Rice husk, in large quantities, is released to the environment due to rice production in Vietnam. If this material can be utilized, it can solve not only the economic issues but also the environmental problems and sustainable development of the country. Laboratory evaluation of asphalt mixture using Nano silica made from rice husk to improve rutting resistance of asphalt mixtures was presented in this study. A 60/70 bitumen was used as control asphalt binder. The ratio of Nano SIO2 used in this study was 0.3%, 0,6%, 0,9%, 1,2%, and 1,5% by weight of powder. A dense gradation with nominal maximum aggregate size of 12.5mm was used for the asphalt mixtures. Marshall stability (MS) test and wheel tracking (WT) test were conducted to evaluate the rutting resistance of asphalt mixtures. It was found that the asphalt mixtures using 0.5%, 1.0%, and 1.5% Nano SIO2 have the rut depths of 5.35mm, 5.39mm, and 5.45mm, respectively, which is 30%, 31% and 29% lower than the control asphalt mixtures at 15,000 load cycles. Moreover, the static modulus of asphalt mixtures using 0.9% Nano SIO2 at 60oC is higher than the control mixtures. Based on the results of this study, it can be concluded that the addition of Nano SIO2 into asphalt mixtures can enhance the rutting performance of asphalt concrete under high temperatures significantly. It is noted that these conclusions were based on only on a limited number of samples and conditions. Further studies must be conducted to investigate the effect of Nano SIO2 on fatigue cracking and moisture damage of asphalt pavement in the field.

Sustainable development – including tourism development – is the general trend of all economies. With the orientation to build and develop the tourism industry into a key economic sector and become a tourist center of the Southeast region, Vietnam, Ba Ria-Vung Tau Province is demanding a proper, rational, development policy, while ensuring the development and exploitation of immediate natural advantages, and ensuring long-term sustainable development. The objective of this study is to examine the factors and their trends in sustainable tourism development in Ba Ria-Vung Tau Province, Vietnam. Methods used include descriptive statistical analysis, exploratory factor analysis and regression analysis. Data was collected from the results of a survey of 550 domestic and foreign tourists visiting Ba Ria-Vung Tau. With the help of SPSS statistical software, 12 groups of factors affecting sustainable development were identified including: economy, society, environment, humanistic tourism resources, natural tourism resources, tourism human resources, tourism products and service, tourism quality, infrastructure, technical facilities, governmental management and group of criteria to evaluate sustainable tourism development. The research results show that there are four groups of factors that significantly affect sustainable tourism development in Ba Ria-Vung Tau. These are groups of factors: Society, Environment, Tourism products and service, and Technical facilities.

The purpose of this study was to examine the effect of two-dimensional factor of motivators and hygiene on civil servants’ job satisfaction using the partial least square structural equation modeling (PLS-SEM) as a technique employed to analyze the measurement and structural models. Exploratory study was deployed to evaluate the relationship among variables. By using multistage stratified sampling, statistical data was collected from a survey of 441 public municipal civil servants who have employed in various levels (municipal government, districts and communes) in Vietnam. The findings provided evidence that hygiene factors (relationship with leader, salary, relationship with coworker and working environment) directly impact on civil servants’ job satisfaction. Meanwhile, only career development factor from motivators significantly influenced on public employee’s job satisfaction. Based on the empirical results, the hygiene factors of job satisfaction are more dominated that the motivators one. This finding suggests that municipal governments should focus policies on improving the hygiene factors which lead to higher job satisfaction on civil servants. Gaining a thorough understanding of the determinants of job satisfaction toward municipal public servants will enable policy makers to grasp the factors that results in retaining employees. Finally, the policy makers can use this knowledge to promote civil servants’ job satisfaction.