This article examines some general atmospheric circulation and climate models in the context of the notion of “memory”. Two kinds of memories are defined： statistical memory and deterministic memory. The former is ...This article examines some general atmospheric circulation and climate models in the context of the notion of “memory”. Two kinds of memories are defined： statistical memory and deterministic memory. The former is defined through the autocorrelation characteristic of the process if it is random （chaotic）, while for the latter, a special memory function is introduced. Three of the numerous existing models are selected as examples. For each of the models, asymptotic （at t →∞） expressions are derived. In this way, the transients are filtered out and that which remains concerns the final behaviour of the models.展开更多
The present investigation has been fulfilled with a view to the future nuclear power station constriction near the Belene Island.Sediment loads and sediment transportation are important factors for the technical water...The present investigation has been fulfilled with a view to the future nuclear power station constriction near the Belene Island.Sediment loads and sediment transportation are important factors for the technical water supply of the nuclear station Belene.The paper deals with change of suspended sediment load at Bulgarian part of the Danube River downstream of the Iron Gates.Recent data on suspended sediment loads for the hydrometric gauge station at Svishtov have been collected,computed and presented.The results obtained discover the time variability of the sediment loads,climate change and the anthropogenic impact on the suspended sediments.The tendency of alteration and inter-annual variability of the suspended sediments are investigated and characteristics of average annual,monthly and maximal values are shown.In the material archive granulometric data are presented for this part of the Bulgarian stretch before the Iron Gates construction in the conditions of the natural sediment regime.There are statistical parameters of the studied characteristics of the river turbidity and discharge before and after the anthropogenic impact.The increase of the absolute minimal turbidity has been determined after the Iron Gate I as a result of activation of the bed processes and hydro-morphological changes.展开更多
文摘This article examines some general atmospheric circulation and climate models in the context of the notion of “memory”. Two kinds of memories are defined： statistical memory and deterministic memory. The former is defined through the autocorrelation characteristic of the process if it is random （chaotic）, while for the latter, a special memory function is introduced. Three of the numerous existing models are selected as examples. For each of the models, asymptotic （at t →∞） expressions are derived. In this way, the transients are filtered out and that which remains concerns the final behaviour of the models.
文摘The present investigation has been fulfilled with a view to the future nuclear power station constriction near the Belene Island.Sediment loads and sediment transportation are important factors for the technical water supply of the nuclear station Belene.The paper deals with change of suspended sediment load at Bulgarian part of the Danube River downstream of the Iron Gates.Recent data on suspended sediment loads for the hydrometric gauge station at Svishtov have been collected,computed and presented.The results obtained discover the time variability of the sediment loads,climate change and the anthropogenic impact on the suspended sediments.The tendency of alteration and inter-annual variability of the suspended sediments are investigated and characteristics of average annual,monthly and maximal values are shown.In the material archive granulometric data are presented for this part of the Bulgarian stretch before the Iron Gates construction in the conditions of the natural sediment regime.There are statistical parameters of the studied characteristics of the river turbidity and discharge before and after the anthropogenic impact.The increase of the absolute minimal turbidity has been determined after the Iron Gate I as a result of activation of the bed processes and hydro-morphological changes.
