No (1447)
Yes (919)
Number of found documents:
2366
Published from
to
Implementation of a plasticity model with advanced kinematic hardening rule for additively manufactured materials
Marek, René; Parma, Slavomír; Gabriel, Dušan; Džugan, J.
2023 - English
This technical report summarizes particularly the modeling part of the project DP 04_01_NPO “Emission-free technologies for local energy sources replacement” including development of models to describe multi-material 3D printed structures. The work is done in cooperation between COMTES FHT, a.s., the Institute of Thermomechanics of the Czech Academy of Sciences, v.v.i. and PROINNO, a.s. The goal of the project is the development of material models describing the behavior of multi-material components deposited by the direct deposition method (DED) under multiaxial cyclic loading.\nIn the report, a plasticity model suitable for materials prepared by the additive manufacturing method is compiled and used. The model uses Hill's plasticity condition, an advanced multi-component kinematic hardening rule, and an isotropic hardening rule. The associated flow rule is chosen and the implementation assumes the theory of small deformations. All constitutive relationships are presented and discussed for the selected model, and the model is thus fully and unambiguously formulated. The model is analytically integrated for a special case of loading and a special choice of parameters of the plasticity condition, namely transverse isotropy. A discretization scheme for numerical integration and procedures for FE implementation of the model are presented. For the FE implementation, a formulation in the displacement field is assumed, specifically the FE solver Abaqus and the implementation of the model using the UMAT interface are targeted. Several examples of the model's response to monotonic, uniaxial and biaxial cyclic loading trajectories are presented. \n Tato zpráva shrnuje postup prací na dílčím projektu DP 04_01_NPO “Emission-free technologies for local energy sources replacement” zahrnující vývoj modelů pro popis chování multi-materiálových 3D tištěných struktur řešený v konsorciu COMTES FHT, a.s., Ústav termomechaniky AV ČR, v.v.i. a PROINNO, a.s. Cílem projektu je vývoj materiálových modelů popisujících chování multi-materiálových komponent deponovaných metodou přímé depozice (DED) pří víceosém cyklickém zatěžování. \nVe zprávě je sestaven a použit model plasticity vhodný pro materiály připravené metodou aditivní výroby. Model využívá Hillovu podmínku plasticity, pokročilý vícesložkový model kinematického zpevnění a model isotropního zpevnění. Je zvolen asociovaný zákon tečení a implementace předpokládá teorii malých deformací. Pro zvolený model jsou uvedeny a diskutovány všechny konstitutivní vztahy a model je tak plně a jednoznačně formulován. Model je analyticky integrován pro speciální případ zatěžování a speciální volbu parametrů podmínky plasticity, konkrétně příčnou isotropii. Je prezentováno diskretizační schema pro numerickou integraci a procedury pro MKP implementaci modelu. U MKP implementace se předpokládá formulace v poli posunutí, konkrétně je pak cíleno na MKP řešič Abaqus a implementaci modelu pomocí rozhraní UMAT. Je prezentováno několik příkladů odezvy modelu na monotónní, jednoosé a víceosé cycklické zatěžovací trajektorie.\n
Keywords:
plasticity; anisotropy; additive manufacturing
Available at various institutes of the ASCR
Implementation of a plasticity model with advanced kinematic hardening rule for additively manufactured materials
This technical report summarizes particularly the modeling part of the project DP 04_01_NPO “Emission-free technologies for local energy sources replacement” including development of models to ...
Parental allowance increase and labour supply: evidence from a Czech reform
Grossmann, Jakub; Pertold, Filip; Šoltés, M.
2023 - English
We study the effect of a CZK 80,000 (36%) increase in parental allowance, a universal basic income-type benefit, on the labor supply of parents in the Czech Republic. Drawing a parental allowance does not preclude labor market activity, which allows us to study the income effect. After the reform, mothers substantially prolonged the average period they drew an allowance. The labor market participation of mothers of young children decreased by 6 percentage points (15%). The estimated effect corresponds to a non-labor income labor supply elasticity at the extensive margin of about -0.5. The effect is particularly strong among mothers with their first child (10 p.p. or 28%) and among university-educated mothers (16 p.p. or 36%). We observe a virtually identical reduction in hours worked. We found no effect on the labor supply of fathers.
