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Reconhecimento facial: um estudo comparativo sobre métodos cruzados de PCA e LDA
(Universidade Federal de São Carlos, 2021-11-25) Moreira, Gabriel Renato; Barcellos, Robson; https://lattes.cnpq.br/9844506370403162; https://lattes.cnpq.br/2670843911052624
This work presents a comparative study for tools commonly utilized in facial recognition (PCA and LDA). These tools can be used separately or in association to improve the precison in the recognition.They use libraries like Scikit-learn (Sklearn), OpenCV and NumPy. For each tool, the respective method must be applied to achieve the ideal results.
Reciclagem de PETG para produção de filamentos e aplicação em Manufatura Aditiva
(Universidade Federal de São Carlos, 2021-11-25) Flores, João Daniel Seno; Costa, Lidiane Cristina; https://lattes.cnpq.br/8246109223926480; https://orcid.org/0000-0002-0280-6994; https://lattes.cnpq.br/6090686207316165; Marini, Juliano; Souza, Adriana Martinelli Catelli de; https://lattes.cnpq.br/4533610255047654; https://lattes.cnpq.br/4514700154455911; https://orcid.org/0000-0003-2351-3477; https://orcid.org/0000-0003-1594-8673
In the search for a more sustainable society, one of the main challenges of today is the environmental, social and economic damage caused by the predominance of the linear economy. An alternative is the return of polymeric waste to the production chain (reverse logistics) for application in new manufacturing methods, such as Additive Manufacturing (MA), with an emphasis on Fused Filament Fabrication (FFF). In this aspect, this master's work proposed the application of Poly(ethylene terephthalate) glycol (PETG) residues, arising from the manufacture of Faceshields (Auxiliary EPI to prevent the transmission of Covid-19), for the production of filaments for the FFF. Initially, PETG in flake format was characterized by FTIR, NMR, parallel plate and capillary rheometry, TGA and DSC, identifying in the last it as a semi-crystalline PETG. Subsequently, by simulating 5 cycles of mechanical PETG recycling and obtaining filaments at the end of each cycle, the influence of reprocessing on the rheological and thermal properties of these filaments was evaluated with parallel plate and capillary rheometry tests, TGA and DSC. To analyze the influence of recycling, the 5 filaments were used in the additive fabrication of specimens (Norm ABNT D638 - Type I) with a deposition angle of ± 45° and fabrication quality using a calibration standard (#3DBenchy). Despite the reprocessing causing polymer degradation, verified by the reduction of viscosity and favoring crystallization, all filaments were adequate for application in FFF. In tensile strength there is a growth from the 1st to the 3rd processing cycle and subsequent reduction to the 5th cycle, mainly due to the variation in molar mass and molecular diffusion. In the analysis of manufacturing quality, it was found that the most reprocessed filaments had better surface / dimensional quality due to higher crystallization kinetics.
O problema Fermi-Pasta-Ulam-Tsingou: equipartição de energia vista através de simulações computacionais
(Universidade Federal de São Carlos, 2021-11-25) Lucero, Davi de Mello; Moreira, Pedro Augusto Franco Pinheiro; https://lattes.cnpq.br/5964404207962453; https://lattes.cnpq.br/5059102887005756
The equipartition of energy is one of the most fundamental results of Statiscal Mechanics, appearing in a broad range of physical systems. In order to explore this concept, two computational experiments of the Fermi-Pasta-Ulam-Tsigou paradox were implemented. In one of the experiments the equipartion of enerergy happens and the other one not. The latter experiment leads to the known Fermi-Pasta-Ulam-Tsingou Paradox, with great implications to development of Computational Physics, Statistics Mechanics amongst other fields. The experiments are carried out through a home-made numerical implementation and a computational research tool available on internet and usually adopted by the scientific community. There is a mathematical analysis, using normal modes, to support the computational experiments.
