Journal of Science and Technology - IUH

DETERMINATION OF THE OPTIMAL HARVEST TIME OF THE CULTURE MEDIUM OF VIETNAMESE-ISOLATED Cordyceps militaris WITH THE HIGHEST ANTIOXIDANT ACTIVITY

Wed, 25 Mar 2026 00:00:00 +0000

Cordyceps militaris, commonly known as a medicinal mushroom, is a valuable fungus renowned for its high content of antioxidant compounds such as flavonoids, polyphenols, and cordycepin. Harvest timing plays a crucial role in optimizing the concentration of these bioactive compounds, thereby enhancing the medicinal value of the fungus. However, the fruiting bodies are typically expensive.This study was conducted to determine the optimal harvest time for C. militaris CULTURE MEDIUM that yield the highest antioxidant activity. The experiment involved harvesting the CULTURE MEDIUM at various growth stages—days 0, 10, 20, 30, 40, 50, and 60—corresponding to developmental phases from mycelial growth to mature fruiting bodies.The chemical composition of the substrates was analyzed using Gas Chromatography-Mass Spectrometry (GC-MS), and antioxidant activity was evaluated by determining total polyphenol content, reducing power, and DPPH (2,2-diphenyl-1-picrylhydrazyl) free radical scavenging capacity.The results indicated that antioxidant activity increased progressively with growth duration, peaking at the mature fruiting body stage on day 50. These findings provide essential scientific evidence for optimizing the harvest process of Cordyceps militaris cultivation in Vietnam, contributing to the improvement of raw material quality for the domestic pharmaceutical and nutraceutical industries, while supporting the development of a circular bioeconomy.

RESEARCH ON SOIL QUALITY FOR ACACIA PLANTING IN MOUNTAINOUS AREAS IN TAY SON DISTRICT, BINH DINH PROVINCE

Nguyễn Văn Phương — Wed, 25 Mar 2026 00:00:00 +0000

Integrating soil quality control into acacia cultivation in mountainous regions represents a critical strategy for sustainable agriculture. This study employed Principal Component Analysis (PCA) to evaluate soil quality in the acacia-planted hilly region of Tay Son district, Binh Dinh province, based on 12 composite soil samples and 7 selected indicators (bulk density, particle density, sand content, silt content, pH, EC, and TOC). PCA aided in reducing data redundancy and determining relative weights (Wi) along with soil indices (Si) to calculate the Soil Quality Index (SQI). The results indicated that 2 principal components explained 68.7% of the data variability, and identified 2 representative indicators: % sand and NH₄⁺. The majority of the study area exhibited medium soil quality (83%). The Soil Quality Index (SQI) has been identified as a powerful tool to help manage agriculture effectively and sustainably, contributing to improving the lives of local farmers.

DESIGN, SCREENING AND EXPLORING NOVEL METAL-THIOSEMICARBAZONE COMPLEXES TARGETING HT-29 CELL LINE USING QSPR-BASED IN SILICO MODELING

Minh Quang Nguyen, Pham Van Tat — Wed, 25 Mar 2026 00:00:00 +0000

In silico models were used to calculate the stability constants (logb₁₁) of metal ions and thiosemicarbazone in complex solutions. The 0-3D molecular descriptors, physicochemical, and quantum parameters were produced using the semi-empirical quantum computation PM7 and PM7/sparkle as well as the molecular geometric structure. Multivariate linear regression (MLR) and artificial neural networks (ANN) were used to build the quantitative structure and property relationship (QSPR). The constructed QSPR_MLR model involves descriptors such as: k0, core-core repulsion, xvp10, ⁵C, and xch5. The statistical values of the model were pointed out: R²_train = 0.847, R²_adj= 0.834, Q²_LOO = 0.764, SE = 1.371, and F-stat = 66.20. The neural network QSPR_ANN I(5)-HL(8)-O(1) model was also developed with the statistical values: R²_train = 0.976, Q²_test = 0.956, and Q²_validation = 0.926. A series of new thiosemicarbazone derivatives and complexes of this ligand and metal ions were designed using these models. These complexes were screened using the Applicability Domains (AD) and Outliers technique. The ability prediction of models applied complexes on the test data set agrees with those from the experimental literature. Besides, the results of fifteen new complexes were selected because they were within the predictive application domain. Next, nine of fifteen new complexes overcame drug-likeness analysis of Lipinski and Veber rules. Finally, nine typical complexes simulated the docking on protein for anti-colorectal cancer (code: 6GUE-PDB). The results screened out six novel complexes considered potential inhibitors to the HT-29 cell line in supporting colorectal cancer treatment.

