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Permanent magnet (PM) brushless machines equipped with fractional‐slot concentrated‐windings (FSCW) have been receiving considerable attention over the past few years, due to the fact that they have short end‐windings, a high‐slot fill factor, a high efficiency and power density, and good flux‐weakening and fault‐tolerance capabilities. A key design parameter for such machines is the phase winding inductance since this has a significant impact on the performance, as well as on the magnitude of any reluctance torque. The purpose of this paper is to describe a detailed investigation of the various components of the winding inductance in machines equipped with both overlapping and non‐overlapping windings and different slot/pole number combinations. It also examines the influence of key design parameters, which affect the inductance components, with particular reference to the inductances of machines in which all the teeth are wound and those in which only alternate teeth are wound.

The paper analyzes and compares various inductance components which result from different winding configurations.

It is shown that the main component of the winding inductance is the relatively large slot‐leakage component. Both analytical and finite element models are employed and predicted results are validated on several prototype machines.

Such a thorough investigation of the various inductance components for these type of machines has not been presented before. The paper will serve as a good reference for engineers and researchers designing PM machines equipped with FECW.

The purpose of this paper is to provide a comparison of synchronous permanent magnet machine types for wide constant power speed range operation.

A combination of analytical models and finite element analysis is used to conduct this study.

The paper has presented a detailed comparison between various types of synchronous PM machines for applications requiring a wide speed range of constant‐power operation. Key observations include: surface permanent magnet (SPM) and interior permanent magnet (IPM) machines can both be designed to achieve wide speed ranges of constant‐power operation. SPM machines with fractional‐slot concentrated windings offer opportunities to minimize machine volume and mass because of their short winding end turns and techniques for achieving high‐slot fill factors via stator pole segmentation. High back‐emf voltage at elevated speeds is a particular issue for SPM machines, but also poses problems for IPM machine designs when tight maximum limits are applied. Magnet eddy‐current losses pose a bigger design issue for SPM machines, but design techniques can be applied to significantly reduce the magnitude of these losses. Additional calculations not included here suggest that the performance characteristics of the inverters accompanying each of the four PM machines are quite similar, despite the differences in machine pole number and electrical frequency.

The paper is targeting traction applications where a very wide speed range of constant‐power operation is required.

Results presented are intended to provide useful guidelines for engineers faced with choosing the most appropriate PM machine for high‐constant power speed ratio applications. As in most real‐world drive design exercises, the choice of PM machine type involves several trade‐offs that must be carefully evaluated for each specific application.

The paper provides a comprehensive comparison between different types of synchronous PM machines, which is very useful in determining the most suitable type for various applications.

In July 2010, a mandatory European Union (EU) logo for organic food was introduced to strengthen the organic sector by making the identification of organic products easier for consumers. The present study aims to analyse how consumers in five EU countries view a mandatory EU logo for organic food and to give recommendations for agrarian decision makers and market actors in the organic sector.

The study is based on a combination of qualitative and quantitative methods to provide a comprehensive picture of consumer views. Focus group discussions were conducted with consumers in the Czech Republic, Denmark, Germany, Italy and the UK. A subsequent survey with 2,042 participants was carried out to quantify consumer views on key issues and analyse country differences. Finally, the results of the qualitative and quantitative study were brought together.

While the introduction of a mandatory EU logo for organic food was generally welcomed in all countries, trust in the underlying production standards and the inspection system was not very pronounced (except in Italy). The authors conclude that the introduction of the new EU logo should be supported by communication campaigns to make clear what the new logo stands for and remove unfounded consumer concerns regarding the downscaling of standards and the trustworthiness of the inspection system.

To the authors' knowledge, no previous studies exist on consumer views on a mandatory EU logo for organic food. The recommendations drawn from their findings can help to reach the objectives connected with the introduction of the mandatory EU logo.

The purpose of this paper is to acquire sealing properties of supercritical CO₂ (S-CO₂) T-groove seal under ultra-high-speed conditions by thermo-elastohydrodynamic lubrication (TEHL) analysis.

Considering the choked flow effect, the finite difference method is applied to solve the gas state equation, Reynolds equation and energy equation. The temperature, pressure and viscosity distributions of the lubricating film are analyzed, and sealing characteristics is also obtained.

The face distortions induced by increasing rotational speed leads to the convergent face seal gap. When the linear velocity of rotation exceeds 400 m/s, the maximum temperature difference of the sealing film is approximately 140 K, and the viscosity of CO₂ is altered by 17.80%. Near the critical temperature point of CO₂, while the seal temperature increases by 50 K, the opening force of the T-groove non-contact seal enhances by 20% and the leakage rate declines by 80%.

The TEHL characteristics of the T-groove non-contact seal are numerically analyzed under ultra-high-speed, considering the real gas effect and choked flow effect. In the supercritical conditions, the influence of rotational speed, seal temperature, seal pressure and film thickness on sealing performance and face distortions is analyzed.

