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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.

The current study aims to investigate the impact of perceived blockchain-related information transparency on consumers’ intention to purchase organic food. This study examines how perceived blockchain- related information transparency, directly and indirectly, affects purchase intentions through attitudes, perceived behavioural control and subjective norms. Additionally, the study explores how blockchain-based trust moderates the influence of perceived blockchain-related information transparency on these factors and the intention to purchase organic food.

Based on the theory of planned behaviour framework and a sample of 5,326 consumers, this study uses partial least squares structural equation modelling to test the research model.

This study finds that perceived blockchain-related information transparency directly enhances consumers’ attitudes towards organic food purchase, perceived behavioural control, subjective norms and intention to purchase organic food. Additionally, perceived blockchain-related information transparency indirectly affects consumers’ intention to buy organic food through three antecedents of the theory of planned behaviour model. Notably, these indirect effects were moderated by consumers’ blockchain-based trust.

This study provides recommendations for leveraging blockchain to enhance transparency and build trust, which could boost consumer engagement and organic food purchases.

This research contributes to blockchain literature by empirically examining the role of perceived blockchain-related transparency and blockchain-based trust in consumers’ purchasing decisions regarding organic food. It provides valuable insights into the consumer-centric benefits of blockchain technology. Furthermore, this study also contributes to the literature on organic food, particularly its promotion through blockchain technology.

While the application of blockchain technology in the organic food supply chain has been increasingly recognized, the extant knowledge of how blockchain-driven traceability influences consumer perceptions and purchase intentions remains underexplored. Grounded in the stimulus-organism-response theory, this study aims to construct a moderated mediation model to examine blockchain-enabled traceability’s direct and indirect impacts on organic food purchase intention through perceived blockchain-related information transparency, considering the moderating role of blockchain-based trust.

A purposive sample of 5,326 Vietnamese consumers was surveyed using the PROCESS macro to test the proposed hypotheses.

The findings indicate that blockchain-enabled traceability significantly enhances perceived blockchain-related information transparency, which positively influences organic food purchase intention. Furthermore, blockchain-based trust was found to positively moderate both the direct effect of transparency on purchase intention and the indirect impact of traceability on purchase intention through transparency.

Practical and managerial insights for stakeholders in the organic food sector are also discussed.

These results contribute to the literature by extending the stimulus-organism-response model to the context of blockchain technology in supply chains and highlighting the critical role of trust in moderating the effectiveness of technological innovations.

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 research applies the stimulus-organism-behavior-consequence framework to explore how blockchain-enabled traceability influences trust in organic food producers and retailers, which impacts consumers’ purchase behaviors and subsequent outcomes.

Using a purposive sample of 5,326 Vietnamese consumers, multiple linear and polynomial regression with response surface analysis were employed to examine the hypotheses.

Blockchain-enabled traceability significantly enhances trust in both producers and retailers, which congruently and incongruently influences organic food purchase behaviors. This behavior also drives consumers’ word-of-mouth and repurchase intentions. Serial mediation analysis confirms blockchain’s impact through trust and purchase behaviors.

Stakeholders should adopt blockchain to boost transparency and trust, which increases consumer engagement. Policymakers can support this transition through regulations and incentives to enhance food security and sustainability.

This study expands on blockchain research by applying the stimulus-organism-behavior-consequence framework in the organic food supply chain, showing how blockchain-enhanced trust synergistically affects consumers’ purchase behaviors, word-of-mouth and repurchase intentions.

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.