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This work aims to provide additional insights regarding the practicability of using conventional materials in the fused filament fabrication (FFF) process.

Two different acrylonitryle butadiene styrene (ABS) grades are studied and compared, aiming to check to what extent the regular ABS developed for conventional polymer processing, with a different rheology than the one provided for the FFF process, can also be used in this process (FFF).

The rheological results show that a general-purpose ABS (ABS-GP) melt is much more viscous and elastic than ABS-FFF. It is clear that using ABS-GP as feedstock material in the FFF process results in poor coalescence and adhesion between the extruded filaments, which has a detrimental effect on the mechanical properties of the printed specimens. Despite its lower performance, ABS-GP can be a good choice if the objective is to produce an aesthetical prototype. If the objective is to produce a functional prototype or a final part, its mechanical performance requirements will dictate the choice.

This work provides insightful information regarding the use of high viscosity materials on the 3D printing process.

The purpose of this paper is to develop new boundary conditions for simulating the injection molding process of polymer melts.

The boundary conditions are derived and implemented to simulate real-life air vents (used to allow the air escape from the mold). The simulations are performed in the computational library OpenFOAM® by considering two different fluid models, namely, Newtonian and generalized Newtonian (Bird–Carreau model).

A detailed study on the accuracy of the solver interFoam for simulating the filling stage is presented, by considering simple geometries and adaptive mesh refinement. The verified code is then used to study the three-dimensional filling of a more complex geometry.

The results obtained showed that the numerical method is stable and allows one to model the filling process, simulating the real injection molding process.

This paper aims to investigate the existing relations between the management of public bonds on the dynamics of debt, term structure of interest rates and economic cycle, through a dynamic stochastic general equilibrium model (DSGE), which was estimated through Bayesian inference techniques using data from Brazil.

The model developed was used to investigate the effects of the public debt average maturity management when the economy faces a monetary policy shock. For this, three management scenarios are evaluated, including Brazilian securities average term.

Contrary to what might be inferred from DSGE models that limited the analysis of the debt term by imposing only one-period bonds, a contractionary monetary policy shock does not necessarily cause public debt to increase significantly. Debt term structure plays a crucial role in this result since the government does not need to roll the debt over at higher costs when the debt term profile is longer, reducing the debt service costs and then the impact on the overall debt.

Despite the relevance of this theme and its implications for the dynamics of the economy, there is still a gap to be filled in the literature when using DSGE models, since most part of the work that used this methodology limited the analysis of the debt term by imposing that government issues only one-period bonds. This paper differs from the others insofar as it promotes an investigation focused on the role played by debt maturity management on the performance of the contractionary monetary policy. This approach can generate a better understanding of debt management policy and its interaction with fiscal and monetary policies.

This paper aims to reflect on retirement, showing its different viewpoints, advocating the need to understand the issue from a procedural and multidimensional perspective, and especially, defending a more active role of human resource management in the process.

This paper presents a theoretical framework of retirement, based on a procedural and multidimensional perspective.

To study how individuals adapt to retirement permits the discovery, for example, of how they obtain the quality of life after the transition and how they manage the internal and external aspects of the process. Human resource management must treat retirement as a complex and multidimensional phenomenon. This means it should consider retirement not only as a decision but also as a process.

This essay seeks to reflect on retirement, advocating the need to understand the issue from a procedural and multidimensional perspective, and especially, defending a more active role of human resource management in the process.

The aim of this study was to determine if there are asymmetries in the pass-through of West Texas Intermediate (WTI) crude oil prices to its derivatives (diesel and gasoline) in the Brazilian market.

Initially, the future WTI oil price series was analyzed using the self-exciting threshold autoregressive (SETAR) and logistic smooth transition autoregressive (LSTAR) non-linear models. Subsequently, the threshold autoregressive error-correction model (TAR-ECM) and Markov-switching model were used.

The findings indicated high prices throughout 2008 due to the subprime crisis. The findings indicated high prices throughout 2008 due to the subprime crisis. The results indicated that there is long-term pass-through of oil prices in both methods, suggesting an equilibrium adjustment in the prices of diesel and gasoline in the analyzed period. Regarding the short term, the variations in contemporary crude oil prices have positive effects on the variations in fuel prices. Lastly, this behavior can partly be explained by the internal price management structure adopted during almost all of the analyzed period.

