The vibration of the railway superstructure is mainly influenced by its quality, by the operational technical conditions, climatic phenomena and above all by the dynamic load by the pair of wheels of the rail vehicles and also by the quality of railway subgrade. Simultaneously, the dynamic parameters also depend on the speed of rail vehicles, on the arrangement of axles, their spring mounting and on the spring mounting of the body casing or on the weight acting on the axle, and last but not least, also on the quality of the running surface of the wheel tyre. The dynamic effects of sets of wagons are transferred through the rails to the rail pads below the base of the rails, then to the sleepers or bearers and fastening system, then to the ballast bed and also to the superstructure construction. This fact applies especially for turnout structures. In turnout rigidity is changed and also there is a place where the wheel passes over a gap (in case of fixed crossings). In particular of above mentioned reasons, turnout is a place where high dynamic effects occurre and that is why often defects occurre. Dissertation thesis will be focused on measurement and analysis of the dynamic effects on turnout. The point of the thesis will be updating recent system (observing of the geometrical parameters and wear of the rails in turnouts) for dynamic effect observe. Methodology of the measurement and convenient mathematical apparatus for analysing dynamic effect will be proposed.

The [2,3]-sigmatropic rearrangement is a pericyclic reaction of great synthetic utility to organic chemists. Within the scope of this reaction exist some cases in which the product corresponding to a [1,2] rearrangement is formed, despite the fact this is a forbidden process. Generally this is explained by a radical dissociation-recombination pathway; however, studies into the failure of transition state theory and the necessity to incorporate dynamic effects into mechanistic theory lead us to believe such products may arise from these phenomena. In particular, the possibility that many of these products result from an “unsymmetrical bifurcating surface” in the potential energy landscape is intriguing. To investigate this possibility, the Sommelet-Hauser rearrangement of N-allyl-N,N-dimethylglycine methyl ester was explored. The combined use of experimental and theoretically predicted kinetic isotope effects (KIEs) has been previously shown to deliver great mechanistic insight into reactions. The combination of these techniques, however, has found little employ in studying [2,3] rearrangements. This combination was used to study this reaction, using the Singleton method for determining small heavy-atom isotope effects. Resulting experimental KIEs suggest the reaction proceeds by an asynchronous, concerted, early transition state, and is relatively exothermic. This agrees with previous studies and Hammond’s postulate. Predicted theoretical KIEs are in good agreement with experimental KIEs, and the associated transition structure confirms the results suggested by experiment. Interestingly, as calculations proceed from gas phase to solvent models, the activation barrier of the reaction increases, while its exothermicity decreases. The energy difference determined between the lowest and second lowest energy transition structures decreases to 0.81 kcal/mol in the PCM model, so we cannot exclude the contribution of this transition structure to the reaction. However, qualitative results from the associated KIEs and energetics are consistent with the lowest energy transition structure. This reaction does not seem to afford the [1,2] product, and most likely dynamic effects are insignificant in determining product distribution. However, the study has validated, with respect to this body of reactions, both the use of the Singleton method for KIE determination and the combination of these experimental and theoretical techniques.

The diploma thesis concerns with the design and static analysis of the heliport steel construction, which has the height of 20 m. The heliport is situated in Prague, Na Františku as a part of the hospital. The technical report and drawings are included in the thesis as well. The thesis consists of the determination of the heliport total load (including permanent, live and climate loads) and, its implementation in the SCIA Engineer 2015.3 computer software. The stress analysis of selected rods and, joints was consequently carried out by means of the manual calculation.

This thesis is focused on measurement and analysis of dynamic effects on railway turnouts. Two same-type turnouts with different fastening elasticity were chosen. My attention was focused mainly on the crossing part of the turnout, where the highest dynamic impacts occur. The point of the thesis is comparison of the crossing part of turnouts in term of dynamic behaviour and assessment of influence of soft rail pads on spread of dynamic energy through the construction. A part of the thesis is choice of methodology of the measurement and proposal of convenient mathematical apparatus for analysing of the dynamic effects on crossings.

