http://dx.doi.org/10.5007/2175-7968.2016v36n3p330Rsenha da obra:Cesco, Andréa; Abes, Gilles Jean; Bergmann, Juliana CristinaFaggion (Orgs.). Tradução Literária: Veredas e desafios. SãoPaulo: Rafael Copetti, 2016, 137 p.

ResumoEste trabalho apresenta uma análise da evolução da eficiência de escala de operadores logísticos frigorificados que operaram no mercado brasileiro no período de 2007 a 2010. O estudo faz uso de Análise Envoltória de Dados e procedimentos estatísticos fundamentados na análise de componentes principais para seleção das variáveis input e output utilizadas na análise. Para a elaboração do estudo foram empregados dados secundários extraídos de uma publicação especializada da área de Logística. Os resultados mostram que o setor apresentou taxa de crescimento elevado e que as empresas acompanharam esta tendência. Retornos decrescentes de escala não foram observados na amostra considerada, o que sugere que o mercado apresentava potenciais de crescimento de escala ainda inexplorados pelos operadores logísticos frigorificados. O trabalho ainda apresenta análises da evolução dos escores de eficiências com eventos anuais relacionados à alteração do porte de três empresas emblemáticas que operaram no setor. Palavras-Chaves:Eficiência de Escala, Análise de Envelopamento de Dados; Operadores Logísticos Frigorificados. Abstract This paper presents an analysis of the evolution of temperature-controlled logistics operators scale efficiency that operated from 2007 to 2010 in the Brazilian market. The study uses data envelopment analysis and statistical techniques based on principal component analysis for the selection of input variables and output used in the analysis. To develop this study secondary data taken from a specialized publication of the Logistics area were used. The results show that the sector had high growth rate and that companies size followed this trend. Decreasing returns to scale were not observed in this sample which suggests that the market have had potential scale growth untapped by the logistics service firms that operated in cold supply chains in the years considered in this study. The work also presents an analysis of the evolution of scale efficiency scores with annual events related to change the size of three flagship companies.

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Complex space missions involving large angle maneuvers and rapid attitude control, require new non-linear control techniques to design the Satellite Control System (SCS) in order to have reliability and adequate performance. In that context, one investigates a new SCS technique based on the State Dependent Riccati Equation (SDRE) methodology which can be considered as an adaptive form of the Linear Quadratic Regulator (LQR) but which allows to deal with the non linearities of the system. A nonlinear mathematical model of a flexible rotatory beam is built through the Lagrangian formulation where the flexible displacement is modelled using the assumed modes theory and a structural damping is added applying the Rayleigh technique. The SDRE controller objectives are to control the hub angular position and simultaneously to damp the flexible displacements. A computational procedure is developed which allows drawing a performance map of the system showing all SDRE reachable performances. Using this control algorithm one can obtain the Pareto's border representing the set of optimal performances. On the other hand, analyzing the influence of the weight matrixes terms, it is shown that it is possible to get the Pareto's border performances using only a few terms of the SDRE weight matrixes. On the basis of this analysis, a control law enabling to get weight matrixes' values as a function of a required performance is developed. Last of all, state dependent weight matrixes are used to show that they can improve the system performance. Based on the results, it turned out that the SDRE's performance is better than the LQR's one, not only because it can deal with non linearities, but also because its design is more flexible and permits to control the rigid-flexible satellite in the same time interval and spending less energy.