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Levantamento da curva de custo de usinas eólicas para a definição de preços em contratos do PROINFA gerenciados pela Eletrobras
(Universidade Federal de São Carlos, 2021-06-07) Toledo, Guilherme Ferraz; Lage, Guilherme Guimarães; https://lattes.cnpq.br/4426242038269208; https://lattes.cnpq.br/3374937456491140
A matriz energética elétrica brasileira vem se alterando com a ajuda de programas de incentivo a energias renováveis, buscando menores custos e um ganho maior com bem estar social. Assim faz-se necessário a integração de fontes de energia alternativas às convencionais na resolução de problemas de despacho econômico, que tem por objetivo encontrar o ponto ótimo de alocação de energia em um sistema de potência. Esse problema pode buscar tanto minimizar custos, quanto maximizar lucros ou o ganho social. O presente trabalho busca desenvolver um método para encontrar a função custo de geração eólica para aplicação em um despacho ótimo buscando maximizar a função bem estar social na produção de energia eólica. Esse método procura caracterizar as curvas de velocidade de vento a partir da função de densidade probabilidade de Weibull para que possam ser considerados os aspectos incertos da produção de energia eólica ligados à superestimação e subestimação de potência eólica disponível, assim como estimar o custo de implementação de um complexo eólico e de manutenção do mesmo. Portanto é feito um estudo de caso com um sistema de 6 barras sendo três de geração e três de carga chegando no valor ótimo para o preço da energia que pode ser utilizado para valoração dos contratos do PROINFA para geradores eólicos.
Capacidade resistente de vigas celulares mistas à instabilidade no montante de alma
(Universidade Federal de São Carlos, 2021-06-07) Ferreira, Felipe Piana Vendramell; Martins, Carlos Humberto; https://lattes.cnpq.br/1665294496138141; Nardin, Silvana de; https://lattes.cnpq.br/5587716781980132; https://lattes.cnpq.br/5933034803347448
The present work aims to investigate the web post buckling resistance of composite cellular beams. For this task, geometrical and physical non-linear analyses are developed in the ABAQUS® software. The computational model was calibrated considering physical models of composite cellular beams, with steel-concrete composite slabs, and steel-concrete composite beams with precast hollow-core slabs. Subsequently, the numerical models were unified to represent the composite cellular beams associated with precast hollow-core slabs. Two parametric studies were carried out, varying the cellular beams key parameters, such as the web-post width and the opening diameter. The first study evaluated the floor systems, considering steel-concrete composite and precast hollow core slabs. The second study investigated the composite action, varying the spacing, with one and two connecting lines, between the shear studs. In the first study, considering the section with double symmetry and precast hollow core slab, the predominant failure mode was web post buckling. For the section with asymmetry, the predominant failure mode was the combination of the plastic mechanism with the web post buckling accompanied (or not) by the shear stud rupture. In the analysis of the type of slab it was found that the composite cellular beams with precast hollow-core slabs presented greater resistance. The results of the first parametric study showed that the resistance of the composite cellular beams was not limited only by the resistance of the cellular profile, but also, of the slab, due to the shear resistance. On the other hand, in the second parametric study, a drop in global shear resistance was observed due to the absence of shear studs above the second opening, close to the support. The numerical models of composite cellular beams with hollow-core slab and concrete topping presented greater global shear resistance than the models without concrete topping. However, for those models with concrete topping, there were a greater number of observations in which the shear studs rupture occurred. Finally, the results of the second study were compared with a proposed equation, which takes into account the global shear resistance due to web post buckling, Vierendeel mechanism and composite action. The proposed analytical model showed an excellent correlation with the results of the numerical analyses, especially for the models in which the combination of the web post buckling with the plastic mechanism was identified.