Nas últimas décadas, tem-se observado uma forte tendência de edificações cada vez mais altas, esbeltas e flexíveis, o que exigiu novas considerações no cálculo estrutural de edifícios, tornando a ação do vento um elemento de grande relevância nos projetos. Além disso, o denso agrupamento de edificações nos centros de grandes cidades adicionou uma variável para um fenômeno que já era complexo: devido à proximidade, um edifício passa a influenciar o campo aerodinâmico de outros, podendo provocar grandes alterações nas pressões, além de fenômenos dinâmicos difíceis de determinar por métodos analíticos. Instruções normativas, em geral, limitam-se a prédios altos com padrões arquitetônicos regulares, afastando-se da realidade dos projetos construídos na prática, que vêm exibindo geometrias cada vez mais complexas e não convencionais. Este cenário justifica a realização de extensos estudos dentro do tema em questão, a fim de que se obtenha uma melhor compreensão dos fenômenos dinâmicos envolvidos e uma orientação mais abrangente na etapa de pré-dimensionamento da estrutura. Neste contexto, a proposta desta pesquisa consiste em dois estudos de caso, de edifícios construídos no Brasil e ensaiados em túnel de vento, que possuem uma geometria similar (em formato de “V”), mas com dimensões e detalhes arquitetônicos distintos. O objetivo é o de promover uma caracterização aerodinâmica, avaliando os carregamentos atuando global e localmente, tanto para o modelo considerado isolado quanto incluindo as condições de vizinhança. Além das ações, estudou-se o espectro do vento que se aproxima, e determinou-se as funções de admitância aerodinâmica correspondentes. Em ambos os edifícios, verificou-se que a incidência do vento aproximadamente perpendicular a uma das abas corresponde a uma direção crítica em termos de efeitos dinâmicos: os espectros dos carregamentos globais se mostraram muito similares, apresentando picos pronunciados que indicam a possibilidade de desprendimento cadenciado de vórtices; as funções de admitância aerodinâmica também evidenciaram um formato muito semelhante. O estudo em questão oferece um meio de validação para estudos futuros que utilizem modelos de ensaio simplificados, além de servir de referência para uma possível revisão da norma brasileira NBR 6123/1988 – Forças devidas ao vento em edificações, contribuindo com os avanços do conhecimento relativo a efeitos dinâmicos do vento em edifícios altos e irregulares. / In the last decades we observed a strong trend in constructing buildings increasingly tall, slender and flexible, which has asked for new consideration in the structural calculus of buildings, making the wind a relevant element in the design procedures. The grouping of buildings downtown in big cities has added another variable to an already complex phenomenon: due to the proximity, a building influences in the aerodynamic field of others, leading to pressure modifications and dynamic effects hard to determine by analytical methods. Instruction codes, in general, are limited to regular tall buildings, in contrast to the reality of projects built in practice, which have been exhibiting architectonic patterns increasingly complex and unconventional. This scenario justifies extensive studies among aerodynamic of irregular tall buildings, with the purpose of acquiring a better comprehension regarding the dynamic phenomena involved and a more accurate direction on the pre-design phase. In this context, the proposal of this research consists of two case studies about buildings constructed in Brazil and tested in wind tunnel, which have a similar geometry (V-shaped) but different dimensions and architectonic details. The objective is to promote a complete aerodynamic characterization, assessing the loads acting as a whole and also locally, with both isolated and interference conditions. Besides the action, the velocity spectrum of the approaching wind and the corresponding aerodynamic admittance were studied. Either case, it was verified that the wind incidence nearly perpendicular to one of the frontal facades is a critical direction from the perspective of dynamic effects: the spectra of global loads were very similar, with a peak emerging on the graphs, which indicate the possibility of vortex shedding; the admittance function also showed a very close format. This study offers an instrument of validation for future researches that use simplified test models, besides to fit as a reference to a possible revision of the Brazilian code NBR 6123/1988 – Wind load on building structures, contributing to the knowledge advances regarding dynamic effects on irregular tall buildings.