Uma introdução aos inteiros gaussianos
(Universidade Federal de São Carlos, 2021-11-25) Ferreira, Raphael Elias Toledo; Seixas, Wladimir; https://lattes.cnpq.br/1697352974728327; https://lattes.cnpq.br/4643722303426482
This monograph presents the principles of number theory, formally establishing important arithmetic facts that characterize the systems in question. It sought to develop theory in an axiomatic way, from the principles of sets, which constitute the main tool for mathematical rigor. Furthermore, this text presents different domains of integrity, which have many similarities, although for each of these there are specific considerations and precautions to be taken. From this development of systems analogous to the set of whole numbers, it is possible to contemplate a series of interesting facts and structures, as well as to promote a good understanding of properties suitable to be worked on in more contexts. The text also deals with the set of Gaussian integers, which is still not so often worked on, but presents an interesting potential for studying integers.
Desenvolvimento inicial de seleções de lima ácida tahiti em diferentes porta-enxertos sob condições irrigadas e não irrigadas
(Universidade Federal de São Carlos, 2021-11-25) Oliveira, Rebeca Espíndola de; Schinor, Evandro Henrique; https://lattes.cnpq.br/2162760988837984; Bizari, Douglas Roberto; https://lattes.cnpq.br/0558728017553792; https://lattes.cnpq.br/1741472136419365
Brazil is one of the largest citrus producers in the world and is a major producer of limes and lemons, especially the production of Tahiti acid lime. The Brazilian citrus industry represents great economic and social importance and the selection of new materials, both varieties and rootstocks, such as dwarfing rootstocks, have allowed the implantation Higher planting densitie , allowing productivity gains in citrus orchards. Furthermore, the use of irrigation generates a series of benefits to production, affecting both the characteristics of vegetative development and reproductive stage of the plant. Thus, the objective of this work was to evaluate the initial development of different Tahiti lime scion/rootstock combinations under different drip irrigation management and dryland farming. For this, in March 2020, seedlings of Tahiti acid lime of five different combinations scion/rootstock were planted and submitted to two irrigation treatments and one dryland farming. The experimental design was in randomized blocks in a split-plot scheme. The diameter of rootstock , height, canopy volume, canopy diameter, Coverage Rate in the tree-Row (TCCL), Coverage Rate in the tree Inter- row (TCCE) and Vegetative Vigor Index were evaluated ( IVV), as well as the growth of plants during the first year after planting. The results were submitted to analysis of variance (ANOVA) and the Scott-Knott test (5%). From the statistical analysis, it was possible to verify that the combinations BRS Ponta Firme/FD and IAC 10/152 presented the highest plant height values, diameter of scion, volume of scion, TCCE, TCCL and IVV, compared to the others. The H228, H14 citrandarin and the Flying Dragon trifoliate, when grafted with the IAC 10 canopy, induced the formation of smaller plants, with smaller canopy volume and less vigor. There was no significant difference between the irrigated and non-irrigated treatments, however it was possible to observe some differences in height growth over time. For some scion/rootstock combinations, both management of irrigation resulted in greater height, compared to the non-irrigated treatment, indicating the rootstocks with greater response to irrigation management.
Tubos em compósito de epóxi reforçado com fibra de vidro produzidos pelo processo de enrolamento filamentar para aplicação na indústria petroquímica
(Universidade Federal de São Carlos, 2021-11-25) Guiguer, Elton Landgraf; Sousa, José Alexandrino de; https://lattes.cnpq.br/7737833809468759; https://orcid.org/0009-0007-7863-7043; Canto, Leonardo Bresciani; https://lattes.cnpq.br/7287108960864123; https://orcid.org/0000-0002-4138-005X; https://lattes.cnpq.br/9145964638323755; https://orcid.org/0009-0006-7000-2329
This work is focused on the production and mechanical performance evaluation of filament-wound flat plates and pipes using different composite compositions of three distinct commercial high glass transition epoxy resins reinforced with glass fiber (GRE) in order to verify their potential usage in the petrochemical industry. The evaluation included measurements of the glass transition temperature, Tg, of the epoxy matrix resins through Dynamic Mechanical Analysis (DMA) and by Differential Scanning Calorimetry (DSC) for the produced GRE composites tubes. Also, the mechanical performance of these different GRE composites was analyzed through mechanical tensile, shear, flexural and impact strength properties using current materials testing standards. The mechanical properties results were compared with their theoretical values calculated using the simple rule of mixtures equations. Furthermore, a pipe was designed using the classical laminate theory analysis and samples were produced and tested according to the API 15 burst test standard. The evaluation of fiber/resin interfacial compatibility was investigated by scanning electronic microscopy analysis in order to correlate the interfacial adhesion with the obtained mechanical properties. The experimental results are close to the foresee values for Tg and mechanical results, in the second case considering the coupons production process limitations. This screening project showed potential usage glass fiber reinforced epoxy pipes for oil extraction production columns in the undersea pre-salt regions. Evidently, it is necessary to further investigate more deeply into the subject before an installation of such GRE tubes are reliable enough for use under the severe operation conditions in the short, medium and long term.
