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The main objective of this paper is to Identify which macroe conomic factors and industrial indexes influenced the total Brazilian banking spread between March 2011 and March 2015. This paper considers subclassification of industrial activities in Brazil. Monthly time series data were used in multivariate linear regression models using Eviews (7.0). Eighteen variables were considered as candidates to be determinants. Variables which positively influenced bank spread are; Default, IPIs (Industrial Production Indexes) for capital goods, intermediate goods, du rable consumer goods, semi-durable and non-durable goods, the Selic, GDP, unemployment rate and EMBI +. Variables which influence negatively are; Consumer and general consumer goods IPIs, IPCA, the balance of the loan portfolio and the retail sales index. A p-value of 05% was considered. The main conclusion of this work is that the progress of industry, job creation and consumption can reduce bank spread. Keywords: Credit. Bank spread. Macroeconomics. Industrial Production Indexes. Finance., Comment: in Portuguese langauge. Keywords: Credit. Bank spread. Macroeconomics. Industrial Production Indexes. Finance

A new system, called SELA -- Auditing Electronic System, has been developed to be applied to the Brazilian Electronic Voting Machine. The SELA was designed to use open hardware and software, making it widely known by society. The security of the auditing process is guaranteed by the application of a Fingerprint Algorithm, a Hash Function. This system is robust and requires minimal modifications to the Electronic Voting Machine. In this paper, SELA is described, and its use during the election process is analyzed. A comparison between SELA and the use of thermal printers as a secondary voting record system is also presented. The authors recommend a pilot implementation of SELA for the 2002 Brazilian Elections., Comment: 7 pages, in Portuguese language, 3 figures, prototype

Women and gender-diverse people represent an important constituency in the food value chain. Among all working women globally, about one in three works upstream in the food value chain. These women face increasing barriers to safety, recognition and advancement. Yet very little about their experiences has been documented. In the limited instances where the women who power global supply chains have been put into focus, most have concentrated on the experiences of women workers in the apparel sector., Through desktop research, one-on-one interviews with local organizations, case studies and workshops, this paper provides information and guidance on how investors, who are well-positioned to encourage companies to advance gender equity upstream in company supply chains, can help reshape this narrative and encourage companies to act.

In this paper, we propose the replication of scientific experiments, with the participation of the general public, as one of the possible strategies to confront science deniers. Using the social media of the Federal University of Lavras (UFLA), the project entitled : The Magic of Physics and the Universe, invited the public to reproduce the experiment carried out by the Greek Eratosthenes over 2,100 years ago, which he proved that the Earth is spherical. We present a report of this experience to suggest that it is possible for citizens to experience scientific knowledge and observe the phenomena in a simple way, in order to develop a critical interpretation of false information that circulates in society. This proposal distinctively geeks to deconstruct the denial of the Earth's curvature through direct and collective participation of citizens in Eratosthenes' experiment, which permit more reflection on how the scientific method used to study this subject works., Comment: This article is written in Portuguese

This paper analyzes the redistributive impacts of indirect taxation reforms in Brazil inspired by PEC 45/2019, particularly in the version that led to EC 132/2023. Comparisons are made between the current system and the simulated reforms, considering the distribution of the tax burden among families in different income classes, as well as the impact on poverty and inequality indicators. The simulations are conducted based on the combination of effective tax rates that apply to goods and services consumed by households, using nationally representative microdata from family budgets., Comment: in Portuguese language

This study aims to discuss the impacts of a low-cost airline on the air transport market and, especially, to present the most recent findings from specialized literature in the field. To this end, various works on this topic, published since 2015, were selected and analyzed. From this analysis, it was possible to categorize the main topics discussed in the papers into five groups: (i) the impacts of a low-cost airline on competing airlines; (ii) impacts on airports; (iii) general impacts on the demand for air transport; (iv) effects on passengers' choice process; and (v) general effects on a geographical region., Comment: This article is written in Portuguese

