小規模バイオガス発生装置を用いたベトナム中部の持続的な農村開発のための畜産・食品廃棄物利用に関する環境面・経済面の評価

Livestock waste and food waste are the two main sources of solid waste in Vietnam. Small-scale biogas digesters have been promoted to use in farm households in part of central Vietnam, but the actual conditions of the biogas digester operation and the size of environmental and economic benefits have not been well documented. This study aimed to assess the environmental, economic, and social benefits of using biogas digesters in central Vietnam and provide recommendations to increase the benefits from using biogas digester.北九州市立大

THE FACTORS IMPACT ON THE TRAVEL INTENTION OF HANOI'S PEOPLE AFTER COVID-19 PANDEMIC

The article studies the factors that affect the intention to travel after the Covid-19 pandemic of Hanoi citizens. The research team uses a model of factors that affects the travel intention of people in Hanoi city after the Covid-19 pandemic, including (1) Attitude, (2) Social influence, (3) Image of Destination, (4) Risk perception, (5) Trip expenses, (6) Propulsion. With 303 participants in the survey, the research results show that the factor "The influence of propulsion" had the largest average score (3.99), indicating that the motivation of desire to relax and explore are vital factors that affect the travel intention of Hanoi people after the Covid-19 epidemic. The factor "Effect of perception of risk" has the lowest score (3.56) but shows some concerns such as weather forecasting, trip expenses' estimation, transportation problems, inadequate information, epidemic prevention, and food safety issues, which will not hinder people's intention to travel. That partly shows that Vietnam's tourism industry has been invested, cared for, and is on the way to development in recent years. From the research results, within the framework of the article, the research team also proposed some measures to stimulate tourism demand after the Covid-19 pandemic

DEVELOPMENT AND APPLICATION OF THE ENVIRONMENTAL HYDRODYNAMIC 3D MODEL FOR COMPUTATION AND FORECASTING OF OIL POLLUTIONS IN COASTAL MARINE ENVIRONMENT

Joint Research on Environmental Science and Technology for the Eart

SURVEY RESULTS OF THE FACTORS AFFECTTING ORGANIC FOOD PURCHASE INTENTION OF CONSUMERS

The research examines factors that influence the organic food purchase intention of Vietnamese consumers. In accordance with theoretical behavioral models and organic food research, data was collected and analyzed via SMARTPLS. Inspecting results demonstrate that 4 factors have a positive influence on organic food purchase intention. Additionally, the research team evaluates the levels of influence of each factor through descriptive statistics of the factors’ average value. The evaluating results are the foundation to propose remedies that encourage the organic food purchase intention of Vietnamese consumers

Development of PSO for tracking Maximum Power Point of Photovoltaic Systems

For a photovoltaic system, the relationship of the output voltage and power is usually non-linear, so it is essential to equip a MPPT controller in PV systems. Furthermore, the hotspot problem is a common phenomenon, resulting from the PV system operating under PSC. Partial shading not only damages the PV cells, but also makes it difficult to find the global MPP in the characteristic curves of P-V. The paper proposes a novel version of PSO, namely PPSO in order to detect the global peak among the multiple peaks, known as the true maximum energy from PV panel. For this, the PPSO algorithm makes the velocity of each particle be perturbed once the particles are struck into a local minima state in order to find the best optimum solution in the MPPT problem. The perturbation in the velocity vector of each particle not only helps them tracking the MPP accurately under the changing environmental conditions, such as large fluctuations of insolation and temperature like PSC; but also removes the steady-state oscillation. The proposed approach has been tested on a MPPT system, which controls a dc-dc boost converter connected in series with a resistive load. Moreover, the obtained results are compared to those obtained without any MPPT controller to prove the efficiency of the suggested method. In addition, this novel version gives the highest accuracy of tracking the optimum power in the least iteration number as compared to the conventional PSO

