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Programação das frentes de colheita de cana-de-açúcar: uma modelagem visando o equilíbrio das capacidades de colheita e transporte
(Universidade Federal de São Carlos, 2014-06-09) Junqueira, Rogério de Ávila Ribeiro; Morabito Neto, Reinaldo
The production of sugar, ethanol and electricity from sugar cane necessarily involves harvesting and transportation of raw materials, which are expensive and complex operations and have significant influence on the quality of the industrial raw material. The literature reports several optimization approaches related to the planning of planting, harvesting and transporting of sugarcane, however the scheduling of harvesting fronts is underexplored. This thesis intends to contribute to the state-of-art of this important issue in the context of the Brazilian agribusiness. Optimization approaches to support scheduling decisions of harvesting fronts considering the balance of harvesting and transportation capacities, as well as good agronomic management are proposed. The approaches are inspired by the representation of the problem as a lot sizing and scheduling model with parallel machines and sequence-dependent setup costs and times, a modelling technique well studied in the production planning and control literature. Three variants of this formulation, based on mathematical programming models, were developed and tested in two real case studies of medium size sugar mills. Heuristic methods based on aggregation procedures and mathematical programming have also been studied and developed to solve large scaled problems found in practice. Among the three variants studied, one presented the best solution quality within the expected execution time. Important scenario analysis were done indicating that the schedule s fulfilment provides reduction of harvesting and transporting complexity to the following season, which can generate significant saves in the cases studied. Besides that, comparing the proposed scheduling method with one of the sector s practice, it can be generated also significant cost reduction in the cases studied. The results were analyzed according to a validation methodology (descriptive facet of tetraedrum) well known in the literature.
O céu que nos protege: a desertificação das relações humanas
(Universidade Federal de São Carlos, 2014-06-09) Rodrigues, Ana Claudia; Monzani, Josette Maria Alves de Souza; https://lattes.cnpq.br/0505156751073470; https://lattes.cnpq.br/6190989283414190
And the world at full speed, with its re-engineering and mass production, would bring hope to men. It was possible to believe in the prosperity of technique as a compensation for the gap imposed by the Second World War. In a blend of sepia and black and white, reminder of a bygone cinema, the screen is filled as progress, speed and the principle of quantitative values are announced. Industries and factories, cars and trams, dynamism and rush, skyscrapers and neon: here is the synthesis of the universe portraited in the beginning of The sheltering sky (1990), by Bernardo Bertolucci. As colours invade the screen, through a sequence of shots, as they indicate new happenings, the essence of all that excess was made as though it was pulled away with tweezers: Port, Kit and Tunner would lead, starting from that diegetic instant, not only their own peculiarities, but also the universalization they fitted in. Thus, in the face on the mentioned anticipating elements of a leading image for the awake senses of the spectators, we seek to analyze Bertolucci s film in the meanderings of its own historical contextualization in which the characters are inserted, since they would be sharp representation of a recent second post-war, and they saw their own rebuilding in the progress of technique and therefore, through this idealization, they walked forward searching for the compensation of intrinsic gaps. But it is clear that the characters behaviour will not be restricted to the 50s but rather on the contrary, once in earlier circunstances the individuals can be seen in the look for a path, a way out from their loneliness or any other aspect concerning the sense of their existence. In the same way, nowadays , by the means of a visible technology serving a market in constant renovation, anchors reshaped in new disguises are evident, remoulding the idea of new , are evident, and these are constantly committed to the compensation of an existencial void, of a crossing in the quest for a hold for the individual. So, starting from the very genesis of the film precursor tracks common to the creative progress, of which there are no certainties, but intuition, deduction sensitive to the heterogeneous remittance of art, the route narrated in each segment of the film will be establishing itself gradually, always by the light of a methodology fit to outline each character by their own action in order to insert them in the categories given by the diegesis itself, such as travellers, tourist and those who would be in the simultaneity of those determinations, which we can name passengers all of this indicating different manners of seeing the world. Alongside whit those classifications, it is sought to establish the very path of the aesthetic element through the trails of those individuals, first in a fleeting principle, that is, easily falling in forgetfulness, through the linkage of a time in synchrony with the past of tradition, with the present of its fulfillments and with the future pointing at wherever there may be a look of reception. Thus, between the ephemerity of things and the firmness of senses, between men s trends in the front of their supposed arts and of the perennial building of the individual mirroring himself in the immortality of the artistic object, this analysis of the film The sheltering sky begins.