We discuss how to extract numerically the expected lowest quasi-normal mode (QNM) associated with the pressure anisotropy for a Bjorken flux evolution to equilibrium. This QNM was easily decoded subtracting the hydrodynamical attractors and was compared with other authors calculations. After evolutions with transients close to the expected lowest QNM the system goes to a tail (pure imaginary frequency) for late times. We analyze the relevance of Navier-Stokes, second order and Borel attractors at each stage of the evolution, which begins far-from-equilibrium and ends close to equilibrium., Comment: 7 pages, 6 figures; revised version; title, abstract and keywords added in Portuguese

This study presents a comprehensive methodology for modeling and forecasting the historical time series of active fire spots detected by the AQUA\_M-T satellite in the Amazon, Brazil. The approach employs a mixed Recurrent Neural Network (RNN) model, combining Long Short-Term Memory (LSTM) and Gated Recurrent Unit (GRU) architectures to predict the monthly accumulations of daily detected active fire spots. Data analysis revealed a consistent seasonality over time, with annual maximum and minimum values tending to repeat at the same periods each year. The primary objective is to verify whether the forecasts capture this inherent seasonality through machine learning techniques. The methodology involved careful data preparation, model configuration, and training using cross-validation with two seeds, ensuring that the data generalizes well to both the test and validation sets for both seeds. The results indicate that the combined LSTM and GRU model delivers excellent forecasting performance, demonstrating its effectiveness in capturing complex temporal patterns and modeling the observed time series. This research significantly contributes to the application of deep learning techniques in environmental monitoring, specifically in forecasting active fire spots. The proposed approach highlights the potential for adaptation to other time series forecasting challenges, opening new opportunities for research and development in machine learning and prediction of natural phenomena. Keywords: Time Series Forecasting; Recurrent Neural Networks; Deep Learning., Comment: 16 pages and 24 figures, in Portuguese language

Non-linear dynamics is not a usually covered topic in undergraduate physics courses. However, its importance within classical mechanics and the general theory of dynamical systems is unquestionable. In this work we show that this subject can be included in the schedule of an introductory classical mechanics course without the need to develop a robust theory of chaotic dynamics. To do this, we take as examples conservative non-linear oscillators subject to time-dependent periodic forces. By introducing the concept of stroboscopic maps we show that it is possible to visualize the appearance of chaos in these systems. We also address the example of the forced simple pendulum applying the same treatment. Finally, we briefly comment on the more general theory of chaos in conservative Hamiltonian systems., Comment: 14 pages, 16 figures. Accepted for publication in "Revista Brasileira de Ensino de F\'isica". Written in Portuguese

Under extreme conditions of temperature and pressure, it is believed that quarks and gluons (particles that mediate the interaction between quarks) can be "free" in a given volume. This hypothetical phase of matter is called plasma of quarks and gluons, QGP for its acronym in English. It is speculated that it existed in the first moments after the \textit{Big Bang} and that it exists inside N\^eutron stars due to the enormous energy density in these places. These conditions of very high temperature and energy density can be reproduced in the laboratory with the collision of heavy ions in an ultra-relativistic regime in accelerators such as the RHIC and the LHC. However, due to the extremely short duration of the QGP phase after the collision, we were unable to directly observe the plasma, only the so-called \textit{final observables}, such as the particles generated by this set of quarks, gluons and energy and the distribution of momentum of these particles. Therefore, mathematical modeling is an essential tool in understanding the behavior of the system, for example, to have an idea of the value of viscosities in this phase., Comment: 9 pages, in Portuguese language

The covariance of the d'Alembert equation for acoustic phenomena, described by mechanical waves in one or three spatial dimensions, under Galilean transformations, is demonstrated without the need to abandon the hypothesis that time is absolute in Classical Mechanics. This is true only if and only if the phase velocity of sound depends on the velocity of the observer. On the other hand, it is also shown that the same d'Alembert equation is covariant under Lorentz transformations if and only if the phase velocity of light does not depend on the observer., Comment: 11 pages, in Portuguese

