[pt] Qual é o efeito de um mercado de controle corporativo mais ativo sobre a estrutura de propriedade das firmas? Nós mostramos que, em economias com severas imperfeições no mercado de crédito, empreendedores ilíquidos elevam seus blocos de controle para que, numa disputa pelo controle, os limitados recursos que dispõem sejam suficientes para derrotar as tentativas de aquisições. À medida que a restrição financeira do empreendedor se afrouxa, a ameaça de aquisições perde força e o tamanho do bloco de controle se reduz. O modelo prevê que o tamanho dos blocos de controle em carveouts deve ser menos sensível ao nível de atividade do mercado de controle do que aquele em aberturas de capital de firmas independentes. / [en] What is the effect of greater activity in the market for corporate control on firms´ ownership structure ? We show that, in economies with malfunctioning credit markets, illiquid entrepreneurs increase their blocks´ size, so that in a context for control, their limited resources suffices to defeat takeover attempts. As entrepreneur´s financial restriction is softened, the threat of takeovers dwindles and the size of the controlling blocks falls. The model predicts that sales of shares in carve-outs should be less sensitive to the level of activity in the market for control than thos in IPOs of independent firms.

The main theme of this diploma thesis is a description and a strength analysis of several steel structures of valve frames used by Bosch Rexroth, s. r. o. The first part sums up possibilities of fastening of hydraulic control elements. Furthermore, current types of valve frames were described. The strength analysis of three steel structures was output of using the finite elements method. The result of these analysis was the determination of the loads and critical points of individual structures. In the end of this study, new structures for one block frame were designed to modify the critical locations of the original solution.