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1.
A simplified model useful for assessing economic losses due to moderate seismicity events in urban areas has been developed by studying the behavior of buildings before yielding their structural system, allowing for nonuniform stiffness along their height. In particular, buildings are modeled as cantilever shear beams with uniform mass and parabolic reduction of lateral stiffness. This particular stiffness distribution is relevant, as it could be expected to occur in buildings where earthquake action is a critical structural design criterion. The equation of motion governing the dynamic behavior of the proposed model is solved analytically, finding mode shapes in terms of first and second zero-order Legendre functions. The solution is verified by comparing it with results obtained from fine mesh finite element models. The effect of reducing the lateral stiffness is then studied in the first five modes of vibration. Results include modal periods, mode shapes, modal participation factors, and derivatives of mode shapes. In general, it is found that effects of reduction of lateral stiffness in mode shapes are moderate when the lateral stiffness in the free end is smaller than about seventy percent of the lateral stiffness at the fixed end, but become significant for larger reductions. Effects are particularly important for the derivative of the mode shapes, which could play a significant role in estimating interstory drift demands in buildings. Model usefulness is showcased by analyzing a test case where both acceleration and drift demands are assessed by considering uniform beams and beams with parabolic stiffness variation, finding notable improvements by considering the latter.  相似文献   
2.
We examine the relationship between individual commuting behavior and household responsibilities, with a focus on gender differences in that relationship. Using the Dutch Time Use Survey for the years 2000 and 2005, we analyze the relationship between commuting time, home production, and childcare. To deal with reverse causality, we use Propenstity Score Matching techniques to obtain imputed data for individuals. We find that the effect of home production on commuting time for women is more than double that for men, while childcare time has an effect on women's commuting behavior only. Our results shedding light on the Household Responsibility Hypothesis.  相似文献   
3.
Portus Ilicitanus (Picola, Alicante) was the main sea harbour of the Roman Colonia Iulia Ilici Augusta and as such played a crucial role in the supply of fundamental commodities to the Iberian Peninsula. Excavations yielded large quantities of glass in fourth‐ and early fifth‐century contexts. Elemental analysis of 60 samples by laser ablation – inductively coupled plasma – mass spectrometry (LA–ICP–MS) confirmed that the glasses were imported from the Eastern Mediterranean. A majority of the glasses correspond to the HIMTa primary production group, which originates from Egypt. The statistical evaluation of published data of 589 HIMT glasses further revealed differential distribution patterns of the HIMTa and HIMTb subtypes between the Eastern and Western Mediterranean, suggesting chronological trends that are linked to wider geopolitical changes. This demonstrates the need for systematic large‐scale approaches to identify supply patterns and possible factors underlying geographical differences and/or chronological developments.  相似文献   
4.
This article analyses the evolution of Community expenditure, on the basis of the data given in the budget and in the EDF, from the origin of the process in 1957 until the year 2002, the last definitive figures. The technique of principal component factor analysis has been applied to these variables. The basic objective of this study is to detect the interrelationships among the policies of the Union and to effect a classification of them, in order to detect the priorities of the European project and to estimate the dimension of the impact of its policies during the period.  相似文献   
5.
The superposition of anthropogenic remains usually results in archaeological palimpsests, hindering an accurate characterization of the behavior underlying such remains. Aimed at facing this methodological constraint in the study of Palaeolithic contexts, we present a contextual approach to Neanderthal settlement dynamics based on an understanding of lithic assemblage formation processes. We focused on a set of lithic artifacts from the Middle Palaeolithic site of El Salt. With the goal of isolating temporally constrained units of behavioral analysis, we analyzed the spatial distribution of lithic, faunal and combustion remains. Then, the lithic records from each of the resulting units were analyzed from a genetic and technical perspective. This goal was achieved by identifying lithic Raw Material Units (RMU) through observations on reduction processes, refits and their spatial distribution. Our results suggest that El Salt SU X lithic remains represent several diachronic human occupation episodes and different site functions. This study illustrates the benefit of investigating lithic assemblage formation processes to alleviate the palimpsest problem in Palaeolithic contexts.  相似文献   
6.
