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This paper aims to focus on the effect of the operating condition such as the impeller speed on the centrifugal fan performance and flow characteristics. The ability to predict the behavior of the airflow motion in a centrifugal blower is essential for obtaining the topology optimization design.

A physical model of the air blower consisting of these main parts in a blower system: collector, impeller, outlet flange and volute casing, and the appropriate boundary conditions are set up by ANSYS software. Computation fluid dynamics are performed for the numerical analysis. The calculation of blower performance parameters such as total pressure, efficiency and flow rate is based on the Reynolds averaged Navier–Stokes equations and k-εturbulence flow model.

The numerical results show that the change in operating conditions has a significant effect on the blower performance, and the pressure maintained inside the blower is higher for a larger impeller rotational speed.

This work is original and has not yet been submitted to elsewhere or published previously.

Media information is often considered critical to foster pro-environmental consumption behaviours (PECB). However, empirical evidence was inconsistent about the impact of environmental information exposure on the behaviours. Thus, the study aims to clarify that impact by investigating three different types of environmental information. Moreover, the study posited that consumers who hold different environment-related values may be receptive to and influenced differently by these types of information.

Survey data were collected from 259 Gen-Y consumers in urban areas. The data were analysed for measure reliabilities and validities before hypotheses were tested using ordinary least squares (OLS) regressions.

The results revealed that the environmental problem-, action- and effectiveness-related information exposure affects pro-environmental personal norms (PNs) which then influence the behaviours. More importantly, the influences of action-related information and effectiveness-related information on PNs were moderated differently by egoistic values held by consumers.

The study contributes to the literature by highlighting the importance of information-value congruence in designing effective media campaigns.

This paper employed the self-determination theory (SDT) to examine the synergistic impacts of intrinsic, extrinsic and prosocial motivations in promoting sustained pro-environmental consumption behaviors (PECB). To provide evidence for the study’s theoretical framework, the authors focus on the behavior of reducing single-use plastics.

A mall-intercept survey for consumption of single-use plastic products in three big cities of Vietnam (Hanoi, Da Nang and Ho Chi Minh city) was conducted to test the theoretical framework. In total, 468 consumers completed the questionnaires. Data were analyzed with SPSS and AMOS.

Intrinsic and prosocial motivations are found to be significant predictors of sustained PECB. More importantly, beyond the direct effects of intrinsic and prosocial motivations, the authors also found positive interaction effects between intrinsic and extrinsic motivation and between intrinsic and prosocial motivation on encouraging sustained PECB.

This research offers a new insight for encouraging sustained PECB. Different from the extant perspectives which usually deal with initiating PECB, the authors emphasize sustaining the behavior. Moreover, this research examines the interaction effects between intrinsic and extrinsic motivations and between intrinsic and prosocial motivations in sustaining PECB.

This study aims to explore the situations and socio-economic and health-related factors associated with employment of older men and women in Vietnam.

This study used the nationally representative data in 2019 with a sample size of 3,049 older persons (those aged 60 and over). This study applied logistic regression analyses.

This study found that there were significant differences in employment rates between various groups of older men and women in terms of age group, residential place, marital status and educational level. Controlling for age, education, marital status, place of residence and (in) sufficient income for daily living, the results from logistic models indicated that health issues were strongly associated with lower probability to be employed for both genders. In all tests and regression models, that age and health condition were consistently related with lower employment probability of older persons implied an important consideration in raising normal retirement ages for both men and women.

Due to limitation of the cross-sectional data, this research could not explore how health influences older people’s employment overtime.

Findings of this research provide important and adaptive policy insights for Vietnam to take advantage of older workers for economic growth under an aging population.

To the best of the authors’ knowledge, this has been among the first studies exploring the role of health, which was presented by different indicators, determining employment of older men and women in Vietnam.

The purpose of this paper is to propose an approach, which is easy to implement, for estimating the thickness of the air layer that may separate metallic parts in some aeronautical assemblies, by using the eddy current method.

