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Publication date: 1 December 2022

Agnès Vandevelde-Rougale and Patricia Guerrero Morales

This chapter looks at the discursive dimension of the working environment in research and higher education organizations; more specifically at neoliberal managerial discourse and…

Abstract

This chapter looks at the discursive dimension of the working environment in research and higher education organizations; more specifically at neoliberal managerial discourse and at how it participates in shaping the way researchers, teachers and support staff perceive themselves and their experiences. It is based on a multiple case study and combines an intersectional and a socio-clinical approach. The empirical data is constituted by in-depth interviews with women conducted in Ireland and Chile, and includes some observations made in France. A thematic analysis of individual narratives of self-ascribed experiences of being bullied enables to look behind the veil drawn by managerial discourse, thus providing insights into power vectors and power domains contributing to workplace violence. It also shows that workplace bullying may reinforce identification to undervalued social categories. This contribution argues that neoliberal managerial discourse, by encouraging social representations of “neutral” individuals at work, or else celebrating their “diversity,” conceals power relations rooting on different social categories. This process influences one’s perception of one’s experience and its verbalization. At the same time, feeling assigned to one or more of undervalued social category can raise the perception of being bullied or discriminated against. While research has shown that only a minority of incidents of bullying and discrimination are reported within organizations, this contribution suggests that acknowledging the multiplicity and superposition of categories and their influence in shaping power relations could help secure a more collective and caring approach, and thus foster a safer work culture and atmosphere in research organizations.

Article
Publication date: 1 December 1999

P. Dular, J. Gyselinck, F. Henrotte, W. Legros and J. Melkebeek

Two complementary 3D finite element formulations, with either the magnetic field or the magnetic vector potential as unknowns, are developed to deal with the modeling of eddy…

Abstract

Two complementary 3D finite element formulations, with either the magnetic field or the magnetic vector potential as unknowns, are developed to deal with the modeling of eddy currents in electrical steel laminations. The magnetic flux through the flux gates of the conducting region is imposed via the boundary terms of the weak formulations, in a natural way thanks to the use of edge finite elements. The two formulations are applied to a simple 1D eddy current problem with analytical solution. As a practical 3D application example, a T‐joint region of an electrical steel lamination is considered.

Details

COMPEL - The international journal for computation and mathematics in electrical and electronic engineering, vol. 18 no. 4
Type: Research Article
ISSN: 0332-1649

Keywords

Article
Publication date: 21 December 2023

Hongsen You, Mengying Gan, Dapeng Duan, Cheng Zhao, Yuan Chi, Shuai Gao and Jiansheng Yuan

This paper aims to develop a model that reflects the current transformer (CT) core materials nonlinearity. The model enables simulation and analysis of the CT excitation current…

Abstract

Purpose

This paper aims to develop a model that reflects the current transformer (CT) core materials nonlinearity. The model enables simulation and analysis of the CT excitation current that includes the inductive magnetizing current and the resistive excitation current.

Design/methodology/approach

A nonlinear CT model is established with the magnetizing current as the solution variable. This model presents the form of a nonlinear differential equation and can be solved discretely using the Runge–Kutta method.

Findings

By simulating variations in the excitation current for different primary currents, loads and core materials, the results demonstrate that enhancing the permeability of the BH curve leads to a more significant improvement in the CT ratio error at low primary currents.

Originality/value

The proposed model has three obvious advantages over the previous models with the secondary current as the solution variable: (1) The differential equation is simpler and easier to solve. Previous models contain the time differential terms of the secondary current and excitation flux or the integral term of the flux, making the iterative solution complicated. The proposed model only contains the time differential of the magnetizing current. (2) The accuracy of the excitation current obtained by the proposed model is higher. Previous models calculate the excitation current by subtracting the secondary current from the converted primary current. Because these two currents are much greater than the excitation current, the error of calculating the small excitation current by subtracting two large numbers is greatly enlarged. (3) The proposed model can calculate the distorted waveform of the excitation current and error for any form of time-domain primary current, while previous models can only obtain the effective value.

Details

COMPEL - The international journal for computation and mathematics in electrical and electronic engineering , vol. 43 no. 1
Type: Research Article
ISSN: 0332-1649

Keywords

Article
Publication date: 15 June 2020

Stijn Vandevelde, Freya Vander Laenen, Benjamin Mine, Eric Maes, Lana De Clercq, Lies Deckers and Wouter Vanderplasschen

This paper aims to report the findings of an evaluation study concerning the Central Registration Points (CRPs) for drug users in Belgian prisons. CRPs support drug users to link…

Abstract

Purpose

This paper aims to report the findings of an evaluation study concerning the Central Registration Points (CRPs) for drug users in Belgian prisons. CRPs support drug users to link with community-based services.

