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This study aims to investigate the effect of bismuth addition (up to 30 Wt%) on the microstructure and electrical conductivity of a commercial lead-free alloy (SAC405) near the solder/substrate soldered joint. The system under study is referred in this work as (SAC405 + xBi)/Cu, as Cu is the selected substrate in which the solder was casted. The electrical resistivity of this system was investigated, considering Bi addition effect on the local microstructure and chemical composition gradients within that zone.

Solder joints between Cu substrate and SAC405 alloy with different levels of Bi were produced. The electrical conductivity along the obtained solder/substrate interface was measured by four-point probe method. The microstructure and chemical compositions were evaluated by scanning electron microscopy/energy dispersive spectroscopy analysis.

Two different electrical resistivity zones were identified within the solder interface copper substrate/solder alloy. At the first zone (from intermetallic compound [IMC] until approximately 100 μm) the increase of the electrical resistivity is gradual from the substrate to the solder side. This is because of the copper substrate diffusion, which established a chemical composition gradient near the IMC layer. At the second zone, electrical resistivity becomes much higher and is mainly dependent on the Bi content of the solder alloy. In both identified zones, electrical resistivity is affected by its microstructure, which is dependent on Cu and Bi content and solidification characteristics.

A detailed characterization of the solder/substrate zone, in terms of electrical conductivity, was done with the definition of two variation zones. With this knowledge, a better definition of processing parameters and in-service soldered electronic devices behavior can be achieved.

Currently, there are some finite element head models developed by research groups all around the world. Nevertheless, the majority are not geometrically accurate. One of the problems is the brain geometry, which usually resembles a sphere. This may raise problems when reconstructing any event that involves brain kinematics, such as accidents, affecting the correct evaluation of resulting injuries. Thus, the purpose of this study is to develop a new finite element head model more accurate than the existing ones.

In this work, a new and geometrically detailed finite element brain model is proposed. Special attention was given to sulci and gyri modelling, making this model more geometrically accurate than currently available ones. In addition, these brain features are important to predict specific injuries such as brain contusions, which usually involve the crowns of gyri.

The model was validated against experimental data from impact tests on cadavers, comparing the intracranial pressure at frontal, parietal, occipital and posterior fossa regions.

As this model is validated, it can be now used in accident reconstruction and injury evaluation and even as a design tool for protective head gear.

This study aims to identify how the sustainability of Brazilian Federal Institutes of Education, Science and Technology is implemented.

The research is descriptive and quantitative, and questionnaires were used to collect data, which were applied to the campuses and deans of the 38 IFs. The sample selection resulted from a sampling calculation for a finite population, which considered the five Brazilian regions, reaching 248 respondents. To analyze the collected data, descriptive statistics were used to demonstrate the mean, standard deviation (σ) and coefficient of variation of each of the seven axes of the questionnaire and also of the axes and regions jointly; and the sustainability indicator was defined.

A majority of the analyzed FIs were considered to be medium or highly sustainable. The classifications achieved by the FIs demonstrate that sustainability practices are reasonably present in a significant number of campi and Principals’ Offices.

This study contributes by creating a data collection instrument to measure the sustainability practice, not only in educational institutions but also in any type of institution; and the sustainability indicators created, which make it possible to classify organs and entities in accordance with sustainable initiatives implemented by them.

This study’s authors can highlight the mapping of sustainability implementation in the Brazilian Federal Institutes analyzed, which, owing to the sample used, allows for the verification of similarities and differences in these practices between the five Brazilian regions, in addition to making comparisons possible.

The purpose of this paper is to assess the feasibility of analytical models, specifically the radial basis function method, Akbari–Ganji method and Gaussian method, in conjunction with the finite element method. The aim is to examine the impact of processing parameters on temperature history.

Through analytical investigation and finite element simulation, this research examines the influence of processing parameters on temperature history. Simufact software with a thermomechanical approach was used for finite element simulation, while radial basis function, Akbari–Ganji and Gaussian methods were used for analytical modeling to solve the heat transfer differential equation.

The accuracy of both finite element and analytical methods was validated with about 90%. The findings revealed direct relationships between thermal conductivity (from 100 to 200), laser power (from 400 to 800 W), heat source depth (from 0.35 to 0.75) and power absorption coefficient (from 0.4 to 0.8). Increasing the values of these parameters led to higher temperature history. On the other hand, density (from 7,600 to 8,200), emission coefficient (from 0.5 to 0.7) and convective heat transfer (from 35 to 90) exhibited an inverse relationship with temperature history.

The application of analytical modeling, particularly the utilization of the Akbari–Ganji, radial basis functions and Gaussian methods, showcases an innovative approach to studying directed energy deposition. This analytical investigation offers an alternative to relying solely on experimental procedures, potentially saving time and resources in the optimization of DED processes.

This paper seeks to analyze the relationship between China and the Northeast region of Brazil, aiming to identify how the renewable energy sector is being developed.

The authors analyzed secondary data from the official databases from China-Brazil chambers of commerce to establish the main points related to renewable energy in Brazil's Northeast.

It is possible to notice the main investments, highlighting the wind energy as a more prominent source recently. The authors also point the huge influence from China on Brazil's Northeast energy sector.

It is difficult to identify the amount of Chinese capital due to the large number of mergers and acquisitions that has been taking place in recent years.

Identification of regions that have been receiving investments and the main interests of Chinese investors in the renewable energy sector.