ANALYZING URBAN GREEN SPACE IN SOUTHERN CITIES OF BINH DUONG PROVINCE, VIETNAM USING REMOTE SENSING AND GIS TECHNIQUES

Bui Dang Hung — Wed, 25 Mar 2026 00:00:00 +0000

This study evaluated the spatial and temporal change in urban green space (UGS) in the southern cities of Binh Duong province. Landsat multi-temporal images from 2001 to 2020 were analyzed. The random forest algorithm was used to generate land cover maps, which were then reclassified to UGS maps. The results showed that UGS continuously decreased in the period 2001 – 2020 in the study area. About 67.3% of UGS in the entire study area have been lost during this time. As of 2020, the remaining UGS of the study area was 6,707 hectares, corresponding to an average coverage rate of 25.6% and a ratio of 46.1 m² UGS per capita. Although the overall UGS was still guaranteed to be above the minimum of 9 m² per capita, only 79.2% of the urban area was within a distance of 300 m from UGS of at least 0.5 ha. This can reduce the ability of urban residents in this area to benefit from green spaces.

FACTORS INFLUENCING MOBILE BANKING ADOPTION AMONG GENERATION X: APPLYING UNIFIED THEORY OF ACCEPTANCE AND USE OF TECHNOLOGY AS WELL AS DIFFUSION OF INNOVATION THEORY

Phan Hồng Hải — Sat, 28 Feb 2026 00:00:00 +0000

This study aimed to explore the factors influencing the adoption intention of mobile banking among Generation X customers in Vietnam, a demographic often more cautious in accepting new technologies. Based on the integration of the Unified Theory of Acceptance and Use of Technology (UTAUT) and Diffusion of Innovation (DOI) theory, the study examined the roles of performance expectancy, effort expectancy, attitudes toward mobile banking, and digital transformation capability. Using a quantitative survey method, data were collected from 152 Generation X customers and analyzed through the PLS-SEM model. The results indicated that attitudes played a critical mediating role, positively influenced by performance expectancy, and effort expectancy. Digital transformation capability also had a significant impact on mobile banking adoption intention. In conclusion, the study highlighted the importance of focusing on user experience, providing digital skills training, and designing simple interfaces to promote mobile banking adoption within this customer group

BIBLIOMETRIC ANALYSIS IN BUSINESS MANAGEMENT: PROCESSES, TOOLS, AND PRACTICAL APPLICATIONS

Nguyễn Ngọc Long — Wed, 25 Mar 2026 00:00:00 +0000

Bibliometric analysis in Business Administration is an essential research method for evaluating and synthesizing scientific literature. This paper comprehensively presents the process of conducting bibliometric analysis. The steps include identifying the research problem, selecting appropriate databases, collecting relevant documents, analyzing, and synthesizing data. Each step is detailed with the necessary techniques and supporting tools. By applying bibliometric analysis, the paper demonstrates that this method not only helps identify research trends but also uncovers gaps in existing literature. This facilitates the development of new research and improves the quality of scientific works. The paper emphasizes that bibliometric analysis is a powerful tool for researchers and scholars in evaluating and advancing scientific knowledge. Proper implementation of the analysis process will enhance the accuracy and reliability of research outcomes

AUDIT JUDGMENT: AN EMPIRICAL STUDY IN HO CHI MINH CITY

Lê Thủy Ngọc Sang, Bùi Thị Tú Uyên — Wed, 25 Mar 2026 00:00:00 +0000

This study investigates the influence of four key factors - professional competence, audit fees, auditor independence, and external motivation - on the professional judgment of independent auditors in the context of financial statement audits in Ho Chi Minh City, Vietnam. Using survey data from 299 auditors, the study applies Partial Least Squares Structural Equation Modeling (PLS-SEM) via SmartPLS 4.0 to analyze the relationships among variables. The findings reveal that both professional competence, auditor independence and external motivation significantly and positively influence the quality of professional judgment. Professional competence, encompassing technical knowledge, practical skills, and professional skepticism, enhances auditors’ ability to interpret evidence and make sound decisions. External motivation, such as reward systems and societal contributions, also exerts a positive impact, though it must be carefully managed to preserve auditor objectivity. The study recommends that auditing firms prioritize strengthening auditor independence, invest in continuous professional development, and implement well-balanced motivational frameworks to enhance audit quality. These insights contribute to both the academic understanding and practical improvement of professional judgment in financial auditing.