Design/methodology/approach

The study applied a multi-method approach that involved an exploratory literature review; a secondary analysis of the CRPs’ databases; a qualitative study of the perceptions of a diverse sample of stakeholders with regard to the functioning of CRPs; and a prospective registration study.

Findings

One-third of the clients never attended an outpatient or residential substance abuse service before prison entry. This illustrates that the CRPs managed to reach clients who were not previously reached by (substance abuse) treatment services. All interviewed actors emphasized the added value of the CRPs in terms of informing, contacting, motivating and referring prisoners with a substance abuse problem.

Practical implications

Based on the research findings, two issues seem to be of paramount importance in the successful practice of CRPs: the confidentiality and specific expertise on (substance abuse) treatment. Given the complex situation of drug users in prison, an independent positioning and categorical assistance with drug-specific expertise seem to be essential.

Originality/value

CRPs can be considered to be one of the “building blocks” that contribute to high-quality care and continuity of care for drugs users in detention.

Details

International Journal of Prisoner Health, vol. 17 no. 1
Type: Research Article
ISSN: 1744-9200

Keywords

Article
Publication date: 1 December 2003

Lieven Vandevelde, Johan J.C. Gyselinck, Francis Bokose and Jan A.A. Melkebeek

Vibrations and acoustic noise are some of the fundamental problems in the design and exploitation of switched reluctance motors (SRMs). Adequate experimental and analysis methods…

Abstract

Vibrations and acoustic noise are some of the fundamental problems in the design and exploitation of switched reluctance motors (SRMs). Adequate experimental and analysis methods may help to resolve these problems. This paper presents a theoretical analysis of the magnetic force distribution in SRM and a procedure for calculating the magnetic forces and the resulting vibrations based on the 2D finite element method. Magnetic field and force computations and a structural analysis of the stator have been carried out in order to compute the frequency spectrum of the generalized forces and displacements of the most relevant vibration modes. It is shown that for these vibration modes, the frequency spectrum can be predicted analytically. The theoretical and the numerical analyses have been applied to a 6/4 SRM and an experimental validation is presented.

Details

COMPEL - The international journal for computation and mathematics in electrical and electronic engineering, vol. 22 no. 4
Type: Research Article
ISSN: 0332-1649

Keywords

Article
Publication date: 14 November 2008

Lieven Degroote, Lieven Vandevelde, Bert Renders and Johan Gyselinck

The aim is to develop a nonlinear transformer model to achieve an accurate model to obtain the frequency components of the magnetizing current based on the harmonic voltages at…

Abstract

Purpose

The aim is to develop a nonlinear transformer model to achieve an accurate model to obtain the frequency components of the magnetizing current based on the harmonic voltages at the primary and secondary side. So, it can easily be implemented in a harmonic load‐flow program.

Design/methodology/approach

The transformer model is based on the harmonic balance method. The electric and magnetic equations of the transformer are derived from the electric and magnetic equivalent circuits.

Findings

The transformer model can be easily implemented in a harmonic load‐flow program. The accuracy of the model has been shown by comparing it with a finite element simulation. The transformer model can be used with asymmetrical supply voltages, because different saturation levels of the phases can occur. There is a coupling between the phases which can be concluded out of the asymmetrical currents in the transformer under symmetrical supply voltages.

Research limitations/implications

The transformer model does not consider the iron losses and the interharmonics. In future work the transformer model will be used to study the harmonic losses in distribution networks, so the transformer losses due to these harmonics have to be considered. This can be achieved with a postcalculation process where the magnetic flux density is used to calculate the eddy current losses and the magnetic field intensity will be applied in a static Preisach model to quantify the hysteresis losses.

Practical implications

The model can be used in a harmonic load‐flow program in order to obtain more accurate simulations for the power system analysis and design.

Originality/value

The model presented in this paper is more detailed than similar papers found in literature (saturation of the yokes, coupling between the phases, interaction between different harmonics) and still it takes a brief simulation time.

Details

COMPEL - The international journal for computation and mathematics in electrical and electronic engineering, vol. 27 no. 6
Type: Research Article
ISSN: 0332-1649

Keywords

Article
Publication date: 1 October 2006

Frederik M.L.L. De Belie, Jan A.A. Melkebeek, Lieven Vandevelde, Kristof R. Geldhof and René K. Boel

To provide a discrete‐time nonlinear model for surface permanent‐magnet synchronous machines (SPMSMs) in order to discuss the stability of such machines.

