Journal of Science and Technology - IUH

DOMINANT ATTRIBUTIONS PHENOLIC COMPOUNDS IN LEPIDAGSTHIS THORELII EXTRACTS RESPONDING FOR ANTIOXIDANT AND ANTIMICROBIAL ACTIVITIES

Nguyễn Thị Ngần, Lê Văn Sơn, Phan Thị Hoàng Oanh, Trần Thị Huyền — Fri, 31 Oct 2025 00:00:00 +0000

Extracts from some species in the genus Lepidagathis have demonstrated biological activities such as antifungal, anti-inflammatory, antioxidant, and insecticidal propertie. Lepidagsthis thorelii is a species widely spreading from tropical to subtropical regions, however no research has been published on the antioxidant properties of this plant species until now. This study evaluated the TPC, phenolics, antioxidant, and antimicrobial activity of extracts from two L. thorelii parts by four extract solvents (methanol, ethanol, acetone, methylacetate). The methanol extracts obtained the highest TPC. Two methanol L. thorelii extracts and two acetone L. thorelii extracts with the relevant IC50 values (0.35, 0.39, 0.37, and 0.26 mg/mL) possessed remarkable properties of scavenging reactive oxygen species. The antioxidant capacities in three extracts indexed good correlations with their TPC values, except the L. thorelii flower. Methanol extracts revealed impacts to the growth of B. subtilis, and E. coli. The study confirmed extracts from L. thorelii provide potential phenolic compounds for antioxidant therapeutic applications or antimicrobial activity of L. thorelii extracts. This study first reported the presence of HBA and ferulic in L. thorelii as molecular indicators to understand the antioxidant potential of L. thorelii.

ARTIFICIAL INTELLIGENCE APPLICATION FOR ASSESSMENT OF SEASONAL RELATIONSHIP BETWEEN AIR HUMIDITY AND OTHER CLIMATE FACTORS IN NAMBO PLAIN

Dũng Trí Trần — Fri, 31 Oct 2025 00:00:00 +0000

This study evaluated the relationship between air humidity and other climatic factors at Nha Be, Can Tho and Rach Gia meteorological stations in Nam Bo plain during both dry - rainy seasons. The use of Artificial Neural Networks (ANN) to simulate air humidity for daily climate data in 2013 - 2020 period provided quite good results with 0.84 < R < 0.94 (or 0.71 < R² < 0.88). In particular, the analysis also showed that all obtained R_max series did not follow the normal distribution for 1000 simulations, although some series demonstrated a tendency to follow the Johnson Transformation distribution (most common), 3 - Parameter Weibull and Smallest Extreme Value. Elbow method of graphical evaluation has demonstrated the suitability of ANN structure with 1 hidden layer of 8 neurons using Tansig transfer function for simulating air humidity for all 3 stations. The calculation results proved that humidity value in dry season is most strongly related to daily evaporation, followed by the previous day's average humidity. However, for rainy season, the relationship strength in decreasing order is average temperature, followed by daily evaporation. Thus, daily evaporation is the most important factor with stable relationship to air humidity in survey area throughout the year.

SYNTHESIS OF PHOTOCATALYTIC MATERIALS OF TIO2 LOADED ON SA/PVP SUPPORT WITH RECOVERY ABILITY FOR APPLICATION OF ANTIBIOTICS TREATMENT FROM WATER UNDER UV AND SOLAR LIGHT IRRADIATION

Trung Quốc Lai, Thị Tường Vân Trần, Nguyen Chi Hieu — Fri, 31 Oct 2025 00:00:00 +0000

The trend of developing environmentally friendly materials that can be recovered and reused to completely eliminate waste is of interest and has potential for application. In this work, we synthesized photocatalytic materials using two methods: (1) mix sodium alginate with polyvinylpyrrolidone (SP), TiO₂-P25 powder mixed into SP and form hydrogel beads in CaCl₂solution (SP1-TiO₂) and (2) SP hydrogel beads soaked in suspension consisting of TiO₂-P25 and CaCl₂ (SP2-TiO₂). The experimental results demonstrated that SP1-TiO₂-0.4 material particles removed antibiotics oxytetracycline (OTC) and enrofloxacin (EFX) in aqueous solution under UV light and sunlight irradiation with the efficiency of 89.5% and 82.94% under UV light, and 83.89% and 79.46% under sunlight irradiation. The separation and recovery ability of this material from aqueous solution remained stable after 6 continuous decomposition cycles (only decreased by about 3-4%).

