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Občané o situaci na Ukrajině – červen/červenec 2023
Červenka, Jan
2023 - Czech
V šetření, jež probíhalo v průběhu června a července 2023, Centrum pro výzkum veřejného mínění dotazovalo sadu otázek týkajících se konfliktu na Ukrajině. Výzkum zjišťoval, zda se lidé zajímají o vývoj situace na Ukrajině a zda ji pokládají za bezpečnostní hrozbu pro Českou republiku, Evropu a mír ve světě, jak se občané staví ke krokům vlády na podporu Ukrajiny a jak vidí možná opatření ze strany mezinárodního společenství.\n\nV současnosti se o vývoj situace na Ukrajině zajímají tři pětiny (60 %) české veřejnosti, což je o 18 procentních bodů méně než na jaře 2022. V dlouhodobém srovnání od roku 2014 jde o třetí nejvyšší podíl, když druhý nejvyšší byl, zaznamenám v březnu 2014.\n\nTři čtvrtiny (75 %) občanů považují situaci na Ukrajině za hrozbu pro evropskou bezpečnost, sedm desetin (70 %) ji má za hrozbu pro bezpečnost České republiky a více než dvě třetiny (68 %) situaci na Ukrajině vidí jako hrozbu pro mír ve světě.\n\nVíce než dvě pětiny občanů (43 %) souhlasí s kroky vlády na podporu Ukrajiny, nadpoloviční většina (54 %) s nimi nesouhlasí. Necelé dvě pětiny (39 %) českých občanů si myslí, že česká vláda Ukrajinu podporuje přiměřeně, jen malá část dotázaných uvedla, že ji podporuje příliš málo (2 %), a více než polovina (56 %) soudí, že ji podporuje příliš mnoho.\n\nVýrazná většina občanů souhlasí s vyvíjení diplomatického tlaku na Rusko ze strany mezinárodního společenství (72 %), o málo více než polovina (52 %) by souhlasila s úplnou politickou a ekonomickou izolací Ruska. Necelá polovina Čechů schvaluje finanční pomoc (49 %) a poskytování vojenského vybavení Ukrajině (47 %), ale jen o málo více než desetina (12 %) by podporovala vyslání vojáků, kteří by se zapojili do boje. In a survey conducted during June and July 2023, the Center for Public Opinion Research asked a set of questions about the conflict in Ukraine. The research sought to find out whether people are interested in the development of the situation in Ukraine and whether they consider it to be a security threat to the Czech Republic, Europe and world peace, how citizens feel about the government's actions in support of Ukraine and how they assess possible measures by the international community. Keywords: public opinion; Ukraine; situation; conflict; interest; security threat; peace; support Fulltext is available at external website.
Občané o situaci na Ukrajině – červen/červenec 2023

V šetření, jež probíhalo v průběhu června a července 2023, Centrum pro výzkum veřejného mínění dotazovalo sadu otázek týkajících se konfliktu na Ukrajině. Výzkum zjišťoval, zda se lidé zajímají o ...

Červenka, Jan
Sociologický ústav, 2023

On the development of a numerical model for the simulation of air flow in the human airways
Lancmanová, Anna; Bodnár, Tomáš; Sequeira, A.
2023 - English
This contribution reports on an ongoing study focusing on reduced order models for incompressible viscous fluid flow in two dimensional channels. A finite difference solver was developed using a simple implementation of the immersed boundary method to represent the channel geometry. The solver was validated for unsteady flow by comparing the obtained two-dimensional numerical solutions with analytical profiles computed from the Womersley solution. Finally the 2D model was coupled to a simple 1D extension simulating the flow in axisymmetric elastic vessel (tube). Some of the coupling principles and implementation issues are discussed in detail. Keywords: reduced order model; incompressible Navier-Stokes equations; finite difference approximation; coupling method Available in digital repository of the ASCR
On the development of a numerical model for the simulation of air flow in the human airways

This contribution reports on an ongoing study focusing on reduced order models for incompressible viscous fluid flow in two dimensional channels. A finite difference solver was developed using a ...

