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51.
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José I. Castillo-Manzano Mercedes Castro-Nuño Fernando González Laxe Lourdes López-Valpuesta M. Teresa Arévalo-Quijada 《Marine Policy》2009
Spanish Port Authorities currently face a wide range of complexities in their decision-making processes, as they have to satisfy several port management objectives that may conflict with one another. This paper examines these circumstances by using decision theory methodology with multiple objectives, which, through the Promethee method, makes the design of an index possible. This index combines different decision factors that shape the competitiveness of a port to rank the Spanish Port Authorities. This ranking serves as an alternative to the traditional ranking system by easily providing more information about port traffic. 相似文献
53.
Rosa de la Torre Leopoldo G. Sancho Asunción de los Ríos Karen Olsson-Francis Petra Rettberg Jean-Pierre P. de Vera Jesus Martinez Frías Maria Mercedes Lucas Ana Pintado 《Icarus》2010,208(2):735-292
In the space experiments Lithopanspermia, experimental support was provided to the likelihood of the lithopanspermia concept that considers a viable transport of microorganisms between the terrestrial planets by means of meteorites. The rock colonising lichens Rhizocarpon geographicum and Xanthoria elegans, the vagrant lichen Aspicilia fruticulosa, and endolithic and endoevaporitic communities of cyanobacteria and bacteria with their natural rock substrate were exposed to space for 10 days onboard the Biopan facility of the European Space Agency (ESA). Biopan was closed during launch and re-entry. In addition, in the Stone facility, one sample of R. geographicum on its natural granitic substrate was attached at the outer surface of the re-entry capsule close to the stagnation point, only protected by a thin cover of glass textolite. Post-flight analysis, which included determination of the photosynthetic activity, LIVE/DEAD staining, and germination capacity of the ascospores, demonstrated that all three lichen were quite resistant to outer space conditions, which include the full spectrum of solar extraterrestrial electromagnetic radiation or selected wavelength ranges. This high resistance of the lichens to space appears to be due to their symbiotic nature and protection by their upper pigmented layer, the cortex. In contrast, the rock- or halite-inhabiting bacteria were severely damaged by the same exposure. After atmospheric re-entry, the granite of the Stone sample was transformed into a glassy, nearly homogenous material, with several friction striae. None of the lichen cells survived this re-entry process. The data suggest that lichens are suitable candidates for testing the concept of lithopanspermia, because they are extremely resistant to the harsh environment of outer space. The more critical event is the atmospheric re-entry after being captured by a planet. Experiments simulating the re-entry process of a microbe-carrying meteoroid did not show any survivors. 相似文献
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Elena Mercedes Perez-Monserrat Monica Alvarez de Buergo Miguel Gomez-Heras Maria Jose Varas Muriel Rafael Fort Gonzalez 《Environmental Earth Sciences》2013,69(4):1071-1084
The stone traditionally used to build cities contributes to their personality and attests to the geological substrate on which they stand. While stone decay in the built heritage can be attributed to a number of causes, anthropic activity has a particularly significant impact. The geomonumental routes project is one of the initiatives proposed in recent years for urban routes that convey geological fundamentals by observing the rocks present in heritage structures. Its innovative approach addresses traditional stone properties, original quarrying sites and mechanisms of decay. Madrid’s Royal Palace is a fine example of the use of traditional building stone in the centre of the Iberian Peninsula. In the geomonumental route proposed, the building doubles as an in situ laboratory that affords an overview of the main petrological properties of the two traditional stones most commonly used in the city’s built heritage, the forms of decay they are subject and the factors underlying such alterations. This route constitutes a tool for showing the main petrological features and decay forms in traditional building stones found in urban heritage façades, with a special focus on anthropic impact, primarily air pollution and the use of conservation treatments that time has proven to be unsuitable. 相似文献
57.
Solla Mercedes Buceta-Bruneti Gonzalo Elseicy Ahmed Nieto-Muñiz Breogán 《Surveys in Geophysics》2022,43(5):1587-1606
Surveys in Geophysics - This paper deals with the application of the Ground Penetrating Radar (GPR) method in the assessment of stone monuments. Compilation of published works and a discussion of... 相似文献
58.
