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1 – 10 of 47Hugo Entradas Silva and Fernando M.A. Henriques
The purpose of this paper is to verify the applicability and efficiency of two statistical methods to obtain sustainable targets of temperature and relative humidity in historic…
Abstract
Purpose
The purpose of this paper is to verify the applicability and efficiency of two statistical methods to obtain sustainable targets of temperature and relative humidity in historic buildings located in temperate climates.
Design/methodology/approach
The data recorded along one year in a non-heated historic building in Lisbon (Portugal) was analysed with the two methodologies, EN 15757 and FCT-UNL. To evaluate their adequacy it was calculated the performance index for each target and it was verified the mechanical and biological degradation risks.
Findings
While the use of the two approaches is suitable for temperate climates, there is a higher efficiency of the FCT-UNL methodology, allowing a better response for the three parameters in evaluation.
Research limitations/implications
Despite the better results obtained, the FCT-UNL methodology was only tested for one city; therefore the application to other situations may be required to obtain more robust conclusions.
Practical implications
The effectiveness of the FCT-UNL methodology to obtain sustainable climate targets can lead to important energy conservation in historic buildings and to contribute for the change of old approaches in the preventive conservation area.
Originality/value
This paper provides a comparison between two recent methods. The results can lead to some advances in the science of preventive conservation, interesting to conservators and building physic scientists.
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José Gomes Requeijo, Rogério Puga-Leal and Ana Sofia Matos
The purpose of this paper is to discuss the causes for the discrepancy between the utilization of statistical process control (SPC) in services and manufacturing. Furthermore, an…
Abstract
Purpose
The purpose of this paper is to discuss the causes for the discrepancy between the utilization of statistical process control (SPC) in services and manufacturing. Furthermore, an approach for integrating customer demands and technical aspects of a service is presented. Services are very often characterized by a large number of characteristics, with relatively few observations. This research addresses a methodology based on Z and W charts, proposing it for the control of service features. An example associated with service provision is presented to illustrate the computation of Z and W as well as its interpretation.
Design/methodology/approach
The shortcomings of traditional control charts are stated and compared with the control charts for Z and W. An example illustrates how to utilize these charts, their ability to monitor several characteristics simultaneously, along with a continuous monitoring of process capability.
Findings
The proposed approach allowed the representation of several process characteristics in the same charts, even when those characteristics are not collected with the same periodicity. The Z and W charts are dimensionless and can be applied whenever it is possible to estimate process parameters, being an interesting approach to be utilized in Phase 2 of SPC. The difficulty for identifying the existence of non-random patterns emerges as the major shortcoming for these charts.
Research limitations/implications
The proposed approach is a contribute to overcoming the discrepancy that persists between the utilization of SPC in services and manufacturing. Nevertheless, service production and consumption are frequently simultaneous, which constitutes an issue hard to deal with that is not fully addressed in this piece of research. Furthermore, the Z charts also present some disadvantages, notably an increased difficulty for analyzing the existence of non-random patterns, which worsens as increases the number of products/quality characteristics to be checked.
Practical implications
The proposed charts are very flexible and provide a rational utilization of resources. In fact, the representation of several processes is possible, along with the traditional analysis of patterns, thus providing an effective approach for controlling services processes.
Social implications
Several quantitative approaches that have been utilized in manufacturing for a long time are still scarce in services. However, services play a major role in modern economies, being clear that improvements in service provision might have a direct impact on society.
Originality/value
The approach was based on the utilization of Z/W with samples, but it can be extended to individual observations or even to the control of discrete variables. Additionally, a methodology for process capability analysis in real-time is also proposed.
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Seyed Milad Komsionchi Eslamzadeh, António Grilo, Pedro Espadinha-Cruz, João Paulo C. Rodrigues and José Pedro Lopes
The purpose of this research is to review literature about the performance assessment (PA) in urban fire departments (FDs) to gain state-of-the-art of the fire departments'…
Abstract
Purpose
The purpose of this research is to review literature about the performance assessment (PA) in urban fire departments (FDs) to gain state-of-the-art of the fire departments' performance assessment (FDPA) and identify its most applied methods and indicators.
