Micaela Ribeiro, Olga Sousa Carneiro and Alexandre Ferreira da Silva
An issue when printing multi-material objects is understanding how different materials will perform together, especially because interfaces between them are always created. This…
Abstract
Purpose
An issue when printing multi-material objects is understanding how different materials will perform together, especially because interfaces between them are always created. This paper aims to address this interface from a mechanical perspective and evaluates how it should be designed for a better mechanical performance.
Design/methodology/approach
Different interface mechanisms were considered, namely, microscopic interfaces that are based on chemical bonding and were represented with a U-shape interface; a macroscopic interface characterized by a mechanical interlocking mechanism, represented by a T-shape interface; and a mesoscopic interface that sits between other interface systems and that was represented by a dovetail shape geometry. All these different interfaces were tested in two different material sets, namely, poly (lactic acid)–poly (lactic acid) and poly (lactic acid)–thermoplastic polyurethane material pairs. These two sets represent high- and low-compatibility materials sets, respectively.
Findings
The results showed, despite the materials’ compatibility level, multi-material objects will have a better mechanical performance through a macroscopic interface, as it is based on a mechanical interlocking system, of which performance cannot be achieved by a simple face-to-face interface even when considering the same material.
Originality/value
The paper investigates the importance of interface design in multi-material 3D prints by fused filament fabrication. Especially, for parts intended to be subjected to mechanical efforts, simple face-to-face interfaces are not sufficient and more robust and macroscopic-based interface geometries (based on mechanical interlocking systems) are advised. Moreover, such interfaces do not raise esthetic problems because of their working principle; the 3D printing technology can hide the interface geometries, if required.
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Ana Elisa Costa, Alexandre Ferreira da Silva and Olga Sousa Carneiro
The performance of parts produced by fused filament fabrication is directly related to the printing conditions and to the rheological phenomena inherent to the process…
Abstract
Purpose
The performance of parts produced by fused filament fabrication is directly related to the printing conditions and to the rheological phenomena inherent to the process, specifically the bonding between adjacent extruded paths/raster. This paper aims to study the influence of a set of printing conditions and parameters, namely, envelope temperature, extrusion temperature, forced cooling and extrusion rate, on the parts performance.
Design/methodology/approach
The influence of these parameters is evaluated by printing a set of test specimens that are morphologically characterized and mechanically tested. At the morphological level, the external dimensions and the voids content of the printed specimens are evaluated. The bonding quality between adjacent extruded paths is assessed through the mechanical performance of test specimens, subjected to tensile loads. These specimens are printed with all raster oriented at 90º relative to the tensile axis.
Findings
The best performance, resulting from a compromise between surface quality, dimensional accuracy and mechanical performance, is achieved with a heated printing environment and with no use of forced cooling. In addition, for all the conditions tested, the highest dimensional accuracy is achieved in dimensions defined in the printing plane.
Originality/value
This work provides a relevant result as the majority of the current printers comes without enclosure or misses the heating and envelope temperature control systems, which proved to be one of the most influential process parameter.
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Barbara de Lima Voss, David Bernard Carter and Bruno Meirelles Salotti
We present a critical literature review debating Brazilian research on social and environmental accounting (SEA). The aim of this study is to understand the role of politics in…
Abstract
We present a critical literature review debating Brazilian research on social and environmental accounting (SEA). The aim of this study is to understand the role of politics in the construction of hegemonies in SEA research in Brazil. In particular, we examine the role of hegemony in relation to the co-option of SEA literature and sustainability in the Brazilian context by the logic of development for economic growth in emerging economies. The methodological approach adopts a post-structural perspective that reflects Laclau and Mouffe’s discourse theory. The study employs a hermeneutical, rhetorical approach to understand and classify 352 Brazilian research articles on SEA. We employ Brown and Fraser’s (2006) categorizations of SEA literature to help in our analysis: the business case, the stakeholder–accountability approach, and the critical case. We argue that the business case is prominent in Brazilian studies. Second-stage analysis suggests that the major themes under discussion include measurement, consulting, and descriptive approach. We argue that these themes illustrate the degree of influence of the hegemonic politics relevant to emerging economics, as these themes predominantly concern economic growth and a capitalist context. This paper discusses trends and practices in the Brazilian literature on SEA and argues that the focus means that SEA avoids critical debates of the role of capitalist logics in an emerging economy concerning sustainability. We urge the Brazilian academy to understand the implications of its reifying agenda and engage, counter-hegemonically, in a social and political agenda beyond the hegemonic support of a particular set of capitalist interests.
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Arthur Rocha-Gomes, Juliana Dara Silva, Thais Angélica Morais, Amanda Rosa da Costa Ferreira, Viviane Cristina Costa, Amanda Escobar Teixeira, Mayara Rodrigues Lessa, Alexandre Alves da Silva, Nísia Andrade Villela Dessimoni-Pinto and Tania Regina Riul
The purpose of this study is to evaluate the nutritional effects in Wistar rats of supplementation with stand-alone saturated fatty acid (SFA) or monounsaturated fatty acid…
Abstract
Purpose
The purpose of this study is to evaluate the nutritional effects in Wistar rats of supplementation with stand-alone saturated fatty acid (SFA) or monounsaturated fatty acid (MUFA), the replacement of SFA by MUFA and the combination of both (SFA + MUFA) over a long period of time (13 weeks).
