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Article
Publication date: 1 December 2004

Herbert De Gersem, Markus Wilke, Markus Clemens and Thomas Weiland

Certain sophisticated boundary conditions offer powerful modelling features for many electrotechnical models. Their application, however, wipes out the particular structure of the…

Abstract

Certain sophisticated boundary conditions offer powerful modelling features for many electrotechnical models. Their application, however, wipes out the particular structure of the system matrices which occurs when structured grids are applied. In this paper, this effect is prevented by considering the unconstrained system together with additional constraint equations or by projecting the algebraic system using an oblique or orthogonal projector. The numerical tests indicate that the efficiency of sparse iterative solvers can be preserved even in the presence of complicated boundary relations. The described projections are also advantageous for formulations derived for unstructured grids.

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 June 2001

Markus Clemens, Markus Wilke and Thomas Weiland

Transient eddy current formulations based on the Finite Integration Technique (FIT) for the magneto‐quasistatic regime are extended to include motional induction effects of moving…

Abstract

Transient eddy current formulations based on the Finite Integration Technique (FIT) for the magneto‐quasistatic regime are extended to include motional induction effects of moving conductors with simple geometries by different approaches. A new regularization of the formulation using discrete grad‐div augmentation of the curlcurl formulation is presented and tested. To improve the implicit time integration process, several schemes for an error controlled variable time step selection are presented and for the repetitive solution of the arising large sparse systems of equations a sparse direct solver is compared to iterative methods such as a preconditioned conjugate gradient method and a new algebraic multigrid solver, which is aware of the curlcurl nullspace.

Details

COMPEL - The international journal for computation and mathematics in electrical and electronic engineering, vol. 20 no. 2
Type: Research Article
ISSN: 0332-1649

Keywords

Article
Publication date: 1 April 2006

Mariana Ion, Herbert De Gersem, Markus Wilke and Thomas Weiland

To propose trigonometric interpolation in combination with the sliding‐surface technique for modeling rotation in electrical machine models discretised by the finite integration…

Abstract

Purpose

To propose trigonometric interpolation in combination with the sliding‐surface technique for modeling rotation in electrical machine models discretised by the finite integration technique (FIT).

Design/methodology/approach

Locked‐step, linear and trigonometric interpolation techniques are developed for coupling the stator and rotor model parts of an electrical machine model.

Findings

Linear and trigonometric interpolation should be preferred over the locked‐step approach. Three‐machine models with sliding‐surface coupling discretised by the FIT result in efficient and reliable models.

Originality/value

The introduction of sliding‐surface techniques in the FIT, the trigonometric interpolation used in combination, the application of the FIT for simulating electrical machines.

Details

COMPEL - The international journal for computation and mathematics in electrical and electronic engineering, vol. 25 no. 2
Type: Research Article
ISSN: 0332-1649

Keywords

Article
Publication date: 1 January 2006

Herbert De Gersem, Mariana Ion, Markus Wilke, Thomas Weiland and Andrzej Demenko

To propose trigonometric interpolation in combination with both sliding‐surface and moving‐band techniques for modelling rotation in finite‐element electrical machine models. To…

Abstract

Purpose

To propose trigonometric interpolation in combination with both sliding‐surface and moving‐band techniques for modelling rotation in finite‐element electrical machine models. To show that trigonometric interpolation is at least as accurate and efficient as standard stator‐rotor coupling schemes.

Design/methodology/approach

Trigonometric interpolation is explained concisely and put in a historical perspective. Characteristic drawbacks of trigonometric interpolation are alleviated one by one. A comparison with the more common locked‐step linear‐interpolation and mortar‐element approaches is carried out.

Findings

Trigonometric interpolation offers a higher accuracy and therefore can outperform standard stator‐rotor coupling techniques when equipped with an appropriate iterative solver incorporating Fast Fourier Transforms to reduce the higher computational cost.

Originality/value

The synthetic interpretation of trigonometric interpolation as a spectral‐element approach in the machine's air gap, the efficient iterative solver combining conjugate gradients with Fast Fourier Transforms. The unified application to both sliding‐surface and moving‐band techniques.

Details

COMPEL - The international journal for computation and mathematics in electrical and electronic engineering, vol. 25 no. 1
Type: Research Article
ISSN: 0332-1649

Keywords

Article
Publication date: 19 June 2007

Georg Wimmer, Thorsten Steinmetz and Markus Clemens

A combination of both time step adaptivity and spatial mesh adaptivity is presented for transient magneto‐quasistatic fields.

Abstract

Purpose

A combination of both time step adaptivity and spatial mesh adaptivity is presented for transient magneto‐quasistatic fields.

Design/methodology/approach

Error controlled time step adaptivity is achieved using an implicit integration scheme and the spatial mesh resolution is adapted in each time step in order to effectively resolve the appearing and disappearing local transient saturation effects and eddy current layers. Two spatial refinement strategies are considered, the red‐green refinement leading to a regular mesh and the red refinement leading to an irregular mesh. Numerical results for 2d nonlinear magneto‐dynamic problems are presented.

Findings

An algorithm is proposed which computes the solution of a transient magnetostatic problem given a user prescribed error tolerance for the time stepping and the spatial refinement. The red refinement leading to irregular meshes requires projection techniques in the iterative conjugate gradient solver. However, the algorithm with red‐green refinement turns out to perform faster since the projection is too expensive.

