Search results

The purpose of this paper is the presentation of an electrical equivalent circuit for inductive components as well as the methodology for electrical parameter extraction by using a 3 D finite element analysis (FEA) tool.

A parameter extraction based on energies has been modified for three dimensions. Some simplifications are needed in a real model to make the 3 D finite element method (FEM) analysis operative for design engineers. Material properties for the components are modified at the pre-modeling step and a corrector factor is used at the post-modeling step to achieve the desired accuracy.

The current hardware computational limitations do not allow the 3 D FEA for every magnetic component, and due to the component asymmetries, the 2 D analysis are not precise enough. The application of the new methodology for three dimensions to several actual components has shown its usefulness and accuracy. Details concerning model parameters extration are presented with simulation and measurement results at different operation frequencies from 1 kHz to 1 GHz being the range of switching frequencies used by power electronic converters based on Si, SiC or GaN semiconductors.

This new model includes the high-frequency effects (skin effect, proximity effect, interleaving and core gap) and other effects can be only analyzed in 3 D analysis for non-symmetric components. The electrical parameters like resistance and inductance (self and mutual ones) are frequency-dependent; thus, the model represents the frequency behavior of windings in detail. These parameters determine the efficiency for the inductive component and operation capabilities for the power converters (as in the voltage boost factor), which define their success on the market.

The user can develop 3 D finite element method (FEM)-based analyses with geometrical simplifications, reducing the CPU time and extracting electrical parameters. The corrector factor presented in this paper allows obtaining the electrical parameters when 3D FE simulation would have developed without any geometry simplications. The contribution permits that the simulations do not need a high computational resource, and the simulation times are reduced drastically. Also, the reduced CPU time needed per simulation gives a potential tool to optimize the non-symmetric components with 3 D FEM analysis.

Our study examines how artificial intelligence (AI) can enhance decision-making processes to promote circular economy practices within the utility sector.

A unique case study of Alia Servizi Ambientali Spa, an Italian multi-utility company using AI for waste management, is analyzed using the Gioia method and semi-structured interviews.

Our study discovers the proactive role of the user in waste management processes, the importance of economic incentives to increase the usefulness of the technology and the role of AI in waste management transformation processes (e.g. glass waste).

The present study enhances the circular economy model (transformation, distribution and recovery), uncovering AI’s role in waste management. Finally, we inspire managers with algorithms used for data-driven decisions.

The purpose of this paper is to analyse student performance and perceptions when a flipped classroom setting is used, in comparison with the traditional model.

The inverted learning model or “flipped classroom” is a pedagogical approach that attempts to reverse the traditional teaching and learning process, making the student the protagonist of their own learning, and is characterised by the theoretical contents being taught “outside the classroom”, allowing students to spend more class time carrying out other types of more practical activities that encourage much more active learning, such as enquiry exercises, problem solving, collaborative projects and so on. The study was conducted on a biology course of the Primary Education Bachelor’s Degree during the 2017/2018 academic year (n = 240).

The results revealed that better learning outcomes were achieved by students when the flipped classroom methodology was proposed. It has also been found that student perceptions of the teaching approach were more positive when the flipped model was followed. The flipped classroom methodology also seems to foster student participation and motivation more effectively than traditional teaching formats, mainly because the active learning activities that are carried out in this new educative approach manage to involve the students in their own learning processes.

Despite the enhanced popularity of flipped classroom research in multiple educational contexts and the growing number of studies published in recent years, there is little empirical evidence regarding the effect of the flipped classroom on learning outcomes and satisfaction in pre-service teachers.

The organizations need to use strategic drivers such as market orientation (MO) and knowledge management (KM) for the development of product and process innovations, which can become a major source of sustainable competitive advantage (SCA). However, there is a gap in the use of these precepts, specifically in Brazilian companies. The purpose of this paper is to measure the relationship among MO, KM orientation, innovation (product and process), SCA and organizational performance (OP).

The research was developed through a survey in 1,072 companies from the industrial manufacturing, commerce and services activity sectors. For the analysis of data, the study used the structural equation modeling method.

This study contributes to managerial decisions in the choice of investment in strategic drivers and innovation, to obtain competitive advantages and economic gains. The results highlight that companies that use market information have formal structures to support innovation processes achieving more successful results.

The framework proposed in this research can be used for different industries and segments.

The theoretical value of this paper is the contribution to the literature with the provision of a framework to analyze the strategic drivers, which are antecedents of innovation in different sectors of activity and in different sizes of companies. It is highlighted as managerial contributions, that the study identified evidence that organizations seek a superior OP to the competitor, creating competitive differentials that result in SCA.

