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Percepção dos predadores de ninhos e estratégias anti-predação numa comunidade de aves da Mata Atlântica do estado de São Paulo
(Universidade Federal de São Carlos, 2019-04-25) Zima, Paulo Victor Queijo; Francisco, Mercival Roberto; https://lattes.cnpq.br/4305313620456233; https://lattes.cnpq.br/5470526061536444
The main cause of annual variations in bird’s reproductive output is the failure of nests resulted from predation. Eggs exposed in open nests, usually have a wide range of colorations, and may coincide with the color of the nest material, which can be considered as a mimetic strategy to avoid predation. Many hypotheses have predicted that nest characteristics and the characteristics of its surroundings also affect nest predation probability, but many of these hypotheses are still poorly tested. One such hypothesis is the ''potential prey-site hypothesis''. In this work we tested the effects of egg color in nest predation, using plasticine eggs with three color patterns, in natural nests of the Blue Manakin, Chiroxiphia caudata, and we extended the theory of the''potential prey-site hypothesis'' by addressing nest-like structures in a Atlantic Forest well-preserved area. For the first experiment we used 78 abandoned nests of the Blue Manakin, 26 with each egg pattern (all white, white with brown spots, and all brown), of which 11 (14.10%) nests were depredated by visually oriented predators: (five with white eggs; four with white eggs with brown spots; and twowith brown eggs). Although there were no significant differences in the probability of predation for each color pattern, there was a growing tendency, in which white eggs had the lowest survival rate, followed by white with brown spots, and finally the all-brown eggs. To address the ''potential prey-site hypothesis'' we first tested if the Blue Manakin could select nesting sites in which nest-like structures, such as tufts of moss and deposits of debris in horizontal forks, were in higher densities, controlled to a set of covariates. Then, we evaluated if the numbers of nest-like structures in nest surroundings were correlated to nest survival, using 42 active nests. Modelings using Generalized Linear Models indicated that nest-like structures and vegetation density were the main covariates explaining nest site choice in this species. However, we found no correlations of nest-like structures to nest survival, which corroborates only partially the ''potential prey-site hypothesis''.
Pré-seleção de fornecedores no contexto de negócios e Indústria 4.0 utilizando MCDA
(Universidade Federal de São Carlos, 2019-04-25) Spinardi, Maurício; Faceli, Katti; https://lattes.cnpq.br/4451540730749377; https://lattes.cnpq.br/6478343724225588
With the current trend of modernisation, automation and data exchange, also known as Industry 4.0, the number of new actors in the corporate environment has grown, along with the need for tools to streamline industrial processes. Computing platforms, such as e-marketplaces, seek to respond to this demand by providing resources to facilitate the initial connection and relationship between clients and suppliers. However, business-tobusiness e-marketplaces still have a number of limitations, such as the high specificity inherent in the supplier selection problem. Considering this problem and context, this study proposes a new approach to supplier selection in e-marketplaces. In this approach, the problem is divided into two stages: pre-selection, carried out by the e-marketplace, and final decision, carried out by the client. Functioning as a filtering process, the aim of pre-selection is to construct a short, pre-processed list of alternatives for the second step – the final decision – to simplify and streamline the client’s analysis. To verify the utility and feasibility of pre-selection, a methodology structured around four main steps was proposed: (1) defining a multi-criteria decision analysis technique, (2) defining pre-selection criteria, (3) validating and defining the respective weights for the pre-selection criteria and (4) defining a proposal for rejecting suppliers. Consequently, this approach streamlines the efficiency of the selection process and improves the maintainability of e-marketplaces.
