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In recent years, the mechanical industries began to apply many investments in research and technological development to obtain efficient methods to analyze the integrity of structures and prevent disasters and/or accidents, ensuring people’s lives and preventing economic losses. Any structure, whether mechanical or aeronautical, before being put into use undergoes a structural integrity assessment and testing. In this case, non-destructive evaluations are performed, aiming to estimate the degree of safety and reliability of the structure. For this, there are techniques traditionally used such as ultrasonic inspection, X-ray, acoustic emission tests, among other techniques. The traditional techniques may even have a good instrumental apparatus and be well formulated for structural integrity assessment; however, these techniques cannot meet growing industrial needs, even more so when structures are in motion. The purpose of this paper is to demonstrate artificial immune systems (AISs), ate and strengthen the emergence of an innovative technological tool, the biological immune systems and AISs, and these are presented as computing methods in the field of structural health monitoring (SHM).

The concept of SHM is based on a fault detection mechanism used in industries, and in other applications, involving the observation of a structure or a mechanical system. This observation occurs through the dynamic response of periodic measurements, later related to the statistical analysis, determining the integrity of the system. This study aims to develop a methodology that identifies and classifies a signal in normal signals or in faults, using an algorithm based on artificial immunological systems, being the negative selection algorithm, and later, this algorithm classifies the failures in probabilities of failure and degree of fault severity. The results demonstrate that the proposed SHM is efficient and robust for prognosis and failure detection.

The present study aims to develop different fast access methodologies for the prognosis and detection of failures, classifying and judging the types of failures based on AISs. The authors declare that the present study was neither published in any other vehicle of scientific information nor is under consideration for publication in another scientific journal, and that this paper strictly followed the ethical procedures of research and publication as requested.

This study is original by the fact that conventional structural integrity monitoring methods need improvements, which intelligent computing techniques can satisfy. Intelligent techniques are tools inspired by natural and/or biological processes and belong to the field of computational intelligence. They present good results in problems of pattern recognition and diagnosis and thus can be adapted to solve problems of monitoring and identifying structural failures in mechanical and aeronautical engineering. Thus, the proposal of this study demonstrates and strengthens the emergence of an innovative technological tool, the biological immune system and the AIS, and these are presented as computation methods in the field of SHM in rotating systems – a topic not yet addressed in the literature.

The purpose of this work is to comparatively study human resources management (HRM) areas in Brazil, at the national level, analyzing how companies considered labor market and labor relations aspects when building their strategies and when configuring people management models in place in the country (2014–2019), based on local conditions.

The subject was approached through qualitative analysis, encompassing document survey, systematic literature review, specialists' panel discussions, eight focus groups (43 human resources [HR] managers), interviews (16 union members), applying institutional approach to people management.

In regards to labor market and unions, HR areas faced different conditions across Brazilian regions. They have dealt with those influences on their strategic and quotidian decisions in an unstructured fashion. HR areas remain constructed as traditional, adjuvant and far from strategic level. In the institutionalization process – normative isomorphism – a professional HR jargon use was identified. HR areas usually act in collective bargaining, resorting to specialized professionals or consulting companies. During the economic crisis, HR professionals' attitude had a reactive nature, responding to organizations leadership, with little dedication to the emerging context.

This work enables important players like HR managers, union members and specialists in public policies to interpret the institutionalization phenomena of practices related to management, labor market and labor relations in the country.

Understanding the effects of the relations among state, companies and unions allows the different power vectors, acting upon the institutionalization process of people management areas in the Brazilian case, to be outlined.

This study applies the institutional approach to understand the economic and social heterogeneity affecting organizations in Brazil. It enhances the knowledge on HRM areas scope and their articulation toward labor market and relations.

Construction industry (CI) has great prominence for the world economy, and it is expected that, with the use of the innovative technologies and approaches of Industry 4.0 (I4.0), the new industrial paradigm, construction can reach higher levels of productivity. This study aims to develop a model (readiness model) to assess the level of use of I4.0 technologies by the construction sector in Brazil and its most relevant applications.

The methodology used was bibliographic research, design-science research and a survey to validate the model, carried out with 162 companies, considered among the main ones in the sector in Brazil. The literature review revealed 13 technologies of I4.0 applied to construction; hence, the views of industry experts were based on these technologies.

