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The purpose of this paper is to evaluate the fatigue process through the dynamic analysis of the global structural model and local static sub-modelling in a critical detail using the hot-spot stress approach. The detail was studied in three different positions at the “Alcácer do Sal” access viaduct, and the methodologies from the IIW and Eurocode EN 1993-1-9 were compared.

In this study, the fatigue life process based on the hot-spot stress approach was evaluated using a global dynamic analysis and a local sub-modelling based on a static analysis of welded connections in the “Alcácer do Sal” railway structure, Portugal, taking into consideration the recommendations from IIW and Eurocode EN 1993-1-9. The hot-spot stresses were calculated through the static analysis of the sub-model of the welded connection for each vibration mode with the aim to obtain the temporal stresses using the modal coordinates and modal stresses of the extrapolation points. The Ansys® and Matlab® softwares were used for the numerical analysis and the hot-spot stress calculations, respectively.

The proposed methodology/approach to obtain fatigue assessment is based on the modal analysis of the global structural model and local static sub-modelling. The modal analysis was used to extract the boundary conditions to be used in the local model to determine the temporal stresses of the extrapolation points. Based on the modal superposition method, the stresses as function of time were obtained for fatigue life evaluation of a critical detail by the hot-spot stress approach. The detail was studied in three different positions.

In the present study, a global-local fatigue methodology based on dynamic analysis of the global structural model and local static sub-modelling of the critical detail using the hot-spot stress approach is proposed. Herein, the modal analysis of the global structural model supported by the modal superposition method was used to obtain the matrix of modal coordinates. The static analysis of the local sub-model for each mode from the modal analysis of global structural model was done to estimate the hot-spot stresses. The fatigue damage calculation was based on S-N curve of the critical detail and rainflow method. The IIW recommendation proved to be more conservative compared to the proposed rules in the Eurocode EN 1993-1-9. The global-local modelling based on dynamic analysis is an important and effective tool for fatigue evaluation in welded joints.

Tourism in South America has been largely overlooked compared to other tourism developing regions such as Asia and Africa. Decades of political and economic uncertainty have directly influenced tourism development in the region and explain tourism’s current state. Despite its dimension, diversity and attractiveness, Brazil has only recently recognized the tourism industry as a promoter of economic and social development. Recent trends in the tourism industry in Brazil clearly illustrate the correlation between economic and political stability and development in tourism. This paper discusses the major issues that have influenced and shaped tourism in Brazil and addresses the major developments in the last decade and the future perspectives for the industry.

This study aims to evaluate in situ oxidative polymerization of aniline (Ani) as a post-processing method to promote extrusion-based 3D printed parts, made from insulating polymers, to components with functional properties, including electrical conductivity and chemical sensitivity.

Extrusion-based 3D printed parts of polyethylene terephthalate modified with glycol (PETG) and polypropylene (PP) were coated in an aqueous acid solution via in situ oxidative polymerization of Ani. First, the feedstocks were characterized. Densely printed samples were then used to assess the adhesion of polyaniline (PAni) and electrical conductivity on printed parts. The best feedstock candidate for PAni coating was selected for further analysis. Last, a Taguchi methodology was used to evaluate the influence of printing parameters on the coating of porous samples. Analysis of variance and Tukey post hoc test were used to identify the best levels for each parameter.

Colorimetry measurements showed significant color shifts in PP samples and no shifts in PETG samples upon pullout testing. The incorporation of PAni content and electrical conductivity were, respectively, 41% and 571% higher for PETG in comparison to PP. Upon coating, the surface energy of both materials decreased. Additionally, the dynamic mechanical analysis test showed minimal influence of PAni over the dynamic mechanical properties of PETG. The parametric study indicated that only layer thickness and infill pattern had a significant influence on PAni incorporation and electrical conductivity of coated porous samples.

Current literature reports difficulties in incorporating PAni without affecting dimensional precision and feedstock stability. In situ, oxidative polymerization of Ani could overcome these limitations. However, its use as a functional post-processing of extrusion-based printed parts is a novelty.

The purpose of this paper is to characterize real estate lease management of the São Paulo City Municipality (PMSP), the largest metropolitan region in Latin America, for the provision of public education, health and social assistance services.

In addition, the management was also evaluated by a direct analysis of the obtained data (lease paid, area of the property, agency, zone, region, neighborhood, contract date, etc.) and by statistical regressions.

The results showed that the following: real estate properties with the greatest discrepancy of amounts paid (when compared to other amounts paid by the city and the market) are in a pulverized category, called “Others”; PMSP faces difficulties tracking expiration dates, 18.9% of the assets are still in use, though present expired contracts; the category “Education” is the most expressive in expenses; there is a limit to the correlation between the size of the real estate and the lease price paid, and very large real estate do not have proportionally higher leases; the location only directly affects the lease value if it is in the central region of the Metropolis. There is no explicit relationship for leases in other regions.