In this chapter the authors explore some drivers of entrepreneurial intentions using the theory of planned behaviour on a sample of Italian students. Our objective is twofold. First, the study investigates if both perceiving that becoming an entrepreneur is risky and having non-financial career motivations affect university students’ entrepreneurial intentions. Second, it investigates if students’ perception that university education has an effect on their entrepreneurial skills and attitudes and their perception that the university favours and supports entrepreneurship moderate the relationship between cognitive antecedents of intentions (i.e. attitudes, norms and control) and entrepreneurial intentions. This chapter presents an analysis of a sample of more than 1,500 students from the University of Padova (Italy). According to the national ranking, this University – which is one of Italy’s oldest and largest universities – has been classified as the one with the best Faculty of Economics and Statistics in terms of teaching for more than 10 years among 45 Italian public universities. Data from the Global University Entrepreneurial Spirit Students’ Survey (GUESSS) carried out in 2013 was used. Our analysis highlights not only on the importance of individual characteristics, but also on the role of the learning experience students have during their university studies. This means that it is important to consider how much students perceive that their university education has an effect on entrepreneurial skills and attitudes.

This study aims to explore the nature of electronic word-of-mouth (eWOM) and the key drivers of this consumer-generated brand communication, focusing on eWOM in the context of social media communications.

The study uses inductive qualitative design, and the data have been collected via 22 semi-structured interviews with individuals who follow brands on Facebook.

Building on interview data, the paper advances a conception of eWOM in the social media context and highlights that eWOM consists of a broad range of brand-related communications, which include such activities as consuming, commenting, posting and forwarding information. The study also uncovers two major antecedents of eWOM, which are one’s concern for self-presentation and privacy.

Further research could examine additional drivers of brand-related eWOM in the context of Facebook brand pages, and investigate eWOM in other social media platforms.

The findings have two important implications for brand management. Firstly, considering the importance of self-presentation, brands are advised to develop an in-depth understanding of the types of self-image pursued by their target audience. Secondly, given the concerns about privacy on social media, brands may carefully consider and manage the levels of privacy that should apply when communicating with their followers.

The novel insights centre on the individual differences in eWOM activity, and the importance of one’s perceptions of self-image and privacy in explaining these differences. It seems that the propensity to engage in eWOM and the form that this communication takes are the reflections of one’s self-presentation and privacy preferences.

This study aims to investigate whether users’ engagement with a social media platform is affected as they engage in non-sponsored brand-related user-generated content (UGC). The concept of non-sponsored brand-related UGC encapsulates various social media patterns in which individuals choose how to consume, contribute or create brand-related content with no formal brand incentive or control.

The study focuses on the question of how users engage with non-sponsored brand-related UGC on Instagram and assesses the influence of UGC perceived value, using partial least squares variance-based structural equation modeling.

The research shows significant and positive effects of UGC on Instagram users’ intentions to engage with the platform and the influence of UGC perceived value on UGC uses. The findings deepen the understanding of the mechanisms underlying non-sponsored brand-related UGC in consumer engagement marketing, with significant implications for brand managers and the future development of Instagram and other social media platforms.

The UGC functional, social and emotional values are evaluated for their effects on generating the three distinct patterns of consumer online brand-related activities (consumer, contribute and create) in the non-sponsored brand-related UGC context.

The purpose of this study is to determine the sealing performance of face seals by numerical analysis of thermoelastohydrodynamic characteristics of supercritical CO₂ (S-CO₂) spiral groove face seals in the supercritical regime.

The spiral groove face seal was used as the research object. The distribution of lubricating film pressure and temperature was analysed by solving the gas state, Reynolds and energy equations using the finite difference method. Furthermore, the influence law of sealing performance was obtained.

Close to the critical temperature of S-CO₂, face distortions produced by increasing pressure lead to divergent clearance and resulted in reduced opening force. In the state of S-CO₂, the face distortions generated by increasing seal temperature lead to convergent clearance, which enhances the opening force. In addition, near the critical temperature of S-CO₂, the opening force may be reduced by 10%, and the leakage rate of the seal sharply increases by a factor of four.

The thermoelastohydrodynamic characteristics of supercritical CO₂ face seals are illustrated considering the actual gas effect including compressibility, heat capacity and viscosity. Face distortions and sealing performance were calculated under different seal pressures and seal temperatures in the supercritical regime, as well as with N₂ for comparison.

The peer review history for this article is available at: https://publons.com/publon/10.1108/ILT-05-2020-0169/

For this third column in the IT I‐V (information technology interview) series, we interview library systems directors. While library directors (first column) and chief information officers (second column) addressed similar questions from a high‐level administrative perspective, this time we look at the practical aspects of these issues as told by systems directors working closely with the technologies themselves. Some of the questions were: “What challenges do you see libraries experiencing now and in the near future that could be assisted by information technology?”, “What would you like technologists/library automation vendors to work on that you do not see any progress in at this time?”, “What do you see as the ideal relationship between the library and the information technology offices of your campus or government unit?”, and “If you could explain one thing to technologists/library automation vendors that would help communication between you and them, what would it be?”.