The Digital Advancement Within CoNstruction (DAWN) readiness model was proposed, showing that among the 13 evaluated technologies of I4.0 and their applications, the Brazilian construction companies had a low level of utilization; both high and middle-income companies presented this low level of use; some technologies with a greater number of scientific publications were less used in practice in the Brazilian construction.

The originality and theoretical contribution are to present a readiness model to assess the level of use of I4.0 technologies and their most relevant applications in the CI in countries with an economy similar to Brazil’s, making it possible to measure the level of adoption of these technologies.

The purpose of this paper is to provide information on lubricant contamination by biodiesel using vibration and neural network.

The possible contamination of lubricants is verified by analyzing the vibration and neural network of a bench test under determinated conditions.

Results have shown that classical signal analysis methods could not reveal any correlation between the signal and the presence of contamination, or contamination grade. On other hand, the use of probabilistic neural network (PNN) was very successful in the identification and classification of contamination and its grade.

This study was done for some specific kinds of biodiesel. Other types of biodiesel could be analyzed.

Contamination information is presented in the vibration signal, even if it is not evident by classical vibration analysis. In addition, the use of PNN gives a relatively simple and easy‐to‐use detection tool with good confidence. The training process is fast, and allows implementation of an adaptive training algorithm.

This research could be extended to an internal combustion engine in order to verify a possible contamination by biodiesel.

The purpose of the paper is to provide information on wear debris on oil and vibration analysis as predictive maintenance techniques in reducer.

The estate of a reducer is verified by analyzing the vibration and oil conditions of a test rig under well‐designed conditions utilizing some predictive variables.

According to the vibration and oil analysis it is found out what it was happening into the reducer without disassembling it.

This paper demonstrates the use of oil debris analysis and vibration analysis as a technique that enhances preventive maintenance practices. The paper helps practitioners to utilize these techniques more effectively.

This paper gives information about two predictive maintenance techniques with a test rig.

This paper aims to provide information on wear debris on oil and vibration analysis as predictive maintenance techniques.

The estate of a reducer is verified by analyzing the vibration and oil conditions of a test rig under some variables.

According to the vibration and oil analysis it was found what was happening in the reducer without disassembling it.

This paper gives information about two predictive maintenance techniques with a test rig.

The purpose of this study is to numerically and experimentally investigate the natural convection heat transfer in flat plates and plates with square, trapezoidal and triangular corrugations.

This work is an extension of the previous studies by Verderio et al. (2021a, 2021b, 2021c, 2021d, 2022a). An experimental apparatus was built to measure the plates’ temperatures during the natural convection cooling process. Several physical parameters were evaluated through the experimental methodology. Free and open-source computational tools were used to simulate the experimental conditions and to quantitatively and qualitatively evaluate the thermal plume characteristics over the plates.

The numerical results were experimentally validated with reasonable accuracy in the range of studied RaLP for the different plates. Empirical correlations of Nu¯LPexp=f(RaLP), h¯conv=f(RaLP) and Nu¯LPexp⋅(A/AP)=f(RaLP), with good accuracy and statistical representativeness, were obtained for the studied geometries. The convective thermal efficiency of corrugated plates (Δη), as a function of RaLP, was also experimentally studied quantitatively. In agreement with the findings of Oosthuizen and Garrett (2001), the experimental and numerical results proved that the increase in the heat exchange area of the corrugations has a greater influence on the convective exchange and the thermal efficiency than the disturbances caused in the flow (which reduce h¯conv). The plate with trapezoidal corrugations presented the highest convective thermal efficiency, followed by the plates with square and triangular corrugations. It was also proved that the thermal efficiency of corrugated plates increases with RaLP.

The results demonstrate that corrugated surfaces have greater thermal efficiency than flat plates in heating and/or cooling systems by natural convection. This way, corrugated plates can reduce the dependence on auxiliary forced convection systems, with application in technological areas and Industry 4.0.

The empirical correlations obtained for the corrected Nusselt number and thermal efficiency for the corrugated plate geometries studied are original and unpublished, as well as the experimental validation of the developed three-dimensional numerical code.

The purpose of this paper is to investigate the use of Pinus wood waste in lead adsorption as a remediation technique in aqueous medium and its subsequent use in obtaining synthesis gas.