This work is groundbreaking for helping to consolidate the literature on real estate management in developing countries. Factors that integrate and influence the management of real estate leases for government agencies in a Latin American metropolitan area have never before been reported in the literature.

The authors investigated the effect of basic human values in the prediction of COVID-19 vaccination behavior amongst public security agents in Brazil.

A sample of 15,313 Brazilian public security agents responded to the portrait values questionnaire and a COVID vaccination behavior measure. Multidimensional scaling analysis (MDS) was used to observe the order of the predicted by the theory. For hypotheses, the authors ran a series of Structural equation modeling (SEM) with direct effects between values and vaccination rate.

Results suggest that the values of conservation and self-transcendence positively predicted vaccination. A nonsignificative negative prediction was obtained for openness to change and self-enhancement values on vaccination behavior.

Data were collected using self-report questionnaires.

Institutional management should encourage capacitation campaigns aimed at public security agents, enabling a significant increase in vaccine protection for the public security institutions.

The reinforcement of conservation and self-transcendence values lead to the perception of the vaccine as a measure of caring for people in general and for the members of the ingroup, hence motivating the vaccination behavior.

The findings confirm that values encourage individuals to be vaccinated, due to their intrinsic motivation. This relationship did not appear to be clearly tested by previous empirical studies.

The purpose of this study is to investigate the influence of firm-specific investor sentiment on Brazilian companies’ accrual-based earnings management between 2010 and 2018. The paper aims to bring deeper insight into the relationship between the investor expectations and managers’ decision-making in an emerging market.

The authors use the quantitative approach and apply a multiple linear regression model to test the relationship among the abnormal accruals, the firm-specific investor sentiment index and the control variables. The final sample includes data from 175 companies, between 2010 and 2018.

These results reveal a negative association between firm-specific investor sentiment and accrual-based earnings management, which could mean that the risk propensity of managers to manipulate earnings increases when they face known losses in the capital market.

The research findings provide a valuable understanding of how emerging capital market expectations can influence managerial decisions, such as accrual-based earnings management. The geographical area of study was limited to only Brazil.

Previous studies on developed markets show that market-wide investor sentiment positively influences accrual-based earnings management. However, the present study shows that the firm-specific investor sentiment index has a significant and negative relationship with Brazilian companies’ earnings manipulation, whereas market sentiment indicates contradictory relationship in previous studies in the country.

El propósito de este estudio es investigar la influencia del sentimiento de los inversionistas a nivel de empresa en la manipulación contable de las empresas brasileñas entre 2010 y 2018. El documento pretende aportar una visión más profunda sobre la relación entre las expectativas de los inversores y la toma de decisiones de los gestores en un mercado emergente.

usamos el enfoque cuantitativo y aplicamos un modelo de regresión lineal múltiple para probar la relación entre las acumulaciones anormales, el índice de sentimiento de los inversores a nivel de empresa y las variables de control. La muestra final incluye datos de 175 empresas, entre 2010 y 2018.

Los resultados revelan una asociación negativa entre el sentimiento de los inversores a nivel de empresa y la manipulación contable basada em acumulaciones, lo que podría significar que la propensión al riesgo de los administradores a manipular las ganancias aumenta cuando enfrentan pérdidas conocidas en el mercado de capitales.

los resultados de la investigación proporcionan una valiosa comprensión de cómo las expectativas de los mercados de capitales emergentes pueden influir en las decisiones de gestión, como la manipulación contable basada en acumulaciones. El área geográfica de estudio se limitó únicamente a Brasil y, en consecuencia, los hallazgos y conclusiones del estudio tuvieron sus límites.

estudios anteriores sobre mercados desarrollados muestran que el sentimiento de los inversores a nivel de mercado influye positivamente en la manipulación contable. Sin embargo, el presente estudio muestra que el índice de sentimiento de los inversores a nivel de empresa tiene una relación significativa y negativa con la manipulación de las ganancias de las empresas brasileñas, mientras que el sentimiento del mercado indica una relación contradictoria en estudios anteriores en el país.

investigate and analyze the aspects of legitimation, theorization and trends for the evolution of research in information technology governance (ITG) in Brazil, according to researchers familiar with the matter.

By means of a qualitative and quantitative research of exploratory-descriptive approach, the Delphi method was applied using a questionnaire supported by content analysis.