Características luminescentes do sistema relaxor PLMN-13PT dopado com érbio em transições de fase polar
(Universidade Federal de São Carlos, 2021-11-25) Correr, Guilherme Ilário; Garcia, Ducinei; https://lattes.cnpq.br/5236758856687873; Godoy, Marcio Peron Franco de; https://lattes.cnpq.br/2609654784637427; https://lattes.cnpq.br/0275011309080626
Structural and polar phase transitions are important for materials studies, specially for normal and relaxor ferroelectrics. These states influence the materials physical characteristics, which are observable by many characterization techniques. In this context, the main objective of this monograph was the study of luminescent characteristics of the relaxor ferroelectric ceramic system PLMN-13PT doped with trivalent Erbium ions, when influenced by temperature and electric field changes, highlighting polar state transitions. Our results show the parameters as the amplitude and peak position of Erbium emissions (excited by Er-resonant 442 nm wavelength) by six conditions of electric field and temperature. From dipole glass model theory for relaxor ferroeletrics, and assuming the existence of polar nanorregions (PNR), changes in emission are related to electric field dependence and some anomalies are observed, mainly next to the freezing relaxor transition temperature.
Estudo numérico e experimental das rigidezes de contato de uma estrutura de espelho da linha Mogno do Sirius
(Universidade Federal de São Carlos, 2021-11-25) Silva, Dante Vecchia Rocha; Araujo, Luis Antonio Oliveira; https://lattes.cnpq.br/3639906702064630
One of the challenges in the project of new 4th generation synchrotron light sources, such as Sirius (LNLS), is the design of the mechanical stability of the components of the new beamlines, where it is possible to carry out experiments with nanometer sized light beams. With the existence of mechanical vibrations inherent to the process in all its stages, it is necessary to reduce its effects as much as possible, as they directly affect the beam stability and may cause a loss of beamline resolution. A crucial step in the stability assessment is the modal analysis, in which it is important to know and use adequate contact stiffness values to ensure the quality of the design. As it is a complex concept and dependent on several factors, such as material stiffness, contact roughness, body bond strength, surface quality, among others, it is difficult to obtain analytically reliable results and even to replicate studies carried out in different projects. Therefore, the purpose of this study is to acquire the coherent values of the contact stiffnesses of one of the mirror structures of the Mogno Line, which is being projected to be the world leader in micro and nano images using X-rays, through a methodology that combines an experimental modal analysis of the system with a numerical optimization study using the Ansys program. Finally, identify the most sensitive contacts for the system and propose changes in geometries to improve mechanical stability. The values found in this work can be used in beamline projects in the future. Keyword: Contact Stiffness. Sirius. Mechanical Vibrations. Model Updating.