The Pythagorean Theorem is one of the oldest, more famous and more useful theorems of Mathematics, and possibly the one that has had the most impact in the evolution of this and other sciences. In this article, we look at it from different perpectives, some of them uncommon. We recall some of its history, some well known applications and generalizations, other less known ones, and show it still has many surprising facets which are usually ignored. (O Teorema de Pit\'agoras (TP) \'e um dos mais antigos, famosos e \'uteis teoremas da Matem\'atica, e possivelmente o que maior impacto teve na evolu\c{c}\~ao desta e outras ci\^encias. Neste artigo, vamos olhar para este velho conhecido de diferentes perspectivas, algumas pouco usuais. Iremos lembrar um pouco da sua hist\'oria, algumas aplica\c{c}\~oes e generaliza\c{c}\~oes bem conhecidas, outras nem tanto, e ver que ele guarda muitas facetas surpreendentes e geralmente ignoradas.), Comment: in Portuguese language

Considering a pair of genomes, the goal of rearrangement distance problems is to estimate how distant these genomes are from each other based on genome rearrangements. Seminal works in genome rearrangements assumed that both genomes being compared have the same set of genes (balanced genomes) and, furthermore, only the relative order of genes and their orientations, when they are known, are used in the mathematical representation of the genomes. In this case, the genomes are represented as permutations, originating the Sorting Permutations by Rearrangements problems. The main problems of Sorting Permutations by Rearrangements considered DCJs, reversals, transpositions, or the combination of both reversals and transpositions, and these problems have their complexity known. Besides these problems, other ones were studied involving the combination of transpositions with one or more of the following rearrangements: transreversals, revrevs, and reversals. Although there are approximation results for these problems, their complexity remained open. Some of the results of this thesis are the complexity proofs for these problems. Furthermore, we present a new 1.375-approximation algorithm, which has better time complexity, for the Sorting Permutations by Transpositions. When considering unbalanced genomes, it is necessary to use insertions and deletions to transform one genome into another. In this thesis, we studied Rearrangement Distance problems on unbalanced genomes considering only gene order and their orientations (when they are known), as well as Intergenic Rearrangement Distance problems, which incorporate the information regarding the size distribution of intergenic regions, besides the use of gene order and their orientations (when they are known). We present complexity proofs and approximation algorithms for problems that include reversals and transpositions., Comment: PhD Dissertation, in Portuguese, presented at the Institute of Computing - Unicamp in March 2024

Linguistic ambiguity continues to represent a significant challenge for natural language processing (NLP) systems, notwithstanding the advancements in architectures such as Transformers and BERT. Inspired by the recent success of instructional models like ChatGPT and Gemini (In 2023, the artificial intelligence was called Bard.), this study aims to analyze and discuss linguistic ambiguity within these models, focusing on three types prevalent in Brazilian Portuguese: semantic, syntactic, and lexical ambiguity. We create a corpus comprising 120 sentences, both ambiguous and unambiguous, for classification, explanation, and disambiguation. The models capability to generate ambiguous sentences was also explored by soliciting sets of sentences for each type of ambiguity. The results underwent qualitative analysis, drawing on recognized linguistic references, and quantitative assessment based on the accuracy of the responses obtained. It was evidenced that even the most sophisticated models, such as ChatGPT and Gemini, exhibit errors and deficiencies in their responses, with explanations often providing inconsistent. Furthermore, the accuracy peaked at 49.58 percent, indicating the need for descriptive studies for supervised learning., Comment: in Portuguese language, 16 p\'aginas, 5 p\'aginas de ap\^endice e 4 imagens

Introduction and Objective. Assuming the need to rethink Education and its function as an element of social transformation and generator of a profound ethical change and promoter of other ways of being on planet Earth, this study seeks to understand the possible dialogues between Earth Pedagogy and Astrobiology in the construction and proposition of continuing education processes for science teachers. Methodology. A mini-course was promoted aimed at teachers and an attempt was made to report the construction process of the training process and, using Content Analysis, to analyze the contributions pointed out by the participants to their training and teaching practice. Results and Conclusion. The dialogue between knowledge in the continuing education of teachers contributes with fundamental elements to teaching practice, covering cognitive, emotional, individual and collective aspects, as well as highlighting the role of the university in promoting initiatives that bring Education and Complexity together., Comment: This article is written in Portuguese

