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This paper aims to introduce an alternative for modeling levitation forces between NdFeB magnets and bulks of high-temperature superconductors (HTS). The presented approach should be evaluated through two different formulations and compared with experimental results.

The T-A and H-ϕ formulations are among the most efficient approaches for modeling superconducting materials. COMSOL Multiphysics was used to apply them to magnetic levitation models and predict the forces involved.The permanent magnet movement is modeled by combining moving meshes and magnetic field identity pairs in both 2D and 3D studies.

It is shown that it is possible to use the homogenization technique for the T-A formulation in 3D models combined with mixed formulation boundaries and moving meshes to simulate the whole device’s geometry.

The case studies are limited to the formulations’ implementation and a brief assessment regarding degrees of freedom. The intent is to make the simulation straightforward rather than establish a benchmark.

The H-ϕ formulation considers the HTS bulk domain as isotropic, whereas the T-A formulation homogenization approach treats it as anisotropic. The originality of the paper lies in contrasting these different modeling approaches while incorporating the external magnetic field movement by means of the Lagrangian–Eulerian method.

Semi-active suspension systems with electromagnetic dampers allow energy regeneration and the required control strategies are easier to implement than the active suspensions are. This paper aims to address the application of a tubular linear permanent magnet synchronous machine for a semi-active suspension system.

Classical rules of mechanics and electromagnetics were applied to describe a dynamic model combining vibration and electrical machines theories. A multifaceted MATLAB®/Simulink model was implemented to incorporate equations and simulate global performance. Experimental tests on an actual prototype were carried out to investigate displacement transmissibility of the passive case. In addition, simulation results were shown for the dissipative semi-active case.

The application of the developed model suggests convergent results. For the passive case, numerical and experimental outcomes validate the parameters and confirm system function and proposed methodology. MATLAB®/Simulink results for the semi-active case are consistent, showing an improvement on the displacement transmissibility. These agree with the initial conceptual thoughts.

The use of linear electromagnetic devices in suspension systems is not a novel idea. However, most published papers on this subject outline active solutions, neglect semi-active ones and focus on experimental studies. However, here a dynamic mechanical-electromagnetic coupled model for a semi-active suspension system is reported. This is in conjunction with a linear electromagnetic damper.

This column has always intended to provide in‐depth, comparative reviews of abstracting services, indexes, serial bibliographies, yearbooks, directories, almanacs and other serial tools which would normally be housed in reference departments. For the purposes of this column, reference serials are materials which must meet two rather flexible requirements: they must be useful as reference sources and they must be issued as serials or be titles which are superseded periodically by new editions.

We are over‐impressed just now by the importance of what are usually described as “the working‐classes,” as though there were any classes in this country which did not work with head or hand. There is “the middle‐class,” which is also a working class; and, if truth be told, probably the hardest working class. It knows nothing of the forty‐four hour week, of constantly rising incomes, or of ca' canny methods. This is the class which forms the backbone of the country, and its marked characteristics, as opposed to the manual workers, are its lack of class consciousness and its want of class cohesion. In years that have gone by, the assumption was, of course, that if anyone wore a black coat instead of fustian he must necessarily be in possession of a larger income than the ordinary working man. He became the target of every Chancellor of the Exchequer, who, nervous of offending the working‐classes, thought little or nothing of any injustice which he might place upon those who formed the middle‐class. That criticism bears upon no particular party, but upon all political parties. Correspondence which has recently appeared in our columns suggests that the middle‐class is beginning to realise the disabilities that patience and forbearance have brought upon it in cumulative measure. On the one hand, it forms a reservoir upon which the nation is always able to draw in times of emergency, as the Great War proved; and, on the other, its very pride and its cultivation of the virtue of individualism rob it of cohesion. As a rule, the man of the middle‐class is neither the direct producer of wealth nor even a minor captain of industry. He supplies, however, the intellect and industry without which Labour would be reduced to idleness and Capital would be denied its dividends. In addition, he and his fellows, besides “carrying on,” recruit the great professions, and are mainly responsible for the research which enables science to come to the aid of the manufacturer and workman. The secret of our prosperity is to be found less conspicuously in the foresight and courage of the Capitalist and the skill of the workman than in the trained intelligence and arduous and unremitting labours of those who constitute the middle‐class. We do not underrate the value of Capital or the achievement of Labour, but it cannot be doubted that the most important element in the community consists of those who occupy the midway position between the extremes. No one can enter a factory or an office without being impressed by the important functions which the great middle‐class performs. One of the greatest dangers associated with Sovietism is that its aim is to stamp out the middle‐class. As soon as Trotsky, Lenin, and their associates had successfully asserted their dictatorship, they turned upon what they described as the “bourgeoisie,” determined to extinguish it. What they did not realise was that without the middle‐class, with its trained knowledge, sense of discipline, and power of command, Russia would be reduced to misery. Soviet Russia is the theatre in which the follies of headstrong and ignorant men are illustrated to the world. We shall do well to take warning by its mistakes. The middle‐class in this country represents elements of strength which we cannot spare, and we trust that British statesmen will walk warily lest in these difficult times of financial stress and strain further burdens are pressed upon it which it cannot bear. — The Daily Telegraph.

The attitudes and perceptions of New Zealanders toward current consumerism issues are outlined and compared with four other countries. Many of the opinions expressed are critical of the existing practices of business and appear to be common in the other four countries. The theory of consumer product life cycle suggesting the development of national consumer movements was not supported by the data obtained in New Zealand.

In the last four years, since Volume I of this Bibliography first appeared, there has been an explosion of literature in all the main functional areas of business. This wealth of material poses problems for the researcher in management studies — and, of course, for the librarian: uncovering what has been written in any one area is not an easy task. This volume aims to help the librarian and the researcher overcome some of the immediate problems of identification of material. It is an annotated bibliography of management, drawing on the wide variety of literature produced by MCB University Press. Over the last four years, MCB University Press has produced an extensive range of books and serial publications covering most of the established and many of the developing areas of management. This volume, in conjunction with Volume I, provides a guide to all the material published so far.

The Bureau of Economics in the Federal Trade Commission has a three-part role in the Agency and the strength of its functions changed over time depending on the preferences and ideology of the FTC’s leaders, developments in the field of economics, and the tenor of the times. The over-riding current role is to provide well considered, unbiased economic advice regarding antitrust and consumer protection law enforcement cases to the legal staff and the Commission. The second role, which long ago was primary, is to provide reports on investigations of various industries to the public and public officials. This role was more recently called research or “policy R&D”. A third role is to advocate for competition and markets both domestically and internationally. As a practical matter, the provision of economic advice to the FTC and to the legal staff has required that the economists wear “two hats,” helping the legal staff investigate cases and provide evidence to support law enforcement cases while also providing advice to the legal bureaus and to the Commission on which cases to pursue (thus providing “a second set of eyes” to evaluate cases). There is sometimes a tension in those functions because building a case is not the same as evaluating a case. Economists and the Bureau of Economics have provided such services to the FTC for over 100 years proving that a sub-organization can survive while playing roles that sometimes conflict. Such a life is not, however, always easy or fun.