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11.
Due to its intensive data processing and highly distributed organization, the multidisciplinary Earth Science applications community is uniquely positioned for the uptake and exploitation of Grid technologies. Currently Enabling Grids for E-sciencE, and other large Grid infrastructures are already deployed and capable of operational services. So far however, the adoption and exploitation of Grid technology throughout the Earth Science community has been slower than expected. The Dissemination and Exploitation of GRids in Earth sciencE project, proposed by the European Commission to assist and accelerate this process in a number of different ways, had between its main goals the creation of a roadmap towards Earth Science Grid platform. This paper presents the resulting roadmap.  相似文献   
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13.
The Jalovecký Creek catchment, Slovakia (area 22.2 km2, mean elevation 1500 m a.s.l.), is likely the last big valley complex in the Carpathian Mountains, in which the hydrological cycle is still governed by natural processes. Hydrological research is conducted there since the end of the 1980s. The overall mission of the research is to increase the knowledge about the hydrological cycle in the highest part of the Carpathians. The research agenda, briefly introduced in the first part of this article, is focused on water balance, snow accumulation and melt and runoff formation. Recent analysis of precipitation, discharge, snow cover and isotopic data from period 1989–2018 indicates that hydrological cycle has become more dynamic since 2014. Although several indicators suggest that it could be related to the cold part of the year, direct links with snow storage and the contribution of snowmelt water to catchment runoff were not confirmed. The second part of the article is therefore focused on an analysis of daily cycles in streamflow in March to June 1988–2018 to obtain a deeper insight into the snowmelt process. We describe characteristics of the cycles and examine their variability over the study period. The results indicate that less snow at the lowest elevations (800–1150 m a.s.l.) since 2009 could have influenced the cessation of the cycles in June since 2010. The possible role of the decreased amount of snow at the lowest elevations in changes in runoff characteristics is also suggested by an increase in time lags between maximum discharges during the events and maximum air temperatures preceding discharge maxima measured near the catchment outlet (at 750 m a.s.l.) in spring 2018 compared to springs with a similar number of streamflow cycles in the years 1988, 2000 and 2009. Wavelet analysis did not indicate changes in global power spectra in hourly discharge and air temperature data.  相似文献   
14.
The CP star HR 446 (HD 9531, B8p V,m=5.69) is one of the CP stars with no definitely assigned peculiarity type. In this contribution it is shown by application of the synthetic spectra, that the star is a helium-weak type of the titanium-strontium subgroup. Photometric observations confirmed the rotational period of 0.6684 d discovered earlier. Our photometric observations do not permit to find rapid variability exceeding 0.005 mag within the limits of 5–300 min.Paper presented at the 11th European Regional Astronomical meetings of the IAU on New Windows to the Universe, held 3–8 July, 1989, Tenerife, Canary Islands, Spain.  相似文献   
15.
Sixty-one blue spectrograms of TX UMa were obtained in the years 1969–1970, mainly in phases close to the primary minimum of the eclipsing system. The radial velocity curve displays clear rotational effect from which much higher than synchronous rotational velocity of the blue (B8V) component has been formally derived. However, this discrepancy is probably due to the presence of the tenous accretion disk around the primary. The disk is apparently fed by the intermittent mass transfer as indicated by the occasional changes of orbital period of the system. From all available radial velocity data an improved set of spectroscopic orbital elements is derived. The behaviour of the spectral lines in and out of the primary minimum is compared. Metallic lines of the cold (F7IV) secondary component are clearly seen exclusively in phases 0.988 to 0.012.Paper presented at the 11th European Regional Astronomical Meetings of the IAU on New Windows to the Universe, held 3–8 July, 1989, Tenerife, Canary Islands, Spain.  相似文献   
16.
Magnetic images of Chelyabinsk meteorite's (fragment F1 removed from Chebarkul lake) thin section have been unraveled by a magnetic scanning system from Youngwood Science and Engineering (YSE) capable of resolving magnetic anomalies down to 10?3 mT range from about 0.3 mm distance between the probe and meteorite surface (resolution about 0.15 mm). Anomalies were produced repeatedly, each time after application of magnetic field pulse of varying amplitude and constant, normal or reversed, direction. This process resulted in both magnetizing and demagnetizing of the meteorite thin section, while keeping the magnetization vector in the plane of the thin section. Analysis of the magnetic data allows determination of coercivity of remanence (Bcr) for the magnetic sources in situ. Value of Bcr is critical for calculating magnetic forces applicable during missions to asteroids where gravity is compromised. Bcr was estimated by two methods. First method measured varying dipole magnetic field strength produced by each anomaly in the direction of magnetic pulses. Second method measured deflections of the dipole direction from the direction of magnetic pulses. Bcr of magnetic sources in Chelyabinsk meteorite ranges between 4 and 7 mT. These magnetic sources enter their saturation states when applying 40 mT external magnetic field pulse.  相似文献   
17.
