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Forced migration and crime: evidence from the 2014 immigration wave to Russia
Shcherbov, Arsenii
2024 - English
Recent years have spurred significant migration movements, underscoring the need to understand their impacts. This study explores a widely-debated correlation between crime and migration. Specifically, I investigate the 2014 migration wave, studying the response of Russian crime rates to the influx of immigrants from Ukraine. I approximate local crime rates using court data on sentencing decisions and describe relevant migration flows with internet search activity. The application of the difference-in-differences method reveals positive effects for property crime sentencing and the heterogeneous response of violent crime sentencing. The findings of this study are policy-relevant and could prove beneficial in understanding and mitigating the effects of future migration waves.
Keywords:
crime; migration; Russia
Fulltext is available at external website.
Forced migration and crime: evidence from the 2014 immigration wave to Russia
Recent years have spurred significant migration movements, underscoring the need to understand their impacts. This study explores a widely-debated correlation between crime and migration. ...
Winning culture, winning future: the effects of early-career success on long-run performance
Trestcov, Ivan; Rakhmetova, Aizhamal
2024 - English
This paper investigates the influence of early-career environments on long-run performance. Utilizing quasi-randomness of the NBA Draft Lottery system, we isolate the impacts of initial team success, coaching experience, and the presence of a star player during a basketball player’s debut season. Our findings underscore the significant positive effects of early team wins and experienced coaches on future player performance. Surprisingly, playing alongside a star player in the first year does not show a strong influence. This study offers insights that extend beyond sports, emphasizing the lasting effects of early professional experience and mentorship on career trajectories.
Keywords:
early-career success; NBA draft lottery; long-term performance
Fulltext is available at external website.
Winning culture, winning future: the effects of early-career success on long-run performance
This paper investigates the influence of early-career environments on long-run performance. Utilizing quasi-randomness of the NBA Draft Lottery system, we isolate the impacts of initial team success, ...
Flow simulations approach for flocculation tanks
Idžakovičová, Kristýna; Bílek, Vojtěch; Haidl, Jan; Isoz, M.; Pivokonský, Martin
2024 - English
Flocculation in water treatment facilities plays a key role in the separation of colloidal inorganic and organic substances. Its optimization leads to a significant increase in its efficiency and savings of operational costs. However, it is currently based on trial-and-error experimental approaches. In this contribution, we focus on flow modeling in stirred flocculation tanks that would, after coupling with a calibrated model of particle aggregation, enable simulationbased flocculation optimization. Despite the abundance of literature on stirred tank modeling, there is no universal agreement on the methodology used to describe turbulence nor on the approach to the computational mesh creation. Consequently, there is no unified methodology for simulations and their validation. To address this, we present a best-practice methodology for economical, yet reliable flow simulations in the said device. This methodology includes the choice of the turbulence model, the approach to the design of a high quality mesh suitable for arbitrary geometries, and results evaluation. It is developed based on an extensive literature review, a multitude of flow simulations using several meshes of progressively higher quality and resolution, and various strategies to converge to steady-state flow conditions. The simulation quality indicators used here involve comparison with the experimental data on fluid velocity, stirrer power output, and flow rate through the impeller zone. Additionally, the resulting flow simulation models are compared using tracer transport simulations, hinting at their potential for coupling with particle aggregation models.
Keywords:
flocculation tank; stirring; MRF; CFD; OpenFOAM
Available in digital repository of the ASCR
Flow simulations approach for flocculation tanks
Flocculation in water treatment facilities plays a key role in the separation of colloidal inorganic and organic substances. Its optimization leads to a significant increase in its efficiency and ...
The heterogeneous consequences of reduced labor costs on firm productivity
Del Prato, F.; Zacchia, Paolo
2024 - English
We document how a reduction in labor costs led to heterogeneous effects on the total factor productivity (TFP) of manufacturing firms. Leveraging an Italian labor legislation reform and unique institutional features of the local collective bargaining system, we show that such effects vary along the TFP distribution. Relative to the counterfactual, TFP markedly declines on the left tail, which we explain via selection mechanisms, on the right, TFP mildly increases as firms are able to expand and reallocate their workforce. To guide the evaluation of welfare implications, we develop a general equilibrium model featuring firm selection and frictions in input markets.
Keywords:
labor costs; productivity; collective bargaining
Fulltext is available at external website.
The heterogeneous consequences of reduced labor costs on firm productivity
We document how a reduction in labor costs led to heterogeneous effects on the total factor productivity (TFP) of manufacturing firms. Leveraging an Italian labor legislation reform and unique ...
Growth and Phosphorus Dynamics During Tolypothrix tenuis Cultivation – a Cyanobacterium of Biotechnological Potential
Mušálková, Petra
2024 - English
Here I investigated the course of biomass growth, phosphorus uptake and changes in intracellular phosphorus content in T. tenuis in a batch cultivation. Cultivation experiment was held in multiple bubble columns during a light regime (alternating light and dark periods 16 and 8h). Thanks to this experiment I was able to obtain a growth curve of T. tenuis. The decrease of phosphorus concentration in the medium was disproportionally faster\nthan biomass growth resulting in significant oscillations of phosphorus content in the biomass, which are typical characteristics for LPU. It was also observed, that after all phosphorus was removed from the medium, the algae growth continues over time, while obviously utilizing intracellular phosphorus reserves. These findings are valuable in course of using this cyanobacterium for efficient bioremediation of eutrophic water based on phosphorus removal by targeted algae cultivation.
Available in a digital repository NRGL
Growth and Phosphorus Dynamics During Tolypothrix tenuis Cultivation – a Cyanobacterium of Biotechnological Potential
Here I investigated the course of biomass growth, phosphorus uptake and changes in intracellular phosphorus content in T. tenuis in a batch cultivation. Cultivation experiment was held in multiple ...