Design/methodology/approach
A five-stage structured literature review (SLR) is conducted to review the FDPA-related studies; then, the statistical analysis is applied to reveal more information from the extracted data and design a general framework for FDPA.
Findings
The systematic literature review resulted in 336 independent variables for FDPA and finding the data envelopment analysis (DEA) as the most applied FDPA method among the mathematical and statistical models in the reviewed papers. By using analysis outcomes, a general conceptual framework for FDPA is proposed.
Research limitations/implications
The reviewed studies were limited to assessments at the strategic level and urban fire protection services.
Practical implications
The results of this research can support fire protection service managers, decision-makers, PA researchers and academicians to have a better understanding of FDPA and state-of-the-art in this field.
Originality/value
A considerable number of studies have been done about the FDPA to provide methods to improve the efficiency and effectiveness of FDs. Although there are reviews about PA in fire service areas, to the best of our knowledge, no study has been done about FDPA.
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Inês A. Ferreira, J.P. Oliveira, Joachim Antonissen and Helena Carvalho
This paper aims to identify the impacts of wire and arc additive manufacturing (WAAM) technology on the green supply chain management (GSCM) performance. Also, it intends to…
Abstract
Purpose
This paper aims to identify the impacts of wire and arc additive manufacturing (WAAM) technology on the green supply chain management (GSCM) performance. Also, it intends to identify the most essential WAAM capabilities.
Design/methodology/approach
An exploratory case study related to a metallurgical company using WAAM technology to repair metallic components was developed. A research framework to identify WAAM production capabilities and the different GSCM performance criteria was proposed based on the current state of the art. Primary qualitative data provided evidence for developing seven propositions relating WAAM capabilities to GSCM performance.
Findings
The paper provides empirical evidence relating to how WAAM production capabilities impact the different performance criteria of the GSCM performance. The results show that “relative advantage” and “supply-side benefits” are critical capabilities developed through WAAM. Furthermore, most of the capabilities regarding “relative advantage” and “supply-side benefits” promote a higher GSCM performance.
Research limitations/implications
This research was carried out using a single case study research design and using qualitative data. Thus, future works are encouraged to test the propositions empirically using quantitative methodologies.
Practical implications
The case study findings support that most WAAM production capabilities promote a higher GSCM performance. Managers could use this research to understand the capabilities developed by this fusion-based additive manufacturing (AM), become aware of the implications of new technology adoption on the supply chain environmental externalities, and develop new business models based on the WAAM capabilities.
Originality/value
This research contributes to expanding the state-of-the art related to WAAM technology by evidencing the relationship between adopting this fusion-based AM technology and green supply chain practices. Also, it provides a set of seven propositions that could be used to theorise the impacts of WAAM adoption on the GSCM performance.
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Rui F. Martins, Alexandre Fernandes, Gonçalo Lóios and António Ginjeira
The purpose of this paper is to assess the fatigue life of different sizes of HyFlex CM™ endodontic files when submitted to planar or to non-planar curvatures, and to two…
Abstract
Purpose
The purpose of this paper is to assess the fatigue life of different sizes of HyFlex CM™ endodontic files when submitted to planar or to non-planar curvatures, and to two different rotational speeds, namely 500 rpm or 250 rpm. The influence of superimposing back and forth motion to rotational bending of endodontic files was also assessed.
Design/methodology/approach
In all, 64 HyFlex CM™ files of different sizes, namely ref. 0.04/20, 0.06/20, 0.04/35 and 0.06/35, were submitted to rotational bending tests at two different rotational speeds. The planar radius of curvature imposed to the endodontic files was about 4.5 mm, along an angle of 45°, in order to simulate an apical canal that would induce severe loading to the files during clinical treatment. Additionally, 11 Hyflex CM™ files ref. 0.04/20 were submitted to rotational bending tests at 500 rpm inside a mandible first molar manufactured through selective laser melting (SLM), aiming to simulate non-planar curvatures of a real tooth canal.