One of the most interesting sites of the Bronze Age in the central area of the Iberian Peninsula is La Motilla del Azuer (Daimiel, Ciudad Real), dated between 2200 and 1350 bc . The main objective of this study was to investigate interpersonal violence in this site and to report an uncommon case of violent death. No traumatic injury was detected in any child, and men and women significantly differed in the frequency of traumas. More traumatisms were found in men from the earlier stages of occupation, including a young man with at least three blunt force traumas and 26 sharp force traumas. The archaeological findings and trauma patterns in the skeletons of the 65 individuals studied suggest a relatively intense level of exposure to violence for adult men in the earlier stages of occupation of this settlement. Copyright © 2012 John Wiley & Sons, Ltd.  相似文献   
7.
Rock art is one of the most salient features of Neolithic societies in eastern Spain and an explicit form of landscape history. This paper summarizes current debates of Mediterranean rock art chronology and interpretation and explores the contextual differences in two areas of Neolithic settlement with rock art: the Canyoles Valley (Valencia) and the Alcoi Basin (Alicante). Large-scale survey of the Canyoles Valley resulted in a clearer understanding of agricultural land use during the Neolithic that contrasts with evidence from the Alcoi Basin. By analyzing Neolithic rock art in its archaeological context, we discuss the significance and limitations of rock art analysis for understanding and characterizing landscape histories and the transition to agriculture in the region.  相似文献   
8.
This paper presents a methodological tool of statistical correction to assess the capacities of different Roman amphorae, whereby ceramic values are transformed into amounts of transported product. Based on scaled drawings of 1281 Roman amphorae, individual vessels’ capacities have been calculated by applying a CAD software to the inner profiles. Each vessel has been classified according to amphora types and the mean for each type has been calculated to produce a coefficient called Average Capacity (AC). The estimated capacities are highly reliable and show narrow confidence intervals. Therefore, they can be applied immediately as a correction factor in studies of quantification of amphorae aimed at characterizing trading dynamics. As such, we expect that future statistical studies of amphorae will include this statistical coefficient to produce more precise and reliable analysis of assemblages and, consequently, more accurate research on the Roman economy.  相似文献   
9.
Inner Scandinavia is one of the Swedish‐Norwegian INTERREG‐A three sub‐programmes, and has been working in operationalizing cross‐border projects in the border area since 1994. To date, several cross‐border strategies have been implemented, one for each programming period of the INTERREG‐A programme. This article investigates whether these strategies can be regarded as a type of cross‐border planning mechanism in promoting territorial development of the border region. It does so by developing a typology, which captures the essentials of spatial planning, against the background of which the article also analyses Inner Scandinavia governance structures, which involves a whole set of interconnected territorial partnerships between five border counties: Hedmark, Østfold, Akershus (Norway), Värmland and Dalarna (Sweden). Here, the main goal is to see if the Inner Scandinavia governance structure, which was recently altered by the inclusion of the Hedmark–Dalarna cross‐border committee, also known as TRUST, is favourable to the implementation of a genuine and long‐term cross‐border spatial plan, with the ultimate goal of reducing the barrier effect and improving the territorial capital along the cross‐border region. Project dokuments and interviews indicate that the existing cross‐border governance model in Inner Scandinavia, led by the INTERREG‐A Steering Committee, produced substantial progresses in reducing the barrier effect, in all its dimensions, and in supporting the territorial development across the border area. Consequently, the role of other cross‐border governance structures should be confined to promoting the active involvement and mobilization of local and regional actors in the cross‐border cooperation process, and in implementing several cross‐border projects with local/regional significance.  相似文献   
10.
In this article the authors propose a historical analysis of the role of romantic rural imagery in the Spanish (state and peripheral) re-nationalization processes during the Franco dictatorship through the scope of the political and identity meanings assigned to it. Their goal is to better comprehend twentieth-century Spain by examining the use (and abuse) of the rural imaginary by Spanish, Basque and Galician nationalisms, particularly during the time of the totalitarian regime of General Franco, giving special attention to the cultural loans between the ideological (and national) blocs traditionally interpreted as monolithic and irreconcilable: Francoism (1936–1975) and its political opposition.  相似文献   
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