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81.
The relative orientations of various VLBI celestial reference frames are evaluated on the basis of coordinate differences of common sources. It is shown that an accuracy better than 0.001 can be achieved. Possible regional deformations in the different catalogues are investigated; they are found to reach a few 0.001 in some restricted zones. The application of these studies to the realisation of a combined celestial reference frame consistent with the BIH Terrestrial System is outlined.  相似文献   
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The paper deals with a numerical integrated procedure to calculate the effects of the interaction between sea waves and a tripod-type steel gravity platform. The main aspects to be taken into account for a reliable wave loading analysis of such a new type of platform are emphasized. Among them, the field perturbation effect due to the large bodies presence is analysed. Finally, some principal results in terms of structure global loads obtained by the numerical integrated procedure are presented.  相似文献   
85.
The fauna composition, ecological groups, and life forms of Harpacticoids of soft littoral grounds from 15 sites off the Karelian coast in Kandalaksha Bay of the White Sea were studied. Six types of harpacticoid taxocens with different sets of dominating species are described. On silty sands with clear signs of desalination, the Stenchelia palustris taxocen is common; medium-grained sands are characterized by the Heterolaophonte minuta, Paraleptastacus kliei — Huntemannia jadensis, and Amphiascoides nanus — Scottopsyllus minor taxocens; while on coarse sands, the Ameira parvula and Ameira scotti — Mesochra lilljeborgi taxocens have developed. The diversity of the taxocens is partly explained by the differences in the grain-size composition and salinity at different sites. In addition, groups of various taxocens dwelling on the same type of the sediments were found in different minor bights of the coastline.  相似文献   
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Satellite imagery and offshore magnetic data were analysed to correlate regional tectonic elements on the inner continental shelf off Konkan and the adjacent Deccan plateau. Three statistically important lineament trends—N-S, WNW-ESE and ENE-WSW—that prevail on land are correlatable well with the offshore trends. This positive correlation suggests simultaneous deformation. The major magnetic lineament observed off Jaigad Bay, west coast of India, may be the extension of onshore lineaments. The correlation of both the offshore and onshore trends indicates that the fracture pattern of the crystalline basement has also controlled the offshore structural pattern.  相似文献   
88.
M. J. Martres 《Solar physics》1989,119(2):357-384
This paper consists of two parts. We first discuss recent general results on the study of properties of flare homology, and their relevance to the physical interpretation of the flare phenomenon at large. We devote particular attention to the discovery of homologous flares which occur in rapid succession, within a few minutes of each other in many cases. We name these kind of flares rafales. These flares signal the existence of several episodes of energy release within the same magnetic configuration. We also show the existence of particular sites in the solar atmosphere which have peculiar characteristics in terms of solar rotation, and where recurrent flaring may take place over and over again in different solar rotations. This indicates that the disturbance causing the emergence of activity is deep seated, below the solar photosphere. Finally, in the second part, we discuss an extensive set of observations of two homologous flares of a rafale, stressing the dynamic aspects of the observations, particularly the presence of peaks in the vertical component of the velocity field. These results are shown to be in agreement with studies of filament activations and the surging arches which are observed before the flash phase of solar flares.  相似文献   
89.
The author examines circular labor migration in Fiji. "This paper is organized into five sections. The first section provides a brief discussion of two major perspectives of labour circulation in developing countries. The second section presents the state of the Fijian village in the context of the current pattern of uneven development in Fiji. The practice of labour circulation by Fijian villagers is dealt with in the third section. In the last two sections, issues concerning the maintenance of the polarized pattern and the preservation of the village mode of production are discussed."  相似文献   
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