Tulio Coelho, Sofia Maria Carrato Diniz and Francisco Rodrigues
To evaluate the temperature-dependency of the Young’s and shear moduli of concrete after exposure to moderately elevated temperatures using the non-destructive impulse excitation…
Abstract
Purpose
To evaluate the temperature-dependency of the Young’s and shear moduli of concrete after exposure to moderately elevated temperatures using the non-destructive impulse excitation technique (IET).
Design/methodology/approach
The study involved heating the concrete up to 225 °C and measuring the dynamic Young’s and shear moduli using the non-destructive technique of impulse excitation, which measures the natural vibration frequency from a mechanical impulse received by an acoustic sensor. The effects of temperature on the dynamic Young’s and shear moduli were analysed and the importance of the spatial variability of the measured values was also verified.
Findings
The study found that even moderately elevated temperatures (below 225 °C) resulted in a significant permanent reduction in the Young’s modulus of concrete (reduction in the range of 23%–36% for the maximum temperature considered in this research) as well as a modest and permanent reduction in the shear modulus of around 6%. It was also observed that spatial variability of the mechanical properties of concrete plays an important role in the measured values; higher dispersion of the results was found for the values of the Young’s and shear moduli of concrete measured along the height of the beam. The non-destructive test method used in this study was found to be extremely useful in the investigation of heat-related damage in concrete structures for its ease of use, low time consumption and accuracy. The results were consistent with the published literature.
Originality/value
This study provides important insights into the temperature-dependent behaviour of the dynamic Young’s and shear moduli of concrete and highlights the significance of proper consideration of the spatial variability of the measured values. The use of a non-destructive test method for continuous acoustic testing during heating and cooling proved to be effective, and the findings contribute to the fields of materials science and civil engineering in understanding the effects of elevated temperatures on concrete properties. The findings confirm that IET can be easily used to gather important information in the condition assessment and rehabilitation of concrete structures after a fire event. Further studies to foster the application of this technique to real structures are suggested.
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Tulio Coelho, Sofia Diniz, Francisco Rodrigues and Ruben Van Coile
This paper aims to investigate the state of the art for the reliability evaluation of reinforced concrete beams in a fire situation. Special emphasis is placed on addressing which…
Abstract
Purpose
This paper aims to investigate the state of the art for the reliability evaluation of reinforced concrete beams in a fire situation. Special emphasis is placed on addressing which parameters were considered probabilistically or deterministically, the prescribed probabilistic models for the assumed stochastic variables, the treatment of the heat transfer mechanism, the quantification of the structural fire performance and the assumed target reliability levels.
Design/methodology/approach
Research papers were identified through a search on the Web of Science, Google Scholar and detailed searches within the journals Journal of Structural Fire Engineering, Fire Technology and Fire Safety Journal, supplemented with references known by the authors.
Findings
Considering the state-of-the-art review, gaps in the literature are identified related to (1) the probabilistic evaluation of shear capacity for standard fires and parametric fires, and bending capacity for parametric fires, (2) the absence of reference fragility curves for immediate design application/code calibration and (3) the specification of target safety levels for reliability-based design.
Originality/value
The lack of research papers gathering studies on the reliability of reinforced concrete beams in fire situation makes it difficult to further develop research in the area. The value of this work lies precisely in the collection of the basic information, making it possible to identify gaps to be addressed in future research and the suggestion of a research framework.
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Wauires Ribeiro de Magalhães and Francisco Rodrigues Lima Junior
This article aims to propose a model to support the assessment and prioritization of risk in manufacturing processes.
Abstract
Purpose
This article aims to propose a model to support the assessment and prioritization of risk in manufacturing processes.
Design/methodology/approach
The model integrates the failure modes and effects analysis (FMEA) criteria with the evaluation procedures of a new hesitant fuzzy linguistic-technique for Order of Preference by Similarity to Ideal Solution (HFL-TOPSIS) variation. A case study evaluating failure risk in a wiring harness assembly process demonstrated the model's applicability. A sensitivity analysis was performed to verify the effect of the variation in the weights assigned to the decision-makers (DMs).
Findings
The failure mode (FM) ranking was FM4 > FM9 > FM17 > FM2>FM8>FM12 > FM16 > FM19 > FM11 > FM3>FM18 > FM15 > FM13 > FM10 > FM14 > FM7 > FM1 > FM5 > FM6. These outcomes suggest that “stripping length less than specified” was the top priority among the 19 FMs evaluated. Sensitivity tests demonstrated the effect of the DMs’ weights on the ranking of FMs. A comparison with FMEA and HFL-TOPSIS demonstrates the model's greater capacity to discriminate levels of risk priority, as it identifies a total of 19 risk levels compared with 9 levels in the other approaches.
