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The purpose of this paper is to present an original study of industrial inductors with different air-gap materials in order to reduce the vibration and noise of inductors. Acoustic comfort is an increasingly important factor at the design stage of industrial inductors associated to converters. In addition, power converters in the railway domain are more and more compact and powerful.

Experiments, simulations and test devices were used to determine the main physical phenomena that generate the undesirable audible noise. Electric and vibratory measurements (modal and operational analysis) were compared with the numerical calculations. PWM and sinusoidal supply were taken into account and different prototypes with different materials in the air-gap were built.

This study analyzes and details the origin of the electromagnetic noise due to the vertical mode, in order to reduce the vibration and noise of inductors. A detailed analysis using finite element simulation and experimental measurements of free-free mode or forced mode under electrical excitation was conducted to interpret the vibrations of the structure. In addition, in order to observe trends and the impact of magnetostriction effect, the authors propose a simplified model.

Electric and vibratory measurements (modal and operational analysis) are compared with the numerical calculations.

This paper gives a response about the origin of the noise with different experimental measurements. Changing the air-gap material is beneficial for the deflection of the inductor. However, it has been presented that, following the shape of the inductor, it is beneficial to reduce or increase the stiffness of the material depending on the column height. For a fixed Young’s modulus air-gap, a ratio Column height/air-gap thickness exists, which makes it possible to cancel the deflection.

The horizontal rotational single-sheet tester (RSST) suffers from weaknesses such as the reduced size of test samples, measurement disturbances due to magnetic flux leakage and nonhomogeneity of field in the measurement area. Although the vertical RSST allows to overcome the first two aforementioned drawbacks, the heterogeneity of the field in the test sample remains an issue. In addition, there is still a lack of device standardization to ensure test repeatability, as already is well established with the Epstein frame. This paper aims to investigate the influence of several parameters on the field homogeneity in the test sample.

A fully 3D finite element model of a vertical RSST is developed and used to perform a sensibility study on several geometrical parameters.

The influence of several parameters on the field homogeneity in the test sample, such as the geometrical dimensions of the yokes, the presence or not of holes drilled inside the test sample for B-coil placement as well as the size of the H-coils and B-coils, is addressed.

It is expected that this study will contribute to the optimization and standardization vertical RSSTs.

This paper aims to propose a new design for high-power compact solid-state transformers (SSTs) made with grain-oriented electrical steel (GOES) wound cores that benefit from the natural reduction of iron losses at high temperatures.

An experimental approach, coupled with numerical and analytical investigations, is widely used for proving the validity of the proposed concept.

With cores much hotter than coils, the new design of medium frequency transformers can be used for building compact SSTs that rated powers and common-mode insulation voltages much higher than existing ones with similar efficiencies.

The thermal design must provide a large difference between core and coil temperatures in a reasonable volume.

The increasing number of intermittent renewable sources place electric grid stability at risk. Smart nodes, made of SSTs, improve the global grid stability because they are able to provide real-time control of energy fluxes at critical points. In railway applications, high-power SST cells can be distributed along the train providing a larger volume for passengers.

The increasing part of electricity in a flexible grid requires performant and high-power SSTs made with components that have an environmental footprint as low as possible.

This paper proves that the design of high-power transformers with GOES wound cores much hotter than coils is possible. It proposes also a thermal equivalent circuit that helps the design.

The overall goal of this chapter is to critique the purported business case for corporate social responsibility (CSR) and sustainability, which persists as a major contentious force in convincing companies to become more sustainable. Extant literature on sustainability, CSR and Socially Responsible Investments (SRIs) generally tends to focus on company perspectives decision-making and approaches. This chapter considers an alternative and under-developed perspective and examines CSR from a consumer/public perspective situated in a German context.

This chapter builds a comprehensive literature review and employs a research philosophical point of view underpinned by a social constructionist stance. It examines indicators and attitudes towards sustainability and sustainable consumption together with socially responsible investments and considers whether the buying patterns of German consumers may serve as a rationalisation for a potential business case for CSR and sustainability.

While the awareness of consumers of CSR in Germany towards sustainability tends to be generally relatively prima facie high, it is nevertheless noticeable that German consumers are predominately reluctant to pay a price premium for product possessing a superior sustainability performance. From the alternative lens of SRIs, rather than being a replete and widespread phenomenon, they are still largely a niche market. For these reasons, the potential for the existence of a business case for sustainability, CSR and SRIs tends in reality to be low, in spite of some populist or survey reports and perceptions.

The chapter links a consumer perspective with the business case for CSR. Moreover, it focuses on the German context which tends to be underrepresented in international research.

Persistent change has placed considerable pressure on organizations to keep up or fade into obscurity. Firms that remain viable, or even thrive, are staffed with decision-makers who capably steer organizations toward opportunities and away from threats. Accordingly, leadership development has never been more critical. In this chapter, the authors propose that leader development is an inherently dyadic process initiated to communicate formal and informal expectations. The authors focus on the informal component, in the form of organizational politics, as an element of leadership that is critical to employee and company success. The authors advocate that superiors represent the most salient information source for leader development, especially as it relates to political dynamics embedded in work systems. The authors discuss research associated with our conceptualization of dyadic political leader development (DPLD). Specifically, the authors develop DPLD by exploring its conceptual underpinnings as they relate to sensemaking, identity, and social learning theories. Once established, the authors provide a refined discussion of the construct, illustrating its scholarly mechanisms that better explain leader development processes and outcomes. The authors then expand research in the areas of political skill, political will, political knowledge, and political phronesis by embedding our conceptualization of DPLD into a political leadership model. The authors conclude by discussing methodological issues and avenues of future research stemming from the development of DPLD.

