A Numerical Analysis of Wind Flow in Urban Areas

The high population density in Vietnam create many challenges in its urban development and supply of residential housing. To accommodate the large population, the buildings tend to go vertical and high density to maximize the development ratio in the limited land space and in the conservation of natural geomorphology. The high density of building blocks reduces the permeability for wind penetration. In the extreme case, the housing estate becomes a wind-obstructing structure that could be causing to environmental problems and health hazard due to low level of ventilation follow. So, a better understanding about wind flow in urban areas could help resolve some of the main difficulties that a designer might encounter to improve the geometries of urban areas. Therefore, this article performs the simulation methodology using Computational Fluid Dynamics (CFD) tools in ANSYS FLUENT software to carry out the urban wind environment in the simple planning and design urban areas. The studied parameters were wind velocity 10 m/s in the case of straight wind and in the case of 450-cross wind. CFD is an effective and efficient tool to visualize a flow phenomenon of a particular flow problem. The advanced computational technique could calculate the fluid properties at all points defined within the model domain, providing a complete set of data within the model. However, it is important to highlight that CFD technologies have not been completely reliable as model assumptions are still unavoidable for the present computational technologies to resolve turbulent flows. Understanding the limitations of CFD is crucial to reduce numerical errors and realize possible erroneous data in the model

Research on Aeroelasticity Phenomenon in Aeronautical Engineering

Aeroelasticity phenomena arise when structural deformations induce changes on aerodynamic forces due to airplane structures that are not completely rigid. The additional aerodynamic forces cause an increase in the structural deformations, which leads to greater aerodynamic forces in a feedback process. These interactions may become smaller until reaching a condition of equilibrium or may diverge catastrophically if resonance occurs. Flutter is an instability aeroelasticity phenomenon which is the most difficult to predict. In this chapter, a numerical method and an experimental method were realized to predict aeroelastic response and characteristic parameters of a wing structure. The numerical method was firstly developed based on the interaction between computational fluid dynamic and computational structural dynamic methods using a coupling system, fluid–solid interaction (FSI), in the ANSYS software. Then, an experiment was set up in suitable conditions to study aeroelasticity characteristics with the goal of comparing the numerical results with the experimental results on the same wing structure at low speed. After that, a developed code based on immersed boundary method (IBM) was realized to predict aeroelasticity response and characteristic parameters of the wing structure. AGARD 445.6 wing model was chosen for this developed procedure at high speed. Obtained results were compared to other numerical and experimental results

A multi-microcontroller-based hardware for deploying Tiny machine learning model

The tiny machine learning (TinyML) has been considered to applied on the edge devices where the resource-constrained micro-controller units (MCUs) were used. Finding a good platform to deploy the TinyML effectively is very crucial. The paper aims to propose a multiple micro-controller hardware platform for productively running the TinyML model. The proposed hardware consists of two dual-core MCUs. The first MCU is utilized for acquiring and processing input data, while the second is responsible for executing the trained TinyML network. Two MCUs communicate to each other using the universal asynchronous receiver-transmitter (UART) protocol. The multi-tasking programming technique is mainly applied on the first MCU to optimize the pre-processing new data. A three-phase motors faults classification TinyML model was deployed on the proposed system to evaluate the effectiveness. The experimental results prove that our proposed hardware platform was improved 34.8% the total inference time including pre-processing data of the proposed TinyML model in comparing with single micro-controller hardware platform

Mechanism of Inverse Magnetoresistance in High-TaT_{a} Annealed MnNi/Co/Ag(Cu)/Py Spin Valves

The magnetic transport properties -- magnetoresistive (MR) effects of MnNi/Co/Ag(Cu)/\break Py pinned spin valve structures (SVs) prepared by rf sputtering method and annealed at $T_{a} = 100$°C - 500°C for 30 minutes in high vacuum ($\sim 10^{ - 5}$ torr) are investigated. The received results show a change in the observed MR behaviors from a normal giant magnetoresistance effect to an inverse magnetoresistance effect after annealing at high temperatures, 300°C and 400°C, for these SVs. The origin and mechanism of the IMR behavior are analyzed and discussed. These results will suggest an ability to manufacture SV devices used the IMR effect for enhancing the application capacities for SV-sensor systems

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

Eliciting patients’ health concerns in consulting rooms and wards in Vietnamese public hospitals

This article examines the doctor’s elicitation of the patient’s presenting health concern in two clinical settings in the Vietnamese public hospital system: the consulting room and the ward. The data were taken from 66 audio-recorded consultations. Our analysis shows that the elicitors used by the doctor in the consulting room often communicate a weak epistemic stance towards the patient’s health issue, while those used in the ward tend to signal a strong epistemic stance. In addition, this contrast between the elicitors employed in the consulting room and the ward is evident in our data regardless of whether the consultation is a first visit or a same follow-up (in which the doctor is the same one that treated the patient on their last visit), though the contrast is less clear for different follow-ups (in which the doctor has not treated the patient before). An additional finding is that the clinical setting has some bearing on the use of inappropriate elicitation formats (in which the doctor opens the visit with an elicitor which is more appropriate for another type of visit). The precise way in which each of the consulting room and the ward operates is, of course, a feature of the Vietnamese public hospital system itself. Hence, the overall contrast between the elicitors and elicitation formats used in these two settings illustrates how, on a more general level, the institutional context can have an impact on doctor-patient communication

