In this work we present a methodology for the mapping of Snow Water Equivalent (SWE) temporal variations based on the Synthetic Aperture Radar (SAR) Interferometry technique and Sentinel-1 data. The shift in the interferometric phase caused by the refraction of the microwave signal penetrating the snow layer is isolated and exploited to generate maps of temporal variation of SWE from coherent SAR interferograms. The main advantage of the proposed methodology with respect to those based on the inversion of microwave SAR backscattering models is its simplicity and the reduced number of required in-situ SWE measurements. The maps, updated up to every 6 days, can attain a spatial resolution up to 20 m with sub-centimetre ΔSWE measurement accuracy in any weather and sun illumination condition. We present results obtained using the proposed methodology over a study area in Finland. These results are compared with in-situ measurements of ΔSWE, showing a reasonable match with a mean accuracy of about 6 mm.
The aim of this contribution is to describe the removal efficiency of individual fractions of natural organic matter (NOM) during water treatment. Two types of surface water with an increased concentration of NOM of various origins were analysed. It was shown that the NOM removal efficiency depends on the NOM character and reaction conditions. The optimised doses of destabilisation reagents influence especially the removal of hydrophilic charged (CHA) and very hydrophobic acids (VHA) fractions during treatment of both types of raw water (φCHA = 0.78-0.86, φVHA = 0.51-0.88). In contrast, removal of hydrophilic neutral (NEU) fraction was very low (φNEU = 0.13-0.22). and Příspěvek se zabývá odstranitelností jednotlivých frakcí přírodních organických látek (NOM) při úpravě povrchových vod se zvýšeným obsahem NOM různého typu. Výsledky ukazují, že účinnost odstranění NOM závisí na charakteru NOM a na reakčních podmínkách. Při optimalizovaných dávkách destabilizačního činidla byla, při úpravě obou typů vod, nejlépe odstraněna frakce VHA (silně hydrofobní kyseliny) a frakce hydrofilní nabitá (CHA) (φCHA = 0.78-0.86, φVHA = 0.51-0.88). Naopak odstranění hydrofilní nenabité frakce (NEU) bylo minimální (φ = 0.13-0.22).
The paper demonstrates that the wind stress curl as an external vorticity source plays an important role in shaping large scale shallow lake circulations. The analysis of purpose-oriented simultaneous wind and current measurements data from the Hungarian part of Lake Neusiedl reasonably fits well the internal boundary layer development theory over the lake surface. A 2-D vorticity formulation of wind-induced flows is used to demonstrate mathematically the IBL-related large scale circulation generation mechanism well reflected in the measured data. Further validation of the findings is carried out by means of simple 2-D numerical flow modelling, in which details on the flow pattern besides the measurement sites could be also revealed. Wind-induced lake circulations linked to IBL development shows a novelty to be implemented in up-to-date numerical flow models.
Stony soils are composed of fractions (rock fragments and fine soil) with different hydrophysical characteristics. Although they are abundant in many catchments, their properties are still not well understood. This article presents basic characteristics (texture, stoniness, saturated hydraulic conductivity, and soil water retention) of stony soils from a mountain catchment located in the highest part of the Carpathian Mountains and summarizes results of water flow modeling through a hypothetical stony soil profile. Numerical simulations indicate the highest vertical outflow from the bottom of the profile in soils without rock fragments under ponding infiltration condition. Simulation of a more realistic case in a mountain catchment, i.e. infiltration of intensive rainfall, shows that when rainfall intensity is lower than the saturated hydraulic conductivity of the stony soil, the highest outflow is predicted in a soil with the highest stoniness and high initial water content of soil matrix. Relatively low available retention capacity in a stony soil profile and consequently higher unsaturated hydraulic conductivity leads to faster movement of the infiltration front during rainfall.
The aim of this study was to test the applicability of a simple scaling methodology for a regional estimation of intensity-duration-frequency (IDF) curves in Slovakia. The analysis is based on the regionalization process of Gaál (2006), which focused on the delineation of homogeneous regions for a regional frequency analysis of precipitation maxima. In order to examine the regionally estimated IDF curves, a region covering the western parts of Slovakia was chosen. The selected region, which encompasses 19 raingauging stations, may be characterized by the dominant influence of Atlantic circulation patterns. Three of the 19 stations belonging to the target region were set aside and flagged as verification stations. The regional dimensionless growth curve of 1-day precipitation maxima in the warm season was derived for the region, and the local T-year quantiles were estimated by the index value method for the stations. At the same time, a regionally averaged scaling exponent was derived using all the stations except for the three verification ones. The local IDF curves at the verification stations were estimated by downscaling the Tyear quantiles of the 1-day precipitation maxima using the regionally averaged scaling exponent. Finally, the IDF curves for these stations were compared with those defined by Šamaj, Valovič (1973). This study is the first step in assessing the applicability of a simple scaling theory for the regional estimation of IDF curves in Slovakia. and Cieľom tejto práce bolo otestovať možnosť použitia metódy jednoduchého škálovania zrážok pri regionálnom odhade návrhových hodnôt zrážkových intenzít na Slovensku. Pre analýzu bolo vybraných 19 zrážkomerných staníc vo vopred vyčlenenom regióne na území západného Slovenska, pričom tri stanice boli separované ako verifikačné stanice. Pre vybraný región sme odvodili bezrozmernú regionálnu čiaru prekročenia jednodenných maximálnych úhrnov zrážok v teplom polroku a následne sme pre verifikačné stanice metódou indexovej hodnoty odhadli lokálne návrhové hodnoty pre rôzne významné doby opakovania T (tzv. T-ročné kvantily). Vo vyčlenenom regióne sme určili priemerný regionálny škálovací koeficient. Návrhové zrážkové intenzity pre tri verifikačné stanice sa stanovili zoškálovaním T-ročných kvantilov jednodenných maximálnych zrážok pomocou regionálneho škálovacieho koeficientu. Určené návrhové hodnoty sme porovnali s výsledkami Šamaja, Valoviča (1973). Štúdia potvrdila možnosť využitia metódy jednoduchého škálovania na regionálny odhad návrhových hodnôt zrážkových intenzít na Slovensku.