Findings
When considering planar curvature, the endodontic file ref. 0.06/20, tested at 250 rpm, has shown the highest fatigue resistance (4,185 revolutions, 1,004 seconds), while the lowest fatigue resistance was registered for instrument ref. 0.04/35 submitted to 500 rpm (747 revolutions, 89 seconds). Hence, depending on the rotational speed, surface finish and the size of the endodontic files tested (taper and tip’s diameter), significant differences in fatigue resistance were noticed. If non-planar curvatures were considered, the minimum fatigue resistance was equal to 107 seconds, and back and forth motion allowed extending the minimum fatigue lifetime to 140 seconds.
Originality/value
The fatigue resistance of endodontic files is frequently determined through in vitro fatigue tests carried out under single planar curvature or eventually under double planar curvatures. However, non-planar loadings are frequently induced on endodontic instruments when treating root canals with severe multiplanar curvatures. In the research herein presented, a mandible first molar was 3D printed by using the SLM technique in an AISI 316 L stainless steel and more realistic experimental fatigue tests were carried out.
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Suzana Paula Gomes Fernando da Silva Lampreia, José Fernando Gomes Requeijo, José António Mendonça Dias, Valter Martins Vairinhos and Patrícia Isabel Soares Barbosa
The application of condition-based maintenance on selected equipment can allow online monitoring using fixed, half-fixed or portable sensors. The collected data not always allow a…
Abstract
Purpose
The application of condition-based maintenance on selected equipment can allow online monitoring using fixed, half-fixed or portable sensors. The collected data not always allow a straightforward interpretation and many false alarms can happen. The paper aims to discuss these issues.
Design/methodology/approach
Statistical techniques can be used to perform early failure detection. With the application of Cumulative Sum (CUSUM) Modified Charts and the Exponentially Weighted Moving Average (EWMA) Charts, special causes of variation can be detected online and during the equipment functioning. Before applying these methods, it is important to check data for independence. When the independence condition is not verified, data should be modeled with an ARIMA (p, d, q) model. Parameters estimation is obtained using the Shewhart Traditional Charts.
Findings
With data monitoring and statistical methods, it is possible to detect any system or equipment failure trend, so that we can act at the right time to avoid catastrophic failures.
Originality/value
In this work, an electro pump condition is monitored. Through this process, an anomaly and four stages of aggravation are forced, and the CUSUM and EWMA modified control charts are applied to test an online equipment monitoring. When the detection occurs, the methodology will have rules to define the degree of intervention.
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Florinda Matos and Celeste Jacinto
Recent developments in additive manufacturing (AM) technology have emphasized the issue of social impacts. However, such effects are still to be determined. So, the purpose of…
Abstract
Purpose
Recent developments in additive manufacturing (AM) technology have emphasized the issue of social impacts. However, such effects are still to be determined. So, the purpose of this paper is to map the social impacts of AM technology.
Design/methodology/approach
The methodological approach applied in this study combines a literature review with computer-aided content analysis to search for keywords related to social impacts. The content analysis technique was used to identify and count the relevant keywords in academic documents associated with AM social impacts.
Findings
The study found that AM technology social impacts are still in an exploratory phase. Evidence was found that several social challenges of AM technology will have an influence on the society. The topics associated with fabrication, customization, sustainability, business models and work emerged as the most relevant terms that can act as “pointers” to social impacts.
Research limitations/implications
The research on this subject is strongly conditioned by the scarcity of empirical experience and, consequently, by the scarcity of data and publications on the topic.
Originality/value
This study gives an up-to-date contribution to the topic of AM social impacts, which is still little explored in the literature. Moreover, the methodological approach used in this work combines bibliometrics with computer-aided content analysis, which also constitutes a contribution to support future literature reviews in any field. Overall, the results can be used to improve academic research in the topic and promote discussion among the different social actors.
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Susana Duarte and V. Cruz Machado
The purpose of this research work is to propose an assessment framework to evaluate businesses in terms of the implementation of a green and lean organization’s supply chain.