Factors affecting the flipped classroom in the educational context of Vietnam

In the context of the implementation of the 2018 General Education Program, teachers are required to implement a teaching model oriented to the development of students’ quality and competence. Teachers are encouraged to adapt the flipped classroom model of teaching in schools as its advantages are suitable for novel teaching strategies. This study focuses on analyzing factors affecting the application of this model in the teaching and learning process by collecting feedback from 351 teachers from various cities in Vietnam. The questionnaire included Likert-type questions analyzed by IBM SPSS Statistics version 20 for quantitative analysis and an open question for qualitative analysis with context and personal information. The research-oriented factors focus on the group of potential internal factors (perception, proficiency, desire and readiness of teachers) and the group of external factors (infrastructure, facilities and support resources, training programs). The results showed that those factors include the school’s infrastructure and information communication technology (ICT) condition, the teacher’s ICT competence as well as competence-related teaching and assessment methodologies and the students’ internet access conditions. Finally, the study offers suggestions on how to apply this model in teaching practice to meet the requirements of educational innovation in Vietnam

An Improved MobileNet for Disease Detection on Tomato Leaves

Tomatoes are widely grown vegetables, and farmers face challenges in caring for them, particularly regarding plant diseases. The MobileNet architecture is renowned for its simplicity and compatibility with mobile devices. This study introduces MobileNet as a deep learning model to enhance disease detection efficiency in tomato plants. The model is evaluated on a dataset of 2,064 tomato leaf images, encompassing early blight, leaf spot, yellow curl, and healthy leaves. Results demonstrate promising accuracy, exceeding 0.980 for disease classification and 0.975 for distinguishing between diseases and healthy cases. Moreover, the proposed model outperforms existing approaches in terms of accuracy and training time for plant leaf disease detection

Scaling up the use of low-emissions development (LED) research outputs in Vietnam: Co-design of LED research priorities, outputs, and impact pathways for emissions reduction from the livestock sector

Key messages – Using a rational formulation tool (PC Dairy Software) with locally available feeds can increase productivity and income of dairy farmers and reduce methane emissions. This requires building the capacity of policymakers, extension officers, dairy farmers, and feed industries to facilitate the use of the livestock PC Dairy Software and the national deed database. – Co-designing low-emissions development (LED) research priorities, outputs, and impact pathways with user input ensures relevant research and generates impact. This helps develop and refine research outputs, communication with stakeholders, and integration into LED policies and strategies. – Promoting improved feed by using the national feed database and PC Dairy Software can contribute to achieving Vietnam’s greenhouse gas (GHG) reduction targets set in the nationally determined contribution (NDC) and green growth strategy (GGS)

Using fly ash treated by NaOH and H2SO4 solutions for Hg2+ and Cd2+ ion adsorption.

This paper presents the results of adsorption ability of heavy metal ions (Hg2+ and Cd2+) by fly ash (FA) before and after treatment using NaOH and H2SO4 solutions.  Original- and treated FA were characterized by Fourier Transform Infrared Spectroscopy (FTIR), X-ray Diffraction (XRD), and Scanning Electron Microscope (SEM). Specific surface area of FA before and after treatment was calculated by Brunauer – Emmett – Teller (BET) isotherm equation. The obtained results indicated that the morphology and specific surface area of FA changed clearly after treatment by acid or alkaline solutions. Adsorption capacity the Hg2+ and Cd2+ ion by FA was determined from data of UV-Vis spectra. After treatment, the adsorption capacity of ions by FA increased remarkably in comparison with non-treated FA. The FA treated by NaOH solution has the adsorption capacity higher than FA treated by H2SO4 solution. The maximum adsorption capacity of the FA treated by NaOH solution for Cd2+ and Hg2+ ions at room temperature is 28.97 and 14.60 mg/g, respectively. The equilibrium adsorption data were described by the Langmuir and Freundlich isotherm models. The results showed that equilibrium data were fitted well to the Langmuir isotherm. Keywords. Fly ash, treatment, adsorption capacity, heavy metal, Langmuir isotherm