Seleção de fornecedores sob incertezas via otimização robusta
(Universidade Federal de São Carlos, 2019-04-25) Tavares, Cassiano da Silva; Godinho Filho, Moacir; https://lattes.cnpq.br/6136685270563354; Munari Junior, Pedro Augusto; https://lattes.cnpq.br/1328868140869976; https://lattes.cnpq.br/0316636213886070
This paper studies the problem of selection of suppliers under uncertainties, motivated by the current economic situation of world trade. The fierce search among the organizations for responsiveness in meeting the market demand has been directing efforts for optimization in the supply chain. One of the main links in this context is the supply of raw materials. The rupture of the supply of a raw material can cause the blockade or paralysis of the entire organizational system, leading to an operational failure to meet a demand, damaging the image of the organization to the market. The decision of the best choice of supply has become a vital activity for organizations in the current scenario, as the chain's operational performance is strongly tied to this fundamental link. With this, the decision to select suppliers becomes a very complex activity, requiring a high level of precision and assertiveness. The objective of this work is to develop and apply optimization approaches that incorporate the uncertainties in the context in which the global supply of raw materials is inserted through the Robust Optimization approach. Two models of mixed integer linear programming are proposed for the deterministic problem, from which the robust counterparts that model the problem under uncertainties are obtained. The models were implemented using general purpose optimization software. Monte Carlo simulations were performed to determine the performances of the deterministic and robust models in samples of different scenarios, as well as the level of robustness of the solutions. The computational experiments pointed out that the Robust Optimization approach enhances the robustness of solutions in risk aversion when uncertain parameters are involved. This was evidenced by the level of encumbrance promoted in the values of the solutions when a protection to the uncertainty was employed, since the increase in the optimal value of the objective function in the worst case is always smaller than the deviation of the uncertain parameters.
Determinação do equivalente mecânico do calor através de medidas elétricas
(Universidade Federal de São Carlos, 2019-04-25) Dias Junior, Marco Antonio; Souza, James Alves; https://lattes.cnpq.br/2212240621620011; https://lattes.cnpq.br/5367947636556389
Scientific experimentation is a practical activity that can be widely used in the classroom to boost the motivation of students for learning Physics concepts. It can also be promising to improve the relationship between teacher and students. Experimentation can be used as a complementary methodology for the theoretical classes of Physics in order to facilitate the understanding of physical concepts usually treated in an abstract and mathematical way. Experimentation can be applied as a demonstration activity, in which the teacher is the mediator of the activity, or an activity performed by the students themselves, aiming the description of a investigated phenomenon. In this work we perform an experiment for the determination of the mechanical equivalent of the calorie through a different approach to the celebrated experiment carried out by James Prescott Joule. Our goal was to introduce new technologies and devices used to monitor the physical properties of the system for obtaining the equivalent between joules and calories through measurements of parameters such as electric voltage and current. Using a solar photovoltaic cell, as a power source, connected to a resistor inserted in an adiabatic calorimeter, we explore concepts such as heat and temperature and the difference between both, energy, analysis and processes of thermodynamic systems, the laws of thermodynamics and the Joule and photovoltaic effects. Our proposal was successfully received by the students, having a motivating and integrative character. It is also promising for the mathematical treatment of the phenomena described through propagation of errors, by plotting and fitting the curve obtained experimentally and the modeling of the system. Our educational product consists of a guide for assembling the experiment and several suggestions of physical concepts that can be approached during the execution of the experiment in a simple and adequate language for high school Physics teachers.
Políticas agrárias e articulação de escalas: uma análise do ambiente institucional nas compras públicas do município de São Carlos / SP
(Universidade Federal de São Carlos, 2019-04-25) Khalil, Bárbara El; Carvalho, Joelson Gonçalves de; https://lattes.cnpq.br/0141039743607067; https://lattes.cnpq.br/4923394220818843
The reflections about models of rural development have been present in Brazilian’s reality since the 20th century. But to perform an in-depht reflection of the policies which are aimed to it, continues to be a difficult task. We intend to add efforts in this movement, starting from the process of government purchases avaliation in a small city of São Paulo/SP. The study we developed in this dissertation – “Agrarian policies and scales articulation: an analysis of institutional environmet of government purchases in São Carlos/SP” – has a double objective: to understand how agrarian policies relates to local power, from the experience of government purchases and then, identify how the dialogue between local power, campers and agrarian reform settlers happens in São Carlos. Our main hypothesis sustains that the agrarian question materializes itself in the municipality not only by direct conflict, from the struggle for land, but indirectly, by the action of local power, who turns the access to the agrarian policies more difficult for rural populations. As a secondary hypothesis, we understand that the city government stops to being an agent who promotes rural development and becomes an agent who hampers it. After we made our bibliographic reviews, documentary researches, participant observation, sensitive listening and semi-structured interviews with representative agents, we tested our hypotheses and concluded that local power tends to make difficult for rural landless workers and agrarian reform settlers to access the agrarian policies. The conflict makes itself present in the dialogue between Agriculture and Supply Department, campers and agrarian reform settlers.