INACTIVATION OF GREEN TEA POLYPHENOL OXIDASE BY MICROWAVE

Fri, 31 Oct 2025 00:00:00 +0000

Polyphenol oxidases are a group of oxidative enzymes that catalyzes phenolic compounds. For high-quality green tea production, complete inactivation of these enzymes during the killing stage is essential. This research aims to improve the efficiency of polyphenol oxidase inactivation using microwave technology. The study evaluates the effectiveness of polyphenol oxidase inactivation using eight different techniques: blanching, steaming, pan-firing, microwaving, blanching with microwaving, steaming with microwaving, microwaving with steaming, and microwaving with blanching, applied to various components of raw materials, including buds, leaves, stems, and tea buds. The results showed that, for tea leaves, all enzyme inactivation methods have similar efficiency, with enzyme inactivation efficiency over 72.42%. For other components, such as buds, stems, and tea buds, the microwave-assisted methods provide better enzyme inactivation efficiency than traditional techniques like blanching, steaming, and pan-firing. Among these, the steaming combined with microwaving method was the most effective, reaching an inactivation efficiency of 70.7%. Additionally, when using microwave power at 600 W for 3 minutes, enzyme inactivation efficiency increases to 78.8%. This research outcome can be applied to real-world production, especially as industrial microwaves are now widely used

THE EFFECTS OF SEVERAL FACTORS ON STRUCTURAL CHARACTERISTICS OF FRIED RICE CRACKER

Trần Thị Mai Anh, Trương Hoàng Duy, Nguyễn Thị Mai Hương — Fri, 31 Oct 2025 00:00:00 +0000

Fried rice cakes, a popular snack across many Asian countries, are produced from glutinous or non-glutinous rice through steaming, drying, and frying processes. Typically, these products are manufactured on a small scale and require reheating by frying before consumption due to their tendency to lose crispiness during storage. This study aimed to develop an instant fried rice cake product using Vietnamese glutinous rice varieties. The research objective was to select suitable raw materials and processing parameters that ensure a crispy, porous structure during storage. Three varieties of glutinous rice, namely Golden flower glutinous rice, Northwest farm glutinous rice, Thai long-grain glutinous rice, were examined. Processing factors such as pre-steaming molding thickness (4 mm, 5 mm, 6 mm), drying temperature (50°C, 55°C, 60°C), residual moisture content (5%, 10%, 15%), frying temperature (190°C, 200°C, 210°C), and frying duration (20 s, 40 s, 60 s) were evaluated. Results indicated that samples made from Golden flower glutinous rice, molded at 5 mm thickness post-steaming, dried at 55°C to 10% moisture content, and fried at 200°C for 40 seconds exhibited structural characteristics comparable to Thai fried rice cracker brand Younger Farm- popular cracker in Vietnam market products. The study concluded that rice variety, molding thickness, drying temperature, moisture content, and frying parameters significantly influenced the structural and sensory quality of fried rice cake products.

FACTORS AFFECTING THE APPLICATION OF GREEN ACCOUNTING AT RUBBER ENTERPRISES IN THE SOUTHERN KEY ECONOMIC ZONE

Phạn Ngọc Hiền, Nguyễn Thị Mai Hương — Wed, 05 Nov 2025 00:00:00 +0000

This study was conducted in the period of 2024 - 2025, the main content focused on analyzing the influence of different determinants on the application of Green Accounting (GA) practices of 245 rubber enterprises in the Southern key Economic Zone. Using a mixed approach, the results of the analysis using a multivariate linear regression model with the support of SPSS software showed that factors such as managers' awareness, legal system, technological level, professional competence of accountants, pressure from stakeholders and business characteristics - all of which have a positive impact on the level of GA application in rubber enterprises. Among them, the factors identified as having the strongest impact are pressure from stakeholders and professional competence of accountants. This finding not only provides further empirical evidence on the role of internal and external factors in promoting GA, but also contributes to supplementing the theoretical basis for the application of GA in manufacturing enterprises to meet the sustainable development goals by 2030 in Vietnam.

