The Journal of Industrial Technology

ปกวารสาร (cover) - JIT volume 22, issue 1, 2026

Editor — 2026-04-22

กองบรรณาธิการ (Editorial Board) / วัตถุประสงค์ (Objectives) / บทบรรณาธิการ (Editorial Note) / สารบัญ (Table of Contents)

Editor — 2026-04-22

The journal of Industrial Technology, 22(1), 2026

Editor — 2026-04-22

Effect of High Volume Ground Palm Oil Fuel Ash on Properties of Concrete Blocks

Napadon Sornpakdee — 2026-04-17

This research aims to study the effects of high-volume ground palm oil fuel ash (GPOFA) on the properties of concrete blocks, following the TISI 58-2560 standard for hollow non-load-bearing concrete masonry blocks. The binder-to-fine aggregate ratio (cement + GPOFA : stone dust) was set at 1 : 6 by weight, with four different mixtures containing 0, 50, 60, and 70 wt% of binder. Compressive strength tests were at curing ages of 7, 28, and 56 days, while water absorption and dry density were tests at 28 days. Additionally, the study analyzed production costs and the environmental assessment of the concrete blocks. The results indicated that replacing 70% of the cement with ground GPOFA wt% of binder, produced compressive strength up to 5.02 MPa or approximately 73% of the concrete blocks with cement as the binder material at 28 days, met the minimum specification of the standard for hollow non-load-bearing concrete masonry blocks (TISI 58-2560). However, concrete blocks with high volume of GPOFA decrease average density and an increase water absorption as the rate of cement replaced by GPOFA increased. Furthermore, using a high volume of GPOFA in concrete blocks reduced overall material costs by approximately 28 - 39% and decreased carbon dioxide emissions during production by up to 42 - 63% compared to concrete blocks made with cement as the binder.

A Data Management Framework and Mathematical Model for Worker Allocation Considering Skills and Upskilling in the Sewing Department of the Garment Industry

Nopruj Boonserm — 2026-04-17

The garment industry, particularly the sewing departments of made-to-order manufacturing factories, faces constant diversity and frequent changes in product designs. Many small-scale garment manufacturers in Thailand lack systematic tools or methods for task assignment; allocations are often made based on the personal experience of supervisors, resulting in subjective and inconsistent outcomes. In this industry, task allocation must not only ensure timely production but also promote task rotation to enhance the worker skills, improve work speed, and enable workforce flexibility through substitution. This study aims to develop a data management framework and mathematical model for skill-based worker assignment and skill enhancement in sewing departments of the garment industry. The data management framework provides a systematic approach for collecting and utilizing worker-related data, while the mathematical model is designed to be implemented with optimization tools for deriving optimal solutions. The proposed framework and model were tested using real-world data collected from a garment factory and supplemented with simulated data to assess the performance of the mathematical model. The experimental results demonstrate that the data framework effectively supports decision-making in worker assignment and rotation, and the mathematical model is capable of solving the optimal solutions within a real working timeframe.

Development of Workholding Fixture for Cycle Time Reduction in Flywheel Pulley Drilling on CNC Milling Machine

Nattapat Kanchanaruangrong — 2026-04-17

This research sought to develop and construct a suitable fixture for flywheel workpieces during the drilling process using a CNC milling machine, focusing on reducing cycle time and enhancing the manufacturing productivity of the case organization of the study. The research technique employed problem analysis with Why-Why Analysis and Left and Right Hand Charts to facilitate process enhancement grounded in the ECRS principle. The research found that the present problem resulted from the use of a three-jaw chuck, which could hold only a single workpiece every cycle. A new fixture was designed and manufactured to accommodate 9, 12, and 16 workpieces each cycle. Experimental findings from drilling 12 flywheel workpieces indicated that the hole position tolerance did not surpass 0.02 millimeters, the hole size tolerance is +0.020 millimeters, and the shaft tolerance is -0.004 millimeters, and no defective workpieces were detected. The average cycle time decreased from 43.55 seconds per piece to 42.53 seconds per piece, leading to an increase in the manufacturing productivity from 82.66 pieces per hour to 84.65 pieces per hour, representing an enhancement of 2.40%. The break-even analysis indicated that the minimum production volume required for the flywheel drilling process to be cost-effective is 257 sets per year.