Keywords:
parental allowance; maternal labor supply; income effect of social policy
Fulltext is available at external website.
Parental allowance increase and labour supply: evidence from a Czech reform
We study the effect of a CZK 80,000 (36%) increase in parental allowance, a universal basic income-type benefit, on the labor supply of parents in the Czech Republic. Drawing a parental allowance does ...
Voting under debtor distress
Grossmann, Jakub; Jurajda, Štěpán
2023 - English
There is growing evidence on the role of economic conditions in the recent successes of populist and extremist parties. However, little is known about the role of over-indebtedness, even though debtor distress has grown in Europe following the financial crisis. We study the unique case of the Czech Republic, where by 2017, nearly one in ten citizens had been served at least one debtor distress warrant even though the country consistently features low unemployment. Our municipality-level difference-in-differences analysis asks about the voting consequences of a rise in debtor distress following a 2001 deregulation of consumer-debt collection. We find that debtor distress has a positive effect on support for (new) extreme right and populist parties, but a negative effect on a (traditional) extreme-left party. The effects of debtor distress we uncover are robust to whether and how we control for economic hardship, the effects of debtor distress and economic hardship are of similar magnitude, but operate in opposing directions across the political spectrum.
Keywords:
debtor distress; distress warrants; populist parties
Fulltext is available at external website.
Voting under debtor distress
There is growing evidence on the role of economic conditions in the recent successes of populist and extremist parties. However, little is known about the role of over-indebtedness, even though debtor ...
The long-term impact of energy poverty and its mitigation on educational attainment: evidence from China
Martirosyan, Yervand
2023 - English
Existing studies demonstrate the short-run connection between environmental conditions and academic performance. However, the long-term effects of exposure to adverse living conditions on academic achievement remain underexplored. This study investigates the long-term impact of energy poverty, and policy interventions aimed at alleviating it, on the academic performance of Chinese schoolchildren starting from infancy. It specifically utilizes the Huai River Policy, which provides free winter heating exclusively to northern regions in China but not to adjacent southern regions. My findings suggest a significant positive influence of winter heating on schoolchildren’s academic performance, with a more pronounced effect for children born during winter months. The insights gained from this research could inform policy debates to enhance educational outcomes and human well-being.\n
Keywords:
energy poverty; academic performance; climate
Fulltext is available at external website.
The long-term impact of energy poverty and its mitigation on educational attainment: evidence from China
Existing studies demonstrate the short-run connection between environmental conditions and academic performance. However, the long-term effects of exposure to adverse living conditions on academic ...
Novel embedding resins for 3D-SEM II
Šlouf, Miroslav; Pavlova, Ewa; Strachota, Beata; Strachota, Adam; Nebesářová, Jana; Týč, Jiří; Krzyžánek, Vladislav; Skoupý, Radim
2023 - English
Research report for Thermo Fisher Scientific s. r. o., based on common project awarded by TA CR (program: National center of competence, TN01000008).
Keywords:
novel embedding resins; 3D-SEM microscopy; higher e-beam resistance
Available at various institutes of the ASCR
Novel embedding resins for 3D-SEM II
Research report for Thermo Fisher Scientific s. r. o., based on common project awarded by TA CR (program: National center of competence, TN01000008).
