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101.
Castro-Miguel Rutilio Legorreta-Paulín Gabriel Bonifaz-Alfonzo Roberto Aceves-Quesada José Fernando Castillo-Santiago Miguel Ángel 《Natural Hazards》2022,113(1):767-788
Natural Hazards - Little study has been done on the effect of the pixel neighborhood information when modeling landslide susceptibility using multiple logistic regression (MLR). The present... 相似文献
102.
103.
Elena M. Blanter Jean-Louis Le Mouël Mikhail G. Shnirman Vincent Courtillot 《Solar physics》2014,289(11):4309-4333
We apply a Kuramoto model of nonlinear coupled oscillators to the simulation of slow variations of the phase difference between sunspot number [R I ] and geomagnetic indices [aa and ζ]. The Kuramoto model is described for the particular case of two oscillators connected by symmetric coupling with quasi-stationary behavior, and its properties are investigated. By solving an inverse problem, we reconstruct the evolution of the couplings between pairs of indices [R I and aa, R I and ζ, aa and ζ], and interpret these in terms of the physics of the solar dynamo. The de-correlation between R I and geomagnetic indices found in Solar Cycle 20 by Le Mouël et al. (J. Geophys. Res. 117, A09103, 2012) is successfully reproduced by the Kuramoto model and corresponds to the alternation of the leading oscillator. Application of the Kuramoto model to the cross-correlations [C(R I ,ζ) and C(aa,ζ)] for ζ-indices computed in eight geomagnetic stations shows the latitudinal dependence of the mean phase difference. We discuss these results in terms of the solar-wind contribution to local geomagnetic indices [ζ]. 相似文献
104.
Elena DzifčÁKOVÁ 《Solar physics》2006,234(2):243-256
Changes in the excitation equilibrium of Feviii – Fe xv in the solar corona due to the electron non-thermal κ-distribution
are studied. The shape of the distribution affects the electron excitation rate and thus the relative intensities of the spectral
lines. Since the shape of the electron distribution function influences also the ionization equilibrium of Fe, both effects
change the final intensities of the lines. Possibilities for diagnostics of the shape of the electron distribution in the
solar corona are discussed. Synthetic spectrum of Fe for T = 1.58× 106 K and ne = 108 cm−3 is shown together with the synthetic spectra computed with DEM for the quiet Sun. 相似文献
105.
Elena B Volynets Svetlana A Schorokhova Ge Sun 《东北亚地学研究》2006,9(1):1-12
IntroductionThe Late Triassic strata andflora developed andwell outcropped in southern Pri morye,Russia.Thestrata are marine and non-marine alternate for eachother and yield abundant mollusk and plant fossilsinwhich the Late Triassic Mongugai flora is well-known in the world.Kryshtofovich(1910,1921,1924)and Kryshtofovich&Prynada(1932)studiedthis florainthe earlier ti me,and consequently,Sre-brodolyskaja(1958,1961,1968),Schorokhova(1975,1977,1997,2004)and Krassilov&Schorokhova(1970,1975)ma… 相似文献
106.
107.
Daniel Rosa-González Denis Burgarella Kirpal Nandra Daniel Kunth Elena Terlevich † Roberto Terlevich † 《Monthly notices of the Royal Astronomical Society》2007,379(1):357-369
We have combined multiwavelength observations of a selected sample of star-forming galaxies with galaxy evolution models in order to compare the results obtained for different star formation rate (SFR) tracers and to study the effect that the evolution of the star-forming regions has on them. We also aimed at obtaining a better understanding of the corrections due to extinction and nuclear activity on the derivation of the SFR. We selected the sample from Chandra data for the well studied region Chandra Deep Field -South (CDFS) and chose the objects that also have ultraviolet (UV) and infrared (IR) data from Galaxy Evolution Explorer ( GALEX ) and Great Observatories Origins Deep Survey (GOODS) Spitzer , respectively.
Our main finding is that there is good agreement between the extinction corrected SFR(UV) and the SFR(X), and we confirm the use of X-ray luminosities as a trustful tracer of recent star formation activity. Nevertheless, at SFR(UV) larger than about 5 M⊙ yr−1 there are several galaxies with an excess of SFR(X) suggesting the presence of an obscured active galactic nucleus (AGN) not detected in the optical spectra. We conclude that the IR luminosity is driven by recent star formation even in those galaxies where the SFR(X) is an order of magnitude higher than the SFR(UV) and therefore may harbour an AGN. One object shows SFR(X) much lower than expected based on the SFR(UV); this SFR(X) 'deficit' may be due to an early transient phase before most of the massive X-ray binaries were formed. An X-ray deficit could be used to select extremely young bursts in an early phase just after the explosion of the first supernovae associated with massive stars and before the onset of massive X-ray binaries. 相似文献
Our main finding is that there is good agreement between the extinction corrected SFR(UV) and the SFR(X), and we confirm the use of X-ray luminosities as a trustful tracer of recent star formation activity. Nevertheless, at SFR(UV) larger than about 5 M
108.
Different methods are proposed and tested for transforming a nonlinear differential system, and more particularly a hamiltonian one, into a map without having to integrate the whole orbit as in the well known Poincaré map technique. We construct piecewise polynomial maps by coarse-graining the phase surface of section into parallelograms using values of the Poincaré maps at the vertices to define a polynomial approximation within each cell. The numerical experiments are in good agreement with the standard map taken as a model problem. The agreement is better when the number of vertices and the order of the polynomial fit increase. The synthetic mapping obtained is not symplectic even if at vertices there is an exact interpolation. We introduce a second new method based on a global fitting . The polynomials are obtained using at once all the vertices and fitting by least square polynomes but in such a way that the symplectic character is not lost. 相似文献
109.
110.
In Spain, the birth of interest in the nation's industrial heritage dates from the 1980s and occurred alongside the process of deindustrialization. Policies concerning derelict industrial sites have shifted gradually from destruction to preservation, rehabilitation, and enhancement, and industrial heritage enhancement projects are now widespread in the country. However, a clear mismatching has arisen between institutional and academic initiatives and local communities, which exhibit widespread disinterest in or even rejection of industrial remains. This problematic situation can be related to the utilization of industrial heritage as an economic resource without paying much attention to its connections with memory and identity. Also, the mismatching is due to a positivist approach to industrial heritage whereby the monument and the museum are prioritized. We argue that projects which consider industrial remains as part of cultural landscapes might shorten the gap between the institutional and economic side of industrial heritage and its identity‐building and popular facets. 相似文献