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In this work, the canonical biplot (CB) method (Vicente‐Villardón, 1992; Gower and Hand, 1996) is used to determine the origin, distribution, conservation and pollution state of the different types of stones used in the construction and restoration of monuments of great historical interest. The stone materials (sandstones) used in the Cathedral of Ciudad Rodrigo (Salamanca, Spain) have been used to assess the usefulness of the method. The age of this monument (eight centuries), together with the surrounding environmental conditions, have especially contributed to the pollution of the stone masonries, in comparison to the same stones identified in the original quarries. The CB method has allowed us to: (a) identify the sandstone varieties used in the construction; (b) locate the original quarries of these sandstones; (c) locate these materials in the building, and (d) detect the pollution and deterioration affecting the stones in the monument, in comparison to the stones of the original quarries. Copyright © 2005 John Wiley & Sons, Ltd. 相似文献
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Awoke Dagnew Donald Scavia Yu‐Chen Wang Rebecca Muenich Colleen Long Margaret Kalcic 《Journal of the American Water Resources Association》2019,55(5):1288-1305
A large international watershed, the St. Clair‐Detroit River System, containing both extensive urban and agricultural areas, was modeled using the Soil and Water Assessment Tool (SWAT) model. The watershed, located in southeastern Michigan, United States, and southwestern Ontario, Canada, encompasses the St. Clair, Clinton, Detroit (DT), Sydenham (SY), Upper, and Lower Thames subwatersheds. The SWAT input data and model resolution (i.e., hydrologic response units, HRUs), were established to mimic farm boundaries, the first time this has been done for a watershed of this size. The model was calibrated (2007–2015) and validated (2001–2006) with a mix of manual and automatic methods at six locations for flow and water quality at various time scales. The model was evaluated using Nash–Sutcliffe efficiency and percent bias and was used to explore major water quality issues. We showed the importance of allowing key parameters to vary among subwatersheds to improve goodness of fit, and the resulting parameters were consistent with subwatershed characteristics. Agricultural sources in the Thames and SY subwatersheds and point sources from DT subwatershed were major contributors of phosphorus. Spatial distribution of phosphorus yields at HRU and subbasin levels identified locations for potential management targeting for both point and nonpoint sources and revealed that in some subwatersheds nonpoint sources are dominated by urban sources. 相似文献
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E. Stephanou 《Die Naturwissenschaften》1989,76(10):464-467
Dedicated to Prof. Dr. A. Buchs, University of Geneva, on the occasion of his 60th birthday. 相似文献