Are subsidies to business R&D effective? Regression discontinuity evidence from the TA CR ALFA programme
Bajgar, Matěj; Srholec, Martin
2023 - English
Governments subsidise business research and experimental development (R&D) to promote development of the economy, because externalities and information asymmetries inherent to the innovation process make private funding of these activities fall short of what is socially desirable. Nevertheless, how effective such subsidies are and whether they achieve their goals is an open question that needs to be studied empirically. This study leverages the state-of-the-art method of regression discontinuity (RD) that allows us to come very close to making causal inferences about the effects of subsidies, to find out whether the Technology Agency of the Czech Republic’s (TA CR) ALFA programme stimulated new business R&D inputs, outputs, and positive economic impacts that would not have happened otherwise.
Keywords:
government subsidies; innovations; economic development
Fulltext is available at external website.
Are subsidies to business R&D effective? Regression discontinuity evidence from the TA CR ALFA programme
Governments subsidise business research and experimental development (R&D) to promote development of the economy, because externalities and information asymmetries inherent to the innovation process ...
“Crime and punishment”? How banks anticipate and propagate global financial sanctions
Mamonov, Mikhail; Pestova, Anna; Ongena, S.
2023 - English
We study the impacts of global financial sanctions on banks and their corporate borrowers in Russia. Financial sanctions were imposed consecutively between 2014 and 2019, allowing targeted (but not-yet-sanctioned) banks to adapt their international and domestic exposures in advance. Using a staggered difference-in-differences approach with in-advance adaptation to anticipated treatment, we establish that targeted banks immediately reduced their foreign assets and actually increased their international borrowings after the first sanction announcement compared to other similar banks. We reveal that the added value of the next sanction announcements was rather limited. Despite considerable outflow of domestic private deposits, the government support prevented disorderly bank failures and resulted in credit reshuffling: the banks contracted corporate lending by 4% of GDP and increased household lending by almost the same magnitude, which mostly offset the total economic loss. Further, we introduce a two-stage treatment diffusion approach that flexibly addresses potential spillovers of the sanctions to private banks with political connections. Employing unique hand-collected board membership and bank location data, our approach shows that throughout this period, politically-connected banks were not all equally recognized as potential sanction targets. Finally, using syndicated loan data, we establish that the real negative effects of sanctions materialized only when sanctioned firms were borrowing from sanctioned banks. When borrowing from unsanctioned banks, sanctioned firms even gained in terms of employment and investment but still lost in terms of market sales pointing to a misallocation of government support.
Keywords:
staggered policy implementation; anticipation effects; treatment diffusion
Fulltext is available at external website.
“Crime and punishment”? How banks anticipate and propagate global financial sanctions
We study the impacts of global financial sanctions on banks and their corporate borrowers in Russia. Financial sanctions were imposed consecutively between 2014 and 2019, allowing targeted (but ...
Drivers of Private Equity Activity across Europe: An East-West Comparison
Kočenda, Evžen; Shivendra, R.
2023 - English
We investigate the key macroeconomic and institutional determinants of fundraising and investment activities and compare them across Europe, covering 13 Central and Eastern European (CEE) and 16 Western European (WE) countries. Five macroeconomic variables and nineteen institutional variables are selected. These variables are studied using panel data analysis with fixed effects and random effects models over an eleven-year observation period (2010–2020). Bayesian Model Averaging (BMA) is applied to select the key variables. Our results suggest that macroeconomic variables have no significant impact on fundraising and investment activity in either region. Investment activity is a significant driver of fundraising across Europe. Similarly, fundraising and divestment activity are significant drivers of investments across Europe. Institutional variables, however, affect fundraising and investment activity differently. While investment freedom has a significant effect on funds raised in the WE and CEE countries, government integrity and trade freedom are both significant determinants of investments in both European regions. In addition, the results demonstrate that, in contrast to the WE region, fundraising in the CEE region is not country specific. We investigate the key macroeconomic and institutional determinants of fundraising and investment activities and compare them across Europe, covering 13 Central and Eastern European (CEE) and 16 Western European (WE) countries. Five macroeconomic variables and nineteen institutional variables are selected. These variables are studied using panel data analysis with fixed effects and random effects models over an eleven-year observation period (2010–2020). Bayesian Model Averaging (BMA) is applied to select the key variables. Our results suggest that macroeconomic variables have no significant impact on fundraising and investment activity in either region. Investment activity is a significant driver of fundraising across Europe. Similarly, fundraising and divestment activity are significant drivers of investments across Europe. Institutional variables, however, affect fundraising and investment activity differently. While investment freedom has a significant effect on funds raised in the WE and CEE countries, government integrity and trade freedom are both significant determinants of investments in both European regions. In addition, the results demonstrate that, in contrast to the WE region, fundraising in the CEE region is not country specific.
