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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.

This work aims to demonstrate the use of electrochemical chloride extraction (ECE) to remove chloride ions away from the steel rebar in chloride-contaminated mortar and to mitigate the corrosion of the embedded steel.

To simulate salt contamination in concrete, sodium chloride was added at 0.5 per cent by weight of cement in the fresh mortar featuring a water-to-cement ratio of 0.45. The ECE treatments were varied at two electrical current densities (1 and 5 A/m²), using two electrolytes (0.1M NaOH and 0.1M Na₃BO₃ solutions) and for two periods (2 and 4 weeks). The average free chloride concentration in cement mortars before and after ECE treatment was quantified using a customized chloride sensor, whereas the spatial distribution of relevant elements was obtained using energy-dispersive X-ray spectroscopy. The effect of ECE treatment on the electric resistivity of mortar and the corrosion resistance of steel rebar was investigated by electrochemical impedance spectroscopy and potentiodynamic polarization measurements, respectively.

The experimental results reveal that the ECE treatment was effective in removing chlorides and in improving electric resistivity and compressive strength of the mortar, when using the sodium borate solution as the electrolyte. In this case, a 4-week ECE treatment at 1 A/m² decreased the free chloride content in the mortar by 70 per cent, significantly increased the Ca/Si ratio in the mortar near rebar, led to a more refined and less permeable microstructure of the mortar and significantly improved its compressive strength. The ECE treatment was able to halt the chloride-induced corrosion of steel rebar by passivation. A 4-week ECE treatment at 1 A/m² using sodium hydroxide and sodium borate solutions decreased the corrosion rate of rebar by 36 and 34 per cent, respectively.

This electrochemical rehabilitation of steel-reinforced concrete under chloride-contaminated condition is very effective in prolonging its service life.

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.

This study aims to examine interactions between multiple management accounting routines in integrating a new management accounting routine into a routine cluster.

This study uses a theoretical framework based on routine clusters, including routine complementarities. The authors use an in-depth case study to explore interactions of a management accounting routine integrating into a routine cluster.

The findings show that complementarity between an existing and a new management accounting routine facilitates integration of the new routine into a routine cluster. They also suggest that when an ostensive understanding of a routine exists, the integration of the new management accounting routine is stronger, as the new and existing routines in the routine cluster are more closely intertwined.

To the best of the authors’ knowledge, this paper is among the first to explore the role of intertwinedness of a new management accounting routine and existing organizational routines in integrating a new management accounting routine into a routine cluster. The findings imply that future management accounting research may need to distinguish between different forms of complementarity.

This study aims to investigate the moderating role of sociodemographic factors, specifically age and education level, in the knowledge-attitude-behavior (KAB) model concerning information security awareness (ISA) amid growing technological threats.

This study uses a survey methodology, collecting data from 400 working individuals in Vietnam, to test the applicability of the KAB model and evaluate the moderating effects of age and education on the model’s established relationships. In addition, the theoretical model and hypotheses were evaluated using the partial least squares structural equation model (PLS-SEM) approach.

This research confirms the relationships posited in the KAB model. Notably, it shows that younger employees showcase a more positive attitude and behavior toward information security compared with their older counterparts. In addition, higher education levels strengthen the positive association between information security knowledge and attitude. The findings underscore the imperative for organizations to consider sociodemographic variables when formulating strategies to enhance ISA.

This study extends the KAB model by exploring the impact of sociodemographic factors, focusing on age and education in ISA. Overcoming the oversight in current literature, particularly in the context of technological threats, the research uses PLS-SEM and targets a specific demographic in Vietnam.

“The world needs science, science needs women” is the message given by UNESCO in the program for the development of women in science” (UNESCO, 2017). In Vietnam, women’s participation and achievements in scientific research is considered a great and important resource for industrialization and modernization. Even so, are there gender differences in scientific achievement in the social science research institutes in Vietnam? What factors influence the scientific achievement of female social researchers? The answers will be based on data from a 2017 survey with a sample of 756 researchers, of which 77.6% were female. The survey was conducted by the Vietnam Academy of Social Sciences, a leading, ministry-level national center for the social sciences in Vietnam. This chapter analyzed the scientific achievements of researchers through their position as principal investigators of research projects and their publications, and factors that may impact this. Bivariate and multivariate analyses of factors that may affect the scientific achievement of researchers found that gender differences in academic achievement in the social sciences in Vietnam was still prevalent. Female researchers’ scientific achievements were lower than those of their male counterparts. The contribution to science of Vietnamese female researchers was limited by many different factors; the most important were the academic rank of the researchers and gender stereotype that considered housework the responsibility of women.

