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941.
István Kovács Attila Demény György Czuppon Christophe Lécuyer Francois Fourel Qun-Ke Xia Jia Liu Zsanett Pintér Edit Király Kálmán Török Ábel Szabó Etienne Deloule György Falus Tamás Fancsik Zoltán Zajacz Judit Sándorné Kovács Beatrix Udvardi 《Contributions to Mineralogy and Petrology》2016,171(5):38
942.
Jaromír Janský Vladimír Plicka Helene Lyon-Caen Oldřich Novotný 《Journal of Seismology》2007,11(2):199-204
We determine the velocities in an upper crustal model, composed of three homogeneous layers, for one subregion of the western
part of the Gulf of Corinth, NE of the town of Aigion, Greece. We have used local events that occurred there in the year 2001
and were recorded by the Corinth Rift Laboratory Network. Weighted P and S arrival time residuals are minimized using the Neighbourhood Algorithm of Sambridge (1999), combined with the grid search
for source locations. The resolution of the inversion is tested by delete-one jackknifing. The model obtained is compared
with some other models derived or applied to the subregion. A fast velocity increase between depths of 5 and 7 km is confirmed
as the major structural element. 相似文献
943.
Rock joint constitutive modelling is discussed through two new rock joint constitutive relations and a discrete numerical model. Regarding the constitutive relations, we emphasise the number of ‘tensorial zones’, that is, domains of constitutive incremental linearity; they involve four zones for the first (called ‘quadrilinear’) and an infinite number for the second one (called ‘incrementally nonlinear’). Using these formulations, a large class of loading paths can be considered. Hardening through shearing and relations between the normal and tangential directions of the joint (e.g., dilatancy) can be described. Their predictive abilities are checked. Plastic features are included even if the relations are defined outside the elasto‐plastic formalism. These relations obey, hence, the physical evidence as the plastic limit criterion and flow rule. The flow rule is nonassociated, and the corresponding link with the nonsymmetry of the constitutive matrix is examined. Comparisons between the two relations and the discrete numerical model, that is, a direct numerical simulation, which is fundamentally different, also are discussed within the context of infilled rock joints. Copyright © 2011 John Wiley & Sons, Ltd. 相似文献
944.
The new Antarctic TALDICE ice core (72° 49′ S, 159° 11′ E, 1620 m depth), containing abundant primary tephras, provides the opportunity to elucidate the late Quaternary volcanic history of the south polar region, as well as to broaden the East Antarctic tephrostratigraphic framework. Here grain size and glass compositional data for representative tephra layers from the last 70 ka core section are used for source identification. Results point to origin of layers from centres of the Melbourne Volcanic Province (McMurdo Volcanic Group), located ~250 km from the coring site. Occurrence of tephra layers within the ice core record suggests that explosive activity in the identified source was not constant over the considered period, with a minimum of activity between 20 and 35 ka, and increased activity back to 65 ka. In addition to palaeovolcanic implications, the TALDICE tephra layers offer prospects for firm correlations between diverse widely separated palaeoarchives and for accurate dating of the Antarctic climatic record. Copyright © 2010 John Wiley & Sons, Ltd. 相似文献
945.
Osvaldo Salazar Abraham Joel Ingrid Wesström Harry Linnér R. Wayne Skaggs 《水文研究》2010,24(26):3837-3851
The field hydrology model DRAINMOD integrated with Arc Hydro in geographical information system (GIS) framework (Arc Hydro–DRAINMOD) was used to simulate the hydrological response of a coastal watershed in southeast Sweden. Arc Hydro–DRAINMOD uses a distributed approach to route water from each field edge to the watershed outlet. In the framework the Arc Hydro data model was used to describe the stream network in the watershed and to connect the individual simulated DRAINMOD‐field outflow time series from each plot using Arc Hydro schema‐links features, which were summed at Arc Hydro schema‐nodes features along the stream network to generate the stream network flow. Hydrology data collected during six periods between 2003 and 2008 were used to test Arc Hydro–DRAINMOD and its performance was evaluated by considering uncertainties in model inputs using generalized likelihood uncertainty estimation (GLUE). The GLUE estimates obtained (uncertainty bands 5% and 95%) agreed satisfactorily with measured monthly discharges. The percentage of time in which the observed discharges were bracketed by the uncertainty bands was 88% in calibration periods and 75% in validation periods. Although monthly time step simulations showed good agreement with observed discharges during the two main discharge events in spring, the contradictory daily time step results indicate that the watershed response simulations on a daily basis need to be improved. The uncertainty analysis showed that in periods of higher discharge, such as spring periods, the uncertainty in prediction was higher. It is important to note that these uncertainty estimations using the GLUE procedure include the uncertainties in measured discharge values, model inputs, boundary conditions and model structures. It was estimated that stream baseflow represented 42% of the total watershed discharge, but further research is needed to confirm this. These results show that the new Arc Hydro–DRAINMOD framework is applicable for predicting discharge from artificially drained watersheds in southeast Sweden. Copyright © 2010 John Wiley & Sons, Ltd. 相似文献
946.