Keywords:
Private equity; Fundraising; Investment
Fulltext is available at external website.
Drivers of Private Equity Activity across Europe: An East-West Comparison
We investigate the key macroeconomic and institutional determinants of fundraising and investment activities and compare them across Europe, covering 13 Central and Eastern European (CEE) and 16 ...
The effects of government spending in segmented labor and financial markets
Stojanović, Dušan
2023 - English
This paper develops a model with high-skilled and low-skilled workers to show the expansionary effects of government spending despite large training costs for new hires. The main idea is that a fiscal stimulus induces changes in the composition of the labor force conditional on the extent of aggregate demand pressure. A period of high aggregate demand pressure is followed by a high value of forgone output as training activity causes production disruption. In this period firms decide to hire more low-skilled workers, who constitute a cheaper part of the labor force. When aggregate demand pressure is diminished, firms switch to hiring more high-skilled workers. However, the current literature considers only high-skilled workers, who tend to increase saving in government bonds to protect against poor employment prospects. In this case, the combination of weak employment prospects and the crowding-out effects of higher lump-sum taxes and government debt on private consumption and capital investment gives rise to recessionary effects. In contrast, this paper provides a model with a more realistic labor and financial market structure and suggests that countercyclical government spending in the form of government consumption and especially government investment can be used to deal with recessions.\n
Keywords:
government spending; training cost; search and match frictions
Fulltext is available at external website.
The effects of government spending in segmented labor and financial markets
This paper develops a model with high-skilled and low-skilled workers to show the expansionary effects of government spending despite large training costs for new hires. The main idea is that a fiscal ...
Sexual-orientation discrimination and biological attributions: experimental evidence from Russia
Baghumyan, Gayane
2023 - English
Understanding what drives discriminatory behavior is important in order to identify the best strategy to combat it. In this study, I exogenously manipulate participants’ beliefs about the origins of sexual orientation by providing evidence that supports biological causes of homosexuality. I employ money allocation tasks to measure discrimination. This allows me to causally identify the impact of information on discriminatory behavior. I first document the prevalence of discrimination against individuals with same-sex partners in Russia. On average, roughly 54% of participants exhibit discriminatory behavior against profiles with same-sex partners by allocating 16 percentage points less money to them. Further, the results suggest that exposure to evidence on the biological causes of homosexuality negatively affects discriminatory behavior. Participants in the treatment group allocate less money to profiles with same-sex partners, relative to participants in the baseline group. Potential rationales for this behavior could include the following: (i) the provision of information that contradicts existing beliefs might cause cognitive dissonance, triggering irritation and intensifying discriminatory tendencies, (ii) the information might foster beliefs that individuals in same-sex partnerships are fundamentally ’other’ - even at a biological level - thereby widening the perceived social gap between participants and these sexual minority groups and fostering discrimination further.
Keywords:
discrimination; information; sexual minorities
Fulltext is available at external website.
Sexual-orientation discrimination and biological attributions: experimental evidence from Russia
Understanding what drives discriminatory behavior is important in order to identify the best strategy to combat it. In this study, I exogenously manipulate participants’ beliefs about the origins of ...
NRGL provides central access to information on grey literature produced in the Czech Republic in the fields of science, research and education. You can find more information about grey literature and NRGL at service web
Send your suggestions and comments to nusl@techlib.cz
Provider
Other bases