This paper contributes to the literature at some points. The first contribution is the modeling of the oil price series through non-linear models, further enriching the literature on the recent behavior of this time series. The second is the simultaneous use of the TAR-ECM and Markov-switching model to capture possible short- and long-term asymmetries in the pass-through of prices, as few studies have applied these methods to the future price of oil. The third and main contribution is the investigation of whether there are asymmetries in the transfer of oil prices to the price of derivatives in Brazil. So far, no work has investigated this issue, which is very relevant to the country.

This paper aims to analyze the macroeconomic effects of a monetary policy shock considering that fiscal policy is under fiscal constraints. For that, a dynamic stochastic general equilibrium (DSGE) model was developed for Brazil, which was estimated through Bayesian econometrics.

In the basic model, the government does not have any type of fiscal restriction. The other two estimated models, however, consider that the fiscal authority implements some kind of fiscal rule. One of these rules is the Constitutional Amendment 95/2016 (EA 95/2016), which includes a limitation for government spending. The other Alternative Rule seeks to represent the characteristics of a more austere fiscal rule, as proposed by Wesselbaum (2017).

It was possible to verify in this paper that the implementation of EA 95/2016 by the Brazilian government does not produce statistically different results and that it reduces the welfare of the households in relation to the scenario without fiscal rule. Thus, the proportionate benefit of EA 95/2016 is less than the cost associated with this fiscal rule (less welfare). If the government adopts a fiscal constraint similar to the Alternative Rule, it is possible to considerably reduce the interaction between fiscal and monetary policy, thereby reducing the fiscal dominance policy over monetary policy. However, the cost in terms of welfare is much higher than the baseline scenario. Thus, the fiscal authority is subject to a trade-off among public debt stabilization and household welfare.

The study intends to contribute to the literature on three specific points. First, the monetary–fiscal policy interaction within a representative model of the Brazilian economy is discussed. In addition, the study considers that the government can adopt EA 95/2016 and the Alternative Rule, used in the US economy. Second, the impacts of EA 95/2016 and the Alternative Rule on household welfare will be quantified. Finally, two types of individuals (Ricardian and non-Ricardian agents) and two sectors of production (wholesalers and retailers) are considered. In this paper, the DSGE model is estimated, since the previously mentioned authors performed simulations

Housing prices in Brazil have displayed an impressive growth in recent years, raising some concerns about the existence of a bubble in housing markets. In this paper, the authors implement an empirical methodology to identify whether or not there is a bubble in housing markets in Brazil.

Based on a theoretical model that establish that, in the absence of a bubble, a long-run equilibrium relationship should be observed between the market price of an asset and its dividends. The authors implement two methodologies. First, the authors assess whether there is a cointegration relationship between housing prices and housing rental prices. Second, the authors test whether the price-to-rent ratio is stationary.

The authors’ results show that there is evidence of a bubble in housing prices in Brazil. However, given the short span of the data, the authors perform a Monte Carlo simulation and show that the cointegration tests may be biased in small samples. Therefore, the authors should be caution when assessing the results.

The results obtained from the cointegration analysis can be biased for small samples.

The information on the excessive increase of the prices of the properties in relation to their fundamental value can help in the decision-making on investment of the economic agents.

These results corroborate the hypothesis that Brazil has an excessive appreciation in housing prices, and, as Silva and Besarria (2018) have suggested, this behavior explains, in part, the fact that the central bank has taken this issue into account when deciding about the stance of monetary policy of Brazil.

The originality is linked to the use of the Gregory-Hansen method of cointegration in the identification of bubbles and discussion of the limitations of the research through Monte Carlo simulation.

The purpose of this paper is to investigate the effects of income inequality on the economic growth of Brazilian states in the period from 1994 to 2014. The transmission mechanism of the effects of income inequality on economic growth is derived from the model proposed by Halter et al. (2014).

The empirical formulation adopted to achieve this goal is divided into two stages. The first stage is limited to short-term analysis, and panel data models with fixed effects, random effects, and instrumental variables are used. In the second stage, the discussion turns to the use of the error correction model for a cointegrated panel.

