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Charakterizace Božanského pískovce: pilotní lomové testy
Kumpová, I.; Rozsypalová, I.; Vavro, Leona; Vavro, Martin; Keršner, Z.
2020 - Czech
Cíl příspěvku představuje charakterizacipískovce zlomu Božanov u Broumova,Česká republika,pomocí pilotních lomových testů. Pět zkušebních těles z jádrových vývrtůnominálního průměru 50mm a délek 100 a125mm bylo před testy opatřeno koncentrátorem napětí ve tvaru šípového vrubu a zatěžováno spožadavkem konstantního přírůstku posunu vkonfiguraci tříbodového ohybu lisemLabTest 6.250 vlaboratoři Ústavu stavebního zkušebnictví FAST VUT vBrně. Snímaných diagramů síla–posun bylo po jejich korekci využito kvyčíslení základních lomově-mechanických parametrůstudovaného pískovce: statického modulu pružnosti, lomové houževnatosti, houževnatostia specifické lomové energie. The aim of this paper is a characterization ofsandstone from Božanov quarry near Broumov, Czech Republic,by means of the pilot fracture tests. Five drill-core test specimens withnominal diameter of 50mm and lengths of 100 and 125mmwere provided by an initial chevron type notch. Specimens were loaded in the configuration of the three-point bending as a displacement driven experimentusing LabTest 6.250 equipment in the laboratory of the Institute of Building Testing, Faculty of Civil Engineering, Brno University of Technology. The load versus displacement diagrams were used to quantify the basic mechanical fracture parameters of the studied sandstone: modulus of elasticity, fracture toughness, toughness, and specific fracture energy. Keywords: Božanov sandstone; drill-core specimen; chevron notch; fracture test; load–displacement diagram Fulltext is available at external website.
Charakterizace Božanského pískovce: pilotní lomové testy

Cíl příspěvku představuje charakterizacipískovce zlomu Božanov u Broumova,Česká republika,pomocí pilotních lomových testů. Pět zkušebních těles z jádrových vývrtůnominálního průměru ...

Kumpová, I.; Rozsypalová, I.; Vavro, Leona; Vavro, Martin; Keršner, Z.
Ústav geoniky, 2020

Random response of a dynamic system under polynomial of a white noise
Náprstek, Jiří; Fischer, Cyril
2020 - English
Many types of external additive random excitation of dynamic systems admit to be modelled as a combination of powers of a Gaussian noise. Such a type of excitation produces a non-Gaussian response even if the dynamic system is linear and the excitation is additive only. Although the excitation as a whole is non-Gaussian, the problem can be transformed into the form of a linear system with an additive and multiplicative white noise excitation which _nally produces a non-Gaussian response. The general method of transformation, the respective FPK equation, basic stochastic moments of the response, and a demonstrative example are discussed. Keywords: non-Gaussian excitation; nonlinear filtering; Kronecker algebra Available at various institutes of the ASCR
Random response of a dynamic system under polynomial of a white noise

Many types of external additive random excitation of dynamic systems admit to be modelled as a combination of powers of a Gaussian noise. Such a type of excitation produces a non-Gaussian response ...

Náprstek, Jiří; Fischer, Cyril
Ústav teoretické a aplikované mechaniky, 2020

Průzkum malt románské kaple ve věži hradu Landštejn
Válek, Jan; Skružná, Olga; Kozlovcev, Petr; Frankeová, Dita; Svoboda, Milan; Ševčík, Radek; Kotková, Kristýna
2020 - Czech
V rámci průzkumu byly odebrány čtyři vzorky malt z podlahy a dva vzorky z omítek v prostoru románské kaple nacházející se ve věži na hradě Landštejn. Cílem byla charakterizace použitých surovin, stanovení jejich poměru, charakterizace porozity malt a porovnání malt z jednotlivých stavebních fází. Four samples of floor mortars and two samples of plasters were analysed as a part of the survey in the Romanesque chapel located in the tower at Landštejn Castle. The aim was to characterize used raw materials, determine their ratio, characterize the porosity of mortars and compare mortars sorted to different phases of construction. Keywords: cultural heritage; Romanesque mortars; natural hydraulic lime; renders; floor mortars Available at various institutes of the ASCR
Průzkum malt románské kaple ve věži hradu Landštejn

V rámci průzkumu byly odebrány čtyři vzorky malt z podlahy a dva vzorky z omítek v prostoru románské kaple nacházející se ve věži na hradě Landštejn. Cílem byla charakterizace použitých surovin, ...

