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In this paper it is proposed a thermal Finite element formulation that accommodates the current density dependency on the resistivity variation with temperature. As an application example, the steady‐state temperature distribution will be produced for a large 3‐phase induction motor as well as the hot spot temperature for different load conditions. The results produced by the proposed Finite element approach will be compared with the solution obtained considering the current density independent of the temperature as well as with experimental data.

In this paper the influence of the neutral in the thermal performance of a three‐phase squirrel cage induction motor fed by asymmetrical supply voltages is studied and analysed. A 2D finite element formulation was used to solve the steady‐state heat transfer problem. The eddy currents in the rotor bars were evaluated using a combined 3D finite element approach with analytical expressions. The numerical solutions are compared with measured experimental results obtained in laboratory tests for two load conditions and two unbalanced power supply situations with and without the neutral wire connected.

The paper aims to estimate the thermal impact of temperature dependency of material characteristics on induction machines, for which a coupled electromagnetic thermal analysis is carried out.

Both electromagnetic and thermal fields are calculated using a weak coupled finite element analysis algorithm. The electromagnetic behavior of the induction motor is obtained by coupling the field equations to the voltage equations of the windings. The nonlinearity due to the saturation of the iron core and the temperature dependency of the electrical conductivity are taken into account. When the heat sources are evaluated the temperature distribution in the induction motor is obtained. In order to improve the accuracy of the formulation, thermal contact resistances, external and internal convection are considered.

The results presented in this paper prove that the temperature dependency of electric material characteristics must be considered, to accurately simulate the behavior of the induction motors during the design stage.

The presented field‐circuit coupling completes the two‐dimensional finite element analysis by introducing the possibility to take into account the three‐dimensional part of the motor (R_tête, L_tête). Another advantage is the ability to include voltage sources. Consequently, a realistic approach for the electromagnetic and thermal behavior of the electrical machine is achieved.

This study aims to measure the degree of innovation of micro and small industrial companies in the West and Southwest metropolitan regions of the city of São Paulo, through a survey with 203 firms in the metallurgy sector.

The research had a quantitative and descriptive focus and used as methodology the validated and international approach known as Innovation Radar.

The degree of innovation in these micro and small companies is low; thus, the authors could not characterize them as systemic innovators. Most of them are little innovative, although some were classified as occasional innovators. The dimensions organization, processes, presence, supply chain and added value were the least developed.

To carry out similar studies in other Brazilian regions, to compare results and draw new conclusions, or even check if the degree of innovation present in micro-firms of these regions would not be even lower; to monitor the evolution of companies through a longitudinal study, to detect improvements in the degree of innovation; and to conduct a qualitative research that can deepen questions on the results of our study, such as the reasons why this type of company does not adopt innovative practices, or even the real suitability of the Innovation Radar model for micro and small enterprises (MSEs). We observed that some dimensions proved to be too sophisticated for these companies, such as R&D investments and the adoption of technological advances.

The study shows that the degree of innovation measured by the Innovation Radar is a useful and initial measure to check an innovative attitude in micro and small companies. It can also drive the actions that should be prioritized to stimulate the culture of innovation in SME. However, it does not allow to answer why this type of organization does not adopt innovative practices as a management attitude. Regarding its contribution, the authors expect that the paper may bring an awareness of managers and owners of micro and small companies for the need to foster innovative practices that can help increase the competitiveness and survival of this type of organization.

In Brazil, despite the fact that MSEs represent 98 per cent of the existing companies, and are mainly responsible for job creation, their leaders have a low concern for innovative practices.

The study contributes to identify the degree of innovation of these firms, which comprise a representative and strategic segment of the city’s economy, by checking to what extent an innovative attitude is effectively present in this sector. The theoretical contribution of this study regards the appropriateness of mechanisms or methodologies created to measure the degree of innovation in large organizations. Dimensions such as technological platform, brand, innovative ambience, degree of organization or systematization of processes, which are frequently considered for companies in general, and especially for large ones, are not sufficient or, instead, too sophisticated to allow an effective measurement of the degree of innovation in MSE. Thus, this study provides information for designing more effective ways to evaluate the degree of innovation that take into account MSE’s specificities, which can be considered innovation efforts, such as simple process improvements, professional development of teams, and actions to seize ideas and opportunities, among others.

This paper aims to analyze the impact of the adoption of ISO 14001 and ISO 9001 on the performance of Portuguese companies. The sample includes the companies listed on Euronext Lisbon, with economic, financial and specific information – the specific being environmental information and quality information – for the period between 2015 and 2019, which corresponds to the post-Troika period when some economic growth started to be witnessed. The specific information of each area is translated into the environmental certification by the ISO 14001 standard, the quality certification by the ISO 9001 standard, and sustainability reports.