The capacity of the timber in the lead adsorption was studied in aqueous medium at various pH, determining the amount adsorbed in equilibrium. Then, the same timber was added in a fixed bed, co-current flow of two stage gasifier type, working temperature of 900°C, for obtaining synthesis gas. The synthesis gas composition was evaluated by the spectrophotometry in the infrared region and the gas chromatography and lead content in the ash and gas was determined by the atomic absorption spectrophotometry.

In laboratory tests carried out, the optimal pH for lead removal was pH 4 with 96.15 percent removal rate, reaching equilibrium after 180 min. In pilot scale the lead removal after 72 hours was 96 percent. The average production of syngas was 11.09 m³h⁻¹. For tests with the motor-generator, the best condition occurred with charge of 2.0 kW, wherein gas consumption per kW produced reached 4.86 m³ kW⁻¹, resulting in a 14.81 percent efficiency rate. The gas analysis showed an average concentration of 14.85 percent H₂, 30.1 percent CO₂, and 50.49 percent of atmospheric air. The concentration of lead in the gas was below the limit established by law. Pinus elliottii waste proved to be an excellent adsorbent, with removing more than 96 percent of the Pb ion present in aqueous solution and a starting material in the gasifier to generate synthesis gas.

This paper describes the waste wood application in the treatment of contaminated environments and for obtaining syngas providing a sustainable process.

This paper shows a process that combines the remediation of contaminated environmental with power generation systems, allowing efficient management of contaminated environments.

The purpose of this study is to numerically investigate the geometric influence of different corrugation profiles (rectangular, trapezoidal and triangular) of varying heights on the flow and the natural convection heat transfer process over isothermal plates.

This work is an extension and finalization of previous studies of the leading author. The numerical methodology was proposed and experimentally validated in previous studies. Using OpenFOAM® and other free and open-source numerical-computational tools, three-dimensional numerical models were built to simulate the flow and the natural convection heat transfer process over isothermal corrugation plates with variable and constant heights.

The influence of different geometric arrangements of corrugated plates on the flow and natural convection heat transfer over isothermal plates is investigated. The influence of the height ratio parameter, as well as the resulting concave and convex profiles, on the parameters average Nusselt number, corrected average Nusselt number and convective thermal efficiency gain, is analyzed. It is shown that the total convective heat transfer and the convective thermal efficiency gain increase with the increase of the height ratio. The numerical results confirm previous findings about the predominant effects on the predominant impact of increasing the heat transfer area on the thermal efficiency gain in corrugated surfaces, in contrast to the adverse effects caused on the flow. In corrugations with heights resulting in concave profiles, the geometry with triangular corrugations presented the highest total convection heat transfer, followed by trapezoidal and rectangular. For arrangements with the same area, it was demonstrated that corrugations of constant and variable height are approximately equivalent in terms of natural convection heat transfer.

The results allowed a better understanding of the flow characteristics and the natural convection heat transfer process over isothermal plates with corrugations of variable height. The advantages of the surfaces studied in terms of increasing convective thermal efficiency were demonstrated, with the potential to be used in cooling systems exclusively by natural convection (or with reduced dependence on forced convection cooling systems), including in technological applications of microelectronics, robotics, internet of things (IoT), artificial intelligence, information technology, industry 4.0, etc.

To the best of the authors’ knowledge, the results presented are new in the scientific literature. Unlike previous studies conducted by the leading author, this analysis specifically analyzed the natural convection phenomenon over plates with variable-height corrugations. The obtained results will contribute to projects to improve and optimize natural convection cooling systems.

The objective of this study is to identify research gaps related to skills required for Industry 4.0, considering research in the context of Brazilian undergraduate courses. In this sense, the question of this study was established: What are the educational gaps related to skills required in Industry 4.0 context, considering considering research in the previously mentioned?

To answer this question, the ten top work-related skills required for professionals in Industry 4.0 published by the World Economic Forum were used to perform a systematic literature review. From this review, 100 articles were found in the searched databases. From them, 18 were within the research scope.

Through an analysis of their content, it was possible to verify that, from the 10 skills analyzed, only six were identified in the articles. That is, no research was found for: people management, service orientation, negotiation, and cognitive flexibility. Additionally, there are undergraduate courses that are not considered in current researches and should be analyzed.

The gaps pointed out in this study are relevant to guide future analyzes of the Brazilian educational model and may provide insights for research in other countries.