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Static converters generate current harmonics in power grids. For numerous studies, analytical frequency modeling is preferred to carry out their harmonic modeling in the context of sizing by optimization. However, a design by optimization has to consider other constraints, e.g. modeling constraints and operating constraints. In this way, this paper aims to focus on applying an analytical frequency modeling on the sizing by optimization of an aircraft electrical power channel.

The paper aims to size a multiphysical system by optimization. In this way, the sizing of an aircraft electrical power channel by optimization has been carried out. The models of all the channel components are analytical. Specifically, the frequency model of the power electronics is based on Tran et al. (2016) and is made of equalities and inequalities. Due to this modeling choice, the optimization satisfies hundreds of constraints, such as modeling constraints and static converter operating constraints. Furthermore, transient constraints are only verified after optimization.

The difficulty is the modeling of the system by taking into account nonlinear implicit equations having several solutions. A solution is the addition of inequality constraints to the model to guide the implicit solving. Furthermore, this greatly helps the optimization algorithm to find the good operating mode of the static converter, at steady state. This aspect is indispensable to validate the sizing model.

The number of the configurations per operating period of the static converters is defined a priori and limited.

The analytical model for the sizing is formulated as a constrained optimization problem. Its solving and the sizing by optimization are carried out by the same optimization algorithm.

An analytical approach is preferred to carry out the harmonic modelling of power electronics converters because it is generally faster than time simulation chained with FFT. However, the difficulty of such an approach is to build the model and to manage the uncontrolled commutations that occur in the studied static converter, and also to deal with large equations. The purpose of this paper is to propose an aid in the frequency modelling of the drive elements, in the frequency domain, including all key parameters for sizing aim i.e. a way to optimize the EMC filter using different algorithms.

The paper aims to propose an aid to create such models, and to assure its good solving, i.e. that the correct operating mode is represented. So, the solving problem is formulated as an optimization problem under constraints, to solve this difficulty.

The difficulty is to be sure to deal with the good operating mode of the static converter when soft or uncontrolled commutations occur. So, the model is formulated as a constrained optimization problem. The paper proposes a symbolic approach, that allows to build automatically the frequency model. It is translated to be solved in Matlab.

The approach does not fit for static converters with a control implying numerous commutations per operating period. However, the approach deals with natural and soft commutations.

The modelling is based on the use of linear components and ideal switches.

The purpose of this paper is to describe an optimization methodology based on a mixed (analytical‐numerical) design model and evolutionary algorithms.

In this paper, optimal sizing is used to design the new architecture of an embedded electrical system. An approach is presented for defining the specifications and a method for modeling an embedded electrical network. This will enable the optimization problem to be set.

This paper shows that the proposed methodology is useful for sizing an embedded electrical system. It is illustrated by its application to the sizing of an aircraft electrical power channel (auto‐transformer‐rectifier unit type).

An original approach is proposed for limiting the search space before using the evolutionary algorithms. The advantage of this approach is to increase convergence speed of the evolutionary algorithms.

Service quality has been widely recognized as the core value of any higher education institution (HEIs), especially in the context of higher education reform in Vietnam. The paper aims to assess the student’s perceived service quality using SERVPERF scale and to find the relations between perceived service quality, satisfaction and loyalty in one public university in Vietnam.

The self-structured questionnaire using SERVPERF scale was administered to 350 students currently attending full-time courses at the university. Confirmatory factor analysis was used to certify the elementary factors. The regression models were applied to determine the relationship between service quality, student satisfaction and student loyalty.

The findings revealed the significant relationships between student perceived service quality with satisfaction and loyalty. However, this relationship is mediated by student satisfaction.

The study is limited to public university education service and examined the perspective of student as “primary customer”; therefore, generalizing the results to other service industries and other role of student as stakeholder or citizen should be used with caution.

The SERVPERF scale could be delivered regularly to get the student’s perception on the HEIs performance. The results should be taken for purpose of continuing quality improvement to enhance the satisfaction and loyalty, particularly in the context of highly competitive environment and university autonomous in Vietnam.

This is believed to be the first study in Vietnam with sufficient evidence to support the concept that service quality positively related to students’ satisfaction and loyalty and satisfaction as mediating factor.

This chapter provides information on the development of Vietnamese education under the influence of global forces based on the analysis of relevant education research and policies using Wolhuter’s frameworks. In the process of coming up with ways to develop education in the face of different influences of globalization, besides having reactions with patterns commonly found in countries around the world, Vietnam also has responses that reflect its own political, sociocultural and economic characteristics. The state still plays a controlling role in education at all levels and many culture-related features that have existed throughout the country’s history have hardly changed, namely aspects related to teachers, learners and teaching and learning methods. To sustain its education in the globalized era, Vietnam must make more efforts in various aspects such as the link between education and employment, the logic of education objectives, the feasibility and appropriateness of curricula, quality of education, especially of higher education and equality in education for underprivileged groups.

This study examines the evidence of the impact of climate change on the financial performance of basic materials companies in Vietnam.

The research sample includes eighty-two basic materials companies listed on the Vietnamese stock market from 2003 to 2022. This study used one-way and two-way fixed-effects feasible generalized least squares (FGLS) estimation methods.

