This paper deals with studying of two topics – measuring of velocity profile deformation behind a over-flooded construction and modelling of this velocity profile deformation by computational fluid dynamics (CFD). Numerical simulations with an unsteady RANS models - Standard k-ε, Realizable k-ε, Standard k-ω and Reynolds stress models (ANSYS Fluent v.18) and experimental measurements in a laboratory flume (using ADV) were performed. Results of both approaches showed and affirmed presence of velocity profile deformation behind the obstacle, but some discrepancies between the measured and simulated values were also observed. With increasing distance from the obstacle, the differences between the simulation and the measured data increase and the results of the numerical models are no longer usable.
On the occasion of 80th birthday of an excellent Slovak philosopher Pavel Cmorej, some characteristic features of his work are presented. Cmorej is shown as a solid thinker who always took care of precisely expressing his thoughts. One of his remarkable works is a collection of his philosophical dialogues (published in 2007) where Cmorej’s analysis of various philosophical problems demonstrates his ability to develop analytic philosophy so that (the desirable) English translations of his works would certainly surprise his contemporary world analytic philosophers. and Pavel Materna
The paper deals with the paradoxes of inference and analysis. It attempts to show what is specific about these paradoxes. They have got a lot in common. Often, they are not considered paradoxes in the strict sense at all. Moreover, they both raise the same problem: How can the requirements of correctness and informativeness be both met for inference and for conceptual analysis? The strategies developed to address the problem are similar for both cases. In the paper, I claim that the paradoxes have common origins. This claim is supported by comparing different strategies adopted to resolve the problem. Regarding their origins, both paradoxes share the epistemological framework that is grounded in Aristotle’s theory of science. This is related to the problem of implicit knowledge, which is a variation on a dilemma formulated by Plato in his Meno. Aristotle’s solution to the dilemma of Meno is discussed and considered as another plausible strategy for dealing with the paradoxes of inference and analysis., Příspěvek se zabývá paradoxy odvození a analýzy. Snaží se ukázat, co je na těchto paradoxech specifické. Mají spoustu společného. Často nejsou vůbec považovány za paradoxy. Oba tyto otázky navíc vyvolávají stejný problém: Jak mohou být splněny požadavky na správnost a informativnost pro závěry a pro koncepční analýzu? Strategie vyvinuté pro řešení tohoto problému jsou podobné v obou případech. V příspěvku tvrdím, že paradoxy mají společný původ. Toto tvrzení je podpořeno porovnáním různých strategií přijatých k vyřešení problému. Pokud jde o jejich původ, oba paradoxy sdílejí epistemologický rámec, který je založen na Aristotelově teorii vědy. To souvisí s problémem implicitní znalosti, což je variace na dilema formulované Platónem v jehoMeno . Aristotelovo řešení dilematu Meno je diskutováno a považováno za další přijatelnou strategii pro řešení paradoxů odvození a analýzy., and Karel Šebela
The goal of this paper is to demonstrate that procedurally structured con- cepts are central to human communication in all cultures and throughout history. This thesis is supported by an analytical survey of three very different means of communication, namely Egyptian hieroglyphs, pictures, and Inca knot writing known as khipu. My thesis is that we learn, communicate and think by means of concepts; and regardless of the way in which the meaning of an expression is encoded, the meaning is a concept. Yet we do not define concepts within the classical set-theoretical framework. Instead, within the logical framework of Transparent Intensional Logic, we explicate concepts as logical procedures that can be assigned to expressions as their context-invariant meaning. In particular, complex meanings, which structurally match complex expressions, are complex procedures whose parts are sub-procedures. The moral suggested by the paper is this. Concepts are not flat sets; rather, they are algorithmically structured abstract procedures. Unlike sets, concepts have constituent sub-procedures that can be executed in order to arrive at the product of the procedure (if any). Not only particular parts matter, but also the way of combining these parts into one whole ''instruction'' that can be followed, understood, executed, learnt, etc., matters., Cílem příspěvku je ukázat, že procesně strukturované koncepty jsou ústředním bodem lidské komunikace ve všech kulturách a v průběhu dějin. Tato práce je podpořena analytickým průzkumem tří velmi odlišných komunikačních prostředků, konkrétně egyptských hieroglyfů, obrázků a psaní uzlů Inků známých jako khipu. Má diplomová práce je, že se učíme, komunikujeme a myslíme pomocí konceptů; a bez ohledu na způsob, jakým je význam výrazu zakódován, významem je pojem. Nedefinujeme však koncepty v rámci klasického teoretického rámce. Místo toho, v logickém rámci Transparentní Intenzionální Logiky, vysvětlujeme pojmy jako logické procedury, které mohou být přiřazeny výrazům jako jejich kontextově invariantní význam. Zejména složité významy, které strukturně odpovídají komplexním výrazům, jsou složité postupy, jejichž součástí jsou dílčí postupy. Morální návrh, který tento článek navrhl, je toto. Pojmy nejsou ploché soupravy; jsou to spíše algoritmicky strukturované abstraktní postupy. Na rozdíl od sad, koncepty mají dílčí dílčí postupy, které mohou být provedeny, aby se dospělo k produktu postupu (pokud existuje). Nezáleží jen na jednotlivých částech, ale také na způsobu spojování těchto částí do jedné ,,instrukce'', kterou lze sledovat, chápat, realizovat, učit se atd., Záleží na tom., and Marie Duží
