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72.
73.
Pompeiian-style (hourglass) grain mills are common at many Roman sites within the circum-Mediterranean countries. Three examples are known from Corfe Mullen, London and Hamworthy in southern Britain. Petrographic examination, chemical and microprobe analyses indicate that the Corfe Mullen millstone and the London donkey mill were imported from central France into southern Britain. The Hamworthy mill should be designated a ‘flat donkey mill’, and represents a recent (post-Roman) import from a volcanic source in Sardinia. There is no evidence of importation of Roman donkey mills from Germany or for transportation of such mills (or stylistic derivatives) north of London. 相似文献
74.
This article reports a generalised and systematic approach to the thermoluminescence (TL) dating of samples which suffer from anomalous fading. We hypothesise that the TL signal from each mineral phase is composed of a stable and an unstable portion. The decay of the unstable TL is accelerated thermally, until only stable TL remains. The dating is then carried out on this stable signal. The results, on four known-age, coeval samples, exhibiting gross anomalous fading (25-50% loss over a few days), indicate that many, if not all, samples may successfully be dated with this approach. 相似文献
75.
76.
SHELACH J. SQUIRE 《The Canadian geographer》1988,32(3):237-247
Creative literature colours popular perception of landscape and place. An analysis of English romanticism, Wordsworth's poetry in particular, illustrates how the transformation of an actual landscape into a literary landscape helped change attitudes toward wilderness and natural beauty. The romantic ideology fostered impressions of an idyllic, untamed eden. In response to public fascination with this mythologized and emotional portrait of place, a tourist landscape emerged. Thus even those unfamiliar with romantic literature are encouraged to see particular landscapes from a literary perspective.
Dans la formation d'une perception envers un paysage ou un endroit, un élément important est souvent la littérature imaginaire. Une analyse du romantisme anglais, en particulier la poésie de Wordsworth, démontre comment la transformation d'un paysage actuel sous une forme littéraire contribua fortement à un changement d'attitude envers la nature. Cette idéologie romantique encouragea la notion d'un jardin d'Eden encore sau-vage. la fascination entretenue par ce portrait mythique créa finalement un environnement touristique. Même ceux qui n'ont guère connaissance en littérature romantique ont une vision d'un paysage particulier qui dérive dune perception littéraire. 相似文献
Dans la formation d'une perception envers un paysage ou un endroit, un élément important est souvent la littérature imaginaire. Une analyse du romantisme anglais, en particulier la poésie de Wordsworth, démontre comment la transformation d'un paysage actuel sous une forme littéraire contribua fortement à un changement d'attitude envers la nature. Cette idéologie romantique encouragea la notion d'un jardin d'Eden encore sau-vage. la fascination entretenue par ce portrait mythique créa finalement un environnement touristique. Même ceux qui n'ont guère connaissance en littérature romantique ont une vision d'un paysage particulier qui dérive dune perception littéraire. 相似文献
77.
"An empirical test of the effects of exogenous shocks upon a region's population size is conducted in the framework of an equilibrium locational model. The model emphasizes the separation of endogenous from exogenous factors, a point omitted in most empirical studies of aggregate migration. Exogenous changes are manifested in the local relative cost of living and the local relative unemployment rate. Hypotheses are tested using a national sample of youth, in addition to census, data [for the United States]. Surprisingly, a simple measure of the size of shock to a regional economy has the greatest explanatory power compared to more sophisticated measures based on prior business cycles." 相似文献
78.
ABSTRACT. This paper uses a two-stage hedonic wage approach to derive the benefits from improvement of five cultural amenities. It is argued that the hedonic approach permits valuation of both private and local public aspects of cultural goods since access to the amenity is an essential input in the production of the final service flow. Empirical estimates of willingness to pay suggest price and income elasticities are approximately unity. Lower-bound estimates of marginal benefits for a representative city range from $0.85 million for an additional theater to $57.9 million for an additional zoo facility. 相似文献
79.
Norman R. Cloutier 《Journal of regional science》1988,28(3):415-419
ABSTRACT. The distribution of above-median income groups can be described accurately by OLS regression of the Pareto distribution. The excellent fit of log-linear regression has led some researchers to conclude that extrapolated income measures in the open end of the distribution are reliable. The analysis of income distribution data for metropolitan areas reveals: (1) that OLS tends to consistently overestimate the number of families in the tail, and (2) that the overestimation can have serious implications for hypothesis testing. 相似文献
80.
ABSTRACT The origins and development of the network equilibrium problem are traced and interrelated. Two principal formulations are considered the network equilibrium problem with variable travel demand, and the combined model of trip distribution and traffic assignment. The relation of these models to subsequent developments concerning mode choice, residential location, estimation of origin-destination tables from link flows and stochastic route choice are then reviewed. 相似文献