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Sistema de produção orgânico de milho (Zea mays L.), feijão (Phaseolus vulgaris L.) e mandioca (Manihot esculenta Crantz) consorciados com soqueira de cana-de-açúcar (Sacharum spp.)
(Universidade Federal de São Carlos, 2009-06-22) Apolari, João Paulo; Margarido, Luiz Antonio Correia; https://lattes.cnpq.br/5685663057214334; https://lattes.cnpq.br/4466408577931725
Greater stability of an agroecosystem can be achieved through the consortium system under organic management, becomes an important environmental factor to a highest stability of the agroecosystem. The objective was to study a system of production for organic crops of maize (Zea mays L., cv. BR 106), bean (Phaseolus vulgaris L., cultivar IAC Pérola) and manioc (Manihot esculenta CRANTZ, cv. IAC 15), intercropped with ratoon-cane (Saccharum spp.). The experimental design was a randomized, with eight (8) treatments and four (4) replicates, as follows: T1 ratoon-cane without intercropping (control), T2: ratooncane and intercropping of maize (cs + mi), T3: ratoon-cane and intercropping of bean (cs + fe); T4: ratoon-cane and intercropping of manioc (cs + ma), T5: ratooncane and intercrops of maize and bean (cs + mi + fe) T6: ratoon-cane and intercrops of maize and manioc (cs + mi + ma); T7 ratoon-cane and intercrops of bean and manioc (cs + f + ma), T8: ratoon-cane and intercrops of maize, bean and manioc (cs + mi + fe + ma). Productivity of the crops, the gross income obtained and the residual biomass waste of maize, beans and manioc, in each system were evaluated. For the conditions of the experiment, the treatment intercropping maize (T2) showed the best results on productivity of green maize ears (kg/ha), production of biomass (kg/ha) and gross income (R$/ha). The alternative of the consortium of distinct crops with ratoon-cane proves to be an effective technique that, from the viewpoint of agroecology, becomes an important tool for preserving and maintaining the agroecosystem, besides providing alternative foods and additional income to the farmer.
Otimização no planejamento agregado de produção em indústrias de processamento de suco concentrado congelado de laranja
(Universidade Federal de São Carlos, 2009-06-22) Munhoz, José Renato; Morabito Neto, Reinaldo; https://lattes.cnpq.br/8506951656740145
This work aim at developing models using linear programming, goal programming and robust optimization to support decision making in the frozen concentrated orange juice planning process. The proposed model includes orange harvesting plan, which takes into account oranges maturation curves. This fact leads to a model that incorporates a large portion of the supply chain involved in the frozen concentrated orange juice sector. Another point to highlight is the inclusion of the blending process of different types of juices to match ratio specification of the product. This study uses orange acidity to calculate ratio specification of the product. This study also explores the importance of data uncertainty incorporation to the aggregate production planning for this business and evaluate results from different approaches of robust optimization to this problem. This author is not aware of previous work in the literature with such approach to the orange juice industry. The problem modeling uses blending problem concepts and production planning with multiple products, stages and periods concepts as well. To solve the linear programming, goal programming and robust optimization models, an algebraic modeling language and a state of art optimization solver of mathematical programming problems is used. A case study was developed in an orange juice company located in the São Paulo State. This company has many facilities and a worldwide distribution system, similar to other companies in this sector. The results show that the proposed approach can be used in real situations.
Estudo da sinterização de compósitos densos de Al₂O₃ contendo inclusões nanométricas de ZrO₂
(Universidade Federal de São Carlos, 2009-06-22) Déo, Luciene Cristina Chiari; Tomasi, Roberto; https://lattes.cnpq.br/8591752492566665; https://lattes.cnpq.br/7728256316655962
The search for materials that posses exceptional hardness, resistance to high temperatures and chemical stability had expanded the areas of application and use of ceramic materials. The development of research about composites containing nanometric inclusions in its matrix increased due to the results of significant improvement in the mechanical properties of composites formed by an alumina matrix with nanometric inclusions of SiC. The mechanisms that enable the improvement of this property have not been fully justified. It was found that the presence of nanometric inclusions delay the beginning of the densification and shrinkage of the samples by raising the temperatura of sintering. This fact was the main motivation for the accomplishment of this work, that had as objective to study the sintering kinetics in the initial stage of alumina samples with and without the presence of nanometric inclusions of zirconia. The study method used was that proposed by Woolfrey and Bannister based on the work of Young and Cutler. With the application of this model, possible mechanisms acting in the system were identified. The samples had been gotten by the desaglomeration of the powders and posterior mixture in mill, isostatic pressing and sintering in dilatometer under constant taxes of heating of 3, 5, 9 and 15 C/min in air, with maximum sintering temperatures of 900, 1000, 1100, 1200, 1300, 1400 and 1500 C. The samples had been characterized how much its apparent density, specific superficial area and microstructure. A change in the mechanism acting in the initial stage of sintering was identified for samples containing nanometric inclusions of zirconia.