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151.
Abstract

In any discussion of landscape characterisation the elephant in the room is the question of just what is landscape? Another way of putting this question is to simply ask: ‘How would you characterise landscape?’ What this implies is that there is a certain circularity in landscape characterisation because, through the very act of characterising landscape, one is also defining what one means by landscape. The European Landscape Convention’s definition of landscape as ‘an area, as perceived by people, whose character is the result of the action and interaction of natural and/or human factors’ suggests a similar circularity because the character of an area, as it results from the action of natural and/or human factors, is dependent upon human perception, which is presumably also, in addition, one of the human factors acting upon the landscape. This circularity, or ‘circulating reference’, to use Bruno Latour’s term, is fundamental to Denis Cosgrove’s analysis of the origin of the modern concept of landscape as scenic space, and his analysis, we would suggest, helps explain some of the questions raised in this special issue concerning landscape characterisation and the future character of landscape .  相似文献   
152.
This study uses several years of effluent quality data from 43 sites where online monitoring has been operational for many years resulting in the accumulation of high-resolution data sets. The data show a highly repeatable, seasonal dependence of effluent turbidity on temperature. This has been modelled with simple techniques producing a generic model that is neither data hungry nor requires site calibration. Viscosity-based mechanisms are proposed and discussed. These mechanisms differ from conventional assumptions of suspended solids peaks being solely flow related and or ascribed to ‘spring sloughing’. The proposal is that the organic loading of the filter and the physical temperature effects on settlement velocity are both as influential as hydraulic loading in determining effluent suspended solids concentration. Application of the models enables improved design for new/upgraded units and more accurate capacity assessment of trickling filters and humus tanks enabling improved operational risk management of compliance failure.  相似文献   
153.
This paper details the laboratory processes used to fabricate CdS/CdTe solar cells at the National Renewable Energy Laboratory. The basic fabrication technique includes low‐pressure chemical vapor deposited SnO2 , chemical‐bath deposited CdS, close‐spaced sublimated CdTe, solution‐CdCl2 treatment, and an acid‐contact etch, followed by application of a doped‐graphite paste. This paper also describes the results of a reproducibility study in which cells were produced by multiple operators with an average AM1·5 efficiency of 12·6%. And finally, this paper discusses process sensitivities and alternative cell fabrication procedures and reports the fabrication of a cell with an AM1·5 efficiency of 15·4%. Copyright © 1999 John Wiley & Sons, Ltd.  相似文献   
154.
Jet engine components need protective coatings to function against both high-temperature and environmental effects. Ingested calcium–magnesium–aluminosilicates (CMAS) dust particulates are extremely detrimental to the life of the coatings. However, many methods exist to investigate the infiltration of CMAS into these coatings with each method exploring a different aspect of the degradation process. To probe the overlap in these methods, this study focuses on the effect of grain size, areal density, and aspect ratio on the infiltration of CMAS into yttria stabilized zirconia. The infiltration depths ranged from 6 up to 85 µm depending on the test conditions.  相似文献   
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