Climate change, measured through variables including changes in temperature, average rainfall, greenhouse gas emissions and rising sea levels, has a negative impact on the financial performance of companies in this industry. The study also found that, with rising temperatures, the financial performance of steel manufacturing companies decreased less than that of coal mining and forestry companies, but increasing greenhouse gases and rising sea levels reduced the financial performance of steel companies. We did not find evidence of any difference in the impact of climate change on the financial performance of basic materials companies before and after the UN Climate Change Conference (COP 21). This is a new finding, which is consistent with empirical studies in Vietnam and different from previous studies in that it provides new evidence on the impact of climate change on the financial performance of basic materials companies in the Vietnamese market and cross-checks the impact of climate change by sector and over time.

To the best of our knowledge, this is one of the first articles on climate change and the financial performance of basic materials companies.

This study aims to investigate the association between corporate governance (CG) and the corporate social responsibility (CSR) information disclosure as well as the moderating role of state-ownership between CG and CSR disclosure.

To examine the relationship between CG and CSR disclosure, this study used the feasible general least squares and generalized method of moments method on a sample of 165 non-financial quoted companies over the 2015–2018 period, which account for about three-fourths of the Vietnamese stock exchange.

The findings suggest that enterprises with smaller board size consisting mainly of independent directors have a higher CSR disclosure level. Moreover, when the chief executive officer is concurrently the chairman of the board, the level of CSR disclosure falls. Additionally, the moderating role of state ownership enhances CSR disclosure.

The empirical results of this study form a solid foundation for policymakers and other stakeholders’ decisions in investing or establishing policies.

This study provides empirical evidence on the relationship between CG and CSR disclosure in Vietnam – a developing country with no legal requirement on CSR disclosure. Moreover, this study emphasizes the moderating role of state ownership between CG and CSR disclosure, which clarifies the role of state ownership in establishing CG mechanisms.

This study aims to examine the relationship between corporate social responsibility (CSR) and firm value (FV) with the moderating role of the organizational life cycle (OLC).

To fill the missing link of the CSR–FV relationship in the life cycle of the firms, this study divided the firm life cycle into five stages and tested the impact of FV on CSR in each phase. This study uses the ordinary least squares, generalized method of moments method with the dynamic panel data model of 225 Vietnamese listed companies for the period from 2014 to 2018.

This study’s findings confirm the positive effect of CSR on FV. Besides, in most of the stages of the firm life cycle, FV positively affects CSR practices, and this effect is highest in the growth stage. In the decline phase, the relationship between FV and CSR is complex depending on the resources and ability of companies. This study’s results are trusted through many robustness tests.

This research does not include all financial, insurance and investment firms to measure the CSR–FV relationship with OLC as moderating role. Further research might conduct in the larger sample or using data in cross countries enhance the evidence for the given relationship.

This research contributes empirical evidence to the scientific literature on CSR, FV and OLC, which would be tremendously helpful for policymakers and business owners to enhance company efficiency.

Management practices and competition levels have been shown as important factors affecting the performance of enterprises that do not include banks. The paper, thus, aims to measure management practices and to study the effect of management quality and competition level on the performances of the first-level branch of commercial banks in the context of the Viet Nam banking system.

The study employed the approach of Bloom and Van Reneen (2007) to quantify management practices of the commercial banks. The level of competition was measured by the number of competitors suggested by Nickell (1996) and the index suggested by Boone (2008). Finally, the effects of management practices and competition level on the bank performances were jointly estimated through a Cobb–Douglas production function, similar to the one used by Bloom et al. (2014).

The results show that the management practices score is, on average, above the average. While the management practices are found to positively correlate with profits, the competition level is found to significantly reduce bank profits.

Cross-sectional data limit the findings of the paper to a point of time. In the future, studies with panel data are desirable.

The findings of the study help bank managers to make more informed decisions about management practices. Any policy promoting new entrants to the banking market should be carefully considered.

The paper is the first to measure the management practices of commercial banks and to explore the impacts of management quality and competition level on bank performances.

This study aims to examine the impact of managerial use of motivating language on employee absenteeism, turnover intention, job satisfaction and job performance for employees from three nations: India, the USA and Vietnam.

Data is collected from 614 employees working in India, the USA and Vietnam. A variance-based partial least squares structural equation modeling technique is used to test the hypotheses. In addition, a statistical test is used to examine the statistical differences in the results across the three nations.

The findings are consistent with the motivating language theory, in that managerial use of motivating language can be an effective strategy in motivating employees. Specifically, motivating language is found to significantly decrease employee absenteeism and turnover intention, as well as significantly increase job satisfaction and performance across the three nations. The effect sizes indicate that, across all samples, motivating language has a medium effect for all employee outcomes, except absenteeism, which is shown to have a small effect size. Moreover, the results indicate that employees in different cultures perceive and interpret the leader’s use of motivating language in different ways. Whereas motivating language may receive greater success in promoting workers’ job performance in eastern cultures, it is also more effective in retaining employees in western cultures.

The study adds to the literature in three major ways. First, it provides evidence for two understudied relationships: motivating language and absenteeism and motivating language and turnover intention. Second, it assesses the generalizability of the motivating language theory by investigating data from India, the USA and Vietnam. Finally, this paper offers a statistical comparison of the three samples to analyze how the relationship between motivating language and worker outcomes differ among the three samples.