Válek, Jan; Skružná, Olga; Kozlovcev, Petr; Frankeová, Dita; Svoboda, Milan; Ševčík, Radek; Kotková, Kristýna
Ústav teoretické a aplikované mechaniky, 2020

Výzkumná zpráva. Sps_025: Keramika B4C + 1Ti, 1800°C, 2 min
Kumpová, Ivana; Vopálenský, Michal
2020 - Czech
Cílem práce bylo ověřit možnost pozorování stukturních detailů ve vzorcích B4C - Ti keramiky s 1 % titanu na základě 3D modelů z výpočetní tomografie. V laboratoři byl touto metodou zkoumán vzorek Sps_025: Keramika B4C + 1Ti, 1800°C, 2 min, ve tvaru válce o průměru 12 mm a výšce 10 mm. The aim of the measurement was to verify the feasibility of 3D computed tomography for observing structural details in samples of B4C - Ti ceramics with 1 % of Ti. Sample designated Sps_025: Keramika B4C + 1Ti, 1800°C, 2 min, in the form a cylinder with the diameter of 12 mm and the height of 10 mm was investigated by this method. Keywords: X-ray tomography; boron carbide ceramics; characterization of microstructures Available at various institutes of the ASCR
Výzkumná zpráva. Sps_025: Keramika B4C + 1Ti, 1800°C, 2 min

Cílem práce bylo ověřit možnost pozorování stukturních detailů ve vzorcích B4C - Ti keramiky s 1 % titanu na základě 3D modelů z výpočetní tomografie. V laboratoři byl touto metodou zkoumán vzorek ...

Kumpová, Ivana; Vopálenský, Michal
Ústav teoretické a aplikované mechaniky, 2020

Large Scale Motions in Turbulent Flows
Kellnerová, Radka; Jurčáková, Klára; Procházka, Pavel P.
2019 - English
Quadrant analysis based on the Reynolds decomposition was performed on the data from turbulent boundary layer flows above variously rough surfaces. An estimation of a convective velocity for events significant in terms of momentum flux, and the statistics of a length and amplitude of the individual events, together with their spectral analysis, was performed. Based on the analyses, we were able to detect a few individual sweep and ejection events with a length longer than 6δ, which could be considered as very large scale motions (VLSM). We also identified number of events with a longitudinal dimension equal to approximately 3δ labelled as large scale motions (LSM). The analyses were executed for various Reynolds numbers. The number of detected structures increases with the momentum of the flow. Keywords: wind tunnel; large scale motion; quadrant analysis Fulltext is available at external website.
Large Scale Motions in Turbulent Flows

Quadrant analysis based on the Reynolds decomposition was performed on the data from turbulent boundary layer flows above variously rough surfaces. An estimation of a convective velocity for events ...

Kellnerová, Radka; Jurčáková, Klára; Procházka, Pavel P.
Ústav termomechaniky, 2019

Assessing Quality of Boundary Layer Flows With the Diagnostic Plot
Jurčáková, Klára; Procházka, Pavel P.; Kellnerová, Radka
2019 - English
We experimentally investigated turbulent boundary layers over 4 rough surfaces and 1 smooth surface by particle image velocimetry for a range a free stream velocities. The obtained mean velocity vertical profiles were universally scaled by roughness length z₀ and friction velocity u*, but both parameters have to be obtained from the fit of the logarithmic or composite velocity pro le to the experimental data. Diagnostic plot, which relates turbulence intensity with the mean velocity showed good collapse of different free stream velocities for each surface. It became fully universal in its modified version when the roughness function was taken into an account. We found that turbulence intensities over our surfaces are higher than any published one and that they dependent on roughness length z₀*. Keywords: wind tunnel; turbulence intensity; rough-wall; friction velocity Fulltext is available at external website.
Assessing Quality of Boundary Layer Flows With the Diagnostic Plot

We experimentally investigated turbulent boundary layers over 4 rough surfaces and 1 smooth surface by particle image velocimetry for a range a free stream velocities. The obtained mean velocity ...

Jurčáková, Klára; Procházka, Pavel P.; Kellnerová, Radka
Ústav termomechaniky, 2019

Microscopic study of multifunctional drug molecule adhesion to electronic biosensors coated with diamond and gold nanoparticles
Finsterle, T.; Pilarčíková, I.; Bláhová, I.A.; Potocký, Štěpán; Kromka, Alexander; Ukraintsev, Egor; Nepovimová, E.; Musílek, K.; Kuča, K.; Rezek, B.
2019 - English
The easy and fast detection of drug content and concentration levels is demanded in biological research as well as in clinical practice. Here we study on microscopic level how nanodiamonds and gold nanoparticles interact with a multifunctional drug molecule directly on a biosensor surface. The sensors are made of interdigitated Au electrodes coated by 5 nm hydrogenated or oxidized nanodiamonds and further combined with Au colloidal nanoparticles (size 20 nm) providing nanoscale composite (spacing 100 nm). Atomic force microscopy is employed to measure local tip-surface adhesion forces and surface topography. AFM adhesion maps show that the drug binds to all types of nanoparticles and the adhesion is also significantly influenced by the substrates on which the nanoparticles are deposited. Role of local AFM tip interaction with nanostructured surface is also discussed.\n Keywords: alzheimer drugs; biosensors; nanodiamonds; nanoparticles Fulltext is available at external website.
Microscopic study of multifunctional drug molecule adhesion to electronic biosensors coated with diamond and gold nanoparticles

The easy and fast detection of drug content and concentration levels is demanded in biological research as well as in clinical practice. Here we study on microscopic level how nanodiamonds and gold ...