In the research on FANETs (Flying Ad-Hoc Networks) and distributed coordination of UAVs (Unmanned Aerial Vehicles), also known as drones, there are many studies that validate their proposals through simulations. Simulations are important, but beyond them, there is also a need for real-world tests to validate the proposals and enhance results. However, field experiments involving drones and FANETs are not trivial, and this work aims to share experiences and results obtained during the construction of a testbed actively used in comparing simulations and field tests., Comment: in Portuguese language

We propose a physical mechanism for fine-tuning the phase of a domain wall around the equilibrium directions involving the application of an external field and a spin polarized current in opposite directions. In this way, the position of the domain wall remains unchanged, but its phase can be slightly modified around the initial equilibrium positions, applying the external field/current smoothly. We point out a few applications to which this fine tuning may lead., Comment: Written in portuguese. Submited to Revista Brasileira de Ensino de Fisica on March 15 2024

Blockchain technology has emerged as a necessity for the decentralization of payment methods and transactions, but it has brought with it many properties of distributed systems that have made it a crucial technology for overcoming some of society's challenges, especially in the context of decentralizing services, transparency of information, availability, and security. Its architecture and communication methods, although possessing some complex nuances to understand, particularly for the lay audience in the field of distributed systems, protocols, and computer networks. In this article, we will explore some topics of distributed systems related to blockchain technology., Comment: in Portuguese language

The growing interaction between traditional knowledge and formal sciences emerges as a relevant field of research. In this perspective, the aim of this article is to investigate the intersections between Physics and traditional knowledge in the ceramics practices of Vila Cuera, in Bragan\c{c}a, state of Para. Using an ethnographic approach, complemented by qualitative analysis, we realize that ceramists use their sensitive intuition and, masterfully, apply thermodynamic principles in the production of handmade ceramics. The results highlight the value of Ethnophysics, underlining that, long before the formal structuring of science as we know it, traditional societies already practiced and understood natural phenomena in tune with contemporary physical principles. We conclude that there is an inherent link between Physics and traditional knowledge with regard to the traditional ceramics practice, grounded on empirical observations and ancestral wisdom, that dialogues with science in a complementary relationship. The study highlights the importance of valuing and recognizing the knowledge of traditional populations by highlighting the knowledge doings of cultures and institutionalized science., Comment: in Portuguese

Since the development of lasers, we have continuously sought to advance techniques and theory to obtain beams with a high degree of coherence, as natural light sources provide incoherent light. However, there are applications where it is advantageous to use partially coherent (PC) beams in a controlled manner, such as in propagation through turbulent media. To generate a PC beam in the laboratory or in simulations, specific theories and methods are required. In this article, we provide an introduction to PC beam theory, describing how to generate them through modal decompositions and a step-by-step guide for simulating and analyzing beam generation inspired by experiments. To illustrate the methods, we present Gaussian Schell-Model beams as an example., Comment: 12 pages, in Portuguese language, 11 figures

In this study, we will address some topics related to the privatization of airports in the scientific literature, in an attempt to provide an answer to the following question: does the privatization of airports bring positive results? Firstly, we turn our attention to the motivations leading to privatization, considering the two main parties involved, the government and the private sector. After all, the success of such a decision will be relative to the reasons that justify it. In a second moment, we will consider the regulatory issue, whose influence on the airport's financial performance is consolidated in the literature. In the third part, we address the main documented results of privatization, with special attention to productive efficiency, whose improvement is the most popular motivation for privatization., Comment: This article is written in Portuguese

