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Processo de certificação aeronáutica civil brasileira : estudo dos impactos na competitividade da indústria nacional
(Universidade Federal de São Carlos, 2017-01-31) Camargo, Gerson Marcelo; Hoffmann, Wanda Aparecida Machado; https://lattes.cnpq.br/7609135667093837; https://lattes.cnpq.br/1694574540916027
Commercial aircrafts are understood as the safest transportation when data such as operation hours by accident or incident are analyzed. According to studies conducted by the US National Security Council (NSC), the odds of a fatal crash is about one in eleven millions – which is smaller than elevators’ fatal failures, since commercial aircrafts operate for longer distances and time. Nevertheless, in order to aircraft products reach the highest reliability levels before start flying, it is necessary they to be extensively tested, ensuring that projects, materials and production methods comply to international safety requirements. This assessment process is called Aircraft Certification and is recognized as the most complex, time and money consuming of aircraft production, particularly for the civil aviation aircrafts. In Brazil, this activity is under the accountability of a Federal Agency, which regulates an important sector of the national economy. Therefore, the main objective of the present study was to analyze the Brazilian Aircraft Certification Process and assess its possible impacts in the competitiveness of national aerospace industry. Research information is based on a wide bibliographical review, regarding certifying process and national aerospace industry, followed by a field research, conducted through semi-structured interviews focused on understanding the perceptions of big companies, small and medium enterprises (SME) and Aircraft Certification Authority on this subject. Analysis of collected data indicate the Certifying Process is not capable by itself to influence the industrial development, but the structures of the organizations evolved on the Certification Process and the lack of interest and public policies may limit the competitiveness of the national aerospace industry. Opportunities which can contribute to the organizations and to the studied processes were identified, but current circumstances lead to the conclusion that in short and medium time it is going to be very difficult to a big Brazilian aerospace company to succeed in reaching the levels of the two major global aircraft builders, as well as for the small and medium enterprises in building bigger aircrafts, following the steps of the big companies.
Estimativa da performance térmica de Cycloneda sanguinea L. (Coleoptera: Coccinelidae) utilizando modelos lineares e não lineares
(Universidade Federal de São Carlos, 2017-01-31) Pachú, Jéssica Karina da Silva; Godoy, Wesley Augusto Conde; https://lattes.cnpq.br/0147181014156799; Rossi, Fabrício; https://lattes.cnpq.br/0621862166341833; https://lattes.cnpq.br/2656204781354803
Understanding the life cycle of insects and their relation to environmental factors such as temperature is essential for the optimization of pest control programs. However, information that considers insect survival and development rates together is incipient. The assessment of these rates concomitantly may reveal the performance in terms of viability and speed of development in a given environmental condition. The insect development rate is often estimated using degree-day-based models, however, nonlinear models have been shown to be more adequate in estimating these rates because they are more realistic and still provide maximum and optimal development temperatures. Thus, the present study estimated the maximum performance of Cycloneda sanguinea L. (Coleoptera: Coccinelidae) as a function of temperature using a linear model, and described the relationship between predator developmental rates and temperature using nonlinear models. The maximum performance was estimated by derivative of the logistic equation. The best models for describing larval phase development rates at different temperatures are the Analytis and Brière models, while Sharpe & DeMichele and Brière are more suitable for the pupa stage of C. sanguinea. For males the estimated temperature that caused the maximum performance was 31°C for the 1st and 2nd instar, for the third and fourth instars the predicted temperature is 28.9 and 27.3oC, respectively. Regarding the females, the temperature that favored the maximum rate of development and survival was 31°C for the first three instars and 27°C to 4th instar. It was evidenced that besides the effect of temperature dependence the performance of the individuals varies according to stage of development and sex of the individuals. With this information it will be possible to better base the multiplication and release programs of C. sanguinea, accurately controlling the speed of development in the laboratory or even scheduling the most favorable times for its release.