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Polish Baltic coast, especially in summer season, is one of the most attractive, in terms of tourism, regions of the country. From a geotourist viewpoint, particularly attractive are the cliff sections. The attractiveness of a given coast fragment is also determined by tourist facilities provided there and anthropogenic objects which are of interest to tourists. The coast section between Władysławowo and Jastrzębia Góra is particularly attractive. This is thanks to its diverse geological structure visible in cliff outcrops, and varied cliff relief cut by deep gullies. The geological sediments to be observed there include brown coal outcrops. The attractiveness of the coast is enhanced by its geographical location. It is the northernmost fragment of Poland’s territory. An additional attraction is provided by anthropogenic objects, e.g. the lighthouse in Rozewie or various forms of technical shore defence against abrasion.
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Some probabilistic properties of surf parameter

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The amount of sand moving parallel to a coastline forms a prerequisite for many harbor design projects. Such information is currently obtained through various empirical formulae. Despite so many works in the past, an accurate and reliable estimation of the rate of sand drift has still remained a problem. It is a non-linear process and can be described by chaotic time-series. The current study addresses this issue through the use of Adaptive Neuro-Fuzzy Inference System (ANFIS). ANFIS is about taking an initial fuzzy inference system (FIS) and tuning it with a back propagation algorithm based on the collection of input-output data. ANFIS was developed to predict the sand drift from a variety of causative variables. The structure and algorithm of ANFIS for predicting the rate of sand drift is described. The Adaptive Neuro-Fuzzy Inference System was validated by confi rming its consistency with a database of specifi ed physical process.
Gut contents of Pygospio elegans Claparede (Spionidae) individuals collected in the Polish coastal zone of the Baltic were analysed. Guts of almost all the P. elegans (89-100%) were found to contain sand grains and detritus. Microalgae (Bacillariophyta, Chlorophyta, Flagellata) occurred in the guts of 8-100% P. elegans individuals. Noteworthy was the finding, in the P. elegans gut contents, of oligochaeta remains, indicative of some predatory behaviour of the polychaete. The oligochaete contribution to the P. elegans food increased with polychaete size (from 33 to 100%). Therefore, P. elegans in the Baltic population should be regarded as omnivores rather than suspension feeders- deposit feeders they have been classified with so far.
Concentrations of sulphate ions and particle size distributions were measured in the marine boundary layer using a ten-cascade Berner impactor at Hel between December 1997 and March 1998, and with a filter packin Gdynia from February to May 2001. In the marine boundary layer over the Hel Peninsula the presence of natural sea-salt and non-sea-salt sulphate ions (nssSO4 2−) was confirmed in the aerosols. The nssSO4 were present in all size ranges only in December 1997 and in the first half of January 1998, making up an average of 83.7±2.4% of the total sulphate content. In the other winter months, nssSO4 2− were recorded only in aerosols of diameters from 0.4 to 1.5 μm, and their average contribution dropped by over 20%. The extended growing season in the Southern Baltic resulted in the formation of fine particles that appeared in the marine boundary layer in early winter. At that time the proportion of nssSO4 2− in ultra-fine particles ranged from 75.7% to 100%. The concentration of nssSO4 2−, which varied from 0.8 to 2.3 nmol m−3 in particles < 0.4 μm in size probably constituted the natural background aerosol population in the relatively clean coastal environment of the Southern Baltic Sea. In the coastal urbanised area of Gdynia, the sulphate concentration in aerosols was higher than at Hel (av. 75.3 nmol m−3) but the proportion of nssSO4 was low, of the order of 24%. Sea salt was then the dominant source of sulphate.
Prorocentrum minimum (Pavillard) Schiller has occurred in the Gulf of Gdańsk in low abundance for several years. However, in summer 1997 a significant increase in the numbers of cells was noted. In the same year a P. minimum bloom was recorded for the first time in one of the harbour basins in Gdynia, giving rise to a brown-red coloration of the water.
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Two wave theories are applied in calculations of longshore sediment transport rates: the second Stokes approximation and the cnoidal theory. These approaches are used to model sand motion in nearshore locations beyond and within the surf zone. Wave-current interaction in the nearbed layer and bed shear stresses are solved using a momentum integral method, whereas sediment transport is described by a three-layer model encompassing bedload, contact load and suspended load. Computational results for asymmetric waves are compared with the results obtained using linear wave theory and the conventional sediment transport models of Bailard (1981), Bijker (1971) and Van Rijn (1993).
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