Abstract

Purpose

To provide a discrete‐time nonlinear model for surface permanent‐magnet synchronous machines (SPMSMs) in order to discuss the stability of such machines.

Design/methodology/approach

Through differencing the co‐energy, obtained from a finite element method, the main flux path can be described by a complex reluctance. Furthermore, for a SPMSM, an equivalent circuit is presented that includes the eddy‐current losses and the voltage drops across stator resistance and leakage inductance. The model is transformed to a discrete‐time state‐space model by using a forward rectangular rule. By using a root locus technique, the stability of the new model is discussed.

Findings

From the calculated root locus it is concluded that the stability of a SPMSM is only guaranteed for certain values of the open loop gain. Moreover, by using the forward rectangular rule, it is concluded that a well‐considered time step has to be chosen.

Research limitations/implications

The model considers the fundamental space harmonic components only. Moreover, the saturation of the leakage flux path is neglected.

Practical implications

As the model is formulated in discrete time, it can be used in modern drives where a digital controller is used.

Originality/value

This paper presents an equivalent electrical circuit for SPMSMs that takes into account the saturation of the magnetizing flux paths as well as the magnetic interaction between the two orthogonal magnetic axes.

Details

COMPEL - The international journal for computation and mathematics in electrical and electronic engineering, vol. 25 no. 4
Type: Research Article
ISSN: 0332-1649

Keywords

Article
Publication date: 1 December 2004

J. Gyselinck, L. Vandevelde, J. Melkebeek and P. Dular

This paper deals with the magnetic vector and scalar potential formulation for two‐dimensional (2D) finite element (FE) calculations including a vector hysteresis model, namely a…

Abstract

This paper deals with the magnetic vector and scalar potential formulation for two‐dimensional (2D) finite element (FE) calculations including a vector hysteresis model, namely a vectorized Jiles‐Atherton model. The particular case of a current‐free FE model with imposed fluxes and magnetomotive forces is studied. The non‐linear equations are solved by means of the Newton‐Raphson method, which leads to the use of the differential reluctivity and permeability tensor. The proposed method is applied to a simple 2D model exhibiting rotational flux, viz the T‐joint of a three‐phase transformer.

Details

COMPEL - The international journal for computation and mathematics in electrical and electronic engineering, vol. 23 no. 4
Type: Research Article
ISSN: 0332-1649

Keywords

Article
Publication date: 1 December 2003

J. Gyselinck, P. Dular, L. Vandevelde, J. Melkebeek, A.M. Oliveira and P. Kuo‐Peng

An original and easy‐to‐implement method to take into account movement (motion) in the 2D harmonic balance finite element modelling of electrical machines is presented. The global…

Abstract

An original and easy‐to‐implement method to take into account movement (motion) in the 2D harmonic balance finite element modelling of electrical machines is presented. The global harmonic balance system of algebraic equations is derived by applying the Galerkin approach to both the space and time discretisation. The harmonic basis functions, i.e. a cosine and a sine function for each nonzero frequency and a constant function 1 for the DC component, are used for approximating the periodic time variation as well as for weighing the time domain equations in the fundamental period. In practice, this requires some elementary manipulations of the moving band stiffness matrix. Magnetic saturation and electrical circuit coupling are considered in the analysis as well. As an application example, the noload operation of a permanent‐magnet machine is considered. The voltage and induction waveforms obtained with the proposed harmonic balance method are shown to converge well to those obtained with time stepping.

Details

COMPEL - The international journal for computation and mathematics in electrical and electronic engineering, vol. 22 no. 4
Type: Research Article
ISSN: 0332-1649

Keywords

Article
Publication date: 1 December 2001

Zbigniew Gmyrek and Grzegorz Zwoliński

The commonly used power electronic systems in the drives of electrical machines as well as in the nonlinear receivers, being the transformer’s load, are the main origin of the…

Abstract

The commonly used power electronic systems in the drives of electrical machines as well as in the nonlinear receivers, being the transformer’s load, are the main origin of the deformation in the voltage supply. Due to these, the voltage curve is not sinusoidally variable. In these cases additional power losses take place in the motor and transformer cores which occur due to higher order harmonics of the flux. This paper presents a method to determine the power losses for the core where there are two fluxes in the steel sheet: one with relatively small amplitude and high frequency, and the other one with relatively large amplitude but low frequency.

Details

COMPEL - The international journal for computation and mathematics in electrical and electronic engineering, vol. 20 no. 4
Type: Research Article
ISSN: 0332-1649

Keywords

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