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Presents the use of a 3D eddy current FE procedure for the analysis and design of two different induction machine structures: a radial and an axial machine. In the first case, attention is devoted to the simulation of locked rotor conditions and a linear 3D time harmonic eddy current FE analysis has been employed. The obtained results have been compared to 2D analysis and experimental data. The axial flux machine is analyzed under fixed speed conditions and a 3D time‐stepping and velocity eddy current problems are solved to evaluate machine performances. Different design configurations are analyzed in order to define the best solution.

Shielding of electromagnetic low frequency field can be performed by means of conductive sheets. These sheets have a thickness which is usually two or three orders of magnitude lower than their other dimensions, thus their effects must be modeled by means of special numerical techniques. In this paper, two integral formulations for the analysis of conductive shields are presented: one is two‐dimensional and is based on a multiconductor system, while the other, three‐dimensional, is based on a finite formulation of electromagnetic fields. Once these analysis tools have been introduced, this paper presents the study of different shielding systems and a problem of optimal exploitation of conductive material.

The purpose of this paper is to present an approach to design passive loop systems in order to reach good performances.

The optimization has been performed by means of the MATLAB optimization toolbox “Gatool” which solves the optimization problems with a genetic algorithm.

Several configurations have been analyzed by varying the number of loops from 2 to 15, whose geometry has been chosen by the genetic algorithm. Considering a five loops configuration, along the reference path it is possible to obtain a shielding factor almost constant and equal to 3.5.

The optimized configurations have been compared with a practical employed layout composed of 17 closed loops placed above and around the junction zone. The shielding factors obtained by the six loops configuration are comparable with the ones of the practical layout.

The main aim of this paper is to explain how numerical magnetic field analysis can be adopted for the simulation of the effects generated when a rope fault occurs. In particular, some important aspects are examined regarding the magnetic flaw generated by internal and external rope faults and the capability of 2D and 3D magnetic field solutions to detect the magnetic flaws.

After a first explanation of the non‐destructive approach from the point of view of the many different methods that can be used to perform a test, an introduction about magnetic systems is provided. Then a 3D magnetic simulation, based on finite integrate technique, of the system is performed and the results compared with those obtained by a simpler 2D magnetic finite element analysis. In the 3D simulation real local damage to the rope is considered and the leakage fluxes around it plotted. A parametric simulation was performed by considering variations of the main geometrical parameters that in a real test can affect the results, such as the airgap between the rope and the measuring point (the position of the field sensors) and the radial position of the sensor itself. Finally, experimental results on the real prototype on many different commercial ropes are provided. In this last section an original method to evaluate the signal to noise ratio of the device is presented.

At first, a really good correspondence between 2D and 3D numerical results was observed. Then it was shown that the difference among the sensing capabilities of field probes placed around the rope is reduced when the position of the damage is higher than 90° in respect of the sensor itself. Moreover, when the angular distance between a sensor and a surface damage is higher than 90°, the damage signal provided by the sensor does not practically change.

Although the development method is always the same, the presented results are valid only for the configuration considered here. The experimental results of the signal to noise ratio are reported only for a reduced number of ropes.

The design procedure can be adopted to develop real devices and to identify the best position of the field sensing system. In particular, the paper shows the difference between radial and axial components of the leakage fluxes around the damage and their variation when the defect moves along the device.

The paper shows a methodology based on 2D and 3D numerical magnetic field analysis for the design of a non‐destructive device for metallic ropes with particular attention being given to the influence of field sensor and damage positions.

The paper aims to describe the coupling of magnetostatic finite formulation of electromagnetic field with two integral methods.

The first hybrid scheme is based on Green's function applied to magnetization source while the other one is based on a magnetic scalar potential boundary element method. A comparison of the two techniques is performed on a benchmark case with analytical solution, on a 2D multiply‐connected problem and on an industrial case where measurements are available.

The proposed hybrid approaches have proved to be effective techniques to solve open boundary non‐linear magnetostatic problems. Similar convergence speed with respect to the number of unknowns is found for both schemes

The paper shows the effectiveness of hybrid schemes applied to the finite formulation, assessing their performances on various test cases.

The synthesis of electro‐mechanic actuators is formulated as a constrained optimization problem where some performance function of the device is to be met, subject to the satisfaction of some constraints about its dimensions and supply conditions. The optimization problem is tackled by means of a genetic algorithm coupled to a multi‐objective definition of the objective function that merge together objectives and constraints in one single scalar objective function. A fast magnetic analysis tool has been developed so that the computational cost of the genetic optimization run is acceptable. Some results about the synthesis of a tubular linear motor in two sizes are presented and discussed.

