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Recepção das imagens da periferia no cinema brasileiro contemporâneo por alunos de uma escola pública na periferia da cidade de São Carlos
(Universidade Federal de São Carlos, 2010-08-25) Costa, Paulo Roberto da; Pellegrini, Tânia; https://lattes.cnpq.br/0280434883580627; https://lattes.cnpq.br/3368537857766619
Estratégias familiares e sustentabilidade econômica em assentamento rural
(Universidade Federal de São Carlos, 2010-08-25) Gaspari, Luciane Cristina de; Beskow, Paulo Roberto; https://lattes.cnpq.br/5370208348544496; https://lattes.cnpq.br/4857503984068571
The economic sustainability of family farms is a major factor in promoting sustainable development in areas of rural settlements. Thus, this study sought to identify systemic approach through what are the strategies of the families who work together for the perpetuation of the familiar form of land use in order to encourage them through public policies. As economic indicators we used the value-added and value added per worker, considering the relevant aspects of establishments such as family characteristics, socioeconomic, cultural and quality of life, work organization and production, productive infrastructure, level dependence, reproductive strategies and future expectations, and the commercialization of products. Among the strategies studied the agricultural income of family farms that sell to the agricultural industry has the best performance, however the dependency and risk are high, which can lead to economic sustainability. Already in establishments that do not trade with agro farm income is lower, but is more likely to persist over time. Among these establishments, farm products that drains directly is more advantageous from the perspective of agricultural income and consumption. This reaffirms the idea that the creation of sites for the direct marketing cooperation for sustainable development in the field with decent living conditions.
Proposta de solução de problemas de scheduling considerando possibilidade de terceirização usando a técnica de otimização por colônia de formigas
(Universidade Federal de São Carlos, 2010-08-25) Tavares Neto, Roberto Fernandes; Godinho Filho, Moacir; https://lattes.cnpq.br/6136685270563354; https://lattes.cnpq.br/6954662222457389
Althought the scheduling-related literature has a high level of diversity, just a small group have been considering the possibility of outsource a set of tasks. During a literature review, only two papers related to this theme were found, both dealing on scheduling projects with outsource possibilities on single-machine environments. Along with this scenario, it was possible to stablish the ACO (Ant Colony Optimization) algorithm as a promissing tecnique to solve combinatorial problems, including scheduling problems. This thesis approaches two scheduling problems with outsourcing allowed: (i) a scheduling problem in single machine manufacturing environment and (ii) a scheduling problem in a flowshop environment. For each problem, a new ACO algorithm is proposed and implemented. To verify the quality of the results, are also proposed and implemented: (i) a mathemetical programming model for the single machine environment problem; (ii) a branch and bound algorithm for the single machine environment problem and (iii) a a mathemetical programming model for the flowshop environment problem. The results shown that both ACO algorithms generate close-to-optimal results in a shorter computational time. In the case of the single machine environment problem, the presented results are best than the results related on the literature.
Desenvolvimento de procedimentos para análise inorgânica de biodiesel usando técnicas espectroanalíticas
(Universidade Federal de São Carlos, 2010-08-25) Amais, Renata Stábile; Nóbrega, Joaquim de Araújo; https://lattes.cnpq.br/8833989058164529; https://lattes.cnpq.br/7317673960456628
In this work, analytical procedures are proposed for the determination of major and trace elements in biodiesel samples employing flame atomic absorption spectrometry (F AAS), inductively coupled plasma optical emission spectrometry (ICP OES) and inductively coupled plasma mass spectrometry (ICP-MS). Biodiesel samples used in this work were produced from different oleaginous sources (African palm, castor beans, palm, soybeans and an unknown oleaginous). Samples were prepared as microemulsion composed of biodiesel, Triton X-100, HNO3 20 % (v v-1) and n-propanol in the following proportion, 10:5:5:80 (v v-1), respectively. Calcium, Mg and Zn determinations were carried out by F AAS and two nebulization strategies were evaluated, conventional continuous nebulization (CN) and discrete aspiration (DA). Relative standard deviations (RSD) using DA were lower than 4.0, 2.2 and 5.7 % (n = 10) for Ca, Mg, and Zn, respectively. Matrix effects were evaluated by standard additions methods and external calibration using mineral oil to simulate the matrix of biodiesel and inorganic standards. The accuracy of the procedure was checked using addition and recovery experiments for different biodiesel samples and recoveries ranged from 90.8 to 115 %. Moreover, sensitivities reached by using DA for Ca, Mg and Zn were 2.5, 6.1, and 7.0-fold higher, respectively, than those obtained when employing CN. The introduction of microemulsions in ICP OES for Ca, Mg, Na, K, P, and S determinations and the use of oxygen in the composition of auxiliary gas of the plasma to avoid and/or correct matrix effects caused by the high carbon load due to the introduction of biodiesel microemulsions were evaluated. The oxygen gas and nebulization gas flow rates were optimized by measuring intensity signals and signalto- background ratio (SBR) and were fixed at 0.16 and 0.70 L min-1, respectively. Figures of merit were investigated and a good linear correlation was observed (r > 0.99) for different emission lines monitored. The accuracy was evaluated by addition and recovery experiments using different biodiesel samples by monitoring different emission lines and recoveries ranged from 103.3 to 117.5, 93.5 to 113.5, 76.3 to 92.5 and 93.3 to 116.1 % for Ca, Mg, P and S, respectively. The determinations of Na and K were not accurate probably due to the high carbon load content of microemulsions and the high background-signals in the vicinities of their emission lines. xiii Finally, the determination of trace elements in biodiesel samples (Cd, Co, Cu, Mn, Ni, Pb, Ti, and Zn) employing ICP-MS and microemulsions was evaluated. Analogously to the developed procedure using ICP OES, the addition of oxygen gas to the composition of auxiliary gas of the plasma was evaluated and proper performance was attained at 37.5 mL min-1, 4.4-fold lower than the flow rate optimized for ICP OES measurements. Limits of detection employing oxygen gas in the composition of the plasma were higher than without using it, as well as the sensitivities (slopes of analytical calibration curves) were lower when oxygen gas was added to the plasma, probably due to the highest formation of oxides. However, despite oxides formation best accuracies were reached when employing oxygen gas.