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Despite the wide dissemination and application of current signature analysis (CSA) in general industry, CSA is not commonly used in the wind industry, where the use of vibration signals predominates. Therefore, the purpose of this paper is to review the use of generator CSA (GCSA) in the online fault detection and diagnosis of wind turbines (WTs).

This is a bibliographical investigation in which the use of GCSA for the maintenance of WTs is analyzed. A section is dedicated to each of the main components, including the theoretical foundations on which GCSA is based and the methodology, mathematical models and signal processing techniques used by the proposals that exist on this topic.

The lack of appropriate technology and mathematical models, as well as the difficulty involved in performing actual studies in the field and the lack of research projects, has prevented the expansion of the use of GCSA for fault detection of other WT components. This research area has yet to be explored, and the existing investigations mainly focus on the gearbox and the doubly fed induction generator; however, modern signal treatment and artificial intelligence techniques could offer new opportunities in this field.

Although literature on the use of GCSA for the detection and diagnosis of faults in WTs has been published, these papers address specific applications for each of the WT components, especially gearboxes and generators. For this reason, the main contribution of this study is providing a comprehensive vision for the use of GCSA in the maintenance of WTs.

Electrical machine slots cause an undesirable effect on the m.m.f. wave in the airgap. This effect consists of the occurrence of high frequency harmonics. When the rotor turns, the movement of rotor slots in relation to the stator slots produces cycle variations in the magnetic circuit reluctance. This effect results in high frequency harmonics in the current wave spectrum. Simultaneously high frequency harmonics torques appear. These are known as slot harmonics. To avoid slot harmonics, both in the rotor and in the stator slots, the slots are skewed. When this technique is used, the simplified hypothesis of the finite element model (FEM) in 2D cannot be employed, as it is based on the concept that the magnetic field possesses translational symmetry along the machine shaft. In this paper a method for analysing electrical machines with skewed slots is presented without using the 3D analysis.

The purpose of this paper is to analyze how family ownership influences the strength of the board’s monitoring function in companies’ decisions regarding the assurance of sustainability reports.

The international sample consists of 536 companies operating in more stakeholder-oriented countries during the period 2007-2014. The paper proposes alternative logit models of analysis using the random-effects estimator.

The results provide evidence that a firm’s sustainability assurance and its choice of accounting professionals as higher quality assurers are positively associated with board size and independence. The main result is the positive impact of family businesses on these assurance issues. The paper evidences the greater orientation toward sustainability issues of family businesses. Furthermore, it verifies the greater impact of board size on family firms’ assurance demand.

This study sheds some light on the unexplored topic of sustainability assurance in family firms. One of the differentiating aspects with respect to previous studies is the consideration of the moderating factor of family property. This study also contributes to the understanding of family firms’ demand for assurance and its practitioners, and the literature’s focus on its determinants.

Society in general demands ethical behaviour in the business world. The research aim of the paper is to analyse whether higher education institutions of business contribute to ethical decision-making in students through a specific training approach based on practical methodologies that take into account students' personal characteristics, which may affect ethical decision-making. The acquisition of knowledge should be more effective when it is based on personal characteristics.

Case method, discussion and self-learning methodology were used, and at the end of the term, the students were evaluated and asked to complete a 48 closed-question questionnaire. A linear regression model is performed to analyse to what extent the results are associated to the variables proposed.

The results show that knowledge is an explanatory variable, but personal characteristics such as gender or empathy reinforce the learning. Gender difference affects the ethical decisions made and empathy, showing that training based on emotions is effective. Besides, the results show that students integrate family influence in their training process.

In this paper, the authors have selected empathy, gender and instruction. They have taken into account the incidence of age and family education. In addition, other contextual factors can have an incidence on training and the model could be improved.

The results show that it is necessary to take into account the students' personal characteristics and select an appropriate training methodology to teach ethics and obtain success.

The students graduating from these courses will be future managers and entrepreneurs and will make decisions in which ethical questions must be taken into account, hence the need for training in this respect.

The teaching of business ethics in business faculties is not an easy subject. It is necessary to select the approach of ethic and an effective methodology to achieve the learning objective. This learning methodology must take into account students' characteristics to be effective. The business students are future managers and entrepreneurs who will make decisions in which ethical questions must be considered, hence the need for training in this respect.

In view of the significant deficiencies that have been observed in corporate social responsibility (CSR) reporting practices, some companies have undertaken a new communication strategy based on a combination of the GRI guidelines and the IFC Performance Standards (termed the GRI-IFC strategy). This paper aims to analyse the role of the CSR committee and of assurance services in promoting this novel practice.