This study aims to examine the accessibility, loan purposes and effects of informal credits on poor households in Northern mountainous Vietnam.

This study used primary data collected directly from surveying 402 poor households in Thai Nguyen province using a well-designed questionnaire. The probit model is employed to specify which factors affect access to informal credit, the tobit model is used to estimate the borrowing functions specified. In addition, descriptive statistical analysis is also used to describe the accessibility, purposes and effects of informal credit on poor households.

The results show that there is a considerably high proportion of informal borrowings from relatives, neighboring villagers, professional moneylenders, rotating saving and credit groups, trade credits and mortgages. Labor force ratio, social capital and residential land areas are the key determinants of poor households' informal borrowings. The purposes of borrowing are diverse. The informal loans also have certain significant effects on poverty reduction and the welfare of poor households.

The effects of the informal loans on house welfare should be quantitatively evaluated.

The findings from these analyses allow us to draw relevant policy implications for the development of rural finance in other low-income, developing countries.

This research contributes to the body of published literature in several ways. Firstly, it provides understanding of the performance of the informal financial subsector. Secondly, the informal subsector of rural finance is evaluated in close relation to the formal subsector.

This paper aims to measure the COVID-19-related disclosure extent of listed firms in Vietnam and its associated factors.

The authors apply a previously developed reporting framework to evaluate the disclosures of 100 listed firms with the largest market capitalization on the Hanoi and Ho Chi Minh stock exchanges as of 31 December 2021. The disclosures were from integrated reports, annual reports, corporate governance reports and financial statements. The authors then used a regression model to examine the factors that influenced the disclosures, such as corporate governance, ownership concentration and firm profiles.

The research results reveal that the extent of COVID-19-related disclosure in Vietnam is relatively low. It also finds that the audit committee, firm size, age and industry are positively associated with the extent of COVID-19-related disclosure.

To the best of the authors’ knowledge, this study is the first to examine COVID-19-related disclosures of listed companies in Vietnam and their determinants. It contributes significantly to the empirical evidence in this field. The findings of this study can help corporate managers and policymakers to improve information disclosure practices during future financial crises.

This study aims to investigate whether the extent of corporate disclosure, proxied by COVID-19-related disclosure, affects the dividend policy of listed firms.

The study uses a multinomial logistic regression model to examine the relation between corporate disclosure and the dividend policy of the 100 largest market-cap firms in Vietnam in 2021. The COVID-19 pandemic, with its unique impact on business operations, serves as the backdrop for this analysis.

The findings indicate that firms with more extensive COVID-19-related disclosure are more inclined to distribute dividends in the form of stocks or cash instead of omitting them.

This research contributes to the understanding of how corporate disclosure practices influence a firm’s financial decisions, particularly in the context of the COVID-19 pandemic. The findings hold implications for corporate financial decision-making during times of macroeconomic shock.

The purpose of this paper is to investigate the development of Viet Nam’s approach to higher education quality assurance during the past dozen years since its establishment, focusing on the achievements and challenges.

This is a desktop analysis study. The paper analyses the policies and practices related to the development of Viet Nam’s higher education accreditation system by reviewing associated literature.

The research has found out that there are several achievements, including: the development of the accreditation framework; establishment of accrediting agencies; completion of almost universities’ self-assessment reports; implementation of external assessment exercise at some institutions, a few of which were awarded accreditation certificates. However, there remain a number of challenges related to the independence of the accrediting agencies, human resources, accreditation standards and criteria, institutions’ awareness about accreditation and the pace of accreditation implementation.

The primary limitation of this study is the research methodology which merely relies on document analysis. It would be more credible if the findings could be triangulated with data taken from other sources such as interviews with key stakeholders.

On the basis of the analysis of achievements and challenges at both macro and micro levels, discussion and recommendations are made for future policy-making and management in the field of higher education accreditation.