The simulation of eddy currents in laminated iron cores by the finite element method (FEM) is of great interest in the design of electrical devices. Modeling each laminate by…
Abstract
Purpose
The simulation of eddy currents in laminated iron cores by the finite element method (FEM) is of great interest in the design of electrical devices. Modeling each laminate by finite elements leads to extremely large nonlinear systems of equations impossible to solve with present computer resources reasonably. The purpose of this study is to show that the multiscale finite element method (MSFEM) overcomes this difficulty.
Design/methodology/approach
A new MSFEM approach for eddy currents of laminated nonlinear iron cores in three dimensions based on the magnetic vector potential is presented. How to construct the MSFEM approach in principal is shown. The MSFEM with the Biot–Savart field in the frequency domain, a higher-order approach, the time stepping method and with the harmonic balance method are introduced and studied.
Findings
Various simulations demonstrate the feasibility, efficiency and versatility of the new MSFEM.
Originality/value
The novel MSFEM solves true three-dimensional eddy current problems in laminated iron cores taking into account of the edge effect.
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Kaoutar Hazim, Guillaume Parent, Stéphane Duchesne, Andrè Nicolet and Christophe Geuzaine
This paper aims to model a three-dimensional twisted geometry of a twisted pair studied in an electrostatic approximation using only two-dimensional (2D) finite elements.
Abstract
Purpose
This paper aims to model a three-dimensional twisted geometry of a twisted pair studied in an electrostatic approximation using only two-dimensional (2D) finite elements.
Design/methodology/approach
The proposed method is based on the reformulation of the weak formulation of the electrostatics problem to deal with twisted geometries only in 2D.
Findings
The method is based on a change of coordinates and enables a faster computational time as well as a high accuracy.
Originality/value
The effectiveness of the adopted approach is demonstrated by studying different configurations related to the IEC 60851-5 standard defined for the measurement of the electrical properties of the insulation of the winding wires used in electrical machines.
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Ewa Wikström, Jonathan Severin, Ingibjorg H. Jonsdottir and Magnus Akerstrom
Process facilitation as part of a complex intervention for changing or improving practices within workplaces is becoming a common work method. The aim of this study was to…
Abstract
Purpose
Process facilitation as part of a complex intervention for changing or improving practices within workplaces is becoming a common work method. The aim of this study was to investigate what characterizes the process-facilitating role in a complex intervention.
Design/methodology/approach
The present study focuses on a complex work environment intervention targeting eight organizational units (workplaces) in the Swedish healthcare sector. The study applies a mixed-method approach and has been carried out in two steps. First, a qualitative process evaluation was performed. Secondly, an evaluation was conducted to see to what extent these identified conditions and mechanisms affected the quantitative intervention effect in term of sickness absence.
Findings
The analysis shows that the facilitating role consisted of three overlapping and partially iterative phases. These phases involved different activities for the facilitating role. Depending on how the facilitating role and the intervention were designed, various supporting conditions were found to significantly affect the outcome of the intervention measured as the total sickness absence.
Research limitations/implications
It is concluded that the facilitation is not static or fixed during the change process. Instead, the facilitation role develops and emerges through the process of support during the different implementation phases.
Practical implications
The facilitative role of performing support is based on a combination of support role activities and expert role activities. The support role focuses on support activities, while the expert role includes capacity building through knowledge- and legitimacy-oriented activities.
Originality/value
This study contributes to earlier research by developing a methodological approach for carrying out process facilitation in complex interventions.
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Stjepan Frljić, Bojan Trkulja and Ana Drandić
The purpose of this paper is to present a methodology for calculating eddy current losses in the core of a single-phase power voltage transformer, which, unlike a standard power…
Abstract
Purpose
The purpose of this paper is to present a methodology for calculating eddy current losses in the core of a single-phase power voltage transformer, which, unlike a standard power transformer, has an open-type core (I-type core). In those apparatus, reduction of core losses is achieved by using a multipart open-type core that is created by merging a larger number of leaner cores.
Design/methodology/approach
3D FEM approach for calculation of eddy current losses in open-type cores based on a weak AλA formulation is presented. Method in which redundant degrees of freedom are eliminated is shown. This enables faster convergence of the simulation. The results are benchmarked using simulations with standard AVA formulation.
Findings
Results using weak AλA formulation with elimination of redundant degrees of freedom are in agreement with both simulation using only weak AλA formulation and with simulation based on AVA formulation.
Research limitations/implications
The presented methodology is valid in linear cases, whereas the nonlinear case will be part of future work.
Practical implications
Presented procedure can be used for the optimization when designing the open-type core of apparatus like power voltage transformers.
