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11.

On September 7, 2017, at 23:49 h (local time), a Mw8.2 intermediate-depth normal-fault earthquake occurred in the Gulf of Tehuantepec, 133 km away from Pijijiapan, Chiapas, and about 700 km away from Mexico City. This event caused 95 fatalities and severe damage to different types of structures located close to the epicenter. The main objective of this work is to present observed damages caused in the state of Oaxaca by this earthquake, which were mainly concentrated in self-built houses and historical and ancient buildings. The locations visited by the reconnaissance team of the Institute of Engineering from UNAM in Oaxaca included Salina Cruz, Tehuantepec, Ixtaltepec, Juchitán, Huatulco and La Ventosa.

  相似文献   
12.
Rodríguez  Oriol  Bech  Joan 《Natural Hazards》2020,104(1):1021-1038
Natural Hazards - High-resolution aerial imagery may provide very detailed information about strong-convective wind events, which can be very useful to enhance and make more robust severe weather...  相似文献   
13.
Quantum physics challenges our understanding of the nature of physical reality and of space-time and suggests the necessity of radical revisions of their underlying concepts. Experimental tests of quantum phenomena involving massive macroscopic objects would provide novel insights into these fundamental questions. Making use of the unique environment provided by space, MAQRO aims at investigating this largely unexplored realm of macroscopic quantum physics. MAQRO has originally been proposed as a medium-sized fundamental-science space mission for the 2010 call of Cosmic Vision. MAQRO unites two experiments: DECIDE (DECoherence In Double-Slit Experiments) and CASE (Comparative Acceleration Sensing Experiment). The main scientific objective of MAQRO, which is addressed by the experiment DECIDE, is to test the predictions of quantum theory for quantum superpositions of macroscopic objects containing more than 108 atoms. Under these conditions, deviations due to various suggested alternative models to quantum theory would become visible. These models have been suggested to harmonize the paradoxical quantum phenomena both with the classical macroscopic world and with our notion of Minkowski space-time. The second scientific objective of MAQRO, which is addressed by the experiment CASE, is to demonstrate the performance of a novel type of inertial sensor based on optically trapped microspheres. CASE is a technology demonstrator that shows how the modular design of DECIDE allows to easily incorporate it with other missions that have compatible requirements in terms of spacecraft and orbit. CASE can, at the same time, serve as a test bench for the weak equivalence principle, i.e., the universality of free fall with test-masses differing in their mass by 7 orders of magnitude.  相似文献   
14.
In this article, we estimated the alpha parameter of the Priestley–Taylor model under rain‐fed conditions. This study was conducted in an oat crop, from 7 September to 22 October 2009, in a region of subhumid plains (Tandil, Argentina). An energy balance station was installed within the experimental field to monitor its development. The alpha parameter value obtained was 1.41 ± 0.01, which led to an overestimation of the evapotranspiration of just 2% and a relative error in estimating evapotranspiration of 8%. The results suggest that the alpha parameter obtained is adequate in estimating the evapotranspiration of oat crops or similar crops in subhumid plains of Buenos Aires, Argentina. Copyright © 2012 John Wiley & Sons, Ltd.  相似文献   
15.
This study evaluates the impact of different chemical and meteorological boundary and initial conditions on the state-of-the-art Weather Research and Forecasting (WRF) model with its chemistry extension (WRF-Chem). The evaluation is done for July 2005 with 50 km horizontal resolution. The effect of monthly mean chemical boundary conditions derived from the chemical transport model LMDZ-INCA on WRF-Chem is evaluated against the effect of the preset idealized profiles. Likewise, the impact of different meteorological initial and boundary conditions (GFS and Reanalysis II) on the model is evaluated. Pearson correlation coefficient between these different runs range from 0.96 to 1.00. Exceptions exists for chemical boundary conditions on ozone and for meteorological boundary conditions on PM10, where coefficients of 0.90 were obtained. Best results were achieved with boundary and initial conditions from LMDZ-INCA and GFS. Overall, the European simulations show encouraging results for observed air pollutant, with ozone being the most and PM10 being the least satisfying.  相似文献   
16.