Academic Anxiety of Vietnamese Secondary School Students as a Reason for Applying Online Learning

Academic anxiety is one of the major problems in student psychology across the world. It applies equally to students of all ages, from elementary school to college and university students. Research shows that learning online is an effective way to defuse feelings of academic anxiety. Elimination of anxiety is clearly visible regardless of age, gender, or prior online learning experience. The study aims to identify academic anxiety as one of the most important reasons for moving to online learning or blended learning in secondary school. The study investigated academic anxiety among secondary school students in Vietnam. After surveying 677 students in classroom learning, the results showed that 13.7% of secondary students suffered from frequent anxiety, and 3.0% of them suffered from very frequent anxiety. Lower anxiety was observed among students actively participated in-class activities, and students with excellent academic performance. These factors can be optimally enhanced through blended and online learning. There were no differences in academic anxiety among male and female students, urban and rural students. There was a moderate correlation between a student's anxiety level and pressure of the school, parental expectations, students' motivation for high performance, and especially, among students who have the melancholic temperament. And the influence of these negative factors can also be optimally reduced with the help of online learning. Regression model could provide useful suggestions for parents, teachers and students in reducing academic anxiety for students, including the use of full or blended online learning

Determinants Influencing Entrepreneurial Intention in Hanoi, Vietnam

This research employed survey data from 204 students between two groups of  economics and technical majors in Hanoi city for assessing the impact levels of determinants on entrepreneurial intention. The results show that a number of determinants including Need for achievement, Self-efficacy, and Instrumental readiness have positive impacts on student’s entrepreneurial intention. Besides, this study is also to create a basis for  comparative students among different economics and technical majors, work exoperience, and gender. These findings are the basis to recommend policies and solutions to promote entrepreneurship movement in Vietnam. Keywords: Entrepreneurial intention, need for achievement, self-efficacy, instrumental readiness. DOI: 10.7176/EJBM/12-15-10 Publication date:May 31st 2020

Factors affecting the creativity of high school students

Creativity is a vital personality quality of each individual. Each person has their potential for creativity, and it can be nurtured and developed in an appropriate and safe environment. The purpose of the study was to find out which factors from schools and students themselves affect creativity as well as the association between creativity and age, gender and giftedness of students, which then a basis to adjust and establish appropriate methods from schools, families, and students themselves to develop elements and their creativity. The study was conducted on 108 high school students in three grades from giftedness and non-giftedness schools. The data was collected through a survey method using a self-constructed questionnaire and drawing creativity test TCT-DP to determine students' creativity levels and personal information. The study's finding, which uses mathematical methods and one-way analysis of variance, reveals that factors affecting elements and creativity level are objective factors including education environment from school; behavior of teachers, and subjective factors including interests, perspectives, and thoughts of students. It was also found that there were no significant differences in the components of creativity and creativity among students in different grades, gender, and groups of giftedness schools

The Vietnamese Version of the Brief Illness Perception Questionnaire and the Beliefs about Medicines Questionnaire:Translation and Cross-cultural Adaptation

OBJECTIVE: To translate and cross-culturally adapt the Brief Illness Perception Questionnaire (BIPQ) and the Beliefs about Medicines Questionnaire (BMQ) into Vietnamese. METHODS: We followed the guideline by Beaton et al. (2000 & 2007). Stage I: two translators (informed and uninformed) translated the questionnaires. Stage II: the translations were synthesized. Stage III: back translation was performed by two translators fluent in both Vietnamese and English but naïve to the outcome measurement. Stage IV: seven experts reached consensus on the pre-final Vietnamese version (BIPQ-V and BMQ-V). Stage V: field test of the questionnaires on 16 twelve-year-old students and 31 Vietnamese patients. In addition, we determined the internal consistency and test-retest reliability of the questionnaires in 34 Vietnamese patients with acute coronary syndrome. RESULTS: All experts agreed that there was semantic, idiomatic, experiential, and conceptual equivalence between the original and pre-final Vietnamese versions of the BIPQ and BMQ. Cronbach's alpha coefficients of the internal consistency were acceptable for the BMQ-V Specific-Necessity (0.64), BMQ-V Specific-Concerns (0.62), and BMQ-V General-Harm (0.60), with the exception of BMQ-V General-Overuse (0.27). Intra-class correlation coefficients of the test-retest reliability was acceptable for the subscales of BMQ-V (range: 0.77-0.86), and BIPQ-V items (range: 0.62-0.85) with the exception of BIPQ-V 1 (0.44, 95% CI -014-0.72) and BIPQ-V 4 (0.57, 95% CI 0.22-0.81). CONCLUSIONS: The Vietnamese version of BIPQ and BMQ are reliable tools to assess illness perceptions and beliefs about medicines of patients with acute coronary syndrome. Psychometric properties of these questionnaires should be tested in different patient populations