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Digitální platformy a BOZP
Jana, Ranglová; Lenka, Scheu
2024 - Czech
Tato příručka se zaměřuje zejména na vztah platformové práce a zajištění bezpečnosti a ochrany zdraví při práci, popisuje psychosociální zátěž pracovníků a specifická rizika, která jsou s platformovou prací spojena, a to zejména s ohledem na algoritmický způsob řízení práce. Při zpracování autorky vycházely zejména z odborné literatury, dostupných studií a průzkumů na toto téma, právních předpisů, soudních rozhodnutí a koncepčních materiálů evropských a mezinárodních institucí. Na závěr jsou uvedeny jako příklady správné praxe možné preventivní přístupy k řešení problematiky platformové práce, a to ze strany digitálních platforem, státních orgánů a institucí v podobě legislativních a nelegislativních opatření, i samotných platformových pracovníků a jejich zástupců.
Keywords:
digitální platformy; digitalizace; BOZP; digital platforms; digitalization; HSE
Available in a digital repository NRGL
Digitální platformy a BOZP
Tato příručka se zaměřuje zejména na vztah platformové práce a zajištění bezpečnosti a ochrany zdraví při práci, popisuje psychosociální zátěž pracovníků a specifická rizika, která jsou s platformovou ...
Matching to suppliers in the production network: an empirical framework
Alfaro-Ureña, A.; Zacchia, Paolo
2024 - English
This paper develops a framework for the empirical analysis of the determinants of input supplier choice on the extensive margin using firm-to-firm transaction data. Building on a theoretical model of production network formation, we characterize the assumptions that enable a transformation of the multinomial logit likelihood function from which the seller fixed effects, which encode the seller marginal costs, vanish. This transformation conditions, for each subnetwork restricted to one supplier industry, on the out-degree of sellers (a sufficient statistic for the seller fixed effect) and the in-degree of buyers (which is pinned down by technology and by “make-or-buy” decisions). This approach delivers a consistent estimator for the effect of dyadic explanatory variables, which in our model are interpreted as matching frictions, on the supplier choice probability. The estimator is easy to implement and in Monte Carlo simulations it outperforms alternatives based on group fixed effects. In an empirical application about the effect of a major Costa Rican infrastructural project on firm-to-firm connections, our approach yields estimates typically much smaller in magnitude than those from naive multinomial logit.
Keywords:
production network; supplier choice; conditional logit
Fulltext is available at external website.
Matching to suppliers in the production network: an empirical framework
This paper develops a framework for the empirical analysis of the determinants of input supplier choice on the extensive margin using firm-to-firm transaction data. Building on a theoretical model of ...
Disappearing stepping stones: technological change and career paths
Kashkarov, Daniil; Artemev, V.
2024 - English
Which career paths lead workers towards high-skilled non-routine cognitive occupations? Using PSID data, we show that, for a significant share of workers, a career path towards non-routine cognitive occupations goes through middle-skilled routine occupations, with the majority going through a subset of routine cognitive occupations. We then argue that the decline in employment in routine cognitive occupations due to routine-biased technological change can negatively affect the chances of younger cohorts joining high-skilled occupations. To test this hypothesis, we develop a structural occupational choice model that endogenously generates realistic career paths and estimate it using PSID data and job ad data from three major US outlets covering the period from 1940 to 2000. Our estimations suggest that, on average, 6% of workers ending up in non-routine cognitive occupations use routine cognitive occupations as stepping stones that allow them to maintain and accumulate human capital and experience relevant for later employment in high-skilled occupations. A fall in employment opportunities in routine cognitive occupations over the period of the most intensive routine-biased technological change led to at least 1.37 million lost high-skilled workers who got stuck in less skilled occupations.
Keywords:
routine-biased technological change; occupational choice; human capital
Fulltext is available at external website.
Disappearing stepping stones: technological change and career paths
Which career paths lead workers towards high-skilled non-routine cognitive occupations? Using PSID data, we show that, for a significant share of workers, a career path towards non-routine cognitive ...
Verification of the dynamic properties of a new model turbine wheel with free blades
Voronova, Evgeniya; Procházka, Pavel; Maturkanič, Dušan; Mekhalfia, Mohammed Lamine; Hodboď, Robert
2024 - English
The paper describes a new experimental model of turbine wheel with free blades. Verification tests were carried out using a Doppler laser vibrometer, with a focus on the equipment parameters under various conditions. The measurements were performed in the Laboratory of Rotational Laser Vibrometry originated at the Institute of Thermomechanics AS CR, v.v.i.