BELEJMiroslaw ZROBEKSabina LIANGLiu-ke 《中国地理科学(英文版)》2002,12(4):366-372
The conception of an efficient cadastral system is an important element in the development of each coun-try. It is crucial for the efficient operation of the real estate market—the security and liberty of making transactions, register-ing a property, planning operations, the introduction of an ad valorem tax on property and more rational use of space. InEurope there are different types of cadastral systems, because the countries in Europe have different cultural back-grounds, different economical and social backgrounds. Through the centuries, many types of cadastral systems evolvedand their differences often depend upon local cultural heritage, physical geography, land use, technology, etc. Compara-tive analyses of cadastral systems have been the subjects of many publications and studies in world literature. It was as-sessed that the useful tools in conducting comparative analyses of various cadastral systems include the procedures of statisti-cal inference. This paper presents the results of a project to compare the performance of ten cadastral systems international-ly by creating appropriate integrated indicators of a cadastral system using statistical technique. Such indicators willmake it possible to compare different cadastral systems and present them hierarchically in relation to their quality, struc-ture, as well as legal, organizational and technological solutions. From a good number of methods available, techniquesoriginating from two spheres of statistic inference were selected: distribution free methods and multivariate analysis meth-ods. For analyses with the distribution free methods, FRIEDMAN‘‘s test (FRIENDMAN‘‘s non-parametric variance analy-sis) as well as KENDALL‘‘s test ( KENDALL‘‘s compatibility ratio) were selected. For analyses with the multivariate analy-sis methods, factor analysis was selected. 相似文献
947.
Marinella A. LAURENZI Giulio BIGAZZI Maria Laura BALESTRIERI Vladimìr BOUKA 《Meteoritics & planetary science》2003,38(6):887-893
Abstract— A new 40Ar/39Ar data set is presented for tektites from the Central European strewn field (moldavites). This is the only strewn field that is entirely situated in a continental environment and still characterized by scattered ages (14–15.3 Myr). The main objectives of the study were to define more precisely the moldavite formation age and provide a good calibration for a glass standard proposed for fission‐track dating. The laser total fusion ages obtained on chips from 7 individual specimens from the Southern Bohemian and Moravian subfields are restricted to a narrow interval of time, with an average of 14.34 ± 0.08 Myr relative to the 27.95 ± 0.09 Myr of the Fish Canyon Tuff biotite. This result gives a more precise age not only for the tektite field but also for its producing impact. If the genetic link between the moldavites and the Nördlinger Ries impact crater is maintained, then this new age has to be considered a reliable estimate for the Ries crater also. This new value places the formation of Central European tektites within the Lower Serravallian period in the latest geologic timescales. Evidence of their impact products, such as glass spherules or shocked minerals, can, therefore, be sought in sedimentary marine formations in a more precisely defined age interval. 相似文献
948.
W. J. Chaplin Y. Elsworth G. R. Isaak B. A. Miller R. New B. Pintér † 《Monthly notices of the Royal Astronomical Society》2005,359(2):607-614
We report monitoring observations of 20 high-luminosity active galactic nuclei (AGN), 12 of which are radio-quiet quasars (RQQs). Intranight optical variability (INOV) was detected for 13 of the 20 objects, including 5 RQQs. The variations are distinctly stronger and more frequent for blazars than for the other AGN classes. By combining these data with results obtained earlier in our programme, we have formed an enlarged sample consisting of 9 BL Lacs, 19 RQQs and 11 lobe-dominated radio-loud quasars (RLQs). The moderate level of rapid optical variability found for both RQQs and radio lobe-dominated quasars (LDQs) argues against a direct link between INOV and radio loudness. We supplemented the present observations of 3 BL Lacs with additional data from the literature. In this extended sample of 12 well observed BL Lacs, stronger INOV is found for the EGRET detected subset. 相似文献
949.
Ö. L. Deĝirmenci Ö. Gülmen C. Sezer N. Güdür A. Erdem 《Astrophysics and Space Science》1996,241(2):327-332
Photoelectric B and V light curves of the eclipsing binary V1425 Cygni were analyzed by the method of Wilson-Devinney. The system was found to be a semi-detached binary where the secondary component (less massive and cooler) fills its Roche lobe. 相似文献
950.