Nas últimas décadas, tem-se observado uma forte tendência de edificações cada vez mais altas, esbeltas e flexíveis, o que exigiu novas considerações no cálculo estrutural de edifícios, tornando a ação do vento um elemento de grande relevância nos projetos. Além disso, o denso agrupamento de edificações nos centros de grandes cidades adicionou uma variável para um fenômeno que já era complexo: devido à proximidade, um edifício passa a influenciar o campo aerodinâmico de outros, podendo provocar grandes alterações nas pressões, além de fenômenos dinâmicos difíceis de determinar por métodos analíticos. Instruções normativas, em geral, limitam-se a prédios altos com padrões arquitetônicos regulares, afastando-se da realidade dos projetos construídos na prática, que vêm exibindo geometrias cada vez mais complexas e não convencionais. Este cenário justifica a realização de extensos estudos dentro do tema em questão, a fim de que se obtenha uma melhor compreensão dos fenômenos dinâmicos envolvidos e uma orientação mais abrangente na etapa de pré-dimensionamento da estrutura. Neste contexto, a proposta desta pesquisa consiste em dois estudos de caso, de edifícios construídos no Brasil e ensaiados em túnel de vento, que possuem uma geometria similar (em formato de “V”), mas com dimensões e detalhes arquitetônicos distintos. O objetivo é o de promover uma caracterização aerodinâmica, avaliando os carregamentos atuando global e localmente, tanto para o modelo considerado isolado quanto incluindo as condições de vizinhança. Além das ações, estudou-se o espectro do vento que se aproxima, e determinou-se as funções de admitância aerodinâmica correspondentes. Em ambos os edifícios, verificou-se que a incidência do vento aproximadamente perpendicular a uma das abas corresponde a uma direção crítica em termos de efeitos dinâmicos: os espectros dos carregamentos globais se mostraram muito similares, apresentando picos pronunciados que indicam a possibilidade de desprendimento cadenciado de vórtices; as funções de admitância aerodinâmica também evidenciaram um formato muito semelhante. O estudo em questão oferece um meio de validação para estudos futuros que utilizem modelos de ensaio simplificados, além de servir de referência para uma possível revisão da norma brasileira NBR 6123/1988 – Forças devidas ao vento em edificações, contribuindo com os avanços do conhecimento relativo a efeitos dinâmicos do vento em edifícios altos e irregulares. / In the last decades we observed a strong trend in constructing buildings increasingly tall, slender and flexible, which has asked for new consideration in the structural calculus of buildings, making the wind a relevant element in the design procedures. The grouping of buildings downtown in big cities has added another variable to an already complex phenomenon: due to the proximity, a building influences in the aerodynamic field of others, leading to pressure modifications and dynamic effects hard to determine by analytical methods. Instruction codes, in general, are limited to regular tall buildings, in contrast to the reality of projects built in practice, which have been exhibiting architectonic patterns increasingly complex and unconventional. This scenario justifies extensive studies among aerodynamic of irregular tall buildings, with the purpose of acquiring a better comprehension regarding the dynamic phenomena involved and a more accurate direction on the pre-design phase. In this context, the proposal of this research consists of two case studies about buildings constructed in Brazil and tested in wind tunnel, which have a similar geometry (V-shaped) but different dimensions and architectonic details. The objective is to promote a complete aerodynamic characterization, assessing the loads acting as a whole and also locally, with both isolated and interference conditions. Besides the action, the velocity spectrum of the approaching wind and the corresponding aerodynamic admittance were studied. Either case, it was verified that the wind incidence nearly perpendicular to one of the frontal facades is a critical direction from the perspective of dynamic effects: the spectra of global loads were very similar, with a peak emerging on the graphs, which indicate the possibility of vortex shedding; the admittance function also showed a very close format. This study offers an instrument of validation for future researches that use simplified test models, besides to fit as a reference to a possible revision of the Brazilian code NBR 6123/1988 – Wind load on building structures, contributing to the knowledge advances regarding dynamic effects on irregular tall buildings.

