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201.
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
202.
Irma Kveladze Menno-Jan Kraak Corné P.J.M. Van Elzakker 《International journal of geographical information science》2015,29(11):2001-2016
This paper reports the results of an empirical usability experiment on the performance of the space-time cube in a GeoVisual analytics environment. It was developed to explore movement data based on the requirements of human geographers. The interactive environment consists of multiple coordinated views incorporating three graphical representations. For the experiment, two groups of the user, domain experts and non-domain experts, had to execute several map-use tasks to answers specific question. The data collected during the experiment were analysis resulting in a set of usability metrics related to the effectiveness, efficiency and user satisfaction of developed application. The comparison of both groups showed that domain experts were able to operate the visual analytical environment more effectively and efficiently due to their interest to explore their data. The user feedback derived from the analysis of both experiments was further processed for the improvement of the application. 相似文献
203.
Pierre Horgue Romain Guibert Hervé Gross Patrice Creux Gérald Debenest 《Computational Geosciences》2015,19(6):1159-1169
This work presents a new subdivision method to upscale absolute permeability fields. This process, called two-step method, consists in (i) solving micro-scale equations on subdomains obtained from the full domain regular decomposition and (ii) solve a second upscaling with Darcy’s law on the permeability fields obtained in the first step. The micro-scale equations used depend on the case studied. The two-step upscaling process is validated on randomly generated Darcy-scale permeability fields by measuring the numerical error induced by upscaling. The method is then applied to real domains obtained from sandstone micro-tomographic images. The method specificities due to pore-space structure are discussed. The main advantage of the two-step upscaling method resides in the drastic reduction of computational costs (CPU time and memory usage) while maintaining a numerical error similar to that of other upscaling procedures. This new upscaling method may improve permeability predictions by the use of finer meshes or larger sample volumes. 相似文献
204.
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206.
Human-induced coastal landslide reactivation. Monitoring by PSInSAR techniques and urban damage survey (SE Spain) 总被引:1,自引:1,他引:0
207.
J. C. Morales J.-P. Beaulieu V. Coudé du Foresto M. Ollivier I. Ortega Castello R. Clédassou J. Jaubert P. Van-Troostenberghe R. Varley I. P. Waldmann E. Pascale M. Tessenyi 《Experimental Astronomy》2015,40(2-3):655-670
The Exoplanet Characterization Observatory (EChO) is a concept of a dedicated space telescope optimized for low-resolution transit and occultation spectroscopy to study the exoplanet diversity through the composition of their atmospheres. The scope of this paper is to answer the following question: Can we schedule a nominal EChO mission, with targets known today (in mid 2013), given the science requirements, realistic performances and operational constraints? We examine this issue from the point of view of duration of the mission and the scheduling restrictions with a sample of exoplanet systems known nowadays. We choose different scheduling algorithms taking into account the science and operational constraints and we verified that it is fairly straightforward to schedule a mission scenario over the lifetime of EChO compliant with the science requirements. We identified agility as a critical constraint that reduces significantly the efficiency of the survey. We conclude that even with known targets today the EChO science objectives can be reached in the 4.5 years duration of the mission. We also show that it is possible to use gaps between exoplanet observations, to fit the required calibration observations, data downlinks and station keeping operations or even to observe more exoplanet targets to be discovered in the coming years. 相似文献
208.
E. Pascale I. P. Waldmann C. J. MacTavish A. Papageorgiou A. Amaral-Rogers R. Varley V. Coudé du Foresto M. J. Griffin M. Ollivier S. Sarkar L. Spencer B. M. Swinyard M. Tessenyi G. Tinetti 《Experimental Astronomy》2015,40(2-3):601-619
EChOSim is the end-to-end time-domain simulator of the Exoplanet Characterisation Observatory (EChO) space mission. EChOSim has been developed to assess the capability of the EChO mission concept to detect and characterise the atmospheres of transiting exoplanets. Here we discuss the details of the EChOSim implementation and describe the models used to represent the instrument and to simulate the detection. Software simulators have assumed a central role in the design of new instrumentation and in assessing the level of systematics affecting the measurements of existing experiments. Thanks to its high modularity, EChOSim can simulate basic aspects of several existing and proposed spectrometers including instruments on the Hubble Space Telescope and Spitzer, ground-based and balloon-borne experiments. A discussion of different uses of EChOSim is given, including examples of simulations performed to assess the EChO mission. 相似文献
209.
Bhawan Singh Mustapha El Maayar Pierre André Jean‐Pierre Thouez Christopher Bryant Denis Provençal 《大气与海洋》2013,51(2):379-399
Abstract This study, using a climate change scenario generated by the Canadian Climate Centre (CCC) general circulation model (GCM) examines the impacts of such a climate change on agriculture in southern Quebec. Using a crop model from the Food and Agriculture Organization (FAO), yield responses of a variety of cereals, legumes, oleaginous and special crops to climate change are analysed and discussed. Results show that under the 2 × CO2 climate scenario the growing season would be longer and accumulation of corn heat units and growing degree days would be more important than under actual climate (1961–1990). One of the more important results of this study is that, on the one hand yield of C3 cereals would be lower and that of C4 cereals higher in most agricultural regions. On the other hand, the direct fertilisation effect of increased CO2 is not considered. It must be cautioned however that we can not generalise results obtained for one legume crop to all legumes. 相似文献
210.
Abstract Numerical transport schemes used in atmospheric models only approximate the evolution of the real mass continuity equation. The inaccuracies introduced by discretization schemes result, amongst other things, in the appearance of fictitious “holes” in the mass field, i.e. places where the concentration is locally negative. In this article we compare the behaviour of various numerical schemes that are commonly used in atmospheric models, the remedies that are often applied to prevent the appearance of unphysical holes, and their side effects on the evolution of a transported field. 相似文献