Originality/value

The combination of error controlled time stepping and spatial adaptivity is firstly established in electromagnetic field computation.

Details

COMPEL - The international journal for computation and mathematics in electrical and electronic engineering, vol. 26 no. 3
Type: Research Article
ISSN: 0332-1649

Keywords

Book part
Publication date: 16 August 2005

David De Cremer and Tom R. Tyler

Respect is an important indicator of intragroup status, and it can influence within-group behavior. Being respected by other group members indicates a positive standing within the…

Abstract

Respect is an important indicator of intragroup status, and it can influence within-group behavior. Being respected by other group members indicates a positive standing within the group that is relevant to two important identity concerns: belongingness and social reputation. Belongingness refers to the extent to which a person feels included in the group, and social reputation refers to how other in-group members evaluate a person. We review a series of studies that show that respect indeed communicates information relevant to these identity concerns, and as such influences a person's sense of affiliation, self-esteem, and cooperation (all variables considered to be important for the viability of groups). In addition, we also discuss whether the source of respect (i.e., peers vs. authority), culture, and group size matter in influencing these group-related variables. Finally, some implications for research on groups are discussed.

Details

Status and Groups
Type: Book
ISBN: 978-1-84950-358-7

Book part
Publication date: 25 July 2008

Leigh Plunkett Tost, Morela Hernandez and Kimberly A. Wade-Benzoni

We review previous research on intergenerational conflict, focusing on the practical implications of this research for organizational leaders. We explain how the interaction…

Abstract

We review previous research on intergenerational conflict, focusing on the practical implications of this research for organizational leaders. We explain how the interaction between the interpersonal and intertemporal dimensions of intergenerational decisions creates the unique psychology of intergenerational decision-making behavior. In addition, we review the boundary conditions that have characterized much of the previous research in this area, and we examine the potential effects of loosening these constraints. Our proposals for future research include examination of the effect of intra-generational decision making on intergenerational beneficence, consideration of the role of third parties and linkage issues, investigation of the effects of intergenerational communications and negotiation when generations can interact, examination of the role of social power in influencing intergenerational interactions, investigation of the interaction between temporal construal and immortality striving, and exploration of the ways in which present decision makers detect and define the intergenerational dilemmas in their social environments.

Details

Research in Personnel and Human Resources Management
Type: Book
ISBN: 978-1-84855-004-9

Content available
Book part
Publication date: 18 November 2016

Abstract

Details

Social Recruitment in HRM
Type: Book
ISBN: 978-1-78635-695-6

Book part
Publication date: 5 April 2012

Vibeke Vad Baunsgaard and Stewart Clegg

This chapter explores dominant ideologies theoretically in an organizational setting. A framework is developed to advance our understanding of how ‘dominant ideological modes of…

Abstract

This chapter explores dominant ideologies theoretically in an organizational setting. A framework is developed to advance our understanding of how ‘dominant ideological modes of rationality’ reflect predictability through the reproduction of accepted truths, hence social order in organization. Dominant ideological modes of rationality constitute professional identity, power relations, and rationality and frame prevailing mentalities and social practices in organization. It is suggested that members’ categorization devices structure and constrain social practices. Supplementing the existent power literature, the chapter concludes that professional identity produces rationality, power and truth – truth being the overarching concept assembled through the rationalities assembled in professional members’ categorization devices. Research and managerial implications are discussed.

Details

Rethinking Power in Organizations, Institutions, and Markets
Type: Book
ISBN: 978-1-78052-665-2

Keywords

Article
Publication date: 30 March 2012

Jesper Clement, Mette Skovgaard Andersen and Katherine O'Doherty Jensen

The purpose of this paper is to contribute to the understanding of disagreement between companies and consumers with respect to misleading information and to make suggestions as…

1468

Abstract

Purpose

The purpose of this paper is to contribute to the understanding of disagreement between companies and consumers with respect to misleading information and to make suggestions as to how the conflict might be resolved.

Design/methodology/approach

Based on qualitative research methods, the authors discuss possible grounds for controversies with respect to product information and present a possible framework, inspired by the work of Boltanski and Thévenot, for examining these controversies.

Findings

An analysis of arguments shows that consumer representatives and companies, not surprisingly, agree on general moral principles as, for instance, the importance of not lying about the product; however they tend to disagree about where the boundaries between acceptable and misleading information should be drawn in practice. The findings point to the fact that the differences might partly be explained by Boltanski and Thévenots' “orders of worth” and that this classification would seem to provide a fruitful tool for identifying the character and basis of differences of opinions regarding whether or not product information is deemed to be misleading and hence form the basis for a new tool in the management toolbox for testing potentially misleading information.

Research limitations/implications

The data behind the analysis are limited and retrieved in a Danish environment, for which reason more research should be carried out in order to broaden the perspectives of the research.

Practical implications

To reduce controversies the paper proposes a reciprocal recognition of the particular order of worth from which an assessment is made.

Originality/value

Qualitative methods, in this case the combination of qualitative interviews combined with an analysis of arguments, shed light on the core problem concerning misleading information.

Details

Qualitative Market Research: An International Journal, vol. 15 no. 2
Type: Research Article
ISSN: 1352-2752

Keywords

1 – 10 of 28