Abstract
Purpose
The purpose of this research work is to propose an assessment framework to evaluate businesses in terms of the implementation of a green and lean organization’s supply chain.
Design/methodology/approach
A conceptual framework was developed for the assessment of green and lean implementation. The framework was designed using key criteria to identify green and lean initiatives. This led to the development of guidelines for each criterion, and the development of a scoring method. A multiple case study of five different organizations in the automotive industry was conducted to validate the conceptual framework.
Findings
The study reveals that high scores are derived from a good interaction between green and lean implementation in these companies. The results confirm that the initiatives considered in the conceptual framework were appropriate to represent the green and lean assessment framework.
Research limitations/implications
The case study was developed in five organizations. Validation of the model is not based on quantitative techniques. The sample size is too small. More study is need in different industry sectors.
Practical implications
The proposed model can be the basis for further research on green and lean concepts, contributing to the understanding of green and lean implementation. With this assessment method, managers can evaluate their business in relation to the implementation of green and lean supply chain initiatives.
Originality/value
To the author’s knowledge, this paper is the first to provide an assessment framework to evaluate an organization’s supply chain in terms of green and lean implementation.
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Ricardo Barbosa, Romeu Vicente and Rui Santos
This paper aims to investigate vulnerability factors that influence thermal comfort in residential buildings in the context of climate change and variability, as well as adaptive…
Abstract
Purpose
This paper aims to investigate vulnerability factors that influence thermal comfort in residential buildings in the context of climate change and variability, as well as adaptive strategies that can be adopted. There is a need for research that systematically addresses factors influencing thermal comfort in the context of climate change.
Design/methodology/approach
Using a vulnerability framework, this paper reviews existing literature to identify factors driving impacts to comfort, as well as strategies to increase adaptive capacity in buildings. Data were collected from several sources including international organizations, scientific journals and government authorities, following an initial Web-based subject search using Boolean operators.
Findings
Significant impacts can be expected in terms of thermal comfort inside buildings depending on four vulnerability factors: location; age and form; construction fabric and occupancy and behaviour. Despite the fact that the majority of the existing studies are technically driven and spatially restricted, there is strong evidence of interdependencies of scales in managing vulnerability and adaptive capacity.
Practical implications
Results from this review emphasise the importance of balance mitigation with adaptation regarding new building design and when retrofitting old buildings. The factors identified here can also be used to assist in construction of simplified tools such as a vulnerability index that helps in identifying the most vulnerable buildings and dwellings and assist in retrofit decisions.
Originality/value
The paper offers critical insight regarding implications in building design and policy in a vulnerability framework.
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Hossein Safari, Elham Razghandi, Mohammad Reza Fathi, Virgilio Cruz-Machado and Maria do Rosário Cabrita
The purpose of this study is to clarify the relationship between getting quality awards by companies and their financial performance in Iran's business.
Abstract
Purpose
The purpose of this study is to clarify the relationship between getting quality awards by companies and their financial performance in Iran's business.
Design/methodology/approach
In the first step, the relationship between awards scores and financial performance by canonical correlation analysis was examined. Then, binary and multinomial logistic regression was used to determine the degree of impact of each financial performance measure on getting quality awards. Finally, two forecasting functions were explored: the probability of achieving quality awards and the probability of achieving different levels of these awards.
Findings
Based on the analyzed data of 112 companies through canonical correlation analysis, there was a weak relationship between financial performance and getting quality awards. Also, by using logistic regression, no result was found to prove the impact of financial performance measures on getting Iran's national quality awards. It can be concluded that conceptually, deployment of excellence organizational models will not result in favorable outcomes, especially in the financial scope. Also, practically, excellence models have not been well deployed in Iranian companies, or these models do not fit to Iran's business environment. Organizational culture may not be consistent with quality.
Originality/value
Quality awards are given to qualified companies following the establishment of models of excellence such as the European Foundation for Quality Management (EFQM). The main novelty of this research is to clarify the relationship between getting quality awards by companies and their financial performance in Iran's business.
Details