This work aims to present a multilevel optimization strategy based on manifold‐mapping combined with multiquadric interpolation for the coarse model construction.

In the proposed approach the coarse model is obtained by interpolating the fine model using multiquadrics in a small number of points. As the algorithm iterates the response surface model is improved by enriching the set of interpolation points.

This approach allows to accurately solve the TEAM Workshop Problem 25 using as little as 33 finite element simulations. Furthermore, it allows a robust sizing optimization of a cylindrical voice‐coil actuator with seven design variables.

Further analysis is required to gain a better understanding of the role that the initial coarse model accuracy plays in the convergence of the algorithm. The proposed model allows to carry out such analysis by varying the number of points included in the initial response surface model. The effect of the trust‐region stabilization in the presence of manifolds of equivalent solutions is also a topic of further investigations.

Unlike the closely related space‐mapping algorithm, the manifold‐mapping algorithm is guaranteed to converge to a fine model optimal solution. By combining it with multiquadric response surface models, its applicability is extended to problems for which other kinds of coarse model such as lumped parameter approximations for instance are tedious or impossible to construct.

Introduces papers from this area of expertise from the ISEF 1999 Proceedings. States the goal herein is one of identifying devices or systems able to provide prescribed performance. Notes that 18 papers from the Symposium are grouped in the area of automated optimal design. Describes the main challenges that condition computational electromagnetism’s future development. Concludes by itemizing the range of applications from small activators to optimization of induction heating systems in this third chapter.

The purpose of this paper is to present a new concept of passive loop technique called “high magnetic coupling passive loop” (HMCPL) (suitable for buried power lines) along with optimised design parameters.

The optimal design (geometrical displacement and shielding current intensity and phase) for the mitigation of magnetic field produced by flat and trefoil configuration of the power line is carried out by means of genetic algorithm.

Different layouts for the source (flat and trefoil configuration) and the shield (introduction of the phase splitting technique) are designed. The optimization parameters are the coordinates of the shield conductors and the transformer ratio of the magnetic core that couple the source and the shield. Moreover, physical constraints as maximum depth of excavation and geometric interference between cables were introduced in the optimization procedure.

The paper deals with a very new technology for field mitigation called HMCPL. Actually, the base layout of the HMCPL does not need an optimal design. On the other hand, in some applications the base layout cannot be used, therefore, the introduction of an optimal design cannot be avoided. In this paper, the optimal design of several configurations is performed showing that the performances of the HMCPL are very interesting even if the base layout cannot be used.

Healthy food sales have increased in recent decades. Retailers are widening their marketing management approach, including the use of social media to communicate with consumers and to promote healthy food. The purpose of this paper is to investigate European retailers’ social media communication content used to promote healthy food products, by analysing retailers’ Twitter messages and accounts characteristics, retailers’ Twitter messages content on healthy food and retailers’ Twitter accounts orientation on healthy food.

Data include approximately 74,000 tweets sent in 2016 from 90 corporate and brand accounts. The tweets were sent by the top 36 European retailers. Data elaboration includes quantitative content analysis of Twitter messages, which is used to identify healthy food categories’ occurrences and co-occurrences. Then, multiple multivariate-linear regression analyses explore the relation between retailers’ characteristics and healthy food messaging and between the overall content of retailer accounts and a healthy food focus.

The vast majority of retailers’ tweets on healthy food issues mainly address general health and sustainability issues. Tweets about food health and nutrition refer to food types, meals or consumer segments. Tweets about food sustainability refer to general issues. Analysis of retailer accounts shows that the larger the retailer is, the lower the relevance of healthy food. Retailers with high numbers of tweets and followers tend to decrease their attention to healthy food promotion. Compared to retailers with lower revenues, retailers with higher revenues tend to send a higher number of tweets that focus on healthy food but the incidence is lower compared to the overall accounts’ messaging.

As the study focuses on a single category of food products, further research into other categories of retail products may contribute to a wider perspective. Future research may include graphical content/emoticons and extend the analysis to other social media platforms. Finally, social media data allow studies to cover a wide geographical area. However, in order to also value non-English written messaging, this research introduces some approximations in language interpretation.

The research provides insights into how retailers use social media and provides an overview of how retailers manage their social media communication in one of the most promising food product categories. Retailers manage social media communication content cautiously to minimise controversial issues. This study provides insights into the need to more effectively target the increasing number of social media users.

The research approach and findings of this study extend prior research on retailers’ communication management by improving the understanding of retailers’ use of social media and marketing communication content for their key products, focusing on healthy food.