Utilização do modelo pictórico da Matemática de Singapura em resoluções de problemas para os 5o e 6o anos do ensino fundamental, dentro da proposta curricular do estado de São Paulo
(Universidade Federal de São Carlos, 2021-11-25) Sprovieri, Luis Henrique; Baldin, Yuriko Yamamoto; https://lattes.cnpq.br/8785562528979416; https://lattes.cnpq.br/3537532707019356
Teaching mathematics is a challenge for both educators and students. It is usual to notice the lack of interest of students in Mathematics, especially when it is associated with letters and symbols, missing its real meaning. But this lack of interest usually appears exactly in the transition between cycles I and II of elementary school, specifically between the 5th and 6th grades. The cycle transition is also the transition between “Concrete” Mathematics, with manipulative materials, and “Abstract” Mathematics, with its symbols and its own language. The work presents the use of a pictorial model of Singapore Mathematics, called the Bar Model, in order to ease and make the passage of cycles satisfactory, thus creating a bridge between the concrete and the abstract in order to alleviate the difficulties of students in this transition. For this purpose, problem situations for the 5th and 6th years were selected from the State’s official instructional material in accordance with the curricular proposal. These were developed using the Bar Model methodology.
Atores chave na mitigação de riscos em recall de alimentos: quem são e principais papéis
(Universidade Federal de São Carlos, 2021-11-25) Santos, Julia de Oliveira; Silva, Andrea Lago da; https://lattes.cnpq.br/2380499339281186
Close cooperation between stakeholders in the supply chain, in order to prepare the planning for risk mitigation in a holistic and integrated manner, can prevent the occurrence of risks in the supply chain. Risk prevention is of fundamental importance in the food supply chain, as it gives rise to a likelihood of food contamination, increasing its safety. If the commercialized food presents any risk to the consumer's health, the product must be removed immediately. A food recall occurs when a company removes its products from the market due to concerns that the product may negatively affect consumer health (POTTER et al., 2012). This study aims to understand who the stakeholders in the food supply chain are and what their main roles are in mitigating food recall risks. To achieve its objective, a dissertation using two research methodologies, a systematic literature review (SLR) and a case study. A total of 9 stakeholders and 55 mitigation actions were identified. Although there are researches on how stakeholder actions can mitigate food recall events, they focused on one or more stakeholders, neglecting the others. One contribution of this work was to develop a model that presents all stakeholders involved in recall events and their actions.
Eficiência do tratamento de sementes para controle de Dalbulus maidis (DeLong & Wolcott) na cultura do milho: uma revisão bibliográfica
(Universidade Federal de São Carlos, 2021-11-25) Gonçalves, João Matheus; Marques, Rodrigo Neves; https://lattes.cnpq.br/8945237946471247; https://lattes.cnpq.br/0743592650628966
Maize is one of the most important agribusiness crops in Brazil. As it is produced in three harvests, it contributes to prolonged periods of survival of the corn leafhopper, Dalbulus maidis (DeLong & Wolcott), one of the main pests of the crop. The damage caused by this pest is mainly the transmission of phytopathogenic bacteria, phytoplasma and spiroplasma, and the transmission of the Maize Rayado Fino Virus when feeding on plant sap, which drastically affects crop productivity. The control of this pest is carried out mainly with chemicals, and can be done in the form of seed treatment with systemic insecticides, and its use has gained ground in the market for achieving higher productivity in crops. Insecticides used in seed treatment act preventively in the control of D. maidis, preventing major damage in the early stages and ensuring the development of maize plants. This work addressed a literature review of recent studies evaluating the effectiveness of seed treatments to control D. maidis in maize crops and also the effect of these treatments on stunt-disseminating pathogens. In order to complement the work, due to the lack of studies on the effectiveness of seed treatment for the control of D. maidis in the maize crop, works referring to the control of other sucking insects in the cotton crop, using the seed treatment were addressed. Seed treatment is efficient in the control of sucking insects in the initial stages of the culture in experiments carried out in greenhouses, as a preventive strategy. Under field conditions, the results were unsatisfactory. Thus, the need for further studies on the efficiency of seed treatment for the control of D. maidis in maize crop is evident.