The Ljubija siderite deposits, hosted by a Carboniferous sedimentary complex within the Inner Dinarides, occur as stratabound replacement-type ore bodies in limestone blocks and as siderite–sulfides veins in shale. Three principal types of ore textures have been recognized including massive dark siderite and ankerite, siderite with zebra texture, and siderite veins. The ore and host rocks have been investigated by a combination of inorganic (major, trace, and rare earth element concentrations), organic (characterization of hydrocarbons including biomarkers), and stable isotope geochemical methods (isotope ratios of carbonates, sulfides, sulfates, kerogen, and individual hydrocarbons). New results indicate a marine origin of the host carbonates and a hydrothermal–metasomatic origin of the Fe mineralization. The differences in ore textures (e.g., massive siderite, zebra siderite) are attributed to physicochemical variations (e.g., changes in acidity, temperature, and/or salinity) of the mineralizing fluids and to the succession and intensity of replacement of host limestone. Vein siderite was formed by precipitation from hydrothermal fluids in the late stage of mineralization. The equilibrium fractionation of stable isotopes reveals higher formation temperatures for zebra siderites (around 245°C) then for siderite vein (around 185°C). Sulfur isotope ratios suggest Permian seawater or Permian evaporites as the main sulfur source. Fluid inclusion composition confirms a contribution of the Permian seawater to the mineralizing fluids and accord with a Permian mineralization age. Organic geochemistry data reflect mixing of hydrocarbons at the ore site and support the hydrothermal–metasomatic origin of the Ljubija iron deposits.  相似文献   
18.
Summary The possibilities of improving of the construction of trajectories of air particles polluted by antropogeneous admixtures are discussed. With this in view attention is devoted to the ordered vertical velocities of dynamic origin and a simple method of approximate construction of the trajectories in the boundary layer of the atmosphere, where the flow is markedly affected by the Earth's surface, is discussed.  相似文献   
19.
Moravany-Lopata, located in the complex of sites in the middle Vah basin, dates to the period immediately preceding the LGM. The authors use this site to demonstrate the usefulness of mineralogical, sedimentological, palaeomalacological, and anthropogenic criteria for the correlation of loess profiles. This analysis is especially concerned with sites in loess territories where the loess layers covering archaeological levels are not thick. Such sites occur frequently on the plateaus of the northern part of Central Europe, though they appear most notably in the areas in which the last loess cover, corresponding to the period after the last Pleniglacial and/or Late Glacial postloess sediments, is absent. The archaeological levels dated to before or directly after the LGM occur in the upper portion of the loess, overlain by the Holocene soil. The investigations at the Moravany-Lopata site have confirmed the usefulness of the anthropogenic indicators in the 0.1–1.0 mm fraction for the identification of occupation levels extending even beyond the area of occurrence of macrofinds and evident type structures. On this basis, a relationship could be established between two occupational levels and two ice-wedge generations in the period from 21.4 to 20 ky. Gravettian settlement in western Slovakia seems to have persisted up to the maximum of the LGM. Population groups representing the end of the shouldered points horizon (pointes à cran) appeared in western Slovakia in the intervals between the formation of large networks of ice wedges. The next settlement phase in that territory falls at about 18–17 ky B.P. This is the Epigravettian settlement, which is culturally unrelated to the shouldered points horizon. © 1998 John Wiley & Sons, Inc.  相似文献   
20.
tWe analyse continuous measurements of groundwater level in two deep wells VS-3 and V-28 at the experimental hydro-meteorological station situated on the NE margin of the Bohemian Massif, central Europe, characterized by the weak intraplate seismic activity. The aim of our study is to examine the relationships between changes in the groundwater level and earthquake occurrence. Based on the tidal and barometric response of the water level, we estimated selected elastic parameters of the observed aquifers: the shear modulus G, the Skempton ratio B, the drained matrix compressibility β and the undrained compressibility βu. Using these parameters and assuming the homogeneous poroelastic material, we derived the sensitivity of the wells to the crustal volume strain. During the observation period from November 1998 to December 2005 we detected in the VS-3 well two pre-seismic steps, related to August 10, 2005 (M = 2.4) and October 25, 2005 (M = 3.3) earthquakes. Amplitudes of the recorded precursory changes (+6 cm and +15 cm) are several times higher than the values predicted from the theoretical precursory crustal strain and the strain sensitivity of the well. Therefore, we presume that the observed pre-seismic water level steps can be attributed to heterogeneity of poroelastic material. We consequently propose the hypothesis of the origin of precursory events based on the presumption of a sensitive site, at which the well is situated.  相似文献   
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