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Abstract. A hybrid conditional logit choice model is estimated using data on the characteristics and destination of homeowners who engaged in intrametropolitan moves among 17 school districts within the Columbus, Ohio area in 1995. The model is used to test the relative influence of local fiscal and public goods versus household‐level characteristics in determining household location choices across central city and suburban school districts. Results provide evidence of both a “natural evolution” of households to the suburbs, due to job location, residential filtering, and household income and lifecycle effects, and “flight from blight,” due to lower school quality, higher crime levels, and lower average income levels in the city. In comparing the magnitudes of these variables, we find that school quality exerts the strongest influence: a 1‐percent increase in the school quality of the city district increases the probability of choosing a city residence by 3.7 percent. In contrast, the effects of household income and other individual characteristics are relatively modest. The findings provide support for a “flight from blight” suburbanization process that is dominated by differences in neighborhood quality between the city and suburbs. An implication is that investments that promote central city development and reduce suburbanization are justified on efficiency grounds if negative externalities are generated by increased concentration of poverty, crime, and low school quality. 相似文献
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Mauro Cremaschi Savino Di Lernia Elena A. A. Garcea 《African Archaeological Review》1998,15(4):261-286
The Aterian has a huge geographic extension covering all North Africa, although it was not supposed to exist in the mountain ranges of the central Sahara. Its chronological context is not yet definitively determined and it is still difficult to say whether the Aterian tools are technological, typological, functional, or chronological markers. Recent surveys and excavations at Uan Tabu and Uan Afuda, two rock-shelters located in the central Tadrart Acacus, provide the first chronological, environmental and archaeological indications on this Late Pleistocene human occupation in the area. The lack of organic matter led us to perform OSL and TL analyses on sand.
L'Atérien a une énorme extension géographique qui couvre tout le Nord de l'Afrique, tandis qu'on ne pensait pas qu'il existait dans les montagnes du Sahara central. Son contexte culturel n'est pas définitivement déterminé et il est encore difficile de dire si les instruments atériens sont des indicateurs téchnologiques, typologiques, fonctionels ou culturels. Reconnaissances et fouilles récentes à Uan Tabu et Uan Afuda, deux abris situés dans l'Acacous central, fournissent les premières indications sur la chronologie, l'environnement et l'archéologie de l'Atérien dans la région. L'absence de la substance organique, nous a porté à faire des déterminations OSL et TL sur les sables. 相似文献
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This article describes a behavioral model of the Flumen‐Monegros irrigation area (Spain) and presents the results from the model simulation under various policy scenarios. The model combines agronomic, economic and policy information in a framework built using linear programming and crop growth simulation techniques. An important feature of the model is the classification of crop acreage in various types of soils which have different productive potential. The objective function maximizes net margins of crops and includes direct payments of the Common Agricultural Policy (CAP). The crop activities covered in the model are the main crops cultivated in the area (fallow, wheat, barley, corn, sunflower, alfalfa, rice, other crops, and CAP set‐aside). To validate the model, the results on cropland utilization obtained from the model have been compared with actual cropland utilization, concluding that the model closely approximates the actual data. The model is used to characterize the behavior of the irrigation area under three scenarios which reflect likely changes in agricultural and environmental policies: removal of direct payments, increase in water prices, and reduction of fertilizer use. The results show the large impact of these three scenarios on farmers' production decisions: the elimination of direct payment reduces net margin almost by half; prices corresponding to full recovery of water costs reduce significantly the cultivated acreage; and the reduction in fertilizer use causes a fall of 23 percent in net margins. 相似文献
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The Mesolithic period represents a key stage in the human history of Sudan, but its complexity is not yet fully understood.
Since the beginning of prehistoric research in this region, efforts were made to understand Mesolithic site formation processes
and post-depositional disturbances. Responsibility for the destruction of most Mesolithic sites’ deposits rests mainly on
later use of the ancient mound-like settlements as burial places by Meroitic and post-Meroitic people. Excavations at several
sites in the El Salha and Al Khiday areas (White Nile, south of Omdurman) have provided recent progress in our knowledge of
Mesolithic living structures in their palaeoenvironmental contexts. Detailed stratigraphic and geoarchaeological investigations
enabled us to distinguish, within the sequences identified at excavated mounds, the existence of basal archaeological strata
still in situ that had remained unaffected by subsequent anthropogenic disturbances and to understand the functional aspects
of several archaeological features associated with Mesolithic living floors. This offers the opportunity to reassess the Mesolithic
cultural sequence in the region and reconsider some statements on the economic and social aspects of Mesolithic life and landscape
exploitation strategies. 相似文献
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Enclosure walls from late IV to II millennium are an important archeological feature in southeast Iberia and south Portugal. These enclosures were considered to be fortified settlements but have more recently been interpreted as the result of general processes of social complexity, symbolism, monumentality, interaction, and space demarcation, among others. Metric and geometric studies associated with architectural concepts are very important tools to analyze prehistoric communities and bring their own perspective to bear. The planning of monuments or even whole settlements includes a more general perception of space, determined by mythology, topography, taking of place, and social hierarchy, among others. 相似文献
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Multiple paths of development: knowledge bases and institutional characteristics of the Swedish food sector 总被引:1,自引:0,他引:1
The aim of this paper is to explore the relation between the critical knowledge base of firms and how firms respond to incentives embedded in the institutional framework surrounding them. The analysis gives us a better understanding of the complex development of the food sector in Southern Sweden in the past decades. Theoretically, the paper combines concepts of path dependency and knowledge bases, and applies this framework to a set of development trajectories of firms in the Scanian food sector. Three development paths are identified—path extension, path renewal and new path creation. Findings illustrate that these are rooted in different knowledge base combinations of firms, which make them respond differently to similar place- and sector-specific institutional conditions. 相似文献
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Elena Maragoudaki Panayiotis K. Kavvouras 《Archaeological and Anthropological Sciences》2012,4(3):199-208
The present study aims to answer questions of utility and efficiency, on the basis of archaeological evidence, of the nominated Mycenaean shipwright tool kit through experimental methods. The target set was established through the recording of archaeological data, examination of the available findings, classification of the finds, gathering of the relevant sources (literature, iconography, archeological parallels and preserved traces), reconstruction of the findings (casting, elaboration of the metallic parts and reconstruction of the hafts), usage of the reconstructed tools and the evaluation of them qualitatively, quantitatively and ergonomically via the reconstruction of a segment of the Uluburun shipwreck hull. Knowledge of tool production of the Late Bronze Age has been furthered. Questions on the casting of the metal parts of tools and the elaboration of their different parts have been answered. The reconstructed tools appear suitable for use in pegged mortise-and-tenon joinery in shipbuilding by skilled woodworkers. Moreover, the reconstructed tools proved to be user friendly. Experimental methods proved useful in the allocation of efficient criteria for the use-based classification of tools. Functional differences between the tools were shown, and questions on utility were answered. The Late Bronze Age shipwright, as master of his craft and tool use, could make new tools or adjust them to the demands of a particular job, as well as to his own body build. The range of tools used for shipbuilding in the Late Bronze period is comparable to those used today. 相似文献