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A. GIUMLIA‐MAIR 《Archaeometry》2005,47(2):275-292
In recent years, several groups of archaeological metal finds from the areas around the southeastern Alps, dated between Bronze Age and Roman times, have been scientifically analysed (by ICP, AAS and/or XRF) within the framework of different projects. The data now available give a fairly good general picture of the evolution and development of metallurgy in this area and seem to indicate that the region played an important role in the exchange of objects and raw materials over many centuries. The significance of some of the metal finds, which are particularly relevant for this research, is discussed. 相似文献
174.
Since little is known about the cuerda seca technique, our aim has been to complete an initial analysis of 11th‐century cuerda seca by studying fragments from the 10th century (Pechina, Almería) and the 12th century (Mértola and Almería), so as to establish the diachronic evolution of this technique. Characteristics specific to cuerda seca ceramic glazes were investigated using scanning electron microscopy (SEM) and quantitative chemical analysis with energy‐dispersive X‐ray spectrometry (EDX). The chemical compositions of the different‐coloured glazes (green, black, yellow and white) have given us valuable indications about the evolution of the technique. The opacification mode and the firing process were also investigated. With the help of cathodoluminescence (CL) and the study of modern ‘cuerda seca’ glazed ceramics, new hypotheses regarding the number of firing stages, taking into account glaze and paste transformations and their interactions, are put forward. 相似文献
175.
Modeling Regional Economic Resilience to Disasters: A Computable General Equilibrium Analysis of Water Service Disruptions* 总被引:5,自引:0,他引:5
Abstract. Recent natural and manmade disasters have had significant regional economic impacts. These effects have been muted, however, by the resilience of individual businesses and of regional markets, which refers to the inherent ability and adaptive responses that enable firms and regions to avoid potential losses. Computable general equilibrium (CGE) analysis is a promising approach to disaster impact analysis because it is able to model the behavioral response to input shortages and changing market conditions. However, without further refinement, CGE models, as well as nearly all other economic models, reflect only “business‐as‐usual” conditions, when they are based on historical data. This paper advances the CGE analysis of major supply disruptions of critical inputs by: specifying operational definitions of individual business and regional macroeconomic resilience, linking production function parameters to various types of producer adaptations in emergencies, developing algorithms for recalibrating production functions to empirical or simulation data, and decomposing partial and general equilibrium responses. We illustrate some of these contributions in a case study of the sectoral and regional economic impacts of a disruption to the Portland Metropolitan Water System in the aftermath of a major earthquake. 相似文献
176.
Emili Tortosa‐Ausina Francisco Prez Matilde Mas Francisco J. Goerlich 《Journal of regional science》2005,45(1):147-182
Abstract. Economic performance in Spanish provinces has led to a considerable improvement in standard of living of their populations. Intense capital accumulation since the 1950s played a key roll in this process. Provincial inequalities may increase or decrease as a result of this growth pattern. This study analyzes the evolution of the disparities by means of distribution dynamics techniques. It explicitly considers economic size of each province and whether spatial spillovers exist. Results indicate that the convergence process has been especially intense for labor productivity, total factor productivity, and capital intensity, while for per capita income the patterns of convergence are less marked. When we weight our analysis according to economic size of each province, our conclusions do not hold. However, when we take geographic location into account, we find support for our conclusions. 相似文献
177.
A. CRISTINA DE LA VEGA‐LEINERT SUSANNE STOLL‐KLEEMANN TIM O'RIORDAN 《Geographical Research》2009,47(4):351-361
This paper makes the case for advancing sustainability science partnerships (SSPs) both within universities and through innovative means of integrating universities with external public‐private and civil sectors. It links the basic principles of sustainable development with an emerging science of cooperative learning that connects researchers to a wide range of partners. SSPs are specifically designed to be transformational through becoming active agents for societal change. Universities play a special role here because they can act both as communication networks and as laboratories for developing the capability to design and manage SSPs in the creative transition to sustainability. It is gratifying to note that these ideas are beginning to emerge in a number of universities, with European examples being highlighted in this paper. Further steps towards introducing full‐blooded SSPs across the university spectrum are suggested. 相似文献
178.
U‐series dating was used to determine the growth rate of a feldspar‐to‐clay weathering rind in a mid‐Holocene Cascade–Olcott tradition andesite core, and luminescence dating (last exposure to sunlight) was used to date fine‐grained feldspars scraped from the surfaces of similar buried artefacts from a 14C‐sediment‐dated archaeological site (45KI464) on the wet western slope of the Cascade Mountains of Washington. For U‐series dating, we measured 226Ra excess (226Ra excess =226Ra –230Th) in five stratigraphic depth controlled rind scrapings. 238U, 232Th and 230Th were counted by alpha spectrometry, and 226Ra and 210Pb were counted by gamma spectrometry on each sub‐sample. 相似文献
179.
Fragments of late medieval highly decorated Falke‐group stoneware have been found in excavations all over central and northern Europe. The distribution of the finds points to an origin in Saxony, but the exact centre of production is still unknown. Therefore, a set of samples has been analysed with Neutron Activation and the data compared with Saxon reference groups. The results point to production in a single workshop. The data can be clearly distinguished from all reference groups in our databank. However, the most similar group is that of Zittau, Saxony. Also, one sherd, which is typologically very similar to the Falke group, and which was made in Zittau, suggests that production was based there. 相似文献
180.
Marie‐Laurence De Keersmaecker Pierre Frankhauser Isabelle Thomas 《Geographical analysis》2003,35(4):310-328
The objective of this paper is to compare fractal‐based parameters calculated by different fractal methods for urban built‐up areas and to link the observed spatial variations to variables commonly used in urban geography, urban economics, or land‐use planning. Computations are performed on Brussels, Belgium. Two fractal methods (correlation and dilation) are systematically applied for evaluating the fractal dimension of built‐up surfaces; correlation is used to evaluate the fractal dimension of the borders (lines). Analyses show that while fractal dimension is ideal for distinguishing the morphology of Brussels, each estimation technique leads to slightly different results. Interesting associations are to be found between the fractal dimensions and rent, distance, income, and planning rules. Despite its limitations, fractal analysis seems to be a promising tool for describing the morphology of the city and for simulating its genesis and planning. The model is robust: it replicates the urban spatial regularities and patterns, and could hence fruitfully be integrated into intra‐urban simulation processes. 相似文献