The findings of this study suggest that inequalities in income and educational level are the principal determinants of different growth rates among Brazilian states. More specifically, it is found that additional years of schooling positively influence growth. By contrast, income inequality negatively affects this indicator.

The present study differs from the others in that it adapts the discussion proposed by Halter et al. (2014) to the analysis of Brazilian states. Halter et al. (2014) derive the transmission channel between income inequality and economic growth, showing a non-monotonic adjustment trajectory of production that leads to a linear theoretical model of income inequality and economic growth that is similar to those used in this type of approach.

The purpose of this paper is to evaluate the chemical and functional composition of acerola, guava and cashew freeze-dried pomaces.

Fruit pomaces were obtained from the pulp juice industrial sector and submitted to freeze-drying. Samples were analysed for composition (macronutrients, micronutrients, moisture and ash), technological attributes (morphological, hygroscopicity, retention of oil and water and solubility), bioactive compounds (total phenolics, flavonoids, proanthocyanins, anthocyanins, carotenoids and ascorbic acid), antioxidant and antimicrobial properties. Total phenolics, brown pigments and antioxidant activity of thermally treated samples were evaluated. Results were presented as mean and standard deviation, and submitted to Shapiro–Wilk normality test, and ANOVA statistical significance follows by Tukey’s post hoc test (p<0.05). Also, Pearson correlation coefficients were used to test the relationship between selected parameters.

Guava pomace had the highest insoluble fibre (40.6 per cent), protein (13.8 per cent) and lipid (9.3 per cent) contents and acerola higher soluble fibre (14.2 per cent) and water and oil holding capacity (12 and 5.4 g/g, respectively). Cashew pomace had higher solubility (45.3 per cent) and hygroscopicity (11.2 per cent). Acerola pomace had the highest phenolic content (5,331.7 mg AGE/100 g), DPPH and oxygen radical absorbance capacity antioxidant activity (63.3 and 756.6 µmol TE/g). Despite of that none of extracts showed antibacterial activity. All pomaces presented good antioxidant activity retention after thermal treatments (> 70 per cent), which might be correlated to thermally induced brown pigments.

This investigation was motivated by the large amounts of pomaces produced by the fruit pulp and juice processing industries, which represents a waste of residual phytochemicals and cause potential environmental problems. Overall, it was demonstrated that freeze-dried acerola, guava and cashew pomaces are promising ingredients for multiple food applications.

The purpose of this research was to develop new sustainability indicators consistent with the sand mould casting industry, through benchmarking of cleaner production (CP), in order to identify the levels of practice and performance of companies of the casting sector. In addition, a lean manufacturing checklist was specified in order to verify the presence of lean manufacturing techniques employed to eliminate waste towards CP. No previous work was found in the literature that attempts to assess practices and performance of companies performing sand mould casting (a significantly polluting manufacturing process) in the context of CP and lean manufacturing.

For the application of this benchmarking, nine companies from the sand mould casting sector were studied, where the profile of each company was analysed through eight variables and 47 indicators. Data was obtained through face-to-face visits and questionnaire application in the companies, and the data was analysed both quantitatively and qualitatively.

The results obtained were the diagnosis of companies' practices and performance resulting from their position in the benchmarking charts, as well as the identification of the areas in which companies should implement improvements aiming at achieving CP.

This research was developed specifically for sand mould casting companies, and each process has its own characteristics

14 companies were invited to participate in this survey, but nine companies agreed to participate. Unfortunately, there were companies that declined to participate in the survey.

It is important to diagnose casting companies regarding CP practices, performance and deployment potential. Thus, important negative issues in the company can be identified, and with this information, they can develop actions focussed on cases that need more attention. In addition, this work contributes to evaluate the relationship and efficiency of improvement actions developed by companies in the context of both lean manufacturing and CP, aiming to reduce or eliminate the environmental impact. The improvement of practices and performance of a company regarding CP is considered to be beneficial to supply chain management in the context of sustainability, as the other participating companies are likely to seek ways to reduce environmental impact, and the diagnostics provided by this work may also be used by those companies.