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941.
Geographic information has a great potential to be re-used when supported by mechanisms for its discovery. Above all, the quality of a catalogue service is the key feature supporting users in the discovery process. So far, there have been in existence various methodologies dealing with the normalized evaluation of quality with respect to catalogue services. Their biggest weakness seems to be in the depth of quality testing, i.e. some influences are beyond the scope of evaluation of these methodologies with respect to quality in catalogue services. In this study, the quality of 45 catalogue services across Europe was verified with the proposed normalized evaluation methodology originating from documents within the INfrastruture for SPatial InfoRmation in Europe (INSPIRE) framework. This paper discusses the (statistical) influence of factors that may significantly change the results of catalogue service testing. The proposals for improving the existing INSPIRE normalized evaluation procedure are applicable for any spatial data infrastructure and/or Digital Earth component using the Open Geospatial Consortium Catalogue Service for the Web as a basis. 相似文献
942.
Evaporation from porous rock plays an important role in weathering processes. In the case of salt weathering, the evaporation rate controls supersaturation of salt solutions within pores and the amount of precipitated aggressive salts, therefore weathering occurs mostly in places with intense evaporation. Evaporation also strongly affects frost, hydric and biogenic weathering, as these are influenced by water content and its temporal changes. Despite its importance, evaporation from porous rocks has seen little scientific focus. We present a study on evaporation from bare sandstone, one of the most common rocks affected by weathering. A new method that measures the evaporation rate from the surfaces of sandstone samples under field microclimate was developed and tested. Also, a simple calculation of 1D evaporation rate from bare sandstone surfaces based on Fick's law of diffusion is presented. The measurement was performed using sandstone cores (with a set depth of the vaporization plane) in a humid continental climate and measured on a roughly monthly interval for about 1 year. For the calculations, a laboratory-measured water-vapour diffusion coefficient of the sandstone, in-situ seasonally measured vaporization plane depth, and values of air humidity and temperature were used. The sensitivity analyses showed that the most important factor controlling the evaporation rate was the vaporization plane depth, while seasonal and spatial changes of air humidity and temperature were of lesser importance. The calculated evaporation rate reasonably follows measured values. For its simplicity and the small number of parameters required, the proposed method has the potential to improve knowledge of weathering and living conditions of endolithic and epilithic organisms. Further research should focus on factors affecting the evaporation rate (wind, hygroscopicity, hydrophobicity, etc.) to improve the accuracy of the calculations, as well as to test the applicability of the method for other lithologies and climates. © 2020 John Wiley & Sons, Ltd. 相似文献