Rotas de exposição aos micro e nanoplásticos e suas consequências para a saúde humana
(Universidade Federal de São Carlos, 2021-11-25) Makiyama, Victória Akemi; Urban, Roberta Cerasi; https://lattes.cnpq.br/7313670290572985
The use of plastics has brought several advances mainly related to medical and food biosafety; however, it has become an environmental problem, due to inadequate disposal. These residues accumulate in environments, making them susceptible to fragmentation mechanisms, originating microplastics (MPs) and nanoplastics (NPs). These, resulting from the fragmentation of macroplastics, can be classified as secondary, and those produced in reduced size are primary MPs and NPs. Humans are exposed to macroplastics, microplastics and nanoplastics via ingestion, inhalation, and dermal contact, which will be discussed in this work. Exposure via ingestion can occur in the consumption of food, such as sugar, honey, table salt, and seafood; and also in the consumption of bottled and tap water, and can reach 52,000 particles of MPs ingested annually. Inhalation is the most important route of exposure, and can reach 30,000,000 MPs inhaled annually, due to the concentrations of MPs in the atmosphere. Exposure via dermal contact is related to the use of cosmetics with plastic microspheres, or due to the MPs present in water. MPs and NPs can have several consequences for human health, for example: acting as carriers of microorganisms and toxic species, oxidative stress, apoptosis, inflammation, cytotoxicity, interference with homeostasis, metabolism, and immune system, translocation and neurotoxicity. Occupational diseases resulting from exposure to plastic materials were also reported. Although the indiscriminate use of plastic has negative impact on the environment and on humans, its use continues to grow. This makes it necessary to implement harm reduction policies and programs, such as the concept of the 5Rs.
Estudo de viabilidade da espectrocospia de infravemelho próximo para pagamento de cana por teor de sacarose
(Universidade Federal de São Carlos, 2021-11-25) Pereira, Beatriz Benassi; Carneiro, Renato Lajarim; https://lattes.cnpq.br/8065852319463976; https://lattes.cnpq.br/0553431539124344
This study was developed in a sugarcane industry, in a sugarcane payment laboratory by sucrose content, where the payment of sugarcane is determined through analytical parameters such as Brix degree, Pol reading, fiber content, among others. The determination of these parameters is made by instrumental measurements that require intense operator attention. Thus, the purpose of this study is to demonstrate an improvement in the process, with the replacement of the conventional method, which requires a lot of labor and consumable materials, through the use of a near infrared spectrophotometer (NIR, near, infrared) coupled with the automation method. These models would be used to more quickly and cost-effectively predict the values of previously reported analytical parameters. The observed results showed that the use of NIR equipment is certified as a robust method for analyzing sugarcane, increasing the sampling of the raw material, ensuring reliable analytical results for the payment of sugarcane and with better economic viability when compared to the conventional method.
Planejamento da expansão de sistemas de transmissão de energia elétrica baseado na relaxação sigmoidal de variáveis de decisão binárias e análise de sensibilidade por multiplicadores de Lagrange
(Universidade Federal de São Carlos, 2021-11-25) Portela, Guilherme Leonidas Santana; Lage, Guilherme Guimarães; https://lattes.cnpq.br/4426242038269208; https://lattes.cnpq.br/4002881208401969
This paper presents the development of a heuristic algorithm to solve the Transmission System Expansion Planning (TSEP) problem. The binary decision variables associated with the decision to build transmission lines in the PEST problem are modeled by the image of a sigmoidal function, transforming the original Mixed Integer Nonlinear Programming (MINLP) problem into an equivalent Nonlinear Programming (NLP) problem whose local optima coincide with the feasible region of the original problem, allowing the use of commercial NLP solvers. In the proposed heuristic algorithm, the final investment plan is obtained after successive PEST resolutions with the sigmoidal relaxation of the binary expansion decision variables, followed by the accommodation of the relaxed solution into a mixed integer solution based on local sensitivity analysis by Lagrange multipliers. Moreover, reference data from the National Electric Energy Agency (ANEEL) are used to define the unit cost of expansion of the candidate transmission lines. The effectiveness of the developed heuristic algorithm is demonstrated through its application to Garver 6-bus, 24-bus IEEE and 46-bus South Brazilian systems.