Mercedes García-Antón Fátima Franco-Múgica Carlos Morla-Juaristi Javier Maldonado-Ruiz 《Quaternary Science Reviews》2011,30(5-6):757-768
The aim of this paper is to reconstruct the variation in the vegetation during the Holocene on the Northern Meseta through pollen analysis in order to determine the roles played by Pinus and Quercus in the vegetation dynamics. A new pollen sequence, Camporredondo, in the centre of the Duero River basin, Northern Meseta, Spain, is presented. It covers the period from ca 11,250 to 1630 cal yr BP. The Camporredondo sequence suggests that a forested landscape existed from the start of the Holocene with values of approximately 90% of arboreal pollen mainly derived from pine forests in the surroundings. Shortly after 8600 cal yr BP pine forests continued to dominate but the landscape became more open while stands of deciduous and evergreen Quercus developed. Around 4500 years ago, coinciding with the start of a period of less rainfall, the lacustrine areas in these territories began to silt up, favouring hydrophytic taxa such as Salix or Cyperaceae. A comparison with other Holocene pollen sequences from the central-eastern part of the Northern Meseta confirms the presence of pine forests in the whole region since the early Holocene. We discuss the variations of the general vegetation pattern in terms of the local or regional conditions at each site. Throughout the Holocene, Pinus forests dominated at least in the eastern half of the Duero River basin. The typical Holocene substitution of conifers by broadleaf species as recorded in other parts of the Iberian Peninsula and Europe, never takes place in the study area. The results of the present study suggest that the current view of the potential vegetation in the Spanish Northern Meseta should be reviewed. 相似文献
59.
Simple and highly accurate formulas for the computation of Transverse Mercator coordinates from longitude and isometric latitude 总被引:2,自引:0,他引:2
A conformal approximation to the Transverse Mercator (TM) map projection, global in longitude λ and isometric latitude q, is constructed. New formulas for the point scale factor and grid convergence are also shown. Assuming that the true values
of the TM coordinates are given by conveniently truncated Gauss–Krüger series expansions, we use the maximum norm of the absolute
error to measure globally the accuracy of the approximation. For a Universal Transverse Mercator (UTM) zone the accuracy equals
0.21 mm, whereas for the region of the ellipsoid bounded by the meridians ±20° the accuracy is equal to 0.3 mm. Our approach
is based on a four-term perturbation series approximation to the radius r(q) of the parallel q, with a maximum absolute deviation of 0.43 mm. The small parameter of the power series expansion is the square of the eccentricity
of the ellipsoid. This closed approximation to r(q) is obtained by solving a regularly perturbed Cauchy problem with the Poincaré method of the small parameter.
Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users. 相似文献
60.
The present study describes the temporal variability of the water fCO2 as well as the different driving forces controlling this variability, on time scales from daily to seasonal, in the Rio San Pedro, a tidal creek located in a salt marsh area in the Bay of Cadiz (SW Iberian Peninsula). This shallow tidal creek system is affected by effluents of organic matter and nutrients from the surrounding marine fish farms. Continuous pCO2, salinity and temperature were recorded for four periods of approximately one month, between February and September in 2004.Major processes controlling the CO2 variability are related to three different time scales. Daily variations in fCO2 are controlled by tidal advection and mixing of the water from within the creek and the seawater that enters from the Bay of Cadiz. Significant cyclical variations of the fCO2 have been observed with the maximum values occurring at low tide. On a fortnightly time scale, the amplitude of the daily variability of fCO2 is modulated by the variations in the residence time of the water within the creek, which are related to the spring–neap tide sequence.On a third time scale, high seasonal variability is observed for the temperature, salinity and fCO2. Maximum and minimum values for fCO2 were 380 µatm and 3760 µatm for February and July respectively. Data suggest that seasonal variability is related to the seasonal variability in discharges from the fish farm and to the increase with temperature of organic matter respiratory processes in the tidal creek. The fCO2 values observed are in the same range as several highly polluted European estuaries or waters surrounding mangrove forests. From the air–water CO2 flux computed, it can be concluded that the Rio San Pedro acts as a source of CO2 to the atmosphere throughout the year, with the summer accounting for the higher average monthly flux. 相似文献