3 resultados para Controladores robustos
em Repositório Institucional da Universidade Federal do Rio Grande do Norte
Resumo:
MEDEIROS, Adelardo A. D. et al. SISAL - Um Sistema Supervisório para Elevação Artificial de Petróleo. In: Rio Oil and Gas Expo Conference, 2006, Rio de Janeiro, RJ. Anais... Rio de Janeiro, 2006.
Análise de volatilidade, integração de preços e previsibilidade para o mercado brasileiro de camarão
Resumo:
The present paper has the purpose of investigate the dynamics of the volatility structure in the shrimp prices in the Brazilian fish market. Therefore, a description of the initial aspects of the shrimp price series was made. From this information, statistics tests were made and selected univariate models to be price predictors. Then, it was verified the existence of relationship of long-term equilibrium between the Brazilian and American imported shrimp and if, confirmed the relationship, whether or not there is a causal link between these assets, considering that the two countries had presented trade relations over the years. It is presented as an exploratory research of applied nature with quantitative approach. The database was collected through direct contact with the Companhia de Entrepostos e Armazéns Gerais de São Paulo (CEAGESP) and on the official website of American import, National Marine Fisheries Service - National Oceanic and Atmospheric Administration (NMFS- NOAA). The results showed that the great variability in the active price is directly related with the gain and loss of the market agents. The price series presents a strong seasonal and biannual effect. The average structure of price of shrimp in the last 12 years was R$ 11.58 and external factors besides the production and marketing (U.S. antidumping, floods and pathologies) strongly affected the prices. Among the tested models for predicting prices of shrimp, four were selected, which through the prediction methodologies of one step forward of horizon 12, proved to be statistically more robust. It was found that there is weak evidence of long-term equilibrium between the Brazilian and American shrimp, where equivalently, was not found a causal link between them. We concluded that the dynamic pricing of commodity shrimp is strongly influenced by external productive factors and that these phenomena cause seasonal effects in the prices. There is no relationship of long-term stability between the Brazilian and American shrimp prices, but it is known that Brazil imports USA production inputs, which somehow shows some dependence productive. To the market agents, the risk of interferences of the external prices cointegrated to Brazilian is practically inexistent. Through statistical modeling is possible to minimize the risk and uncertainty embedded in the fish market, thus, the sales and marketing strategies for the Brazilian shrimp can be consolidated and widespread
Resumo:
This study is about the institutional self-evaluation in Dimension 4, "Communication with Society", from the National System of Higher Education Evaluation SINAES, mandatory for all universities in Brazil. A multiple cases study was conducted with three institutions from Rio Grande do Norte, and the goal was to know how this evaluation is made, describing the concept for the evaluation of communication proposed by them, identifying controllers or emancipator aspects, categorizing methodological procedures and discussing the difficulties reported in the communication evaluation process. Coordinators of the institutions Evaluating Committees were interviewed and data categorized by means of qualitative content analysis. It was noted characteristics of the current controller, emancipator and hybrid designs in the three institutions for evaluation of communication, revealing the lack of a theoretical corpus that transits in accordance with the systemic perspective and epistemology of complexity from SINAES. It was found that the most frequently reported difficulties in the evaluation processes of communication are in the preparation stage, especially in the definition of indicators and tools and awareness work. The weakness in planning makes their own activities in the sector of communication become targets of assessment, forming goals poorly related with broader organizational goals. It was also concluded that the technical evaluation cannot override the issues associated with the broader issue of the complexity surrounding the assessment paradigm proposed by SINAES because contradictions and imperfections are part of the evaluation process and several references are current in the literature to support this view. Finally, it is said that objectives such as transparency and behavioral changes can rely on methodologies and techniques for research on the question of the construction of meaning