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A robust debate among coastal geomorphologists as to the processes by which beach‐ridge plains around Australia have formed was initiated by a former President of the Institute of Australian Geographers. This review gives special consideration to the work of Jack L. Davies, whose academic contributions to coastal geomorphology in Australia have not always been appropriately acknowledged when explaining how similar plains have evolved elsewhere in the world. Davies recognised that relatively steep storm waves caused erosion (cut) on beaches, whereas less steep long‐period swell waves returned sand (fill). He considered the beach berm to be the nucleus on which a beach ridge formed, which could subsequently develop into a foredune, in contrast to cobble ridges that were deposited during storms. Offshore conditions regulate supply of sand to the shoreline, partly through effects on wave refraction, with higher rates of supply where the nearshore is shallow. It was apparent to Davies that the elevation of successive ridges might, but not necessarily, provide evidence of past changes of sea level, despite adornment by variable amounts of windblown dune sand. Morphodynamic understanding of long‐term coastal evolution, based on radiocarbon dating chronologies, has demonstrated that Australian coastal plains formed over the past ~6,000 years when sea level has been close to its present level, in contrast to several documented locations in the northern hemisphere where the sea has been rising for the past few millennia. Particularly insightful were observations by Davies that ridge formation could be influenced by a range of factors including changes in sea level, storminess, or sediment supply. These factors acting singly or in combination seem likely to change in the future. Understanding such responses remains a high priority and can be addressed by new technologies, such as light detection and ranging, optically stimulated luminescence dating, ground‐penetrating radar, and computer simulation.  相似文献   
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Abstract: Re‐reading the economic landscape of the western world as a largely non‐capitalist landscape composed of economic plurality, this paper demonstrates how economic relations in contemporary western society are often embedded in non‐commodified practices such as mutual aid, reciprocity, co‐operation and inclusion. By highlighting how the long‐overlooked lived practices in the contemporary world of production, consumption and exchange are heavily grounded in the very types and essences of non‐capitalist economic relations that have long been proposed by anarchistic visions of employment and organization, this paper displays that such visions are far from utopian: they are embedded firmly in the present. Through focusing on the pervasive nature of heterodox economic spaces in the UK in particular, some ideas about how to develop an anarchist future of work and organization will be proposed. The outcome is to begin to engage in the demonstrative construction of a future based on mutualism and autonomous modes of organization and representation.  相似文献   
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Community‐based conservation is experiencing a crisis of identity and purpose as a result of a disappointing track record and unresolved deficiencies. The latter include over‐simplified assumptions and misconceptions of “community,” the imposition of externally designed and driven projects at the community level, a focus on conservation outcomes at the expense of community empowerment and social justice, and limited attention to participatory processes. New approaches are urgently needed to address these weaknesses and to counter a rising trend towards environmental protectionism and a preference for conservation approaches at an eco‐regional scale that threaten the interests of local and Indigenous communities. We propose that three core principles of community‐based participatory research (CBPR)—(1) community‐defined research agenda; (2) collaborative research process; and (3) meaningful research outcomes—hold much promise. Drawing on the experience of a research partnership involving the James Bay Cree community of Wemindji, northern Quebec, and academic researchers from four Canadian universities, we document the process of applying these principles to a community‐based conservation project that uses protected areas as a political strategy to redefine relations with governments in terms of a shared responsibility to care for land and sea. We suggest that basic assumptions of CBPR, including collaborative, equitable partnerships in all phases of the research, promotion of co‐learning and capacity building among all partners, emphasis on local relevance, and commitment to long‐term engagement, can provide the basis for a revamped phase of community‐based conservation that supports environmental protection while strengthening local institutions, building capacity, and contributing to cultural survival.  相似文献   
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Heavily corroded metal artifacts recovered from the site of an 18th-century steel cementation furnace in Trenton, New Jersey, are cast iron altered by internal oxidation. The progress of the internal oxidation process was followed by comparison with the microstructure of cast iron exposed to high temperature in a wood-burning fireplace. The graphite flake structure of the cast iron allows deep, rapid penetration of oxygen that reacts at the iron–carbon interfaces within the iron to form iron oxides that eventually replace the graphite flakes. Microprobe analyses show that the silicon in the cast iron is converted to knebelite that also serves as the host for phosphorus. Sulfur dispersed in the internal oxidation product and porosity appear to be responsible for rapid rusting of the artifacts. Internal nitriding accompanies the oxidation. The Trenton artifacts are interpreted as grate bars from the fire box of a cementation furnace.  相似文献   
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Architectural reconstructions of plankhouses are central to the study of household and community organization on the Northwest Coast of North America. However, the sample of substantially excavated houses is constrained by their size, stratigraphic complexity, and typically limited surface expression. We present the results of a magnetic gradiometry survey of the Dionisio Point site (DgRv-003) village, occupied ca. a.d. 500–700 on the coast of British Columbia, Canada. Survey of four house platforms reveals patterning of magnetic anomalies consistent with the structure of shed-roof houses, a design recorded ethnographically and identified archaeologically at the site. These results suggest a consistent pattern of spatial and, potentially, social organization of the households. The similarity of patterns suggests that magnetometry may be useful for guiding plankhouse excavations elsewhere on the Northwest Coast, providing a means for expanding our knowledge of houses without relying solely on traditional excavation methods.  相似文献   
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A small iron gun recovered from the wreck of the Caroline warship Swan has been identified as a drake, a lightweight tapered-chamber design dating from the 1620s. It is the only known cast-iron example of such a piece made by John Browne, gunfounder to Charles I, who was the leading figure in its development and manufacture in England. The gun was found together with an associated carriage, port-lid, and case shot appropriate to its calibre.
© 2004 The Nautical Archaeology Society  相似文献   
39.
Colin McFarlane 《对极》2004,36(5):890-916
This paper is concerned with the various ways in which geographical imaginations are inflected in politics. It draws on examples from a three‐way partnership of civil society organisations based in Mumbai, India. This movement seeks to reconfigure the governance of anti‐poverty strategies by placing "poor people" at the centre of its activities. The partnership, which refers to itself as the Alliance , is involved in the mobilisation and creation of a range of alternative geographical imaginations that are inflected in the production of new spaces of political engagement. By exploring two of the Alliance's strategies—enumerations and exhibitions—I will illustrate some of the ways in which these alternative geographical imaginations feature in the creation of spaces of political engagement. These strategies involve the practical demonstration of the capacities of the poor to donors and states, and reflect a particular conception of the poor and social change.
The spaces of political engagement formed in part through the Alliance's work depend significantly on a commitment to non‐party alignment, an approach that has received criticism from NGOs and commentators involved with urban poverty. I will argue that the Alliance represents a broad development alternative—rather than a form of alternative development—which nonetheless is making substantial progress in the politics of citizenship in Mumbai.  相似文献   
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