ABSTRACT:The historical daily precipitation observations for the Netherlands were fully digitized recently. The homogeneity of the precipitation series was tested by pairwise comparisons of the monthly totals using an algorithm of Menne and Williams. Forty percent of the precipitation series was indicated as inhomogeneous if the algorithm was applied to the untransformed monthly totals. The use of a square-root transformation to reduce the skewness was only successful in an application to the data for the 1951-2009 period. Changes in the annual precipitation amounts, the precipitation amounts in the winter and summer halves of the year, the number of days per year with a precipitation amount greater than 20 or 30 mm, and the 5-d annual maximum precipitation amount were determined both for the period 1951-2009 using the data from 240 stations and the period 1910-2009 with the data from 102 stations. Significant increases were found for all six indices. The centennial increases in mean annual, winter and summer precipitation are 25, 35, and 16%, respectively. The exceedance frequency of the 30 mm threshold almost doubled during the 1910-2009 period. Much attention is given to the field significance of trends, the statistical significance of regional differences in trends and nonlinearity of trends. In contrast to the increase in mean winter precipitation, which is statistically significant for the majority of the stations, the increase in mean summer precipitation is mainly restricted to coastal regions. The mean summer precipitation and the exceedance frequencies of the 20 and 30 mm thresholds show a relatively strong increase from the beginning of the 1980s.

The study analyses the data related to a database of 7597 private Reinforced Concrete buildings located in the city and the province of L’Aquila surveyed after the 2009 earthquake. Survey data were collected by the Italian Department of Civil Protection during post-earthquake usability inspections including information on building characteristics, level and extent of damage to structural and non-structural components. For each building, the Peak Ground Acceleration demand has been determined according to data available from the ShakeMap of the event and the georeferenced building location. The analysis of data highlights the key role played by the damage to non-structural components—namely, infills and partitions. Damage Grades according to the European Macroseismic Scale EMS-98 have been derived from damage data to single building components. Two building classes have been defined in the study in order to investigate the influence of number of storeys of buildings on the observed damage. Damage Probability Matrices have been derived for the assumed building classes and bins of Peak Ground Acceleration, and observed trends are analyzed. Different methodologies for estimating fragility functions from data on Damage Grades and Peak Ground Acceleration demand are illustrated, discussed and applied to the database, leading to the derivation of EMS-98-based fragility curves for the defined building classes. Finally, the proposed fragility curves are compared with main empirical fragility curves for RC buildings from literature studies

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In this paper, considering time-averaged velocity as a random variable, two-dimensional (2D) velocity distributions in open-channel flow have been derived based on the Shannon entropy concept and the principle of maximum entropy. The velocity distributions so derived have limited practical use, since they contain too many parameters that need to be experimentally calibrated and hence are not convenient to apply. This work develops a new entropy-based approach for deriving a 2D velocity distribution in open-channel flow, thereby investigating a rectangular geometric domain. The derived distribution is parsimonious, and the values determined using the proposed distribution are found to be in good agreement with the experimentally-measured velocity values.

In the immediate post-earthquake, the safety conditions of buildings are commonly evaluated by field visual inspections. Then, a second phase involves the design of repair interventions and the relevant funding requests to the government or to insurance companies. The paper discusses the data related to the 2009 L’Aquila earthquake, focusing on the empirical damage and relevant Actual Repair Costs (ARC) of damaged residential buildings derived from requests for funding presented by practitioners engaged by owners in the reconstruction process. In particular, the data collected from a set of 2500 residential Reinforced Concrete (RC) and masonry buildings are presented focussing on the construction age, number of storeys, damage extent on structural components and ARC. A damage index for each building component has been computed according to data collected by field inspections and the relationship between damage index and different classes of buildings is herein outlined. Then, a correlation between the empirical damage and ARC is determined by means of a regression analysis. The proposed relationship between empirical damage and ARC may drive decision makers, in the immediate post-earthquake, to make preliminary estimates of the repair costs, only based on quick surveys on residential buildings. The relationship may also be used as a tool to figure out repair costs based on damage scenarios