Effect of Sea Water on Compressive Strength and Elastic Modulus of Concrete Portland Cement Type V Containing Ground Palm Oil Fuel Ash

Napadon Sornpakdee — 2026-04-20

This study investigates the effects of seawater exposure on the compressive strength and elastic modulus of concrete incorporating ground palm oil fuel ash (GPOFA) as a partial replacement for Type V Portland cement (SRC). GPOFA was used at 30%, 40%, and 50% by weight of binder. All specimens were cured in seawater 24 hours after demolding to simulate marine conditions. The binder content was fixed at 560 kg/m³ with a constant water-to-binder ratio of 0.28. Compressive strength was tested at 7, 28, and 60 days, and elastic modulus at 28 and 60 days. Results showed that 30% GPOFA replacement achieved 459.61 kg/cm² compressive strength at 60 days (approximately 88% of the control), with minimal impact on elastic modulus. Additionally, GPOFA use reduced CO₂ emissions by 24–40% compared to the control mix. GPOFA shows promise as a sustainable pozzolanic material for concrete in marine environments, with an optimal replacement level of 30–40% to balance performance and environmental benefits.

Enhancing Packaging Transport Efficiency Using Low-Cost Karakuri Kaizen Automation Mechanism

Siraprapha Deepradit — 2026-04-20

The objective of this research was to design and develop a low-cost automated packaging transport system based on Karakuri Kaizen principles (a Japanese lean manufacturing approach) to enhance production efficiency and to analyze the economic feasibility for Small and Medium-sized Enterprises (SMEs). The experimental design involved determining the optimal parameter by varying the inclination angles of the gravity conveyor at 9, 11, and 13 degrees. The results indicated that the 9-degree inclination yielded the highest operational performance. The implementation of the developed prototype significantly increased the production rate from 102.20 packs per hour to 275.00 packs per hour, representing a 1.69-fold increase in productivity. Furthermore, statistical analysis confirmed a significant difference in operational performance between the traditional and the developed systems (p < 0.05). Additionally, the economic feasibility analysis revealed a break-even point of 50 working days, demonstrating that the proposed system is a cost-effective investment for enhancing logistics efficiency in the manufacturing industry.

QFD-guided design of a Web-Based DSS Prototype for Sustainable Waste Management in Thailand

Prin Boonkanit — 2026-04-20

This study applied the Quality Function Deployment (QFD) method to translate stakeholder opinions and needs into technical features for developing a prototype web-based Decision Support System (DSS). In Thailand, municipal solid waste (MSW) and construction and demolition (C&D) waste are still difficult to manage, because the rapid growth of cities keeps increasing waste volume and straining local systems. The Decision Support System was created mainly to support local government organizations (LGOs) in making decisions that are more transparent and practical for real operation. Accessibility and usability were carefully checked under WCAG 2.1 standards by using the WAVE tool. The test results showed full compliance with accessibility criteria. A satisfaction survey among 25 experts reported an average score of 4.35 (SD = 0.56) and a satisfaction index of 87 % and 0 accessibility errors, showing strong acceptance. The results indicate that user involvement and simple design are important for future system adoption and for promoting Thailand’s Bio-Circular-Green (BCG) economy toward circular and sustainable waste management.