Design/methodology/approach
In total, 30 Wistar rats were used and randomly assigned to receive (n = 6): control – lab chow; lard (L20%) – lab chow with added lard (20%); olive oil (O20%) – lab chow with added olive oil (20%); lard replacement with olive oil (L20% –O20%) – during six weeks lab chow with added lard (20%) replaced by lab chow with added olive oil (20%) given during the past seven weeks of the trial; lard combination with olive oil (L10% + O10%) – lab chow with added lard (10%) and olive oil (10%). Food and caloric intake, weight gain, food and energy efficiency, body mass index, bone mineral composition and blood biochemistry were evaluated.
Findings
All diets with added fatty acids showed higher energy intake (p < 0.001), weight gain (p = 0.01), accumulation of adipose tissue (p = 0.02) and food and energy efficiency (p = 0.01) compared to the control group. All groups exhibited higher levels of blood triglycerides compared to the control group (p = 0.02). In addition, the L10% + O10% group developed hyperglycemia (p < 0.001); the L group showed higher amounts of non- high density lipoprotein (HDL-c) (p = 0.04); and the L20%−O20% group exhibited high levels of the triglyceride/HDL-c ratio (p = 0.04) in relation to the control.
Originality/value
These results indicate that regardless of the fatty acid type, consumption in large quantities of fatty acids for long periods of time can cause obesity and dyslipidemia.
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Ricardo Terranova Favalli, Alexandre Gori Maia and Jose Maria Ferreira Jardim da Silveira
This paper aims to evaluate the relation between governance and financial efficiency of credit unions in Brazil. The study shows how poor financial efficiency in credit unions may…
Abstract
Purpose
This paper aims to evaluate the relation between governance and financial efficiency of credit unions in Brazil. The study shows how poor financial efficiency in credit unions may result from undesirable configurations in executive management and other variables related to governance.
Design/methodology/approach
The study develops an innovative methodology to classify credit unions according to the level of governance using indicators of representativeness and participation, leadership, management and supervision. This methodology integrates the use of multiple correspondence and cluster analysis. The study then applies stochastic frontier models to analyze how governance affects the indicators of financial efficiency.
Findings
The results highlight that better governance substantially increases the efficiency of credit unions in terms of a higher level of credit operations per institution.
Originality/value
The paper uses a pioneering survey applied by the Central Bank to almost the total population of credit unions in Brazil. The results highlight how to operationalize a subjective and broad concept related to cooperative governance to identify the remarkable impacts of good governance practices on the financial efficiency of credit unions.
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Alexandre Bevilacqua Leoneti, Danilo Vitorino dos Santos, Renato Santos da Silva, Alessandra Henriques Ferreira, Adriano César Pimenta and Sonia Valle Walter Borges de Oliveira
The purpose of this paper is to propose a process management framework for Chemical Waste Treatment Laboratories (CWTL) that can be used as a management tool to identify and…
Abstract
Purpose
The purpose of this paper is to propose a process management framework for Chemical Waste Treatment Laboratories (CWTL) that can be used as a management tool to identify and manage critical process.
Design/methodology/approach
Proposition of a generic classification for categories of chemical waste; use of the ABC analysis as a tool for analysis of priority in relation to the inputs of an CWTL; use of the process matrix (variety vs volume) to identify the key resources required to perform the activities of a CWTL; and use of mapping process techniques to map the processes defined and calculate times.
Findings
The proposed framework was applied to a CWTL at University of São Paulo, Brazil, and showed that the high variability of demand is a significant factor in the management of this laboratory, requiring processes that are flexible to meet this demand. The results showed that the applicability of the production and operations management theories within the scope of process management of CWTLs, proved to be useful tools for improving the treatment efficiency of chemical waste in these facilities.
Originality/value
The novelty of this work is in the fact of using production and operations management tools in the management of CWTLs to propose diagnoses to improve the management of their processes. The proposition of a comprehensive classification for chemical wastes generated in CWTLs is also highlighted.
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Manuela Gonçalves Barros, Marcelo Botelho da Costa Moraes, Alexandre Pereira Salgado Junior and Marco Antonio Alves de Souza Junior
The purpose of this paper is to evaluate the efficiency in financial intermediation and the cost efficiency in banking service of credit unions in Brazil, based on essentially…
Abstract
Purpose
The purpose of this paper is to evaluate the efficiency in financial intermediation and the cost efficiency in banking service of credit unions in Brazil, based on essentially accounting variables, and to analyze the temporal evolution of the efficiency of these cooperatives.
