Measuring evaporation and transpiration at the field scale is complicated due to the heterogeneity of the environment, with point measurements requiring upscaling and field measurements such as eddy covariance measuring only the evapotranspiration. During the summer of 2014 an eddy covariance device was used to measure the evapotranspiration of a growing maize field at the HOAL catchment. The stable isotope technique and a Lagrangian near field theory (LNF) were then utilized to partition the evapotranspiration into evaporation and transpiration, using the concentration and isotopic ratio of water vapour within the canopy. The stable isotope estimates of the daily averages of the fraction of evapotranspiration (Ft) ranged from 43.0–88.5%, with an average value of 67.5%, while with the LNF method, Ft was found to range from 52.3–91.5% with an average value of 73.5%. Two different parameterizations for the turbulent statistics were used, with both giving similar R2 values, 0.65 and 0.63 for the Raupach and Leuning parameterizations, with the Raupach version performing slightly better. The stable isotope method demonstrated itself to be a more robust method, returning larger amounts of useable data, however this is limited by the requirement of much more additional data.
This paper focuses on the theory of deduction, developed by the Czech logician Pavel Tichý. Research on deduction in Tichý’s logic is still not very advanced. Tichý’s own deduction system is a generalization of Gentzen’s natural deduction and although it is an interesting topic in itself, I’d rather focus on the theory or philosophy of deduction that motivates Tichý’s choice of deduction system. Some of Tichý’s expressions suggest that in the question of the status of the theory of deduction in logic he held the prevailing modern approach, but this contradicts the fact that most of his writings concern selected problems of logical semantics. Having introduced Tichý’s original conception of deduction, I pay attention to the so called object-conception of logic, which explains the special position of the theory of deduction in his conception., Příspěvek se zaměřuje na teorii dedukce vyvinutou českým logikem Pavlem Tichým. Výzkum o dedukci v Tichém logice stále není příliš pokročilý. Tichý vlastní dedukční systém je zobecněním Gentzenova přirozeného dedukce, a přestože je to samo o sobě zajímavé téma, raději bych se zaměřil na teorii nebo filosofii dedukce, která motivuje Tichého volbu systému odpočtu. Někteří z Tichých výrazů naznačují, že v otázce stavu teorie dedukce v logice zastával převažující moderní přístup, což však odporuje skutečnosti, že většina jeho spisů se týká vybraných problémů logické sémantiky. Po představení Tichého původní koncepce dedukce věnuji pozornost tzv. Objektové koncepci logiky, která v jeho pojetí vysvětluje zvláštní postavení teorie dedukce., and Karel Šebela
The peaks over threshold method (POT method) is an alternative to the block-maxima method for estimating return levels (these are the levels that are exceeded by a daily precipitation, resp. by a daily average discharge, only with a given small probability; in statistical language they are called high quantiles) when the studied series are not long enough. The paper compares both methods for precipitation and discharges series of Northern Moravia. It is shown how to overcome problems in the POT method caused by autocorrelation and seasonality. and Metoda špiček nad prahem může sloužit při odhadování vysokých kvantilů (to znamená takových hodnot, že je denní úhrnná srážka, respektive denní průměrný průtok, překročí jen s malou předem danou pravděpodobností). Jedná se o alternativu k metodě blokových maxim, a to zvláště tam, kde studované řady nejsou příliš dlouhé. Článek porovnává výsledky obou metod na příkladech srážkových a průtokových dat ze severní Moravy. Ukazuje dále, jak lze v metodě POT překonat problémy spojené s autokorelací a sezónností řad.
Deposition of solid particles in the stormwater sewers reduces the discharging capacity, causing inundation. A sediment invert trap (SIT) is an option that can be installed at the bottom of the stormwater sewer drain to intercept the flowing solid particles. In the present study performance of rectangular SIT were analyzed experimentally and computationally. Variation of particle trapping efficiency of rectangular SIT fitted at the bottom of the open channel flume has been studied under the interpretation of invert trap depth, flow depth, particle size, particle shape, and slot width. To predict the flow field and trap efficiency of a rectangular invert trap, 2D-VOF-DPM-CFD modelling has been carried out using ANSYS Fluent 2020 R1 software. For velocity field determination, the volume of fluid (VOF) model was used along with realizable k-є turbulence model. To predict particle trap efficiency, stochastic discrete phase model (DPM) was utilized. From experimental study and CFD modeling, it has been found that the particle trap efficiency of rectangular invert trap varied with change in the depth of invert trap, sediment size, shape factor, depth of flow and slot width. Consideration of particle shape in terms of shape factor in the modeling of solid-phase through DPM validated the CFD predicted results with those obtained experimentally with mean absolute percent error (MAPE) of 2.68%, 3.99% and 6.6% for sewer solid size ranges SS1, SS2, and SS3 respectively at all flow depths for both slot widths considered in this study.