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Sheep usage of part of the summit of Glas Maol was monitored by pellet‐group counts to determine impact on Carex bigelowii‐Racomitrium lanuginosum moss heath. The effects of a fenced skiing corridor in giving shelter and disrupting ranging movements were assessed. Dung deposition was appreciable only from June to September each year, and heaviest in July and August; occupance seemed to depend on the presence of substantial quantities of green herbage. Dung deposition was much greater within 5 m of the fence, probably because of its sheltering effect. The estimated May‐October stocking of 1.1 sheep ha‐1 on the main plateau is surprisingly heavy for the altitude, whereas usage by red deer was negligible.  相似文献   
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Even though nationally televised addresses provide the president the opportunity to speak directly to the American people and are a potentially powerful tool for influencing public opinion, scholars have little understanding of the people the president speaks to when he delivers televised addresses. This study examines the audience for televised presidential addresses. Specifically, it looks at the size of the audience for televised addresses, the differences between people who watch televised addresses and those who do not watch, and explains why some people watch the addresses while others do not. To answer these questions I use a unique set of national opinion surveys conducted by Richard Wirthlin, who served as Ronald Reagan's pollster throughout Reagan's years as president. I find that even though televised addresses are given on network television, the president is not assured a large television audience. Moreover, I find that there is a difference between people who watch televised addresses and those who do not, and that the demographic characteristics, personal concerns, and especially the political participation of a person explain why people watch or do not watch televised addresses.  相似文献   
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Various loss assessment methodologies have been proposed and developed over the past decades to provide risk assessment on a regional scale. There is an increasing need, however, to provide engineers with practical tools for building-specific loss assessment. Recently, progress has been made towards probabilistic loss models such as the PEER framework. However, as comprehensive probabilistic methodologies could be too complex for practicing engineers, this article presents a simplified probabilistic loss assessment methodology that builds on a direct displacement-based framework. The methodology is tested via examination of two RC frame buildings and encouragingly shows similar results to the PEER methodology.  相似文献   
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