This work focuses on trying to understand how the construction of an airline's network is made. For this purpose, the case of Azul was studied, investigating which and how factors affect the decision of this airline to enter domestic routes, in addition to analyzing how the merger of Azul with the regional airline Trip affected the company's network planning. For this, an academic study was conducted using an econometric model to understand the airline's entry model. The results show that Azul's business model is based on connecting new destinations, not yet served by its competitors, to one of its hubs, and consistently avoiding routes or airports dominated by other airlines. Regarding the effects of the merger, the results suggest that Azul moved away from its original entry model, based on JetBlue, to a model more oriented towards regional aviation, entering shorter routes and regional airports., Comment: This article is written in Portuguese

In recent years, the topic of global warming and greenhouse gas emissions has been increasingly in the media. This theme has raised various flags, showing concern for the future and seeking alternatives for a more sustainable life over the years. When studying greenhouse gas emissions, one of the main emitters of such gases is the burning of fuels, in which transport vehicles that depend on gas and oil are included. In this respect, air transport through aircraft is one of the sources emitting such gases. Aiming to reduce gas emissions, one of the ways to do this is by reducing fuel consumption; for this, aircraft would have to be more efficient, or the offer and demand for flights would be reduced. However, what if aircraft fuel consumption were taxed? What would be the effects of this on air transport? Could this be one of the alternatives to reduce emissions? To understand this relationship between taxation and a possible reduction in fuel consumption, a study was developed by the Aeronautics Institute of Technology (ITA), using an econometric model to understand how demand would be affected by changes in airfares. In addition, a simulation of possible environmental taxes on the values of air tickets was carried out to analyze the demand response and to get an idea if this taxation would really solve the emission problems., Comment: This article is written in Portuguese

The exploration of existing commercial opportunities has been increasing the share of commercial (non-aeronautical) revenues in the total revenues of airports worldwide. These revenues, also called commercial, non-aeronautical, or non-tariff revenues, come from rentals, duty-free shops, food and beverage sales, parking, advertising, etc. In other words, everything that is not the main business of the airport. Consequently, the dependence on commercial revenues has also become increasingly important, and airport managers are interested in understanding how to improve their financial results with this new revenue source, as it not only improves financial outcomes but also optimizes passengers' time and money consumption options at airports. Therefore, this chapter seeks to discuss the main determinants of commercial revenues at national airports, analyzing the possible impacts of the behavior of passengers from low-cost carriers (LCC) on these revenues, combined with other determining factors., Comment: This article is written in Portuguese

This study addresses the growing standardization of airline fleets, highlighting that frequent passengers are more likely to fly on the same aircraft model more often. The objective is to analyze the fleet management of airlines and the impact of a reduced variety of models on company operations. The benefits of standardization, such as operational efficiency, and the risks, such as vulnerability to specific model failures, are discussed. The work reviews international scientific literature on the subject, identifying consensus and disagreements that suggest areas for future research. It also includes a study on the Brazilian market, examining how standardization affects operational costs and profitability in terms of model, family, and aircraft manufacturer. Furthermore, the relationship between fleet standardization and the business model of the companies is investigated, concluding that the advantages of standardization are not exclusive to low-cost companies but can also be leveraged by other airlines., Comment: This article is written in Portuguese

This study explores the approaches used by airlines in setting flight times. It highlights the need to balance operational and strategic factors, such as optimizing the use of resources - including aircraft, crew, and fuel - and managing the risks related to delays and congestion. The work details a national analysis focused on domestic flights, investigating the factors that influence companies to adjust scheduled flight times and the impact of this practice on punctuality. The results indicate that decisions about flight time are influenced by both operational and strategic aspects, being affected by competition and the sector's policies on punctuality and slot allocation. Furthermore, it was found that adding extra time is an effective strategy for reducing delays, although it may conceal system deficiencies., Comment: This article is written in Portuguese

This work presents an analysis of recent literature examining factors that influence flight times in Brazil, with special attention to the impact of new technology implementations, specifically Performance-Based Navigation (PBN). PBN procedures began to be implemented in Brazilian airspace in 2009 and represent a new concept of air navigation, using satellites to create 3D flight routes that are shorter and more precise, potentially reducing the distances flown and consequently flight times and delays. Flight times depend on various factors, such as the size and complexity of the origin and destination airports, weather conditions, aircraft models, and how full the flights are. Therefore, to assess the impact of the new procedures, the variation in this set of factors must be taken into account. The results found in the literature suggest that Performance-Based Navigation had a positive impact, reducing flight times by about 1-2%, representing a saving of tens of thousands of flight hours from the beginning of implementations in 2009 until the end of 2018., Comment: This article is written in Portuguese