Seleção de habitat para nidificação por aves em uma área preservada da Mata Atlântica do sudeste do Brasil
(Universidade Federal de São Carlos, 2019-04-25) Perrella, Daniel Fernandes; Francisco, Mercival Roberto; https://lattes.cnpq.br/4305313620456233; https://lattes.cnpq.br/8000839194914765
Birds naturally present a number of ecological requirements to survive in complex habitat environments where they live and the ability to select suitable and safe nesting sites has been shown to be a particularly important adaptive factor in the life cycle of these animals. In Neotropical forests, naturalists have long suggested that even non-aquatic birds often do reproduce near water bodies, which however, is still poorly addressed. From 2016 to 2018, nests of understory birds were studied at Carlos Botelho State Park, São Miguel Arcanjo, SP, and the influences of forest streams for nest site selection and nest survival were investigated, which is presented here in three chapters. In the first chapter, nests were searched near forest-streams and far from any watercourse in an attempt to compare nest density between these two situations. In the second and third chapters, nests of Chiroxiphia caudata, Rhopias gularis and Onychorhynchus swainsoni, which nested near or above forest streams, were monitored and we tested if these species could select specific stretches of the streams to build their nests, and we tested if stream characteristics, i.e. stream width, water depth, and water speed could interfere with their reproductive success. Further, in the third chapter, other reproductive parameters of O. swainsoni, which is endangered, were observed, such as nest and eggs measurements, incubation and nestling periods, breeding phenology, nesting success, and density of reproductive pairs along streams. We found 63 nests of 18 species along streams and only one far from them. We revealed that nest density was much higher near forest streams (5.3 nests/ha), than far from water (0.1 nests/ha). We showed that none of the stream covariates explained nest site selection for the three studied species, although water depth and distance to water were correlated to nest survival for R. gularis. In the third chapter we showed that O. swainsoni selected only the largest forest streams to establish their reproductive territories, and that their reproductive rates and breeding territory densities were low compared to other forest understory passerines, which is likely involved in its rarity. This study comprises the first carried out in the Neotropical region to provide information on nest density in a well-preserved Atlantic Forest remnant, and the streams that permeate this forest seem to provide important reproductive habitats for several bird species, although the mechanisms involved in nest site selection varied among the different species.
Mamãe é a melhor professora!: uma etnografia junto a três famílias que educam suas crianças fora da escola
(Universidade Federal de São Carlos, 2019-04-25) Loreti, Gabriela Braga; Cohn, Clarice; https://lattes.cnpq.br/1714080901123094; https://lattes.cnpq.br/1874338450302264
This ethnography was developed among three families that educated their children out of school. The term education out of the school is used here in its broader form to refer to those situations when grown-ups, either parents or legal responsibles, choose to take direct responsability over their children’s education, avoiding sending them to the educational system, either public or private. Among those practices, there are those known in Brazil as educação domiciliar or não escolarização or homeschooling and unschooling. At the time in which this research was being developed, its controversial legal status was at evidence, being them not regulated, and, at the same time, there was a increase on the number of practitioners or interested families. Thereby, the choice of having the children not attending the school and being therefore educated at home is the conducting wire of this work, that turns to the experiences among the three families, who are seen by their similarities or dissimilarities, to reflect about ideas of family, education, care and children involved in each case. We intend to make this experiences explicit from the displacements proposed by these women, mothers and educators, from the formal education, who explained to me what, for them, is to educated their children out of school as well as, at the same time, how they organized and conducted meals, play times, researches and activities, accompanying those families at home as well as their everyday itinerary when leaving their homes.