FACTORS INFLUENCING THE INTENTION AND BEHAVIOR OF USING MOBILE COMMERCE SERVICES: THE CASE OF VENDORS IN THE INFORMAL SECTOR IN HO CHI MINH CITY

Phan Tuấn An, Nguyễn Thị Túc — Wed, 25 Mar 2026 00:00:00 +0000

In the process of digitalizing the economy, access to technology is no longer an exclusive privilege of formal enterprises but is gradually permeating informal economic activities. Currently, many business establishments are beginning to adopt mobile commerce (m-commerce) services to enhance operational efficiency. However, vendors operating within the informal economy remain hesitant to embrace such technologies. Therefore, this study aims to explore the determinants that drive their intention to use m-commerce services, thereby promoting actual usage behavior. Data were collected from 252 informal vendors using quota sampling and analyzed with SPSS and SmartPLS. The findings indicate that usage intention plays a crucial mediating role, linking six positively influential factors to actual usage behavior: perceived trust, social influence, perceived ease of use, perceived usefulness, facilitating conditions, and hedonic motivation. Based on these insights, the study also offers managerial implications to encourage vendors in the informal sector to adopt mobile commerce in their business operations.

FACTORS AFFECTING LOCAL ENGAGEMENT IN HOMESTAYS IN THE EASTERN MEKONG DELTA REGION

Hien Hoa Do, Xuan Vinh Ma, Thuong Le — Wed, 25 Mar 2026 00:00:00 +0000

This study examines the factors influencing local community engagement in homestay tourism within the Eastern Mekong Delta region, comprising Tien Giang, Vinh Long, and Ben Tre provinces. Drawing on Community Participation Theory, Trust Theory, and Expectancy Theory, the research identifies four key factors: local government support, economic benefits, trust, and individual perception. Employing a mixed-methods approach, the study collected and analyzed 315 valid responses from residents and homestay workers using SmartPLS 4.1.0.0. The measurement model demonstrates strong reliability, convergent validity, and discriminant validity. Structural equation modeling results reveal that all four factors exert statistically significant and positive influences on community participation in homestay tourism, with economic benefits being the most influential driver. The findings provide empirical insights into community motivations and offer practical managerial implications, including enhancing income-generating opportunities, fostering trust, raising awareness, and improving governance frameworks. These strategies are crucial for promoting sustainable homestay development and improving local livelihoods in the Eastern Mekong Delta

GLOBAL CITIZENSHIP EDUCATION FOR UNIVERSITY STUDENTS: A CASE STUDY AT INDUSTRIAL UNIVERSITY OF HO CHI MINH CITY

Lê Thanh Hòa — Wed, 25 Mar 2026 00:00:00 +0000

In the context of globalization and international integration, global citizenship education has become a strategic priority in higher education development. This paper analyzes how students are educated to become global citizens at the Industrial University of Ho Chi Minh City (IUH). Drawing on theoretical frameworks on global citizenship proposed by UNESCO, OECD, and Oxfam, the study surveyed 400 students to assess their levels of awareness, skills, and attitudes toward global citizenship. The findings reveal that most students demonstrate positive perceptions of global citizenship; however, their foreign language proficiency, intercultural competencies, and ability to participate in global activities remain limited. The study also highlights IUH’s efforts to integrate global citizenship education into academic programs and extracurricular activities, while identifying challenges such as limited resources and uneven access to international opportunities. Based on these findings, the paper proposes several solutions to enhance the effectiveness of global citizenship education for students in the context of global integration.