Keywords:
natural frequencies; vibration; blade; laser; turbine
Available at various institutes of the ASCR
Verification of the dynamic properties of a new model turbine wheel with free blades
The paper describes a new experimental model of turbine wheel with free blades. Verification tests were carried out using a Doppler laser vibrometer, with a focus on the equipment parameters under ...
Reaction Mechanisms of Psychoactive Compounds
Sokolová, Romana; Beneš, Marek; Jiroušková, Eliška; Degano, I.
2024 - English
The reaction mechanism of selected new psychoactive substances (NPS) 4-methylpentedrone and 2-(((4-ethyl-2,5-dimethoxyphenethyl)amino)methyl)phenol was investigated based on their\nelectrochemical and spectroelectrochemical properties. Both drugs were examined by means of cyclic voltammetry using diagnostic parameters for particular reaction schemes, UV/Vis, and IR\nspectroelectrochemistry. Since water participates in the redox mechanism of both studied compounds, the reaction mechanism was studied under a controlled amount of water in an\nacetonitrile environment.
Keywords:
oxidation; reduction; IR spectrochemistry
Available on request at various institutes of the ASCR
Reaction Mechanisms of Psychoactive Compounds
The reaction mechanism of selected new psychoactive substances (NPS) 4-methylpentedrone and 2-(((4-ethyl-2,5-dimethoxyphenethyl)amino)methyl)phenol was investigated based on their\nelectrochemical and ...
Spectroelectrochemical Devices for Monitoring of Intermediates and Products on Carbonbased Composite Electrodes
Vaněčková, Eva; Šikula, M.; Hrdlička, Vojtěch; Sebechlebská, Táňa; Kolivoška, Viliam
2024 - English
Spectroelectrochemistry (SEC), as an interdisciplinary field, provides us with more comprehensive information about electroactive molecules involved in charge transfer reactions. Commercially\navailable SEC cells most often have an incorporated platinum working electrode, which can limit the range of the usable potential window and, in addition, can complicate the analysis due to the\nabsorption phenomenon. In this work, we designed and manufactured two types of custom-made SEC cells employing optically transparent carbon-based working electrodes for UV-Vis monitoring of reactants and electrogenerated intermediates and products. The first SEC cell is entirely manufactured by 3D printing using fused deposition modeling (FDM) by combining optically transparent (PET) and electrically conductive (PLA-CB) filaments. The second SEC cell employs pencil graphite (PG) rods as the working electrode (PGE) and its body is manually assembled from quartz slides. The functionality of the FDM 3D printed SEC cell and manually assembled quartz SEC cell were verified by cyclic voltammetry with in situ UV-Vis spectroscopic absorption monitoring of ruthenium(III) acetylacetonate (Ru(ac)3) redox-active probe dissolved in an aqueous or non-aqueous deaerated solvent, respectively. Both presented cells enable complete redox reversible conversion and strictly oxygen-free conditions.
Keywords:
pencil graphite electrode; spectroelectrochemistry; 3D printed electrode
Available on request at various institutes of the ASCR
Spectroelectrochemical Devices for Monitoring of Intermediates and Products on Carbonbased Composite Electrodes
Spectroelectrochemistry (SEC), as an interdisciplinary field, provides us with more comprehensive information about electroactive molecules involved in charge transfer reactions. ...
Česká putování za Richardem Wagnerem
Fránek, Michal; Kopecký, J.
2024 - Czech
Studie zkoumá fenomén českých cest za slavným německým skladatelem Richardem Wagnerem a do míst spojených s jeho kultem (Mnichov, Bayreuth, Curych atd.). Zaměřuje se na wagnerovské cesty – uskutečněné i neuskutečněné – českých skladatelů (Bedřich Smetana, Antonín Dvořák, Zdeněk Fibich, Josef Bohuslav Foerster), interpretů (Ema Destinnová, Karel Burian aj.), hudebních kritiků (Otakar Hostinský, V. V. Zelený), malířů (Jaroslav Čermák) a spisovatelů (Julius Zeyer, Jaroslav Maria, Teréza Nováková), přičemž sleduje jejich různé motivace. The study explores the phenomenon of Czech travels to famous German composer Richard Wagner and to the places associated with his cult (Munich, Bayreuth, Zurich, etc.). It focuses on the Wagnerian journeys – accomplished and not – of Czech composers (Bedřich Smetana, Antonín Dvořák, Zdeněk Fibich, Josef Bohuslav Foerster), performers (Ema Destinnová, Karel Burian, etc.), music critics (Otakar Hostinský, V. V. Zelený), painters (Jaroslav Čermák) and writers (Julius Zeyer, Jaroslav Maria, Teréza Nováková), tracing their different motivations.
