Paulo Reis, Mariana Volpini, Joana Pimenta Maia, Igor Batista Guimarães, Cristiane Evelise, Maurício Monteiro and Juan Carlos Campos Rubio
The purpose of this study is to validate a novel model of resting hand splint manufactured by additive manufacturing (AM) and compare it with the traditional model manufactured by…
Abstract
Purpose
The purpose of this study is to validate a novel model of resting hand splint manufactured by additive manufacturing (AM) and compare it with the traditional model manufactured by high temperature thermoplastic in terms of cost, weight, volume and thermal comfort.
Design/methodology/approach
A novel resting hand splint model was created from the topology optimization (TO) and analyzed, by finite-element analysis, manufacturing cost and weight, with a traditional resting hand splint. A pilot clinical study was carried out to verify heat diffusion during the use of the two splints.
Findings
The results showed that compared with the traditional model, the novel model reduced the volume of material used by 35.48%, the weight of the orthosis by 17.56% and the maximum surface deformation by 171.17% when subjected to actuation forces. It was also verified that, when manufactured with Nylon by AM, the new model is 1.5 times cheaper than the traditional model made of Polypropylene. The result of the thermographic analysis showed greater temperature variation in the use of the traditional splint (+4.6°C) compared to the temperature variation observed in the nylon splint (2.1°C).
Practical implications
These results have as clinical relevance the demonstration of the feasibility of manufacturing functional orthoses that are more comfortable, cheaper and lighter than traditional ones.
Originality/value
This study describes the use of TO to manufacture a novel resting hand splint, which was compared with the commonly used traditional splint in terms of mechanical resistance, weight, cost and thermal comfort.
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Flávio Alexandre Matias Arrais, Nuno Lopes and Paulo Vila Real
Stainless steel has different advantages when compared to conventional carbon steel. The corrosion resistance and aesthetic appearance are the most known; however, its better…
Abstract
Purpose
Stainless steel has different advantages when compared to conventional carbon steel. The corrosion resistance and aesthetic appearance are the most known; however, its better behaviour under elevated temperatures can also be important in buildings design. In spite of the initial cost, stainless-steel application as a structural material has been increasing. Elliptical hollow sections integrate the architectural attributes of the circular hollow sections and the structural advantages of the rectangular hollow sections (RHSs). Hence, the application of stainless-steel material combined with elliptical hollow profiles stands as an interesting design option. The purpose of the paper is to better understand the resistance of stainless-steel-beam columns in case of fire
Design/methodology/approach
The research presents a numerical study on the behaviour of stainless-steel members with slender elliptical hollow section (EHS) subjected to axial compression and bending about the strong axis at elevated temperatures. A parametric numerical study is presented here considering with and without out-of-plane buckling different stainless-steel grades, cross-section and member slenderness, bending moment diagrams and elevated temperatures.
Findings
The tested design methodologies proved to be inadequate for the EHS members being in some situations too conservative.
Originality/value
The safety and accuracy of Eurocode 3 (EC3) design methodology and of a recent design proposal developed for I-sections and cold-formed RHSs are analysed applying material and geometric non-linear analysis considering imperfections with the finite element software SAFIR.
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Flávio Arrais, Nuno Lopes and Paulo Vila Real
Sigma cross-section profiles are often chosen for their lightness and ability to support large spans, offering a favourable bending resistance. However, they are more susceptible…
Abstract
Purpose
Sigma cross-section profiles are often chosen for their lightness and ability to support large spans, offering a favourable bending resistance. However, they are more susceptible to local, distortional and lateral-torsional buckling, as possible failure modes when compared to common I-sections and hollow cross-sections. However, the instability phenomena associated to these members are not completely understood in fire situation. Therefore, the purpose of this study is to analyse the behaviour of beams composed of cold-formed sigma sections at elevated temperatures.
Design/methodology/approach
This study presents a numerical analysis, using advanced methods by applying the finite element software SAFIR. A numerical analysis of the behaviour of simply supported cold-formed sigma beams in the case of fire is presented considering different cross-section slenderness values, elevated temperatures, steel grades and bending moment diagrams. Comparisons are made between the obtained numerically ultimate bending capacities and the design bending resistances from Eurocode 3 Part 1–2 rules and its respective French National Annex (FN Annex).
Findings
The current design expressions revealed to be over conservative when compared with the obtained numerical results. It was possible to observe that the FN Annex is less conservative than the general prescriptions, the first having a better agreement with the numerical results.
Originality/value
Following the previous comparisons, new fire design formulae are analysed. This new methodology, which introduces minimum changes in the existing formulae, provides at the same time safety and accuracy when compared to the numerical results, considering the occurrence of local, distortional and lateral-torsional buckling phenomena in these members at elevated temperatures.
