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Análise da aplicação de modelos de otimização linear na solução de problemas de dimensionamento de lotes e sequenciamento da produção de bebidas.
(Universidade Federal de São Carlos, 2017-11-24) Noble Ramos, Victor Mario; Ferreira, Deisemara; https://lattes.cnpq.br/0245267028273903; https://lattes.cnpq.br/9414682020715601
This dissertation adresses the general integrated lot sizing and scheduling problem for non-alcoholic beverage production with synchronization between stages and operating time windows for scheduling preventive maintenances. The problem is characterized by having two interdependent synchronized stages. In the first stage, machines (tanks) can supply several filling lines at the same time in the second stage, where the final items are packed. Production sequence-dependent times and costs exist. The review of the related literature indicates that existing models refer, generally, to particular cases of the general problem adressed here, the most common cases are the dedication of tanks to the lines, and disregarding the perishability of syrups and the possibility of scheduling preventive maintenances. A mathematical model for the general problem, called SMMRPM, has been proposed and applied in several instances to show the adherence and flexibility of the model to represent practical cases that can be found in reality. For the case of the dedication of tanks to lines, the model was compared with the dedicated model F1 (FERREIRA et al, 2012). The results indicate that the SMMRPM model is flexible and adherent to represent practical scenarios in which other models are not applicable, for example the possibility of scheduling preventive maintenance and consideration of perishability are differential of the proposal. In the plans obtained, it was shown that it is important to include these considerations that significantly affect the productive plans. In the case of dedication, compared to the dedicated model, the formulation SMMRPM achieves production plans, on average, 52.63 \% less costly than F1.
Efeitos isolados e combinados dos inseticidas fipronil e tiametoxam para a abelha brasileira Melipona scutellaris Latreille, 1811 (Hymenoptera, Apidae)
(Universidade Federal de São Carlos, 2017-11-24) Araújo, Jéssica Freitas; Nocelli, Roberta Cornélio Ferreira; https://lattes.cnpq.br/8934724759636382; https://lattes.cnpq.br/5882656009354609
Pollinators are responsible for tropical forests polinization and also have direct and indirect action on human feeding. The pollinators are majorly represented by bees. Even though, this contribution has been affected by numerous factors, among them, agrochemicals. The tiametoxam and fipronil insecticides, from neonicotinoides and fenilpirazois classes, respectively, present numerous negative effects, including biochemical alterations, in different bees species. Therefore, the aim of this paper was to analyze, through biochemical techniques, acetilcolinesterase (AChE) and carboxilesterase (CaE) enzyme activities in the head and glutationa S-transferase in the intestines of Melipona scutellaris worker bees, exposed to the mentioned insecticides, combined and isolated. Bees forage were collected and divided into four experimental groups: Control, acetone control, LC50/2 (0,0226 ng i.a. tiametoxam/μL and 0,0056 ng i.a. fipronil/μL) and LC50/5 (0,00906 ng i.a. tiametoxam/μL e 0,0022 ng i.a. fipronil/μL) orally exposed, combined and isolated, for 1, 6, 12, 24, 48 and 96 hours. The brain and the intestines were dissected, weighted and submitted to LS drainage buffer solution, macerated and centrifuged. The absorbance readings were done in 412, 410, and 340 nm wavelength, respectively. The data was analyzed by the Mann – Whitney e Kruskal – Wallis tests. The results showed alterations in the AChE tissue activity to the fipronil insecticide raising in 1 hour (LC50/2 and LC50/5) and decreasing in 6 hours (LC50/2 and LC50/5) and 12 hours (LC50/2) and raising again in 96 hours (LC50/2 and LC50/5). To the tiametoxam insecticide there was a decrease at 6 hours (LC50/2 and LC50/5), 12 hours (LC50/2) and 24 hours (LC50/5) and a raise at 96 hours (LC50/2 and LC50/5). Combining these insecticides it was observed a decrease in AChE LC50/2 activity (6 and 12 hours) and LC50/5 (6 and 24 hours) and a raise in LC50/2 and LC50/5 (96 hours). In specific activity there was a decrease at 6 hours (Fipronil LC50/2 and LC50/5 and Combined LC50/2), 48 hours (Tiametoxam LC50/5) and 96 hours (Fipronil LC50/2 and Combined LC50/5). The following patterns were detected for the detoxification enzyme tissue CaE-3: Fipronil insecticide – decrease in 12 hours (LC50/2) and raise in 96 hours (LC50/2) and combined – activity decrease in CL50/5 group (6 hours). Differences statistically relevant weren’t identified in groups exposed exclusively to tiametoxam insecticide. Considering the GST activity, the acetone group obtained raise in one hour exposure; groups exposed to the fipronil insecticide LC50/5 (1 hour), LC50/2 and LC50/5 (96 hours) obtained decrease and raise in this enzyme activity, respectively. Considering tiametoxam insecticide it was observed a raise in the activity at 6 hours (LC50/2 and LC50/5) and at 12 hours (LC50/5); there was increase in the combination for the groups: LC50/2 (48 and 96 hours) and LC50/5 (6 and 12 hours). This way, we can conclude that the insecticides, combined or isolated, affect the analyzed enzymes, reflecting in the toxicity of these individuals when exposed to sublethal doses; they may cause death of the individuals, hives destructure, and impact ecosystem directly.
