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The purpose of the paper is to investigate pole face heating in large, salient pole generators and establish a modelling procedure for accurate rotor pole heat loss computation using finite element analysis.

Finite element‐based simulations of the dynamic electromagnetic problem in an idealized 60 Hz, six‐pole, three‐phase generator were carried out, including coupling to three‐dimensional finite element thermal analysis.

The effect of trailing pole face heating was effectively demonstrated. Accurate estimates of the ventilation and convective cooling were shown to be particularly important.

Accurate heat transfer values could only be obtained using a very sophisticated model in a computational fluid dynamics analysis software package. The complexity of the stator end winding alone makes this a daunting challenge, without the inclusion of the rotation effects and stator cooling ducts. At this stage, it was deemed more useful to use the thermal analysis to observe trends.

Three‐dimensional effects are significant and require modelling. However, obtaining steady state behaviour using a 3D analysis is probably not viable yet. The synchronous operating conditions were obtained from a two‐dimensional analysis and used as the initial conditions for a full 3D analysis.

The paper has helped to enhance the understanding of pole face heat loss in large salient pole synchronous generators, fully examining the mechanisms causing the heating. A complete procedure to achieve this task in a realistic time frame using sophisticated finite element analysis tools has been proposed.

The purpose of this paper is to promote practical methods for the numerical modelling of hard magnetic materials and soft ferromagnetic materials in an engineering context (design of electrical machines).

Objectives achieved by the use of a practical, semi‐empirical material model that needs modest material data and computer resources. Methods: a focused theoretical specification and algorithm development; use of actual material data for algorithm validation; incorporation in commercial engineering software as a test harness. Approach: a practical engineering scheme using a macroscopic material model based on readily available materials data. Scope: numerical model of hard magnetic and soft ferromagnetic materials; scalar and vector hysteresis, major and minor loops.

The limited practicality of much of the literature, especially vector hysteresis; successful use of the model in an existing non‐linear numerical solver; energy conservation gives confidence in the results; the electric motor provides a good validation test case.

Possible future research: application to more complicated material properties such as magneto‐relaxation.

The paper extends the scope of computer‐aided engineering design of electrical machines. The impact on the developer: increased sale of an engineering software product. The impact on the design engineer: more efficient designs, reduced prototyping, reduced technical risk.

The algorithm that provides an effective material model; the focus on the practical issues of data and computational resources; the implementation of a theoretical construct in a large‐scale engineering design program. The value is to designers of electrical machines.

Energy policy and sector developments in Greece in the last decades reveal the government and investors' intentions to exploit the energy resources and production potential of the country. Developments regard renewable and hydrocarbon energy sources. Agreements with international companies come with economic terms attached and the prospect of related sectors' development, employment generation, research and innovation. Developments, particularly those related to hydrocarbons exploration, take place in times of climate change mitigation and adaptation and actions to ensure environmentally, socially, and economically sustainable development in line with the goals set out in the United Nations Agenda for 2030 and the European Green Deal. Given these challenges, the design and implementation of timely policies that can promote local supply capacity appear to be of primary importance. This chapter discusses the challenges and opportunities of designing and implementing local content policies with the intention to derive useful policy considerations. The discussion draws from the latest developments with hydrocarbons exploration and production activities in Greece and from the recent relevant to local content literature. The analysis concludes that in the face of climate action, rapid technological innovation, and the high capital intensity that characterize the sector, knowledge transfer, and education upgrade emerge as important factors of achieving sustainable growth through local content policies.

This chapter conceptualizes computational methods across three related, yet distinct approaches: (1) Social Simulation, (2) Data Science, and (3) Big Data. Group communication research is then situated and reviewed along these three lines of research. Although some areas have considerable visibility (e.g., network analysis, text mining), some areas are less visible in group communication research (e.g., Social Simulation, Big Data designs). The chapter concludes with suggestions for issues regarding reliability, validity, and ethics.

The purpose of this study is to examine playful practices in the science video composition of a fourth-grader.

With an analytic interest in “chasing the theory of muchness” (Thiel, 2015a) that describes distinctive moments of affective energies in playful learning, the authors explored a child’s video in which a food chain is dramatized.

The authors identified how muchness manifested in/through her compositional play.

The potential of playful composing and dramatizing to support meaning-making across contexts and disciplines is discussed.

The purpose of this study is to find out the influence degree of harmonic current on the generator operating parameters. In practical operation of the salient-pole synchronous generator, the heat generated by eddy current loss may lead to the breaking of damper winding, and the damper winding is a key component for ensuring the reliable operation of generators. Therefore, it is important to study the distribution characteristics and the influence factors of eddy current loss. Taking a 24-MW bulb tubular turbine generator as a reference, the influence factors that affect the eddy current loss of damper winding are analyzed.

A two-dimensional (2-D) electromagnetic field model of the generator is established, and the correctness of the model is verified by comparing simulation results and experiment data. The eddy current losses of damper winding in various conditions are calculated by using the finite element method.