DETERMINING KEY PRODUCT ATTRIBUTES OF WOMEN’S BRAS AFFECTING USAGE DECISIONS - A QUALITATIVE DATA ANALYSIS APPROACH

Đào Lý Minh Thư, Nguyễn Thị Mộng Hiền — Wed, 25 Mar 2026 00:00:00 +0000

This study explores the key product attributes influencing young women’s decisions to select and use brassieres, employing a qualitative approach that combines in-depth interviews and open-ended questionnaires. The target group comprised women aged 18–25, a consumer segment particularly sensitive to variations in material, fit, structure, and fashion trends. Data collected from 10-15 in-depth interviews and 50 open-ended surveys were processed through content analysis and thematic analysis, allowing for systematic coding, categorization, and theme extraction. Findings highlight six core factors shaping consumer choices: structure and components, comfort, functionality, material, form/fit/aesthetics, and other contextual aspects. Notably, two emerging concerns were revealed: the importance of invisibility (non-marking, seamless appearance under clothing) and the preference for eco-friendly materials such as organic cotton or recycled fabrics. These insights extend functional of intimate apparel. The study demonstrates the value of qualitative inquiry as a foundation for building quantitative measurement scales in subsequent research. Limitations include the relatively small sample size and restricted geographic scope, suggesting that future studies should expand participant diversity and apply quantitative validation to strengthen generalizability.

ENHANCING KNIT JACKET SEWING QUALITY THROUGH PARETO AND FISHBONE DIAGRAM ANALYSIS

Phan Hà Như Ngọc, Trần Thảo Ngà, Phạm Thị Linh — Wed, 25 Mar 2026 00:00:00 +0000

In the highly competitive landscape of the Vietnamese textile industry, the quality of knitwear products is paramount, yet production errors frequently lead to waste and diminish competitiveness. This study presents the application of basic quality control tools – the Pareto chart and the fishbone (Ishikawa) diagram – to analyze and propose solutions for quality improvement within a major textile enterprise, utilizing a case study approach on a specific knit jacket order (code 0513). Pareto analysis identified three primary defects accounting for 80.1% of total failures: broken stitches on the placket edge (30.1%), skipped stitches on the hem (26.5%), and puckered zipper seams (23.5%). Subsequent root cause analysis using fishbone diagrams revealed core factors related to equipment (suboptimal settings for parameters like thread tension, presser foot pressure, needle-hook distance), personnel (inadequate operational skills in handling fabric elasticity, material feeding speed), and materials (incompatibility in shrinkage between fabric and zipper, fabric thickness). Based on these findings, proposed solutions include optimizing machine settings, standardizing processes and operations via visual guides and fabric handling techniques, enhancing worker training, and thoroughly checking material compatibility. The research confirms that the systematic application of quality control tools effectively identifies critical issues and root causes, providing a solid foundation for effective and sustainable quality improvement actions in knitwear production.

RESEARCH ON THE DESIGN OF ABDOMINAL SHAPING UNDERWEAR FOR WOMEN AND EVALUATION OF THEIR SHAPING ABILITY OVER TIME OF USE

Wed, 25 Mar 2026 00:00:00 +0000

Women's abdominal shaping underwear ĐT is made of double loop single jersey knit fabric from 2 types of yarns, the first yarn is a DTY (draw textured yarn) polyamide and DTY polyamide with spandex core, the second yarn is 100% spandex single yarn. The products were designed to be smaller than the model's body size, so that when all four models wore them, the DT fabric stretched horizontally by 34%, corresponding to a tensile force of 0.446 Kgf. This elongation is within the 100% elastic range. Thanks to this, they have the ability to shape the abdominal area. The shaping ability of the product is evaluated by the reduction in the user's abdominal measurement as a % of the abdominal measurement when not using the product. Abdominal circumference was measured manually directly by the user. The model's abdomen was measured 3 times during 1 usage cycle (15 minutes after starting to wear, after 4-6 hours and after 18-12 hours). The product's shaping ability was observed over 20 use cycles (wearing for 12 hours – washing – drying). Initial research results showed that the abdominal circumference of 4 models decreased by 5,2-0,6% when wearing shaping underwear. The results show that the shaping ability is quite stable during a usage cycle. They are quite stable for the first 5-8 cycles of use, and start to decrease slightly from the 6th cycle. Compared with a similar product currently circulating on the market, DX underwear, their shaping ability only reaches 0-2,1% even though both are used under the same tensile force. During a cycle of use, DX products lose their shaping ability from the fourth hour of use. Observation of 20 use cycles showed that the formability of DX products started to decrease from the fourth use cycle.

