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S. Bilir T. Güver I. Khamitov T. Ak S. Ak K. B. Coşkunoğlu E. Paunzen E. Yaz 《Astrophysics and Space Science》2010,326(1):139-150
We present CCD BV and JHK
s
2MASS photometric data for the open cluster NGC 1513. We observed 609 stars in the direction of the cluster up to a limiting
magnitude of V∼19 mag. The star-count method showed that the centre of the cluster lies at α
2000=04
h
09
m
36
s
, δ
2000=49°28′43″ and its angular size is r=10 arcmin. The optical and near-infrared two-colour diagrams revealed the colour excesses in the direction of the cluster
as E(B−V)=0.68±0.06, E(J−H)=0.21±0.02 and E(J−K
s
)=0.33±0.04 mag. These results are consistent with normal interstellar extinction values. Optical and near-infrared Zero Age
Main-Sequences (ZAMS) provided an average distance modulus of (m−M)0=10.80±0.13 mag, which can be translated into a distance of 1440±80 pc. Finally, using Padova isochrones we determined the
metallicity and age of the cluster as Z=0.015±0.004 ([M/H]=−0.10±0.10 dex) and log (t/yr)=8.40±0.04, respectively. 相似文献
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We present spectroscopic orbits for the active stars HD 82159 (GS Leo), HD 89959, BD +39° 2587 (a visual companion to HD 112733),
HD 138157 (OX Ser), HD 143705, and HD 160934. This paper is a sequel to one published in this journal in 2006, with similar
avowed intention, by Gálvez et al. They showed only graphs, and gave no data, and no orbital elements apart from the periods
(only two of which were correct) and in some cases the eccentricities. Here we provide full information and reliable orbital
elements for all the stars apart from HD 160934, which has not completed a cycle since it was first observed for radial velocity. 相似文献
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Turkey currently lacks a fully functional flood forecasting system (FFS). However, the studies necessary for establishing such a system are still being performed by the Turkish State Meteorological Service. The main purpose of this study was to determine the technical architecture of the FFS intended to be developed in Turkey and to design a flood forecasting and inundation-mapping system integrated with spatial data infrastructure (SDI). Because SDIs provide interoperability among the institutions by enabling collective use of data and services, this enables decision makers to take correct and rapid decisions regarding the forecasting. In the design of the system, the Web services architecture presented by the open geospatial consortium that develops international standards for SDI realizations was taken as a basis. Designed with flexibility and an expandable architecture, the system will enable instant access to up-to-date data from different institutions through Web services and meets the requirements of a real-time FFS. While the criteria requiring the expansion of the designed system were explained, its implementation was left for future studies. 相似文献
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Valentina?MontaldoEmail author Ezio?Faccioli Gaetano?Zonno Aybige?Akinci Luca?Malagnini 《Journal of Seismology》2005,9(3):295-316
In the framework of the 2004 reference seismic hazard map of Italy the amplitude of the strong-motion (expressed in terms
of Peak Horizontal Acceleration with 10% probability of non-exceedence in 50 years, referred to average hard ground conditions)
was computed using different predictive relationships. Equations derived in Italy and in Europe from strong-motion data, as
well as a set of weak and strong-motion based empirical predictive relationships were employed in a logic tree procedure,
in order to capture the epistemic uncertainty affecting ground-motion attenuation. This article describes the adjustments
and conversions required to eliminate the incompatibilities amongst the relations. Particularly significant are distance conversions
and style-of-faulting adjustments, as well as the problems related to the use of regional relations, such as the selection
of a reference depth, the quantification of random variability and the strong-motion prediction. Moreover, a regional attenuation
relationship specific for volcanic areas was also employed, allowing a more realistic evaluation of seismic hazard, as confirmed
by the attenuation of macroseismic intensities. 相似文献
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Naki Akçar Susan Ivy‐Ochs Vasily Alfimov Fritz Schlunegger Anne Claude Regina Reber Marcus Christl Christof Vockenhuber Andreas Dehnert Meinert Rahn Christian Schlüchter 《地球表面变化过程与地形》2017,42(14):2414-2425
In this study, we use isochron‐burial dating to date the Swiss Deckenschotter, the oldest Quaternary deposits of the northern Alpine Foreland. Concentrations of cosmogenic 10Be and 26Al in individual clasts from a single stratigraphic horizon can be used to calculate an isochron‐burial age based on an assumed initial ratio and the measured 26Al/10Be ratio. We suggest that, owing to deep and repeated glacial erosion, the initial isochron ratio of glacial landscapes at the time of burial varies between 6.75 and 8.4. Analysis of 22 clasts of different lithology, shape, and size from one 0.5 m thick gravel bed at Siglistorf (Canton Aargau) indicates low nuclide concentrations: <20 000 10Be atoms/g and <150 000 26Al atoms/g. Using an 26Al/10Be ratio of 7.6 (arithmetical mean of 6.75 and 8.4), we calculate a mean isochron‐burial age of 1.5 ± 0.2 Ma. This age points to an average bedrock incision rate between 0.13 and 0.17 mm/a. Age data from the Irchel, Stadlerberg, and Siglistorf sites show that the Higher Swiss Deckenschotter was deposited between 2.5 and 1.3 Ma. Our results indicate that isochron‐burial dating can be successfully applied to glaciofluvial sediments despite very low cosmogenic nuclide concentrations. Copyright © 2017 John Wiley & Sons, Ltd. 相似文献