Flight delays are a reality in the modern air industry worldwide. However, studies in the literature have investigated the competitive determinants of delays arising from factors originating at the airport and along the route separately. This work aims to present a national study that used a unifying approach from the literature, considering the local and global effects of competition on delays. The analysis took into account a phenomenon known as the "internalization of externalities" of airport congestion. Furthermore, it discusses the relationship between quality and competition on the route and the impacts of the entry of a low-cost carrier (LCC) on the delays of incumbent airlines in the Brazilian air market. The literature suggests that there is evidence of congestion internalization at Brazilian airports, in parallel with competition for quality at the route level. Additionally, the potential competition caused by the presence of the LCC leads to a global effect that suggests the existence of impacts other than prices on routes where it has not entered., Comment: This article is written in Portuguese

This study discusses the literature on the convergence of business models of airlines in Brazilian air transport, focusing on the formation of flight networks. Initially, it analyzes the determinants of the network formation patterns of the "fundamental" business models (archetypes) of airlines in the first years after the sector's deregulation. Then, it discusses how the business models of Brazilian companies resemble these patterns. The literature highlights convergences between the network formation strategies of full-service companies in relation to older low-cost companies, in addition to business model redirections after mergers and acquisitions., Comment: This article is written in Portuguese

This book, written in Portuguese, presents a comprehensive analysis of the air transport industry in Brazil, highlighting its vital importance to the country's economy. It explores the sector's complexity, from economic characteristics to interaction with the national aeronautical industry, through the specialization of the workforce and market demand analysis. The book delves into the economic regulation of air transport, tracing the evolution from periods of strict regulation to phases of liberalization and deregulation, and examines market dynamics, focusing on concentration and competitiveness. It also analyzes demand and supply through case studies, investigating everything from tourists traveling within Brazil to the coverage of the national territory and the prices of air tickets. Finally, the book proposes principles for the regulation and public policies of the air sector, emphasizing the priority of the passenger, the business environment, access to air transport, and economic efficiency, culminating in the advocacy for a free market, but with protection for competition and the consumer., Comment: Pezco Editora & Desenvolvimento - 1st Edition, 2009. In Portuguese

The intention of this article is to propose the use of artificial intelligence to detect through analysis by UFO ontology the emergence of verbal and physical aggression related to psychosocial deficiencies and their provoking agents, in an attempt to prevent catastrophic consequences within school environments., Comment: in Portuguese language. Minha vez de falar sobre a realidade

This systematic review focuses on analyzing the use of machine learning techniques for identifying and quantifying analytes in various electrochemical applications, presenting the available applications in the literature. Machine learning is a tool that can facilitate the analysis and enhance the understanding of processes involving various analytes. In electrochemical biosensors, it increases the precision of medical diagnostics, improving the identification of biomarkers and pathogens with high reliability. It can be effectively used for the classification of complex chemical products; in environmental monitoring, using low-cost sensors; in portable devices and wearable systems; among others. Currently, the analysis of some analytes is still performed manually, requiring the expertise of a specialist in the field and thus hindering the generalization of results. In light of the advancements in artificial intelligence today, this work proposes to carry out a systematic review of the literature on the applications of artificial intelligence techniques. A set of articles has been identified that address electrochemical problems using machine learning techniques, more specifically, supervised learning., Comment: in Portuguese language

Mental health is an essential component for students' overall development and for creating a healthy and productive school environment. This paper reviews the literature on mental health in schools, highlighting the importance of psychopedagogical interventions. Key risk and protective factors are discussed, along with intervention strategies that can be implemented in the school context. It is concluded that an integrated approach, involving collaboration among educators, psychopedagogues, families, and the community, is fundamental for promoting mental health and academic success for students.