Vegetação de cerrado e conservação : relação entre teorias, influência da escala e variação espacial
(Universidade Federal de São Carlos, 2014-06-09) Baldoni, Raquel Negrão; Matos, Dalva Maria da Silva; https://lattes.cnpq.br/4728734263109138; https://lattes.cnpq.br/6904975996650586
A community can be defined purely as a group of individuals in a certain area? Since the beginning of ecology as a science, many authors have proposed theories to explain the structure of plant communities and therefore the spatial variation. However, although the accumulated knowledge has advanced to challenge the theories with each other, we have not reached many consensus within the community ecology. Likewise it has not been an easy task to establish physical or functional boundaries between the plant communities in the field, has also not been easy to establish boundaries between theories, approaches and influences of diferents areas of science, such as the biogeografia and evolution. Although some researchers have been working on attempts to establish an integrated theory was not only achieved little success and earned the antipathy of many trends or incited passions in scientific circles. On the one hand, the structure of the plant community may be the result of chance that accumulates over time and space, or by environmental heterogeneity due to specific ecological adaptations of different species. On the other hand, the gradient study indicates recognition of closed communities separated by transitional areas whose influence among communities, such highly dynamic areas, regulate their diversity, as endemic center would be essential for management and maintenance actions. Thus, the thresholds may reflect discontinuities on many different levels, but all kinds of limits can help to draw the line where there is success or failure in the prevalence of survival, growth and reproduction, sufficient to prevent the extinction of a species. In this context, the objective of this work is especially to propose a new old way to look at the structure of plant communities, trying to recognize the principles of the proposed theories from the scale of influence on spatial variation in community composition. Still, considering the current context of environmental changes caused by human activities, we will evaluate the effect of artificial transitions in the structure and diversity of communities. Furthermore, given the important contribution of ecotonal areas as endemic centers, we evaluate the contribution of the occurrence of threatened species in these areas for the Brazilian ecosystems conservation status. In this analysis, greater focus was given to the Cerrado, as the Brazilian Phytogeographic Domain presenting transition areas with almost all other ecosystems, with the exception of Pampa. Our results indicated a greater heterogeneity among the grasslands than in the savanna, but in thin scales both guard similarity close to 1, with a higher similarity between samples than expected by chance. This allows us to consider that the fine-scale continuum theory applies to structuring of communities and its spatial variation. In a coarser scale, communities vary as of continuum, in which the case studied in Itirapina Ecological Station, the continuum is represented by the part of Coutinho's gradient ("Grassland – Savanna - Forest") as Grassland-Forest. However, within a mosaic of ecotones and homogeneous types of vegetation, we find gradients nested with the refinement of the scale. In this case, the influence of the scale in approaches to the structuring of the Cerrado communities could be related to fractals, from the recognition of repeated linked units. Considering the intense fragmentation of the Cerrado vegetation, the invasibility of the communities and the biodiversity loss by invasive alien species, it is necessary to carefully evaluate the effect of artificial transitions in the structure of plant communities and establish 3 effective measures of management of invasive grasses for the focus of established invasion. Still, one must consider the ecosystem conservation status are significantly influenced by the heterogeneity that should be considered in priority actions for conservation.
Composição bioquímica de organismos planctônicos visando à aplicação em aquicultura
(Universidade Federal de São Carlos, 2014-06-09) Rocha, Giseli Swerts; Melão, Maria da Graça Gama; https://lattes.cnpq.br/8342306603661310; https://lattes.cnpq.br/9522932409165588
Aquaculture is an activity of great importance in food production, but fish survival in post- larval stages represents a big challenge. Artemia sp. is successfully used as live food, but is expensive and one of the alternatives to reduce costs is to use native species, such as natural zooplankton and fairy shrimp Dendrocephalus brasiliensis, phylogenetically close to A. salina. This study examined how changes in nutritional conditions affect the algae Ankistrodesmus gracilis, and the biochemical composition of D. brasiliensis, Artemia sp. and Daphnia magna. Moreover, we studied how different combinations of food affect the biochemical composition of Atlantic cod (Gadus morhua). The results showed that the availability of phosphorus and copper alter the biochemical composition of algae and affect the production of chlorophyll, growth rates and resistance to metal; D. brasiliensis showed good results in terms of the content of carbohydrates and protein, and a change in the lipid composition according to sex and stage of development of animals; cod showed better results when feed on wild zooplankton added to the cultivated and enriched organisms (rotifers and Artemia) in tanks. Based on these results, we conclude that the environment and nutrient availability in the case of microalgae, affects the biochemical composition and ability to handle contaminants. The biochemical composition of zooplankton can affect higher trophic levels, affecting both the biochemical composition. For these reasons, it is important to know the optimal cultivation conditions in order to achieve the best results in each trophic level.
Avaliação da eficiência e modelagem matemática da remoção de material particulado em canal gramado integrante de técnica compensatória construída em escala real
(Universidade Federal de São Carlos, 2014-06-09) Felipe, Mayara Caroline; Moruzzi, Rodrigo Braga; https://lattes.cnpq.br/9408665052901005; https://lattes.cnpq.br/1287505734500290
A math model was applied to describe the removal of particulate matter in lawn canal built in real scale. For this purpose different initial concentrations (Co) of particulate matter were investigated, as following: 65; 131; 196; 262 and 327 mg/L. The investigated rains, containing suspended solids, were discharged on the channel which has 100 m in length and slope of 2 %. Measurements were made of particulate material through the analysis of turbidity and total suspended solids (TSS) in 26 locations along the length of the channel. The experimental data were fit to the model using nonlinear regression parameter (kd) and (C*), which correspond to the decay kinetics constant and minimum limiting values the curve removal, respectively. Fractions removed and mathematical adjustment were assessed and performed for each isolated event and also for the result set. On average, the magnitude of the relative error ranged from 0.83% to 5.11%, with the highest average value obtained for the lowest concentration of particulate matter (65 mg L- 1). Regarding the values obtained for the decay constants (kd ), which represent the frequency of removal of particulate matter, it is noted that the same trends to a minimum value for the higher initial concentrations of particles (Co) . This fact indicates that the higher the initial concentration of particulate matter (Co), the greater the extent of travel required for its removal, with a maximum observed at around 80 m, for concentrations above 196 mg.L-1.