Keywords:
Richard Wagner; travelling to artists
Available at various institutes of the ASCR
Česká putování za Richardem Wagnerem
Studie zkoumá fenomén českých cest za slavným německým skladatelem Richardem Wagnerem a do míst spojených s jeho kultem (Mnichov, Bayreuth, Curych atd.). Zaměřuje se na wagnerovské cesty – uskutečněné ...
Basic characteristics of sulfide catalysts for the direct decomposition of H2S
Bonnet, Florian; Kaluža, Luděk
2024 - English
Sulfide catalysts are crucial in the hydrodesulfurization (HDS) of petroleum fractions, facilitating the hydrogenolysis of carbon-sulfur bonds. This process generates significant volumes of hydrogen sulfide (H2S), which is typically processed in the Claus unit. However, excess H2S can overwhelm the Claus process, creating both operational and environmental challenges. Researchers are now exploring sulfide catalysts for the direct thermo-catalytic decomposition of H2S to address this issue. Supported catalysts, like Mo/Al2O3, and commercial catalysts, considered typical monolayer-type well-dispersed catalysts, show the highest O2 uptake, ranging from 41.29 μmol/g for MoS2/Al2O3 (KLO) to 58.70 μmol/g for the commercial 715. Unsupported multilayer catalysts, such as Ni/MoWS2 (KKP), exhibit lower O2 uptake at 2.54 μmol/g, though it demonstrates high HDS activity with thiophene. Moreover, O2 uptake effectively describes the sintering of the Mo monolayer phase during the thermocatalytic reaction of H2S at 800°C. These O2 uptakes clearly correlate with the XRD patterns, where the MoS2 phase is X-ray amorphous with an O2 uptake of about 19.04 μmol/g, while the MoS2 phase in the spent catalyst shows certain crystallinity exhibiting an average particle size by Scherrer equation of about 6 nm and the O2 uptake of 1.63 μmol/g. O2 chemisorption thus serves as a valuable measure of the dispersion of Mo sulfides. The results obtain with the study of CoMo/Al2O3 (KJJ-family catalysts), highlight the correlation between the increasing amount of adsorbed O2 with the increasing nominal loading of MoO3 and the increasing rate constant of thiophene kTH. This research reveals the potential of these catalysts in hydrocarbon refining. The findings underline the connection between catalytic chemistry, process engineering, and environmental sustainability, with the objective to enhance industrial refining processes.
Keywords:
sulfide catalyst; O2 chemisorption; H2S decomposition
Available at various institutes of the ASCR
Basic characteristics of sulfide catalysts for the direct decomposition of H2S
Sulfide catalysts are crucial in the hydrodesulfurization (HDS) of petroleum fractions, facilitating the hydrogenolysis of carbon-sulfur bonds. This process generates significant volumes of hydrogen ...
Průzkum spojení kamenných bloků ozdobného „klenutíʺ průhledů cimbuří Prašné brány v Praze
Válek, Jan; Kotková, Kristýna; Kozlovcev, Petr
2024 - Czech
Průzkum napojení kamenných prvků cimbuří Prašné brány v Praze pomocí zemního radaru. Cílem je ověření existence propojovacích prvků ve styčné/ložné spáře mezi kameny „zaklenutí“ průhledů cimbuří a bočními opěrami. Interpretace radargramů ukazuje na kamenické spojky. Malta obsahuje železitou příměs. Survey of the connection of the stone elements of the Powder Tower in Prague using ground penetrating radar. The aim is to verify the existence of connecting elements with the „archingʺ of the battlements and side supports. Interpretation of the radargrams points to a stonemasonry dowels. The mortar contains an iron admixture.
Keywords:
ground penetrating radar; masonry joints; NDT survey
Available at various institutes of the ASCR
Průzkum spojení kamenných bloků ozdobného „klenutíʺ průhledů cimbuří Prašné brány v Praze
Průzkum napojení kamenných prvků cimbuří Prašné brány v Praze pomocí zemního radaru. Cílem je ověření existence propojovacích prvků ve styčné/ložné spáře mezi kameny „zaklenutí“ průhledů cimbuří a ...
Hlupák, hňup, ťulpas a jiní
Karlíková, Helena
2024 - Czech
Keywords:
Old Czech; etymology
Available at various institutes of the ASCR
Hlupák, hňup, ťulpas a jiní
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