Requisitos e percepções do público universitário sobre os serviços de drive thru sob os efeitos da pandemia do COVID-19
(Universidade Federal de São Carlos, 2021-11-25) Gomes, Natal Lenartevitz; Silva, João Eduardo Azevedo Ramos da; https://lattes.cnpq.br/3823047207711289; https://orcid.org/0000-0002-6739-5065
The pandemic caused by COVID-19 has changed the way in which goods and services are offered. The need for social isolation has expanded systems with minimal contact between suppliers and customers, such as drive thrus systems. This research has as general objective to study the perceptions of the university public about the drive thru service under the effects of the SARS-Cov-2 virus pandemic and its expansion to new segments, and to compare the service before and after the beginning of the pandemic. The requirements for good service provision in this format are raised and how users' perceptions differ between two moments: before and after the start of the COVID-19 pandemic. The data survey was carried out with online questionnaires, using the SERVQUAL methodology, sent to the public at the Federal University of São Carlos - Campus de Sorocaba, in order to evaluate drive thru services in that city. With the results obtained, it is demonstrated that the users' expectations are higher than the perception in all the analyzed questions, following a relatively small negative satisfaction. Furthermore, it is concluded that, even not fully meeting the expectations of users, the implementation of the drive thru service appears as an alternative to keep companies operating, while respecting the restrictive measures to combat COVID-19.
Teorema Fundamental do Cálculo: uma proposta de abordagem a partir da modelagem matemática com auxílio do Geogebra
(Universidade Federal de São Carlos, 2021-11-25) Marco, Maria Laura De Biaggi de; Pires, Rogério Fernando; https://lattes.cnpq.br/2795801064535157; https://lattes.cnpq.br/2122253331416681
The disciplines Differential and Integral Calculus for STEM students require a precise understanding of the themes to avoid it being an arduous path of learning and building a solid foundation, and it is the teacher's responsibility in their teaching process for the best options. This paper aims to present an approach to the Fundamental Theorem of Calculus, but specifically, applications of integrals and assumptions of mathematical modeling, using technological resources. For this purpose, a study of a historical-epistemological nature was carried out in an attempt to understand how this concept has developed throughout history, from the Ancient Age to Newton and Leibniz, who arrived at the Fundamental Theorem or derivation as inverse operations. Next, carried out a study on the use of mathematical modeling as a teaching methodology following the assumptions of Biembengut and Hein (2019), Bassanezi (2015), and Bassanezi (2018). And finally, two sequences of activities based on assumptions of mathematical modeling were elaborated. Sequence 1 was developed to achieve the calculation of the area of an image of a lake and sequence 2 was elaborated to provide a road map for the calculation of the volume of an image of glass. In both, the development of the solution was carried out according to the steps of the mathematical shaping and modeling process and had the GeoGebra software as a calculation tool.
La muerte
(Universidade Federal de São Carlos, 2021-11-25) Melo, Isabela Maria Aguiar de; Silva, Lucas Perossi Sampaio de Campos Marques da; Jacinto, Matheus; Oliveira, Murilo Morais; Salvi, Pietro Mitestainer de; Moraes, Stephano Andrade de; Miranda, Vinicius de Souza; Burini, Débora; https://lattes.cnpq.br/3581804746301862; https://lattes.cnpq.br/9126242794466352; https://lattes.cnpq.br/8732754885840920; https://lattes.cnpq.br/9062119880902588; https://lattes.cnpq.br/6272899555202277; https://lattes.cnpq.br/2076646123409466; https://lattes.cnpq.br/4299928636505983; https://lattes.cnpq.br/7636440167834939
This report intends to present the group final project to the Image and Sound graduation, under the guidance of Profa. Débora Burini. The project entitled ‘La Muerte’ is the product of the development of two other audiovisual projects between the years of 2019 and 2020, both unable to be carried out due to the pandemic context that our country is in. Our video aimed to imagetically translate reflections on the themes of death, the passage of time and life, linked to a poem that supports the discourse. Here is the necessary information to understand our project, including a presentation of La Muerte, its synopsis, argument, script and conceptual proposal, as well as technical information.