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A method based on the minimization of the constitutive error has been successfully applied to finite element formulations of Maxwell equations. Error based techniques present a number of appealing characteristics, including the possibility of providing an estimation of the error distribution and to split the equation system in two decoupled subsystems. However, except for very simple cases, a direct numerical translation of the boundary conditions can cause a number of drawbacks: on one side the lack of symmetry and positive definition of the matrix, on the other side the impossibility of splitting the unknowns. This paper is aiming to discuss the problem and to propose a technique to effectively impose a wide class of boundary conditions within the framework of error based formulations. To show the performance of the technique, some examples are proposed.

The purpose of this paper is to present the use of the compensation theorem (CT), well known in the analysis of linear electric networks, to compute sensitivity of the performance functions used in the robust design or tolerance analysis of electromagnetic devices.

The CT is first illustrated in the case of a simple field analysis problem. Then, using numerical simulations, the effectiveness of compensation approach for assessing impact of the small modification of material properties is shown. The numerical simulations are performed with a finite elements code based on an integral formulation.

The complexity of additional computations to assess the effect of small variations involved in sensitivity analysis can be reduced.

The method can be applied only to linear systems; in addition, although compensation applies to any variations, the reduction of computational complexity is achieved only for small variations, giving localized effects.

The method proposed in the paper can speed up the computations of sensitivity arrays in the robust design and tolerance analysis of electromagnetic device, when numerical methods are applied.

The use of CT in field computations is not new, but its adoption in the sensitivity computation is new to the best knowledge of authors.

Gives a bibliographical review of the error estimates and adaptive finite element methods from the theoretical as well as the application point of view. The bibliography at the end contains 2,177 references to papers, conference proceedings and theses/dissertations dealing with the subjects that were published in 1990‐2000.

The paper presents an efficient modeling technique for the fluxset magnetic field sensor. Using separate numerical solutions for the electric and magnetic fields, an equivalent SPICE circuit is extracted in the postprocessing phase. The main contribution of the paper is the technique used to model the distributed capacitive effects in insulation between coils, by concentrating them in an “Extended II scheme”, an infinite circuit which is optimally reduced to a finite one. The results are in qualitative agreement with the experimental ones.

The paper describes an efficient method to extract the B‐H nonlinear characteristic from the experimental flux‐current Φ‐I data obtained using a non‐uniform magnetic field device. Both functions are monotonically piecewise linear approximated with the same number of breakpoints. The method was successfully applied to characterize the ribbon core material of a fluxset magnetic field sector. In this case the hysteresis loop and the lumped magnetic circuit were extracted. Comparison with experimental results validates the proposed method.

The purpose of this paper is to present a numerical approach for the computation of 3D magnetic fields in rotating electrical machines. The technique is suitable for the computation of flux densities and forces in the end windings of large synchronous turbo generators (TG).

The magnetostatic FEM model of the generator end windings is carried out for different displacements of the rotor axis to the stator magnetomotive force (MMF) axis. The method is based on a parallel integral formulation allowing to substantially reduce the computational effort.

The computational model requires only the discretization of magnetic materials and conductors and is fast enough for carrying out 3D analyses on a time scale fast enough for the needs of the designer. As far as the present application is concerned, the analysis of a synchronous generator in the class of 300‐400 MVA has shown that the most stressed elements of the armature conductors are those closer to the stator ends. The study demonstrates that the maximum stress component on the end windings is axial and is achieved when the MMF is aligned to the direct axis.

The present approach combining an efficient integral formulation, the sparsification of the relevant matrices and the parallel implementation of the related algorithms gives rise to an original computational tool that allows a more accurate description of the machine in comparison to other numerical simulations that can be found in the literature.

The purpose of this paper is to identify and describe the most prominent research areas connected with “Big Data” and propose a thorough definition of the term.

The authors have analysed a conspicuous corpus of industry and academia articles linked with Big Data to find commonalities among the topics they treated. The authors have also compiled a survey of existing definitions with a view of generating a more solid one that encompasses most of the work happening in the field.

The main themes of Big Data are: information, technology, methods and impact. The authors propose a new definition for the term that reads as follows: “Big Data is the Information asset characterized by such a High Volume, Velocity and Variety to require specific Technology and Analytical Methods for its transformation into Value.”

The formal definition that is proposed can enable a more coherent development of the concept of Big Data, as it solely relies on the essential strands of current state-of-the-art and is coherent with the most popular definitions currently used.

This is among the first structured attempts of building a convincing definition of Big Data. It also contains an original exploration of the topic in connection with library management.

As triumphantly announced in journals and magazines, a la Fukuyama, late capitalism and its contingent logic of neoliberalism (ostensibly) reigns supreme, exploiting each site it encounters with precision. According to this fantasy of capitalism's seamless and ultimate triumph, domination is produced as inevitable, social struggle and revolution, a utopian dream. Yet, what many have seen since the 1990s is that this narrative requires military mobilizations of different kinds (i.e., “the war on terror” has become of late the reason thousands are being killed daily in Afghanistan and Iraq).

The Museo Archeologico Nazionale di Napoli (MANN, National Archaeological Museum of Naples) is one of the most important archaeological museums in the world. In 2017, MANN launched several projects, such as Father and Son, the first video game made by an archaeological museum, and Ancient Present (Antico Presente), a series of five short films produced by the museum in five different languages and based on different artworks selected from the museum's permanent collections. The idea behind these projects was to ‘bring the museum outside the museum’, with the assumption that some tools may improve the museum's ability to speak and interact with its audiences, both in the spatial sense (outside its physical perimeter) and the temporal dimension (not only during the visit experience, but also before and after it). We have studied these two MANN projects, as this museum has explicitly targeted audience development as one of its main objectives (MANN, 2016, p. 72) and these projects are important examples of how to use new ‘languages’ (the digital and the cinematographic) to start a dialogue with new audiences and to address museum accessibility in a new way.

The significance of feminisms appears and disappears from where you stand. In the 20th century, feminisms of different contexts have been the very basis of struggles for equity and justice at the same as time as they have faced charges of illegitimacy or irrelevance. As in the last century, the current era can be read not as the histories of feminisms only but as chronicles of feminisms intertwined unevenly with other movements for social, political, and economic justice. In this sense, feminisms have disappeared or metamorphosed.¹ Both verbs signify either that many feminisms are not recognizable as some had known or interpreted them to exist, or that they have altered beyond familiar shapes to forms that have displaced or substituted them. These transformations have led to debates on purist and reconstituted versions; these disputes have, in fact, maintained the vitality of feminisms.²