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A modelagem de gráficos de controle de aceitação condicionados aos índices de capabilidade de processos : uma abordagem prática e econômica
(Universidade Federal de São Carlos, 2017-07-07) Costa, Fabrício Martins da; Oprime, Pedro Carlos; https://lattes.cnpq.br/9291517431456908; https://lattes.cnpq.br/8889391896878916
Modified and acceptance control charts allow a new approach to statistical process monitoring. This research topic is little explored in the academic world, thus, this thesis contributes to the advancement of statistical process monitoring methods, both in theory and practice. Some decisions about the quality of processes and products are based on a set of economic and practical factors that involve their context, not just a probability, p-value. Statistical significance considers the theoretical decision probability of the statistical hypothesis test, and does not take into account trade-offs when choosing a decision alternative. In this work, when studying the X-bar R/S graphs, the hypothesis is that the limits of statistical control can be determined considering practical aspects. The model proposed in this thesis will be based on the acceptance graphs and on the capacitance indices, Cp and Cpk. The use of these indices is justified because they are widely used by the manufacturing industry, and these represent the practical aspect in the decisions about processes and products. The performance of control charts was evaluated via ARL (Average Run Length). An ARL model was developed when parameters are unknown, including the capability indexes. The results indicated that the proposed graph performs better than Shewhart's traditional charts. An implementation method was proposed and an illustrative case was carried out. In the illustrative example, the proposed method provided a smaller type I error, making it possible to improve the quality level in the process result.
Estudos de resíduos agroindustriais brasileiros como fonte de compostos de alto valor agregado: métodos verdes para a extração de flavonoides derivados de resíduos de laranja
(Universidade Federal de São Carlos, 2017-07-07) Ramin, Luize Zola; Zuin, Vânia Gomes; https://lattes.cnpq.br/5265150425993880; https://lattes.cnpq.br/0709683380713155
Currently, there is a need to increase the research aimed at the recovery of agro-industrial and forest residues worldwide. The food industry has produced an enormous amount of waste globally, among them the citrus waste that has a high potential to added value compounds, such as soluble sugars, cellulose and hemicellulose, pectin, d-limonene, ethanol and flavonoids. In this context, the aim of this project is to develop green methodologies applied to the extraction and analysis of natural bioactive compounds, such as flavonoids from orange waste derived of conventional and organic farming process. The sample preparation was carried out based on green techniques (microwave assisted extraction, ultrasound, conventional extraction with homogenizer aid), and a quantitative and qualitative determination through chromatography‘s techniques coupled to UV-Vis detector. In order to understand the behavior of the bioactive compounds of this matrix, four flavonoids (hesperidin, naringenin, hesperetin and nobiletin) were studied. The results showed that these compounds have a similar behavior to the variables tested, such as solvent extractor, temperature, time, among others, however they present differences when those are applied together in the different methods.
Modelagem ambiental de áreas degradadas por processos erosivos, com vista ao planejamento ambiental–São Pedro e Santa Maria da Serra/SP
(Universidade Federal de São Carlos, 2017-07-07) Piga, Fabíola Geovanna; Ferreira, Marcilene Dantas; https://lattes.cnpq.br/1557946634389893; https://lattes.cnpq.br/3388784466110676
Global and local environmental changes are almost always associated with the increase of human activities, whose impacts cause significant transformations of the environment. These changes are linked to several socioeconomic and socioenvironmental factors, such as population density, urban expansion, agricultural expansion, deforestation, industrialization and the increasing production of solid waste, compromising the availability of natural resources and the quality of the environment. In view of these considerations, this work had the objective of elaborating an environmental diagnosis, in the face of erosive processes, through the use of the Geographic Information System (GIS) associated with soil loss prediction models, analyzing the dynamics of land use and land cover Over the years, and integrating the various physical and environmental factors to determine the degree of susceptibility of the environment through environmental fragility. For this purpose, an area characterized by intense erosion processes was selected, comprising the municipalities of São Pedro and Santa Maria da Serra, which has a direct contribution to the sediment load in the Barra Bonita Reservoir. In addition, such an area is part of the Corumbataí APA, that by law the preservation and conservation of its landscape should be ensured. The results showed that the area has suffered from the problem of erosion for more than 60 years and little has been done to reverse this situation. The year of 2015 was the one that presented the greatest loss of soil, and the expansion of the urban spot and agricultural areas caused a high fragility of the study area. This scenario demonstrates that the role of APA is not being addressed since its purpose is to balance local socioeconomic development with the sustainability of environmental resources. This study allowed the delimitation of areas restricted to anthropic interventions, which require greater care, and areas with greater aptitude for urbanization, contributing to the study of urban and environmental planning.