Originality/value
The presented method is specifically adapted for calculating eddy currents in the open-type core. The method is based on a weak formulation for the magnetic vector potential A and the current vector potential λ, incorporating numerical homogenization and a straightforward elimination of redundant degrees of freedom, resulting in faster convergence of the simulation.
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Lysann Seifert, Nathan Kunz and Stefan Gold
The purpose of this paper is to map and analyse the literature from 1989 to 2016 on humanitarian supply chain management (SCM) responding to refugees. This literature review…
Abstract
Purpose
The purpose of this paper is to map and analyse the literature from 1989 to 2016 on humanitarian supply chain management (SCM) responding to refugees. This literature review systematically assesses existing literature, thereby highlighting gaps, challenges and directions for future research.
Design/methodology/approach
The authors apply a structured content analysis method which has been recognised as a traceable, systematic and reproducible research tool to analyse qualitative and quantitative aspects of existing literature.
Findings
The relative scarcity of literature implies that the interface of the fields of Humanitarian SCM and refugees has been rarely addressed. More specifically, the quantitative content analysis highlights a dearth of research that focusses on both fields in a well-balanced manner. In particular, empirical, practice-led studies, as well as research on development aid operations are under-represented. The qualitative analysis finds that further research on logistics models as well as technological innovations is necessary to increase data availability, forecast accuracy and the efficiency of (local) supply network operations during disasters.
Research limitations/implications
The review suggests a number of areas in need of future research, proposes possibilities of collaborations between different actors and provides a research agenda for Humanitarian SCM in the context of refugees.
Originality/value
This review is the first to analyse the literature on Humanitarian SCM related to refugees.
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Varuna Dreepaul-Dabee and Verena Tandrayen-Ragoobur
This paper aims to examine the employment effect of the minimum wage in Mauritius, a country that has recently introduced an economy-wide national minimum wage. As women have low…
Abstract
Purpose
This paper aims to examine the employment effect of the minimum wage in Mauritius, a country that has recently introduced an economy-wide national minimum wage. As women have low labor force participation rate and higher unemployment rate compared to men, this study sheds light on the impact of the national minimum wage on male and female employment.
Design/methodology/approach
A conceptual framework based on the labor–leisure model of Blundell et al. (2007) incorporating the minimum wage as an important variable influencing the employment decision of the individual serves as the methodological backdrop of this paper. It applies the difference-in-difference estimation technique and uses micro data from the Continuous Multi-Purpose Household Survey for the period 2017–2019.
Findings
The results show that minimum wage has a significant negative impact on overall employment. With the imposition of the national minimum wage, the probability that an individual, currently earning less than the minimum wage, remains employed is 0.525 lower than that of a worker earning above the minimum wage level. Moreover, using sex-disaggregated data, the analysis demonstrates the negative employment effects of the minimum wage adversely impact women more than men.
Originality/value
This is a first attempt to estimate the effect of the newly introduced national minimum wage on employment in Mauritius. While the effects of a minimum wage vary across different segments of the economy, this study adopts a gender perspective by comparing the impact of the minimum wage on male and female employment.
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Alexandre de Vicente Bittar and Luiz Carlos Di Serio
Micro and small enterprises (MSEs) play a crucial role in the development of any country by generating innovative ideas. However, they face inherent restrictions that hinder their…
Abstract
Purpose
Micro and small enterprises (MSEs) play a crucial role in the development of any country by generating innovative ideas. However, they face inherent restrictions that hinder their innovation capabilities. It is essential to support innovation policies to overcome these barriers and foster innovation. This study aims to explore how innovation policies can reduce barriers to innovation in MSEs using the lens of innovation capabilities.
Design/methodology/approach
Through a multiple case study, the authors examined eight MSEs in São Paulo (Brazil) and five in Florence (Italy) to conduct this study. These countries share a similar level of importance when it comes to MSEs.
Findings
Current innovation policies could be more effective for MSEs if certain barriers they encounter are faced and resolved, such as limited financial resources and a scarcity of qualified workers. These barriers directly affect two key elements of their innovation capability: financial resources and human resources. Therefore, it is essential to develop innovation policies that target these elements directly to enable MSEs to overcome these obstacles and thrive.
Originality/value
This study aims to enhance the knowledge of how innovation policies can help alleviate obstacles to innovation and how they can influence the various components that comprise the innovation capability of MSEs. This research can be valuable for policymakers as it provides insight into which innovation policies impact each aspect of innovation capability, enabling them to choose the most suitable policy based on the specific needs and local circumstances of the MSEs.
