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Václav Bucha Reviewer F. Rein Reviewer J. Bochníček 《Studia Geophysica et Geodaetica》1977,21(3-4):350-360
Summary As a result of investigating the relations between the variations of geomagnetic activity and meteorological factors [1, 2] a mechanism of solar-terrestrial relationships and a model of the changes of atmospheric circulation in the Northern Hemisphere are proposed; this provides an explanation of the causes of the fluctuation of the climate, of dry and cold periods and differing vegetation conditions in various years in dependence on the intensity of geomagnetic activity. 相似文献
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František Rein 《Studia Geophysica et Geodaetica》1972,16(3):306-306
Ohne Zusammenfassung 相似文献
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Ice ridges form a difficult obstacle for ice navigation. Despite this fact, the resistance of ships in ridges has been investigated very little.A trial was performed with the Finnish icebreaker APU (propulsion machinery power of 8·8 MW) in April 1974 in the Baltic, in order to measure its resistance in ridges.Most of the 11 ridges were so massive that the ship could not penetrate through them by a continuous mode, the ramming mode had to be used.When the ship was penetrating a ridge, its speed and the propeller revolutions were registered for determining the resistance. A doppler radar was used for measuring ship spped.In case the ship was stopped in the ridge it was extracted, reversed and accelerated for the next ram. The time history was registered for determining the ship's speed of advance.Before starting a test, the ridge profile above the water level was measured. This was simply done by using a levelling instrument.The main object of the test was to determine the ship's speed of advance. The results, i.e. ice resistance, ship speed and ridge characteristics were analysed on three levels: momentary values average values for rams and average values for a series of rams in one ridge.The test series presented in the article was the first one in full scale in which the speed of the advance of a ship moving by ramming was determined and the ridge profiles were mapped. The measuring system developed worked well. As results the tests gave data of the ship's resistance and of the ship's speed of advance in ridges. 相似文献
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This case study demonstrates how natural heterogeneities of formation and injection waters can be applied to a number of production related applications, extending into the mature life of a reservoir. Break-through of injection water, identification and characterisation of production intervals and evaluation of responses to operational events are some of the possible applications during production.The Oseberg Øst oil field in the North Sea represents a complex situation with commingled production from all Brent Group formations. The Sr isotope composition is an excellent parameter for defining the natural baseline of formation water, with a good spatial resolution and vertical stratification. Aquifer water from the Utsira Formation is injected for pressure support, and reinjection of produced water has also been applied since the onset of water production. Utsira Formation water has high Mg, low Ba and low Sr content compared to the reservoir formation waters. Isotopic compositions (δD and 87Sr/86Sr) are also distinct. A non-reactive behaviour of Ba and Sr is verified from binary cross-plots and geochemical modelling. Break-through of injection water could be identified in five production wells based on Ba/Mg ratios. In one of the reservoir compartments (Beta Saddle), water injection points were changed after approximately three years. The Ba/Mg ratio could also identify the second injection water break-through in one of the wells due to an intermediate period of higher formation water content. Since the Sr content in the Utsira water is low, the 87Sr/86Sr ratio is a good natural tracer for formation water movements even at high ratios of injected water. In particular, the vertical stratification of 87Sr/86Sr is useful for quantifying production from different intervals in commingled wells. A methodology for using operational events, such as production allocations or shut-ins, for characterisation of production zones is discussed. 相似文献