In Tichý (1969), it is shown that semantics of natural language can be pursued procedurally. Tichý supported his argument by defining elementary functions of logic (truth functions, quantifiers) using Turing machines and attempting to define the sense of empirical expressions using a simple semantic version of oracle. From the way how Turing machines and later constructions are defined it follows that even the sense of empirical expressions can be successfully handled but that the sense and denotation can be in principle effectively obtained while the actual value at the actual world can be, of course, never computed. The present paper comments on this attempt and compares the Turing machines argument with the possibilities given by TIL constructions. Turing machines guarantee the effective character of computing while the constructions do not, but expressive power of constructions is incomparably stronger, not only because Tichý’s possible worlds from 1969 are atemporal: they define essentially 1 st order operations and can be reinterpreted as one possible world enjoying (discrete) temporal changes. Both the TM conception and the ''constructivist'' one know that the question ''which possible world is the actual one'' cannot be ever answered by effective (computational) methods and their analyses of empirical expressions are therefore compatible. and V Tichý (1969) je ukázáno, že sémantika přirozeného jazyka může být sledována procedurálně. Tichý podpořil svůj argument tím, že definoval základní funkce logiky (pravdivé funkce, kvantifikátory) za použití Turingových strojů a snažil se definovat smysl empirických výrazů pomocí jednoduché sémantické verze oracle. Ze způsobu, jakým jsou vymezeny stroje Turing a pozdější konstrukce, vyplývá, že i smysl empirických výrazů lze úspěšně zvládnout, ale smysl a denotaci lze v principu efektivně získat, zatímco skutečná hodnota v aktuálním světě může být, samozřejmě, nikdy nebyl vypočten. Tento příspěvek se k tomuto pokusu vyjadřuje a srovnává argument Turingových strojů s možnostmi danými konstrukcemi TIL. Turing stroje zaručují efektivní charakter výpočtu, zatímco konstrukce nejsou, ale expresivní síla konstrukcí je nesrovnatelně silnější, a to nejen proto, že Tichého možné světy z roku 1969 jsou atemporální: definují v podstatě operace 1. řádu a mohou být reinterpretováni jako jeden možný svět, který se těší (diskrétním) časovým změnám. Jak koncepce TM, tak konstruktivistická, vědí, že otázka ''který možný svět je skutečný'' nemůže být nikdy zodpovězena účinnými (výpočetními) metodami a jejich analýza empirických výrazů je tedy slučitelná.
Traditional depth-averaged morphodynamic models for turbidity currents usually focus on the propagation of currents after plunging. However, owing to the unsteady characteristic of the plunge point locations and the tough conditions of field measurement within the plunge zone in a reservoir, it is difficult in practice to directly provide upstream boundary conditions for these models. A one-dimensional (1D) morphodynamic model coupling open-channel flow and turbidity current in a reservoir was proposed to simulate the whole processes of turbidity current evolution, from formation and propagation to recession. The 1D governing equations adopted are applicable to open-channel flows and turbidity currents over a mobile bed with irregular cross-section geometry. The coupled solution is obtained by a two-step calculation mode which alternates the calculations of open-channel flow and turbidity current, and a plunge criterion is used to determine the location of the upstream boundary for the turbidity current, and to specify the corresponding boundary conditions. This calculation mode leads to consecutive predictions of the hydrodynamic and morphological factors, from the open-channel reach to the turbidity current reach. Turbidity current events in two laboratory experiments with different set-ups were used to test the capabilities of the proposed model, with the effect of free-surface gradient also being investigated. A field-scale application of the coupled model was conducted to simulate two turbidity current events occurring in the Sanmenxia Reservoir, and the method for calculating the limiting height of aspiration was adopted to estimate the outflow discharge after the turbidity currents arrived in front of the dam. The predicted plunge locations and arrival times at different cross-sections were in agreement with the measurements. Moreover, the calculated interface evolution processes and the sediment delivery ratios also agreed generally with the observed results. Therefore, the 1D morphodynamic model proposed herein can help to select the design capacity of the outlets, and optimize the procedure for sediment release in reservoirs.
The aim of the paper is to disclose an ontological setting of possible worlds used by Pavel Cmorej in his papers focused mainly on intensional semantics and its applications. The paper offers a range of attitudes toward possible worlds spanning from radical realism to radical eliminativism. Cmorej’s possible worlds are best understood in terms of moderate realism that sees them as objective abstract entities based on the ontology and principles of combinatorialism. However, combinatorialism doesn’t occur in its standard form because some aspects of abstractionism are present as well. and Martin Schmidt