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As features of the landscape, waterfalls have been studied extensively by geographers, but the names given to these landforms have received relatively little scholarly attention. This paper examines the naming of waterfalls and addresses the question of classifying these hydronyms. The subject is considered in a global historical context, focusing on place names in the anglophone world. Until the 18th and 19th centuries, relatively few waterfalls were named. With the beginning of the Industrial Revolution, water power rose in economic importance, and at the same time, there was a growing scientific and aesthetic engagement with the landscape. These developments are suggested as reasons for the increased interest in waterfalls which were then being recorded in topographical literature and on maps, individual names being given to increasing numbers of falls. European exploration added to the knowledge of the world's waterfalls, many of which were given names by their ‘discoverers’. This naming process accelerated with the growth of domestic and overseas tourism which exploited scenic resources such as waterfalls. Until now, research on the names of waterfalls has been fragmentary, and the classification of these hydronyms has been neglected. This paper demonstrates that waterfall names can be classified in accordance with a recognised toponymic typology. Using examples drawn from waterfall guidebooks, databases, maps, and other sources, the following discussion supports George Stewart's claim that his toponymic classification is valid for place names of all kinds.  相似文献   
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The vallum is a major earthwork along the south side of Hadrian's Wall. All surface traces of it have been obliterated over a 500-m-long stretch past the fort of Vindobala at Rudchester, Northumberland. To the west of the fort, the vallum's course had previously been delineated by running shear-wave seismic refraction lines to obtain depth profiles of rockhead. We have now run more seismic refraction lines, using both shear waves and compressional waves, to the south-west and south of the fort, and thereby located the complete course of the vallum at Vindobala. The seismic refraction technique is successful at this site because the glacial drift cover is thin, so the vallum ditch was cut down into bedrock. During the second phase of seismic work, compressional waves gave better results than shear waves. Previously, test profiles using compressional waves had failed to locate the vallum ditch west of the fort where the surface elevation is lower; we now interpret that failure as being due to a shallow water table within the drift, which would have eliminated the compressional-wave velocity anomaly. Although the vallum does not pre-date the fort at Vindobala, its asymmetrical course around the fort suggests that it may already have been under construction to the west when the decision to build the fort was taken.  相似文献   
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The verandah, a characteristic feature of Australia architecture, is commonly found in many parts of the world. Introduced into Australia by the British at a time when verandahs were popular both in England and the colonies, these structures were not merely practical responses to climatic conditions. It is argued that beyond the functional considerations of comfort and convenience, verandahs and similar structures are a response to and an expression of landscape aesthetic preferences for which Appleton has offered an explanation in terms of prospect-refuge theory. The overlapping prospect-refuge and information processing theories are discussed in relation to the survival value of leisure to provide a possible explanation of the widespread popularity of verandahs.  相似文献   
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The primary focus of a structural shake table system is the accurate reproduction of acceleration records for testing. However, many systems deliver variable and less than optimal performance, particularly when reproducing large near-field seismic events that require extreme table performance. Improved identification and control methods are developed for large hydraulic servo-actuated shake table systems that can exhibit unacceptable tracking response for large, near-field seismic testing. The research is presented in the context of a 5-tonne shake table facility at the University of Canterbury that is of typical design. The system is identified using a frequency response approach that accounts for the actual magnitudes and frequencies of motion encountered in seismic testing. The models and methods developed are experimentally verified and the impact of different feedback variables such as acceleration, velocity and displacement are examined.

The methods show that shake table control in testing large near-field seismic events is often a trade off between accurate tracking and nonlinear velocity saturation of the hydraulic valves that can result in severe acceleration spikes. Control methods are developed to improve performance and include both acceleration and displacement feedback to reduce the acceleration spikes, and record modification, where the reference signal is modified to conform to the shake table's operational parameters. Results show record modification gives exact tracking for near-field ground motions, and optimal system response for reference signals with velocity components greater then the system capabilities. Overall, the research presents a methodology for simple effective identification, modelling, diagnosis and control of structural shake table systems that can be readily generalised and applied to any similar facility.  相似文献   
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BOOK REVIEWS     
Book Reviews in this Article: Danielle Jacquart and Claude Thomasset, Sexuality and Medicine in the Middle Ages,. David Levine, Reproducing Families. The political economy of English population history. Mikiso Hane, Reflections on the Way to the Callows: Rebel Women in Pre-war Japan. Sandra M Gilbert and Susan Gubar, No Man's Land: The Place of the Woman Writer in the Twentieth Century. Nancy F. Cott, The Grounding of Modern Feminism. Brian Harrison, Prudent Revolutionaries, Portraits of British Feminists between the Wars. Birgit Sawyer and Anita Goransson (eds), Manliga strukturer och kvinnliga strategier. Susan Bridger, Women in the Soviet Countryside: women's roles in rural development in the Soviet Union. Veronica Strong-Boag, The New Day Recalled: Lives of Girls and Women in English Canada, 1919–1939.  相似文献   
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