Lancmanová, Anna; Bodnár, Tomáš; Sequeira, A.
Matematický ústav, 2023

Simulating particle-laden flows: from immersed boundaries towards model order reduction
Isoz, Martin; Kubíčková, Lucie; Kotouč Šourek, M.; Studeník, Ondřej; Kovárnová, A.
2023 - English
Particle-laden flow is prevalent both in nature and in industry. Its appearance ranges from the trans-port of riverbed sediments towards the magma flow, from the deposition of catalytic material inside particulate matter filters in automotive exhaust gas aftertreatment towards the slurry transport in dredging operations. In this contribution, we focus on the particle-resolved direct numerical simulation (PR-DNS) of the particle-laden flow. Such a simulation combines the standard Eulerian approach to computational fluid dynamics (CFD) with inclusion of particles via a variant of the immersed boundary method (IBM) and tracking of the particles movement using a discrete element method (DEM). Provided the used DEM allows for collisions of arbitrarily shaped particles, PR-DNS is based (almost) entirely on first principles, and as such it is a truly high-fidelity model. The downside of PR-DNS is its immense computational cost. In this work, we focus on three possibilities of alleviating the computational cost of PR-DNS: (i) replacing PR-DNS by PR-LES or PR-RANS, while the latter requires combining IBM with wall functions, (ii) improving efficiency of DEM contact solution via adaptively refined virtual mesh, and (iii) developing a method of model order reduction specifically tailored to PR-DNS of particle-laden flows. Keywords: particle-laden flow; CFD-DEM; arbitrarily-shaped particles; finite volume method Fulltext is available at external website.
Simulating particle-laden flows: from immersed boundaries towards model order reduction

Particle-laden flow is prevalent both in nature and in industry. Its appearance ranges from the trans-port of riverbed sediments towards the magma flow, from the deposition of catalytic material ...

Isoz, Martin; Kubíčková, Lucie; Kotouč Šourek, M.; Studeník, Ondřej; Kovárnová, A.
Ústav termomechaniky, 2023

On Reynolds-averaged turbulence modeling with immersed boundary method
Kubíčková, Lucie; Isoz, Martin
2023 - English
The immersed boundary (IB) method is an approach in the computational fluid dynamics in which complex geometry conforming meshes are replaced by simple ones and the true simulated geometry is projected onto the simple mesh by a scalar field and adjustment of governing equations. Such an approach is particularly advantageous in topology optimizations (TO) where it allows for substantial speed-up since a single mesh can be used for all the tested topologies. In our previous work, we linked our custom IB variant, the hybrid fictitious domain-immersed boundary method (HFDIB), with a TO framework and successfully carried out an optimization under laminar flow conditions. However, to allow for optimizations of reallife components, the IB approach needs to be coupled with an affordable turbulence modeling. In this contribution, we focus on extending the HFDIB approach by the possibility to perform Reynolds-averaged simulations (RAS). In particular, we implemented the k − ω turbulence model and wall functions for closure variables and velocity. Keywords: immersed boundary; RAS; wall functions; CFD; OpenFOAM Fulltext is available at external website.
On Reynolds-averaged turbulence modeling with immersed boundary method

The immersed boundary (IB) method is an approach in the computational fluid dynamics in which complex geometry conforming meshes are replaced by simple ones and the true simulated geometry is ...

Kubíčková, Lucie; Isoz, Martin
Ústav termomechaniky, 2023

Finite element modal analysis of a silicone vocal fold filled with fluid
Hájek, P.; Radolf, Vojtěch; Horáček, Jaromír; Švec, J. G.
2023 - English
A three dimensional (3D) finite element (FE) model of a silicone vocal fold (VF) filled with fluid is presented here. The silicone part of the model is based on partial differential equations of the continuum mechanics and consider large deformations. The fluid domain encapsulated in the silicone VF is defined semianalytically as a lumped-element model describing the fluid in hydrostatic conditions. The elongated and pressurized silicone VF was subjected to perturbed modal analysis. Results showed that the choice of the fluid inside the VF substantially influences the natural frequencies. Namely, the water-filling lowers the natural frequencies approximately by half over the air-filling. Besides, the procedure of reverse engineering for obtaining the geometry of the VF from already 3D-printed mold is introduced. Keywords: perturbed modal analysis; finite element method; vocal folds; reverse engineering; biomechanics of voice Fulltext is available at external website.
Finite element modal analysis of a silicone vocal fold filled with fluid

A three dimensional (3D) finite element (FE) model of a silicone vocal fold (VF) filled with fluid is presented here. The silicone part of the model is based on partial differential equations of the ...

