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Análise e modelagem de vibrações auto-excitadas no processo de torneamento de ligas de titânio por elementos finitosa
(Universidade Federal de São Carlos, 2023-04-13) Degan, Bruno Zambrano; Shiki, Sidney Bruce; https://lattes.cnpq.br/0573973677787523; https://lattes.cnpq.br/2561715399174989
A critical parameter in machining processes is the final surface quality of the machined part, directly related to self-excited vibrations that arise in these processes due to the interaction between the cutting tool and the surface, thus impairing the final roughness obtained and intensifying the wear of the machining tool. cut. Thus, it becomes interesting to model these vibrations to obtain ideal ranges of cutting parameters, especially machining depth and rotation, ensuring better productivity without jeopardizing the surface quality of the machined parts. In the present work it is proposed, through the finite element method, the modeling of the self-excited vibrations in the turning process of titanium alloys, aiming at the creation of stability lobe diagrams through frequency response functions and machining constants, in order to evaluate the degree of influence of superior vibration modes on the stability diagrams and to allow an integration between the finite element model and a model for calculating the stability of the processes.
Embalagens ativas e inteligentes: tendências e projeções
(Universidade Federal de São Carlos, 2023-04-13) Cândido, Antônio Henrique Melo; Freire, Fábio Bentes; https://lattes.cnpq.br/8937961078558996
Packaging is a technique that involves wrapping or protecting products for distribution, storage, commercialization, and use. In addition to containing the product, packaging also identifies, describes, protects, displays, promotes, and maintains properties and quality. Food packaging can be specifically defined as the packaging that protects against physical, chemical, and biological sources of contamination or adulteration. Active and intelligent packaging are two forms of commercialization that have the primary role of extending the shelf life of food products, thus reducing losses from expired or spoiled food. Unlike conventional packaging, active packaging employs technology that intentionally releases or absorbs compounds from the food or the free space in the packaging, thereby extending the products' shelf life by interrupting degradative reactions such as lipid oxidation, microbial growth, and moisture gain and loss. Intelligent packaging, on the other hand, communicates with consumers and other intermediaries throughout the entire commercialization chain. It is estimated that these two types of packaging will drive this sector, as the number of the world's population exceeds eight billion, and smart strategies for the production, distribution, and commercialization of food products become essential for society's development in the 21st century. The objective of this undergraduate thesis was to describe the current status of active and intelligent packaging within the food sector, highlighting the types already in use, and relate their functioning mechanisms to chemical engineering. Through a comparative contextualization between conventional and intelligent packaging, we sought to identify economically viable application trends that project the future of this form of food commercialization.
Theoretical and experimental investigation on the visible-light controlled functional properties in charged domain wall ferroelectrics
(Universidade Federal de São Carlos, 2023-04-13) Pimentel, Jonathan Ordoñez; García, Jose Eduardo; https://orcid.org/0000-0002-1232-1739; Venet Zambrano, Michel; https://lattes.cnpq.br/4256279833398263; https://orcid.org/0000-0002-0969-4999; https://lattes.cnpq.br/6513891083706993; https://orcid.org/0000-0003-1065-5775
Optical control of ferroelectric properties have been attracted a growing interest as an alternative to the conventional control by applied electric fields. However, the major drawback for achieving an effective reversible optical control of domain rearrangement in conventional ferroelectrics lies in their wide optical band gap. Recent researches have reported a new form to optically control of electric polarization and its related properties by using visible light. Specifically, a light-induced local movement of domain walls was achieved, whose effects shown that the photoresponse at both local and macroscopic scales is wavelength-independent. This new phenomenon of light-matter coupling has a non-negligible time response and no light power threshold was observed. Such characteristics are observed through the crystal lattice structure, photo-induced strain and dielectric permittivity. In addition, experimental evidences suggest that the light-activated phenomenon seems to be correlated with the existence of atypical ferroelectric interfaces, known as charged domain walls, whose principal signature is to host free and bound electric charge. Undoubtedly, this phenomenon offers new possibilities for technological applications that are as yet unexplored. This thesis focuses in overcome some questions that remains to be solved concerning to this light-activated phenomenon. That is: What is the physical insight about the photo-ferroelectric response? Is the extension towards polycrystalline materials feasible? Are there other physical properties different from those already controlled enable to be modified? To answer these question, the thesis divides into two parts: one theoretical and another one experimental. In the first part, a phenomenology model describing the visible light-induced photoresponse is developed, which assumes that visible light modifies charged domain wall compensation so that the built-in electric fields in the system changes, thereby triggering the domain wall motion. As a result, a rearrangement of the domain structure occurs, leading to a macroscopic polarization variation and, consequently, the related properties. Regarding to extension towards polycrystalline materials, it is successfully proved that photoresponse can be observed by the optical control of the photo-induced strain. Furthermore, it is proved the hypothesis that the existence of charged domain walls is a requirement for the photoresponse to manifest. Finally, the thesis reports for first time that the mechanical response of a ferrolectric ceramics can be modulated by visible light, highlighting the role of the charged domain walls. In a broader perspective, this work contributes to extending the fundamental knowledge based on light-ferroelectric coupling, opening new opportunities to speed up the development of a new generation of contact-less photoelectronic devices.
