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Nearshore water circulation and bar patterns at Coledale, New South Wales, were surveyed daily over thirty-six consecutive days, from 3 November to 8 December 1978, to identify sequences of changes that might occur in response to spring-to-spring tide cycles of fourteen days, changing barometric and wind conditions associated with the passage of anticyclonic weather systems across the coast, and day to day variation in the nearshore wave regime. During the survey the bar patterns tended to vary from transverse bars, through a composite arrangement incorporating longshore and transverse bars, to a longshore bar pattern as the tide changed from its spring to neap tide phase. However, this sequence was too brief to unequivocally establish variations in nearshore bar pattern that might be attributed to the fourteen day, spring-to-spring tide cycle. Nevertheless, morphologic changes occurring in response to wave regime fluctuation at Coledale were broadly in accord with studies from elsewhere by Dolan et al. (1979, 1982), and Clarke and Eliot (1982, 1983) in that bars and rips were systematically distributed along the beach. At Coledale, bars tended to relocate approximately 0.4 and 0.75 of the distance along the beach from its southern end. The preferred bar spacing closely matches hypothetical standing waves trapped between the headlands of the Coledale embayment. Temporally, the nearshore morphology is highly responsive to wave regime changes such that, as primary breaker heights decrease and remain below Hmax=1.0m, the bar pattern changes from longshore through mixed to transverse bar patterns within three to five days. On one occasion the bar pattern switched from a longshore to a transverse bar pattern within twenty-four hours.  相似文献   
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European security depends on the effective collaboration of the five major powers; it will be undermined by the extension of NATO, a policy driven by US domestic politics. The main threats to security are: the breakdown of political and economic stability; unintended nuclear proliferation and/or failure of the START process; Russia's evolving political and territorial aspirations. All three will remain marginal as long as Russia is constructively engaged with the West. NATO expansion threatens that engagement. It is seen by all strands of Russian opinion as violating the bargain struck in 1990 and will likely lead to the withdrawal of cooperation. Invitations to Poland, Hungary and the Czech Republic cannot be rescinded, but the consequences can be mitigated by refraining from integrating them into NATO's military structure, by ceasing to insist that NATO membership is open to all, and by perpetuating the de facto nuclear‐weapons‐free zone that presently exists in Central and Eastern Europe. Britain's stance could be pivotal.  相似文献   
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The Fourth Assessment Report of the Intergovernmental Panel on Climate Change (IPCC) raised public awareness of the need to consider climate change in coastal management and gained international recognition when it received a joint award of a Nobel Peace Prize in 2007. The raised awareness of climate change surrounding the work of the IPCC was in large part responsible for the focus of the recent Australian national inquiry into coastal management in the context of potential climate change impacts on the coast, conducted by the House of Representatives Standing Committee on Climate Change, Water, Environment and the Arts. In the same year the then Minister of Climate Change, Senator Penny Wong, and the Department of Climate Change released a major government report Climate Change Risks to Australia's Coast and set up a national Coasts and Climate Change Council to provide advice to the government. This paper provides a review and analysis of the extent to which climate change issues, within the context of the broader global change debate, have influenced Australian coastal management through its legislation, policies and practice. In particular, the paper focuses on the impact of recent national reports and state government legislative and policy changes and draws conclusions on future directions for Australian coastal management.  相似文献   
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This paper traces the introduction into Upper Canada of elements of the New South Wales System. The most significant development was the institution in 1825 of a sales policy, at the instigation of the imperial government. Using data drawn from pro / co 47, stepwise multiple regression analysis is used to describe the 'upset' price of land in relation to six independent variables. Population density, the number of mills, and distance to road are identified as the most significant variables in the minds of those who set land prices.
Dans cet article, on fait le suivi de certains éléments du système 'New South Wales' à partir de leur introduction dans le Haut-Canada. Leplus important fait à signaler est l'institution en 1825 d'une politique des ventes par le gouvernement impérial. À l'aide de données tirées du pro/co 47, une analyse de régression multiple pas-à-pas ('step-wise') est utilisée afin de caractériser la mise à prix des terres par rapport à six variables indépendantes. l'analyse démontre que la densité de population, le nombre de moulins et la proximité de la route étaient les variables les plus significatives dans l'esprit des gens qui établissaient les prix des terres.  相似文献   
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