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111.
The contribution of PSInSAR interferometry to landslide hazard in weak rock-dominated areas 总被引:1,自引:0,他引:1
In the Grande da Pipa river basin, north of Lisbon, 64 % of the total number of landslides inventoried is totally or partially included in a lithological unit composed by marl, clay, and sandstone intercalation complex that is present in 58 % of the study area. The Persistent Scatterer synthetic aperture radar interferometry technique is applied to a data set of TerraSAR-X SAR images, from April of 2010 to March of 2011, firstly to the Laje-Salema test site and further exported to the Grande da Pipa river basin. This work’s specific objectives are the following: (i) to assess the potential of the Persistent Scatterer displacement maps to the identification of new landslides/unstable areas and in the redefinition of landslide limits, (ii) to update the landslide state of activity, and (iii) to evaluate the capacity of the Persistent Scatterer deformation maps in assessing landslide susceptibility at the regional scale. Based on this approach, it was possible to increment the number of landslides and to redefine the landslide limits in the test site in 3.8 %. For 39 landslides, it was possible to update the landslide state of activity, in particular from dormant to reactivated or dormant-reactivated (23 landslides) or from stabilized to reactivated (5 landslides). Landslide susceptibility map based in Persistent Scatterer deformation rates, independently validated with a deep rotational slide map, obtained the best value of area under the curve (0.668). 相似文献
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Jaime A. Santos Pedro Chitas Isabel Lopes Carlos Sousa Oliveira Isabel Moitinho de Almeida João Carlos Nunes 《Soil Dynamics and Earthquake Engineering》2011
The Azores archipelago is located at the North America, Eurasia and Africa triple junction and shows seismicity and volcanism typical of an active plate boundary. Terceira Island has been affected by several damaging earthquakes being the 1980 January 1st event (M=7.2) the strongest in Azores during the last century. 相似文献
114.
Edmilson Helton Rios Paulo Frederico de Oliveira RamosVinicius de França Machado Giovanni Chaves StaelRodrigo Bagueira de Vasconcellos Azeredo 《Journal of Applied Geophysics》2011,75(4):631-637
This study explores the application of the partial least squares regression (PLSR) technique to rock permeability prediction from nuclear magnetic resonance (NMR) relaxation data. A total of 68 Brazilian sandstone cores selected from reservoirs and outcrop analogs were fully saturated and analyzed by NMR. The permeability of the cores ranged from 0.007 to 9,800 mD. From their 1H transverse relaxation times (T2) measured at 2 MHz, two PLSR models were developed for the relaxation spectra and the raw relaxation curves. Both models led to more uniform and accurate predictions (RMSE = 0.47 and 0.50 log mD, respectively) compared with the classical Kenyon model (RMSE = 0.78 log mD). 相似文献
115.
José Maria Santos Luís Reino João Oliveira Paulo Pinheiro Pedro Raposo Almeida Rui Cortes Maria Teresa Ferreira 《Aquatic Sciences - Research Across Boundaries》2011,73(2):233-245
Knowledge of the distribution of species life stages at multiple spatial scales is fundamental to both a proper assessment
of species management and conservation programmes and the ability to predict the consequences of human disturbances for river
systems. The habitat requirements of three native cyprinid species—the Iberian barbel Barbus bocagei Steindachner, the Iberian straight-mouth nase Pseudochondrostoma polylepis (Steindachner), and the Northern straight-mouth nase Pseudochondrostoma duriense (Coelho)—were examined at 174 undisturbed or minimally disturbed sites in 8 river catchments across western Iberia, by modelling
occurrence and counts of species life stages at two spatial scales—large (regional) and instream (local)—using hurdle models.
All the life stages of the barbel showed a negative association with upstream high-gradient river reaches, whereas juvenile
P. duriense favoured such areas. Stream width and openness were negatively related with the occurrence of juvenile and small adult barbel,
but not with large adults. Juvenile nase, on the other hand, were found to be mainly confined to fast-flowing habitats with
high instream cover and coarser substrata. Advanced life stages of the barbel were mainly associated with the “pure” regional
and shared components, whereas the purely local attributes accounted for much of the model variation among nases, in particular
juveniles, and juvenile barbel. The results of this study are useful for setting or refining management goals, and highlight
the need to separately consider life stages when performing conservation-related studies of species distribution. 相似文献
116.
The present work reports on an in situ experimental test campaign carried out on abandoned traditional masonry houses after the 9th July 1998 earthquake that seriously hit the Faial island of Azores. For the testing purposes, an experimental test setup was developed based on a self‐equilibrated scheme, which is herein described reporting on the advantages and drawbacks of this in situ test setup. Five specimens were tested aiming at characterizing the out‐of‐plane behavior of stone masonry walls and strengthening solutions recommended for post‐earthquake interventions. A detailed comparison between solutions' efficiency is presented including a cost vs benefit analysis. In order to assess the efficiency of the developed test setup for other applications on stone masonry walls, an in‐plane test on an existing URM panel is also presented. Several related issues are discussed, namely the advantages of dealing with the real boundary conditions and the capacity of providing valuable information of the response, as well as a detailed analysis of the obtained results. The authors believe that this work provides an increase in knowledge on the seismic behavior of the existing masonry constructions, resulting from the development of an in situ test setup and the efficiency quantification of strengthening solutions. Therefore, the work is thought to positively contribute for the preservation of architectural heritage and for its seismic vulnerability reduction. Copyright © 2010 John Wiley & Sons, Ltd. 相似文献
117.
The behaviour of an embankment built on normally consolidated soft soil reinforced with deep mixing columns is studied using a coupled soil–water formulation. The numerical predictions are analysed in terms of settlements, increments in vertical effective stresses and excess pore pressures. Firstly, the effectiveness of the use of deep mixing columns is studied. Afterwards, a parametric analysis is performed to study the influence on the soil-columns system of the replacement ratio (columns’ spacing), the deformability of the embankment and columns, and the coefficient of vertical permeability of the columns. 相似文献
118.
Isotropic and homogeneous cosmological models with a perfect fluid cource in Brans-Dicke theory are investigated from the point of view of dynamical system theory.Work partially supported by CNPq (Brazil). 相似文献
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Carlos Roberto Sanquetta Ana Paula Dalla Corte Alexandre Behling Luani Rosa de Oliveira Piva Sylvio Péllico Netto Aurélio Lourenço Rodrigues Mateus Niroh Inoue Sanquetta 《Carbon balance and management》2018,13(1):25