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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.
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   
3.
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   
4.
Optimal Allocation of Land between Productive Use and Recreational Use   总被引:3,自引:0,他引:3  
Abstract This paper is an inquiry into the optimal allocation of time and natural areas to recreational uses, which have the feature of being a pure and continuous public good. We address this issue with a comprehensive approach. A static rational general equilibrium framework is developed in which heterogeneous agents allocate land and time endowments between alternative uses. This modeling has important advantages. First, Pareto‐optimal and voluntary‐contribution equilibrium allocations are obtained in a unified set‐up. Second, the suboptimality result of the decentralized equilibrium, the free‐rider problem on the provision of this nonexcludable public good, and different mechanisms to return the economy to its first‐best are analyzed. Finally, a methodological critique is made of some empirical literature, and it is suggested that our theoretical microeconomic‐based structure seems to be a suitable starting point for empirical research.  相似文献   
5.
Crocker, John Christopher. Vital Souls: Bororo Cosmology, Natural Symbolism, and Shamanism. Tucson: University of Arizona Press, 1985. xiii + 380 pp. including photographs, appendices, bibliography, and index. Foreword by David Maybury‐Lewis. $29.95 cloth.  相似文献   
6.
The analysis of environmental archives from across the world has demonstrated that human perturbation of the geochemical cycles of trace metals and the resultant atmospheric metal contamination date back, at least, several millennia. However, an understanding of the local processes and timing of changes in trace metal deposition is also essential for a proper global interpretation. The Iberian Peninsula was a major mining area since prehistoric times and the analysis of environmental archives provides a good opportunity to improve our understanding of the history of mining and metallurgy in Europe. We present the results from three 14C dated peat cores from the Xistral Mountains (NW Iberia). These records are used to reconstruct past atmospheric deposition of Ni, Zn, As, and Cd. The chronology of the changes in concentrations and metal accumulation rates was found to be concordant in the three bogs, and showed great similarity to total Pb, Hg, and Pb isotope ratios as determined in previous investigations. They present a consistent view of changes in atmospheric pollution and the importance of metals in the development of human societies, especially: i) the first evidence of atmospheric metal pollution 3400 years ago, which is simultaneous with the expansion of the Atlantic Bronze Koine; ii) a pollution event between 2350 and 2150 years ago, associated to the development of so-called Celtic culture (local Late Iron Age); iii) a dramatic increase of metal fluxes in Roman times; iv) a severe and rapid increase in the last 250 years corresponding to the beginning of the industrial revolution in Europe, reflecting the emergence of the new dominant sources of pollution, and v) the increase of long range atmospheric transport of pollutants. Our data suggest that all detected ancient (until ca. 1450 cal BP) periods of enhanced Ni, Zn, As, and Cd accumulation may have had an anthropogenic origin, related to the onset and development of mining and metallurgy.  相似文献   
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Book reviews     
Serviços e Desenvolvimento numa Região em Mudança (Services and Development in a Changing Region). Comissão de Coordenação da Região Centro (Ed.), Coimbra, Comissão de Coordmação da Região Centro, 1993, 443 pp, ISBN 972 659 040 0.

Technology Transfer in Europe. David Charles and Jeremy Howells, London, Belhaven Press, 1992, 256 pp., £35.00, ISBN 1 85293 160 4.

Technology and Economic Development. The Dynamics of Local, Regional and National Change. E. J. Malecki, Harlow, Longman Scientific & Technical; New York, John Wiley, 1991, 495 pp., ISBN 0 470 21723 5.

The Rise of Meso Government in Europe. L. J. Sharpe (Ed.), London, Sage Publications, 1993, 327 pp., £45.00, ISBN 0 8039 8776 5.

British Urban Policy and the Urban Development Corporation. Rob Imrie and Huw Thomas (Eds), London, Paul Chapman, 1993, 216 pp., £15.50 pb, ISBN 1 85396 207 4.  相似文献   

9.
We exploit the GEOSTAT 2011 population grid with a very high 1 km2 resolution to document that Spain presents the lowest density of settlements among European countries. Only a small fraction of the Spanish territory is inhabited, particularly in its southern half, which goes hand in hand with a high degree of population concentration. We uncover through standard regression analysis and spatial regression discontinuity that this anomaly cannot be accounted for by adverse geographic and climatic conditions. The second part of the paper takes a historical perspective on Spain's settlement patterns by showing that the spatial distribution of the population has been very persistent in the last two centuries, and that the abnormally low density of settlements with respect to European neighbors was already visible in the 19th century, which indicates that this phenomenon has not emerged recently as a consequence of the transformations associated with industrialization and tertiarization. Using data on ancient sites, we find that Spain did not feature scarcity of settlements in comparison to other countries in premedieval times, suggesting that its current anomalous settlement pattern has not always existed and is, therefore, not intrinsic to its geography.  相似文献   
10.
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