Investigation of Paddy Drying in a Curvilinear Impinging Stream Drying System Using Computational Fluid Dynamics

Patiwat Khomwachirakul — 2026-04-20

This research was to investigate the simulation of paddy drying in a curvilinear impinging stream drying system by computational fluid dynamics. In this study, a three-dimensional steady-state model was used to calculate the drying characteristics in a curvilinear impinging stream dryer. The gas and solid phase equations were solved using the Eulerian and Lagrangian methods, respectively. The model was used to simulate the effects of various parameters including inlet air velocity of 25 m/s, inlet drying air temperatures of 70, 90 and 110 ºC, paddy feed rate of 25, 35 and 56 kg/h on the paddy mean residence time, paddy mean moisture content and volumetric evaporation rate. Simulated results were compared with experimental data. The results showed that the model could predict the paddy mean residence time and paddy mean moisture content were close to the experimental results within ±6%. The simulated results revealed that the moisture reduction rate of the paddy depended both on the inlet drying air temperature and paddy feed rate. The maximum volumetric water evaporation rate was 62.72 kg_water/m³h when using inlet air velocity of 25 m/s, inlet drying air temperatures of 110 ºC and paddy feed rate of 56 kg/h. Based on the simulated results, the optimum paddy feed rate of this curvilinear impinging stream drying system was around 80 kg/h.

Development of a Microcontroller-Based Data Logger for Consolidation Testing

Aniroot Suksan — 2026-04-20

This study aims to develop a data logger for consolidation testing of clay soil in the laboratory. During the test, an industrial-grade displacement transducer was employed to measure the settlement of the soil sample. Analog signals from sensors were amplified and converted into digital signals using a low-cost conditioning module. Microcontroller-Based System programmed in C++ were developed to indicate and acquire the testing data. The sensor was calibrated with reference dial gauge before use. The one-dimensional consolidation testing by incremental loading was carried out on reconstituted clay using both dial gauge and the developed sensor. The settlement of clay measured during each test was compared. The unique consolidation properties of clay were used to validate the result. The results showed that the data logger developed in this study provides reliable and useful data for analyzing the consolidation characteristic of soil.

Predicting Micro-Crack Formation in XLPE Main Cables of Educational Building Power Systems Using Real-Time Three-Phase Current Data Analysis

Santi Karisan — 2026-04-21

This study presents a predictive approach for detecting micro-crack formation in XLPE main cables of an educational building power system using real-time three-phase current data collected over seven months (>60,000 samples) via an IoT monitoring system. After data cleaning and 5-minute resampling, statistical and temporal analyses revealed that Phase B consistently carried the highest load (7.41 ± 2.28 A in January 2025), while the Load Unbalance Index (LUI) rose from 8.45% to 13.05%, reflecting moderate imbalance. Cumulative thermal energy (I²) increased by 104%, with a strong correlation to LUI (r = 0.89). Logistic Regression and LSTM models estimated the probability of micro-crack occurrence , identifying a high-risk period in early January 2025 corresponding to a +9.7% current surge. The results confirm that real-time current analysis effectively indicates early XLPE insulation degradation and supports predictive maintenance for improved system reliability and energy management.

Feasibility Study on Technical, Economic, and Environmental Aspects of Synthetic Diesel Production from Natural Gas throughout Its Life Cycle

Pinnaree Kohsaman — 2026-04-21

This study evaluates the technical, economic, and environmental feasibility of producing 2,500 bbl/d of synthetic diesel from natural gas via autothermal reforming coupled with the Fischer–Tropsch process. Two energy management approaches were compared: (1) releasing excess energy and (2) recovering excess energy for reuse. Results show that the second strategy significantly reduces resource consumption, including cooling water (8,948,042 kg/d), heat (2,241 MMBtu/d), and electricity (784,662 kWh/d), compared with the first strategy, which relies heavily on external energy. Moreover, the recovery strategy delivers superior economic performance, with a ROI of 13.66%, IRR of 13.81% per year, NPV of USD 65 million, and a payback period of 6 years and 10 months. Efficient energy management also mitigates environmental impacts, particularly human toxicity, fossil resource scarcity, and global warming. The study highlights the potential of clean fuel production processes to support sustainable energy goals and reduce greenhouse gas emissions in Thailand.