Produção científica sobre saúde indígena na biblioteca virtual em saúde Brasil (BVS): um estudo bibliométrico
(Universidade Federal de São Carlos, 2021-06-07) Almeida, Natalia Rodrigues; Ogata, Márcia Niituma; https://lattes.cnpq.br/3274294833403570; https://lattes.cnpq.br/6131439730455834; https://orcid.org/0000-0001-7011-188X
The history of indigenous population has been marked by tragic epidemics of infectious and parasitic diseases and in 2020, with the pandemic of COVID-19, the political, social and environmental vulnerability of these populations is even more evident. Therefore, it is considered essential to know the scientific production about these populations considered vulnerable due to their space and socio-cultural expropriation and how close it is to the priority needs of health care. This study is justified in the sense of contributing to identify knowledge producers in research on indigenous health, providing evidence of institutional centrality and the possibility of greater investment in research in indigenous health. The Science, Technology, Society field allows us to analyze aspects that provide this construction: who researches, what is researched and for whom it is researched. Thus, the research has as its general objective to map and quantify the scientific activity in Brazilian indigenous health through bibliometric methods considering the year of publication, journal, author and keywords. As for the methodological procedures, it is classified as descriptive with a quantitative approach. The informational source chosen for the research was the Virtual Health Library Brazil, which is an integral part of the Virtual Health Library for Latin America and the Caribbean and to assist in the organization of the data, the StArt tool was used. From the search strings used in the VHL Brazil portal, 1083 articles were identified; after reading the articles and predefined inclusion and exclusion criteria, 126 articles were kept for analysis purposes. For the discussion of articles from the perspective of Science, Technology and Society, it was considered important to indicate: indigenous cultural issues on each theme; change in habits and aspects related to technologies. The year indicator showed considerable growth only in 2014, with more periods of stability than growth or retraction of publications. The periodical indicator presented the Public Health Notebook with the largest number of publications. Regarding the author indicator, the one that most published in the analyzed period was Santos, Ricardo Ventura. And from the indicator of the keywords of the articles, it was possible to find out which themes were most addressed in the period from 2010 to 2018 and they are: oral health, followed by women's health, tuberculosis, nursing and surveillance and nutritional status. As a limitation of the research, in order to better understand the scientific progress in relation to the recovered targeted subjects through the StArt tool research, it should be pointed out the need for an analysis of the articles in relation to the methodological issues; it would also be interesting to expand the study to books, theses and dissertations and scientific events. In addition, it was observed that the theme of women's health has 4 lines of research in the Research Priority Agenda of the Ministry of Health, which would be a specific theme to be studied in new research.
Estudo de caso de estabilização de taludes em área urbana com estruturas mistas de solo grampeado e cortina atirantada
(Universidade Federal de São Carlos, 2021-06-07) Paiva, Carolina Trindade; Bonuccelli, Teresinha de Jesus; https://lattes.cnpq.br/1193172622501312; https://lattes.cnpq.br/3948859432677203
In Brazil, earth retaining structures have been frequently used as a resource to improve urban areas utilization. The increase of urbanization and demographic index demands, as a side effect, the use of underground parking fields, tunnels, and new urban roads. To extend urban space and provide security against soil collapses, studies in geotechnical engineering are crucial and need to be constantly improved. Due to the diversity of geological contexts, careful and detailed analyses must choose the most appropriate earth retaining structure. In this sense, this work has studied and discussed two types of earth retaining systems that are the most applied by civil engineering in urban roads: soil-nailed and anchored walls. We review the literature regarding the two systems and the main calculation methods for slope stability analysis. Particularly, it was studied slope stability cases of two cut walls implemented in an avenue expansion project at Salvador city, state of Bahia. The analysis of the results indicated that the mixed use of soil-nailed and anchored wall for slope stability of a cut wall was the most coherent solution in terms of technical and economic feasibility.
Materiais de eficiência melhorada baseados em zeólita clinoptilolita, macro e micronutrientes e biopolímeros
(Universidade Federal de São Carlos, 2021-06-07) Binotto, Vilma Damian Dias Neves; Pereira, Tamires dos Santos; https://lattes.cnpq.br/8140406570277041; Faez, Roselena; https://lattes.cnpq.br/0654750186618555; https://lattes.cnpq.br/8944425850139846
There has been exponential population growth and, consequently, an intensification in the use of fertilizers. The overuse of fertilizers generates environmental impacts, due to the leaching and volatilization of fertilizers, which can contaminate soil and water. One of the ways to minimize these impacts is to use enhanced efficiency fertilizers which allows the proper use of nutrients according to the demand of the plants, reducing both the environmental and economic impact. Additionally, the use of materials from natural sources and with potential for biodegradation contributes to the sustainability of system. In this work, tablets of enhanced efficiency were developed, composed of clinoptilolite zeolite matrix adsorbed with macro (K) and micronutrients (Cu, Zn, Mn, Fe) and covered by crosslinked alginate and chitosan. Initially, the process of adsorption of nutrients by zeolite was evaluated and applied to mathematical models to determine the kinetics and isotherm of adsorption. From the zeolite / nutrient powder, tablets were obtained by pressing and covered with polymers using dipping technique. Through the kinetics process, it was possible to conclude that K fits the first-order equation, that is, it is adsorbed on the zeolite by physisorption. The micronutrients are adsorbed to the zeolite by chemisorption. Through the difference between the adsorption capacity of the nutrients and the concentration, it was determined that the Langmuir’s isotherm was most suitable for the nutrient ions evaluated implying that the nutrients are linked by monolayer. The Freundlich isotherm, in which nutrients tend to organize themselves in multilayers under the zeolite, was the one most suitable for Fe. Preliminary data on the release of tablets in water show that the coating prolongs the release of nutrients. Within this context, it was found that this theme is very promising to be worked on in the classroom, as there are a variety of themes (contamination of effluents, water, fertilizers, food, plant growth, etc.) that can be worked in an interdisciplinary way, with this, two learning proposals were developed addressing these topics. We can conclude that the work has the potential to contribute to a better use of nutrients by plants and the reduction of environmental impacts, in addition to promoting an important approach on sustainability for teaching