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91.
Using Maxwell equations in a background metric discovered by Bonnor, which describes the gravitational field generated by an optimally charged dust ball, we calculate the external radiation field from an electric dipole source at the center the ball. Possible applications to stellar mode 1 s are discussed in the conclusions. 相似文献
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We studied the problematic of uncertainties in the diffuse gamma radiation apparent in stacking analysis of EGRET data at low Galactic latitudes. Subsequently, we co-added maps of counts, exposure and diffuse background, and residuals, in varying numbers for different sub-categories of putatively and known source populations (like PSRs). Finally we tested for gamma-ray excess emission in those maps and attempt to quantify the systematic biases in such approach. Such kind of an analysis will help the classification processes of sources and source populations in the GLAST era. 相似文献
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Ocean and atmosphere changes in the Caribbean Sea during the twenty-first century using CMIP5 models
Ocean Dynamics - Coastal communities around the Caribbean Sea are vulnerable to global warming impacts, partly because of constraints on their adaptive capacity. We use three climate models... 相似文献
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S. Molina Y. Torres B. Benito M. Navarro D. Belizaire 《Bulletin of Earthquake Engineering》2014,12(4):1459-1478
After the 2010 Haiti earthquake, that hits the city of Port-au-Prince, capital city of Haiti, a multidisciplinary working group of specialists (seismologist, geologists, engineers and architects) from different Spanish Universities and also from Haiti, joined effort under the SISMO-HAITI project (financed by the Universidad Politecnica de Madrid), with an objective: Evaluation of seismic hazard and risk in Haiti and its application to the seismic design, urban planning, emergency and resource management. In this paper, as a first step for a structural damage estimation of future earthquakes in the country, a calibration of damage functions has been carried out by means of a two-stage procedure. After compiling a database with observed damage in the city after the earthquake, the exposure model (building stock) has been classified and through an iteratively two-step calibration process, a specific set of damage functions for the country has been proposed. Additionally, Next Generation Attenuation Models (NGA) and \(\hbox {Vs}^{30}\) models have been analysed to choose the most appropriate for the seismic risk estimation in the city. Finally in a next paper, these functions will be used to estimate a seismic risk scenario for a future earthquake. 相似文献
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A currently out-of-service oil distribution and storage station (ODSS) operated in Zacatecas, Mexico, from 1966 to 2000. At present, it is subject to a dismantling process. In 2000, a project, focused mainly on the characterization of the soil contamination in the ODSS, was required, and the convenience of carrying out a health risk assessment (HRA) to determine the required cleaning-up-levels was stated. The study concluded that the ODSS soil was contaminated mainly by gasoline and diesel, showing the presence of methyl-tertbutylether (MTBE), benzene, toluene, ethylbenzene, and xylene (BTEX). Nine of the 16 polycyclic aromatic hydrocarbons (PAHs) identified by the US Environmental Protection Agency (EPA) as priority hydrocarbons were found in the ODSS subsoil. Selected metals were also considered in the evaluation. The geo-accumulation indexes proposed by Muller for Fe, Pb, V, and Zn showed values characteristic of no geo-accumulation. The HRA suggested the reduction of three PAHs, [benzo (a) anthracene, benzo (a) pyrene, and benzo (b) fluoranthene], and vanadium. 相似文献