Design and Experimental Study of a Prototype Device for Low-Temperature Hot Air Generation Using Atmospheric Plasma for Drying and Fungal Decontamination of Thai Herbs

Samit Preechayan — 2026-04-22

This study presents the design and experimental evaluation of a prototype system for generating low-temperature hot air integrated with atmospheric-pressure plasma for simultaneous herbal drying and fungal decontamination. The system combines a heat generation module with plasma-induced reactive species and a controlled hot-air circulation mechanism. Experimental results demonstrate that the prototype increased the internal air temperature from 24 °C to 34 °C using a single electrode, with an electrode surface temperature of approximately 53 °C. Drying experiments indicate that the system reduced the moisture content of sliced fingerroot by 16.6% within 40 minutes and sliced ginger by 10.53% within 60 minutes. In terms of antifungal performance, the total mold count on fingerroot surfaces was reduced to 0.8-7.5% of the initial contamination level. These results confirm the capability of the proposed system to simultaneously achieve moisture reduction and microbial decontamination within a single process. The developed prototype is particularly suitable for high-value herbs or seeds requiring low-temperature drying to preserve bioactive compounds while ensuring microbial safety, indicating strong potential for value-added processing in Thai herbal applications.

Natural Heat Convection Analysis on Boundary layer and Apply Utilization to Inclined Solar Collector

Sriwichai Susuk — 2026-04-22

Natural convection heat transfer driven by solar energy is a sustainable and environmentally friendly method for drying agricultural products, representing a critical mechanism in various solar dryer applications (free energy). This study experimentally investigates the laminar natural convection heat flow along an inclined solar collector under conditions approximating steady-state operation during peak sunlight hours. The research evaluates the velocity and temperature distributions on an inclined glass plate based on the development of thermal boundary layers. In addition to the limiting cases of flow adjacent to surfaces. Results indicate that the natural convection heat transfer coefficient ranges from 5.2 to 6.6 W/m²°C, while the collected heat energy ranges from 150 to 610 J/s, achieving a collector efficiency between 23.9% and 38.3%. The dry air flow rate was observed to be between 0.016 and 0.024 m³/s during daylight hours (local time). Under a fixed solar collector tilt angle of 25° and solar irradiation ranging from 217.8 W/m² to 552.7 W/m², the average Nusselt and Rayleigh numbers were determined to be 221.7 and 6.7x10⁹, respectively. Finally, load tests demonstrated a drying rate ranging from 0.07 to 1.45 kg/hr, which varied significantly based on local climatic conditions and the time of day.

The Design and Development of the Optimal Passive Micromixer to Accommodate a Wide Range of Flow Rates

Tuntita Arrayathiraputtitorn — 2026-04-22

This research focuses on the design and development of a passive micromixer to enhance fluid mixing efficiency at microliter and nanoliter scales. The study aims to optimize the microchannel structure to accommodate a wide range of flow rates without compromising mixing performance. A serpentine microchannel design with grooves was fabricated using experimental design methodologies to identify the optimal parameters for achieving high-resolution patterns on photoresist. Key factors affecting pattern clarity were investigated, including UV dose, stage Z height, and development time. Results revealed that stage Z height had the most significant impact, with data reliability reaching 99.82%. The performance of the developed micromixer was then evaluated through physical experiments and compared with conventional designs at flow rates up to 50 µL/min. Experimental results demonstrated that the new micromixer achieved Maximum mixing efficiency of 99.80% at the lowest flow rate (1 µL/min). Consistently high efficiency (>80%) across higher flow rates (10, 25 and 50 µL/min), though with a slight decline compared to lower flow rates. These findings confirm the device’s versatility across a broad flow rate range while maintaining robust mixing performance. The study highlights the potential for applications in chemical analysis and lab-on-a-chip systems requiring rapid and precise fluid mixing.