The authors use an unbalanced sample of 750 international companies that operate in emerging markets for the years 2011-2016, in which logistic and ordinal regressions are applied to the panel data to test the research hypotheses.

The results show that the existence of a CSR committee facilitates adoption of the GRI-IFC strategy, thus promoting sustainable management policies and systems and enhancing communication with stakeholders. In addition, these specialised committees often commission assurance for sustainability reports, to reinforce strategies aimed at improving corporate transparency.

The analysis of mediation shows that diverse characteristics of corporate governance mechanisms interact in improving sustainability and business transparency.

There is an evident need for greater commitment by institutions to sustainability, for example by requiring greater specialisation of the members of the CSR committee in social and environmental issues. In addition, consideration should be given to including the creation of a CSR committee as a good practice, within the code of corporate governance and to establishing a specific framework for the committee’s actions.

The previously cited impacts of this paper all contribute indirectly to a greater social welfare by generating higher levels of transparency, ethics and corporate performance. Specifically, higher quality verification services will have an impact on the improved functioning of the financial and capital markets, as well as in decision-making by internal and external stakeholders with more reliable information that will favour the implementation of more sustainable processes that in the short and long term will mean more companies who are responsible towards the environment and society.

This novel study explains why companies adopt voluntary strategies in compliance with GRI guidelines, seeking to provide better CSR disclosure.

Corporate digital responsibility is a challenge for companies as it recognizes that the use of technology can have a significant impact on society. In addition, a whole philosophy of nonfinancial disclosure has recently been developing and has become a priority for organizations seeking to be transparent and accountable. While some companies have already adopted this approach, practices related to information transparency in corporate digital responsibility are still in their early stages, creating a need to improve reporting and promote greater understanding in this evolving field. Based on a study analyzing the disclosure of information on digitization and taking into account that the board of directors is the body in charge of companies’ disclosure policy, the study aims to identify the factors that favor this disclosure.

As established by Ponce et al. (2022), IBEX-35 companies are Public Interest Companies subject to European and international regulations and are required to provide information on economic efficiency indicators and nonfinancial indicators. In relation to the proposed objectives, the aim is to analyze the possible factors that condition the degree of dissemination of information on digitization. To this end, a multiple linear regression of the dissemination index has been proposed following the works of Gil et al. (2018), Rodríguez-Ariza et al. (2014) and Briano-Turrent & Rodríguez-Ariza (2013). The estimation will be performed using the SPSS software (version 27).

The results show that the number of independent directors has a positive influence on the level of information disclosed by companies online. Conversely – and in line with previous studies – board size does not have a significant impact on the level of information transparency.

This study has a few limitations that adversely impact the generalizability of the results. First, the subjective problem inherent in the rating and evaluation of information collected in the annual reports of sample companies cannot be excluded. Second, the consideration that each element that constitutes the IDT has the same weight, there being no weighting criteria. Finally, the study population is limited to 35 listed companies, not considering medium and small companies. Nevertheless, despite these limitations, the results are sufficiently interesting to justify and extend the research to a larger number of companies and, of course, to other stock market indices. Another interesting future line of research would be to include more independent variables to analyze what other factors determine the degree of digital transparency of companies.

The study may be useful for organizations to take into account when identifying the corporate governance characteristics that will improve the disclosure of information on digitalization, which is still incipient and voluntary. Similar considerations could be made with respect to the competent authorities in regulating the disclosure of information by companies, insofar as they should promote policies that, in general, favor corporate transparency.

This study contributes to the literature in three main ways: 1) although there is a large body of research that has explored the impact of corporate governance dimensions on the level of nonfinancial transparency, the present study pioneers the approach to digitalization disclosure in Spanish listed companies; 2) it provides evidence that it is highly advisable to have a majority of independent directors to achieve a higher degree of digital disclosure; and 3) the results of this research show the current state of digital transparency on the websites of most of the listed companies in Spain, which could serve as a benchmark for those responsible for issuing corporate governance policies and guidelines.

The purpose of this paper is to examine how active consumers, i.e. consumers that can inter-temporally shift their load, can influence electricity prices. As demonstrated in this paper, inter-temporal load shifting can induce negative electricity prices, a recurring phenomenon on power exchanges.