NUMERICAL STUDY ON THE CO-INJECTION CHARACTERISTICS OF COAL AND AMMONIA IN A SWIRL BURNER

Wed, 25 Mar 2026 00:00:00 +0000

Co-firing NH₃ with coal is a promising solution for reducing CO₂ emissions, although it remains relatively new technology in Vietnam. This study employs CFD simulation using STAR-CCM+ software to perform the spray characteristics and NH₃ concentration distribution in a swirl burner, with a co-firing ratio of 10% NH₃, based on thermal input. The ammonia injection tube length was adjusted at five positions of 0 m, 0.4 m, 0.8 m, 1.0 m, and 1.2 m. Results show that the injector position significantly affects flow behaviors and NH₃ concentration. At 0.8 m, a central recirculation zone (CRZ) begins to form with a swirl number of 0.277. At 1.0 m, the CRZ becomes stable, and the lowest NH₃ concentration (0.3165 m³) is observed, indicating favorable conditions for stable combustion. Increasing the injector length reduces the volume of high NH₃ concentration regions, thereby improving combustion efficiency and limiting NH₃ presence in high-oxygen zones. These findings provide valuable technical insights for the design and operation of burners in coal–ammonia co-firing systems.

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, 25 Mar 2026 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.

DETERMINATION OF YOUNG’S MODULUS AND COEFFICIENTS OF THERMAL EXPANSION FOR A CMOS-MEMS PROCESS USING OUT-OF-PLANE ELECTROTHERMAL CANTILEVERS

Ngô Tiến Hoàng — Wed, 25 Mar 2026 00:00:00 +0000

Many foundries now have a variety of standard CMOS processes available. In microelectromechanical systems (MEMS) as well as in integrated circuits, metallic layers are arranged alternately with dielectric layers in some processes that represent technological advances. The material properties of the metal and dielectric films need to be considered to calculate the performance and suitability of micro devices. This study applies an existing approach to encompass the coefficients of thermal expansion (CTEs) of metal and dielectric films for standard CMOS processes. The cantilevers have been designed and implemented with different stacking of metal and dielectric layers for standard CMOS processes. The out-of-plane thermal displacement of the test cantilevers can be measured to evaluate the CTEs of standard CMOS films.

BUILDING SLIDING MODE CONTROLLER FOR BALANCING NONLINEAR BALL AND BEAM SYSTEM

Bốc Minh Hùng — Wed, 25 Mar 2026 00:00:00 +0000

In recent years, many subjects have been interested in designing controllers for nonlinear model systems for testing various control algorithms. Many education nonlinear system models are unstable. The complete system in this paper includes a ball, a beam, a motor, and several sensors. The torque is generated by the motor to control the position of the ball and beam system, where the ball rolls freely on the beam. A control law is developed, and asymptotic stability based on sliding surface. The purpose is to design a controller for the ball position with the optimal energy and minimum overshoot. To illustrate the efficiency of the proposed controller, the simulation results at different working points are demonstrated and compared with other controllers. Finally, the control algorithms are compared together to recognize the best solution

A SURVEY ON PROTOCOL STACK FOR WIRELESS BODY AREA NETWORK

Ong Mau Dung — Wed, 25 Mar 2026 00:00:00 +0000

Wireless Body Area Network (WBAN) is a radio-frequency wireless network, with comparatively short coverage range. It consists of a potentially large number of low-power consumption devices with sensor or actuator functionality. Considering the capability of innumerous kinds of sensors, WBAN does have a lot of application scenarios around human body area, among which there is personal healthcare. When applied to scenarios like healthcare, WBAN may then interact with other networks in close proximity to largely extend its communications area. This paper presents a survey on ultra-low-power and low-rate version of WBAN by comparing two non-proprietary protocol stacks, namely ZigBee/IEEE 802.15.4 and Wibree. IEEE 802.15.6 and UWB are two others wireless technologies that can be applied in WBANs, yet each is oriented toward different application requirements. In scenarios where latency is a critical factor - such as arrhythmia detection, emergency alerts, or intraoperative monitoring - ultra-low latency must be prioritized, making IEEE 802.15.6 and UWB more suitable. Conversely, for less time-sensitive applications, including fitness tracking or periodic data collection, BLE and ZigBee provide more energy-efficient solutions. Wibree was initially referred to as Bluetooth Low-End Extension (LEE) and subsequently as Ultra-Low-Power (ULP) Bluetooth. To better illustrate Wibree, Bluetooth’s specifications is included into comparison whenever necessary. Moving from physical layer to application layer, we have compared different schemes employed by each protocol stack. After that, we investigated into the application of sensors, with the aim of interconnecting arrays of biomedical sensors.