Practical implications
The adoption of the proposed model can drive substantial improvements in risk management practices across industries, provided that the organization has a decision-making team experienced with FMEA. Therefore, this approach promotes the continuous improvement of operations and ensures that mitigation actions effectively address critical FMs.
Originality/value
This is the first study to propose a risk evaluation model that accounts for DMs' hesitation in defining criteria weights through linguistic expressions. Additionally, it addresses uncertainty when assessing weights for the DMs’ opinions and considers multiple factors that affect these weights in decision-making for risk prioritization.
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Thais Coutinho Gonçalves Silva, Rosley Anholon, Izabela Simon Rampasso, Osvaldo Luiz Gonçalves Quelhas, Walter Leal Filho, Luis Antonio Santa-Eulalia and Francisco Rodrigues Lima Junior
This article aims to evaluate the integration level of a quality management system (QMS) and an environmental management system (EMS) in a tire manufacturer and propose a guide to…
Abstract
Purpose
This article aims to evaluate the integration level of a quality management system (QMS) and an environmental management system (EMS) in a tire manufacturer and propose a guide to evaluate the integration of these systems in companies.
Design/methodology/approach
The methodological strategies used in this research were literature review; and case study, with interviews to verify professionals' perception about benefits from integration. Data from interviews were analyzed through Technique for Order of Preference by Similarity to Ideal Solution (TOPSIS).
Findings
The results showed that the studied company has a simple level of integration, observing only some low intensity benefits. Thus, it was recommended that the company partially integrate its management systems (MSs) before evolving into something more complex. The literature and the findings of case study were used as basis for proposing a guide to evaluate MS integration.
Originality/value
Lessons learned throughout the study and the suggested guide can support other companies to assess the integration level of their QMS and EMS. Thus, the findings presented here can be useful for researchers and managers.
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Leonardo Keiti de Godoy Tominaga, Vitor William Batista Martins, Izabela Simon Rampasso, Rosley Anholon, Dirceu Silva, Jefferson Souza Pinto, Walter Leal Filho and Francisco Rodrigues Lima Junior
This paper aims to critically analyze the engineering education focused on sustainability in supply chain management, in courses offered by Brazilian higher education institutions.
Abstract
Purpose
This paper aims to critically analyze the engineering education focused on sustainability in supply chain management, in courses offered by Brazilian higher education institutions.
Design/methodology/approach
Topics related to sustainable supply chain management were listed from the literature and used as a framework to gather professors’ opinions on how well these topics are covered in engineering courses offered in Brazil. Data analysis was performed via frequency analysis and comparative ordering using the Fuzzy technique for order preference by similarity to ideal solution technique.
Findings
It was possible to evidence that most of the topics are superficially presented within other subjects and that there are few associated practical activities that enable greater learning. Comparatively, issues related to ISO standards (related to quality and environmental management systems) and compliance with environmental laws, regulations and standards were highlighted. Additionally, it was possible to verify that there is a need for further study on issues related to energy efficiency, worker training and corporate governance.
Originality/value
No similar study was found in the literature. The findings presented in this paper can contribute to the improvement of engineering education in Brazil and other countries.
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Isabel de Jesus Oliveira, Flávio Filipe Sousa Ferreira and Licínia Vanessa Rodrigues Fernandes
This paper aims to disseminate the results of research aiming to identify the prevalence of dysphagia and related clinical factors in nursing home residents.
Abstract
Purpose
This paper aims to disseminate the results of research aiming to identify the prevalence of dysphagia and related clinical factors in nursing home residents.
Design/methodology/approach
A cross-sectional descriptive study was developed, including 99 residents in five nursing homes. A sociodemographic questionnaire and the Gugging Swallowing Screen for dysphagia screening were used for data collection.
Findings
The prevalence of dysphagia was 59.59%. A significant correlation was found between dysphagia and worse scores for fall risk, pressure ulcer, level of independence for activities of daily living and cognitive functioning.
Research limitations/implications
Results should be interpreted carefully due to sample size and specific country context. A larger sample must be achieved in further research.
Practical implications
Nurses must receive proper training to perform systematic dysphagia screening, and it should be considered, given the high prevalence, the inclusion of professionals specially trained for rehabilitating dysphagic residents in nursing home teams.
Social implications
The social and economic burden of dysphagia, in addition to all the implications on the person’s quality of life, requires a differentiated focus on this issue by nursing home managers.
