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101.
Franco?Braga Marco?Faggella Rosario?Gigliotti Michelangelo?LaterzaEmail author 《Bulletin of Earthquake Engineering》2005,3(3):333-353
The isolation systems are usually made of rubber bearings that are sometimes coupled in hybrid combination with frictional
devices; this is the case of an in-site experimental campaign, performed on a base isolated apartment building in Rapolla
(south of Italy). Several dropout tests at initial displacements up to 17cm allowed to obtain in-site information on the true
dynamic response of the isolation system (building and isolators). The tests carried out allow a comparison between the free
vibration responses of a building, isolated by using a 28 HDRB isolation system only, or an HDRB-Friction Sliders Hybrid one.
The paper highlights the main differences of the response in the superstructure (the structure over the isolation system)
obtained by using only HDRB isolation system, or the Hybrid one (HDRB and Friction Sliders in parallel system). Analysis and
comparisons of experimental data, show the influence of nonlinearities on structural higher modes amplification, especially
observed by using the higher nonlinear Hybrid isolation system. Tests results confirm that, in the case of a regular superstructure,
like the Rapolla building, the isolation system nonlinearities influence the structural response. 相似文献
102.
Michele Bossi Gianantonio Guerrero Luciano Mantegazza Marco Scardia 《Astrophysics and Space Science》1980,72(2):433-437
Photoelectric observations of the shell staro And, obtained in 1979, are presented. The star shows variations of some hundredth of magnitudes during a few hours. The trend to retake the values of the luminosity and colour indices prior to the reduction happened between JD 42,714-27, seems to continue. We also give a qualitative model which explains satisfactorily the main features observed after the 1975 shell episode. 相似文献
103.
Michele Bossi Gianantonio Guerrero Luciano Mantegazza Marco Scardia 《Astrophysics and Space Science》1981,79(2):463-468
Photoelectric observations of the suspected Delta-Scuti star HR 5492 are given. The present data do not show any light variation greater than 0.01 mag. In spite of the very small light variations, the data analysis shows the presence of two periodicities, which are statistically significant. While the longest period (1.
.
d
296) cannot be justified with the present data, the shorter one (0.
.
d
044) is in excellent agreement with the hypothesis of an F4V star that is radially pulsating in the fundamental mode, even if this star is well outside the cold border of the instability strip. 相似文献
104.
Fabrizio Nestola Tiziana Boffa Ballaran Christian Liebske Marco Bruno Mario Tribaudino 《Physics and Chemistry of Minerals》2006,33(6):417-425
The volume variation as a function of pressure along the jadeite–aegirine solid solution was determined at room temperature up to pressures between 6.5 and 9.7 GPa by single-crystal X-ray diffraction. The unit-cell volumes collected at room pressure for the different compositions indicate a slight deviation from linearity along the join. The pressure–volume data have been fitted using a third-order Birch-Murnaghan equation of state (BM3-EoS). The bulk modulus, K
T0, varies from 134.0(7) GPa for pure jadeite to 116.1(5) GPa for pure aegirine. Its evolution with composition along the join is not linear and can be described by the following second order polynomial:
The value of the first pressure derivative K′ is close to 4 for all the samples investigated and can be used in a BM3-EoS to determine the volume variations of these pyroxenes up to 7–10 GPa. Along the join the highest compressibility among the crystallographic directions is always observed along a, however, the compression along b is the most affected by compositional changes. The strain ellipsoid analysis indicates that the major compression occurs on the (0 1 0) plane along a direction at about 145° to the c axis (from c to a). The anisotropy of the compression increases with increasing the aegirine component, as confirmed by the analysis of both the axial compressibility and the strain tensor. 相似文献
(1) |
105.