Crowdfunding campaigns reflect the personality traits of the entrepreneur, influencing the chances of a successful fundraising. In this study, the authors focus on three different entrepreneurs’ personality dark traits: narcissism, Machiavellianism and psychopathy. Through a text analysis of 338 equity-crowdfunding campaigns in the UK, the authors identified narcissistic expressions used by entrepreneurs in their pitches, and their impact on funding success. The authors found an inverted U-shape relationship between entrepreneurs’ narcissism and the crowdfunding success. On the other hand, entrepreneurs’ psychopathy has a negative linear relationship with crowdfunding success. This study contributes to the entrepreneurship literature, highlighting the importance of displayed entrepreneurs’ personality traits in engaging with crowd investors.

Interdisciplinary research allows us to broaden our sights and expand our theories. Yet, such research surfaces a number of challenges. We highlight three issues – superficiality, lack of focus, and consilience - and discuss how they can be addressed in interdisciplinary research. In particular, we focus on the implications for interdisciplinary work with paradox scholarship. We explore how these issues can be navigated as scholars bring together different epistemologies, ontologies and methodologies within interdisciplinary research, and illustrate our key points by drawing on extant work in paradox theory and on examples from this double volume. Our paper contributes to paradox scholarship, and to organizational theory more broadly, by offering practices about how to implement interdisciplinary research while also advancing our understanding about available research methods.

Organizational behavior scholars have long recognized the importance of a variety of emotion-related phenomena in everyday work life. Indeed, after three decades, the span of research on emotions in the workplace encompasses a wide variety of affective variables such as emotional climate, emotional labor, emotion regulation, positive and negative affect, empathy, and more recently, specific emotions. Emotions operate in complex ways across multiple levels of analysis (i.e., within-person, between-person, interpersonal, group, and organizational) to exert influence on work behavior and outcomes, but their linkages to human resource management (HRM) policies and practices have not always been explicit or well understood. This chapter offers a review and integration of the bourgeoning research on discrete positive and negative emotions, offering insights about why these emotions are relevant to HRM policies and practices. We review some of the dominant theories that have emerged out of functionalist perspectives on emotions, connecting these to a strategic HRM framework. We then define and describe four discrete positive and negative emotions (fear, pride, guilt, and interest) highlighting how they relate to five HRM practices: (1) selection, (2) training/learning, (3) performance management, (4) incentives/rewards, and (5) employee voice. Following this, we discuss the emotion perception and regulation implications of these and other discrete emotions for leaders and HRM managers. We conclude with some challenges associated with understanding discrete emotions in organizations as well as some opportunities and future directions for improving our appreciation and understanding of the role of discrete emotional experiences in HRM.

Purpose: The evidence regarding the effects of the COVID-19 lockdown on domestic violence is mixed. Studies using hotline call services identify an increase on domestic violence, while studies using police reports find a decrease. One limitation is that most of these studies came from diverse regions using different types of data sources. The purpose of this study is to use two separate data sources to study this question in the same region, and to contribute to the discussion for potential mechanisms that explain this mixed evidence.

Methodology: This study estimates the effects of the COVID-19 lockdown on domestic violence in Mexico City. The authors use two separate data sources: hotline calls and official police reports. Our empirically strategy is based on a difference-in-differences methodology and an event-study design.

Findings: As a consequence of the COVID-19 lockdown, hotline calls for psychological domestic violence increase by 17%, while police reports of domestic violence decrease by 22%. To reconcile these discrepancies between hotline calls and police reports, the authors consider several potential mechanisms. The authors find suggestive evidence that the increase in psychological domestic violence is related to financial stress. Further, the results of this study indicate that the reduction in police reports is related to women facing more barriers to report their abusive intimate partners during the lockdown.

Value: These results confirm that the variation observed in the existing literature is related to the type of data being used. The mixed evidence suggests that more women suffer from psychological domestic violence as captured by hotline calls, while women encounter more barriers to report their abusive husbands to the police as captured by the official police reports.

Purpose – This chapter uses preventive and responsive policing strategies in tandem to develop a multi-level theory that explains the relationship between the police and violence.

Design/methodology/approach – The chapter brings together classical scholarship and more recent sociological research to demonstrate that an effective response to violence is critical in upholding the state’s monopoly on violence and that police officers can reduce violence by preventing it and responding to it.

Findings – Theoretical and practical evidence support the balanced use of responsive and preventive policing strategies to reduce violence. Findings from the literature are used to argue that (1) when law enforcement officers do not effectively respond to violence and/or crime prevention strategies are nonexistent in a community, neighborhood crime is increased and (2) when citizens do not perceive law enforcement officers as legitimate and effective agents of authority, they become more likely to engage in violent offending (Tonry, 1995; Tyler, 2006).

Originality/value – Research has supported the effectiveness of “proactive” (Braga, Papachristos, & Hureau, 2014; Weisburd & Telep, 2014) and “reactive” (Nagin, 2013; Paternoster, 2010) policing strategies in reducing violence, but no research has combined strategies of prevention and response to explain the relationship between the police and violence. The theory proposed in this chapter demonstrates the utility of explaining the instrumental and legitimacy functions of the police across various levels and brings under-protection to the forefront of research on policing and violence.