The paper presents a novel electricity-market model assuming a nodal-pricing, energy-only spot market with active consumers. This study formulates an economic equilibrium problem as a linear program and uses an established six-node case study to compare equilibrium prices of a model with inflexible demand to a model with flexible demand of active consumers.

This study illustrates that temporal coupling of hourly market clearing through load shifting of active consumers can cause negative electricity prices that are not observed in a model with ceteris paribus inflexible demand. In such situations, where compared to the case of inflexible demand more flexibility is available in the system, negative electricity prices signal lower total system costs. These negative prices result from the use of demand flexibility, which, however, cannot be fully exploited due to limited transmission capacities, respectively, loop-flow restrictions.

Literature indicates that negative electricity prices result from lacking flexibility. The results illustrate that active consumers and their additional flexibility can lead to negative electricity prices in temporally coupled markets, which in general contributes to increased system efficiency as well as increased use of renewable energy sources. These findings extend existing research in both the area of energy flexibility and causes for negative electricity prices. Therefore, policymakers should be aware of such (temporal coupling) effects and, e.g. continue to allow negative electricity prices in the future that can serve as investment signals for active consumers.

This study is a targeted review of some of the major changes in European regulation that guided energy policy decisions in the Iberian Peninsula and how they may have aggravated the problem of lack of flexibility. This study aims to assess some of the proposed short-term solutions to address this issue considering the underlying root causes and suggests a different course of action, that in turn, could help alleviate future market strains.

The evolution of the most important (macro) energy and price-related variables in both Portugal and Spain is assessed using market and grid operator data. In addition, the authors present critical viewpoints on some of the most recent EU and national regulation changes (official document analysis).

The Iberian energy policy and regulatory agenda has successfully promoted a rapid adoption of renewables (main goal), although with insufficient diversification of generation technologies. The compulsory closings of thermal plants and an increased tax (mainly carbon) added pressure toward more environmentally friendly thermal power plants. However, inevitably, this curbed the bidding price competitiveness of these producers in an already challenging market framework. Moving forward, decisions must be based on “a bigger picture” that does not neglect system flexibility and security of supply and understands the specificities of the Iberian market and its generation portfolio.

This work provides an original account of unprecedented spikes in energy prices in 2021, specifically in the Iberian electricity market. This acute situation worries consumers, industry and governments. Underlining the instability of the market prices, for the first time, this study discusses how some of the most important regulatory changes, and their perception and absorption by involved parties, contributed to the current environment. In addition, this study stresses that if flexibility is overlooked, the overall purpose of having an affordable and reliable system is at risk.

Spain has one of the greatest photovoltaic potentials in Europe. The boom suffered in the photovoltaic sector during the years 2007 and 2008 led to instability in the electrical system, prompting the legislator to develop a large number of legislative changes trying to control the electric system tariff deficit. These measures profoundly affected plant owners creating a non-transparent secondary market, which are not covered by the current exchange platforms. The purpose of this paper is to analyze the current situation of the photovoltaic market in Spain, try to understand it based on its historical sequence and propose efficiency improvement measures, based on the implementation of best practices and market mechanisms.

This paper studies the legislative evolution in the photovoltaic sector in Spain and its effect on owners and investors. The authors propose an intermediation system that improves the efficiency of the secondary market.

The authors propose an intermediation system that improves the efficiency of the secondary market.

The authors have not found any other paper that proposes the creation of a market for photovoltaic facilities to increase efficiency.

The Spanish lycanthrope arrived successfully to Spanish screens with The Mark of the Wolfman (Eguiluz, 1968), introducing iconic actor and scriptwriter Paul Naschy as werewolf Waldemar Daninsky. This persona would be later developed in more depth in The Werewolf Versus the Vampire Woman (Klimovsky, 1970) and Curse of the Devil (Aured, 1972). Furthermore, Daninsky’s construction responded to the historical repressive context of Francoist Spain, and the strong ideal of masculinity imposed and promoted under the fascist regime (Pulido, 2012).

After a long hiatus in the horror genre, the more recent film Game of Werewolves (Martínez Moreno, 2011) revisits the figure of the Spanish lycanthrope by introducing two different sets of characters embodying two different types of masculinity and, more significantly, by linking the strong, traditional male identity to the myth of the werewolf, paying homage to Waldemar Daninsky.

Thus, through the film’s historically contextualized textual analysis, the chapter seeks to study the myth of the werewolf in twenty-first-century Spain, in relation to the changes in the masculine identity and the historical context to which it refers, exploring the struggle of men to move from the traditional male identity imposed during the dictatorship to a more progressive one.