Solidificação, microestrutura e propriedades mecânicas da liga de alumínio 6061 com 1,4%p Fe processada por conformação por spray e extrusão a quente
(Universidade Federal de São Carlos, 2017-11-24) Pereira, Leandro Henrique; Bolfarini, Claudemiro; https://lattes.cnpq.br/9231627080617037; Botta Filho, Walter José; https://lattes.cnpq.br/8956458007749112; https://lattes.cnpq.br/1420586030063798
The 6xxx series aluminum alloys are wrought alloys which belongs to the MgSi class and can be heat treated, have a good workability and a good mechanical resistance / weight ratio. A great challenge is to avoid impurity elements in the aluminum alloys, like iron during the recycling cycle. The main effects of this type of elements are the formation of a coarsed microstructure and the nucleation of undesired intermetallic phases with a morphology that acts as stress concentrations and decreases the mechanical properties. The aluminum alloys that contains Fe are considered complex due to a range of intermetallic compound that can be formed. Due to the chemical composition of this alloy, this work will give some attention to intermetallic phases formed with low Fe content, like α-Al8Fe2Si phase and β-Al9Fe2Si2 phase. This study analyzed the solidification, microstructure and mechanical properties of an AA6061 aluminum alloy with 1.4%wt. of iron content produced by spray forming and hot extrusion, with the purpose of developing an recycling route that allows mechanical processing of the aluminum alloys with high Fe contamination. During the analysis of solidification and microstructure, it was noticed that the spray forming process change the alloy’s solidification path, also altering the morphology of the present phases. The mechanical characterization allowed the understanding of the effects caused by the contamination of iron on the mechanical properties of the alloy studied.
Uma sequência didática para o ensino de poliedros explorando o movimento lógico-histórico do conceito
(Universidade Federal de São Carlos, 2017-11-24) Lima, Wilson Francisco da Rocha; Sampaio, João Carlos Vieira; https://lattes.cnpq.br/8286887389013685; https://lattes.cnpq.br/3420534562917526
The purpose of this work is comprehend and bring to the classroom environment a trajectory of the polyhedron as a concept through the history of human knowledge seeking to answer the following question: How would a didactic sequence that addressed the contents related to polyhedra that make up the curriculum of current Mathematics classes in a critical way, contextualizing the knowledge with the historical moment in which it was developed and articulating the contents with current researches of Scientific Mathematics? With Vygotsky's socio interactionist theory and Marx's dialectical materialism as a background, this work explores the presence of History of Mathematics on education in a sociocultural perspective, considering teaching-learning situations that can provide means of dialogue between the school culture and the one which the concept being taught initially appeared. Using as methodology the Didactic Engineering, a didactic sequence divided into three teachinglearning situations about polyhedrons was elaborated according to the curriculum and applied to middle school students. Based on the works of Greek philosophers Plato and Euclid and the Swiss mathematician Leonhard Euler, the sequence explores from main aspects of geometrical figures to the origins of Topology as an introduction to the conception of tridimensional objects on that field of Mathematics
Filmes finos de Zn(1-x)Cu(x)O crescidos por Spray Pirólise
(Universidade Federal de São Carlos, 2017-11-24) Silva, Diego Scolfaro da; Godoy, Marcio Peron Franco de; https://lattes.cnpq.br/2609654784637427; https://lattes.cnpq.br/3636859018525865
This work consists of investigations of the structural, morphological and optical properties of thin films of the Zn(1-x)Cu(x)O system grown on glass substrate using the Spray-Pyrolysis technique with Zinc and Copper acetates as precursors and work temperature in the range of 220°C and 300°C. Our research was based on the growth of the samples varying the Copper concentration from 0 to 100%, followed by the measurements of X-ray Diffraction (XRD), Scanning Electron Microscopy (SEM), Optical Absorbance and Transmittance and Photoluminescence (PL). Finally we tested an application of the samples by studying the effects of different atmospheres on the Photoconductivity (PC). The structural characterization shows the growth of polycrystalline films with Wurtzite structure at Copper concentrations up to 10% and monoclinic structure at concentrations starting at 90%. Intermediate concentrations result in films exhibiting the two crystalline phases in coexistence. The crystalline quality accompanies this phase progression and the mean crystallite size is in the range of 9 to 14 nm. SEM images shows homogeneous surface with increasing roughness proportional to the amount of Copper. The Absorption Edge is reduced by the incorporation of Copper atoms in the structure, ranging from 3.31 eV for ZnO to 2.02eV for CuO. It is possible to detect the direct transition for all samples and an indirect for samples with copper concentration from 25%. In addition we show an increase in the absorption coefficient in the visible region. The photoluminescence of ZnO shows that the excitonic and defect-related transitions are present. The photoconductivity of ZnO is strongly dependent on point defects and the concentration of Oxygen in the atmosphere, whereas for CuO, photoconductivity shows little dependence on the atmosphere.
A série Free!: conexões entre “genre” e “gender”
(Universidade Federal de São Carlos, 2017-11-24) Silva, Michele Delbon; Paiva, Samuel José Holanda de; https://lattes.cnpq.br/7222933274927263; https://lattes.cnpq.br/8016259400285266
The present research proposes a reflection on "gender", as the formulation of audiovisual discourses, and "genre", in the sense of the social construction of sexualities. To do so, an analysis was conducted about the first season of Free! (2013), relating it to yaoi, a genre of Japanese animation focusing on homosexual relationships between male characters. Taking the theories of Judith Butler as the starting point, a North American post-structuralist philosopher, and Antonia Levi, Japanese historian, this research seeks to formulate a method of reading to be coupled with film analysis within the perspective of the questioning about audio-visual and sexual discourses.