Spirituality has long played an important role in conflict and crisis management at both individual and organizational levels, and the interest in spirituality is increasing day by day. Spirituality gives meaning or purpose to one's life and minimizes the potential for conflict, so spirituality has a mitigating role in conflict and crisis processes. In addition, spirituality is thought to foster values such as equality, honesty, compassion, avoidance of harm, respect, peace, justice, forgiveness, sense of duty, reliability, good citizenship, gratitude, optimism, gratitude, love, dedication, and empathy. Therefore, it can be said that employees who have internalized such moral values will definitely reflect them in their actions and discourses in conflict and crisis situations and will achieve successful results. In fact, spirituality drives the behaviors of employees in both crisis management and coping with crisis management. In this context, it can be said that employees with a high level of spirituality can choose the integrative conflict style in conflict situations and can manage conflict positively and thus prevent a crisis from occurring. It is also foreseen that religious spirituality will play a positive role in conflicts and create a peaceful environment in organizations.

The purpose of this paper is to analyze the effect of knowledge complexity, absorptive capacity and weak ties between franchisor and franchisee on standards compliance related to quality and operative procedures.

A franchisee outlets survey was carried out to investigate the effect of knowledge, franchisee and relationships characteristics on franchise systems uniformity. A linear regression analysis was conducted on a sample of franchisees from different franchise chains and sectors of activity operating in Spain. The authors also controlled for transformation type, which represents the kind of activities carried out in the franchisee units, whether just commercial or both transformative and commercial activities.

Partial support was found for the hypothesis. Knowledge complexity and absorptive capacity do not affect uniformity, although weak ties do affect it: the fewer weak ties, the greater franchise system uniformity. These results allow the authors to identify differences between outlets that carry out commercial and physical transformation activities and those in which only commercial activities are carried out. Specifically, uniformity is greater in outlets that perform both commercial and productive activities, and lower in outlets that only carry out commercial activities.

The paper shows that uniformity can be regarded as a source of competitive advantage in the context of franchise operations with multiple centres dispersed geographically.

Drawing on 61 interviews with Mexican immigrants and ethnographic participant observation conducted over three years, I compare social movement organizing in two cities in one California County: one more progressive and the other more repressive. I profile two campaigns waged by Mexican immigrants and their allies in response to two threats posed by police: (1) car impoundments of undocumented, unlicensed drivers’ vehicles and (2) police killings. As political process theory was extended to authoritarian settings, scholars have demonstrated that both growing political opportunity and threat stimulate mobilization. Building on this trend in the literature, this study’s contribution lies in its specification of the relationship among political opportunities, threat, and mobilization tactics. I argue increasing local political opportunity gives rise to more collaborative protest tactics, while relatively more threatening environments yield more confrontational tactics. Because opportunity and threat are not objectively assessed, nor do they automatically inspire protest, I also consider the role of state targets, formalized SMOs, and the influence of coalition partners on tactics. Ethnographic methods are particularly useful for understanding the way organizers and activists, from within organizations that favor distinct tactical repertoires, perceive and attribute threat and opportunity, shedding light on the micro- and meso-level dynamics that shape the social form of mobilization.

The tax evasion phenomenon affects the economic systems of European countries in different ways. The literature shows that individuals provide biased information both to administrative agencies and household surveys. The effects of tax evasion could thus influence the income inequality computed in official statistics.

In this paper, I investigate whether tax evasion generates a bias when inequality indices are computed using household survey data. To achieve this, I apply a parametric model of the Dagum type (three parameters) on the gross personal income of 27 European countries, distinguishing between the self-employed and employees. Subsequently, the parameters computed in the model are used as dependent variables in seemingly unrelated regressions.

I find that for the self-employed, tax evasion tends to reduce inequality as measured by regular wage statistics. Thus, the results reveal that tax evasion distorts inequality indices, generating an underground inequality.

The purpose of this paper is to present a quantitatively supported explanation of the intellectual development, the schools of thought and the sub-areas of the food cold chain (FCC) research to derive meaningful avenues for future research.

This study builds on bibliometric analysis and network analysis to systematically evaluate a sample of 1,189 FCC articles published over the past 25 years. The descriptive statistics and science mapping approaches using co-citation analysis were performed with VOSviewer software.

The findings reveal a state-of-the-art overview of the top contributing and influential countries, authors, institutions and articles in the area of FCC research. A co-citation analysis, coupled with content analysis of most co-cited articles, uncovered four underlying research streams including: application of RFID technologies; production and operation planning models; postharvest waste, causes of postharvest wastage and perishable inventory ordering polices and models; and critical issues in FCC. Current research streams, clusters and their sub-themes provided meaningful discussions and insights into key areas for future research in FCC.

This study might reshape practitioners’, researchers’ and policy-makers’ views on the multifaceted areas and themes in the FCC research field, to harness FCC’s benefits at both strategic and tactical level. Finally, the research findings offer a roadmap for additional research to yield more practical and modeling insights that are much needed to enrich the field.