CARBON ACCOUNTING: ITS ROLE IN CORPORATE SUSTAINABILITY

Nguyễn Ngọc Khánh Dung — Wed, 05 Nov 2025 00:00:00 +0000

In the context of climate change and increasing pressure to reduce greenhouse gas (GHG) emissions, carbon accounting has become a crucial management tool that enables businesses to meet environmental requirements and transition toward sustainable development. The purpose of this study is to clarify the role of carbon accounting in promoting corporate sustainability by closely integrating environmental, social, and governance (ESG) factors. The research employs a systematic literature review method based on scientific articles published in reputable journals. The research process includes the following steps: searching for relevant sources, screening materials, coding information, and content analysis according to five main themes: (i) environment, (ii) society, (iii) governance, (iv) competitive advantage, and (v) reputation. The results show that the governance factor accounts for the highest proportion (46.5%), followed by competitive advantage (23.7%) and corporate reputation (19.1%). Meanwhile, aspects related to the environment (7.3%) and society (3.3%) are addressed to a lesser extent. These findings suggest that, beyond its original role of measuring and monitoring environmental impacts, carbon accounting is being increasingly utilized as a strategic decision-support tool, particularly in enhancing corporate governance efficiency and competitive capacity. The adoption of transparent and accurate carbon reporting systems not only helps businesses minimize legal and operational risks and optimize production costs but also contributes to increasing market value and strengthening stakeholder confidence. Therefore, the study emphasizes the importance of establishing a coherent legal framework and robust internal policies to effectively implement carbon accounting systems, thereby promoting business performance and enhancing the company’s competitive position in the global market.

THE IMPACT OF GREEN LOGISTICS MANAGEMENT AND INDUSTRY 4.0 ON SUSTAINABLE PERFORMANCE

Wed, 05 Nov 2025 00:00:00 +0000

In today's digitalization context, especially after the Covid-19 pandemic, environmental factors are increasingly prioritized by businesses. The government is also promoting digital transformation and encouraging the adoption of green logistics in supply chains. However, research on this topic in Vietnam remains limited, mainly focusing on green supply chain management practices and sustainable performance, with few studies targeting specific entities such as technological sources and green logistics privilegde. This study aims to identify and measure the impact of green logistics management and Industry 4.0 technology on the sustainable performance of logistics enterprises in Ho Chi Minh City, while also evaluating the influence of each factor. The study is based on data from over 170 official responses and analyzed using SmartPLS. The results show that green logistics management and industry 4.0 technology have a positive impact on sustainable performance, with the circular economy and green supply chain management also acting as an intermediary. The authors suggest that small and medium-sized enterprises should invest in green logistics management and circular economy practices to improve their sustainable performance. Integrating digital technologies can also support green supply chain management and enhance businesses' environmental, social, and economic efficiency, support green supply chain management and enhance the environmental, social, and economic efficiency of businesses

CULTURAL DIPLOMACY BETWEEN VIETNAM AND SOUTH KOREA (1992-2024)

Đặng Thị Minh Phượng — Fri, 31 Oct 2025 00:00:00 +0000

In 1992, Vietnam and Korea established diplomatic relations. By 2022, Korea will be the fourth country (after China, the Russian Federation and India) to upgrade to a “Comprehensive Strategic Partnership” with Vietnam. During the 32 years (1992-2024), the diplomatic relationship between the two states of Vietnam and Korea has always been consolidated, fostered, and effective in all aspects from politics, defense – security, economics, science, education, tourism... In the fields of Vietnam-South Korea cooperation, cultural diplomacy in various diverse forms has made important contributions to strengthening the solidarity, friendship, and bilateral cooperation between the two nations. This study focuses on clarifying certain factors and outcomes, while proposing several solutions to further maintain and elevate the “comprehensive strategic partnership” between the two countries in cultural diplomacy, both in the present and the future.