Based on an experimental study of the coupling of a magnetic cup core coil sensor with a metallic layered structure (consisting of first metal layer/air layer/second metal layer), which is confirmed by finite element modelling simulations, an inversion technique relying on a polynomial forward model of the coupling is proposed to estimate the air layer thickness. The least squares and the nonnegative least squares algorithms are applied and analysed to obtain the estimation results.

The choice of an appropriate inversion technique to optimize the estimation results is dependent on the signal-to-noise ratio of measured data. The obtained estimation error is smaller than a few percent, for both simulated and experimental data. The proposed approach can be used to estimate both the air layer thickness and the second metal layer thickness simultaneously/separately.

This model-based approach is easy to implement and available to all types of eddy current sensors.

This paper aims to examine the economic efficiency of Vietnamese 172 higher education (HE) institutions within the 2012–2016 inclusive period through the Data Envelopment Analysis (DEA) approach. The authors also compare public and private, multidisciplinary and mono-disciplinary, non-autonomy and autonomy, non-international and international HE Institutions’ efficiency.

This study derived from an unique dataset from the Ministry of Education and Training (MOET) of Vietnam. The data set comprises financial and academic annual reports of higher education institutions (HEIs). The authors achieved totally 204 Vietnamese HEIs, and the sample for analysis is 172 after the elimination of missing units, accounting for 84.3% entire of Vietnamese HEIs. The authors estimate the efficiency scores relying on these selected inputs and outputs by using the DEA method.

Overall, HEIs in Vietnam decreased their operational efficiency during the 2012–2016. It also seems that public universities operate in the absence of market mechanism so that they tend to be less efficient than their counterparts in private sector. Based on our analysis, the authors observe that the HEIs including the international programmes have higher efficiency scores rather than these without international programmes.

This study contributes to the theoretical aspects as follows. First, it enriches the existent efficiency literature on HE using the DEA approach. This stands out among similar studies in Vietnam in terms of duration (from 2012–2016) and data size (172 entities). Second, the research is the first to examine HEIs in terms of disciplinary (mono or multi-disciplinary) and autonomy (autonomous and non-autonomous), internalization (international programmes). These aspects have been silent in previous studies of HEIs in Vietnam.

Vietnam's industrial evolution is luring U. S. companies as the country emerges from political banishment.

This study examines the motivational forces of self-transcendence and self-enhancement values in consumers' green apartment purchase intention since the values have been seen as the key determinants of environmental beliefs and concerns that motivate pro-environmental behaviour adoption amongst consumers regardless of external barriers. Additionally, this study identifies the role of environmental content in strengthening the effects of self-transcendence value.

Survey data were collected from 234 residents of three high-rise apartment buildings in Hanoi, Vietnam. Measure reliability and validity were tested by confirmatory factor analysis (CFA) before hierarchical ordinal least squares regression (OLS) was conducted to test the hypotheses.

The research results reveal a significant positive relationship between self-transcendence value and consumers' green apartment purchase intention. However, environmental problem-related content exposure was found to weaken the effect of self-transcendence value on the purchase intention whilst the effect was reported to be strengthened by pro-environmental action-related content exposure.

Theoretically, this study emphasizes the importance of interaction effects between external factors and personal values in explaining consumer's decisions and behaviours. Practically, the research results provide valuable insights for marketers and developers into fostering the adoption of green building apartments amongst consumers.

The purpose of this study was to evaluate how higher tax on tobacco would influence output and employment in Vietnam.

The authors used micro-simulation techniques proposed by Walbeeck (2010). Both national data (from Input–Output Table) and household data (Vietnam Household Living Standard Survey) were utilized.

The results showed that any increase in the excise tax for tobacco would have positive net impacts on both national output and employment. The tobacco industry would not be significantly affected due to its small contribution to national economy and employment. More importantly, money released from reduced tobacco consumption would be reallocated to other goods and services, and thus outputs and jobs in nontobacco sectors would increase.

The key limitation of this study was due to unavailability of updated data, especially Input–Output Table as well as household living standard survey.

This study concluded that government should increase tax on cigarette along with a well-planned roadmap to avoid unexpected consequences on income and employment of laborers in this sector.

This study replicated a popular approach in order to verify an important government policy (i.e. effect of tax on tobacco on output and employment) under Vietnamese context.