Design/methodology/approach
With a sample of 315 cooperatives over the period from 2007 to 2014, this research uses a two-stage process: application of regression models with panel data to verify which variables are related to the defined outputs, with the reduction of 31 variables to 8 variables in both models; and application of the data envelopment analysis method to obtain an analysis of credit unions’ efficiency.
Findings
The results demonstrate a high level of efficiency in financial intermediation, with low variation over time, associated with a low efficiency in the banking service, in which few cooperatives have remained efficient over time. In addition, the cooperatives with highest efficiency in financial intermediation were also the most efficient in providing services.
Research limitations/implications
This research has some limitations about the capacity of the proxies used to capture the real effect of the variables and assumptions of economic relations resulting in restrictions to generalize the results.
Practical implications
Cooperatives are usually analyzed under just one dimension. By separating the analysis into financial intermediation and banking services, cooperatives that are more efficient in each dimension can be identified, in addition to analyzing the evolution over time. The authors found that efficiency tends to be lower in banking services, and few cooperatives remain at the highest level of efficiency over time in both models.
Social implications
Credit unions provide an important service in the banking and credit market. Therefore, understanding its operation and the characteristics that influence its efficiency allows a better management of the cooperatives themselves and a greater understanding of this important segment of the financial market.
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Over the last years, the olive oil produced in the Mediterranean countries has obtained growing success in international markets. Olive oil has benefited from the growing appetite…
Abstract
Over the last years, the olive oil produced in the Mediterranean countries has obtained growing success in international markets. Olive oil has benefited from the growing appetite of European and World consumers for products that are part of the so-called Mediterranean diet. For centuries, the olive crops were vital for communities that have occupied the territories bordering the Mediterranean Sea. Despite this long historical drive, this chapter analyses changes that took place since the Second World War. It is recognized that in the decades that followed the end of the war the transformation of western agriculture and rural societies together with commercial and cultural transnational connections have accelerated. Even in peripheral areas, such as Portugal, different processes of globalization have developed, making it necessary to identify the mechanisms that have established the connections to distant territories. Focused on the Portuguese case, this chapter examines how olive oil has contributed to inserting this peripheral territory in the global trade network. A path analysis of this crop is used as a lens to observe how various factors (political, ecological, technical, commercial, social and institutional) have been combined to inhibit or stimulate the inclusion of these rural territories in the dynamics of globalization.
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Teresa Cunha Ferreira, David Ordóñez-Castañón and Rui Fernandes Póvoas
This research seeks to provide methodological bases for the identification, documentation and critical reflection of good practices of architectural design in built heritage…
Abstract
Purpose
This research seeks to provide methodological bases for the identification, documentation and critical reflection of good practices of architectural design in built heritage. These are applied explicitly to the School of Porto architects, which express a high sense of pedagogy and community practice in this field. The methodological approach defines the selection criteria for a georeferenced inventory and the procedures for in-depth analysis of adaptive reuse strategies.
Design/methodology/approach
The works included in the inventory were selected according to geographical, chronological, typological, qualitative and quantitative criteria. The cases chosen for in-depth analysis have been studied along four thematic axes to dissect all the intervention processes (previous state, design/construction and final state). This approach is supported by a cross-analysis of different sources (oral, written, graphic) and using drawing as a fundamental research tool.
Findings
The research has collected and disseminated up to 150 works by 44 architects, providing a comprehensive portrait of heritage intervention by the School of Porto over the past decades. The selection of 22 buildings for in-depth documentation reveals a particular sensibility toward the cultural values through a case-by-case approach based in deep knowledge of the preexisting context and the introduction of contemporary additions in continuity and harmonious relation with the environmental and sociocultural context.
Originality/value
This work provides a novel methodology suitable for further extension and adaptation to other case studies, as a first contribution to a more comprehensive “Atlas of Architectural Design in Built Heritage” with European case studies. The research aims to introduce new and deeper perspectives on reference works that may constitute pedagogy for the future practice of architects within contextual, inclusive and sustainable approaches.
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What insights might attending to the cyclical history of colonially imposed environmental change experienced by Indigenous peoples offer to critical intellectual projects…
Abstract
What insights might attending to the cyclical history of colonially imposed environmental change experienced by Indigenous peoples offer to critical intellectual projects concerned with race? How might our understanding of race shift if we took Indigenous peoples' concerns with the usurpation and transformation of land seriously? Motivated by these broader questions, in this chapter, I deploy an approach to the critical inquiry of race that I have tentatively been calling anticolonial environmental sociology. As a single iteration of the anticolonial environmental sociology of race, this chapter focuses on Native (American) perspectives on land and experiences with colonialism. I argue that thinking with Native conceptualizations of land forces us to confront the ecomateriality of race that so often escapes sight in conventional analyses. The chapter proceeds by first theorizing the ecomateriality of race by thinking with recent critical theorizing on colonial racialization, alongside Native conceptualizations of land. To further explicate this theoretical argument, I then turn to an historical excavation of the relations between settlers, Natives, and the land in Rhode Island that is organized according to spatiotemporal distinctions that punctuate Native land relations in this particular global region: the Reservation, the Plantation, and the Narragansett.