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Carlos Couto, Élio Maia, Paulo Vila Real and Nuno Lopes
The purpose of this paper is to assess whether the adaptation to fire of current proposals/design methodologies at normal temperature is capable of producing accurate predictions…
Abstract
Purpose
The purpose of this paper is to assess whether the adaptation to fire of current proposals/design methodologies at normal temperature is capable of producing accurate predictions of resistance for the out-of-plane stability of tapered beams.
Design/methodology/approach
The adaptation of these methodologies to fire has been done by accounting for the reduction in steel material properties with the temperature. Results were then compared to FEM calculations by performing GMNIA analyses to determine the ultimate strength of the numerical models and to ascertain the validity and accuracy of the adapted methodologies.
Findings
Although all methodologies produce safe results at normal temperatures, only the general method is recommended for the safety verification at elevated temperatures, although the data points were overly conservative. This investigation demonstrates the need of proper and accurate design methods for tapered beams at elevated temperatures, which should be the subject of future developments.
Research limitations/implications
The research in this paper is limited to the adaptation of existing room temperature design methods to fire. Therefore, possible assumptions made during the conception of the initial formulae, which may be valid exclusively for 20ºC, may have been disregarded.
Originality/value
For the time being, design methodologies for the safety check of tapered beams for the case of fire are inexistent. This paper investigates the adaptation of existing room temperature design to the fire situation by providing insights on their accuracy level, as well as on how to proceed. Finally, a safe design methodology for tapered beams in case of fire is provided until improved design methods are developed.
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Flávio Arrais, Nuno Lopes and Paulo Vila Real
Steel beams composed of cold-formed sections are common in buildings because of their lightness and ability to support large spans. However, the instability phenomena associated…
Abstract
Purpose
Steel beams composed of cold-formed sections are common in buildings because of their lightness and ability to support large spans. However, the instability phenomena associated to these members are not completely understood in fire situation. Thus, the purpose of this study is to analyse the behaviour of beams composed of cold-formed lipped channel sections at elevated temperatures.
Design/methodology/approach
A numerical analysis is made, applying the finite element program SAFIR, on the behaviour of simply supported cold formed steel beams at elevated temperatures. A parametric study, considering several cross-sections with different slenderness’s values, steel grades and bending diagrams, is presented. The obtained numerical results are compared with the design bending resistances determined from Eurocode 3 Part 1-2 and its French National Annex (FN Annex).
Findings
The current design expressions revealed to be too conservative when compared with the obtained numerical results. It was possible to observe that the FN Annex is less conservative than the Annex E, the first having a better agreement with the numerical results.
Originality/value
Following the previous comparisons, new fire design formulae are tested. This new methodology, which introduces minimum changes in the existing formulae, provides safety and accuracy at the same time when compared to the numerical results, considering the occurrence of local, distortional and lateral torsional buckling phenomena in these members at elevated temperatures.
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Justyna Dobroszek, Paulo Reis Mourão and Maciej Urbaniak
This paper aims to identify purchasing-related costs through the prism of transaction costs and costs of purchasing management activity.
Abstract
Purpose
This paper aims to identify purchasing-related costs through the prism of transaction costs and costs of purchasing management activity.
Design/methodology/approach
The authors conducted a survey among 150 medium and large manufacturing companies in the chemical, automotive and electromechanical industries operating in Central and Eastern European countries. The collected data were analyzed using confirmatory factor analysis.
Findings
The studied companies carry out an integrated purchasing-related cost system. The authors found a statistical significance of the covariances between the pretransaction, transaction and post-transaction costs. In addition, costs that are of particular importance in long-term purchasing transactions were identified. Moreover, the authors identified the costs of quality and support actions as the most significant.
Practical implications
This research details the discussion of costs with consideration for the insights of managers of medium-sized and large companies.
Originality/value
The paper contributes to the knowledge of purchasing-related costs through the lens of the total cost of ownership that influences the purchasing management and the decisions within the buyer-supplier relationship.
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Magno Rogério Gomes, Marina Silva da Cunha, Solange de Cássia Inforzato de Souza and Paulo Jorge Reis Mourão
This article aims to analyze the workers' probabilities of following their parents’ occupational legacy and whether these individuals are paid differently compared to those who…
Abstract
Purpose
This article aims to analyze the workers' probabilities of following their parents’ occupational legacy and whether these individuals are paid differently compared to those who opted for occupations different from their parents, in Brazil.