Demonstration of how the renewable energy sector has taken an important turn in Brazil due to Chinese investment.

To evaluate a regional consortium, analyzing its strategies for partnerships with China to help each other in global questions, as is the case of renewable energy.

Numerical simulation of the single point incremental forming (SPIF) processes can be very demanding and time consuming due to the constantly changing contact conditions between the tool and the sheet surface, as well as the nonlinear material behaviour combined with non-monotonic strain paths. The purpose of this paper is to propose an adaptive remeshing technique implemented in the in-house implicit finite element code LAGAMINE, to reduce the simulation time. This remeshing technique automatically refines only a portion of the sheet mesh in vicinity of the tool, therefore following the tool motion. As a result, refined meshes are avoided and consequently the total CPU time can be drastically reduced.

SPIF is a dieless manufacturing process in which a sheet is deformed by using a tool with a spherical tip. This dieless feature makes the process appropriate for rapid-prototyping and allows for an innovative possibility to reduce overall costs for small batches, since the process can be performed in a rapid and economic way without expensive tooling. As a consequence, research interest related to SPIF process has been growing over the last years.

In this work, the proposed automatic refinement technique is applied within a reduced enhanced solid-shell framework to further improve numerical efficiency. In this sense, the use of a hexahedral finite element allows the possibility to use general 3D constitutive laws. Additionally, a direct consideration of thickness variations, double-sided contact conditions and evaluation of all components of the stress field are available with solid-shell and not with shell elements. Additionally, validations by means of benchmarks are carried out, with comparisons against experimental results.

It is worth noting that no previous work has been carried out using remeshing strategies combined with hexahedral elements in order to improve the computational efficiency resorting to an implicit scheme, which makes this work innovative. Finally, it has been shown that it is possible to perform accurate and efficient finite element simulations of SPIF process, resorting to implicit analysis and continuum elements. This is definitively a step-forward on the state-of-art in this field.

The objective of this research is to develop an solution to water management at the scale of buildings, through the technological resources. Automating analysis using 3D models helps increase efficiency in buildings during the operational phase, consequently promotes sustainability.

This study presents a methodology based on Design Science Research to automate water management at building scale integrating BIM-IoT-FM. Data from smart meters (IoT) and the BIM model were integrated to be applied in facilities management (FM) to improve performance of the building. The methodology was implemented in a prototype for the web, called AquaBIM, which captures, manages and analyzes the information.

The application of AquaBIM allowed the theoretical evaluation and practical validation of water management methodology. By BIM–IoT integration, the consumption parameters and ranges for 17 categories of activities were determined to contribute to fulfill the research gap for the commercial buildings. This criterion and other requirements are requirements met in order to obtain the AQUA-HQE environmental sustainability certification.

Traditionally, water management in buildings is based on scarce data. The practical application of digital technologies improves decision-making. Moreover, the creation of consumption indicators for commercial buildings contributes to the discussion in the field of knowledge.

This article emphasizes the investigation of the efficiency of use in commercial buildings using operational data and the use of sustainable consumption indicators to manage water consumption.

Population worldwide has experienced several challenges related to sustainable development, such as scarcity of natural resource, unsustainable consumption, poverty, injustice, violence, social inequality and natural disaster (including floods, tsunami and landslide). These issues interfere in sustainable development and target to achieve societal balance, structuring without compromising economic and environmental resources of future generations. The higher educational institutions are included in this context because they play a role in professional training and in education to promote sustainable practices. The higher educational institutions can assume a prominent position in the 2030 Agenda implementation for sustainable development of the United Nations, especially in the Goals 4 and 10, quality education and reduced inequalities, respectively. The purpose of this research study aims to develop a literature review and analyze the higher educational and sustainable themes, involving the Brazilian scenario.

This research study develops a literature review based on researches that involve higher educational and sustainable themes in the Brazilian scenario. Inclusion criteria are papers in English, with the search equations in their titles, and peer-reviewed papers. Paper publication year was not an exclusion criterion. This research aimed to understand opportunity and challenge processes in the Brazilian higher educational institutions and their actions, so that the Sustainable Development Goals are completely achieved and the 2030 Agenda for sustainable development is fulfilled. For this, a research central question was established: What are the opportunities and the challenges to achieve the 2030 Agenda for sustainable development in the Brazilian higher education?

A total of 636 papers were recovered. The “Higher Education AND Opportunities,” “Higher Education AND Challenge,” “Higher Education AND Challenges,” “Higher Education AND Opportunity,” “Brazilian AND Higher Education” and “Brazil AND Higher Education” search equations found, respectively, 165, 146, 131, 74, 62 and 25 papers, involving 94.8% of the total number of the papers found. The papers recovered enabled the vision of five clusters: policy; inclusion; culture; relationship; and environment, society and economy. The paper analyses found that innovation process, sustainable practical implementation and holistic look, involving professors and students, can allow the 2030 Agenda achievement.

The authors of this research study presented a framework based on the literature analyzed through five clusters: policy; inclusion; culture; relationship; and environment, society and economy, considered from opportunity and challenge perspectives. The authors introduced and discussed the Brazilian higher educations and their opportunities and challenges. The Brazilian panorama was linked with the 2030 Agenda for sustainable development, in specific, with the Goals 4 and 10. Implications of this research study are related to the higher educational opportunities and challenges in policy, inclusive, cultural, sustainable and relationship contexts, involving governmental and nongovernmental sectors, professors and students for the Brazilian educational improvement.

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.