The potential role of microbial consortia on sponge chemistry is well known. However, how environmental factors affect microbial and chemical profiles and how these shifts affect the sponge holobiont are far from being understood. This study experimentally investigated the effect of light on both the concentration of secondary metabolites and the bacterial assemblages of the sponge Aplysina aerophoba. We quantified major brominated alkaloids (BAs) using a high‐performance liquid chromatography system coupled with a UV‐detector and analysed sponge‐associated bacteria using denaturing gradient gel electrophoresis of 16S rRNA gene amplicons. We identified distinct chemical and bacterial profiles between the ectosome and the choanosome of A. aerophoba. The abundance of most secondary metabolites increased regardless of the illumination regime. We found that the probability of occurrence of three microbial phylotypes (operational taxonomic units 84, 86 and 87) was strongly associated with increasing concentrations of three brominated compounds (aerophobin‐1, aplysinamisin‐1 and isofistularin‐3). Although the role of these bacteria remains uninvestigated, these associations between natural products and specific microbial phylotypes outline further hypotheses that will improve our understanding of the organization and functioning of these complex host–symbiont interactions.  相似文献   
17.
The age of three syntectonic unconformities belonging to the Upper Eocene—Middle Oligocene is discussed. The structural characteristics of the conglomerates in the Catalonian south Pyrenees are described with special attention to mechanisms of tectonics and sedimentation and to the lateral relationships between conformity, progressive unconformity (or cumulative wedge system) and angular unconformity. The older unconformities have been tectonically deformed. A new genetic model is proposed to explain offlaponlap mechanisms of each folding phase and the development of angular and progressive unconformities.  相似文献   
18.
19.
Application of Multiple Point Geostatistics to Non-stationary Images   总被引:3,自引:2,他引:3  
Simulation of flow and solute transport through aquifers or oil reservoirs requires a precise representation of subsurface heterogeneity that can be achieved by stochastic simulation approaches. Traditional geostatistical methods based on variograms, such as truncated Gaussian simulation or sequential indicator simulation, may fail to generate the complex, curvilinear, continuous and interconnected facies distributions that are often encountered in real geological media, due to their reliance on two-point statistics. Multiple Point Geostatistics (MPG) overcomes this constraint by using more complex point configurations whose statistics are retrieved from training images. Obtaining representative statistics requires stationary training images, but geological understanding often suggests a priori facies variability patterns. This research aims at extending MPG to non-stationary facies distributions. The proposed method subdivides the training images into different areas. The statistics for each area are stored in separate frequency search trees. Several training images are used to ensure that the obtained statistics are representative. The facies probability distribution for each cell during simulation is calculated by weighting the probabilities from the frequency trees. The method is tested on two different object-based training image sets. Results show that non-stationary training images can be used to generate suitable non-stationary facies distributions.  相似文献   
20.
This paper describes the ground-penetrating radar (GPR) survey performed inside the Cathedral of Valencia, Spain. It is part of historical studies performed in the Cathedral in order to add information to old maps and documents in the Cathedral Archives and also to analyze the extent and importance of potentially destructive moisture areas that were appearing on the floor. The construction of the Cathedral of Valencia occurred in three stages, all of which are well-documented in the Cathedral Archives with detailed drawings, maps, and charts. The radar data were successful in locating crypts, ossuaries, sepulchers, and graves, and the location of ancient walls that existed before the final Cathedral expansion. Three cultural layers corresponding to the three periods of construction were also identified corresponding to the Roman, Arabian and Middle Age Epochs. Measurements of relative sub-floor moisture were obtained by comparing dielectric permittivity changes and radar velocity differences between materials in humid and non-humid areas.  相似文献   
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