Influence of Material Properties and Mixing Dynamics on Heat Transport in Granular Materials
Kokavcová, Anna
2024 - English
This study evaluates the effect of rotational speed on heat transfer and analyzes particle motion at different stirrer rotational frequencies to understand how primary and secondary flows affect heat transfer efficiency. It also examines the effect of Young’s modulus on heat transfer at different agitator\noperating speeds. Key simulation parameters and their influence 33 on heat transfer efficiency are detailed to improve the reproducibility and applicability of the results.
Keywords:
granular mixing; heat transfer; DEM
Available in digital repository of the ASCR
Influence of Material Properties and Mixing Dynamics on Heat Transport in Granular Materials
This study evaluates the effect of rotational speed on heat transfer and analyzes particle motion at different stirrer rotational frequencies to understand how primary and secondary flows affect heat ...
Galloping of insulated bundled overhead line - nonlinear numerical analysis in time domain
Macháček, Michael; Hračov, Stanislav
2024 - English
Our contribution focuses on a 3D numerical nonlinear analysis of galloping in a specific bundled overhead line with ice accretion. We studied the susceptibility to this self-excited oscillation, critical onset wind speeds, and global dynamic response of a very low-tensioned line with simulated icing observed on similar real conductors. Due to the highly nonlinear mechanical behavior of such a flexible cable, we employed the Newmark integration method combined with the iterative Newton-Raphson method. We analyzed two numerical models of the overhead line loaded by the wind: one assuming nonlinearity only in the wind load, while retaining the linearity of the mechanical system itself, and the other representing a fully nonlinear system including geometrical nonlinearity. Our analysis revealed that the determined critical wind speeds for the onset of galloping are in relatively close ranges for both models. However, numerical simulations with the fully nonlinear system indicated significantly lower amplitudes of limit cycle oscillations, especially at higher wind speeds, compared to the linear model of the line. This underscores the necessity of using fully nonlinear models during the design stage of such low-tensioned aerial conductors.
Keywords:
aerial bundled conductors; wind effects; galloping; limit cycle oscillation
Available in digital repository of the ASCR
Galloping of insulated bundled overhead line - nonlinear numerical analysis in time domain
Our contribution focuses on a 3D numerical nonlinear analysis of galloping in a specific bundled overhead line with ice accretion. We studied the susceptibility to this self-excited oscillation, ...
COVID-19 and political preferences through stages of the pandemic: the case of the Czech Republic
Bičáková, Alena; Jurajda, Štěpán
2024 - English
We track the effects of the COVID-19 pandemic on political preferences through ‘high’ and ‘low’ phases of the pandemic. We ask about the effects of the health and the economic costs of the pandemic measured at both personal and municipality levels. Consistent with the literature, we estimate effects suggestive of political accountability of leaders during ‘high’ pandemic phases. However, we also find that the pandemic political accountability effects are mostly short-lived, and do not extend to the first post-pandemic elections.
Keywords:
COVID-19; political preferences; election outcomes
Fulltext is available at external website.
COVID-19 and political preferences through stages of the pandemic: the case of the Czech Republic
We track the effects of the COVID-19 pandemic on political preferences through ‘high’ and ‘low’ phases of the pandemic. We ask about the effects of the health and the economic costs of the pandemic ...
Collective vs. family remembrance: evidence from two Russian betrayals
Gharibyan, Sinara
2024 - English
Is family or collective remembrance of the distant past more powerful in shaping current behavior? To answer this question, I link two historical episodes from Armenian history separated by a century. During both World War I (WWI) and the 2020 Nagorno-Karabakh War, Russia was anticipated to provide military support to Armenia, its ally, but failed to do so. I demonstrate that the memories of the first Russian betrayal were activated after the second war. I identify family memory of the first betrayal using distinct West Armenian (Ottoman Armenian) surnames and proxy collective memory through locations renamed to commemorate lost Armenian localities during WWI. The difference-in-differences (DiD) approach shows that both family and collective remembrance negatively affect pro-Russian parties’ vote share, with all the conventional assumptions of DiD verified. Family remembrance influences behavior through traumatic recall, whereas collective remembrance operates via social capital.
Keywords:
collective memory; family remembrance; voting
Fulltext is available at external website.
Collective vs. family remembrance: evidence from two Russian betrayals
Is family or collective remembrance of the distant past more powerful in shaping current behavior? To answer this question, I link two historical episodes from Armenian history separated by a century. ...
Applicable Adaptive Discounted Fully Probabilistic Design of Decision Strategy
Molnárová, Soňa
2024 - English
The work addresses the issue of decreased utility of future rewards, referred to as discounting, while utilizing fully probabilistic design (FPD) of decision strategies. FPD obtains the optimal strategy for decision tasks using only probability distributions, which is its main asset. The standard way of solving decision tasks is provided by Markov decision processes (MDP), which FPD covers as a special case. Methods of solving discounted MDPs have already been introduced. However, the use of FPD might be advantageous when solving tasks with an unknown system model. Due to its probabilistic nature, FPD is able to obtain a more precise estimation of this model. After previously introducing discounting and system model estimation to FPD, the current work examines the effect of discounting on decision processes and its possible advantages when dealing with an unknown system model.
Keywords:
Bayesian estimation; decision making; discounting; forgetting; probabilistic strategy design; supression of aproximate modelling impact
Fulltext is available at external website.
Applicable Adaptive Discounted Fully Probabilistic Design of Decision Strategy
The work addresses the issue of decreased utility of future rewards, referred to as discounting, while utilizing fully probabilistic design (FPD) of decision strategies. FPD obtains the optimal ...
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