Design/methodology/approach
To that end, the occupational legacy probability equation was estimated as the quantile wage equations with sample selection bias correction and the wage decomposition for Brazil from the microdata of the National Household Sample Survey (PNAD) of 2014. It was found that families have a strong influence on the process of choosing the careers of their children. The average probability of a young person following the occupational legacy of their parents was 41.63%. This percentage is different when analyzing different groups of individuals, such as being male or female, being in a traditional or single parent family, being in an income household lower or higher per capita.
Findings
The results also confirm the hypothesis that workers who tend to follow the occupational legacy have lower wages than individuals who choose other occupations and that this may cause a “poverty trap” since the lower the salary quantile, the stronger the “trap” as economically disadvantaged young people tend to follow in their parents' footsteps and to contribute to family income they face a tradeoff, opt between work or study, which ends up disrupting their education and forcing young people to entering the job market early, performing secondary occupations with lower income and arduous work, generating a “vicious cycle of poverty”.
Research limitations/implications
Given the database, we are comprised to its most recent version.
Practical implications
This is the first work on Latin American problem of occupational legacy.
Originality/value
This is the first work on Latin American problem of occupational legacy.
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Using archival and primary source evidence, this chapter introduces the first real wage series from 1891 to 1930 for Brazil’s most important immigrant and industrial city, São…
Abstract
Using archival and primary source evidence, this chapter introduces the first real wage series from 1891 to 1930 for Brazil’s most important immigrant and industrial city, São Paulo. This is the first price series, nominal wage series, and real wage series for the city that covers the duration of the Old Republic. While scholars look to Rio de Janeiro evidence to compare Brazil’s cost of living to other southern cone and immigrant-receiving countries, it is preferable to use evidence from the primary destination city. Price deviations between the two cities underscore the need for these series. The results show foodstuff prices increased steadily over the period and more dramatically in the period during and after World War I. Hedonic wage regressions show hourly wages for unskilled, low-skilled, and medium-skilled workers did not increase accordingly. While the decline in real wages tapered off in the 1920s, real wages across skill levels did not recover to prewar levels. This new index suggests the city of São Paulo’s labor market was more integrated with Buenos Aires’s than with Rio de Janeiro’s and that Paulistano real wages did not recover in the 1920s to the extent that they did in other southern cone cities. Given these results, the puzzle as to why migrants continued to flock to the city prove more intriguing. The results also suggest that Vargas-era labor legislation had the potential to greatly improve the lives of the city’s working class, perhaps more so than in other cities.
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Irineu de Brito Jr, Manoel Henrique Capistrano Cunha, Luiz Antonio Tozi, Luiz Augusto Franzese, Márcia Lorena da Silva Frazão and Adriano Bressane
This study, a practice forum article, aims to presents the lessons learned and the development of a discrete event simulation model to support the funerary system management of…
Abstract
Purpose
This study, a practice forum article, aims to presents the lessons learned and the development of a discrete event simulation model to support the funerary system management of São Paulo City, Brazil, during the COVID-19 pandemic.
Design/methodology/approach
A discrete event simulation model was developed by the authors as soon as the pandemic affected the city of São Paulo, Brazil. Based on the model, several scenarios with varying minimum, median and peak demands (i.e. the number of deaths) were tested and evaluated. The lessons learned from the scenario analysis and implementation of the decision-making of the city government of São Paulo are discussed in this article.
Findings
The lessons learned about the coordination, inventory management and other operational characteristics in funerary logistics during the pandemic are shared with a model, which quantifies the demand for vehicles, coffins, graves and teams in the cemeteries in different simulated scenarios.
Practical implications
The São Paulo State Civil Defense used this information during the pandemic to prepare the funerary system of the municipality.
Social implications
The study presents methods to mitigate the sanitary, environmental and psychosocial problems related to the funerary system.
Originality/value
Studies on funerary systems are scarce. This study presents the results that supported the dimensioning of the funerary system during the pandemic and operational lessons about the logistics to support decision-making in future events.
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Alexandre F. S. Andrada and Mauro Boianovsky
This chapter investigates the political and economic contexts of the controversy about the causes of the increase of income concentration in Brazil during the 1960s. That was the…
Abstract
This chapter investigates the political and economic contexts of the controversy about the causes of the increase of income concentration in Brazil during the 1960s. That was the most important economic debate that took place under the military dictatorship that ran the country from 1964 to 1985. The perceived sharp increase in income inequality posed a challenge to the economic legitimation of the military regime, which had by the early 1970s achieved high rates of economic growth. This chapter discusses the apparent paradox of relatively open economic debate during a period of political repression, as well as its international dimension as reflected in the role played by institutions such as the World Bank.