APPLICATION OF REGRESSION ANALYSIS TO MODEL THE CORRELATIVE RELATIONSHIP OF THREAD TENSION AND FABRIC THICKNESS ON SEAM PUCKERING

Phan Hà Như Ngọc — Wed, 05 Nov 2025 00:00:00 +0000

This study focuses on elucidating the correlative relationship between bobbin thread tension and fabric thickness on the degree of seam puckering in the garment industry. By applying a second-order factorial experimental design methodology combined with multivariate regression model analysis, the study identified the influencing factors and determined the magnitude of their effects on seam length variation. The analysis results indicate that fabric thickness is the predominant factor affecting puckering, having a significantly larger impact compared to bobbin thread tension. Based on the developed regression equation, optimal bobbin thread tension values corresponding to each level of fabric thickness have been determined to minimize seam puckering.

THE ROLE OF SCHOOL CULTURE IN DEVELOPING DIGITAL CULTURE IN CONTEMPORARY VIETNAM

Nguyễn Thị Thúy Cường — Wed, 05 Nov 2025 00:00:00 +0000

This article examines the role of school culture in the process of building a digital culture in contemporary Vietnam. Based on a theoretical analysis of both school culture and digital culture, the article argues that school culture is not only an environment for education and character formation but also a foundational platform for fostering digital thinking, critical thinking, and digital ethics among younger generations. The paper evaluates the current state of technology integration, the development of digital thinking and ethics, and behavioral patterns within school environments. It also highlights both the achievements and existing limitations, such as the digital divide between regions, the lack of digital culture content in curricula, and the insufficient technological competencies among educators. Furthermore, the article identifies the underlying causes of these achievements and challenges. Based on these findings, it proposes several key solutions to advance school culture in alignment with the development of digital culture in Vietnam today.

SILVER NANOWIRE (AGNW) ELECTRODES ON PET SUBSTRATES FOR APPLICATION IN FLEXIBLE ELECTRONIC DEVICES

Hoàng Thị Thu — Wed, 05 Nov 2025 00:00:00 +0000

Currently, the demand for flexible electronic devices – capable of bending, such as TVs, smartphones, laptops, tablets, and solar cells – is rapidly increasing and has become an inevitable development trend, ushering in a new era in smart materials and device technology. One of the key factors determining the success of flexible optoelectronic devices is the fabrication of transparent conductive electrodes on flexible substrates. In this study, we successfully fabricated flexible, transparent, and conductive electrodes based on silver nanowires (AgNWs). This material shows great promise as a cost-effective and high-performance alternative to conventional ITO electrodes, offering excellent flexibility. The silver nanowires were synthesized using the polyol method, with an average diameter of approximately 50 nm and a length up to 50 µm, achieving an aspect ratio (length/diameter) of up to 1000 – highly favorable for flexible electronics applications. The resulting AgNW-based electrode film exhibited high optical transmittance (>80%) and a good figure of merit (104), comparable to traditional ITO electrodes on rigid substrates. Moreover, the electrode maintained stable optoelectronic performance after more than 800 bending cycles, clearly demonstrating its potential for next-generation flexible electronic devices.

FORECASTING NEW ZEALAND HOUSING DEMAND: COMPARING ELASTIC NET, XGBOOST AND RNN MODELS

Binh Thanh Dang, Chuong Bui Viet — Wed, 05 Nov 2025 00:00:00 +0000

Forecasting housing demand has been a prevalent research focus globally, primarily employing traditional econometric methods. However, the application of machine learning in this domain remains limited, particularly in the New Zealand context. This study addresses this gap by implementing Elastic Net, XGBoost, and Recurrent Neural Network models to predict residential housing demand in New Zealand using historical economic and demographic data from 1995. The models were evaluated using a comprehensive framework of six complementary metrics (R², SMAPE, MAE, RMSE, MBE, and MASE), with the RNN model achieving the highest accuracy. Results demonstrate that machine learning algorithms significantly enhance housing demand forecasting, with temporal models outperforming traditional approaches. The analysis of feature importance identified CPI, construction investment, import values, and unemployment as key drivers, while demographic factors showed limited impact on housing demand. These findings provide valuable insights for policymakers and construction firms addressing New Zealand's housing challenges. Future research should expand dataset dimensions and improve model interpretability