Originality/value
Nursing homes have nurses providing health care; however, trained professionals for dysphagia treatment commonly are not. These results highlight the importance of systematic screening for dysphagia in all residents, thus promoting timely intervention to prevent respiratory and nutritional complications.
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Paula Rodrigues and Francisco Vitorino Martins
The purpose of this paper is to propose a brand equity measurement model in the consumers’ mind. The measurement model separates the perceptual component of the behaviour…
Abstract
Purpose
The purpose of this paper is to propose a brand equity measurement model in the consumers’ mind. The measurement model separates the perceptual component of the behaviour component of individuals in their preferences for brands. That is, as a result of a set of perceptions, consumers create a brand equity that will be realised in loyal behaviour and in their willingness to pay a premium price for a brand.
Design/methodology/approach
A measurement model of brand equity using the methodology of SEM is proposed. Two samples were used, one for the estimation and another one for the validation of the proposed model, with 272 observations each. The sample is constituted by consumers of five denim clothing brands that have their own chain of stores in Portugal.
Findings
Results show that the model is statistically valid and that perceptual aspects should be separated from behavioural aspects in brand equity measurement based on consumers’ mind.
Originality/value
The originality of the model is the division of constructs into perceptual constructs (inputs), and of behaviour constructs (outputs) of brand equity. By doing this, the model tries to answer two important aspects of entrepreneurial management: which are the explanatory variables of brand equity and how could that be translated into an answer, for the consumer.
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Alberto Rodrigues Carvalho and Francisco Catunda Martins
The purpose of this paper is to seek the inner motivations present in immigrants moving from different regions of Brazil to its capital, Brasília. The goal is to find out the…
Abstract
Purpose
The purpose of this paper is to seek the inner motivations present in immigrants moving from different regions of Brazil to its capital, Brasília. The goal is to find out the individuals’ stories, not only the macroeconomic aspects usually studied in migration movements. Also, the authors intend to understand how impacting the process of leaving one’s homeland and loved ones behind can be.
Design/methodology/approach
In this study, ten recent immigrants were interviewed about their inner motivations to migrate to Brasília and the difficulties faced. Their answers were categorized and distributed into charts showing the most relevant parts for the study.
Findings
Two main topics stood out: work and love. The search for a meaningful and rewarding job is a strong enough reason to migrate. Love presents itself as a different reason to migrate, especially when economic and political reasons are the most common motivators. Love has to do with wanting to be with a partner or family. Migration is a time for crisis, mourning can be present and the strangeness of the new place may affect some more than others. All interviewees mentioned the hardships of adapting, be it emotionally or psychologically.
Originality/value
It is a response to the lack of clinical psychology studies about migration in Brazil. The importance of having studies carried out with a more qualitative perspective in the field of migration, in which the focus are the inner motivations of the migrants and what their experiences are.
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Rogério Lopes, Francisco Barros, Francisco Q. de Melo, Nuno V. Ramos, Rafael Cunha, Ricardo Maia, Rui Rodrigues, M.P.L. Parente and P.M.G. Moreira
The vehicle´s body front pillar should absorb most of the striker kinetic energy, while only a fraction of that is absorbed by the door structure. This study aims to discuss the…
Abstract
Purpose
The vehicle´s body front pillar should absorb most of the striker kinetic energy, while only a fraction of that is absorbed by the door structure. This study aims to discuss the aforementioned issue. In this test the striker is a virtual entity. Six uniaxial strain gauges are installed throughout the door. Additionally, contactless 3D digital image correlation (DIC) allows to assess the major door panel’s continuous deformation and strain fields.
Design/methodology/approach
A coach is a large and heavy long-distance passenger transport vehicle. Their structural certification, classifies coaches as M3 Class III vehicles. New coach structures’ designs need analyses of each sub-system for critical pre-validation of the entire structure, aiming driver and passenger carrier safety. Also, a thorough examination due to increased travel speed is needed.
Findings
Experimental pseudo-dynamic (PSD) results were compared and validated using finite element method (FEM) with two pieces of distinct FEM software (Abaqus® and PamCrash®). The time dependent solution was carried out by explicit techniques. Results by FEM and PSD test showed good agreement, evidencing the reliability of the tools selected. Results by PamCrash® were closer to the experimental data.
Practical implications
R-29 is truck-only regulation, however can be adapted to coaches in case of a frontal collision. The present work focuses on the impact behavior of the passenger front door subsystem.
Originality/value
As a first validation the entire structure, the behavior of a vehicle door, under in-plane impacts was studied. The corresponding deformation energy absorbed by the frontal passenger coach door under virtual impacts of a swinging striker was assessed using a PSD approach.