Applying calcium fluoride and silica particles: A solution to improve color homogeneity of pc-WLEDS

This article focuses on enhancing the lighting efficiency of pc-WLEDs, a new and advanced lighting solution that has received lots of attention. To adapt to the demand of modern lighting, the lighting performance of pc-WLEDs must be improved, especially the color homogeneity and luminous flux, two of the most important quality indicators of pc-WLEDs. Through experiments, this article proposes using the scattering enhancement particles (SEPs) such as CaF2 and SiO2 with yellow phosphor Y3Al5O12:Ce3+ in pc-WLEDs configuration. The pc-WLEDs model is created by using the LightTools program and set at 8500 K correlated color temperature, while the experimental results yielded from this simulation will be verified by Mie-scattering theory. The information from this article reveals the scattering coefficients of SEPs at 455 nm and 595 nm wavelengths. Moreover, it is confirmed that the employment of CaF2 is effective in promoting the color but may damage the luminous efficiency if the concentration is too high while the SEP material, SiO2, exhibits high luminous efficiency at all concentration

How Digital Natives Learn and Thrive in the Digital Age: Evidence from an Emerging Economy

As a generation of ‘digital natives,’ secondary students who were born from 2002 to 2010 have various approaches to acquiring digital knowledge. Digital literacy and resilience are crucial for them to navigate the digital world as much as the real world; however, these remain under-researched subjects, especially in developing countries. In Vietnam, the education system has put considerable effort into teaching students these skills to promote quality education as part of the United Nations-defined Sustainable Development Goal 4 (SDG4). This issue has proven especially salient amid the COVID−19 pandemic lockdowns, which had obliged most schools to switch to online forms of teaching. This study, which utilizes a dataset of 1061 Vietnamese students taken from the United Nations Educational, Scientific, and Cultural Organization (UNESCO)’s “Digital Kids Asia Pacific (DKAP)” project, employs Bayesian statistics to explore the relationship between the students’ background and their digital abilities. Results show that economic status and parents’ level of education are positively correlated with digital literacy. Students from urban schools have only a slightly higher level of digital literacy than their rural counterparts, suggesting that school location may not be a defining explanatory element in the variation of digital literacy and resilience among Vietnamese students. Students’ digital literacy and, especially resilience, also have associations with their gender. Moreover, as students are digitally literate, they are more likely to be digitally resilient. Following SDG4, i.e., Quality Education, it is advisable for schools, and especially parents, to seriously invest in creating a safe, educational environment to enhance digital literacy among students

Determinants of customer's apartment purchase intention: is the location dominant?

The purpose of this research is to identify and measure the factors affecting the intention to buy apartments of customers in Ho Chi Minh City, Vietnam. The survey carried out with the participation of 200 customers. The authors explore five factors which affect customer's apartment purchase intention include location, features, brand, finance, and subjective norm. The result from Exploratory Factor Analysis (EFA) shows that location, features, finance, and subjective norm have a significant effect on the intention to buy customers' apartments. In which, location in Ho Chi Minh City context is the most influential factor, so, it strongly confirm the research of Adair et al. (1996), Clark et al. (2006), Daly et al. (2003), Kaynak and Stevenson (2007), Opoku and AbdulMuhmin (2010), Sengul et al. (2010), Tu and Goldfinch (1996), Xiao and Tan (2007) and Wang and Li (2006). The study also proposes some recommendations to increase the attractiveness of the apartment. What is more, developers, marketers, real estate policymakers can use the results of this research to understand the needs of customers better and satisfy customers

STEM education and outcomes in Vietnam: Views from the social gap and gender issues

United Nations’ Sustainable Development Goals 4 Quality Education has highlighted major challenges for all nations to ensure inclusive and equitable quality access to education, facilities for children, and young adults. The SDG4 is even more important for developing nations as receiving proper education or vocational training, especially in science and technology, means a foundational step in improving other aspects of their citizens’ lives. However, the extant scientific literature about STEM education still lacks focus on developing countries, even more so in the rural area. Using a dataset of 4967 observations of junior high school students from a rural area in a transition economy, the article employs the Bayesian approach to identify the interaction between gender, socioeconomic status, and students’ STEM academic achievements. The results report gender has little association with STEM academic achievements; however, female students (αa_Sex[2] = 2.83) appear to have achieved better results than their male counterparts (αa_Sex[1] = 2.68). Families with better economic status, parents with a high level of education (βb(EduMot) = 0.07), or non-manual jobs (αa_SexPJ[4] = 3.25) are found to be correlated with better study results. On the contrary, students with zero (βb(OnlyChi) = -0.14) or more than two siblings (βb(NumberofChi) = -0.01) are correlated with lower study results compared to those with only one sibling. These results imply the importance of providing women with opportunities for better education. Policymakers should also consider maintaining family size so the parents can provide their resources to each child equally

Policy Response, Social Media and Science Journalism for the Sustainability of the Public Health System Amid the COVID-19 Outbreak: The Vietnam Lessons