ROBUST ADAPTIVE NEURAL TRACKING CONTROL FOR UNDERACTUATED NONLINEAR SYSTEMS: A ROTARY INVERTED PENDULUM CASE STUDY

Nguyễn Hoàng Hiếu, Mai Thăng Long, Nguyễn Ngọc Sơn — Fri, 31 Oct 2025 00:00:00 +0000

The underactuated system demonstrates significant coupling and highly nonlinear dynamics, posing challenges for precise control. This paper introduces an adaptive control approach for the underactuated rotary inverted pendulum (RIP) system. The objective is to enable the manipulator arm to track a desired trajectory and to maintain the pendulum in an upright position concurrently. The proposed method employs two neural networks: the first focuses on tracking the desired trajectory of the manipulator arm, while the second stabilizes the pendulum in its upright position. Stabilize the system using Lyapunov theory. To validate the effectiveness of the proposed control strategy, experiments are conducted using the NI-PCI 6221 data acquisition card with the RIP system. Both simulation and experimental results underscore the robustness of the proposed control method against system uncertainties and external disturbances, achieving stable operational performance.

DESIGN AND DEVELOPMENT OF LOW - SPEED WIND TUNNEL

Đặng Tiến Phúc, Bùi Chí Thành, Phạm Việt Phương — Wed, 05 Nov 2025 00:00:00 +0000

The wind tunnel is an important system for testing in the research and development of aeronautical, automotive, and industrial designs that focus on the aerodynamic characteristics of moving objects. This paper presents the design and fabrication of an open-circuit wind tunnel with a test section measuring 500 × 500 mm. Within this section, wind speeds can reach a maximum of 15 m/s, as measured by the Extech SDL350 anemometer. The aerodynamic forces are recorded using the GPB160-1 load cell system. Experiments were conducted on three models: cubes, spheres, and cylinders, at velocities of 10 m/s and 15 m/s. Compared to the reference values, the errors for the cubic model were 4.57% at 10 m/s and 4.95% at 15 m/s. Similarly, the errors for the spherical model were 3.61% at 10 m/s and 4.61% at 15 m/s, while those for the cylindrical model were 3.6% at 10 m/s and 4.6% at 15 m/s. The test results demonstrated that the wind tunnel exhibits high reliability and stability. This system contributes to developing of shape-optimized designs, enhancing aerodynamic performance and vehicle safety.

A QUASI-2D MODEL FOR PREDICTING ENTRAINMENT CHARACTERISTICS OF EJECTORS UNDER VARIOUS OPERATING CONDITIONS

Nguyễn Trung Kiên, Cao Trung Hậu, Nguyễn Hiếu Nghĩa, Kiên Nguyễn — Wed, 05 Nov 2025 00:00:00 +0000

The ejector is a key component in low-grade thermal refrigeration systems thanks to its simple construction and its potential to boost cycle efficiency. This paper presents a quasi-2D mathematical model that accurately predicts entrainment ratio of ejector in both critical and sub-critical regimes. Unlike conventional one-dimensional methods, the quasi-2D approach captures the radial velocity distribution, boundary-layer effects, and shock-wave region. The model is validated against a wide experimental database covering several refrigerants and operating conditions; the maximum deviation is below 7%, while pressure trends and entrainment ratios—especially in the sub-critical zone—are reproduced faithfully. These results highlight the necessity of simultaneously accounting for axial and radial flow directions and provide a reliable basis for ejector geometry optimisation, ultimately improving the COP of ejector-based refrigeration systems.