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1.
This paper presents the results from extensive parametric dynamic analyses of soil-structure systems that focus on the clear modification (increase or decrease) of the acceleration amplitude at the foundation with respect to the free-field, especially for squatty structures. Properties of the systems are selected such as to cover a wide range of meaningful geometries and materials for engineering practice. The results are presented in terms of weighted modification factors of the maximum foundation acceleration amplitude with reference to the corresponding maximum acceleration amplitude at free-field, for squatty and more slender structures. For the large majority of the studied systems, foundation acceleration decreases from the free-field by 10–15% on average. Nevertheless, acceleration demand at the foundation increases compared to the free-field, for 30% of squatty and for 15% of the more slender structures. Modification of the foundation acceleration amplitude is also correlated with the ratio of the predominant period of the input motion to the flexible-base system period. Finally, the findings of this study are compared with sparse available recorded data from the Seismic Hazard Harmonization in Europe database.  相似文献   
2.
In this article, we use a dynamic spatial microsimulation model of Britain for the analysis of the geographical impact of policies that have been implemented in Britain in the last 10 years. In particular, we show how spatial microsimulation can be used to estimate the geographical and socio-economic impact of the following policy developments: introduction of the minimum wage, winter fuel payments, working families tax credits, and new child and working credits. This analysis is carried out with the use of the SimBritain model , which is a product of a 3-year research project aimed at dynamically simulating urban and regional populations in Britain. SimBritain projections are based on a method that uses small area data from past Censuses of the British population in order to estimate small-area data for 2001, 2011, and 2021.  相似文献   
3.
The present paper examines the importance of integrating geographical effects into the analysis of social networks. Specifically, we study the impacts of spatial distance and territorial borders on information exchange within two European cross-border regions where there is evidence of extensive cross-border political interaction in the domain of public transportation. We use exponential random graph models to review how these spatial factors influence policy interaction. We show how the effect of distance on the exchange of information between organizations is less obvious than it seems at first sight, when we control for endogenous networks effects with which it tends to be confounded. We also explore moderating effects among the spatial factors studied and in particular how the effect of distance affects information exchange by territoriality. While the probability of interaction decreases with distance in the context of domestic ties, distance does not exert the same friction when it comes to cross-border ties. These findings suggest that borders are not necessarily a barrier to interaction and that peripheral actors located in border regions may bridge distance in order to access strategic information they do not have access to within their territorial jurisdiction and is likely concentrated in foreign decision centers.  相似文献   
4.
A method for investigating the forming technique of ancient ceramic vessels is presented. The recording, analysis, and comparison of the vessels' metrical properties by means of computer tomography, three-dimensional laser scanning, and solid-modeling software enables the identification of the applied manufacturing methods. A finite elements method-based simulation of the developed deformations during the vessels' manufacture offers significant insight into the applied shaping procedures. By making possible the exact recording of both the internal and external form of the vessels as well as the simulation of the forming procedure, the method represents a marked improvement to hitherto applied methods based on radiography. The method is applied on two early iron age ceramic jugs (oinochoai) found as offerings in tombs in excavations in Dion, Greece.  相似文献   
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Ancient DNA trapped in the matrices of ceramic transport jars from Mediterranean shipwrecks can reveal the goods traded in the earliest markets. Scholars generally assume that the amphora cargoes of 5th-3rd century B.C. Greek shipwrecks contained wine, or to a much lesser extent olive oil. Remnant DNA inside empty amphoras allows us to test that assumption. We show that short ∼100 nucleotides of ancient DNA can be isolated and analyzed from inside the empty jars from either small amounts of physical scrapings or material captured with non-destructive swabs. Our study material is previously inaccessible Classical/Hellenistic Greek shipwreck amphoras archived at the Ministry of Culture and Tourism Ephorate of Underwater Antiquities in Athens, Greece. Collected DNA samples reveal various combinations of olive, grape, Lamiaceae herbs (mint, rosemary, thyme, oregano, sage), juniper, and terebinth/mastic (genus Pistacia). General DNA targeting analyses also reveal the presence of pine (Pinus), and DNA from Fabaceae (Legume family); Zingiberaceae (Ginger family); and Juglandaceae (Walnut family). Our results demonstrate that amphoras were much more than wine containers. DNA shows that these transport jars contained a wide range of goods, bringing into question long-standing assumptions about amphora use in ancient Greece. Ancient DNA investigations open new research avenues, and will allow accurate reconstruction of ancient diet, medicinal compounds, value-added products, goods brought to market, and food preservation methods.  相似文献   
7.
The changing dynamics of regional and local labor markets during the last decades have led to an increasing labor market segmentation and socioeconomic polarization and to a rise of income inequalities at the regional, urban, and intraurban level. These problems call for effective social and local labor market policies. However, there is also a growing need for methods and techniques capable of efficiently estimating the likely impact of social and economic change at the local level. For example, the common methodologies for estimating the impacts of large firm openings or closures operate at the regional level. The best of these models disaggregate the region to the city (Armstrong 1993; Batey and Madden 1983). This paper demonstrates how spatial microsimulation modeling techniques can be used for local labor market analysis and policy evaluation to assess these impacts (and their multiplier effects) at the local level‐to measure the effects on individuals and their neighborhood services. First, we review these traditional macroscale and mesoscale regional modeling approaches to urban and regional policy analysis and we illustrate their merits and limitations. Then, we examine the potential of spatial microsimulation modeling to create a new framework for the formulation, analysis and evaluation of social and local labor market policies at the individual or household level. Outputs from a local labor market microsimulation model for Leeds are presented. We show how first it is possible to investigate the interdependencies between individual's or households labor market attributes at the microscale and to model their accessibilities to job opportunities in different localities. From this base we show how detailed what‐if microspatial analysis can be performed to estimate the impact of major changes in the local labor market through job losses or gains, including local multiplier effects.  相似文献   
8.
The materiality of world diasporas – in every form, from landmark features to everyday objects – is a relatively modern approach towards studying the diasporas' relationship with both homeland and hostland. Photo narratives and various modes of imaging can be employed to better record, assess and disseminate the narratives of diasporic lifeways in terms of their material culture. This article examines how Greek Orthodox communities have altered Western denomination church buildings in London to serve their spiritual and community needs. The new, amalgamated characteristics are described, while the debate around the role these religious communities should play in the hostland is also discussed.  相似文献   
9.
This paper presents the results of two deep-water archaeological surveys recently conducted in the Aegean Sea, and the advantages of using conventional marine geological techniques in deep-water archaeology. Two Hellenistic wrecks were discovered: one in the Chios-Oinousses strait at 70 m, was a concentration of over 400 amphoras in a 1.5-m-high, high-backscattering, morphological high; the second, west of Kythnos island, at 495 m, consisted of a few amphoras scattered in a 20 × 20-m-wide area. Side-scan sonar was integrated with high-resolution sub-bottom profiling, and the integration of the two data-sets proved to contribute significantly to realistic interpretation of the sonar targets.
© 2007 The Authors  相似文献   
10.
Abstract. Capital subsidies form a major instrument of industrial and regional policy for economically developed countries all over the world, including many European Union and Organisation for Economic Cooperation and Development countries. Research findings have challenged the effectiveness of capital subsidies in assisting productivity growth. This paper treats capital subsidies as a new input and estimates a stochastic production frontier that is not bound by the restrictions imposed by approaches used in previous research works. It is shown that capital subsidies affect total factor productivity growth through technical change and not through scale efficiency, while the disadvantaged location of firms affects technical efficiency.  相似文献   
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