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Summary. The development of academic géography in Canada was somewhat similar to that in the United States. At the turn of the century géography was probably stronger in the schools in most provinces than it was in most states, but in both countries it seemed to be mainly an uninspired collection of facts about particular places in the world. There was no leadership from Canadian universities to improve the quality of géography nor to change its content or philosophy. As in the United States, but on a smaller scale, géography was known in a few Canadian universities prior to World War I. Its real beginnings, however, were in the latter part of the 1930s.  相似文献   
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In his analysis of the continuing necessity for Britain to retain its nuclear capability, the author argues that the purpose of the British nuclear deterrent is what it has always been—‘to minimize the prospect of the United Kingdom being attacked by mass destruction weapons’. His discussion ranges from the ethical paradox surrounding the possession of nuclear weapons, the central problem of their predictability, the problem of new threat and, in his view, the Utopian non‐proliferation obligations. The possession of the deterrent may be unpleasant, he concludes, but it is necessary, its purpose lying‘not in its actual use but in its nature as the ultimate “stalemate weapon”.’  相似文献   
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Franz Boas organized and shaped American anthropology. No academic discipline of similar scope owed so much to just one person. Within three decades of coming to the United States from Germany he had trained the anthropologists who established its place within the universities and redirected its tone and ethos as well as its theories. The biographies under review help us understand the background, aims, and drive of the man. We shall consider, in particular, the impact he had on the political and ethical tone of the field, the prevalence of women in it, and the importance of his scientific background.  相似文献   
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Satellite imagery from the Heat Capacity Mapping Mission (HCMM) was analysed for Montreal, Quebec. From this imagery, regional metropolitan maps of day/night surface temperatures are produced for an area of approximately 104km2. With the implementation of a surface energy budget model coupled with the satellite data, maps of non-radiative transfers (sensible and latent energy), along with surface properties (moisture availability and thermal inertia), are produced. Regional land surface cover maps are also constructed and then compared with energy exchange patterns. The visual spatial correlation indicates the dominant role that urbanization plays on modifying local climate. In addition, spatial patterns of thermal inertia and moisture availability can now be produced directly from satellite dated rather than being inferred from land-use maps or other planning data. With this development, a data base of urban surface properties can he compiled for climatic impact purposes/i>. Des images satellites provenant du Heat Capacity Mapping Mission (HCMM) furent analysées pour Montréal, Québec. Àl'aidedeces images, des cartes métropolitaines régionales de températures de surface nuit/jour furent produites pour une superficie approximative de 104 km2. A partir d'un modèle de bilan énergitique de surface couplé aux données satellites, des cartes d'échanges d'énergie (énergie latente et sensible) furent produites, tenant compte des propriétés recontrées en surface (hum-idité disponsible et inertie thermique). Des cartes régionales de la couverture terrestre en surface furent également construites puis comparées avec celles des échanges d'énergie. Une corrélation spatiale visuelle indique le rôle dominant que joue l'urbanisation dans la modification des climats locaux. De plus, la configuration spatiale de l'inertie thermique et de I'humidité dkponible peut maintenant être produite directement a partir de données satellites. ll n'est plus nécessaire d'estimer la configuration à partir des cartes d'utilisation du sol ou en employant d'autres procédés semblables. Avec cette méthode, on peut assembler une banque de données des propriétés rencontrées en surface urbaine pour des fins d'analyses d'impacts climatiques.  相似文献   
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