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Current research on USS Arizona is focused on a minimum-impact technique for calculating corrosion rate of the battleship's steel hull by analysing physical and chemical properties of marine encrustation covering the exposed hull. An equation is derived that allows concretion thickness, density, and total iron content to be used to calculate corrosion rate of steel hull plate.
© 2006 The Authors  相似文献   
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The parliamentary decline thesis overstates the dominance of the executive. The relationship between the executive and legislature is actually far more complex and balanced than is commonly recognised. After exploring recent developments in Australia and New Zealand, this article draws upon an audit of parliamentary modernisation in Britain since the election of New Labour in 1997 and suggests that a reforming parliament occurred during 2001–05 in which an executive with a majority of 166 was forced to acquiesce in the introduction of a raft of reform measures in the House of Commons that were designed to shift the balance of power. At the same time, the ‘transitional’ House of Lords displayed a new-found zeal and activism in a way that further frustrated the executive's control of parliament. This is not to overstate the degree of change: party loyalty remains the primary glue in the executive–legislative relationship and the executive remains dominant. However, it does suggest that in the British context the executive must still work within the limits and constraints of the parliamentary framework.  相似文献   
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Research on coalitions in the policy process has found evidence of both short-term and long-term coalitions. Two possible methodological reasons for the varied results are that (1) there has been little systematic longitudinal research on the topic, and (2) most scholars have not distinguished situations where fundamental versus secondary interests are at stake. This article addresses both points by first applying the Advocacy Coalition Framework (ACF), which distinguishes fundamental from secondary beliefs/interests, and then performing a quantitative analysis of the content of organizations' testimonies regarding automotive pollution control over 26 years. Consistent with the ACF, we find that coalitions of interest groups, legislators, local governments, and agencies are relatively stable over time, despite two potentially disruptive events—the 1973–74 Oil Embargo and the 1980 Elections. On the other hand, there is little support for the ACF's hypothesis that broader beliefs will be more stable than narrower secondary beliefs. Our systematic methodology also enables us to separate the general pattern of stability from interesting exceptions of instability.  相似文献   
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In the 1970s and 1980s, regional analysis was an influential part of archaeological research, providing a discrete set of geographical tools inspired by a processual epistemological and interpretive perspective. With the advent of new technologies, new methods, and new paradigms, archaeological research on regional space has undergone significant changes. This article reviews the state of regional archaeology, beginning with a consideration of its history and a discussion of the fundamental issues facing regional investigations before focusing on developments over the last several years. On one hand, the diversification of archaeological theory has created new paradigms for thinking about human relationships with one another and with the physical environment across regional space; in this regard, historical ecology, landscape archaeology, and evolutionary theory have been particularly influential in recent years. This has led to a corresponding diversification of the traditional methods of regional analysis. Most notably, the advent of powerful digital technologies has introduced new tools, especially those from the geographic information sciences, that build on the quantitative methods of past approaches. The investigation of regional data is no longer based on a discrete toolkit of simple mathematical and graphical procedures for representing spatial relationships. Instead, regional archaeology has matured into a diversity of multiscalar spatial and geostatistical techniques that inform many areas of archaeological inquiry.  相似文献   
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This article focuses on the presence of humans in Siberia and the Russian Far East at the coldest time of the Late Pleistocene, called the Last Glacial Maximum (LGM) and dated to c. 20,000–18,000 rcbp. Reconstruction of the LGM environment of Siberia, based on the latest models and compilations, provides a background for human existence in this region. Most of Siberia and the Russian Far East at c. 20,000–18,000 rcbp was covered by tundra and cool steppe, with some forest formations in the river valleys. Climate was much colder and drier than it is today. Eighteen Upper Paleolithic sites in Siberia are radiocarbon dated strictly to the LGM, and at least six of them, located in southern parts of western and eastern Siberia and the Russian Far East, have solid evidence of occupation during that time span. It seems clear that southern Siberia was populated by humans even at the height of the LGM, and that there was no dramatic decline or complete disappearance of humans in Siberia at that time. The degree of human adaptation to periglacial landscapes in the mid-Upper Paleolithic of northern Eurasia was quite high; humans coped with the cold and dry environmental conditions using microblade technology, artificial shelters, tailored clothes, and megafaunal bones as fuel. An erratum to this article can be found at  相似文献   
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