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A study of the synoptic situation which produced the catastrophic floods of November 1988 in Catalonia (in the northeast of the Iberian Peninsula) is presented. Analyses of the vertical structure, potential instability, precipitable water, and instability index are made through the radiosounding data from Palma, Majorca. It is found that the 1988 situation is included in type I intense convective events in Catalonia (classification obtained from all the events since 1950, (Llasat, 1989)). It was characterized by:
(a)  -pattern in the middle and high troposphere, the ridge axis east of Catalonia.
(b)  High pressure over Europe.
(c)  South-easterly winds in the lower troposphere with warm and moist humid air advection and south-westerlies aloft over Catalonia.
(d)  Strong instability (convective and latent).
(e)  Penetration of Atlantic air.
  相似文献   
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Quantification of traffic noise levels in urban areas can be especially useful for environmental and public health policies. A statistical model is proposed here for this quantification in small urban areas. The model is nonlinear and mixed, with two components: a fixed component for traffic noise emission (source effect) and a random component for assessing traffic noise propagation. The proposed model requires only sample data and has been used to estimate basic noise indicators established in European standards. A composite indicator, the Lden indicator, has been computed and used to draw up a noise ranking of urban areas. The proposed approach is applied to the city of Leganés (Spain).  相似文献   
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This work reports the results of an experimental programme aimed at investigating the in-plane behaviour of clay-brick masonry walls externally strengthened by carbon fiber reinforced polymer (CFRP) strips. Particularly, four different geometrical layouts were considered for the CFRP strips, though keeping unchanged the quantity of composites employed in each wall. Firstly, a preliminary experimental work was carried out on samples of the constitutive materials for quantifying their key mechanical properties and evaluating the bond behaviour of FRP strips on the masonry substrates. Then, eleven cyclic shear-compression tests were performed to observe the response of strengthened walls and the influence of the strengthening layouts under investigation. The proposed experimental report is intended as a contribution to the current state of knowledge about the behaviour of FRP-strengthened masonry walls: it is available to assess the accuracy and possibly improve the predictive capacity of design-oriented capacity models. Finally, the comparison of the reported experimental results with the predictions obtained by applying the analytical relationships proposed by a recently issued guideline for FRP strengthening of masonry structures is proposed.  相似文献   
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Prorocentrum lima (Ehrenberg) Dodge has been found for the first time during the summer of 2007 inside Ortona harbor and along the coast of the Abruzzo region, a slightly eutrophic area influenced by runoff from a nearby river. The investigations were conducted in two harbors and at six coastal sampling stations. Samplings were conducted using a phytoplankton net and with a pump. Average P. lima cellular concentrations were 3.2 × 104 cells L−1. Other well-known toxic and potentially toxic phytoplankton species have been considered. The number of toxic cells from net samples were higher than the numbers of toxic cell samples collected without the net. Occurrences of P. lima with abiotic factors revealed that temperature was positively correlated with P. lima abundance (p = 0.01), while salinity was highly negatively correlated with P. lima presence (p = 0.001). The total phytoplankton community was studied.  相似文献   
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