To achieve this aim, four variables were used as a measure of the companies' performance, Return on Assets (ROA), Return on Equity (ROE); Tobin's Q and EBITDA Margin. With this data, different panel models were tested to validate if ISO 9001 and ISO 14001 certifications impact Portuguese listed companies performance. Specifically, the authors have used the Generalized Method of Moments, GMM-System, an estimation method proposed by Arellano and Bover (1995) and Blundell and Bond (1998).

The results show that, in general, the environment and quality variables fail to explain the dependent variables, that is, ISO certifications do not provide positive or negative variations in the performance of companies, suggesting that they are not yet as much for civil society, as well as for current or potential shareholders. When used as an independent variable, certification according to the ISO 14001 or 9001 standards, negative and significant oscillations were verified in the dependent variable, MgEBITDA, suggesting that only for managers this variable is determinant, but with a negative impact, given the high costs, it entails without pressure from other stakeholders.

This study is the first to analyze the impact of the adoption of ISO 14001 and ISO 9001 on Portuguese companies' performance. This empirical study aims to show all investors, managers, regulators and civil society itself the long path that still needs to be taken toward sustainability.

This study aims to investigate the bright and dark sides of environmental, social and governance (ESG) during the COVID-19 pandemic, including both the outbreak and recovery periods, for the Chinese hospitality industry.

Using panel data of 564 firm-quarter observations from 2018 to 2020, the authors adopt fixed-effects regression estimation with standard errors clustered at the firm level. To address potential endogeneity concerns, the authors also use the two-stage least squares estimator with instrumental variables.

The results suggest that ESG plays different roles in market- and accounting-based performance during the COVID-19 outbreak and recovery periods. Specifically, ESG practices show a bright side as a reputation builder to mitigate the negative pandemic impact on market-based performance, whereas the dark side of ESG practices consumes firm resources to aggravate the negative pandemic impact on accounting-based performance during the coronavirus outbreak. These results also suggest hospitality companies benefit bountifully from ESG practices during the COVID-19 recovery.

ESG plays a vital role for hospitality firms by providing insurance-like protection during and after the COVID-19 outbreak. Additionally, hospitality firms should evaluate their capability to adapt resource-consuming ESG practices.

Existing hospitality COVID-19 studies have investigated the effect of ESG on firm performance within a short period with mixed results. This study extends the literature by showing the different effects of ESG practices on market- and accounting-based performance during the COVID-19 outbreak and recovery periods.

The purpose of this paper is to inquiry dietary behavior and the physical and mental health status of food pantry users to better understand issues related to food insecurity and to explore predictors of intentions for self-sufficiency.

The authors randomly surveyed 12 food pantries (151 consumers) sponsored by the North Texas Food Bank in USA, regarding dietary behavior, health status, reasons for food pantry use, satisfaction with services provided, and self-sufficient behavior and support.

About 37 percent of survey participants would expect to continue using food pantry services for one or more years. Reasons for food pantry use included low job earnings, unemployment, poor health, and disability. Over 83 percent of them were either overweight or obese, and over half (57 percent) of them had moderate or severe mental disorder symptoms that warrant examination by healthcare practitioners. On average, their health-related quality of life was lower than the general population. Participants’ physical health was significantly correlated with work intention. The hierarchical regression model predicting work intention had a large effect size.

This research has highlighted the importance of improving food pantry consumers’ health and self-sufficiency in order to live sufficiently and healthily.

Community health practitioners need to help food banks address the needs beyond hunger to focus on the larger ramification of food insecurity such as self-sufficiency and health-related quality of life.

This work extends the existing studies focused on food insecurity, and it will enable the collaborations among food banks, social workers, vocational rehabilitation counselors, and public health practitioners.

The purpose of this paper is to present the plan to develop the known algorithm for thermal and electromagnetic coupled problem calculation. This is used for three‐phase induction motor (IM) on nominal load. An additional purpose is verification empiric expressions of the heat transfer and equivalent thermal conductivity coefficients for external faces and air zones in analysed motor taken from literature.

The numerical investigations proposed in this paper are based on 3D finite element models for thermal and electromagnetic fields analysis. Electromagnetic analysis includes iron core losses. It gives additional heat sources to thermal analysis. Heat transfer and equivalent thermal conductivity coefficients are assessed applying empiric expressions. Thermal model is experimentally validated.

The results of calculations and experimental test shows that heat transfer coefficient for external zones taken from literature does not guarantee the equal accuracy of the distribution of the temperature in all volume of the machine.

Taken from literature, empirical equations do not give correct values of heat transfer coefficient. It states ways to go further in the evaluation of heat transfer coefficients.

This paper presents modelling methodology of 3D transient thermal field coupled with electromagnetic field applied in three‐phase IM at rated load conditions.