Vietnam, with a geographical proximity and a high volume of trade with China, was the first country to record an outbreak of the new Coronavirus disease (COVID-19), caused by the Severe Acute Respiratory Syndrome Coronavirus 2 or SARS-CoV-2. While the country was expected to have a high risk of transmission, as of April 4, 2020—in comparison to attempts to contain the disease around the world—responses from Vietnam are being seen as prompt and effective in protecting the interests of its citizens, with 239 confirmed cases and no fatalities. This study analyzes the situation in terms of Vietnam’s policy response, social media and science journalism. A self-made web crawl engine was used to scan and collect official media news related to COVID-19 between the beginning of January and April 4, yielding a comprehensive dataset of 14,952 news items. The findings shed light on how Vietnam—despite being under-resourced—has demonstrated political readiness to combat the emerging pandemic since the earliest days. Timely communication on any developments of the outbreak from the government and the media, combined with up-to-date research on the new virus by the Vietnamese science community, have altogether provided reliable sources of information. By emphasizing the need for immediate and genuine cooperation between government, civil society and private individuals, the case study offers valuable lessons for other nations concerning not only the concurrent fight against the COVID-19 pandemic but also the overall responses to a public health crisis

The relationship between brand equity and intention to buy: the case of convenience stores

The research aims to identify the components of brand equity that affect consumer purchasing intentions and measure the effect of brand equity components on the intention of consumer purchases at the convenience stores in Ho Chi Minh City. The authors conduct the group discussions, expert discussion, and then analyze data from 200 valid questionnaires with four components of brand equity, namely perceived quality, brand loyalty, brand association, brand awareness. The results of Exploratory Factor Analysis (EFA) show that all four elements have a positive effect on the customer' intention to purchase in the convenience store of Ho Chi Minh City. In particular, the brand association factor has the strongest influence, followed by perceived quality, brand awareness, and brand loyalty. This research contributes that the results confirm the theory of Aaker (1991), Brown and Stayman (1992), Cobb-Walgren et al. (1995), MacKenzie (1986) in the new context of convenience stores in Ho Chi Minh City, Vietnam. Besides, the study gives some recommendations to help convenience stores improve the elements of brand equity and it, to enhance attraction for consumers

INFLUENCING FACTORS TO LOGISTICS CENTRE FORMATION – A STUDY OF VIETNAM-BASED LOGISTICS SECTOR

Purpose of the study: The paper tries to model dynamic interactions of factors that contribute to the logistics center building. Conducting the desk review and expert consultation, the causality of the factors is systemized in a form of Causal Loop Diagram using the System Dynamics approach. Methodology: System Dynamics (SD) is an approach for studying interlinked behaviors within a system and reflects the interactions of feedback loops. Compared to other approaches, SD demonstrates the real world by using factors and stocks for components and feedback loops for inter-relationships among them. SD model qualitatively illustrates the causal relationship among factors that influence the building of the logistics center. Main Findings: A combination of four different sub-systems, using a questionnaire survey conducted with logistics service users and providers to sort out the high scored factors. Besides, the survey also helps to study the practical conditions and characteristics in showing the demand, the trend, and the development of logistics centers in Vietnam. Applications of this study: Logistics centers (LCs) can be considered as a depot for vehicles where drivers and managers of vehicles are supposed to maintain, repair vehicles, and adjust vehicle operation schedules. Novelty/Originality of this study: As defined by the scope of the project, the SD model provides a qualitative demonstration of the interaction among factors. The built model gives a systematic insight into how factors link to each other

Identification of bacterial intestinal pathogens by a PCR-Reverse dot blot procedure

Intestinal infections which are the important public health concern worldwide, are caused by the bacterial intestinal pathogens. The aim at our study is to develop a simultaneous, rapid, sensitive and specific diagnostic assay by using a combined PCR-Reverse dot blot method for the identification of pathogen strains, including Bacillus cereus, Clostridium botulinum, Clostridium perfringen, Staphylococcus aureus, Listeria monocytogenes, Escherichia coli O157:H7, Salmonella spp., Shigella spp., Vibrio cholerae, Vibrio parahaemolyticus, Yersinia enterocolitica and Brucella spp. Based on the 16S and 23S DNA regions, the two sets of universal primers and twelve specific probes were obtained for amplification and specific detection of those twelve bacterial species. The initial experimental results using bacterial cultures and 50 clinical samples confirmed the in silico hypothesis that was previously established in universal primers and probes design as well as identified with some basic conditions for PCR and Reverse Dot Blot hybridization reactions. Thus, this procedure being further tested for the other kinds of samples such as fecal samples or foods

The Correlation between the Structures of the Nasal Tip on the Ultrasound and the Anthropometry of the Nose in Vietnamese

BACKGROUND: Nowadays, there are few types of research held in Vietnam to investigate the anthropometric index of the nose as well as analysis the structure of nasal tip on ultrasound to identify the relationship between these parameters. AIM: determine the relationship between the height and the width of the nasal tip and the structures constructed these areas by anthropometric and ultrasound measurement. METHODS: a descriptive study in Thanh Van Hospital from December 2017 to April 2019. RESULTS: There were 94 women (62.7%), and 56 men (37.3%) and the average age were 33.6 years old. The height and width of the nasal tip are 10.1 mm and 21.7 mm, respectively. Through the ultrasound, the thickness of the adipose tissues is 3 mm. The width of the interdomal fat pad is 6.5 mm and the distance between two tip point is 5.6 mm. There are the relationships between the distance of two tip points and the width of the tip (r = 0.341), and the width of the interdomal fat pad (r = 0.72). There is also the correlation between the width of the nasal tip with the distance of two tip points (r = 0.46) and the height of the tip with the thickness of the interdomal fat pad (r = 1.23). CONCLUSION: The thickness of the interdomal fat affects the height of the tip, and the distance of two tip points influences the width of the tip