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While the value of human capital for technological innovation is well acknowledged, literature on the role of vocational training in corporate innovation is notably scarce. The…
Abstract
Purpose
While the value of human capital for technological innovation is well acknowledged, literature on the role of vocational training in corporate innovation is notably scarce. The purpose of this study is to assess the effect of government support for small and medium-sized enterprise (SME) competencies on Korean firms’ innovation. The author investigates SMEs’ patent applications (supported by the government to varying degrees) while accounting for firms’ market position, ownership and management structure, as well as prior changes in firms’ technologies, products, processes and other characteristics. Alternative hypotheses about management motivation – the “lazy manager”, “career concerns” and “special East Asian institutional constraints” hypotheses – are also evaluated.
Design/methodology/approach
Censored and count data analysis methods are used on a panel of 595 Korean firms covering 2005–2015 from the Korean Human Capital Corporate Survey, Intellectual Property Office and National Investment Commission. A regression discontinuity estimator accounts for potential endogeneity because of support for vocational training at firms.
Findings
Firms receiving training support are more innovative than firms without support, but latent effects may play a role. The regression-discontinuity model suggests that firms that succeeded only marginally in obtaining support had higher innovative output than non-recipients near the eligibility threshold.
Originality/value
The findings of this study establish that government support had the intended effect on SMEs’ technological capacity. This cannot be discounted as a simple crowding-out effect. The author also establishes that management–ownership separation within firms was conducive to innovation, that product competition had an inverse U-shaped effect and that management–ownership separation had a substitutable relationship with competition in overcoming managers’ effort avoidance. The findings support the “lazy manager” hypothesis over the “career concerns” and the “special East Asian institutional constraints” hypotheses.
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Philippos Nikiforou, Thomas Dimopoulos and Petros Sivitanides
The purpose of this study is to investigate how the degree of overpricing (DOP) and other variables are associated with the time on the market (TOM) and the final selling price…
Abstract
Purpose
The purpose of this study is to investigate how the degree of overpricing (DOP) and other variables are associated with the time on the market (TOM) and the final selling price (SP) for residential properties in the Paphos urban area.
Design/methodology/approach
The hedonic pricing model was used to examine the association of TOM and SP with various factors. The association of the independent variable of DOP and other independent variables with the two dependent variables of TOM and SP were investigated via ordinary least squares (OLS) regression models. In the first set of models the dependent variable was TOM and in the second set of models the dependent variable was SP. A sample of N = 538 completed transactions from Q1 2008 to Q2 2019 was used to estimate the optimum DOP that a seller must apply on the current market value of a property in order to achieve highest SP price in the shortest TOM.
Findings
The results of this study also suggest that the degree of overpricing in thin and less transparent markets is higher than that in transparent markets with high property transaction volumes. In mature markets like the USA and the UK where the actual sold prices are published, the DOP is around 1.5% which is much lower than the 11% DOP identified in this study.
Practical implications
It was found that buyers are willing to pay more for the same house in a bigger plot than a bigger house in the same plot. The outcome is that smaller houses sell faster at a higher price per square meter than larger houses. Smaller houses are more affordable than larger houses.
Social implications
There is a large pool of buyers for smaller houses than bigger houses. Higher demand for smaller houses results in a higher price per square meter for smaller houses than the price per square meter for bigger houses. Respectively the TOM for smaller houses is shorter than the TOM for bigger houses.
Originality/value
The database used is unique, from an estate agent located in Paphos that managed to sell more than 27,000 properties in 20 years. This data set is the most accurate information for Cyprus' property transactions.
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Patrick Das, Robert Verburg, Alexander Verbraeck and Lodewijk Bonebakker
Since the 2008 financial crisis, the financial industry is in need of innovation to increase stability and improve quality of services. The purpose of this paper is to explore…
Abstract
Purpose
Since the 2008 financial crisis, the financial industry is in need of innovation to increase stability and improve quality of services. The purpose of this paper is to explore internal barriers that influence the effectiveness of projects within large financial services firms focussing on potentially disruptive and radical innovations. While literature has generally focused on barriers within traditional technology and manufacturing firms, few researchers have identified barriers for these type of firms.
Design/methodology/approach
A framework of internal barriers was developed and validated by means of an explorative case study. Data were collected at a European bank by exploring how innovation is organized and what barriers influence effectiveness of eight innovation projects.
Findings
Six items were identified as key barrier for potentially disruptive and radical innovations (e.g. traditional risk-avoidance focus, and inertia caused by systems architecture). As such, in the sample these were more important than traditionally defined barriers such as sources of finance, and lacking exploration competences.
Research limitations/implications
Based on a small number of projects within one firm, the results highlight the need for more in-depth research on the effects of barriers and how barriers can be overcome within this industry.
Originality/value
The results show that there is a discrepancy between the societal demand for radical change within the financial industry and the ability of large financial services firms to innovate. The study identifies which unique internal barriers hamper potentially disruptive and radical innovation in large financial services firms.