Hájek, P.; Radolf, Vojtěch; Horáček, Jaromír; Švec, J. G.
Ústav termomechaniky, 2023

Key barriers, opportunities and good practices for entrepreneurship and innovation
Křížková, Alena; Marková Volejníčková, Romana; Pospíšilová, Marie; Vohlídalová, Marta
2023 - English
The report is focused on barriers, opportunities and good practices for gender-sensitive innovations and entrepreneurship. It is based on the analysis of 36 interviews with experts from the health, green and digital fields and the target groups defined in the quadruple helix of academia, citizens, industry, and government. The interviews were collected by 12 GILL partners in the 10 consortium countries in 2023. Gender stereotypical cultural beliefs and norms, masculine bias, gender segregation, lack of funding, lack of policies to support work-life balance and lack of political will and empirical evidence to remove these barriers are the main problems identified. The opportunities reflected largely correspond to these barriers and highlight the role of key actors, such as the EU, in setting standards. Projects focusing on fixing the number of women under-represented in certain fields and occupations and management positions predominate among good practices. Keywords: .gender equality; gender in entrepreneurship; gender in science; gender in innovation; gender stereotypes; good practices Available in digital repository of the ASCR
Key barriers, opportunities and good practices for entrepreneurship and innovation

The report is focused on barriers, opportunities and good practices for gender-sensitive innovations and entrepreneurship. It is based on the analysis of 36 interviews with experts from the health, ...

Křížková, Alena; Marková Volejníčková, Romana; Pospíšilová, Marie; Vohlídalová, Marta
Sociologický ústav, 2023

Proměny interpretace hudebního folkloru: od ochrany každodenní kultury po vznik hudebního žánru (na příkladu České republiky)
Uhlíková, Lucie; Pavlicová, M.
2023 - Czech
Od 60. let 20. století se v české etnologii začaly rozvíjet snahy, které postupně začaly zařazovat projevy folkloru v jejich druhé existenci do odborného výzkumu. Oblast folklorismu se někdy překrývala s existujícími lidovými tradicemi, někdy na ně navazovala a někdy se jimi pouze v různé míře inspirovala. Rozlišení v takto vymezených kategoriích nebylo snadné ani v minulosti a s příchodem stále rychlejším vývojem společnosti se v obecném povědomí rozostřilo. V tomto rámci vznikl současný široký hudební žánr zakořeněný v hudebním folkloru, který není snadné obsahově vymezit. Příspěvek nastiňuje průběh jeho historického formování, ukazuje modelové momenty jeho vývoje a zabývá se jeho polyfunkčností: mnoho kolektivů se prezentuje nejen na jevišti (spolu s tanečníky) a v hudebních pořadech. koncertním prostředí (samostatně), podílí se ale také na místních etnokulturních tradicích, tanečních zábavách, rodinných oslavách (svatby, narozeniny) a komerčně zaměřených akcích. akce. K ilustraci popsaných faktů článek využívá archivní pramenný materiál a terénní výzkum založený na základě rozhovorů s vybranými hudebníky From the 1960s onwards, efforts began to develop in Czech ethnology, which gradually began to include folklore manifestations in their second existence in professional research. The field of folklorism sometimes overlapped with the existence of folk traditions, sometimes built on them, and sometimes was only inspired by them to varying degrees. The distinction in such defined categories was not easy even in the past, and with the increasingly rapid development of society, it became blurred in the general consciousness. Within this scope, a contemporary broad music genre, music folklore, has emerged that is not easy to define in terms of content. In this paper, the authors outline its historical formation, show model moments of its development, and deal with its polyfunctionality: many collectives present themselves not only on stage (together with dancers) and in concert settings (independently), but also participate in local ethno-cultural traditions, dance parties, family celebrations (weddings, birthdays), and commercially focused events. To illustrate this, the paper uses archival source material, and field research based on interviews with selected musicians. Keywords: Music folklore; transformations of folk tradition; music genre; folk revivalism in the Czech Republic Fulltext is available at external website.
Proměny interpretace hudebního folkloru: od ochrany každodenní kultury po vznik hudebního žánru (na příkladu České republiky)

Od 60. let 20. století se v české etnologii začaly rozvíjet snahy, které postupně začaly zařazovat projevy folkloru v jejich druhé existenci do odborného výzkumu. Oblast folklorismu se někdy ...