Theoretical analysis (i.e. simulation) promoted by the laboratory tests of final product is the important aspect for determination relating to choice and using the new infrastructural constituent. However, the laboratory analysis does not need to make conclusive results in some cases. At that time, it is necessary to complete the process of validation by the measurement in-situ (directly in the track section). The European legislation requires the long-term monitoring of the test constructions in this case. During this time, both the periodic monitoring of the chosen parameters and the following comparison with reference construction are recommended. The reference construction shall be inserted to the same track section and in the same time period as well as the test construction. The track gauge, the longitudinal shifts of rails vis-a-vis the sleepers, the clamping force of fastening, the rail head profile, the sleepers and the state of rail fastenings are possible to classify like the long-term monitored parameters. All these characteristics are so-called static. They are checked in time when no carriages pass through the monitored track section. However, the analysis and determination of the test construction behaviour (dynamic characteristic) are the most accurate by the moving load. Dissertation thesis is focused on measurement and analysis of the dynamic effects at the plain line. The aim of the thesis is the completion of recent system of the new track structures verification for the dynamic parameters observe. Methodology of the measurement and convenient mathematical apparatus for analysing the dynamic effects is proposed.

This thesis is focused on measurement and analysis of dynamic effects on railway turnouts. Two same-type turnouts with different fastening elasticity were chosen. My attention was focused mainly on the crossing part of the turnout, where the highest dynamic impacts occur. The point of the thesis is comparison of the crossing part of turnouts in term of dynamic behaviour and assessment of influence of soft rail pads on spread of dynamic energy through the construction. A part of the thesis is choice of methodology of the measurement and proposal of convenient mathematical apparatus for analysing of the dynamic effects on crossings.

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Essay 1 (with Oskar Nordström Skans): This paper provides field evidence on the causal impact of past successes on future performances. Since persistence in success or failure is likely to be linked through, potentially time-varying, ability it is intrinsically difficult to identify the causal effect of succeeding on the probability of performing well in the future. We therefore employ a regression discontinuity design on data from professional golf tournaments exploiting that almost equally skilled players are separated into successes and failures half-way into the tournaments (the “cut”). We show that players who (marginally) succeeded in making the cut substantially increased their performance in subsequent tournaments relative to players who (marginally) failed to make the cut. This success-effect is substantially larger when the subsequent (outcome) tournament involves more prize money. The results therefore suggest that past successes provide an important prerequisite when performing high-stakes tasks. Essay 2: Recent experimental evidence suggests that women in general are more discouraged than men by failures which potentially can explain why women, on average, are less likely than men to reach top-positions in firms. This paper provides the first quasi-experimental evidence from the field on this issue using data from all-female and all-male professional golf tournaments to see if this result can be replicated among competitive men and women. These top-performing men and women are active in an environment with multiple rounds of competition and the institutional set-up of the tournaments makes it possible to causally estimate the effect of the result in one tournament on the performance in the next. The results show that both male and female golfers respond negatively to a failure and that their responses are virtually identical. This finding suggests that women’s difficulties in reaching top-positions in firms are caused by external rather than internal barriers. Essay 3: Voting is a fundamental human right. Yet, individuals that are younger than 18 do typically not have this right since they are considered uninformed. However, recent evidence tentatively suggests that the political knowledge of youths is endogenous to the voting age. I test for the existence of such dynamic adjustments utilizing voting age discontinuities caused by Swedish laws. I employ a regression discontinuity strategy on Swedish register data to estimate the causal effect of early age voting right on political knowledge around age 18. The results do not support the existence of positive causal effects of early age voting right on political knowledge. Thus, we should not expect that 16-year-olds respond by acquiring more political knowledge if they are given the right to vote. This finding weakens the case for a lowering of the voting age from 18 to 16. Essay 4 (with Lena Hensvik): We postulate that firms’ production losses  from absence depend on the employees’ internal substitutability, incentivizing firms to keep absence low in positions with few substitutes. Using Swedish employer-employee data we show that absence is substantially lower in such positions even conditional on establishment and occupation fixed effects. The result reflects sorting on both entry and exit margins, with stronger separations responses when it was difficult to predict the absence of the employees beforehand. These findings highlight that internal substitution insures firms against production disruptions caused by absence and that absence costs are important aspects of firms’ hiring and separations decisions.