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Federico-Vladimir Gutierrez-Corea Miguel-Angel Manso-Callejo Antonio Vázquez-Hoehne 《Earth Science Informatics》2013,6(3):145-163
The aims of this research are: (i) to check availability of weather observations from automated stations in Spain, (ii) to qualitatively and quantitatively describe the networks identified, (iii) to analyze availability of the observations gathered for 3 different networks [two government (GOV): AEMET with national coverage and CASTILLA Y LEÓN on a regional level; and METEOCLIMATIC, a network of volunteer weather observation (VWO) stations on a national level], and (iv) to undertake a spatial redundancy and lacunarity analysis of them. The results reveal: the existence of heterogeneous VWO networks complementing the GOV, differences within and among networks as far as data acquisition frequency, varying delays in their publication, and semantic differences in the observations made. An inventory was made of 24 networks (16 GOV and 8 VWO) with 3,908 stations deployed in Spain. An analysis of observations from 3 networks reveals that 88 % of the stations in the volunteer network record more than two observations per hour. 56 % of the AEMET stations report more than 48 observations every day, 31 % report between 25 and 48 observations a day. Conversely, the CASTILLA Y LEÓN network records data every half hour. The redundancy analysis reveals a 3,429-drop in the number of unduplicated stations. Following the lacunarity analysis of spatial distribution, it is possible to conclude that 60.72 % of the cells do not contain any stations. 相似文献
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Tobias Leismann Miguel-Angel Aloy Ewald Müller 《Astrophysics and Space Science》2004,293(1-2):157-163
In a series of time dependent numerical simulations we have performed a parameter study of magnetised relativistic jets. We have found that the impact of the magnetic field on the morphology of a jet depends strongly on the configuration of the field. 相似文献
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Miguel-Angel Bernabé-Poveda 《International Journal of Digital Earth》2015,8(8):640-655
The terrain reversal effect is a perceptual phenomenon which causes an illusion in various 3D geographic visualizations where landforms appear inverted, e.g. we perceive valleys as ridges and vice versa. Given that such displays are important for spatio-visual analysis, this illusion can lead to critical mistakes in interpreting the terrain. However, it is currently undocumented how commonly this effect is experienced. In this paper, we study the prevalence of the terrain reversal effect in satellite imagery through a two-stage online user experiment. The experiment was conducted with the participation of a diverse and relatively large population (n = 535). Participants were asked to identify landforms (valley or ridge?) or judge a 3D spatial relationship (is A higher than B?). When the images were rotated by 180°, the results were reversed. In a control task with ‘illusion-free’ original images, people were successful in identifying landforms, yet a very strong illusion occurred when these images were rotated 180°. Our findings demonstrate that the illusion is acutely present; thus, we need a better understanding of the problem and its solutions. Additionally, the results caution us that in an interactive environment where people can rotate the display, we might be introducing a severe perceptual problem. 相似文献
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Javier Romero Gérard Pergent Christine Pergent-Martini Miguel-Angel Mateo Cécile Regnier 《Marine Ecology》1992,13(1):69-83
Abstract. The ecosystem associated to the Mediterranean seagrass Posidonia oceanica shows a clear distinction in two subcompartments regarding turnover time: aboveground and belowground. Aboveground parts (leaves) are highly dynamic, and most of the leaf material is decomposed or exported in less than one year, representing a net loss of nutrients. In contrast, belowground biomass (roots and rhizomes) has a turnover time of the order of centuries, with a consequent accumulation of organic matter in the sediment. The accumulation rates for the single elements rank in the order C > N > P. This ecosystem may be considered as a sink for biogenic elements. 相似文献
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Anguita Francisco Anguita Jorge Castilla Gabriel De La Casa Miguel-Angel Domínguez José-María Herrera Raquel Llanes Pilar López Mónica Martínez Vicente 《Earth, Moon, and Planets》1997,77(1):55-72
A regional geologic study of Arabia Terra, a densely cratered area of Mars northern hemisphere, has revealed the individuality
of this province. This is best expressed by an equatorial belt with a crater age distinctly younger as compared to the northern
part of Arabia Terra and to Noachis Terra to the south. We interpret this as an incipient back-arc system provoked by the
subduction of Mars lowlands under Arabia Terra during Noachian times. The regional fracture patterns are also best explained
in this manner, making it unnecessary to appeal to a rotational instability of the planet, which is not supported by the palaeoclimatic
indicators in the area. This model could be the first regional-scale confirmation of Sleep's (1994) hypothesis of a limited
plate consumption as an explanation of the martian dichotomy.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
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A spatio-temporal hierarchical Markov switching model for the early detection of influenza outbreaks
Amor&#;s Rub&#;n Conesa David L&#;pez-Qu&#;lez Antonio Martinez-Beneito Miguel-Angel 《Stochastic Environmental Research and Risk Assessment (SERRA)》2020,34(2):275-292
Stochastic Environmental Research and Risk Assessment - Rapidly detecting the beginning of influenza outbreaks helps health authorities to reduce their impact. Accounting for the spatial... 相似文献
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