Luísa D.V.Carvalho Tiago Jalowitzki Ricardo Scholz Guilherme O.Gonalves Marcelo Peres Rocha Rogério Silvestre Pereir Cristiano Lana Marco Paulo de Castro Gláucia Queiroga Reinhardt A.Fuck 《地学前缘(英文版)》2022,(1):182-203
We present major and trace element compositions of mineral concentrates comprising garnet xenocrysts,ilmenite,phlogopite,spinel,zircon,and uncommon minerals (ti... 相似文献
106.
European Geostationary Navigation Overlay Service (EGNOS) is a satellite-based system developed to improve the performance
of GPS in the European region. It not only enhances the estimated positioning accuracy but also provides an integrity solution.
We assess the EGNOS performance through analysis of real measurements, performed in different road user environments. We investigate
the use of the integrity concept in future Global Navigation Satellite System (GNSS)-based applications in the road environment,
considering both suburban and dense urban areas. The analysis is motivated by the fact that there is an increasing number
of road applications, such as billing system, transportation of dangerous goods, remote tracking of trucks and snow plows,
fleet management and “pay as you go” car insurances, where the system liability has to be guaranteed. The scope of the analysis
is to investigate to which extent the use of the integrity concept can be used for such purpose; the assessment is based on
real measurement campaigns in representative environments, providing statistical results in terms of accuracy and integrity,
and in a wider sense of the feasibility of the use of EGNOS for augmenting the reliability of GNSS positioning for road applications. 相似文献
107.
AGUIRRE-SALADO Carlos Arturo TREVIO-GARZA Eduardo Javier AGUIRRE-CALDERóN Oscar Alberto JIMéNEZ-PéREZ Javier GONZáLEZ-TAGLE Marco Aurelio VALDEZ-LAZALDE José René MIRANDA-ARAGóN Liliana AGUIRRE-SALADO Alejandro Iván 《地理学报(英文版)》2012,22(4):669-680
Spatially-explicit estimation of aboveground biomass(AGB) plays an important role to generate action policies focused in climate change mitigation,since carbon(C) retained in the biomass is vital for regulating Earth’s temperature.This work estimates AGB using both chlorophyll(red,near infrared) and moisture(middle infrared) based normalized vegetation indices constructed with MCD43A4 MODerate-resolution Imaging Spectroradiometer(MODIS) and MOD44B vegetation continuous fields(VCF) data.The study area is located in San Luis Potosí,Mexico,a region that comprises a part of the upper limit of the intertropical zone.AGB estimations were made using both individual tree data from the National Forest Inventory of Mexico and allometric equations reported in scientific literature.Linear and nonlinear(expo-nential) models were fitted to find their predictive potential when using satellite spectral data as explanatory variables.Highly-significant correlations(p = 0.01) were found between all the explaining variables tested.NDVI62,linked to chlorophyll content and moisture stress,showed the highest correlation.The best model(nonlinear) showed an index of fit(Pseudo-r2) equal to 0.77 and a root mean square error equal to 26.00 Mg/ha using NDVI62 and VCF as explanatory variables.Validation correlation coefficients were similar for both models:lin-ear(r = 0.87**) and nonlinear(r = 0.86**). 相似文献
108.
Assessment of CMIP3 climate models and projected changes of precipitation and temperature in the Yangtze River Basin, China 总被引:1,自引:0,他引:1
The projected changes of precipitation and temperature in the Yangtze River Basin in the 20th Century from 20 models of the CMIP3 (phase 3 of the Coupled Model Inter-comparison Project) dataset are analyzed based on the observed precipitation and temperature data of 147 meteorological stations in the Yangtze River Basin. The results show that all models tend to underestimate the annual mean temperature over the Yangtze River Basin, and to overestimate the annual mean precipitation. The temporal changes of simulated annual mean precipitation and temperature are broadly comparable with the observations, but with large variability among the results of the models. Most of the models can reproduce maximum precipitation during the monsoon season, while all models tend to underestimate the mean temperature of each month over the Yangtze River Basin. The Taylor diagram shows that the differences between modeled and observed temperature are relatively smaller as compared to differences in precipitation. For a detailed investigation of regional characteristics of climate change in the Yangtze River Basin during 2011–2050, the multi-model ensembles produced by an upgraded REA method are carried out for more reliable projections. The projected precipitation and temperature show large spatial variability in the Yangtze River Basin. Mean precipitation will increase under the A1B and B1 scenarios and decrease under the A2 scenario, with linear trends ranging from ?21 to 28.5?mm/decade. Increasing mean temperature can be found in all scenarios with linear trends ranging from 0.15 to 0.48°C/decade. Grids in the head region of the Jingshajiang catchment show distinct increasing trends for all scenarios. Some physical processes associated with precipitation are not well represented in the models. 相似文献
109.