Contribuições formativas da educação tutorial no ensino de graduação: relato das experiências do Grupo PET BCI/UFSCar
(Universidade Federal de São Carlos, 2023-04-13) Lourenço, Adriano Ruda Gabriel; Dal'Evedove, Paula Regina; https://lattes.cnpq.br/1170937498266968
The Tutorial Education Program, implemented by the Federal Government, encourages the development of teaching, research and extension activities at the undergraduate level in Higher Education Institutions in the country. In view of the importance and scope of tutorial education, the aim is to identify the contribution of the Tutorial Education Program (PET), more specifically its impact on Librarianship and Information Science courses, by reporting the experiences of the PET BCI Group at the Federal University of São Carlos (PET BCI/UFSCar). To this end, concepts and principles of tutorial education will be addressed, the role of tutorial education in the training of librarians and information scientists, as well as the experiences of PETs in library science in Brazil, with a focus on the historical path of PET BCI from UFSCar. It is an exploratory and descriptive research, conducted through bibliographical research and survey in environments maintained by the groups. As a result, there are benefits for the training of future librarians and information scientists in the personal, professional and general scope, with the PET BCI of UFSCar being a prominent group on the national scene.
Tendências de pesquisa em Informação & Saúde no Brasil: análise do GT 11 do ENANCIB
(Universidade Federal de São Carlos, 2023-04-13) Sampaio, Hibari Sebin; Dal'Evedove, Paula Regina; https://lattes.cnpq.br/1170937498266968
With the growth of scientific production in health, the librarian's contribu-tion has proven to be indispensable for the treatment and availability of information in this area, in the face of the circulation of untrue infor-mation about health. From this perspective, information science plays a fundamental role in the creation and availability of informational products and services in the context of health that offer professionals in the field and citizens mechanisms capable of acting assertively. Therefore, the question arises what are the research trends in information and health in Brazil? In order to contribute to the subject, the objective is to outline the profile of the publications presented in GT11 in the last five editions of ENANCIB, through the following research activities: present the insertion of health in Brazilian information science; map the scientific production of GT11 for the years 2017, 2018, 2019, 2021 and 2022; and discuss the profile of scientific research in the field of information related to infor-mation and health, based on GT11. This is an exploratory and descriptive research, with a qualitative and quantitative approach to the data. As a result, there were a total of 65 publications presented in the period, dis-tributed across five investigative axes, presented by 116 authors from 33 public and private sector institutions; with emphasis on issues linked to health information policies. It is concluded that the investigative axis is active and offers important paths for establishing actions that promote and support health information, as a guarantee of personal, collective and global development.
O desafio das igrejas se fazerem inclusivas em face da grande apostasia juvenil
(Universidade Federal de São Carlos, 2023-04-13) Silva, Daniel Kayan Sirtori Felix Lopes da; Souza, André Ricardo de; https://lattes.cnpq.br/7016915324466152
The purpose of this study is to expose and analyze the facts that leave the new generations in conflict, bringing inclusion into the churches, so that they don't get along and end up abandoning their beliefs. To this end, quotes and opinions from various authors on the subject were used, as well as the author's point of view through his experience in the field. The main objective of the work was to analyze the reasons for apostasy among young people in the church, examining why they have become more inclusive and their new nuances. The secondary objectives included conceptualizing and delimiting the new generations of believers and non-believers, studying the friction between them and understanding the churches' methods of reaching them. The methodology used was a bibliographical review, using books, articles and websites.
People s awareness of circular economy: scale development and relationship with social influence, psychological barriers, and favourable evaluation of sustainable development
(Universidade Federal de São Carlos, 2023-04-13) Gonella, Jéssica dos Santos Leite; Godinho Filho, Moacir; https://lattes.cnpq.br/6136685270563354; https://orcid.org/0000-0001-6150-1333; https://lattes.cnpq.br/4855895070018631; https://orcid.org/0000-0001-8741-4510
Circular Economy (CE) encompasses strategies that aim to decouple economic activity from finite resource consumption and eliminate waste from the system as a matter of principle. Supported by a transition to renewable energy sources, the circular model builds economic, natural, and social capital through three principles: eliminate waste and pollution from the start; keep products and materials in use in the supply chain; and regenerate natural systems. The transition to a CE must be initiated by a paradigm shift in the entire supply chain including people. Although this topic is being addressed in several research studies around the world, there are still some research gaps to be filled: (i) Lack of research that considers the analysis of the CE from the perspective of people (bottom-up level), without standardizing on the position these actors occupy in the value chain or the social context in which they are inserted; (ii) the level of depth that CE strategies are dealt with, since the literature points to studies that address specific strategies individually, without delving into the plurality that configures CE; (iii) a lack of a measurement scale to measure people's awareness of CE; (vi) lack of studies in the Brazilian context. Thus, this thesis aims to analyse the factors that interact with people's awareness of CE and their effects on people's favourable evaluation of sustainable development. First, we conducted a Systematic Literature Review (SLR) to map the literature on CE studies. Second, we built and validate a measurement scale to evaluate people’s awareness of CE. After that, we used the validated measurement scale to test two theoretical models. The first presented as its objective assess the effect of Social Influence and Psychological Barriers on People's Awareness of CE. To support our theoretical model and to ground the constructs, we sought inspiration from the Theory of Behavioral Choice (TBC). The second, aimed the analyse the relationship between people's awareness of CE and Favourable Evaluation of people concerning the importance of efforts for sustainable development. To support this theoretical model, we sought inspiration from the Social Learning Theory, which suggests that people learn from their environment and the behaviours of others around them. A survey was applied to 1046 Brazilian respondents through non-probability sampling, and multivariate data techniques (PLS-SEM) were applied. The results of the first model showed that Psychological Barriers (Sunk Costs dragons and Limited Cognition dragons) restrict people's awareness of CE. Besides, it was found that Social Influence (family, friends, and celebrities) positively influence people's awareness of CE. The findings indicate that Social Influence mitigates the negative effect of Psychological Barriers on People's Awareness of CE. The results of the second model showed that people Awareness of CE positively influences favourable evaluation about the importance of Sustainable Development, and the engagement of people and the participation of institutions on Sustainable Development efforts.