Complete descriptions of the particle-size distribution (PSD) curve should provide more information about various soil properties as opposed to only the textural composition (sand, silt and clay (SSC) fractions). We evaluated the performance of 19 models describing PSD data of soils using a range of efficiency criteria. While different criteria produced different rankings of the models, six of the 19 models consistently performed the best. Mean errors of the six models were found to depend on the particle diameter, with larger error percentages occurring in the smaller size range. Neither SSC nor the geometric mean diameter and its standard deviation correlated significantly with the saturated hydraulic conductivity (Kfs); however, the parameters of several PSD models showed significant correlation with Kfs. Porosity, mean weight diameter of the aggregates, and bulk density also showed significant correlations with PSD model parameters. Results of this study are promising for developing more accurate pedotransfer functions.
The erosion, transport and deposition of sediments in small valley reservoirs represent a significant impact on their operations, mainly with regard to reducing the volume of their accumulation. The aim of this study is a comparison and uncertainty analysis of two modelling concepts for assessment of soil loss and sediment transport in a small agricultural catchment, with an emphasis on estimating the off-site effects of soil erosion resulted in sedimentation of a small water reservoir. The small water reservoir (polder) of Svacenicky Creek which was built in 2012, is a part of the flood protection measures in Turá Lúka and is located in the western part of Slovakia, close to the town of Myjava. The town of Myjava in recent years has been threatened by frequent floods, which have caused heavy material losses and significantly limited the quality of life of the local residents. To estimate the amount of soil loss and sediments transported from the basin, we applied two modelling concepts based on the USLE/SDR and WaTEM/SEDEM erosion models and validated the results with the actual bathymetry of the polder. The measurements were provided by a modern Autonomous Underwater Vehicle (AUV) hydrographic instrument. From the sediment data measured and the original geodetic survey of the terrain conducted at the time of the construction of the polder, we calculated changes in the storage volume of the polder during its four years of operation. The results show that in the given area, there has been a gradual clogging of the bottom of the polder caused by water erosion. We estimate that within the four years of the acceptance run, 10,494 m3 of bottom sediments on the Svacenicky Creek polder have accumulated. It therefore follows that repeated surveying of the sedimentation is very important for the management of the water reservoir.
Carbonate rocks host several large water and hydrocarbon reservoirs worldwide, some of them highly heterogeneous involving complex pore systems. Pre-salt reservoirs in the Santos Basin off the south-east coast of Brazil, are an example of such rocks, with much attention focused on proper characterization of their petrophysical and multiphase flow properties. Since it is very difficult to obtain rock samples (coquinas) from these very deep reservoirs, analogues from north-eastern Brazil are often used because of very similar geological age and petrophysical properties. We used a coquina plug from an outcrop in a quarry in northeast Brazil to perform a comprehensive set of analyses. They included Scanning Electron Microscopy (SEM), Energy-Dispersive X-ray Spectroscopy (EDS), X-ray Diffraction (XRD), and micro-computed tomography (μCT) image acquisition using a series of pixel sizes, as well as direct permeability/ porosity measurements. Some of the experimental data were collected from the plug itself, and some from a small sample of the rock slab, including thin sections. Results included the carbonate rock composition and the pore system at different scales, thus allowing us to reconstruct and model the porosity and absolute permeability of the coquina using 3D digital imaging and numerical simulations with pore network models (PNMs). The experimental and numerical data provided critical information about the well-connected pore network of the coquina, thereby facilitating improved predictions of fluid flow through the sample, with as ultimate objective to improve hydrocarbon recovery procedures.