ITG is an increasingly interdisciplinary research field, with significant help from other fields of knowledge, such as administration, computer science and engineering. The main means of ITG publication are periodicals (MISQ, JMIS, JISTEM RESI), scientific events (AMCIS, ECIS, HICSS, EnANPAD, CONTECSI) and researchers, such as Peter Weill and Edimara Mezzomo Luciano. Best practice models are the most significant theoretical frameworks, and the main trend of research are on emerging technologies such as cloud computing and Internet of things (IoT) in the context of ITG.

To the unavailability of some researchers to participate in the second phase of the Delphi research performed, as well as the non-completion of a third Delphi round. Likewise, the “Block B (open answer questions)” it was not contemplated in the second phase for a new collection of answers, which could partially change the results presented here.

The results show important insights for ITG researchers that can allow new researches about its applications, jointly reflecting on relevant aspects for the advancement of this research field.

There are several research contributions to broaden the discussion and the evolution of this new scientific field in Brazil and that can be grouped for each set of stakeholders: academia and related researchers; the practicing community of business managers and private and public organizations; the academic legitimizing bodies; the non-academic legitimating bodies and researchers from other areas of knowledge.

ITG is a concept that emerged as part of corporate governance (CG), which has evolved as an emerging theme and is expanding in the international academic arena. However, the current stage of legitimation, theorization and trends of ITG in the Brazilian researches are lacked greater understanding, in order to provide better targeting for new researches.

This paper aims to address the development and implementation of “AltPrint,” a slicing algorithm based on a new filling process planning from a variation in the deposited material geometry. AltPrint enables changes in the extruded material flow toward local variations in stiffness. The technical feasibility evaluation was conducted experimentally by fused filament fabrication (FFF) process of snap-fit subjected to a mechanical cyclical test.

The methodology is based on the estimation of the parameter E from the mathematical relationships among the variation of the material in the material flow, nozzle geometry and extrusion parameters. Calibration, validation and analysis of the printed specimens were divided into two moments, of which the first refers to the material responses (flexural and dynamic mechanical analysis) and the second involves the analysis of the printed components with localized flow properties (for estimating the response to cyclic loading). Finite element analysis assisted in the comparison of two snap-fit geometries, one traditional and one generated by AltPrint. Finally, three examples of compliant mechanisms were developed to demonstrate the potential of the algorithm in the generation of functional prototypes.

The contribution of AltPrint is the variable fill width integrated with the slicing software that varies the print parameters in different regions of the object. The alternative extrusion method based on material rate variation was conceived as an “open software” available in GitHub platform, hence, open manufacturing with initial focus on desktop 3D printer based on FFF. The slicing method provides deposited variable-width segments in an organized and replicable filling strategy, resulting in mechanical properties variations in specific regions of a part. It was implemented and evaluated experimentally and indicated potential applications in parts manufactured by the additive process based on extrusion, which requires local flexibilities.

This paper presents a new alternative method for application in an open additive manufacturing context, specifically for additive extrusion techniques that enable local variations in the material flow. Its potential for manufacturing functional parts, which require flexibility due to cyclic loading, was demonstrated by fabrication and experimental evaluations of parts made in acrylonitrile butadiene styrene filament. The changes proposed by AltPrint enable geometric modifications in the response of the printed parts. The proposed slicing and filling control of parameters is inserted in a context of design for additive manufacturing and shows great potential in the area of product design.

The purpose of this study is to investigate the influence of light intensity and sources of carbon and nitrogen on the cultivation of Spirulina maxima.

Cultures were carried out in a modified Zarrouk medium using urea, sodium acetate and glycerol. A Taguchi experimental design was used to evaluate the effect on the production of biocompounds: productivities in biomass, carbohydrates, phycocyanin and biochar were analyzed.

Statistical data analysis revealed that light intensity and sodium acetate concentration were the most important factors, being significant in three of the four response variables studied. The highest productivities in biomass (46.94 mg.L⁻¹.d⁻¹), carbohydrates (6.11 mg.L⁻¹.d⁻¹), phycocyanin (3.62 mg.L⁻¹.d⁻¹) and biochar (22, 48 mg.L⁻¹.d⁻¹) were achieved in experiment 4 of the Taguchi matrix, highlighting as the ideal condition for the production of biomass, carbohydrates and phycocyanin.

Sodium acetate and urea can be considered, respectively, as potential sources of carbon and nitrogen to increase Spirulina maxima productivity. From the results, an optimized cultivation condition for the sustainable production of bioproducts was obtained.

This work focuses on the study of the influence of light intensity and the use of alternative sources of nitrogen and carbon on the growth of Spirulina maxima, as well as on the influence on the productivity of biomass and biocompounds. There are few studies in the literature focused on the phycocyanin production from microalgae, justifying the need to deepen the subject.