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This paper deals with the application of the surface‐current method to the analysis of electromagnetic devices. The basics of the method are outlined and new developments involving the implementation of automated procedures for the definition of the geometry and sources, the contour subdivision according to suitable error indexes and the upgrading of the magnetic permeability to analyse saturated devices are described. As examples of application, the method is applied to the analysis of a single‐phase step motor and a linear brushless DC motor; the results are discussed and compared with the outputs of corresponding finite‐element method analyses.

The technique for the simulation of the dynamic behaviour of rotating machines presented in the paper is based on an equivalent circuit representation of the magnetic configuration. The circuit parameters are obtained by a preliminary automated sequence of magnetostatic FEM analyses and take into account the local magnetic saturations. The adopted solution technique is based on an invariant network topology approach: its application, presented for the operation analysis of a low‐power synchronous generator, allows a great reduction of the calculation time in comparison with a commercial FEM code for the transient simulation.

The paper presents a methodology in which the slotted regions of electrical machines are replaced by homogeneous regions with anisotropic magnetic permeability. The resulting FEM model is then built and solved in an easy way, because a simplified structure is analyzed, with fixed geometrical characteristics and electrical and magnetic properties depending on the original geometry. The methodology is therefore useful for estimating the machine performances as a function of slot and winding parameters and can be conveniently used at the initial step of the design to perform parametrical analyses and optimizations with uncomplicated procedures for the generation of the FEM model. In order to test the reliability of the method, the FEM results obtained with both the actual configuration and the “smoothed” one must be compared. In the example of application, the proposed methodology is applied to a linear brushless DC motor. The dependence of the accuracy and convergence speed on different “smoothing” strategies is first discussed. Then the obtained results are compared with the ones related to the original slotted configuration. Finally, the correspondence of some important electromagnetic quantities (flux lines distribution, air‐gap flux density and electromagnetic force) is analyzed.

The purpose of this paper is to devise a magnetic field modelling approach suitable for simulating the transient behaviour of a class of electromagnetic systems (particularly linear synchronous motors).

The classical 2D magnetic equivalent circuit (MEC) approach is extended by separately accounting for leakage flux from highly permeable polygonal regions (where the MEC approach is most applicable). It capitalises on the computational efficiency of an MEC approach for regions where the flux can be assumed to be uniformly channelled through a coarse network of “flux tubes” and accounts for leakage flux from these regions by introducing mutual permeances. These mutual permeances are geometry dependent and can be calculated upfront using a surface‐current representation of the magnetomotive force attributed to each flux tube.

As demonstrated with a simple example, the magnetic field solution converges with an increasing subdivision of flux tubes, yielding a transparent trade‐off between simulation time and accuracy.

Using Schwarz‐Christoffel mapping to approximate the mutual permeances is restrictive and introduces unnecessary error. Hence, the use of finite element or boundary element methods to obtain these permeances is under investigation. Furthermore, it is expected that introducing 2D flux tube elements for junction regions would be beneficial.

A novel approach is presented that aims to improve the accuracy of a traditional MEC solution, whilst retaining its computational advantage for the flux that is well channelled. The method has particular merit for the dynamic modelling of linear motors, where the machine's behaviour is dominated by the flux bridging the air gap.

An understanding of consumer behaviour will enable service providers to segment their client base and target specific customer groups with strategies designed to meet their retail needs. Hence, an insight into and understanding of how consumers interact with and evaluate a retail offering will help improve customer service and satisfaction. The purpose of this paper is to examine the changes in consumers' food retail behaviour with regard to the demographic variable of age, based on the older population. This paper focuses on food shoppers aged over 60 years living independently in Northern Ireland. The retail geography in Northern Ireland has changed and whilst affecting all consumers has impacted to a greater degree on older consumers. This and the fact that the over 60 age group is increasing demographically illustrate why this consumer segment is worthy of greater consideration.

A quantitative methodological approach is employed and data are collected using a consumer questionnaire (n=791). The questionnaire is analysed using the Statistical Package for Social Sciences (SPSS) version 15.

The results show that as age increases older consumers' retail buying and food‐related behaviour changes. A decline in patronage of multiple retailers is evident as age increases; as is consumers' perceived value of multi‐purchase promotions and nutritional confidence. Alongside increasing age there is an apparent increase in the use of local shops, the enjoyment gained from shopping, the difficulty experienced in accessing food retail sites and the problems experienced when cooking.

This paper suggests that age may be used to differentiate between customer groups and retailers must take age into consideration when providing a product offering and in retail provision for the elderly consumer.

This paper fulfils a need for information on older consumers' retail behaviour in Northern Ireland and offers advice to food retailers attempting to better serve this increasingly important consumer segment.

The purpose of this research is to investigate the difficulties and challenges faced by the older supermarket consumers in order to form insights into potential ways of applying IT support and design solutions within the supermarket service for older consumers. The rationale for this research stemmed from observations and discussions with supermarkets with regards to the use of IT and better process design for a growing segment of their consumer base.

A mixed research methodology was used for this research. Firstly, an ethnographic approach based on direct observations was felt appropriate as this would offer a visual unbiased view of the processes involved in the shopping experience. Secondly, it was felt that it would be appropriate to support these findings with semi‐structured interviews. The data was clustered to provide contextual awareness of the problems involved within the shopping experience.

The findings indicated a range of areas where senior consumers faced difficulties. One major problem was around understanding where certain products were placed on shelves and why. The other areas of concern were access to products (shelf height), poor signage, labelling and inappropriate portion sizes.

The main research limitation is the small sample size that was studied. Obviously with a much larger sample a wider range of problems would be uncovered. The other area of concern is the fact that studying particular customers invades the privacy of customers that are inadvertently caught up on videos. In future, it may make sense to get participants to film themselves and talk into smart mobiles, recording real‐time data.

The research indicates that it is important for supermarkets to improve signage and customer support, and use IT more freely in most areas. The use of electronic ink signage is a new and important area that they could invest in. This would allow real‐time updates.

As many countries are faced with growing numbers of senior citizens, it is important that their lives are made easier and the shopping experience improved.

There are limited attempts at the use of an ethnographic approach to explore elderly consumers’ shopping experiences in the UK. The existing studies do not look at the practicalities of everyday shopping problems faced by this segment of the population. It also adds value to the retailers’ understanding of the behaviour patterns of this important customer segment, at the same time offering solutions to certain problems such as signage and directions through the utilisation of IT.

The aim of the paper is to explain and clarify the pre-processing for a finite element based wound rotor induction machine model.

The paper presents two algorithms. The first one speeds up the FE-simulations by changing the input parameter permutation scheme only. The second algorithm speeds up the quint-cubic spline parameter calculation by utilizing the continuity conditions between adjacent segments.

The paper provides comparisons of the calculation cost to show the advantages of the presented algorithms.

The algorithms explained in this paper allow a practical application of the finite element based model approach for a wound rotor induction machine. Therefore, this work completes the development of the finite element based wound rotor induction machine model.