Finsterle, T.; Pilarčíková, I.; Bláhová, I.A.; Potocký, Štěpán; Kromka, Alexander; Ukraintsev, Egor; Nepovimová, E.; Musílek, K.; Kuča, K.; Rezek, B.
Fyzikální ústav, 2019

Mean-Risk Optimization Problem via Scalarization, Stochastic Dominance, Empirical Estimates
Kaňková, Vlasta
2019 - English
Many economic and financial situations depend simultaneously on a random element and on a decision parameter. Mostly it is possible to influence the above mentioned situation by an optimization model depending on a probability measure. We focus on a special case of one-stage two objective stochastic “Mean-Risk problem”. Of course to determine optimal solution simultaneously with respect to the both criteria is mostly impossible. Consequently, it is necessary to employ some approaches. A few of them are known (from the literature), however two of them are very important: first of them is based on a scalarizing technique and the second one is based on the stochastic dominance. First approach has been suggested (in special case) by Markowitz, the second approach is based on the second order stochastic dominance. The last approach corresponds (under some assumptions) to partial order in the set of the utility functions.\nThe aim of the contribution is to deal with the both main above mentioned approaches. First, we repeat their properties and further we try to suggest possibility to improve the both values simultaneously with respect to the both criteria. However, we focus mainly on the case when probability characteristics has to be estimated on the data base. Keywords: Two-objective stochastic optimization problems; scalarization; stochastic dominance; empirical estimates Fulltext is available at external website.
Mean-Risk Optimization Problem via Scalarization, Stochastic Dominance, Empirical Estimates

Many economic and financial situations depend simultaneously on a random element and on a decision parameter. Mostly it is possible to influence the above mentioned situation by an optimization model ...

Kaňková, Vlasta
Ústav teorie informace a automatizace, 2019

Proceedings of the 22nd Czech-Japan Seminar on Data Analysis and Decision Making
Inuiguchi, M.; Jiroušek, Radim; Kratochvíl, Václav
2019 - English
The history of the series of the Czech-Japan seminars started in 1999. Thus, it is now more than 20 years ago when the first Czech-Japan Seminar on Data Analysis and Decision Making under Uncertainty was held in JAIST, Hokuriku. Since that time, these seminars were held in eleven splendid places in Japan, offering the Czech participants possibility to discover different parts of the Japanese islands. In reciprocity, it was the goal of the Czech partners organizing the past ten seminars to show the beauty of Czechia to Japanese colleagues, who, during the long Japan–Czech cooperation, became our close friends. This is also why the seminar has never visited one place two times. Keywords: Decision Making; Data Analysis; Uncertainty Fulltext is available at external website.
Proceedings of the 22nd Czech-Japan Seminar on Data Analysis and Decision Making

The history of the series of the Czech-Japan seminars started in 1999. Thus, it is now more than 20 years ago when the first Czech-Japan Seminar on Data Analysis and Decision Making under Uncertainty ...

Inuiguchi, M.; Jiroušek, Radim; Kratochvíl, Václav
Ústav teorie informace a automatizace, 2019

A Step towards Upper-bound of Conflict of Belief Functions based on Non-conflicting Parts
Daniel, M.; Kratochvíl, Václav
2019 - English
This study compares the size of conflict based on non-conflicting parts of belief functions $Conf$ with the sum of all multiples of bbms of disjoint focal elements of belief functions in question. In general, we make an effort to reach a simple upper bound function for $Conf$. (Nevertheless, the maximal value of conflict is, of course, equal to 1 for fully conflicting belief functions). We apply both theoretical research using the recent results on belief functions and also experimental computational approach here. Keywords: Belief functions; Dempster-Shafer theory; Uncertainty; Conflict-ing belief masses; Conflict between belief functions; Hidden conflict Fulltext is available at external website.
A Step towards Upper-bound of Conflict of Belief Functions based on Non-conflicting Parts

This study compares the size of conflict based on non-conflicting parts of belief functions $Conf$ with the sum of all multiples of bbms of disjoint focal elements of belief functions in question. In ...

Daniel, M.; Kratochvíl, Václav
Ústav teorie informace a automatizace, 2019

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