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The purpose of this paper is to investigate the use of hybrid‐excitation solutions, using contemporaneously permanent magnets and field coils, for DC machines intended to operate as the core of high‐reliability drives in critical applications supplied by batteries (e.g. fire‐extinguishing pumps, smoke blowers, etc.) where a roughly constant speed is required and a minimal use of electronic devices is prescribed to improve overall dependability.

A high‐reliability hybrid‐excitation DC motor, initially designed basing on theoretical considerations, is then analyzed using purposely developed 2D and 3D finite element method (FEM) electromagnetic models under static, dynamic, healthy, and faulty conditions.

The simulation results confirm that properly designed drives employing hybrid‐excitation DC motors may constitute an effective solution for applications requiring a very high reliability under DC supply with limited speed regulation capability.

The methodology employed exhibits the usual limits concerning the accuracy of FEM analysis: hysteresis is neglected, 2D simulations neglect axial component of fields, in 2D dynamic analysis the electrically discontinuous laminated cores are modeled as orthotropic continuous parts, commutator operation is approximated by means of a position‐dependent resistors network, and the excitation current provided by choppers is approximately considered as constant.

Hybrid excitation DC motors, which may be easily manufactured using existing facilities and mature technologies, might provide an interesting solution for emergency drives requiring minimal regulation capabilities and very high reliability under direct DC supply.

Hybrid excitation is not much investigated in the literature especially for DC motors, although such solution may result potentially interesting especially when a limited flux adjustment capability is required.

This paper aims to present the design of a particular non-reactive test rig for combustion swirlers and first stage turbine nozzles. The test rig is required for important experimental activities aimed at the optimization of a specific class of gas turbines.

A multi-disciplinary team performed the design process by following a tailored design approach, which has been developed for the specific case. The design outcomes allowed to build a fully functional test rig to be introduced in a test cell and then to perform preliminary experiments about the fluid dynamic behaviour of the turbine elements.

The followed design approach allowed to efficiently perform the task, by supporting the information exchange among the different subjects involved in both the conceptual and the embodiment design of the test rig. Additionally, the performed experiments allowed to achieve a final configuration that makes the test rig a valuable test case for combustor-turbine interaction studies.

The study described in this paper is focused on the design of a specific test rig, used for first validation tests. However, the achieved results (both in terms of design and test) constitutes the underpinning of the in-depth investigations to be performed in the next steps of the experimental campaign.

To the best of the authors’ knowledge, the present paper is the first one that comprehensively describes the design activity of an experimental test rig for turbine application, also providing indications about the specific methodological procedure used to manage the process.

This paper explores the stereotype of the accountant in Florentine medieval popular culture based on literary works and from a historical perspective. It aims to highlight how stereotypes change with time and represent the cultural and historical evolution of a society. This research challenges Miley and Read (2012), who stated that the foundation of the stereotype was in Commedia dell'arte, an Italian form of improvisational theatre commenced in the 15th century.

The authors applied a qualitative research method to examine the accountant from a medieval popular culture perspective. The analysis consists of two phases: (1) categorisation of the accountant stereotype based on accounting history literature and (2) thematic analysis of The Divine Comedy (1307–1313) and The Decameron (1348–1351). The authors explored a synchronic perspective of historical investigation through a “cross-author” comparison, identifying Dante Alighieri as the first key author of medieval popular culture. During his imaginary journey through The Divine Comedy, Dante describes the social, political and economic context of the Florentine people of the 14th century. Then, with its various folkloristic elements, The Decameron of Giovanni Boccaccio becomes the “manifesto” of the popular culture in the Florentine medieval times.

This study shows the change of the accountant stereotype from the medieval age to the Renaissance. The Divine Comedy mainly connotes a negative accountant stereotype. The 14th century's Florentine gentlemen (“i galantuomini”) are apparently positive characters, with an ordered and clean aspect, but they are accused of being usurers. Dante Alighieri pictures the accountant as a “servant of capitalism”, “dishonest person, excessively fixated with money”, “villain and evil” and “excessively rational”. Giovanni Boccaccio mainly portrays a positive accountant stereotype. The accountant is increasingly more reliable, and this “commercial man” takes a more prestigious role in the society. In The Decameron, the accountant is depicted as a “hero”, “gentleman”, “family-oriented person with a high level of work commitment” and “colourful persona, warm, and emotional”. Overall, the authors provided new evidence on the existence of the accountant stereotype in the Florentine medieval popular.

This study engages with accounting history literature accountants' stereotypes in an unexplored context and time period, providing a base for comparative international research on accounting stereotypes and popular culture. Additionally, it addresses the need for further research on the accountant stereotype based on literary works and from a historical perspective. Therefore, this research also expands the New Accounting History (NAH) literature, focussing on the investigation of the accountant stereotype connotations in the 14th century.