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H. Volkert 《Meteorology and Atmospheric Physics》1990,43(1-4):231-234
Summary A model orographiy is constructed for a large portion of the Alpine region with nearly equidistant zonal and meridional resolution (3.3 km). Major valleys and massifs, which tend to be smeared out by averaging a high resolution database, are manually reconstructed. A comparison along a crosssection over the crest line of the Eastern Alps in both physical and Fourier space reveals the characteristics of different model resolutions.With 3 Figures 相似文献
995.
Lars H. Blikra 《Engineering Geology》1990,29(4):365-376
Rapid mass movements are common features of hilly or mountainous terrains, and depending on the type of movements or processes involved these give rise to characteristic deposits. Identification of these deposits in mapping programmes gives a clue as to their mode of origin (rockslide/rockfall, snow avalanche, debris flow, fluidal sediment flow) and this can be used to predict rapid mass movements in the future.
A case story from western Norway is described and the value of mapping such deposits for land-use planning and hazard estimation stressed. 相似文献
996.
H. Klapper 《洁净——土壤、空气、水》1990,18(1):81-92
The most important measure is that the freshwater demand of 0.5 m3 per t beet processing is strictly kept to or fallen below, to which a catalogue of measures with ten points is presented. The wastewaters which cannot be used again have to be stored prior to the final purification in order to compensate for quantities and concentrations, aerated storage ponds being successful for small sugar factories as the purification technology. For this, three cases are described as examples: supplementary equipment of two anaerobic ponds with a rod-roll aeration, by which within two months (May to July) the BOD3 is reduced from 1,200 to 11 mg/l. The aeration of a pond of 12.5 ha (370,000 … 500,000 m3) by means of a centrifugal aerator (45 kW) does not lead to completely aerobic conditions: Accumulation up to 350 t BOD5, 200 t organic acids at a reduction of 100 t sulphate, 45 t of which being converted via sulphides by photoautotrophic sulphur bacteria. This combination of anaerobic and aerobic processes is very economical. At aeration with ca. 1 W/m3 in the third case in summer there are achieved wastewater loads which are of a receiving-water quality. 相似文献
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A. H. Hadjian 《地震工程与结构动力学》1989,18(2):217-231
The reduction of the spectral accelerations to account for inelastic response of structures as given by the 1976 Regulations for the Federal District of Mexico is evaluated relative to the records obtained at the Secretaria de Communicaciones y Transportes (SCT) during the September 19, 1985 Mexico earthquake. It is concluded that the 1976 Regulations do not treat all types of structural systems equally. On a relative basis the 1976 Regulations provide less protection for those structures designed to larger values of ductility factors. This could have contributed, together with other characteristics of the ground motions and construction practices, to the heavy damage of highrise buildings in Mexico City. 相似文献
1000.
The National Defense University's study of climate change to the year 2000 was based largely on the judgments of the members of two expert panels. Although the study has been widely distributed and apparently read by policy makers in the U.S. and abroad, the method of eliciting and analyzing expert judgment has not been critically reviewed. This paper uses the literature on judgment and subjective probability to evaluate the expert judgment methods used in the study.The National Center for Atmospheric Research is sponsored by the National Science Foundation. 相似文献