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71.
72.
AAS, FE and OES are each used in the analysis of thirteen samples of fragments of window glasses from three Catalan Gothic churches: Sta. Maria del Mar (Barcelona, Spain), Pedralbes Monastery (Barcelona, Spain) and Girona Cathedral (Spain). Two kinds of stained window glass are found. Special attention is paid to Co/Cu, Co/Ni and Cu/Ni ratios for blue glasses and Mn/Cu and Fe/Cu ratios for red glasses.  相似文献   
73.
Gas liquid chromatography was used to analyse residues adhering to the inside of excavated potsherds from dated South African sites. The results suggested marine animal fat, possibly seal, had been cooked in the vessels. Fat of modern seals was baked and also analysed as a control sample. This gave similar results. The importance of seals in the prehistoric diet of the Southwestern Cape is supported by a large number of seal bones in the associated faunal material.  相似文献   
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75.
This paper describes some developments in the diffusion pattern of Hutterite colonies in North America. Today, there are more than 300 colonies distributed over the four western provinces of Canada and five states of the United States. The spatial behaviour of the three Hutterite clan-groups is compared, and responses by the sects to the repeal of the Alberta Communal Property Act in 1973 are assessed. Finally, changes in the rate of diffusion and the management of colony division are examined.
Cette communication décrit quelques développements dans la diffusion des colonies ďHutterites en Amérique du Nord. Aujourd'hui, il y a plus de 300 colonies dispersées dans les quatre provinces de ľoeust canadien et dans cinq états américains. Nous comparons le comportement spatial des trois groupes, ou clans, principaux ďHutterites et nous évaluons les réactions des sectes àľabrogation de la législation, de 1973, de la loi pourtant sur la possession en commun de propriétés Finalement. on examine le gérance de la division des colonies, et les changements dans leurs taux de diffusion.  相似文献   
76.
Discovery of the uses and later the invention of fire-making are fundamental to humanity. Following reports over the last decade of traces of fire found on Lower Pleistocene archaeological sites in eastern Africa, the dating of the control of fire by hominids has become a controversial issue. In this paper we critically review the contexts and, in the light of a battery of archaeometric techniques, the nature of reported instances of fire from Koobi Fora and Chesowanja in Kenya, and from Gadeb and the Middle Awash in Ethiopia. We conclude with a discussion of the roles fire may have played in the lifeways of early Pleistocene savanna-living hominids.
Résumé La découverte des usages du feu et ensuite de sa préparation est fondamentale pour l'humanité. Suite à des rapports au cours de la dernière décennie signalant des traces de feu relevées dans des sites archéologiques du Pléistocène inférieur dans l'est de l'Afrique, la datation du contrôle du feu par les hominiens est devenu une source de controverse. Dans cet article, nous révisons d'un oeil critique les contextes et la nature des cas de feu signalés à Koobi Fora et à Chesowanja au Kenya, et à Gadeb et dans l'Awash moyen en Éthiopie, à la lumière d'une suite de techniques archéometriques. Suit en conclusion une discussion sur les rôles qu'aurait pu jouer le feu dans les modes de vie des hominiens vivant dans les savannes du Pléistocène inférieur.
  相似文献   
77.
A number of investigations have been undertaken by the New South Wales Water Resources Commission to determine the regional and compound effects of large scale extractive industries on the stability of the Hunter River, New South Wales. Sedimentologic studies of bed material suggest that the Hunter River upstream of Denman has an armoured gravel bed that is immobile during regulated releases from Glenbawn Dam but is disrupted by moderate but less than bankfull flows. Annual bedloadyields have been computed by the bedload rating-flow duration technique for five river gauging stations. Approximate sand and gravel budgets for selected reaches of the Hunter River demonstrate that the present annual extraction rate from temporary sediment storages within the channel greatly exceeds the transport rate upstream of Denman and is approximately equal to the transport rate downstream of Denman. River degradation is imminent if extractive industries continue operating in the channel of the Hunter River  相似文献   
78.
Streamline analyses of mean monthly resultant surface winds over Australia are presented. Mean confluences represent either cyclone trajectories, or modal fronts. These analyses suggest that Australia's annual airstream climate is of two regimes: that of September to March inclusive, and April to August inclusive. The winter half-year is exemplified by a continental airstream source in southern Australia which diverges over virtually the entire continent. It continues into September and October, although dominating only the southern third to half of Australia, and is absent from November to March. During the summer half-year a new pattern emerges, with three maritime air stream sources represented over the continent: first, air from the Southern Ocean penetrates the south coast reaching its furthest northward extension from December to March inclusive; a second source originating over the Pacific Ocean dominates eastern and northern Australia; and a monsoon source originating over the Indian Ocean which flows overland affecting northern Western Australia. Two modal confluences are noted, one over northwestern Australia from November-February separating monsoon flow from that emanating from the east, and another extending from the west central coast east-southeastward to the southeast coast from November-March separating Southern Ocean air from that originating over the Pacific Ocean.  相似文献   
79.
The Multiregional Variable Input-Output (MRVIO) model is introduced to measure the development impact of a transportation system. The MRVIO model is a theoretically flexible, computationally simple, and cost-responsive model. Under the MRVIO model, regional input-output coefficients, trade coefficients, and trade flows become cost responsive and easy to compute. The MRVIO model is employed to measure the development impact of the Arkansas waterway during the period of 1974 to 1978. In the study, the U.S. economy is disaggregated into 3 regions and 35 industrial sectors. The MRVIO model estimates the economic conditions of these 3 regions with and without the waterway in terms of industrial output, income, employment, and trade flows.  相似文献   
80.
Sutton and Lawless review a selection of the prolific literature on the Maghreb's human geography published from the late 1970s onward. The pedigree of the discipline in Maghreb was established by several notable geographers who lived, researched, and wrote there. Augustin Bernard's writings on rural settlement, his atlas, and study of Algeria are still cited. Jean Despois's regional study with Raynal and his work on Tunisia, together with the detailed rural research of Jean Poncet, provides a particularly rich coverage for that country. Jean Dresch's early work on Morocco exemplified an early critique of the contemporaneous uncritical colonial human geography. The Sahara's fascination also inspired pioneering studies by Robert Capot-Rey. The work of these notables and others provided a solid background of geographical literature on the Maghreb to be supplemented, criticized, and challenged by more recent researchers, sometimes pupils of the above individuals, and increasingly North African by birth. The tradition of general texts on the Maghreb has continued, though increasingly with systematic approaches replacing regional appraisals. The geography of the decolonization of the Maghreb by Isnard has been replaced by a study summarizing recent collaborative work by a team of French geographers. The Saharan extensions of the Maghreb states have often been linked in general works, sometimes being juxtaposed against the Maghreb as in the essays offered to Jean Despois. Lawless and Findlay's collaborative study juxtaposes geographical studies of each country's economic development with political scientists' evaluations of their sociopolitical development. This review limits itself largely to geographers and geographical journals, only occasionally including significant works from other subject areas, and to 1977-1978 publications, with a few notable exceptions. The spatial juxtaposition of contrasting approaches to economic development, liberal market economy approaches by Tunisia and Morocco arguably leading to dependency, and centrally-planned strategies by Algeria and Libya resulting in bureaucratic constraints serves to offer the Maghreb as a pertinent case-study region for the applied geographer of developing countries.  相似文献   
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