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The success of government efforts to stimulate energy conservation among the public ultimately depends on understanding patterns of energy consumption, perceptions of energy resources, and the adoption of conservation practices. These issues were addressed in a survey of residents of Edmonton and Calgary. Most respondents dismissed the seriousness of energy problems at the provincial level, although energy scarcity at the national and global scales was widely recognized. Conservation behaviour was characterized by a narrow range of adjustments perceived and adopted, attributable largely to patterns of resource perception and socio-economic factors.
La réussite des efforts gouvernementaux pour stimuler les conservations d'energie dépend, en dernière analyse, d' une compréhension des schémas de la consommation énergétique, desperceptions des resourcesénergétiques, et del'adoption d' habitudesconservatrices. On a interrogé les habitants d' Edmonton et de Calgary ace sujet. La plupart des réponses ignorent la gravité des problèmes d'énergie au niveau provincial, quoiqu'elles admettent la précarité des ressources énergétiques à l' échelle nationale et mondiale. L' attitude conservatrice se distingue plus particulikrèment à partir d' ajustements limités reliés géneralement aux schémas de perceptions énergétiques et aux facteurs socio-économiques.  相似文献   
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International economic power (the ability to shape rules of global economic conduct) needs to be understood in terms of the interactions between rule‐makers and rule‐takers in the global economy. Attempts to reshape development paradigms through interventions during financial crisis have been highly significant for the domestic political economy of the developing world. In the 1980s and early 1990s, the primary question was how much countries would liberalize in response to financial crisis. Reactions to the crises of the late 1990s in Asia and Latin America were more varied. This article explores domestic political responses to crises in both regions in the 1980s and late 1990s. It argues that countries are finding it increasingly difficult to trump domestic political pressure for change with arguments about technocratic necessity. Popular pressure is pushing governments into new experiments in economic nationalism, not a radical rejection of global economic integration, but a reshaping of relationships in an attempt to secure national interests and, in some cases, to devote more resources to welfare. Experiments to date are modest, but could presage more significant change in the future.  相似文献   
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One of the steps leading to an assessment of the biological significance of ozone destruction is to determine the biologically effective ultraviolet radiation (UVB) distribution. The objective of this study is to describe and analyze broadband UVB radiation at 24 locations across Canada, during the period from July 1992 through December 1993. This is the first study of broadband UVB measurements involving such a large number of UVB measuring instruments. Quantitative characteristics and statistical analysis of the surface UVB radiation in Canada with respect to ozone amount, as well as cloudiness, are presented. The results indicate higher UVB irradiance in the second half of 1992, compared with the same period in 1993. Among all the locations, Toronto received the greatest dose of UVB radiation in 1993. Excluding Yellowknife, due to its northernmost location (larger zenith angles), Ste-Agathe, Quebec received the smallest dose. Unusually high UVB fluxes were found to occur in March 1993 over eastern Canada. A study of the correlation of UVB radiation with total ozone and cloud opacity was carried out for most of the locations. The results suggest that other meteorological parameters have a significant impact on the ultraviolet levels.  相似文献   
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The Republican and early Imperial monuments of Rome are, for the most part, built of tuffs quarried from at least seven pyroclastic deposits erupted from nearby Monti Sabatini and Alban Hills volcanoes. Remarks by Vitruvius (2.7.1–5), field observations of the monuments, and petrographic and rock testing studies of samples from Roman quarries demonstrate that Roman builders developed a good knowledge of the diverse material properties of the tuffs over centuries of use and exposure. Measurements of compressive strength, specific gravity, water absorption and adsorption of water vapour confirm that the petrographic characteristics of each tuff lithology strongly influence its strength and durability. Early construction utilized weakly durable, soft or vitric tuffs such as Tufo del Palatino or Tufo Giallo della Via Tiberina that are susceptible to decay, as at Temple C (290 bc ) of the Largo Argentina Sacred Area. Late Republican structures, such as the Temple of Portunus (80–90 bc ), employed somewhat durable, vitric–lithic Tufo Lionato reinforced with travertine, a durable limestone quarried near Tivoli. Roman builders selected the material properties of the tuffs to advantage for specific structural elements within large public monuments of the first century bc and the first century ad , as at the tabernae of the Forum of Caesar (46 bc ), where an upper storey of lightweight Tufo Lionato is supported by robust, lithic–crystal Lapis Gabinus pillars and flat arches reinforced with travertine. The tuffs are not very durable building stones; Romans preserved them with protective stucco, and travertine and marble cladding. Their high water intake, coupled with direct exposure to rain, daily fluctuations in relative humidity and urban weathering at present makes them especially vulnerable to decay.  相似文献   
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Previous studies of colourless Romano‐British vessel glasses have suggested that, regardless of vessel type, they show considerable compositional homogeneity. Intriguing differences in variability (as opposed to mean composition) have, however, also emerged. This paper reports on a compositional study of 243 vessels, that is larger and more carefully controlled than in previous studies of this kind. Unexpected compositional differences have been found both between and within the four vessel types studied. We discuss the implications of these results in the context of different models that have been proposed for glass‐making and glass‐working in the Roman world.  相似文献   
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Site F2 in the Timna Valley, Israel, is a small copper smelting site of ‘primitive’ technology, dated by its excavator to the Pottery Neolithic (sixth to fifth millennium bce ). This early date challenges the common view of the beginning of smelting technology in the Levant and has been contested by various scholars since its publication. In this study, we present results of archaeointensity experiments conducted on slag fragments from the site. The slag yielded an excellent ancient geomagnetic value (64.1 ± 1.1 μT) that, when compared to the Levantine master curve, suggests an age not older than the second millennium and most probably between the 13th and 11th centuries bce . In addition to demonstrating the applicability of geomagnetic archaeointensity experiments to independent dating of slag, we discuss the implications of the current results for the socio‐historical picture of the Timna Valley, and in particular for the way in which technological developments were previously modelled in the archaeometallurgical research on the region.  相似文献   
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