. The smaller elements are related to active tectonic structures that deform Quaternary sedimentary units and the seafloor. The longitudinal elevations correspond to anticlinal folds, while the rest of the structures are associated to the activity of near vertical normal faults.En prens
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