Uhlíková, Lucie; Pavlicová, M.
Etnologický ústav, 2023

From John Graunt to Adolphe Quetelet: on the Origins Of Demography
Kalina, Jan
2023 - English
John Graunt (1620-1674) and Adolphe Quetelet (1796-1874) were two important personalities, who contributed to the origins of demography. As they both developed statistical techniques for the analysis of demographic data, they are important also from the point of view of history of statistics. The contributions of both Graunt and Quetelet especially to the development of mortality tables and models are recalled in this paper. Already from the 17th century, the available mortality tables were exploited for computing life annuities. Also the contribution of selected personalities inspired by Graunt are recalled here, the work of Christian Huygens, Jacob Bernoulli, or Abraham de Moivre is discussed to document that the historical development of statistics and probability theory was connected with the development of demography. Keywords: history of demography; history of statistics; probability theory; moral statistics; mortality tables Fulltext is available at external website.
From John Graunt to Adolphe Quetelet: on the Origins Of Demography

John Graunt (1620-1674) and Adolphe Quetelet (1796-1874) were two important personalities, who contributed to the origins of demography. As they both developed statistical techniques for the analysis ...

Kalina, Jan
Ústav informatiky, 2023

MAD UFOs: Magnetically Arrested Discs with persistent Ultra-Fast Outflows
Suková, Petra; Zajaček, M.; Karas, Vladimír
2023 - English
We study an outflow that develops in the MAD state in 3D GRMHD simulations. We show that the outflow can be accelerated to\nrelativistic velocities and persist over the course of our simulation. We compare the properties of the outflow from MAD discs with those launched by orbiting secondary at close orbit. The main difference is that the orbiting body launches a more coherent, quasiperiodic ultrafast outflow at lower velocities (v < 0.5c) while the outflow launched in the MAD state (without the body) has a stochastic behaviour and has anapproximately flat velocity distribution between lower anf higher outflow velocities, 0.2c < v < 0.3c and v > 0.5c. Keywords: accretion discs; black holes; active galactic nuclei Fulltext is available at external website.
MAD UFOs: Magnetically Arrested Discs with persistent Ultra-Fast Outflows

We study an outflow that develops in the MAD state in 3D GRMHD simulations. We show that the outflow can be accelerated to\nrelativistic velocities and persist over the course of our simulation. We ...

Suková, Petra; Zajaček, M.; Karas, Vladimír
Astronomický ústav, 2023

TESTING THE METHOD OF MULTIPLE SCALES AND THE AVERAGING PRINCIPLE FOR MODEL PARAMETER ESTIMATION OF QUASIPERIODIC TWO TIME-SCALE MODELS
Papáček, Štěpán; Matonoha, Ctirad
2023 - English
Some dynamical systems are characterized by more than one timescale, e.g. two well separated time-scales are typical for quasiperiodic systems. The aim of this paper is to show how singular perturbation methods based on the slow-fast decomposition can serve for an enhanced parameter estimation when the slowly changing features are rigorously treated. Although the ultimate goal is to reduce the standard error for the estimated parameters, here we test two methods for numerical approximations of the solution of associated forward problem: (i) the multiple time-scales method, and (ii) the method of averaging. On a case study, being an under-damped harmonic oscillator containing two state variables and two parameters, the method of averaging gives well (theoretically predicted) results, while the use of multiple time-scales method is not suitable for our purposes. Keywords: Dynamical system; Singular perturbation; Averaging; Parameter estimation; Slow-fast decomposition; Damped oscillations Fulltext is available at external website.
TESTING THE METHOD OF MULTIPLE SCALES AND THE AVERAGING PRINCIPLE FOR MODEL PARAMETER ESTIMATION OF QUASIPERIODIC TWO TIME-SCALE MODELS

Some dynamical systems are characterized by more than one timescale, e.g. two well separated time-scales are typical for quasiperiodic systems. The aim of this paper is to show how singular ...

Papáček, Štěpán; Matonoha, Ctirad
Ústav teorie informace a automatizace, 2023

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