Christian Wolf Alfonso Aragón-Salamanca Michael Balogh Marco Barden Eric F. Bell Meghan E. Gray Chien Y. Peng David Bacon Fabio D. Barazza Asmus Böhm John A. R. Caldwell Anna Gallazzi Boris Häußler Catherine Heymans Knud Jahnke Shardha Jogee Eelco van Kampen Kyle Lane Daniel H. McIntosh Klaus Meisenheimer Casey Papovich Sebastian F. Sánchez y Taylor Lutz Wisotzki Xianzhong Zheng 《Monthly notices of the Royal Astronomical Society》2009,393(4):1302-1323
We investigate the properties of optically passive spirals and dusty red galaxies in the A901/2 cluster complex at redshift ∼0.17 using rest-frame near-ultraviolet–optical spectral energy distributions, 24-μm infrared data and Hubble Space Telescope morphologies from the STAGES data set. The cluster sample is based on COMBO-17 redshifts with an rms precision of σ cz ≈ 2000 km s−1 . We find that 'dusty red galaxies' and 'optically passive spirals' in A901/2 are largely the same phenomenon, and that they form stars at a substantial rate, which is only four times lower than that in blue spirals at fixed mass. This star formation is more obscured than in blue galaxies and its optical signatures are weak. They appear predominantly in the stellar mass range of log M * /M⊙ =[10, 11] where they constitute over half of the star-forming galaxies in the cluster; they are thus a vital ingredient for understanding the overall picture of star formation quenching in clusters. We find that the mean specific star formation rate (SFR) of star-forming galaxies in the cluster is clearly lower than in the field, in contrast to the specific SFR properties of blue galaxies alone, which appear similar in cluster and field. Such a rich red spiral population is best explained if quenching is a slow process and morphological transformation is delayed even more. At log M * /M⊙ < 10 , such galaxies are rare, suggesting that their quenching is fast and accompanied by morphological change. We note that edge-on spirals play a minor role; despite being dust reddened they form only a small fraction of spirals independent of environment. 相似文献
110.
Marco Delbó 《Earth, Moon, and Planets》2009,105(2-4):235-247
Applications of the 42m European Extremely Large Telescope (E–ELT) for the physical characterization of asteroids is presented. In particular, this work focuses on the determination of sizes and other physical properties of asteroids from measurements of their heat emission in the thermal infrared (>5 μm). Here we show that E–ELT will be best suited for the physical characterization of some selected asteroids of particular interest, as for instance: (i) targets of sample return missions to near-Earth Asteroids (NEAs); (ii) km and sub-km binary asteroids for which size information will allow their bulk density to be derived; (iii) sizes and values of the thermal inertia of potentially hazardous asteroids (PHAs). These two parameters both affect the Yarkovsky effect, which plays a role in the orbital evolution of km sized asteroids and represents a large source of uncertainty in the Earth impact probability prediction of some PHAs. Thermal inertia is also a sensitive indicator for the presence or absence of thermal insulating regolith on the surface of atmosphere-less bodies. Knowledge of this parameter is thus important for the design and the development of lander- and sample return-missions to asteroids. The E–ELT will also be able to spatially resolve asteroids and detect binaries in a range of sizes that are at present not accessible to present day adaptive optics. 相似文献