It is identified that the cogging effect, pole shoe magnetic saturation degree, pole arc coefficient and armature reaction are the main factors that affect the eddy current loss of the generator rotor. When the generator is installed with magnetic slot wedges, the distribution characteristic of eddy current loss is obtained through the study of the eddy current density distributions in the damper bars. The variations of eddy current losses with time are gained when the generator has different permeability slot wedges, pole arc coefficients and pole shoe magnetic saturation degrees.

The study of this paper provides a theoretical reference for the design and optimization of bulb tubular turbine generator structure.

The research can help enhance the understanding of eddy current distribution characteristics and influence factors of eddy current loss in bulb tubular turbine generator.

One of the most important phenomena that have been confronted in the field of household finance is the stock market participation puzzle. The puzzle describes the anomaly that the majority of households do not have ownership of stock market products, though empirically stocks give higher expected returns than risk-free assets. The stock market participation rate plays an important role as it has a direct bearing on the equity premium. In this study, the authors aim to investigate how financial literacy and various proxies of social interaction are associated with stock market participation in South Africa.

The study uses probit regression and ordinary least squares using the South African National Income Dynamics survey Wave 5 of 2017 to investigate whether financial literacy and social interaction are significantly associated with stock market participation. The financial literacy index is computed using factor analysis on the responses to the financial literacy questions used in the survey. The authors use three proxies for social interaction, namely membership in a Stokvel, membership in a men's association and membership in a women's association.

The results reveal that an increase in financial literacy increases the odds of respondents participating in the stock market. Among the control variables, age, race and level of education are significantly associated with stock market participation. When it comes to social interaction, it is belonging to a men's association that is significantly associated with stock market participation. The other proxies for social interaction are insignificantly associated with stock market participation.

The study contributes to the extant literature by using a set of proxies for social interaction that have the potential to influence stock market participation which have not been used in a South African context.

Switched reluctance motors are promising candidates for a wide variety of drive applications. The theoretical description of such motors is often reduced to the rather simple, but clear concept of ΨI‐characteristics. In contrast to this, the machine itself is a real electrical machine and must therefore be analysed as is done with conventional machines although the experimental machine is constructed as simple as possible. The paper will first describe some well known basics connected to very short machines and flux. In the next step, the calculation of stray flux quantities aided by 3D‐FEM is discussed and finally a comparison of calculation and experimental measurements is given.

This paper aims to investigate materiality judgement providing insights, critiques and future research paths in light of the open debate on the role of materiality in corporate financial disclosure, highlighting potential connections and implications with sustainability and intellectual capital (IC) reporting.

The research presents an overview of the analysis of financial materiality, including new stimuli from recent studies and regulatory requirements for financial and non-financial reporting. Accordingly, this study used a systematic literature review (SLR) based on a combination of content, text and bibliometric analysis of materiality in accounting research studies, collecting data from the Scopus database as one of the most relevant repositories.

The SLR identified four relevant research trends, concerning: (1) the relevance of materiality principles in corporate disclosure; (2) financial reporting practices and materiality; (3) theories and approaches in defining financial materiality and (4) the existence of quantitative and qualitative thresholds in the materiality judgement.

The results provide theoretical and practical implications when comprehending the development of the concept of financial materiality in financial statements and whether they can be appropriate in reporting IC as well. We identified future research paths.

From a practical perspective, this study is useful for companies implementing financial materiality based on stakeholder engagement and improving their transparency in financial and non-financial reporting practices.

The research investigates if the process for assessing materiality is in line with the expectations of all stakeholders involved in financial and non-financial reporting.

This research is the first to investigate the scientific basis and applicability of the concept of financial materiality to sustainability and IC reporting.

This study aims to examine the relationship between climate change disclosure performance (CCDP) and audit pricing. The moderating effect of corporate governance characteristics on that relationship is also investigated.

Using a sample of top 300 Australian Securities Exchange listed non-financial firms over the period 2008–2019, this study investigates the association between CCDP and audit fees. The findings are robust to a difference-in-difference test thereby alleviating potential endogeneity concerns.

CCDP is found to be significantly positively related to external auditor fees.

The findings show some important implications for firm management, regulators, investors and auditors. This study presents empirical evidence that climate change, as a factor of external risk, influences audit fees.

Firms with governance structures characterized by larger more independent boards, larger audit committees and audit committees with a higher level of independence significantly moderate the relationship between CCDP and audit fees.

Investors’ demand for firm transparency and disclosure of information regarding the risks of climate change, effects and opportunities has increased significantly over the past decade, as these factors could have a significant effect on valuation and investment decisions.

Importantly, stakeholders need to be aware of the costs of climate change, the quantification of climate change impacts and how firms address climate change in their business risk management processes. This study quantifies the impact of CCDP on auditor risk assessments via audit fees.